Gas recovery apparatus, method and cycle having a three chamber evacuation phase for improved natural gas production and down-hole liquid management

A gas recovery apparatus for producing natural gas from a well and delivering the produced natural gas to a sales conduit, the well extending from the earth surface into a subterranean earth formation where the natural gas and liquid enter the well, the apparatus including tubing inserted into the well to create a casing chamber, a production chamber and a lift chamber which are separate from one another within the well, the gas recovery apparatus further comprising:

• a compressor having a suction manifold and a discharge manifold, the compressor creating a flow of relatively low pressure gas in the suction manifold and a flow of relatively high-pressure gas in the discharge manifold;
• control valves connecting each of the casing chamber, the production chamber and the lift chamber to the suction manifold and the discharge manifold to establish selective fluid communication between the suction manifold and each of the casing chamber, the production chamber and the lift chamber and to establish selective fluid communication between the discharge manifold and each of the casing chamber and the production chamber, the control valves also connecting the lift chamber and the discharge manifold to the sales conduit to establish selective fluid communication between the lift chamber and the discharge manifold and the sales conduit;
• a controller programed to supply control signals to the control valves to establish an opened state of each valve to permit fluid communication therethrough and to establish a closed state of each valve to prevent fluid communication therethrough;
• the controller delivering a sequence of control signals to the control valves to establish the opened and closed states of the control valves which establish fluid communication conditions through the casing chamber, the production chamber, the lift chamber and into the sales conduit during a multi-phase gas recovery cycle;
• the gas recovery cycle including a liquid capture phase during which pressurized gas supplied by the compressor moves liquid from the well into the production chamber, a liquid removal phase in which pressurized gas supplied by the compressor lifts liquid out of the well from the production casing through the lift chamber, a production phase during which natural gas is removed from the lift chamber and delivered to the sales conduit, and a three chamber evacuation phase executed by applying relatively low pressure within the casing chamber, production chamber and lift chamber after completion of the production phase and before execution of the liquid capture phase;
• and wherein:
• the controller establishes the states of the control valves during the liquid capture phase to establish fluid communication between the discharge manifold and the casing chamber and to establish fluid communication between the suction manifold and the production chamber and the lift chamber;
• the controller establishes the states of the control valves during the liquid removal phase to establish fluid communication between the discharge manifold and the production chamber and to establish fluid communication between the suction manifold and the casing chamber and the lift chamber;
• the controller establishes the states of the control valves during the production phase to establish fluid communication between the discharge manifold and the production chamber, to establish fluid communication between the suction manifold and the casing chamber, and to establish fluid communication between the lift chamber and the sales conduit;
• and
• the controller establishes the states of the control valves during the three chamber evacuation phase to establish fluid communication between the suction manifold and the casing chamber, the production chamber and the lift chamber.

A gas recovery apparatus for producing natural gas from a well in a multiple phase gas recovery cycle and delivering the produced natural gas to a sales conduit, the well extending from the earth surface to a subterranean earth formation from which the natural gas and liquid are produced at a bottom of the well, the gas recovery apparatus including a plurality of separate chambers extending between the well bottom and the earth surface, the gas recovery apparatus comprising:

• a compressor having a suction manifold and a discharge manifold, the compressor creating a relatively low pressure in the suction manifold and a relatively high pressure in the discharge manifold;
• control valves connected to the suction manifold, the discharge manifold and the plurality of chambers at the earth surface to selectively apply the relatively low pressure and the relatively high pressure to the plurality of chambers;
• a controller programmed to supply control signals to the control valves to establish an opened state of each valve to permit fluid communication therethrough and to establish a closed state of each valve to prevent fluid communication therethrough, and wherein:
• the controller establishes states of the control valves to establish fluid communication between the discharge manifold and at least one chamber at the earth surface to apply the relatively high pressure to the one chamber to lift liquid from the well bottom through another chamber to the earth surface in a liquid removal phase of the gas recovery cycle;
• and
• the controller establishes states of the control valves to establish fluid communication between the suction manifold and all of the plurality of chambers at the earth surface to apply the relatively low pressure to all of the plurality of chambers and on the earth formation from which the natural gas and liquid are produced in an evacuation phase of the gas recovery cycle.