Gas Processing Facilities

1. Inlet Gas — Rich gas from DPS & BBS
2. Inlet Separation — Rich gas arriving from DPS & BBS may still carry entrained liquids, condensate, and trace solids. The inlet separator is a vertical two-phase vessel that slows the stream down so gravity can pull these liquids and solids out, sending a clean gas stream onward to compression. Stable separation here protects every downstream unit from liquid carryover and fouling.
3. Inlet Gas Compressors — The inlet compressors raise the feed gas to the plant’s operating pressure, with interstage coolers and scrubbers knocking out the liquids that condense as the gas is compressed and cooled. A steady discharge pressure gives the treating units a constant, predictable feed.
4. Mercury Removal Unit — Trace mercury occurs naturally in many gas fields, and even a few micrograms per cubic metre will attack the brazed-aluminium heat exchangers of the cryogenic unit, as well as the aluminium trays and packing in the columns, causing amalgam corrosion and embrittlement. The gas flows through fixed beds of sulphur-impregnated adsorbent, where mercury is captured as stable mercuric sulphide. Placing the unit early in the train protects every exchanger and column downstream.
5. Gas Sweetening Unit — Hydrogen sulphide (H₂S) makes gas corrosive, toxic, and unsaleable if left untreated. The gas passes through fixed beds of solid adsorbent in a lead-lag configuration: the lead vessel removes the bulk of the H₂S, while the lag vessel safeguards downstream equipment and ensures the sweetened gas meets the sales gas specification of maximum 5 ppmv H₂S. Once a bed’s media is fully spent, it is replaced.
6. Gas Dehydration Unit — Any water vapour left in the sweetened gas would form ice and gas hydrates the moment temperatures drop in the cryogenic section, plugging exchangers and valves. The gas therefore passes through twin molecular-sieve adsorber beds: one dries the gas while the other regenerates. When a bed’s media becomes saturated, a portion of dry gas is heated and flowed from bottom to top to drive off the trapped water; toward the end of the cycle, the heater is bypassed so the bed cools back to operating temperature before switching back into service.
7. Cryogenic Unit — The heart of LPG and NGL recovery. Dry, sweet gas is cooled to roughly −110 °C through a chiller, exchangers, and a turbo-expander, which extracts work from the gas while dropping its temperature to maximise liquid recovery.
8. De-ethanizer Column — With the gas now chilled, it’s ready for its final split. The cooled gas enters the de-ethanizer, a packed column that separates methane and ethane (lean gas) overhead from the heavier C3+ liquid, which flows to the debutanizer for separation into LPG and NGL.
9. Export Gas Compressors — The lean residue gas leaving the cryogenic unit is at low pressure after expansion. The export compressors restore it to sales-pipeline pressure, with after-coolers bringing it back to specification temperature. A regulated slipstream is drawn off as fuel gas to supply the gas plant, power plant, DPS, and BBS, and the remainder passes through the Gas LACT unit for custody transfer metering into the sales-gas pipeline.
10. Debutanizer Column — The C3+ liquid stream from the de-ethanizer is a mix of propane, butane, and heavier gasoline-range liquids. The debutanizer is a distillation column that makes one clean cut: propane and butane vapours rise overhead, are condensed and become LPG, while the pentane-plus C5+ bottoms leave as a stabilised natural gas liquid (NGL) suitable for blending into crude oil.
11. LPG Storage Tanks — LPG is held as a liquid under its own vapour pressure in pressurised bullet tanks. Storage buffers the difference between steady production and batch offtake, and each tank carries relief, deluge, and gas-detection systems. Product is loaded onto road tankers for delivery to market, with each shipment weighed on a weighbridge to confirm the dispatched quantity.
12. NGL Storage Tanks — Stabilised pentane-plus liquids are held in low-pressure storage before export to DPS, where they are pumped into the crude-oil stream to enhance its API gravity, adding volume and value to the blend.

Products

• EXPORT GAS (To sales gas pipeline) — Lean, dry, sweet natural gas metered into the sales-gas pipeline.
• FUEL GAS (Powers plant & utilities) — A slipstream of treated gas that fuels the plant’s own turbines, heaters and utilities — the facility runs on the product it makes.
• LPG (To LPG road tankers) — Liquefied petroleum gas — a propane–butane mix — dispatched by road tanker.
• NGL (Blended with crude to enhance API) — Stabilised natural-gas liquids blended into the crude-oil export stream.

Utilities

Support systems — not part of the gas flow

• Flares — Safely combust relief and depressurised gas during upsets and maintenance.
• Drain Systems — Closed and open drain headers collect hydrocarbon liquids for safe recovery.
• Fire & Gas — Detectors and shutdown logic that protect the plant on fire or gas release.
• Instrument Air — Clean, dry compressed air that powers valves and instrumentation.
• Fuel Gas — Conditioned gas distributed to turbines, engines and heaters.
• Fire Water — Ring main, pumps and hydrants delivering firefighting water on demand.