Device and method for compressing a low-pressure gas

Abstract

The device (100) for compressing a low-pressure gas comprises:at least one compression chamber (105) comprising:an inlet (110) for low-pressure gas,an outlet (115) for high-pressure gas,an inlet (120) for fluid,an outlet (125) for fluid, anda piston (130) located between the gas inlet and outlet, on the one hand, and the fluid inlet and outlet, on the other hand;a fluid movement means (135) positioned on a fluid circuit connecting a fluid outlet and a fluid inlet of a compression chamber; anda means (165) for measuring the gas pressure inside the compression chamber and a circuit (160) to recirculate gas to the inlet of a compression chamber when the measured pressure is less than a predefined limit value.

1 . Device for compressing a low-pressure gas, characterized in that it comprises:
 at least one compression chamber ( 105 ) comprising:
 an inlet for low-pressure gas, 
 an outlet for high-pressure gas, 
 an inlet for fluid, 
 an outlet for fluid, and 
 a piston located between the gas inlet and outlet, on the one hand, and the fluid inlet and outlet, on the other hand; 
   a fluid movement means positioned on a fluid circuit connecting a fluid outlet and a fluid inlet of a compression chamber; and   a means for measuring the gas pressure inside the compression chamber and a circuit to recirculate gas to the inlet of a compression chamber when the measured pressure is less than a predefined limit value.   
     
     
         2 . Device according to  claim 1 , which comprises a check valve configured to prevent a return of gas in a gas inlet. 
     
     
         3 . Device according to  claim 1 , which comprises a fluid retention valve configured to retain the fluid in a compression chamber. 
     
     
         4 . Device according to  claim 1 , wherein the movement means is configured such that the pressure of the exiting fluid is between 30 and 70 bar. 
     
     
         5 . Device according to  claim 1 , wherein the movement means is a pump. 
     
     
         6 . Device according to  claim 1 , which comprises a plurality of compression chambers in series for the fluid circuit, a fluid outlet of one compression chamber being connected to a fluid inlet of another compression chamber. 
     
     
         7 . Device according to  claim 1 , which comprises a plurality of compression chambers in series for the gas, each compression chamber comprising a gas inlet and outlet independent of any other compression chamber. 
     
     
         8 . Device according to  claim 1 , which comprises a means for measuring the gas pressure inside the compression chamber and a means for opening the compression chamber gas outlet as a function of the measured pressure. 
     
     
         9 . Method for compressing a low-pressure gas, characterized in that it comprises:
 a step of inputting low-pressure gas into a compression chamber;   a step of inputting fluid into the compression chamber;   a step of moving a piston located between the gas inlet and a gas outlet, on the one hand, and the fluid inlet and a fluid outlet, on the other hand, in the compression chamber;   a step of outputting high-pressure gas from the compression chamber;   a step of outputting fluid from the compression chamber;   a step of moving fluid over a fluid circuit connecting a fluid outlet and a fluid inlet of a compression chamber; and   a step of measuring the gas pressure inside the compression chamber and a step of recirculating gas to the inlet of a compression chamber when the measured pressure is less than a predefined limit value.