184637033 GBA Flare Systems

GBA Ltd Burnham House 93 High Street Burham SL1 7JZ England

GBA Srl Via Ramazzotti, 24 20052 MONZA Milan Italy

GBA-Corona Inc. 10333 Harwin Suite 110, Houston Texas 77036 USA

Tel.: +44-(0)1628-610100 Fax.: +44-(0)1628-610170 E-Mail: [email protected]

Tel.: +39-039-492718 Fax.: +39-039-2494257 E-Mail: [email protected]

Tel.: +1-713-773-9933 Fax.: +1-713-773-9940 E-Mail: [email protected]

COMPANY PRODUCT MANUAL Page 1

1. ONSHORE FLARE SYSTEMS. ................................................................. 4 1.1. 1.2. 1.3. 1.4.

INTRODUCTION....................................................................................................................................................4 FLARE TYPES AND APPLICATION....................................................................................................................4 FLARE SYSTEM DESIGN. ....................................................................................................................................6 KEY COMPONENTS..............................................................................................................................................6

2. PRODUCT LISTING AND ENGINEERING CAPABILITIES. .......... 13 2.1. 2.2. 2.3. 2.4. 2.5. 2.6. 2.7. 2.8. 2.9. 2.10. 2.11. 2.12.

GENERAL. ............................................................................................................................................................13 DESIGN CAPABILITIES......................................................................................................................................13 DESIGN AND SUPPLY OF INTEGRATED FLARE SYSTEMS........................................................................13 DESIGN AND SUPPLY OF FLARE TIPS AND BURNERS...............................................................................14 FLARE CONTROL AND SAFETY SYSTEMS. ..................................................................................................14 TECHNICAL DESIGN CONSULTANCY SERVICES........................................................................................14 INSTALLATION/ERECTION. .............................................................................................................................14 COMMISSIONING. ..............................................................................................................................................14 MAINTENANCE...................................................................................................................................................14 DESIGN AND SUPPLY OF STEEL STRUCTURES...........................................................................................15 DESIGN AND SUPPLY OF VESSELS, HEAT EXCHANGER, STORAGE TANKS. .......................................15 PIPING DESIGN ...................................................................................................................................................15

3. EQUIPMENT AND PRODUCTS. ............................................................ 17 3.1. PROPRIETARY FLARE TIPS. .............................................................................................................................17 3.1.1. HIGH PRESSURE SONIC FLARE TIPS....................................................................................................18 3.1.1.1. 3.1.1.2. 3.1.1.3.

General. ................................................................................................................................................................18 GBA CSF Flare Tip (Sonic). ...............................................................................................................................19 GBA VSF Flare Tip (Sonic). ...............................................................................................................................20

3.1.2. PIPEFLARES...............................................................................................................................................21 3.1.2.1. 3.1.2.2.

General. ................................................................................................................................................................21 GBA PF Series Pipeflare. ....................................................................................................................................22

3.1.3. STEAM ASSIST FLARES. .........................................................................................................................23 3.1.3.1. 3.1.3.2. 3.1.3.3. 3.1.3.4.

General. ................................................................................................................................................................23 GBA GCT - Flare Tip..........................................................................................................................................24 GBA GAJ - Flare Tip. .........................................................................................................................................25 GBA GCT-AJ Flare Tip. .....................................................................................................................................27

3.1.4. AIR FLARES...............................................................................................................................................29 3.1.4.1.

GBA CAF Airflare...............................................................................................................................................29

3.1.5. OFF-SHORE BURNER...............................................................................................................................30 3.1.5.1.

Seafire Burner and Boom. ...................................................................................................................................30

3.2. PURGE EQUIPMENT AND SEALS. ...................................................................................................................31 3.2.1. MOLECULAR SEAL. .................................................................................................................................32 3.2.2. AIR LOCK SEAL. .......................................................................................................................................32 3.2.3. COMPARISION OF MOLECULAR AND AIR LOCK SEALS. ...............................................................33 3.3. WATER SEALS AND KNOCK-OUT DRUMS....................................................................................................34 3.3.1. Water Seal. ...................................................................................................................................................34 3.3.2. Knock-Out Drum. ........................................................................................................................................35 3.4. FLARE PILOT AND IGNITION SYSTEMS. .......................................................................................................36 3.4.1. Flame Front Generator. ................................................................................................................................37 3.4.2. Natural Draft Flame Front Generator. ..........................................................................................................38 3.4.3. CHT High Energy Electric Ignition Pilot .....................................................................................................39 3.4.4. DESI Direct Electric Spark Ignition............................................................................................................40 3.5. STEAM CONTROL AND MONITORING SYSTEMS. .......................................................................................41 3.6. STRUCTURES. .....................................................................................................................................................42 3.6.1. Guy Wire Supported Stacks .........................................................................................................................43 3.6.2. Derrick Supported Stacks.............................................................................................................................44 3.6.3. GBA Demountable Flare..............................................................................................................................45 3.7. TYPICAL P&ID’S..................................................................................................................................................50

GBA PRODUCT MANUAL Rev 2004


4. FLARE RADIATION CALCULATIONS AND TECHNIQUES.......... 52 4.1. 4.2. 4.3. 4.4. 4.5.

RADIATION ISOPLETHS. ...................................................................................................................................52 THERMAL RADIATION PLOT. ....................................................................................................................................53 SINGLE AND MULTI TIP ONSHORE INSTALLATIONS. ...............................................................................54 OFFSHORE INSTALLATIONS............................................................................................................................55 HORIZONTAL BURNPIT INSTALLATIONS. ...................................................................................................56

5. COMPANY PROFILE............................................................................... 58 5.1. GENERAL. ............................................................................................................................................................58 5.2. EXPERIENCE PROFILE OF KEY ENGINEERING STAFF..................................................................................................58 5.3. FABRICATION SHOP CAPABILITIES...............................................................................................................61 5.3.1. Fabrication Plant Address. ...........................................................................................................................61 5.3.2. Available area. .............................................................................................................................................61 5.3.3. Workforce. ...................................................................................................................................................61 5.3.4. Tools and Plant.............................................................................................................................................62 5.3.5. General.........................................................................................................................................................62 5.3.6. Welding........................................................................................................................................................62 5.4. SUB-SUPPLIERS. .................................................................................................................................................63 5.4.1. Fabrication. ..................................................................................................................................................63 5.4.2. Electrical / Ignition Panels. ..........................................................................................................................63

6. LIST OF INDUSTRIAL CODES AND STANDARDS USED BY GBA.66 7. MAIN CUSTOMER LIST. ........................................................................ 68 8. INTERNATIONAL USERS REFERENCE LIST. ................................. 70



ONSHORE FLARE SYSTEMS A GENERAL DISCUSSION.



1. ONSHORE FLARE SYSTEMS. Onshore Flare Systems generally operate at pressures near atmospheric and are often used to flare gases that produce smoke when burnt in any quantity. This basically encompasses flares on refineries, chemical plants, oil and LPG terminals, etc.

1.1. INTRODUCTION. The flare is a key component of the closed emergency release system in a refinery or chemical plant. Emergency releases originating from safety valves, vapour blow downs, process stream diversion and equipment drainage, which cannot be discharged directly to the atmosphere for reasons of safety or pollution control, are routed through closed systems to a blow down drum where liquids and vapours are separated. The flare provides a means of safe disposal of the vapour streams from these facilities, by burning them under controlled conditions to ensure that adjacent equipment or personnel are not exposed to hazard. In addition pollution control and public relations requirements must be met. A typical refinery flare will use several utilities when in operation power, steam, fuel gas. The careful design, operation and maintenance of the flare system can minimise the costs of these expensive utilities.

1.2. FLARE TYPES AND APPLICATION. In general there are three types of flares available for onshore use:

a) The elevated flare; b) The groundflare; c) The burn pit flare. Although the three basic designs differ considerably in required capital and operating costs, selection is based primarily on pollution and public relations considerations, i.e. smoke, luminosity, air pollution, noise and available space.

a) Elevated Flares. Elevated flares are the simplest and most widely used, offering safe and efficient combustion of waste gases with varying degrees of smokeless burning. By the use of steam injection and effective tip design, heavy hydrocarbons can be burnt smokelessly. Steam injection, used to reduce smoke pollution, introduces a source of noise, and a compromise between smoke reduction and noise is usually necessary. If correctly designed the elevated flare provides the best dispersion characteristics for malodorous and toxic combustion products and is the general choice for either total flare loads, or for handling over-capacity releases in conjunction with a ground flare. For most applications, the elevated type is the only acceptable means of flaring "dirty gases", i.e. gases high in unsaturates, hydrogen sulphide or those that have highly toxic combustion products. Structures. Three types of support methods for elevated flares are used:



a) Guyed - this type of structure is usually the least expensive to build but in some cases the guy wires result in restrictions on the use of adjacent land in addition to normal spacing restrictions. b) Derrick - this type of structure is well suited for tall structures subject to strong winds or where large thermal ranges are expected. The structure can be designed such that the flare stack may be demounted for maintenance purposes, removing the requirement for plant shutdown if the flares are arranged as duty/standby. c) Self-Supporting - this type of structure is designed so that the flare riser pipe has no lateral structural support. For short flares, this is the least expensive system to erect and maintain. b) Groundflares. Various designs of proprietary ground flare are available. Smokeless operation can generally be achieved (with or without assist media depending on design), with essentially no noise or luminosity problems, provided that the design rate to the flare is not exceeded. However, since the flame is near ground level, dispersion of stack releases needs to be carefully considered. The ground flare is suitable for "clean" gases (i.e. where toxic or malodorous concentrations are unlikely to be released through incomplete combustion or as combustion products), offers very low noise characteristics and reduces the visual effect of a flame, which is concealed at all times. It should not be used in locations upwind of adjacent residential areas. Generally, it is not practical to install a ground flare large enough to burn the maximum release load, and the usual arrangement is in combination with an elevated relief flare. The latter is normally provided with steam injection, but smoke may be accepted during the small number of major releases.

c) Burn Pit Flares. The burn pit is of simple construction, with low capital and operating costs, and can handle liquid as well as vapour hydrocarbons. The sizing of pit flare systems is essentially the same as for pipe flares without the knockout drum. The flare header should slope down to the pit to allow full drainage of liquids. The flare pit will be sized for the largest flame length, taking account of thermal rise, and the predicted volume of liquids to be held. The pit should slope away from the flare tip and the pit orientation should minimise wind blowing into the flare tip. Remotely ignited pilot burners are essential for the protection of personnel due to the possibility of unburnt hydrocarbons remaining within the pit bund. There is no means of controlling emission from a low-pressure flare and as such their use should be limited.



1.3. FLARE SYSTEM DESIGN. Flare Capacity and Sizing. Flare systems are designed to handle the largest vapour release from safety valves, vapour blow downs and other emergency relief systems. Normally the flare will be sized following a plant hazard analysis and is a function of maximum allowable backpressure on safety valves and other sources of release into the emergency systems. Flare design must consider the pressure drop through the relief headers, knockout drums, flare header, seal drum, stack riser, purge seal and flare tip. In accordance with API RP 521 recommendations, tip exit velocity at maximum relief should be limited to 0.5 Mach to ensure stability and limit excessive noise. For pressure drops through proprietary flare tips and allowable exit velocities, which may be greater than 0.5 Mach, flare vendors should be approached. For some gas compositions exit velocity may need to be restricted due to high flame speed (hydrogen) or low heating value gases (ammonia and gases rich in inert).

Flare Location and Height. The location and height of an elevated flare will be predominantly based on radiation. In some instances dispersion of toxic gases from a lit or unlit flare may be controlling. Radiation limits are generally based on personnel tolerance rather than equipment tolerance to heat, as the former levels are considerably lower. In lower latitude regions, solar radiation will need to be considered as an additive to flare radiation and hence flare height or sterile boundary will be increased compared with plants in higher latitudes. The generally accepted radiation limits are: 500 Btu/h.ft2 (1,6 kW/m2) for continuous working And 1.500 Btu/h.ft2 (4,7 kW/m2) for emergency access only.

1.4. KEY COMPONENTS. The basic components of an elevated flare system can be summarised as follows:

a) b) c) d) e) f) g)

Flare tip; Air ingress seal; Stack riser and structure; Water seal; Knock-out drum; Means to control smoke emissions; Ignition system.

a) Flare Tip. There are a number of different designs of flare tip available: • Pipeflare tips; • Steam flare tips; • High pressure sonic flare tips; • Air blown flare tips.



GBA ENGINEERING AND CONSTRUCTION HAVE A COMPLETE RANGE OF FLARE TIPS TO SUIT ALL CONDITIONS. THESE ARE COVERED EXTENSIVELY WITHIN THIS DOCUMENT. Pipe flares are the most commonly used general-purpose tips, but do not provide any degree of smokeless combustion unless the gas is predominantly methane and has a molecular weight less than 20. For smokeless combustion the simplest and most common type of tip, which uses steam as a smoke suppressant, is the generic 'Crown of Thorns' tip which injects steam through a number of nozzles located on a manifold positioned around the circumference of the tip. Other types use the ejector principle to premix air into the steam through a manifold at the base of the tip. The pre-mixed phase then flows through a number of internal tubes within the tip, emerging to mix co-currently with the flare gas. This type of tip is more efficient than the 'Crown of Thorns', operates with lower noise characteristics and provides a greater extent of smokeless capacity. Where steam is not available, air blown flares will provide a percentage of smokeless burning. The tip incorporates a series of flow vanes designed to maximise the mixing of flare gas and primary air provided by a blower / fan included as part of the flare system. Where the relief gas is at high pressure (mainly available on offshore oil and gas production platforms) the driving force of the gas may be used to promote smokeless combustion at sonic velocities. For turndown conditions, consideration is given to the design of a variable slot tip, which will ensure smokeless combustion at relief rates from maximum to purge.

b) Air Ingress Seals and Purging. Flare systems are subject to potential flashback and internal explosion since flammable vapour / air mixtures may be formed in the stack or inlet piping by the entry of air. The pilot constitutes a continuous ignition source. Flares may be provided with flashback protection, which prevents a flame front from travelling back to the upstream piping and equipment, or may be positively purged with hydrocarbon or inert gas to ensure a non-flammable atmosphere within the stack. The most common cause of a stack explosion is where air has entered the plant and has passed through the flare header as an explosive mixture. Depending on the application and client preference elevated flare stacks may be fitted with a molecular seal (also known as the labyrinth seal) or fluidic seal. The molecular seal uses the density differences between the purge gas and air to produce a barrier against air infiltration. It has become apparent in the last few years that purge rates can be reduced to comparable levels of molecular seals just by using a simple fluidic type seal. This latter type uses the velocity of the purge gas to pick up and carry out any air that diffused into the tip. The use of a velocity seal (GBA type Air Lock Seal) is generally preferred due to its low cost, minimal restriction to flow and its absence of impact on structural design. It is interesting to note that work on tall elevated stacks evaluating the effectiveness of various purge rates, shows that the correlation derived by Husa can significantly underestimate the required purge gas rate in the unlit condition, but it should also be noted that as soon as the purge is lit, oxygen levels measured 6m down the stack fall to near zero, indicating that the infiltrating air is being used in the combustion of the purge gas - probably internally.



c) Stack Riser and Structure. Many varieties of structures have been used for flare stack support, but the most common is the guyed stack, which is generally the lowest cost option. Heights of up to approximately 150m have been successfully employed, although these are few, most refinery stacks being in the 60-100m ranges. A limitation for guyed stacks is the range of process temperature encountered when in service. This variation in temperature will cause the stack to expand and contract with resultant stretching or loosening of the guy wires. A service range of 200 to 300°C is usually limiting in this case. In the event of an excessive temperature variation, a guyed derrick can be used or even a freestanding derrick structure. A structure offering great operational flexibility is the jack-up derrick. This allows flares and risers to be dismounted for replacement and / or repair while a second flare system remains on-line. No plant downtime is necessary. This is a system much favoured by certain operators and is one that GBA are extremely experienced with, having built three of the worlds largest systems (204m) in Antwerp, Belgium.

d) Water Seals. Water seals are used to provide a positive seal against air ingress and flashback, and also to maintain the upstream header at a positive pressure. Water seal drums can either be horizontally or vertically mounted and must be correctly sized to prevent water carryover through the flare stack under normal operating conditions. Under emergency conditions it must be expected that the water will be carried away by the high flare gas velocities. Fast water makeup is therefore important to maintain the seal integrity. A common problem with water seals is one of pulsation caused by water moving from side to side, causing the gas flow to vary periodically with time, (the period is generally about 1 second). This causes the flare flame to rise and fall, and also the flare noise to fluctuate. The internal design of the seal requires considerable attention with a variety of designs put forward by vendors. GBA has had considerable success in eliminating this problem by use of a 'Seebold' baffle and by using a 'saw-tooth' arrangement on the end of the dip leg.

e) Knockout Drums. Knockout drums are designed to remove liquid droplets of excessive size from the gas stream and to return the collected liquid to the process/drain. Sizing to API RP-521 recommendations is generally adequate but the knockout drum should be sited as close as practically possible to the flare stack and should not possess any internals liable to blockage.

f) Steam Control System Accurate control of steam supply to a steam flare is desirable



(i) (ii) (iii) (iv)

To minimise smoke emission; To minimise noise emission; To minimise steam consumption; To avoid over-steaming and subsequent loss of flame.

Traditionally, the steam flow is retied to gas flow and if the composition of the gases is subject to change, a density measurement for ratio correction is also required. These types of systems are of minimal success because flow measurement is difficult due to the low velocity of the gases. The density measurement is equally difficult because the gases are sometimes corrosive and always dirty. Maintenance and downtime on this type of system is very high. Because of these problems, it is typical to find the steam valve manually loaded to 60% or higher, to protect against the flare smoking, which results in a tremendous waste of expensive steam. Closed circuit television is sometimes used for steam control. A television camera is installed in the field, aimed at the flare tip with a screen in the control room for operator viewing. The unit operator should occasionally glance at the screen and manually adjust the steam flow. Since the operator may not be checking the operation of the flare continuously, manual steam flow is normally much greater than required, to insure that small upsets do not create a smoking condition. A number of optical infrared monitors are available which will provide a fully automatic closed-loop control of steam to avoid smoke formation. The infrared monitor used by GBA measures the radiant flux density from hot gaseous combustion products and from particles of carbon. The monitor measures the flare's tendency to smoke and hence can ensure steam is delivered before smoke formation. The advantages of an infrared flame monitor are:

Control is not affected by flare gas composition and discharge velocity; Fast response time; No gas flow or density device required; No component exposed to flare gas stream; Very low maintenance at accessible location.

g) Pilot Ignition System Almost without exception, flare pilot ignition is performed by using a flame front generation system. This method involves filling a small-bore pipe, which runs from the flame front generator panel to the flare tip, with a combustible gas / air mixture. The mixture is ignited by a spark in an ignition chamber on the panel, generating a flame front which travels to the pilot and lights it at the tip. This technique is well known, and established throughout the industry. However its performance is affected by a number of factors which combine to present problems in the field making it unreliable i.e.



(i) Flame front lines always collect large quantities of water, which require draining before ignition; (ii) Changes in fuel gas compositions and the use of wet air conspire to defeat operators; (iii) Long term pipe corrosion and lack of maintenance reduce the probability of a good ignition. Electric pilot ignition systems have been developed to overcome the problems of the flame front ignition system. GBA have developed the CHT System using a direct electric ignition flare pilot. Using this technique, the pilot flame is lit directly from a High Energy spark generated adjacent to the pilot nozzle. The ignitor can be powered from any available mains AC supply or even from low voltage DC supplies and is offered for use in either safe or explosion proof classified areas.

Groundflares In most cases the economics of providing a groundflare sized to handle the entire release from the largest design contingency are prohibitive, due to the low frequency of occurrence of such major releases. Instead it is designed to handle a proportion of the flow so that releases up to this level will be smokeless and non-luminous. This will normally cover a large proportion of releases in a typical plant, but variations on this sizing basis may be dictated by considerations of the number and type of upstream process units, type and probability of major release contingencies, atmospheric pollution restrictions and cost of the flare facilities. An over-capacity line to an elevated flare is provided to handle the excess flow when the flaring rate exceeds the capacity of the groundflare. The over-capacity line and flare is normally designed to handle the entire maximum flow such that it can allow the groundflare to be shut down for maintenance. In this arrangement the water seal described above acts as a "diverter valve" such that the gas will divert to the groundflare up to a predetermined pressure, set by the water height. Groundflares must be considered as a whole and not as a collection of parts. That is to say the enclosure, the burners, the air distribution, the location and the wind fence must all be designed to work in combination. It is pointless to have a highly efficient burner if the air distribution system does not succeed in supplying air to the burner.

Air Management System. Perhaps the key to good groundflare design is the overall air management system to draw air to the flare base, allowing the burners to induce an even flow, distributed uniformly. Basic vertical wind fences provide a degree of protection from wind blowing through the open base of the groundflare. This design however, produces eddies and uneven distribution across the combustion enclosure. Extensive wind tunnel testing has resulted in a wind fence of an inclined and louvered nature. The wind fence ensures even air distribution across the enclosure and control air flow to limit NOX formation.



Burner System. Most groundflare designs have an array of burners, which are staged to ensure even and complete combustion. Staging control is based on header pressure. Smokeless combustion often requires assist media such as steam or forced draft air at the burner head. The burner system utilised by GBA is a proprietary design, which does not require assist media. It produces a stable flame and provides for low emissions and low radiation, eliminating maintenance problems associated with cracking of hydrocarbons within the gas manifolds. Enclosure. Combustion takes place within a refractory lined enclosure of rectangular or circular section. The height is dependent upon the required combustion volume to ensure flames stay within the enclosure. Refractory lining will either be castable type or ceramic fibre blanket, the latter being preferred following extensive trials. The enclosure not only retains the flame from a visual point of view but also provides a barrier to noise. As such groundflares can be located very close to the plant with minimum sterile area.



PRODUCT LISTING AND ENGINEERING CAPABILITIES.



2. PRODUCT LISTING AND ENGINEERING CAPABILITIES. 2.1. GENERAL. GBA employs over 40 personnel at its offices in London, Milan, and Houston comprising process, mechanical, structural and instrument engineers, CAD draughtsmen, QA/QC managers, inspectors and support staff in addition to qualified welders, fitters, construction crew and supervisors based at our fabrication plant in Parma. Each individual is highly qualified in their own field of expertise, and collectively, all employees ensure that GBA can offer a complete "turn-key" package covering process design, engineering, procurement, fabrication, project management, erection/ construction, commissioning and maintenance of our total product range as further described in this section. GBA has the capability to perform design and engineering using the most up-to-date networked AUTOCAD facilities and E-mail service, a project management department with international procurement experience, Quality Control management and inspectors all dedicated to ensuring quality and timely delivery of equipment.

2.2. DESIGN CAPABILITIES. GBA provides a total "turn-key" project responsibility ensuring minimum cost and minimum risk to our clients. This responsibility includes, but is not limited to:-

a) b) c) d) e) f) g) h) i) j) k) l) m) n)

Process design Engineering (mechanical, structural, instrument, control, electrical) Engineering draughting, CAD design Project management Procurement Planning Fabrication QA/QC Inspection Transportation/Shipping Construction/Erection Pre-commissioning/Commissioning Maintenance After sales service

2.3. DESIGN AND SUPPLY OF INTEGRATED FLARE SYSTEMS. a) b) c) d) e) f) g)

Derrick supported flares Derrick supported demountable flares Guy wire supported flares Self supported flares Enclosed ground flares Towers and booms for offshore flare installations Burn-pit flares



2.4. DESIGN AND SUPPLY OF FLARE TIPS AND BURNERS. a) b) c) d) e) f) g) h)

Pipe flare tips Steam assisted flare tips for smokeless combustion Air assisted flare tips for smokeless combustion Sonic high pressure flare tips Liquid/Condensate flare tips and burners LNG flare tips Ground flare burners Vent tips with high dispersion characteristics

2.5. FLARE CONTROL AND SAFETY SYSTEMS. a) b) c) d) e) f) g)

Ignition equipment Automatic Steam Control Purge equipment Water seal drums and instrumentation Knock-out drums and instrumentation Pumping skids Radiation and noise reduction systems

2.6. TECHNICAL DESIGN CONSULTANCY SERVICES. a) b) c) d) e) f) g) h) i) j)

Structural and mechanical design/drawings of derrick structures, towers and booms Maintenance and mechanical handling systems for both onshore and offshore applications Process and safety audits Radiation calculations and isopleths Thermal design and temperature profiles Noise calculations Emission calculations for both flare and vent systems Flare deck radiation/noise attenuation Design and development of detailed fabrication/erection drawings Erection and construction studies

2.7. INSTALLATION/ERECTION. GBA employ their own construction and installation crew and will provide all labour, workforce and plant necessary to erect equipment supplied by GBA or others.

2.8. COMMISSIONING. GBA employ their own team of engineers capable of providing on-site services for all your precommissioning and commissioning requirements.

2.9. MAINTENANCE. GBA employ their own team of engineers, experienced and qualified to inspect existing plant and make recommendations on the need to repair, replace or continue to use equipment.



Our engineers will be pleased to undertake studies for replacing our own or competitors equipment and will be pleased to undertake all work necessary to change-out flare tips using our own labour and plant. GBA will also be pleased to conduct guy wire inspections on existing stacks and re-tension wires if it is felt necessary as part of an on-going maintenance program.

2.10. DESIGN AND SUPPLY OF STEEL STRUCTURES. a) b) c) d) e) f) g)

Steel structures for bridges Flying bridges Industrial structures Frameworks for steel buildings Lattice towers and masts for electrical lines and power cables Lattice towers and masts for telecommunications Design and development of detailed fabrication/erection drawings

2.11. DESIGN AND SUPPLY OF VESSELS, HEAT EXCHANGER, STORAGE TANKS. a) Process, thermal and mechanical design with development of engineering drawings and specifications b) Development of detailed fabrication drawings c) Inspection and supervision

2.12. PIPING DESIGN a) Piping process sizing including internal lining, sizing for temperature or other process requirements b) Piping layouts c) Stress analysis and support definition d) Fabrication isometrics e) General piping studies



EQUIPMENT AND PRODUCTS.



3. EQUIPMENT AND PRODUCTS. 3.1. PROPRIETARY FLARE TIPS. GBA offer a comprehensive range of proprietary flare tips designed to handle the safe and efficient relief / disposal of gases discharged either from crude-oil production fields, gas fields, refineries, chemical and petrochemical plants or as by-products in Industry. GBA's philosophy is to ensure that the equipment is designed and fabricated to withstand the most arduous operating conditions of service, does not deteriorate in severe climatic conditions to which it is exposed, and operates at full efficiency within the levels of safety acceptable to the industry imposed by local authorities and environmental organisations. GBA's flares encompass a complete range of applications from low volume, low pressure to high volume, high pressure operation throughout the Oil and Gas Industry and are further described within this section.

a. High Pressure Sonic Flare Tips. b. Pipeflare Tips. c. Steam Assist Flare Tips. d. Air Flares.



3.1.1. HIGH PRESSURE SONIC FLARE TIPS. 3.1.1.1. General. The safe disposal of gas from emergency depressurisation or blowdown operations is a major consideration for the designers of offshore oil and gas production platforms. Consideration of the flare or vent location must revolve around incident radiation on various parts of the platform, the flame path during changing process conditions, the risk of liquid carryover, and the gas plume in the event of flame-out. Based on the above, the flare tip selection is extremely important, and care must be taken in the evaluation of the type of technology for a particular application. GBA Sonic Flare Tips offer:

Low Radiation Characteristics : using single or multi jet configurations operating at high exit velocities to ensure efficient combustion by good air entrainment. Stability : achieved by using multiple jets and correctly designed and positioned pilot burners. Liquid Burning Capacity : any entrained liquid is atomised at high exit velocities and discharged from the jets co-axially with the relief gas. The residence time of the atomised liquid is sufficient to ensure complete combustion. No Blockage : single or multi jet open pipe configurations eliminate the possibility of blockage due to thermal distortion of the tip or debris carried in the relief gas stream. There are NO possibilities of mechanical blockage unlike other sonic flare technologies. Low Noise Characteristics : As gas discharges parallel with the flare tip, noise is directed away from the installation. Good Turndown Characteristics : Flexibility of operation is achieved from maximum relief to turndown without the use of mechanical devices. Process conditions from plant start-up through to emergency blow down can be accommodated using a single flare tip. Purge gas velocity increases with flare diameter. Therefore utilising multi-nozzles requires a lower purge than a single tip of equivalent area. Due to the high velocities used, the total area and therefore purge requirements is significantly reduced. Resistance to Wind : Due to the aeration of the flames and high gas velocities, deflection of the flame due to wind effect is slight.



3.1.1.2. GBA CSF Flare Tip (Sonic). The GBA CSF is a single or multi-nozzle sonic high pressure flare tip designed to give superior performance where low thermal radiation and smokeless combustion is required. Its unique design of sonic nozzle channels the gas through a narrow annulus thereby maximising the gas / air interface and consequently entraining more CSF primary combustion air than Nozzles conventional tips. This translates into a highly pre-mixed flame that radiates Pilot Nozzle less and will be smokeless for a greater number of applications and flow conditions. Every effort has been made to ensure longevity in service and to this end the critical parts are all fabricated from thick wall heat resisting alloy. In addition, a slatted windshield works to minimise flame draw-down in windy conditions. For certain applications the GBA CSF flare tip is designed with multiple sonic nozzles. The use of multiple nozzles increases the gas / air interface area even further thus improving the overall flare tip performance in terms of even lower emitted radiation and shorter flame lengths. Critical items such as the flame retention lugs, pilot heads and all welded attachments in the heat affected zones are fabricated from high nickel alloys (310S) and are subject to rigorous and thorough inspection during manufacture.

Wind Shields

Ignition Manifold

Pilot Manifold

Inspirator Assembly

Pilot

Ignition

HP Gas

The tip is equipped with G-100 pilot Inlet Inlet Inlet burners that provide a constant and reliable source of ignition. Each pilot consists of a special high stability burner nozzle and a cast inspirator assembly designed to ensure correct secondary air requirements. Pilot gas and flame front ignition can be supplied either through individual lines or through distribution manifolds located at the base of the tip.



3.1.1.3. GBA VSF Flare Tip (Sonic). The GBA VSF is a variable slot sonic high pressure flare tip designed to give superior performance where low thermal radiation and smokeless combustion is required under high turndown conditions. Its unique design of sonic nozzle channels the gas through a narrow annulus thereby maximising the gas/air interface and consequently entraining more primary combustion air than conventional Gas Slot tips. This translates into a highly pre-mixed Pilot flame that radiates less and will be smokeless Nozzle for most applications and flow conditions. Every effort has been made to assure longevity in service and to this end the critical parts are all fabricated from thick wall heat resisting alloys and in addition a slatted windshield Inner works to minimise flame draw-down in windy Wind Stack conditions. Shield The key to the GBA VSF's ability to deliver optimum performance over a wide range of operating flow rates lies in its unique ability to automatically vary the gas discharge slot width in response to changes in the flare gas flow rate. The GBA VSF is therefore not limited to a single slot geometry and adapts to a much wider range of operating conditions. At low flow rates the slot is positioned at its minimum setting, causing the back pressure to rise sufficiently to produce high discharge velocities which promote turbulent pre-mixed smokeless, low radiation combustion. The slot is normally configured to remain at minimum setting until a pressure of approx 0.7 barg is reached.

Spring Stack Ignition Manifold

Air Lock Seal

Inspirator Assembly Pilot Manifold

Pilot

Ignition

At this point, the slot starts to open linearly Inlet Inlet with increasing pressure until the maximum Gas Inlet slot is achieved at approx 1.80 barg. Once the maximum slot position is achieved, the tip behaves as a fixed slot version and gas flow increases directly proportional to the absolute inlet pressure (upstream density). Critical items such as the flame retention lugs, pilot heads and all welded attachments in the heat affected zones are fabricated from high nickel alloys (310S) and are subject to rigorous and thorough inspection during manufacture. The GBA VSF tip is fitted with G-100 pilot burners that provide a constant and reliable source of ignition. Each pilot consists of a special high stability nozzle cast in stainless steel material, gas/lines and cast inspirator assembly. Pilot gas and flame front ignition can be supplied either through individual lines or through distribution manifolds located at the base of the tip.


VSF-12/3 Flare Tip Flow vs Pressure Curve: Low Flow, High MW 12000

10000

Flow kg/h

8000

6000

4000

2000

0 0.0

0.1

0.2

0.3

0.4

0.5

Pressure barg MW= 58.08 Temp= 0.0°C

0.6

0.7

0.8

VSF-12/3 Flare Tip Flow vs Pressure Curve: Case 2 120000

100000

Flow kg/h

80000

60000

40000

20000

0 0.0

0.5

1.0

1.5 Pressure barg MW= 20.65 Temp= -40.0°C

2.0

2.5

3.0


3.1.2. PIPEFLARES. 3.1.2.1. General. Traditionally, the pipeflare has been operated in the majority of flaring applications where hydrocarbon gas streams are burnt and where there are no restrictions of the production of smoke. Smoke will be generated to varying degrees depending on the molecular weight of the relief gas - the heavier the hydrocarbon, the more smoke will be generated. The main advantage of the pipeflare is its simplicity, robust construction, flexibility of operation and economy. Its applications can be found for duties associated with the following:

Offshore Oil and Gas Platforms Refineries Petrochemical Sites Production Fields Two phase combustion - horizontal burn pits.



3.1.2.2. GBA PF Series Pipeflare. The GBA PF flare tip provides a flexible method of low pressure, high volume waste gas disposal utilising a well proven technology that ensures a safe and efficient means of combusting relief flow rates from maximum emergency conditions to turndown. Flame stability over the entire operating range is achieved by incorporating a series of flame retention lugs located around the periphery of the tip. This device stabilises the flame by Flame Retention creating a zone of re-circulating gas Lugs immediately downstream of the lugs and helps prevent lift-off. This together with the auxiliary stabilising effect of the purpose Pilot Nozzle designed pilots ensures maximum reliability under all wind conditions. The basic tip is of robust construction, fabricated from heat resistant stainless steel selected to avoid the requirement for additional refractory lining. Critical items such as the flame retention lugs, pilot heads and all welded attachments in the heat affected zones are fabricated from high nickel alloys (310S) and are subject to rigorous and thorough inspection during manufacture. To further enhance its operating life external wind deflectors are attached to the tip, designed to eliminate the low pressure zone created on the downwind side of the flare, which can cause flame impingement. These deflectors are fabricated in the form of slatted strakes and are manufactured from 310S stainless steel. The tip is equipped with G-100 pilot burners that provide a constant and reliable source of ignition. Each pilot consists of a special high stability burner nozzle, a cast inspirator assembly designed to ensure correct secondary air requirements, pilot gas and pilot ignition lines all fabricated from stainless steel.

Wind Shield

Ignition Manifold

Air Lock Seal

Inspirator Assembly Pilot Manifold

Ignition Inlet

Pilot Gas Inlet

Gas Inlet

Pilot gas and flame front ignition can be supplied either through individual lines or through distribution manifolds located at the base of the tip.



3.1.3. STEAM ASSIST FLARES. 3.1.3.1. General. Most hydrocarbon containing relief gases tend to produce smoke when burnt unless sufficient oxygen is introduced into the zone of combustion. In particular, very low pressure gas streams and gases containing unsaturates are particularly prone to smoking due to the cracking and polymerisation that takes place in the core of the flame where flame temperatures are high and where there is insufficient oxygen for complete combustion. Smoke formation is often associated with high thermal radiation levels. Depending on the composition of hydrocarbon gas to be burnt, the extent of smokeless combustion required and the availability of steam as the medium to promote smokeless combustion, there are several types of flare tip available from GBA to meet your requirement. The simplest and most common type is that which features on upper steam manifold only, the GBA GCT series. This uses a number of injector nozzles located on a manifold positioned around the tip circumference to inject steam at high pressure directly into the flame. For applications where maximum efficiency and reduced emission is required, then it is preferable to use a tip that utilises internal steam/air tubes to improve performance. This type of tip pre-mixes air into the steam flow which then flows through a number of internal tubes within the tip emerging to mix co-currently with the flare gas, the GBA GAJ series. This method of injecting steam is more efficient than the upper ring of jets, is less noisy and provides a greater smokeless capacity. GBA offer a further extension to the smokeless capacity, which may be achieved by incorporating both upper, and lower steam injection facilities on the flare tip the GBA GCT-AJ series.



3.1.3.2. GBA GCT - Flare Tip. The GBA GCT flare tip provides a flexible method of low pressure, waste gas disposal utilising a well proven technology that ensures a safe and efficient means of combusting relief flow rates from maximum emergency conditions to turndown. Flame stability over the entire operating range is achieved by incorporating a series of flame retention lugs located around the periphery of the tip. This device stabilises the flame by creating a zone of re-circulating gas immediately downstream of the lugs and helps prevent blow-off. This together with the auxiliary stabilising effect of the purpose designed pilots ensures maximum reliability under all wind conditions. Smokeless combustion is achieved with the GBA GCT flare tip through an upper steam manifold and a set of steam injection nozzles located around the circumference of the tip. These multi port nozzles are used to inject steam into the flame envelope with a degree of swirl, thus creating turbulence and inducing air into the flame. Steam Retention Pilot The steam also acts to cool the flame, thus Nozzle Lugs Head preventing thermal cracking of hydrocarbons and consequent smoke production. In Wind addition, a centre steam injector is used to Shield break up the central core of gas and to prevent burn-back. This type of steam injection is exceptionally simple to use and very flexible. Upper It will work effectively using steam of Steam Manifold virtually any quality/pressure. The basic tip is of robust construction, fabricated from heat resistant stainless steel selected to avoid the requirement for additional refractory lining. Critical items such as the flame retention lugs, pilot heads and all welded attachments in the heat affected zones are fabricated from high nickel alloys (310S) and are subject to rigorous and thorough inspection during manufacture. To further enhance its operating life and to optimise the operation of the steam nozzle, external wind deflectors are attached to the tip, designed to eliminate the low pressure zone created on the downwind side of the flare, which can cause flame impingement. These deflectors are fabricated in the form of slatted strakes and are manufactured from 310S stainless steel.

Centre Steam Nozzle Air Lock Seal Inspirator

Steam

Main Gas Inlet

Pilot Gas Flame Front

Each tip is equipped with G-100 pilot burners that provide a constant and reliable source of ignition. Each pilot consists of a special high stability burner nozzle, a cast inspirator assembly designed to ensure correct secondary air requirements, pilot gas and pilot ignition lines all fabricated from stainless steel. Pilot gas and flame front ignition can be supplied either through individual lines or through distribution manifolds located at the base of the tip.



3.1.3.3. GBA GAJ - Flare Tip.

The lower steam manifold supplies a number of internal annular jet air inducers, which use the steam pressure to inspirate large quantities of air into the internal mixing tubes. The resulting steam / air mixture is ejected from the tubes into the core of the flame envelope where it mixes with the waste gases creating a turbulent smokeless flame.

Steam / Air Mixture

The GBA GAJ flare tip provides a flexible method of low pressure, high volume waste gas disposal utilising advanced technology that ensures a safe and efficient means of combusting relief flow rates from maximum emergency conditions to turndown. Flame stability over the entire operating range is achieved by incorporating a series of flame retention lugs located around the periphery of the tip. This device stabilises the flame by Retention Lugs creating a zone of re-circulating gas Pilot immediately downstream of the lugs Head and helps prevent blow-off. This together with the auxiliary stabilising effect of the purpose designed pilots Slatted ensures maximum reliability under Windshield all wind conditions. Smokeless combustion is achieved with the GBA GAJ through a lower steam manifold and a centre steam nozzle.

Lower Steam Manifold

Annular Steam Jet

This method of steam injection is not only more efficient than the GCT type, but it inherently generates less noise at source and also permits the use of an integral noise muffler which attenuates noise levels still further. A centre steam connection is provided to inject steam into the very centre of the flame core and also to act as cooling medium for the tip internals.

Centre Steam Lower Steam

Main Gas Inlet

Pilot Gas Flame Front

The basic tip is of robust construction, fabricated from heat resistant stainless steel selected to avoid the requirement for additional refractory lining. Critical items such as the flame retention lugs, pilot heads and all welded attachments in the heat affected zones are fabricated from high nickel alloys (310S) and are subject to rigorous and thorough inspection during manufacture. To further enhance its operating life, external wind deflectors are attached to the tip, designed to



eliminate the low pressure zone created on the downwind side of the flare, which can cause flame impingement. These deflectors are fabricated in the form of slatted strakes and are manufactured from 310S stainless steel. The tip is equipped with G-100 pilot burners that provide a constant and reliable source of ignition. Each pilot consists of a special high stability burner nozzle, a cast inspirator assembly designed to ensure correct secondary air requirements, pilot gas and pilot ignition lines all fabricated from stainless steel. Pilot gas and flame front ignition can be supplied either through individual lines or through distribution manifolds located at the base of the tip.



3.1.3.4. GBA GCT-AJ Flare Tip.

Smokeless combustion is achieved with the GCT-AJ flare tip through the combined operation of an upper steam manifold (GCT) and lower steam manifold (GAJ), with a greater smokeless capacity than either the GCT tip or the GAJ tip.

Steam / Air Mixture

The GBA GCT-AJ flare tip provides a flexible method of low pressure, high volume waste gas disposal utilising advanced technology that ensures a safe and efficient means of combusting relief flow rates from maximum emergency conditions to turndown. Flame stability over the entire operating range is achieved by Steam Nozzle Retention Lugs Pilot incorporating a series of flame retention lugs located around the Head periphery of the tip. This device stabilises the flame by creating a Wind zone of re-circulating gas Shield immediately downstream of the lugs and helps prevent blow-off. This together with the auxiliary stabilising effect of the purpose Upper designed pilots ensures maximum Steam reliability under all wind Manifold conditions.

Lower Steam Manifold

Annular Steam Jet

This ensures greater flexibility over the complete operating range with regards to turndown and smokeless combustion at lower rates whilst maintaining low noise and efficient burning characteristics. It is preferable to primarily use the lower steam injection system, therefore steam control valving is often arranged so that the lower manifold valve is opened first and the upper manifold only opened if necessary.

Centre Steam

Main Gas The lower steam manifold supplies Upper Lower Pilot Gas Inlet a number of internal annular jet air Steam Flame Front inducers, which use the steam pressure to inspirate large quantities of air into the internal mixing tubes. The resulting steam / air mixture is ejected from the tubes into the core of the flame envelope where it mixes with the waste gases creating a turbulent smokeless flame. This method of steam injection is not only more efficient than the GCT type, but it inherently generates less noise at source and also permits the use of an integral noise muffler which attenuates noise levels still further.



The upper steam manifold increases the overall smokeless capacity through the use of an upper steam manifold and a set of steam injection nozzles located around the circumference of the tip. These multi port nozzles are used to inject steam into the flame envelope with a degree of swirl thus creating turbulence and inducing air into the flame. The steam also acts to cool the flame thus preventing thermal cracking of hydrocarbons and consequent smoke production. A centre steam connection is provided to inject steam into the very centre of the flame core and also to act as cooling medium for the tip internals. The basic tip is of robust construction, fabricated from heat resistant stainless steel selected to avoid the requirement for additional refractory lining. Critical items such as the flame retention lugs, pilot heads and all welded attachments in the heat affected zones are fabricated from high nickel alloys (310S) and are subject to rigorous and thorough inspection during manufacture. To further enhance its operating life, external wind deflectors are attached to the tip, designed to eliminate the low pressure zone created on the downwind side of the flare, which can cause flame impingement. These deflectors are fabricated in the form of slatted stakes and are manufactured from 310S stainless steel. The tip is equipped with G-100 pilot burners that provide a constant and reliable source of ignition. Each pilot consists of a special high stability burner nozzle, a cast inspirator assembly designed to ensure correct secondary air requirements, pilot gas and pilot ignition lines all fabricated from stainless steel. Pilot gas and flame front ignition can be supplied either through individual lines or through distribution manifolds located at the base of the tip.



3.1.4. AIR FLARES. 3.1.4.1. GBA CAF Airflare. The GBA CAF range of flare tips is designed to provide for the smokeless combustion of low pressure gases where no process steam is available. Smoke is produced as a result of cracking and polymerisation at high flame temperatures when there is insufficient oxygen for complete combustion. Adequate aeration of the combustion zone reduces smoke which is achieved through the injection of primary air at the flare tip periphery, often supplied via a two speed centrifugal fan, located at the base of the stack. Smokeless combustion is promoted by incorporating a series of flow vanes within the tip, designed to maximise the mixing of flare gas and primary air at the point of exit. This mixing also ensures the stability of the main flame under extreme wind conditions and reduces thermal radiation levels at grade.

Pilot Nozzle

Mixing Vanes

Wind Shield

The GBA CAF air flare provides a flexible method of smokeless flaring utilising a well proven technology that ensures a safe and efficient means of combusting relief flow rates from maximum emergency conditions to purge. The tip is fabricated from high heat resistant stainless steel and comprises two concentric pipe sections, which channel primary air and flare gas into a mixing head located immediately below the tip exit. Air is directed over this head and mixes co-currently with the gas introduced into the radial vanes via a branch connection just above the main flare tip mating flange.

Ignition Inlet

Pilot Inlet

Air Inlet

Gas Inlet

The tip is equipped with G-100 pilot burners that provide a constant and reliable source of ignition. Each pilot consists of a special high stability nozzle, and cast inspirator assembly fabricated from stainless steel designed to ensure correct secondary air requirements, pilot gas and pilot ignition lines all fabricated from stainless steel. Pilot gas and flame front ignition can be supplied either through individual lines or through distribution manifolds located at the base of the tip.



3.1.5. OFF-SHORE BURNER. 3.1.5.1. Seafire Burner and Boom. The GBA-SEAFIRE Burner is of well proven design using air as a medium device to atomize the liquid. Smokeless is achieved by direct-water injection into the flame. No fallout and no black carbon particles, thus no pollution and reduced heat radiation. The presence of solid particles in the liquid does not effect burning operations. Flame stability is guaranteed with the fitted INCOLLOY 800 cone. The burner head is installed on a support c/w rotating pivot and allowing rotation of 75° on each side of the boom centerline by using an hand winch from the foot of the boom. The SEAFIRE Burner is installed on a support boom. The support boom is made by tubular and includes the liquid, gas, air, diesel and water lines. The boom includes working platform around burner heads, a gangway for safe circulation along the boom, a base rotating pivot, a set of cables to support and to rotate the boom.

Water Manifold Burner Head Flexible Hoses

Liquid Pilot Gas Air Water Rotating Table

Pilot

Flare Gas

Gas Flare Burner Boom Structure


Pilot


3.2. PURGE EQUIPMENT AND SEALS. Whenever the flare system is on-line, the flare tip, riser and main header must be maintained in a safe condition at all times. GBA recommend the provision of a continuous positive hydrocarbon or inert gas (nitrogen) purge dedicated to the flare under all conditions. Extensive development work by GBA has resulted in equipment designed to reduce purge rates and to provide a positive safeguard to the flare system in the unlikely event that purge gas is lost. Even though a flare system is not necessarily constantly flowing, the flare stack and relief header must be kept in a safe working condition at all times. This is achieved by the use of a continuous minimum flow of gas designed to prevent air being drawn into the flare system via the flare tip, or otherwise. This is known as the purge gas flow. Without a special flare seal device fitted the purge gas flow would need to have a velocity of between 0.3 to 0.6 m/sec to be effective. For a large diameter stack this can represent a significant amount of gas. To minimise this requirement, it is customary to use a proprietary seal device in the flare system located within, or close to, the flare tips.

There are two main types of gas seal currently available: i) The labyrinth type – (Molecular Seal) ii)The fluidic type – (Air Lock Seal) Both are installed immediately below the flare tip and both will prevent air ingress into the flare system provided a continuous purge gas is available.



3.2.1. MOLECULAR SEAL. The Molecular Seal works by relying on the density difference between the purge gas and air. When the purge gas is lighter than air it forms a gas rich zone at the top of the seal that air cannot penetrate, conversely when the purge gas is heavier than air the seal is formed at the base of the device.

Outlet

In this way only a very low continuous purge flow is necessary to maintain conditions within the seal. A unique advantage of the molecular seal is that it will maintain safe conditions in the upstream riser for several hours in the event of a loss of purge gas.

Drain

Hand Hole

Inlet

3.2.2. AIR LOCK SEAL. The Air Lock Seal (ALS) is a frustro-conical device, which is located as an integral part of the flare tip, welded within the main body of the tip just above the main flange. With all flare tip operations, under low relief conditions, air will slowly diffuse down the inside walls of the tip. The Air Lock Seal design acts to locally increase the velocity of purge gas through the seal, thereby moving any air back out of the tip. The Air Lock Seal is of simple rugged construction and has no moving parts, requiring the absolute minimum of maintenance.


Air Lock Seal


3.2.3. COMPARISION OF MOLECULAR AND AIR LOCK SEALS. 1)The Molecular Seal prevents the ingress of air into the main flare system for a period of 2-4 hours (in the event of purge gas failure) due to the buoyancy effect discussed earlier. The Air Lock Seal has no hold-up capacity, therefore if purge fails, then the system is rapidly exposed to air ingress. 2)The Molecular Seal requires a purge rate of 0.003 m/sec. The Air Lock Seal requires a purge rate of approximately 0.012 m/sec (these are both based on flare tip exit area). Whilst the Molecular Seal requires a lower rate, the decrease could result in the flame burning within the flare tip reducing life time. 3)The Air Lock Seal has the following advantages: simple, open free path to atmosphere; no plugging; easy to install; offers no wind loading to the support structure. The Molecular Seal is heavy and adds considerably to the overall system weight increasing structural loads and increasing costs of the riser; no maintenance. If the Molecular Seal corrodes or is blocked, it has to be replaced requiring complete system shutdown; no drainage or corrosion problems. The Molecular Seal has the potential to corrode at its base and within its drain line, especially with sour gas relief; very low capital and installation costs. The Molecular Seal is expensive due to its size and complicated fabrication of the internal baffle arrangements. An extra drain line is required to grade. A full 360° inspection platform is also required for access to the drain and hand holes at the base of the Molecular Seal; can be used in a horizontal position i.e. burn pits and angled flaring for offshore applications. The Molecular Seal can only be used vertically. Summary. The Air Lock Seal is a simple low cost device with significant technical and commercial advantages over the Molecular Seal as described above. The use of Molecular Seals is quite uncommon now, as industry has recognised that they create more problems than they solve. Indeed the offshore oil production industry (North Sea – offshore UK/Norway/ Denmark) without exception uses Air Lock type seals instead of Molecular Seals due to structural and weight saving advantages of great significance in the design of offshore production facilities where weight and cost is at a premium.



3.3. WATER SEALS AND KNOCK-OUT DRUMS. Water Seals and / or Knock-Out Drums may be designed as vertical vessels, in which case they can be incorporated at the base of the flare system, or as horizontal vessels located at a reasonable distance from the flare. It is however advisable to locate the vessels as close to the stack as possible to avoid condensate accumulation in the header between the drum and the flare.

3.3.1. Water Seal. The Water Seal provides a positive means of flash-back prevention in addition to enabling the system header to operate at a slight positive pressure at all times. This is of use when an elevated flare is used in combination with another flare, or with a flare gas recovery system. The Water Seal vessel is fitted with a special saw-tooth dip leg and anti-pulsation baffle to minimise pulsing. The water level is preferably maintained by a constant overflow weir, in combination with a suitable 'S' bend drainpipe. Filling rates will be sufficient to re-establish the seal within 5 minutes if the seal is broken. The seal vessel may be equipped with an internal steam coil / sparger for winterisation purposes as required.

Flare Gas Inlet

Manway

Water Inlet Level Inst. Level Inst. WL Level Inst. Water Overflow

Level Inst. Steam In Steam Out

Drain

DIA



3.3.2. Knock-Out Drum. Knock-Out Drums are designed to effectively remove hydrocarbon liquids from the main relief gas to prevent the possibility of carryover and "flaming rain" from the flare tip. The sizing of these vessels is generally based on the criteria defined in API RP 521 (Fourth Edition - March 1997) and considers residence time and drop out velocity of the liquid particles in the vapour flow. Since flare tips can handle small liquid droplets, the allowable vertical velocity in the drum may be based on that necessary to separate droplets from 300 microns to 600 microns in diameter (typically 450 microns). Knock-Out Drums will be designed to avoid the accumulation of hydrocarbon liquid and will be equipped with instrumentation and control to monitor liquid level and pump out facilities.

Flare Gas Outlet

Flare Gas Inlet

Manway Pressure Gauge Conn.

Temperature Inst.

Level Inst. Level Inst. LL Level Inst. Level Inst.

Drain

DIA



3.4. FLARE PILOT AND IGNITION SYSTEMS. One of the main considerations for flare ignition is reliability of operation. An ignition system must be capable of fast performance and repeatability of use over and over again, under all environmental and operating conditions. GBA flare pilots and ignition systems are used throughout the world from the extreme cold of the Alaskan North Slopes to the intense heat of the Saudi Arabian desert and have experienced the arduous duties of the North Sea on oil and gas production platforms. Ignition Panels A complete range of ignition panels is available from GBA, designed for manual or automatic operation or a combination of both. These systems will ignite the GBA flare tip pilots from remote locations either through: 1) conventional Flame Front Ignition techniques or 2) High Energy ignition. GBA Pilots GBA standard G-100 pilots are offered on all types of GBA flare tips. The number and position of the pilots depends on the flare type and diameter. The pilot ignitor nozzles have been developed over many years of operational experience and offer maximum reliability of ignition and stability in winds in excess of 120mph (200 km/hr). The pilot ignitor nozzle and venturi mixing assembly is fabricated from alloy steels to ensure a long service life. For cases where pilot fuel gas has a high sour content, specialised alloys are used. GBA pilots are used in combination with all GBA ignition systems.



3.4.1. Flame Front Generator. The basic GBA ignition panel is the Flame Front Generator (FFG). Flare pilots can be serviced through either individual flame front lines or via a splitter manifold located on the flare tip. Fuel gas and instrument air are supplied to the ignition chamber in the correct quantities via an on / off valve, needle valve and restriction orifice. The mixture is then ignited using an electric spark. The resulting flame front will travel down ignition line(s) to light each pilot either separately or through a splitter manifold. This flame front may be transmitted for distances of up to 1,000 metres along standard small bore pipework. The panel will continuously monitor the pilot burner flames via the installed thermocouples and should a failure be detected a visual alarm will be raised in the FFG and at the same time an alarm will be activated in the control room via remote contacts. The Flame Front Generator (FFG) is of free standing easel type construction fabricated from carbon steel. The framework will be open to atmosphere onto which is mounted the instrument and electrical enclosures certified for the specified area classification and weatherproof to IP65 (minimum). The panel will provide the functions of pilot ignition and monitoring of pilot status via thermocouples located in the pilot nozzle heads. HS Spark

PG Air in

Spark Plug Flame Front Outlet

¾"

Ignition Chamber PG Gas in

½"

The FFG is offered as a standard proprietary item of equipment and can be supplied for either manual or automatic operation or a combination of both. Pilot fuel gas and purge supply can be accommodated as a modification to the system if required.



3.4.2. Natural Draft Flame Front Generator. In situations where compressed air is not available, the Natural Draft Flame Front Generator can be used. The principle of the Natural Draft FFG is straightforward. Fuel gas at moderate pressure is ejected through a small drilling forming the jet of a venturi inspirator. The action of the gas jet passing through the throat of the venturi causes a local drop in static pressure, which causes air to be drawn into the venturi intakes and mixed with the gas. The resulting gas/air mixture passes through an ignition chamber and via a length of 2" / 3" piping to the flame front connection of the flare pilot. In this way a continuous length of piping is filled with a flammable mixture which, when sparked in the ignition chamber will ignite and send a flame front through the 2" / 3" line to light the pilot. This is similar to a conventional FFG, which uses compressed air in lieu of an inspirator to achieve the same result. The other main advantage that the Natural Draft FFG has over the compressed air type is in its ease of use and its wide tolerance of set pressures. The Natural Draft HS HS FFG is normally set up to operate at a Spark certain fuel gas Open SOV Ignite pressure say, 25 psig. Experience has shown that typically the unit will still function correctly over about PG a 16 psi range thus, 2" or 3" SOV providing you set Fuel Flame the gas pressure Spark Gas Front Plug within the range 17In Outlet 33 psig, the system will work reliably! FILTER In addition, it is extremely IGNITION INSPIRATOR CHAMBER repeatable, when set VENTURI up in the above manner it will work first time every time! This certainly is not true of the compressed air type where air and gas pressure are critical to within a few psi and repeatability is difficult to achieve. GBA has the knowledge to design Natural Draft systems of up to 170m pipe run incorporating bends, fittings and splitter manifolds. The Natural Draft FFG is of freestanding easel type construction, fabricated from carbon steel. The framework will be open to atmosphere onto which is mounted the instrument and electrical enclosures certified for the specified area classification and weatherproof to IP65 (minimum). Flare pilots can be serviced through either individual flame front lines or via a splitter manifold located on the flare tip. The Natural Draft FFG is offered as a standard proprietary item of equipment and can be supplied for either manual or automatic operations, or a combination of both. Pilot fuel gas and purge supply can be accommodated as a modification to the system if required.



3.4.3. CHT High Energy Electric Ignition Pilot The GBA CHT pilot is a direct electric ignition flare pilot that eliminates the need for conventional flame front generation systems. Using this system the pilot flame is directly lit by a High Energy spark generated adjacent to the pilot nozzle. The term "High Energy" is used to denote ignition equipment which feature sparks formed by the rapid discharge of large capacitors at relatively low voltage across the semiconducting layer of a surface discharge spark plug. The spark produced is so powerful that no accumulation of moisture, dirt or oil can prevent ignition occurring. This makes the High Energy system particularly suited to flare pilots where exposure to contamination is always likely. The spark plug forms the upper part of an ignitor rod, which is located within the pilot mixture tube and extends from the pilot nozzle to a point near to the Pilot flare tip base flange. At this point a connection is made Nozzle with an ultra high temperature cable (rated at 600°C) which is run down the flare stack to a point where the thermal radiation has reduced to an acceptable level. This distance is typically 10m. At this point a shielded junction box is used to connect with a suitable multi-core Spark Plug cable which is the used to run down the flare stack and to the control panel. Within the control panel is mounted an advanced Thyristor switched high energy pulse ignitor unit designed to provide a rapid series of powerful sparks at the ignitor head. A key advantage of this technology is that the interconnecting cable can be virtually any length enabling the control panel to be located outside the flare sterile area at any convenient location. Ignitor Rod The voltage used for the spark is limited to 2.5 kV. This is substantially less than high tension ignition systems and is markedly less liable to tracking / shorting out. The ignitor unit can be powered from any available mains AC supply or even from low voltage DC supplies. Either standard or Explosion proof versions are available. Pilot flame monitoring is achieved using thermocouples mounted in the pilot nozzles. The thermocouple is run within small bore conduit and is therefore supported over its entire length. This simple technique has greatly extended thermocouple service life by preventing failures due to mechanical fatigue caused by vortex shedding in windy conditions. The thermocouple signals are run back to the control panel where temperature switches are used to determine the pilot status. This is displayed via red and green lamps on the panel front and volt free contacts are provided for client use. Using the CHT system it is very straightforward to incorporate automatic re-ignition upon detection of a pilot flame-out.


High Temperature Cable

Inspirator Assembly

Pilot Gas Inlet


3.4.4. DESI Direct Electric Spark Ignition. The GBA DESI system is a direct electric ignition flare that eliminates the need for conventional flare pilot. Using this system the main flare flame is directly lit by a High Energy spark generated in a special pilot ignition chamber nozzle which is fed with a small bleed of flare gas from the main tip. Flame Retention Within the ignition chamber the flare gas flow Lugs is mixed with air and then ignited continuously by the HE spark thus producing a pilot flame Ignition Chamber which ignites the main flame. The term "High Energy" is used to denote ignition equipment which feature sparks formed by the rapid discharge of large capacitors at relatively low voltage across the semi-conducting layer of a surface discharge spark plug. The spark produced is so powerful that no accumulation of moisture, dirt or oil can prevent ignition occurring. This makes the High Energy system particularly suited to situation where exposure to contamination is always likely.

HE Ignitor Rod

High Temperature Cable

Wind Shield

Air Lock Seal

The spark plug forms the upper part of an ignitor rod, which extends from the ignition chamber to a point near to the flare tip base flange. At this point a connection is made with an ultra high temperature cable (rated at 600°C) which is run down the flare stack to a point where the thermal radiation has reduced Flaring to an acceptable level. This distance is Gas Inlet typically 10m. At this point a shielded junction box is used to connect with a suitable multi-core cable which is then used to run down the flare stack and to the control panel. Within the control panel is mounted an advanced Thyristor switched high energy pulse ignitor unit designed to provide a rapid series of powerful sparks at the ignitor head. A key advantage of this technology is that the interconnecting cable can be virtually any length enabling the control panel to be located outside the flare sterile area at any convenient location. The voltage used for the spark is limited to 2.5 kV. This is substantially less than high tension ignition systems and is markedly less liable to tracking / shorting out. The ignitor unit can be powered from any available mains AC supply or even from low voltage DC supplies. Either standard or Explosion proof versions are available.



3.5. STEAM CONTROL AND MONITORING SYSTEMS. For the majority of refinery and petrochemical applications, the operator requires that the combustion of the relief gas should be clean and smokeless under certain operating conditions. As previously discussed, this is achieved by adding a suppressant such as steam, into the emergent flame through the flare tip causing increased mixing of the air with the gasses and altering the chemistry of burning. A control system is often required to proportion the steam flow into the flare to provide clean combustion, economically and without wastage. Historically, flow meters were used to try and achieve a level of control, but with little success for the following reasons: variation in relief gas composition requires different quantities of steam injection; required to operate over significantly wide range of flows; as the meter is located "in-line" it caused an obstruction to flow. Flow Controller (by client) FIC

I

Steam Supply

Infra-Red Remote Sensor P

To Flare

6" 4"

1" Minimum Flow By-Pass

However, more recently, the market has seen the development of a monitor, which contains a unique infra-red optical unit. This detects flame density changes in the hydrocarbon flames and provides the process variable signal for steam control allowing only the correct amount of steam necessary for the required smokeless capacity. The optical monitor and associated controller is field mounted and is unaffected by fog, rain or low cloud.



3.6. STRUCTURES. For most elevated flare systems, the greatest cost item is the support structure. GBA is the world's leading company in the design and fabrication of flare structures and has considerable experience in supplying systems for all environmental and operational conditions. We pride ourselves in optimising the structural requirements by careful consideration of all relevant factors, ultimately providing an economic final solution. Several criteria need to be considered in order to determine the support mechanism: flare relief rates and duration thermal radiation smoke emissions and pollutants noise location of other plant and proximity to the flare personnel access regulations GBA are able to offer any type of flare structure (refer below) and are in a unique position to provide the structural and mechanical design, fabrication, trial assembly and erection using "inhouse" resources. Designs are undertaken to all commonly used European and American codes, employing advanced finite element and dynamic simulation techniques. Structures: guyed; free standing derrick; guyed derrick; demountable riser derrick; self support; offshore towers and booms; flare tip removal equipment.



3.6.1. Guy Wire Supported Stacks The lightest and lowest cost support option is the guyed flare, used when space and plant layout is sufficiently large to accommodate the requirements of the dead men.. Careful consideration, however, needs to be given to this design when extremes of process temperature could produce significant expansion of the riser under certain conditions. Guy wires would therefore need to be set relatively slack, which under high wind conditions results in a system, which is less able to resist the wind forces and will deflect more. Under these conditions, an alternative, and widely used method of supporting the flare, whilst still utilising guy wires, would be to locate the flare riser(s) within a lightweight tower so that the flare riser(s) is free to move. The tower (and not the main riser) would be supported by guy wires at various elevations.

EL 150.0m

Flare Tip

EL 146.0m Top Platform

120°

120°

Steam Lines

Ladder (Typ.) 120°

Guy Wires Rest Platform

Water Seal Drum Guy Deadmen 60" 150#

EL 0.0m 80.0m



3.6.2. Derrick Supported Stacks. The Derrick support structure is used for very tall systems, which preclude the use of guy wires, in areas where space is at a premium due to the proximity of plant and personnel, or where several flare systems require to be positioned together.

EL 80.0m

EL 76.0m

Derricks will be designed and fabricated from tubular carbon steel sections with main support members supplied in 12m flanged lengths. Cross bracing and secondary members will be tubular, with end connections formed from splice pates fitted into slotted tube ends. These are bolted to matching plates welded to the legs. Using this technique, both main support members and cross bracing can be readily hot dip galvanised ensuring complete corrosion protection. All derrick and riser components will be hard stamped with individual number cross referred to the fabrication drawings and erection procedure. The derrick will be trial assembled in our works. The derrick structures are designed as bolted or welded or a combination of both.

Flare Gas Inlet EL 0.0m

11.0m square



3.6.3. GBA Demountable Flare GBA Demountable flares have a number of unique features that offer the operator distinct advantages over conventional (fixed) flare stacks. These are principally: if duty / standby flare stacks are used all flare tip maintenance can be done from grade without taking the flare system off-line; a structure can be designed to accommodate future extra flare risers, which can then be installed at a later date without requiring a plant shutdown; multiple risers can easily be accommodated in a single structure; riser installation is simplified reducing craneage costs. In a demountable system the flare gas risers are constructed in flanged sections, usually 20-25m long. These are all equipped with guide rollers which retain the riser within a central box of guide rails that forms the inner part of the derrick structure. This arrangement allows the riser sections to be free to move vertically within the structure. The riser sections are complete with all their necessary service lines and cables, as these must be mounted and demounted along with the riser. If steam lines are installed then expansion bellows are needed on each section. At the base of the riser stack there is a hinged base plate, which permits the risers to be raised from the horizontal into the vertical. The sequence of installation is firstly to locate the upper section of riser (including the tip) horizontally on the hinged base and raise it to the vertical position using the dedicated canting winch (refer to the following summary). The first section is then attached to the lifting blocks and is raised by the two main winches to a height sufficient to allow the second section to be installed below it. The GBA system allows a straight vertical lift with virtually no friction component. This means that very large riser diameters and heights in excess of 200m present no problems. The two main winches are electro-hydraulic units. These give the fine control necessary for the exact positioning of the risers. The two winches are linked together and controlled from a single point. The second section is installed by canting it into position beneath the first. The two flanged sections are then bolted together, including all the service lines. They are then lifted, as one piece, to make way for the third section to be positioned underneath. In this way all the riser sections are sequentially installed until the flare tip is in its operating location and the lower section, complete with the gas inlet, is in place ready for connection to the flare header. Personnel access is generally limited to the first working platform at 25m although some work is required at the rigging platform at elevation 50m. Radiation shields are installed at these locations for personnel protection. Access to the principle working platforms is by a stairway, while access to the tower upper levels is by ladders.



SUMMARY

Riser Installation Procedure 1)The top riser section (i.e. the section that includes the tip) is bolted to the hinged base plate. The canting winch is rigged up and its rope is attached to the lifting lug on the riser. This winch is used to raise the riser section into the vertical.



2)The riser section is held vertical while the main lifting wires are attached to the lifting lugs. The main lifting winches are used to lift the riser section vertically, up the structure, within the guide rails. In plan view the guide rails form a box around the riser. The riser is retained centrally within this box by a series of rollers, which loosely engage with the rails as the section is lifted.



3)Riser Section 1 is held by the main winches at a sufficient elevation so as to allow Section 2 to be installed beneath it. Section 2 is attached to the pivot table and, as before, the canting winch is used to rotate this section into the vertical directly below section 1. Section 1 is then lowered to allow the two sections to be joined by installing the flange bolts and gaskets. Service piping is also connected at this stage.



4)Once the two sections are connected the lift wires can be transferred to the lugs on Section 2. The two sections can then be lifted together to allow Section 3 to be installed beneath them. In this way all the subsequent sections can be installed until the flare tip reaches the top of the structure and is in its operating position. Dismounting the risers is the exact reverse of this procedure.



3.7. TYPICAL P&ID’S.


ME-801 Flare Stack

SET POINT

FI

TE

TE

TE

PF-20/12 Flare Tip

FIC

TAL 002

TAL 001

TAL 100

Pilot 2 Fail

Pilot 1 Fail

TAL 003

HS 001

FI I

Common Pilot Fail

P FE

FIT

3" Assist Gas

1"

2" 12" Riser

FE

2" Water

Pilot 3 Fail

Ignition Spark

1" 1"

1" PCV

12"

PG Air in 1" 150#

¾"

PG ¾" PCV 2"

¾"

1"

PG ¾"

V-802 Knock-Out Drum

12" Acid Gas

Gas in 1" 150#

½" PAL

¾"

PAL PCV

LSHH PSL

LSH

PG Gas in 1" 150#

LG LG

LT

LSL LIC

2" Steam Out

¾"

2" Steam Out 2" Cooling Water

I

2"

2"

P

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

0

Initial Issue

20/05/98

PCAW

.

REV

DESCRIPTION

DATE

BY:

CHKD:

3" To Pumps LI

2"

3"

LAL

Water Seal Drum I Pump Start Pump Selector Switch

I

¾"

Pump Stop

HS

REVISIONS

LAHH

GBA Flare Systems

To MCC Pump A

To MCC Pump B

4 Kingfisher Court Farnham Rd SLOUGH SL2 1JF England Tel. +44-(0)1753-575710 Fax.+44-(0)1753-575750

Project No.

Client

E0679

OEIC for NIOC .

Drawing No.

101

Title

Abadan Refinery Acid Gas Flare P & ID

Drawn by

PCAW Scale

© GBA Ltd. This drawing must not be reproduced or disclosed without prior permission.

None

Cable C-3TA-5302B-TC

A3-5301 Ammonia & Syngas Flare Package

Cable C-3TA-5302D-TC

Cable C-3TA-5302C-TC

Cable C-3TA-5301B-TC

Cable C-3TA-5301A-TC

Cable C-3TA-5301C-TC

Cable C-3TA-5302A-TC

JB

A3-5302 Ammonia Flare

TA 5302A

TA 5302B TC

TA 5302C TC

A3-5301 Syngas Flare

TA 5302D TC

TA 5301A

TA 5301B TC

353-JT-502

TC

TA 5301C TC

TC

PF-42/24 Flare Tip

by client

353-T-502 cable

JB 353-JT-501

PF-30 Flare Tip

TA 5301B

TA 5301A

L

TA 5302B

TA 5302

L

Pilot 1 Fail

by client

TA 5302A

353-T-501 cable

L

TA 5301

L

L

Pilot 2 Fail

Pilot 1 Fail

TA 5301C

HS 5303

Syngas Flare Common Pilot Fail

L

Ammonia Flare Common Pilot Fail

Pilot 2 Fail

1"

L

1"

L

TA 5302D

Pilot 3 Fail

L

1"

1"

1"

Pilot 3 Fail

30" Riser

24" Riser

1" 1"

Pilot 4 Fail

1"

1"

1"

1"

Ignition Spark

To Ammonia Flare

TA 5302C

1"

1"

1"

PCV 5304 PG 5301

¾" ¾"

¾"

From FFG Panel

Air in 1" 150#

¾"

¾"

¾" PG 5302

¾"

¾" ½"

Gas in 1" 150#

Pilot Gas from FFG

24" 150# Ammonia Gas

36" 150# Syngas

LICA 5302

LICA 5301 1"

TX TX 2"

2"

1"

2" Element Over-Temp Protection

2"

LG 5304

1" Pilot Gas to Ammonia Flare

LG 5303

HH TA 5304

TA 5304

H TX LICA 5301

2"

2"

L

EHR

2"

2"

Local Control Box

To LCV Electric Heater E3-5301

¾"

¾"

H 2"

2"

LICA 5302 L

Knock Out Drum

Notes

1. All instrument tag numbers are prefixed by "3"

0

03/12/98

Issue EM.

Date DATA

ISSUE FOR APPROVAL

SCALA - Scale

. DESCRIZIONE - Description

.

Dwg. DIS.

COMM. - Job

CLIENTE - Customer

.

GBA

.

Ckd App'd Controll APPROV

.

. DIS. - Dwg.

. TITOLO - Title

.

DIS. - Dwg.

.

ENGINEERING AND CONSTRUCTION

.

Via A. Ramazzotti, 24 20052 MONZA (MI)-ITALY Tel. (039) 49.27.18 NOME DISEGNO:

. UNITA' DI MISURA:MM

INDICE MODIFICA - Rev. Index

1

2

3

4

5

6

7

8

9

10

SCALA DI PLOTTAGGIO: 1=15

G.B.A.

Knock Out Drum

FL-2301 Flare Stack TE

TE

TE

FIC

GCT-16C Flare Tip

I

P

6" Steam

TAL 002

TAL 001

Pilot 2 Fail

Pilot 1 Fail

TAL 003

HS 001

TAL 100 Common Pilot Fail

6" Steam Riser 1"

4" 16" Riser

1"

1"

1"

Pilot 3 Fail

Ignition Spark

1" 1" PCV PG Air in 1" 150#

¾" ¾" PCV ¾" PG ¾" PAL

¾"

20" Flare Gas I

Gas in 1" 150#

½" PAL

PCV

P

2" Water

PSL

PG

1" PCV LG

LT

LIC 2"

2"

LI

3"

LAL

Water Seal Drum

¾"

RO

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

0

Initial Issue

02/11/98

PCAW

.

REV

DESCRIPTION

DATE

BY:

CHKD:

REVISIONS

GBA Flare Systems 4 Kingfisher Court Farnham Rd SLOUGH SL2 1JF England Tel. +44-(0)1753-575710 Fax.+44-(0)1753-575750

Project No.

Client

E0698

FWF for AMOC .

Drawing No.

101

Title

Lube Oil Expansion Flare Package P & ID

Drawn by

PCAW Scale


None

TE

Pilot 1 ON XA

TAH

Common Pilot Fail

Pilot 1 OFF

CSF-1-20 Flare Tip

TAH

Pilot 2 ON

TAL

TE

Pilot 3 ON

TAL

TAL

Pilot 2 OFF

Pilot 3 OFF

HS

HS

HS

Auto/Man Select

Auto/Man Select

Auto/Man Select

HS

HS

HS

Ignite Pilot 1

Ignite Pilot 2

Ignite Pilot 3

Ignitor Cabling

1"

1"

24" Riser

TAH

TE

1E-230-FC01 Flare Stack

1"

PCV BESP

GBA

GBA

BESP

BESP

GBA

PI

Fuel Gas 1" 150# RF

½"

1" BESP

GBA

24" 150# Flare Gas

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

0

Initial Issue

30/9/98

PCAW

.

REV

DESCRIPTION

DATE

BY:

CHKD:

REVISIONS

GBA Flare Systems 4 Kingfisher Court Farnham Rd SLOUGH SL2 1JF England Tel. +44-(0)1753-575710 Fax.+44-(0)1753-575750

Project No.

Client

148

Bechtel Snamprogetti Joint Venture

Drawing No.

148/101

Title Karachaganak Development Project - Phase II Flare System P & ID

Drawn by

PCAW Scale


None


FLARE RADIATION CALCULATIONS AND TECHNIQUES.



4. FLARE RADIATION CALCULATIONS AND TECHNIQUES. 4.1. RADIATION ISOPLETHS. GBA Engineering and Construction use FLARESIM to calculate thermal radiation levels from flares. This software is commercially available and is used extensively throughout the industry to assist engineers in the design and evaluation of flare systems with regards to thermal radiation and noise characteristics. FLARESIM has the following important capabilities: It is applicable to the design of refinery, chemical and gas plants in addition to offshore oil and gas production platforms. Correlations are available for modelling sonic, steam and air assisted flares, in addition to traditional pipe flares. A generic emissivity correlation has been incorporated within the programme to predict emissivity of a wide range of hydrocarbon fluids with different types of flare tip. Liquid flaring systems may be handled. Wide range of applications for the calculation of thermal radiation is available. These include an integrated multi-point method in addition to both the Hajek / Ludwig and Brzustowski / Sommer method, which are presented within the API guidelines for flare system design. Full three dimensional flare shape analysis with complete flexibility in specification of the geographic location and orientation of all stacks, wind speed and receptors. A wide range of calculation types are available for: specific points points on a grid stack / boom sizing isopleths contours for sterile area definition The full evaluation of multiple flare stacks. This enables the analysis to include radiation from adjoining plant flare systems. For more information please visit http://www.softbits.co.uk/ Typical radiation isopleths are included herein for a range of applications to include: offshore production platforms onshore single-point flare systems onshore multi-point flare systems horizontal burn-pit systems. In addition, we include a copy of a flare radiation report survey undertaken for a major operating company, as part of a contract to supply 120m elevated smokeless flares at a site in the UK, which explains the basis of calculations and parameters considered in the assessment of thermal radiation from the flare.



4.2. THERMAL RADIATION PLOT. 1. Introduction. This document defines the predicted thermal radiation emission from the elevated HFL and LFL flare stacks, items 41-S-700 and 41-S-701. 2. Basis of Calculation. The plots have been produced using FLARESIM Ver 2.39. This is a commercially available program produced by Softbits Limited. This software produces a graphical output defining the predicted radiation of any given flare system. The principal user inputs are defined on the plot output. Several calculation methods are available for use. In this case the method employed is that given in API RP 521. 3. Explanation of Plots. The plots produced represent a vertical plane through the flare stack (the thick black line shown on the lower right of the plot) in the downwind direction. The predicted flame shapes are shown as single black lines coming from the top of the flare stack. Thermal radiation is represented by lines of equal intensity (isopleths). These are shown for a variety of levels. The stack height in this case is 120m, which is made up of a 117m high stack and 3m long tip. Ground level is at EL. 0.0 4. Process Details. Plot A is presented for simultaneous emergency relief conditions for both the HFL and LFL flare systems. Plot B is for the future case when the HFL flow rate is increased to 360 t/h. The wind speed is 14 m/sec and an allowance for solar radiation of 440 W/m2 is included. The F-factor used is 0.31 for both flares as specified. No atmospheric absorption of radiation due to humidity is applied. 5. Interpretation of Results. The principal criteria in this case is for the radiation to be less than 3.2 kW/m2 at the edge of the sterile radius which is 120m. Plot A shows that the 3.2 kW/m2 contour intersects the ground at a distance of 93m from the stack. Thus this requirement is satisfied. Plot B is given for information only.



4.3. SINGLE AND MULTI TIP ONSHORE INSTALLATIONS.



4.4. OFFSHORE INSTALLATIONS.


RADTEMP

GBA Steelwork Temperature Analysis

Project Job Number Ambient Temperature Wind Speed Surface Absorptivity Surface Type Heat Loss

Ver 1.0 April 1998

: Khuff Gas TA Flare Tower

Date: By:

27/04/98 PCAW

Case

:

: 45°C

Flow

: 407000 Kg/h

: 2.00 m/s

M.W.

: 19.70

: E1033

: 0.70

Gas Temp

: 8°C

: t Tubular Incident Radiation : d Double Sided Heat Loss

Point

Radiation 2 (Btu/hr.ft )

Radiation 2 (KW/m )

Temperature (°C)

Shielding (%)

EL.39.0

17,704

55.85

280.6

30.00

EL.36.0

12,288

38.76

232.6

25.00

EL.33.0

9,286

29.29

202.4

20.00

EL.30.0

7,411

23.38

182.0

15.00

EL.27.0

6,139

19.37

167.4

10.00

EL.24.0

5,226

16.49

156.4

5.00


4.5. HORIZONTAL BURNPIT INSTALLATIONS.



COMPANY PROFILE.



5. COMPANY PROFILE. 5.1. GENERAL. GBA Engineering and Construction employs over 40 personnel at its offices in London, Milan and Houston, comprising process, mechanical, structural and instrument engineers, CAD draughtsmen and designer draughtsmen, QA/QC Managers, inspection and support staff in addition to qualified welders, fitters, construction crew and supervisors based at our fabrication plant in Parma. GBA Engineering and Construction employs qualified, professional engineers as follows:

Process Engineering Structural/Mechanical Engineering Design Draughtsmen Project Management QA/QC Inspectors

4 4 5 4 2 1

5.2. EXPERIENCE PROFILE OF KEY ENGINEERING STAFF. Mr F.Magnavacca. MSc qualified engineer. Has worked extensively in the civil, construction and oil and gas industries both in the UK and Italy. Whilst in the UK, during the mid 80's, Mr Magnavacca was employed as a consultant for Michael Barclay Partnership Consultant Engineers. He has extensive experience in the mechanical and structural design of Flare Systems since joining the company as a partner in 1985 and has been engaged in engineering, fabrication and the construction of process plants for the oil, gas, refining, petrochemical and other industries. Responsible for overall project execution including: review of client specifications, mechanical design, equipment specifications, procurement, shop fabrication and field construction activities, scheduling and cost control, client relations and commissioning activities. Mr Magnavacca is a chartered member of the Italian Institute of Engineering. Mr P.Favaro. MSc qualified engineer. Has worked extensively in the civil construction and oil and gas industries and is responsible for the detailed design, engineering and drafting department within GBA. Prior to joining GBA as a partner in 1985, Mr Favaro worked for the Montedison Group, responsible for sitework and construction. Mr D.English. BSc Chemical Engineering - Loughborough University (UK). Has over 18 years experience in the oil, gas, chemical and petrochemical industries, including process design of flare systems, hydrocarbon vapour recovery systems, submerged combustion LNG/LPG vaporisers, inert gas generators and incinerators, foreign contract negotiations, project management, start-up,



commissioning and trouble-shooting throughout the world. Experience has been gained whilst working for John Zink (9 years) and Kaldair Limited (9 years) before joining GBA Limited in 1997 as Managing Director. Worked for Howmar International during the early 1990's as Senior Process Engineer, responsible for the engineering and design of fuel gas treatment plants and oil contacting and separation plants. Mr English is a chartered member of the Institute of Chemical Engineers. Mr P.Watts BSc Chemical Engineering. Has worked previously for John Zink Limited (3 years) and Kaldair Limited (13 years) where he was Engineering General Manager responsible for the process, mechanical and structural design departments. Extensive experience, both onshore and offshore within the oil and gas industry, including process design, process research development, system designs for all types of flares, LNG/LPG vaporisers, inert gas generators and incinerators in addition to commissioning and trouble shooting. Mr Watts had been directly involved in the development of new products during his employment with Kaldair including steam tips, ground flare burners, high pressure flare tips and hydrocarbon vapour recovery units. Mr Watts is a chartered member of the Institute of Chemical Engineering. Publications / Papers Numerous articles published for engineering services and presented by Mr Watts, including: - A Review of Onshore Flare Systems - Proven Solutions for Flaring in FPSO's (6th Annual Conference FPSO - Monaco) - Optimisation for Offshore Flare Structures - Advances in Flare Technology

1994 1991 1992 1994

Mr S.M.Swann B.Eng Mechanical - Sydney, Australia. He has previously worked for John Zinc (4 years) and Kaldair (13 years). A member of GBA Limited since 2001. Mr Swann has extensive experience in flare systems and nitrogen generation packages for all offshore and onshore oil, gas and petrochemical applications. Mr Swann holds UK offshore certification and has undertaken offshore flare inspection and commissioning. Mr D.Adcock Mr Adcock has been employed in the oil and gas industry since 1973. He has previously worked for Flaregas (4 years), Airoil-Flaregas Limited (14 years), Kaldair Limited (5 years) and has been with



GBA since 1999. He is named as inventor/joint inventor on 8 patents covering, radiant wall burners, steam injected flares, seals for flares, high pressure sonic flares and high pressure gas injection for smoke reduction on low pressure flares. Mr Adcock is registered with the Engineering Council as an Incorporated Engineer. Mr B.Bolanowski. BSc Engineering, University of Houston, Texas. Has over 12 years experience, including process design, contract negotiations, project management, start-up and trouble shooting of flare equipment throughout the world. 10/1996 - Present Snr Applications Engineer/ Vice President

GBA - Corona Inc

Responsible for all aspects of design and engineering of flaring equipment and systems. 8/95 - 10/96

Snr Applications Engineer

Birwelco Inc Houston, Texas

8/85 - 8/95

Snr Applications Engineer

Kaldair Inc Houston Texas



5.3. FABRICATION SHOP CAPABILITIES. Fabrication of equipment, QA/QC activities and inspection is undertaken at our manufacturing plant located at Castelguelfo, Parma, Italy covering 15,500 m2. It is almost completely dedicated to the production of flare systems including risers, vessels and structures, and has a segregated stainless steel shop dedicated to the fabrication of flare tips and stainless steel components. The factory is 3km from the centre of Parma and has sufficient area to enable the trial assembly and fit-up of very large derrick structures. Being close to the A1 and A15 Motorways there is excellent access via the major road networks to Italian ports such as:Adriatic Sea: Marghera Chioggia Ravenna

Tyrrhenian Sea: Genova La Spezia Livorno Carrara

5.3.1. Fabrication Plant Address. GBA Costruzioni srl Via Emilia 39 43010 Castelguelfo Parma Italy Tel: Fax:

00 39 521 619249 00 39 521 619439

5.3.2. Available area. 4,500 m2 11,000 m2

Covered: Outdoor:

5.3.3. Workforce. Number

Description Administration Technical/Engineering QA/QC

1 3 1

Production: Foremen Inspectors Pipe Fitters Drillers/Cutters Qualified Welders Mechanical Erectors Semi-Skilled

5 1 2 4 6 2 4



5.3.4. Tools and Plant. Equipment Overhead crane Mobile crane Fork lift truck Fork lift truck

Capacity 6 tonne 7.5 tonne 1.2 tonne 2 tonne

Quantity 4 2 1 1

TIG TIG MIG/MAG MIG/MAG SMAW TAC Welding

400A 300A 500A 400A 400A 300A

Plasma

40kVA

5

Cutter Cutter Cutter Profiling cutter Drilling machine Compressed air plant

508 mm dia 273 mm dia 219 mm dia ang. 150 x 13 various diameters 8 barg – 3000 l

1 1 1 2 5 1

2 2 6 2 4 12

5.3.5. General. The fabrication shop is wholly owned by the GBA Group of Companies and, with current resources, has a maximum annual production capacity of 2,000 tonnes. As stated above, the total works area is 15,500m2 of which 4,500m2 is under cover including: Structural Workshop Process Equipment Workshop Stainless Steel Workshop Store

2,500m2 1,200m2 200m2 600m2

The remaining 11,000m2 utilised for outside storage, R & D and trial assembly of large structures and systems. Maximum width/height of shop: 40m x 50m x 7m Shop access is from a main road through 7m wide gates.

5.3.6. Welding. All welders are qualified to ASME IX All procedures are qualified to ASME IX Weld procedures and welder qualifications are generally performed under the surveillance of Bureau Veritas.


GBA ENGINEERING & CONSTRUCTION LTD

Supplier Number:

10043321

Date of Registration: 9th February 2001 Company Name:

GBA ENGINEERING & CONSTRUCTION LTD

Address:

4 KINGFISHER COURT, FARNHAM ROAD SLOUGH BERKSHIRE SL2 1JF UNITED KINGDOM

Telephone:

+44 (0)1753 575710

Fax:

+44 (0)1753 575750

Email:

[email protected]

Web:

http://www.gba-flares.com


5.4. SUB-SUPPLIERS. 5.4.1. Fabrication. All fabrication and assembly work for equipment supplied by GBA is performed by our manufacturing facility GBA Costruzioni srl, Parma, Italy. The following is a general listing of items or materials which are purchased from other suppliers. Mills

Pipework for flare risers and service lines. Plate and pipework for flare tips Fasteners (nuts/bolts) etc.

Stockists

Pipework for derrick structure members Profiles for ladders and platforms.

Regular sources for the supply of plate and pipework forgings: Plate Pipe

CRSI / Ferrometalli (Italy) TAD/TAL/Marcagaglia/ORSI (Italy) Eisenbau Kramer (Germany) Special Forgings/SCOM (Italy) Microfound (Italy)

Forgings Castings

5.4.2. Electrical / Ignition Panels. GBA Engineering and Construction would consider the following sub-suppliers for ignition systems and panels:

Smitsvonk Holland BV - Zoetermeer, The Netherlands. Suppliers of electric and electronic low voltage ignition systems for use in: petrochemical / chemical industries (onshore and offshore) industrial furnaces and boilers elevated and ground flares incinerators Smitsvonk has supplied flare ignition systems to the following companies:

Main end-users AKZO Nobel DSM Bura-Leuna Exxon Gas Unie Dow Benelux (Terneuzen) NAM Hoogovens

Dutch Chemical Company Dutch Petrochemical Company German Chemical Company

Dutch Oil and Gas Company Dutch Steelwork



Pertamena Shell

Indonesian Oil Company Australia / UK / Germany / Malaysia / Netherlands / New Zealand / Norway / Denmark / Sweden / South Africa / Singapore

Flare Companies Airoil Flaregas Callidus Itas John Zink Kaldair

Prematechnic Escher GBA Rohr und Tankbau

Combustion and Energy SRL – Italy. Combustion and Energy SRL are specialists in the supply of the following systems for petrochemical and chemical industries: Flare pilot burner ignition systems Flame detection systems Aircraft warning light systems (AWL) Burner Management Systems (BMS) Shutdown Systems (SDS) Distributed Control Systems (DCS)

Unitech Engineering – England. Unitech Engineering Services Limited offer the following services: Instrument / electrical engineering and design of equipment and control systems. In-house manufacture of control and analyser systems. Installation of instrument and electrical equipment at customer site. Testing of completed installations. Area of expertise: Oil and Gas industry, including equipment for hazardous areas. Bulk nitrogen and oxygen supply industry. Filtration equipment for the water and chemical industry. Customer List: Air Products PLC ESSO Petroleum Lube Oil Consoles PCI Membrane Systems

Howmar International Eliot Turbomachinery Jordan Kent Metering Systems Major Flare Suppliers

While working for these customers Unitech have gained a wide range of experience working on projects for companies such as BP, Shell, Amoco, Statoil, Foster Wheeler and many others.



LIST OF INDUSTRIAL CODES AND STANDARDS USED BY GBA.



6. LIST OF INDUSTRIAL CODES AND STANDARDS USED BY GBA. GBA's engineering department is fully familiar with most international oil and gas standards and codes, and has worked extensively to standards and codes imposed by the oil and gas majors and operators, multi-nationals and contractors (refer to section 2 herein). Typical industrial codes and standards: International: ASME Sec VIII Div I and II AWS ANSI B16.5/B31.3/B46.1/A58.1 API RP 520 API 601/625 NEC-Art 500 BS 5500 ISPEL DIN CENELEC STOOMWEZEN ICAO / FAA EURONORMS SMACNA

ASME IX ASTM AISC/ASCE API RP 521 AFNOR A.D. MERKBLATTER BS 5950 TÜV TEMAR NFPA ISA NEC NACE

Oil Companies: Shell – DEP’s British Petroleum – Recommended Practices and Specifications for Engineering. Saudi Aramco Engineering Standard – SAES Saudi Aramco Material System Specifications – SAMSS Statoil Petronas Esso Mobil ADNOC ADCO ADMA OPCO Qatar General Petroleum Company (QGPC) Petroleum Development Company (PDO) Total Elf



MAIN CUSTOMER LIST.



7. MAIN CUSTOMER LIST.

ABB Lummus Global BV ADCO ADGAS ADMA OPCO ADNOC AGIP Al Furat Petroleum Al Jubail Petrochemical Co AMEC AMOCO ARAMCO ARCO Asprofos Engineering Axsia Howmar Bechtel Ltd Bharat Petroleum Borealis Antwerp Bouygues Offshore British Petroleum British Gas Brown and Root Caltex Chevron Oil Company Chiyoda Corporation Conoco Costain Daelim Corporation Daewoo Shipbuilding Damit Worley DOW Chemicals Elf Equate Petrochemicals Enagas Engineers India Ltd Esso/Exxon Eval Europe BV Fina Fluor Daniel Foster Wheeler Geoservices Grootint

Gulf Oil Hellenic Aspropyrgos Hindustan Petroleum Hyundai Engineering and Construction Ltd IHC Gusto Engineering Jacobs Engineering Jawaby Oil Services JGC Corporation John Brown Karachaganak Operating Company BV Kellogg/Brown and Root Kovoprojekta Brno Krupp Uhde Kuwait Oil Company Kvaerner Process Engineering Larmag Cheleken L G Engineering Linde Lukoil M W Kellogg Malaysian Shipyard Inc Mannesman Anlagenbau Mazagon Dock MHI Mitsui Mobil Mott Macdonald National Iranian Oil Company Nigeria LNG Company NPCC Oil and Gas Services Ltd OIECQ ONGC Parsons Passedena PDO PEMEX Petrobras Petrofac Petronas


Phillips Petroleum POSCO Prokop Brno Qatar Petrochemical Company Qatargas QGPC Ranhill Worley Raytheon R M Parsons Samsung Corporation Sarawak Shell Sembawang Singapore Refinery SADAF SARAS Saudi Arabian Petrochemical Company Single Buoy Moorings Shell Offshore Inc Shell Chemie SIPM Snamprogetti Sofregaz Stone and Webster Stork Engineers and Constructors BV Suedrohrbau Sunkyong Corporation Syrian Petroleum Corporation Tamoil Techint Technimont Technipetrol Technip Texaco Total Oil Company Toyo Engineering Universal Refining


INTERNATIONAL USERS REFERENCE LIST.



8. INTERNATIONAL USERS REFERENCE LIST. Please find attached a comprehensive reference list of complete integrated flare systems supplied by the GBA Group of Companies. This list clearly defines the scope of supply of equipment and services provided by GBA to major International Oil Companies and Contractors throughout the world for both onshore and offshore locations.


184637033 GBA Flare Systems

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