Page 89 - Oil and Gas Production Handbook An Introduction to Oil and Gas Production

discharged. One patented solution is a "ballistic ignition" system which fires
burning pellets into the flare gas flow.

6.5 Instrument air

A large volume of compressed air is required for the control of pneumatic
valves and actuators, tools and purging of cabinets. It is produced by
electrically driven screw compressors and further treated to be free of
particles, oil and water.

6.6 HVAC

The heat, ventilation and air conditioning system (HVAC) feeds conditioned
air to the equipment and accommodation rooms etc. Cooling and heating is
achieved by water-cooled or water/steam-heated heat exchangers. Heat
may also be taken from gas turbine exhaust. In tropic and sub-tropic areas,
cooling is achieved by compressor refrigeration units. In tropical areas, gas
turbine inlet air must be cooled to achieve sufficient efficiency and
performance. The HVAC system is usually delivered as one package, and
may also include air emissions cleaning. Some HVAC subsystems include:

• Cool: cooling medium, refrigeration system, freezing system
• Heat: heat medium system, hot oil system.

One function is to provide air to equipment rooms that are secured by
positive pressure. This prevents potential influx of explosive gases in case of
a leak.

6.7 Water systems

6.7.1 Potable water

For smaller installations,
potable water can be
transported in by supply
vessels or tank trucks.

Photo: Lenntech Water
treatment & air purification
Holding B.V.

For larger facilities, it is
provided on site by
desalination of seawater

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