초록 ▼

The invention is a subsea pump that includes pumping elements, each pumping element including a pressure vessel with a first and a second chamber therein and a separating member disposed between the first and second chambers. The first and second chambers are hydraulically connected to receive and d

The invention is a subsea pump that includes pumping elements, each pumping element including a pressure vessel with a first and a second chamber therein and a separating member disposed between the first and second chambers. The first and second chambers are hydraulically connected to receive and discharge a hydraulic fluid and a drilling fluid, respectively. The separating member moves within the pressure vessel in response to a pressure differential between the first and second chambers. A hydraulic power supply is arranged to pump the hydraulic fluid to the first chamber of each of the pumping elements. A valve assembly is hydraulically coupled to the first chambers of the plurality of pumping elements and to the hydraulic power supply. Volume measurement devices are arranged to measure volumes of each of the first chambers and the second chambers. A valve controller is connected to the valve assembly and to the volume measurement devices, and the valve controller is arranged to control a rate and timing of a flow of the hydraulic fluid into the first chambers and a rate and timing of a flow of the hydraulic fluid out of the first chambers in response to the volume measurements. The valve controller is configured to maintain at least one of a substantially constant pump inlet pressure, a substantially constant pump discharge pressure, and a substantially constant total volume of the first chambers.

대표청구항 ▼

The invention is a subsea pump that includes pumping elements, each pumping element including a pressure vessel with a first and a second chamber therein and a separating member disposed between the first and second chambers. The first and second chambers are hydraulically connected to receive and d

The invention is a subsea pump that includes pumping elements, each pumping element including a pressure vessel with a first and a second chamber therein and a separating member disposed between the first and second chambers. The first and second chambers are hydraulically connected to receive and discharge a hydraulic fluid and a drilling fluid, respectively. The separating member moves within the pressure vessel in response to a pressure differential between the first and second chambers. A hydraulic power supply is arranged to pump the hydraulic fluid to the first chamber of each of the pumping elements. A valve assembly is hydraulically coupled to the first chambers of the plurality of pumping elements and to the hydraulic power supply. Volume measurement devices are arranged to measure volumes of each of the first chambers and the second chambers. A valve controller is connected to the valve assembly and to the volume measurement devices, and the valve controller is arranged to control a rate and timing of a flow of the hydraulic fluid into the first chambers and a rate and timing of a flow of the hydraulic fluid out of the first chambers in response to the volume measurements. The valve controller is configured to maintain at least one of a substantially constant pump inlet pressure, a substantially constant pump discharge pressure, and a substantially constant total volume of the first chambers. ll fluid communication between the chamber and the central passageway. 8. The method of claim 6, wherein the determining includes: receiving the well fluid in the chamber. 9. The method of claim 6, further comprising: automatically, selectively controlling well fluid communication between another annular chamber of the tubing and the central passageway of the central section of the tubing, said another chamber partially circumscribing the central section a region of the central section not circumscribed by the first chamber. 10. The method of claim 6, wherein the determining includes using a material responsive to a predetermined composition, and wherein the controlling includes using the material to alter the well fluid communication based on the presence of the predetermined composition. erein expansion of liquid CO2in the landfill gas well as it enters a well screen of the landfill gas well dislodges bridging and fouling material in and around the well screen. 14. The method of claim 12, wherein the injection of the CO2mixture is injected until a predetermined volume is injected. 15. The method of claim 12, wherein the injected CO2mixture cleans mineral encrustation in the landfill gas well, pressurizes the landfill gas well and cleans and creates passages in the landfill gas well. 16. The method of claim 7, wherein CO2cycling achieves a higher pressure with each CO2injection. 17. The method of claim 1, wherein non-liquefied CO2gas is pressurized and depressurized to backwash and flush a sell screen of landfill gas well. 18. The method of claim 1, further comprising dislodgment of bacterial growths and associated by-products from the landfill gas well. 0, Morita et al., 361/753; US-5670009, 19970900, Tarn et al., 156/299; US-5708297, 19980100, Clayton, 257/723; US-5731633, 19980300, Clayton et al., 257/723; US-5751553, 19980500, Clayton, 361/749; US-5776799, 19980700, Song et al., 438/118; US-5811879, 19980900, Akran, 257/723; US-5875068, 19990200, Sawada, 360/099.01; US-5881453, 19990300, Avery et al., 029/834; US-5932065, 19990800, Mitchell, 156/556; US-5953588, 19990900, Camien et al., 438/106; US-5959840, 19990900, Collins et al., 361/713; US-5983644, 19991100, Bolandi et al., 062/003.2; US-6017776, 20000100, Jiang et al., 438/118; US-6136128, 20001000, Chung, 156/235; US-6204093, 20010300, Ahmad, 438/119