Patent Publication Number: US-9890771-B2

Title: Gas operated booster pump

Description:
TECHNICAL FIELD 
     The present invention relates to a subsidiary apparatus of oil and gas exploitation engineering, and more particularly to an isentropic booster and the method thereof. 
     BACKGROUND ART 
     In the field of natural gas gathering and transportation engineering, it is well known that some gas sources may have a pressure lower than the pressure of gas pipeline network, which causes the gas thereof fail to enter the gas pipeline network, whilst the pressure of other gas sources in the same area is higher than the pressure of gas pipeline network. For a long time, people have been involved in development of techniques which use residual pressure of high-pressure gas sources to boost pressure of the low-pressure gas, so that the pressure of the high-pressure gas source and the low-pressure gas source can achieve the pressure of the gas pipeline network simultaneously and enter the gas pipeline network. A commonly used technique is high-pressure gas injection. However, this technique has a very low efficiency of utilization of high-pressure gas pressure. Several times or even dozens of times of the high-pressure gas will be necessary to inject a part of low-pressure gas. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide an isentropic booster with more efficient use of high-pressure gas. 
     According to an aspect of the invention, an isentropic booster is provided which comprises a main body pump having a work chamber being separated into a plurality of independent booster chambers by a fixed division plate, a left piston, a right piston and a connecting rod provided therein. The connecting rod passes through the division plate and connects at its two opposite ends with the left piston and the right piston respectively. The volume of the booster chambers is variable with the movement of the left piston and the right piston. A part of the plurality of the booster chambers connect between high-pressure gas source and a medium-pressure gas pipeline network, and the rest of the plurality of the booster chambers connect between low-pressure gas source and the medium-pressure gas pipeline network. 
     According to another aspect of the invention, an isentropic booster is provided which comprises a main body pump and first to fourth three-way valves. The main body pump has a work chamber inside. The work chamber is provided with a division plate, a left piston located on the left to the division plate, a right piston located on the right to the division plate, and a connecting rod passing through the division plate and being connected at the left end thereof with the left piston and at the right end thereof with the right piston, first to fourth booster chamber being formed in sequence from left to right by separating the work chamber with the division plate, the left piston and the right piston. The main body pump is provided with first to fourth air inlets and first to fourth air outlets, the first air inlet and the first air outlet communicating with the first booster chamber, the second air inlet and the second air outlet communicating with the fourth booster chamber, the third air inlet and the third air outlet communicating with the second booster chamber, and the fourth air inlet and the fourth air outlet communicating with the third booster chamber. A first port of the first three-way valve communicates with high-pressure gas source, a second and a third ports of the first three-way valve each communicates with the first and the second air inlets; a first port of the second three-way valve communicates with the medium-pressure gas pipeline network, a second port and a third port of the second three-way valve each communicates with the first air outlet and the second air outlet; a first port of the third three-way valve communicates with the low pressure gas source, a second and a third ports of the third three-way valve each communicates with the third and the fourth air inlets; a first port of the fourth three-way valve communicates with the medium-pressure gas pipeline network, and a second and a third ports of the fourth three-way valve each communicates with the third and fourth air outlets. 
     According to a further aspect of the invention, a method of boosting is provided which comprises connecting a high-pressure gas source and a low-pressure gas source to a medium-pressure gas pipeline network through a main body pump. The main body pump comprises a work chamber being separated into a plurality of independent booster chambers by a fixed division plate, a left piston, a right piston and a connecting rod provided therein. The connecting rod passes through the division plate and connects at its two opposite ends with the left piston and the right piston. The volume of the booster chambers is variable according to the movement of the left piston and the right piston. The method further comprises that, in a cycle of operation of the main body pump, the high-pressure gas source and the low-pressure gas source communicate with the medium-pressure gas pipeline network respectively via the independent booster chambers of the main body pump. 
     According to the above arrangements, in one cycle, the gas of high-pressure well enters the first booster chamber through the first air inlet via the first three-way valve, the gas of low pressure well enters the third booster chamber through the fourth air inlet via the third three-way valve. With both high-pressure and low-pressure gas, the left and right of the pistons and the connecting rod move to the right, pressing the gas of the second and fourth booster chambers into the medium-pressure gas pipeline network. The gas of the fourth booster chamber is high-pressure gas injected in the previous cycle, and the gas of the second booster chamber is low-pressure gas injected in the previous cycle. At this time, the pressure of the gas of second and fourth booster chambers equals to the pressure of the medium-pressure gas pipe network as the second and the fourth booster chambers communicate with the medium-pressure gas pipeline network, which ultimately realizes a higher efficiency of use of high-pressure gas source. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic view of the main body pump of an isentropic booster according to an embodiment of the present invention; and 
         FIG. 2  is a schematic view of an isentropic booster according to an embodiment of the present invention. 
     
    
    
     DESCRIPTION OF EMBODIMENT(S) OF THE INVENTION 
     Some embodiments of the present invention will be described in detail in the following with reference to the drawings. It should be noted that the following description is for the purpose of illustration of the invention only but are not intended to limit the scope of the invention. 
     As shown in  FIGS. 1 and 2 , an isentropic booster according to an embodiment of the present invention comprises a main body pump  100  having a work chamber therein, a first three-way valve  1 , a second three-way valve  2 , a third three-way valve  3  and a fourth three-way valve  4 . The work chamber is provided therein with a fixed division plate  5 , a left piston  6  located on the left of the division plate, a right piston  7  located on the right of the division plate, and a connecting rod  8  which passes through the division plate  5  and connects at its two opposite ends with the left piston  6  and the right piston  7  respectively. The division plate  5 , left piston  6  and right piston  7  separate the work chamber of main body pump  100  into first to fourth booster chamber  9 ˜ 12  positioned from left to right and not communicated with each other. 
     The main body pump  100  is provided with a plurality of inlets and outlets. First air inlet  13  and first air outlet  17  communicate with the first booster chamber, second air inlet  14  and second air outlet  18  communicate with the fourth booster chamber  12 , third air inlet  15  and third air outlet  19  communicate with the second booster chamber  10 , and fourth air inlet  16  and fourth air outlet  20  communicate with the third booster chamber  11 . 
     Referring to  FIG. 2 , a first port  101  of the first three-way valve  1  connects with a high-pressure gas source  21 , a second port  102  and a third port  103  of the first three-way valve  1  respectively connect with the first air inlet  13  and the second air inlet  14 . A first port  201  of the second three-way valve  2  connects with a medium-pressure gas pipeline network  22 , a second port  202  and a third port  203  of the second three-way valve  3  respectively connect with the first air outlet  17  and the second air outlet  18 . A first port  301  of the third three-way valve  3  connects with a low pressure gas source  23 , a second port  302  and a third port  303  of the third three-way valve  3  respectively connect with the third air inlet  15  and the fourth air inlet  16 . A first port  401  of the fourth three-way valve  4  connects with the medium-pressure gas pipeline network  22 , a second port  402  and a third port  403  of the fourth three-way valve  4  respectively connect with the third air outlet  19  and fourth air outlet  20 . The first to the fourth three-way valves  1 ˜ 4  are controlled by a conventional programmable controller (not shown) respectively. 
     With the above arrangement, in one cycle of boosting operation, the first three-way valve  1  opens so that the first port  101  and the second port  102  communicate with each other and gas from high-pressure well  21  enters the first air inlet  13 . Meanwhile, the third three-way valve  3  opens so that the first port  301  and the third port  303  communicate with each other and gas from low-pressure well  23  enters the fourth air inlet  16 . Thus, gas from high-pressure well  21  enters the first booster chamber  9  through the first air inlet  13  via the first three-way valve  1 , and pushes the connecting rod  8  and the right piston  7  to move towards the right. At this time, the volume of the second booster chamber  10  is reduced, whilst the volume of the third booster chamber  11  is increased, so that the gas of the low-pressure gas source  23  enters into the third booster chamber  11  through the fourth air inlet  16  via the third three-way valve  3 . With the combined action of both high-pressure and low-pressure gas, the left piston  6 , the right piston  7  and the connecting rod  8  move towards the right, and press the gas of the second booster chamber  10  and the fourth booster chamber  12  into medium-pressure gas pipeline network  22  via the fourth three-way valve  4  through the third air outlet  19  and the second air outlet  18  respectively. When the right piston  7  reaches the right end of the work chamber, the cycle finishes. 
     In the next cycle, the first three-way valve  1  opens so that the first port  101  and the third port  103  communicate with each other and gas from high-pressure well  21  enters the second air inlet  14 . Meanwhile, the third three-way valve  3  opens so that the first port  301  and the second port  302  communicate with each other and gas from low-pressure well  23  enters the third air inlet  15 . Thus, low-pressure gas enters the second booster chamber  10 , and the high-pressure gas enters the fourth booster chamber  12 . The pressure of the first booster chamber  9  and the third booster chamber  11  equal to the pressure of the medium-pressure gas pipe network due to the communication of the first booster chamber  9  and the third booster chamber  11  with the medium-pressure gas pipeline network, which ultimately improves the effect of better use of high-pressure gas. In this way, a bidirectional boosting is realized through the bidirectional movement of the connecting rod  8 . 
     The above descriptions are only embodiments of the present invention. It should be noted that those of ordinary skill in the art can make various improvements and variants without departing from the concept, spirit and scope of the present invention, all such improvements and variants are intended to be within the scope of the present invention.