Pumping A Multiphase Fluid Using A Pneumatic Pump

Abstract

A system and methods for pumping a multiphase fluid using a pneumatic pump are described herein. The method includes separating a multiphase fluid into a gas stream and liquid streams, and flowing a liquid stream into a pressure vessel of a pneumatic pump until a liquid level within the pressure vessel reaches a specified high level. The method also includes compressing the gas stream to form a high-pressure gas and pressurizing the pressure vessel by the flowing high-pressure gas into the pressure vessel until a pressure level within the pressure vessel reaches a specified high level. The method further includes pumping the liquid stream from the pressure vessel to a destination until the liquid level within the pressure vessel drops to a specified low level, wherein the high-pressure gas provides a motive force for pumping the liquid stream.

What is claimed is: 
     
         1 . A method for pumping a multiphase fluid using a pneumatic pump, the method comprising:
 separating a multiphase fluid into a gas stream and liquid streams;   flowing a liquid stream into a pressure vessel of a pneumatic pump until a liquid level within the pressure vessel reaches a specified high level;   compressing the gas stream to form a high-pressure gas;   pressurizing the pressure vessel by the flowing high-pressure gas into the pressure vessel until a pressure level within the pressure vessel reaches a specified high level; and   pumping the liquid stream from the pressure vessel to a destination until the liquid level within the pressure vessel drops to a specified low level, wherein the high-pressure gas provides a motive force for pumping the liquid stream.   
     
     
         2 . The method of  claim 1 , wherein pumping the liquid stream from the pressure vessel to the destination comprises converting the high-pressure gas to low-pressure gas and venting the low-pressure gas from the pressure vessel. 
     
     
         3 . The method of  claim 2 , wherein the high-pressure gas is flowed into the pressure vessel from a gas compression system, and wherein the low-pressure gas is vented from the pressure vessel to the gas compression system. 
     
     
         4 . The method of  claim 1 , comprising:
 opening a first valve to flow the liquid stream into the pressure vessel; and   closing the first valve when the liquid level within the pressure vessel reaches the specified high level.   
     
     
         5 . The method of  claim 1 , comprising:
 opening a second valve to flow the high-pressure gas into the pressure vessel; and   closing the second valve when the pressure level within the pressure vessel reaches the specified high level.   
     
     
         6 . The method of  claim 1 , comprising:
 opening a third valve to pump the liquid stream out of the pressure vessel; and   closing the third valve when the liquid level within the pressure vessel reaches the specified low level.   
     
     
         7 . The method of  claim 1 , wherein the pressure vessel comprises a power cylinder. 
     
     
         8 . The method of  claim 1 , comprising performing the method for a plurality of pressure vessels within the pneumatic pump. 
     
     
         9 . The method of  claim 1 , wherein a control system is configured to direct execution of the method. 
     
     
         10 . A system for pumping a multiphase fluid, comprising:
 a separation system configured to separate a multiphase fluid into liquid streams, a gas stream, and a solid;   a gas compression system configured to compress the gas stream; and   a pneumatic pump configured to:
 allow a liquid stream to flow into a power cylinder of the pneumatic pump until a liquid level within the power cylinder exceeds a specified high level; 
 allow the gas stream to flow into the power cylinder until a pressure level within the power cylinder reaches a specified high level; and 
 pump the liquid stream out of the power cylinder until the liquid level within the power cylinder reaches a specified low level, wherein the gas stream provides a motive force for pumping the liquid stream out of the power cylinder. 
   
     
     
         11 . The system of  claim 10 , wherein the pneumatic pump is configured to allow the gas stream to flow out of the power cylinder until the pressure level within the power cylinder reaches a specified low level. 
     
     
         12 . The system of  claim 10 , wherein the pneumatic pump comprises a plurality of valves for controlling the flow of the gas stream and the liquid stream. 
     
     
         13 . The system of  claim 12 , wherein the plurality of valves comprise solenoid valves. 
     
     
         14 . The system of  claim 10 , comprising controlling a functioning of the pneumatic pump via a control system. 
     
     
         15 . The system of  claim 14 , wherein the control system comprises a distributed control system or a programmable logical controller, or any combination thereof. 
     
     
         16 . The system of  claim 10 , wherein the multiphase fluid comprises a hydrocarbon fluid comprising oil, water, hydrocarbon gas, and sand. 
     
     
         17 . The system of  claim 16 , wherein the liquid stream comprises the oil or the water. 
     
     
         18 . A method for transporting oil using a pneumatic pump, the method comprising:
 separating a multiphase hydrocarbon fluid from a hydrocarbon production system into oil, hydrocarbon gas, water, and sand within a separation system;   flowing liquid from the separation system into a power cylinder of a pneumatic pump, wherein the liquid comprises the oil or the water, or both;   flowing the hydrocarbon gas from the separation system into a compression system;   pressurizing the power cylinder by flowing the hydrocarbon gas from the compression system into the power cylinder; and   pumping the liquid from the power cylinder to a pipeline, wherein the hydrocarbon gas provides a motive force for pumping the liquid.   
     
     
         19 . The method of  claim 18 , comprising pressurizing the hydrocarbon gas within the compression system. 
     
     
         20 . The method of  claim 18 , comprising flowing the liquid from the separation system into the power cylinder until a liquid level within the power cylinder reaches a specified high level. 
     
     
         21 . The method of  claim 18 , comprising flowing the hydrocarbon gas from the compression system into the power cylinder until a pressure level within the power cylinder reaches a specified high level. 
     
     
         22 . The method of  claim 18 , comprising pumping the liquid from the power cylinder to the pipeline until a liquid level within the power cylinder reaches a specified low level. 
     
     
         23 . The method of  claim 18 , comprising venting the hydrocarbon gas from the power cylinder to the compression system until a pressure level within the power cylinder reaches a specified low level. 
     
     
         24 . The method of  claim 18 , wherein the multiphase fluid comprises condensate, crude oil or produced water, or any combinations thereof. 
     
     
         25 . The method of  claim 18 , wherein the multiphase fluid is contaminated with erosive particulates.