Coaxial pumping apparatus with internal power fluid column

Abstract

The present application relates generally to pumps, and more particularly to piston type pumps having increased energy efficiency, systems incorporating such piston type pumps, and methods of operating piston type pumps.

What is claimed is: 
     
         1 . A pumping apparatus, comprising:
 a first inlet having an inlet valve;   an outlet for product fluid, the outlet having a pressure maintaining valve;   an accumulator in fluid communication with the pressure maintaining valve;   an internal power fluid column, the internal power fluid column having a second inlet;   a transfer piston reciprocatingly mounted about the power fluid column;   a product fluid chamber positioned above the transfer piston;   a transfer chamber positioned below the transfer piston;   a sealable channel in the transfer piston fluidly connecting the product fluid chamber and the transfer chamber, the sealable channel having a transfer piston valve; and   at least one passageway fluidly connecting the power fluid column with a power fluid chamber.   
     
     
         2 . The pumping apparatus of  claim 1 , wherein the apparatus is configured to pressurize fluid inside the power fluid column and the power fluid chamber. 
     
     
         3 . The pumping apparatus of  claim 2 , wherein the transfer piston is configured such that the fluid acts against a first area comprising at least a portion of the transfer piston in a direction of transfer piston movement. 
     
     
         4 . The pumping apparatus of  claim 3 , wherein the first area is greater than a second area comprising at least a portion of the transfer piston in the power fluid chamber, and wherein the transfer piston is configured such that the fluid in the power fluid chamber acts against the second area in a direction of movement of the transfer piston. 
     
     
         5 . The pumping apparatus of  claim 1 , further comprising a first valve stop configured to prevent closing of the inlet valve and a second valve stop configured to prevent closing of the transfer piston valve. 
     
     
         6 . The pumping apparatus of  claim 5 , wherein at least one of the first valve stop and the second valve stop comprises an extended portion on the rod portion of the transfer piston or a v-shaped member configured to prevent the transfer piston valve from closing when the v-shaped member contacts an activator. 
     
     
         7 . The pumping apparatus of  claim 1 , wherein the power fluid column is internal and the power fluid chamber, the transfer chamber and the product chamber are situated coaxially about the power fluid column. 
     
     
         8 . The pumping apparatus of  claim 1 , configured for use in a deep well, wherein the system is configured to operate using a power fluid comprising water or a hydraulic fluid. 
     
     
         9 . The pumping apparatus of  claim 8 , wherein at least one of the power fluid chamber and the power fluid column comprises stainless steel or titanium. 
     
     
         10 . The pumping apparatus of  claim 1 , further comprising a solenoid valve configured to control oscillation of a high head, whereby oscillating pressure to the power fluid is delivered. 
     
     
         11 . The pumping apparatus of  claim 1 , further comprising a fluid inlet screen configured to filter fluid entering the first inlet. 
     
     
         12 . The pumping apparatus of  claim 1 , further comprising a coaxial disconnect. 
     
     
         13 . The pumping apparatus of  claim 1 , further comprising a subterranean switch pump comprising a power hydraulic line and a recovery hydraulic line. 
     
     
         14 . The pumping apparatus of  claim 1 , further comprising a power fluid within the power fluid column and power fluid chamber. 
     
     
         15 . The pumping apparatus of  claim 1 , wherein the accumulator is a transfer barrier accumulator configured to control timing of pressure applied alternatingly on the power fluid column and on the product fluid column. 
     
     
         16 . The pumping apparatus of  claim 1 , further comprising a housing, wherein the first inlet, the outlet, and the internal power fluid column are disposed within the housing, wherein the transfer piston slidably and sealingly extends between the power fluid column and an interior wall of the housing, and wherein the product fluid chamber and the transfer chamber are at least partially defined by the interior wall of the housing. 
     
     
         17 . The system of  claim 16 , further comprising a coaxial disconnecting device, wherein the coaxial disconnecting device is separately sealed to the power fluid column and the product fluid chamber, whereby fluid communication between the power fluid column and the coaxial disconnecting device is provided, and whereby fluid communication between the product fluid chamber and the coaxial disconnecting device is provided. 
     
     
         18 . A method for pumping a fluid, the method comprising:
 introducing a power fluid into the power fluid chamber of a pumping apparatus of  claim 1  via the internal power fluid column, whereby the transfer piston is lifted so as to close the transfer piston valve, whereby fluid to be pumped is drawn into the transfer chamber via the inlet valve;   decreasing a pressure of the power fluid in the power fluid column and the power fluid chamber, whereby the transfer piston falls, the transfer piston valve is opened, and the inlet valve is closed, whereby the fluid to be pumped passes from the transfer chamber via the transfer piston valve into the product fluid chamber; and   increasing the pressure of the power fluid in the power fluid column and the power fluid chamber, whereby the transfer piston is raised, and the transfer piston valve closes, such that fluid to be pumped in the product chamber is forced out of the product chamber, such that the power fluid is pumped, wherein the accumulator provides force over that created by a head of the internal power fluid column.   
     
     
         19 . The method of  claim 18 , wherein the pressure of the power fluid is increased and decreased through application of an oscillating pressure to the power fluid by moving a piston back and forth in a cylinder containing the power fluid, and wherein motion of the piston is induced by operation of at least one device selected from the group consisting of a motor, an engine with a crank mechanism, a pneumatic device, and a hydraulic device. 
     
     
         20 . The method of  claim 19 , wherein providing oscillating pressure to the power fluid comprises providing a column of power fluid extending to an elevation higher than an elevation at which product fluid is recovered, wherein introducing a power fluid into a power fluid chamber of a pumping apparatus via an internal power fluid column comprises closing a valve to a power fluid source and opening a power fluid release valve at an elevation lower than an elevation at which the pumped fluid is recovered, whereby the power fluid is introduced into the power fluid chamber.