Oil and Gas Production Facilities Descriptions
Oil and gas production requires a number of facilities and components.
Drilling/development and production of oil and gas wells requires a number of facilities and components including the well pads, rigs, surface impoundments, access roads, pipelines, and pump stations or compressor stations.
The drill rig may be self-contained on a single truck for a shallow well or transported to the well site for assembly for deeper wells. Almost all drilling rigs and production wells have a vent and flare to release pressure. Storage areas would be established to house construction equipment, vehicles, pipe and pipe welding materials, and so forth.
If natural pressure is not adequate to force the oil, gas, or water to flow naturally, pumping equipment would be required. The power to operate these pumps would be supplied by gas or diesel engines or by electric motors.
Waste and Evaporation Pits
A number of surface impoundments, or pits, could be constructed during drilling and at the production stages, such as a mud pit (to collect used drilling mud and cuttings prior to disposal), a skimming pit (which reclaims residual oil removed with produced water), a sediment pit (stores solids that have settled out in storage tanks), or a percolation or evaporation pit (to dispose of produced water). Water removed from coal bed methane wells is often stored in unlined pits.
Tanks may be used for temporary storage of oil, natural gas liquids, and/or produced water. Tanker trucks (rather than pipelines) are often used to pick up oil produced in smaller, scattered fields.
Coal Bed Methane Facilities and Components
Coal bed methane wells require facilities and components similar to those for conventional oil and gas wells. However, where coal seams are shallow, smaller rigs (e.g., modified water-well drilling rigs) could be used rather than more expensive specialized oil and gas drilling rigs. The minimum threshold for a viable coal bed methane development has been estimated to be at least 400 wells or 200 billion cubic feet of production.
For coal bed methane projects, pipelines and compressors are normally only developed during the production phase (i.e., after it has been determined that the project would be economically viable). At conventional wells, a pump jack is initially used to pump water and sometimes oil, but not gas. It could be used at a conventional gas well in its later stage to remove increasing amounts of water. For coal bed methane wells, pump jacks are typically needed during the first few years to pump out water, but can be removed as the amount of water declines and mostly natural gas is produced.
Shale Gas Facilities and Components
Shale gas wells require facilities and components similar to those for conventional gas wells. Vertical wells can be used for gas development but increasingly, production strategies are relying on horizontal wells. In general, the economic viability of shale gas development is usually predicated on horizontal well drilling, hydraulic fracturing and the installation of multiple horizontal wells radiating out from a centralized drilling pad. Target drilling depths vary depending upon the nature of the shale gas formation.
Oil and Gas Treatment
Before oil and natural gas can be marketed, the fluids must go through a treatment process to remove water, dangerous gases, and other impurities. Some of the treatment can occur at the well site (fluid processing). After initial treatment, however, the crude oil or natural gas is sent through a pipeline to a centralized processing facility such as an oil battery or a gas plant. Gathering is the movement of oil or gas from a production well to the treatment facility.