RU2642704C1 - Method of periodic gas compression - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: method of periodic gas compression, including a cycle of supplying the working fluid under pressure from the feed tank to the compression chamber while simultaneously displacing gas from its upper part into the pressure line through a discharge valve and, as the level of the working fluid in the compression chamber reaches its maximum position, switching the compression chamber to the drain mode, the cycle of emptying this chamber from the working fluid with simultaneous supply of compressed gas into it through a suction valve and, as soon as the level of working liquid reaches its minimum position, repetition of cycles. The cycle of emptying the compression chamber from the working fluid is carried out without stopping its supply by the pump to the compression chamber, and the emptying of this chamber from the working fluid is carried out at a flow rate exceeding the supply of the working fluid pump.

EFFECT: simplifying the method and increasing the reliability of the compressor.

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Description

The present invention relates to the field of compressor engineering and can be used in various industries.

A device is known for pumping gas, which includes a piston pump with a working and compression chambers equipped with suction and discharge valves and nozzles for supplying liquid and gas and gas, as well as for delaminating a mixture of liquid and gas (patent RU 17342 U1. Device for pumping gas. Declared on December 4, 2000. Published on March 27, 2001. BI No. 9). The separator is equipped with a float valve and is in communication with the storage tank, and the pipe for supplying liquid is placed in the compression chamber. The injection of gas from the compression chamber into the pressure line is carried out by the fluid supplied to the compression chamber by a piston pump. In the separation tank, the gas-liquid mixture is separated, after which the liquid enters the accumulator, and the gas into the pressure line.

The device has a complex design due to the need to use an additional separator gas-liquid mixture. This need is due to the cyclical nature of the piston pump and the formation of a mixture of liquid and gas in the area of their contact.

A known pump for pumping a gas-liquid mixture (AS USSR, No. 1590687. Declaration. 04.10.88. Publish. 07.09.90. BI No. 33), including two tanks for alternately pumping working fluid from them with a pump and thus creating a "liquid "Piston in them. With a decrease in the level of the "liquid" piston in one of the containers, the gas-liquid mixture is sucked into the vacant volume. In the same period, the working fluid fills another container and displaces a previously filled gas-liquid mixture into the pressure line. Upon reaching a certain level of the working fluid in the tank, the flows are switched and the working fluid is pumped to another tank, from which the cycle of displacing the gas-liquid mixture into the pressure line begins. The transfer pump itself works, thus, in a continuous mode, constantly pumping liquid that does not contain a gas phase. The disadvantages of the device are a complex and unreliable way to switch the pump from one tank to another, as well as the need to install two compression chambers.

A known method of pumping a gas-oil mixture by a volume displacement pump (A.S. SU 1079825 A. A method of pumping a gas-oil mixture by a volume displacement pump. Claim. 04/21/1982. Publish. 03/15/1984. BI No. 10). The method is based on the displacement of the pumped mixture from the chamber by the working fluid supplied by a centrifugal pump from the second chamber. During this period, the pumped mixture is sucked into the second chamber. Then the process is repeated in the opposite direction.

The disadvantage of this method is the need to use chemicals that prevent the formation of emulsions at the interface between the working fluid and the pumped. Such emulsions are formed when formation water is used as the working fluid, and the gas-oil mixture is used as the pumped medium.

Closest to the proposed solution is the installation for water-gas treatment of the oil reservoir (patent RU No. 2500003 C2. Claim. 08.22.2011. Publ. 10.12.2013), containing a centrifugal pump for pumping a working fluid without gas, receiving lines for gas and liquid, two tanks with suction and discharge valves, lines for the selection and discharge of fluid, connected with the discharge and intake of the pump. At the water inlet line, an additional pump is placed in parallel, connected to the working nozzle of the liquid-gas ejector, the receiving chamber of which is connected to the gas line, and the discharge to the upper parts of the tanks. In addition, at the inlet of the ejector, a control valve and a throttle are located, and the shut-off element of the control valve is hydraulically in communication with the ejector of the ejector and the inlet to the throttle.

After the water level in one of the tanks drops to the minimum value, the level sensor transmits a signal to switch the fluid supply in the opposite direction. Switching flows is carried out using controlled three-way valves.

The analogue selected as a prototype has the disadvantage of reducing the reliability of the pump due to the presence of solid suspended particles (HDTV) and partially oil in water. In commercial water related to aggressive media used as a working fluid and pumped by a centrifugal pump, up to 300 mg / l or more HDTV may be contained, which cause increased wear and corrosion of the pump impellers. As a result of wear, the pressure characteristic of the pump deteriorates, and ultimately its failure occurs.

In addition, the use of two compression chambers significantly complicates the design and automation of control of the installation, increases the metal consumption and reduces the reliability of its operation.

The technical task of the proposed method is to simplify the method and increase the reliability of the compressor.

The novelty of the technical solution lies in the fact that in the known method, which includes a cycle of pumping a working fluid under pressure from a supply tank into a compression chamber while simultaneously displacing gas from its upper part into a pressure line through a discharge valve and, as the working fluid reaches the compression level the chamber of maximum position, switching the compression chamber to drain, the cycle of emptying this chamber from the working fluid with the simultaneous flow of compressed gas into it through the suction cell apan and, as the level of the working fluid reaches its minimum position, cycles are repeated, according to the invention, the cycle of emptying the compression chamber from the working fluid is carried out without stopping its supply by the pump to the compression chamber, and this chamber is emptied from the working fluid at a flow rate exceeding the flow rate of the pumping fluid pump.

The figure shows a schematic diagram of the implementation of the method.

The circuit includes a compression chamber 1 with shutoff valves of the upper 2 and lower 3 positions of the level of the working fluid. The upper part of the compression chamber 1 is connected to check valves 4 and 5, mounted respectively on the suction 6 and pressure 7 gas lines of the installation. The lower part of the compression chamber 1 by line 8 is connected to the supply tank 9 through an electromagnetic valve 10 with sensors for maximum and minimum pressure (not shown in the figure) and a valve 11. A suction line 12 of the pump 13 with the filter 14 is introduced into the supply tank 13 is connected to the compression chamber 1, as well as through a safety valve 16 with a supply tank 9. Before the liquid enters the passage section of the electromagnetic valve 10 and on the discharge line 15 of the pump 13, control gauges 17 and 18 are installed.

The liquid level shutoff valves 2 and 3 in the chamber 1 are spherical floating floats overlapping the openings in the chamber 1, respectively, in its upper and lower parts. For pumping a working fluid, a volume displacement pump, such as a gear pump, is used, and, for example, synthetic oil can be used as a working fluid.

The electromagnetic valve 10 opens its flow area when it reaches the maximum permissible pressure value and closes the flow area when the minimum acceptable value is reached

The method is as follows.

The cyclic filling of the chamber 1 with a working fluid and its emptying allows you to change the pressure and volume of gas in it above the liquid level. When the pressure drops below the pressure in the suction line 6, gas enters the chamber 1, and when it reaches a pressure above the pressure in the pressure line 7, the gas is forced out of the chamber 1.

In the suction cycle (idle period of the pump 13), gas enters the chamber 1 through the check valve 4. The check valve 5 remains closed due to the excess pressure in the pressure line 7 over the pressure in the chamber 1.

In the gas injection cycle, the liquid level in the chamber 1 and the pressure in it increase due to the pump 13 supplying the working fluid and the gas is forced into the pressure line 7 through the check valve 5. In this cycle, the working fluid from the supply tank 9 through the intake line 12 and the filter 14 enters a pump 13, which pumps the working fluid into the chamber 1 along the pressure line 15. During this period, the bore of the electromagnetic valve 10 remains closed. When the liquid level in chamber 1 reaches its highest position, the float of the shut-off valve 2 will pop up and block the gas outlet in the upper part of chamber 1. The pressure in chamber 1 will increase sharply due to the continued operation of pump 13. When the maximum pressure is reached, the maximum pressure sensor will trigger and the solenoid valve 10 will open the passage for draining the liquid. The discharge of fluid from the chamber 1 through line 8 through the valve 11 into the supply tank 9, which is under atmospheric pressure, will occur under gas pressure, approximately equal to the pressure in the suction line 6 of the installation. When the liquid level in the chamber 1 reaches its lowest position, the float of the valve 3 will lower and block the hole for draining the liquid in the chamber 1. The pressure at the inlet to the electromagnetic valve 10 will sharply decrease and, when the permissible value is reached, it will block its passage section.

The discharge of fluid from the chamber 1 will occur during continuous operation of the pump 13, i.e. his idle work period. To minimize the period of idle operation of the pump 13, the flow rate of the drained liquid is set significantly higher than its flow. This flow rate is achieved by appropriate selection of the diameters of the passage sections of the electromagnetic valve 10 and line 8. In addition, this flow rate is also achieved by setting the minimum allowable pressure value in the suction line 6. A small allowable pressure value in the suction line 6 (for example, 0.2 ... 0 , 25 MPa) allows you to get the discharge costs of the working fluid from the chamber 1, which is a multiple of the supply of the pump 13. The flow rate of draining the fluid from the chamber 1 to the supply tank 9 is regulated by a valve 11.

After the passage section of the electromagnetic valve 10 is closed, due to the non-stop operation of the pump 13, the liquid level in the chamber 1 will rise and the cycle will be repeated again, etc. To prevent emergency situations when the pressure rises sharply in the chamber 1 after the gas outlet is closed, the safety valve 16 is provided by the float of the valve 2. If the pressure is exceeded above the permissible value, the safety valve 16 will open and the liquid from the pump 13 will enter directly into the supply tank 9.

By adjusting the supply of the pump 13, the volumes of gas compression can be changed.

The constant mode of operation of the pump 13 significantly increases the reliability of its operation and MTBF by reducing the frequency of starts and stops, as well as loads on the drive motor.

Techno-economic advantages of the method are simplicity, low metal consumption and high reliability of operation of the equipment used.

Claims (1)

A method of periodically compressing gas, including a cycle of pumping a working fluid under pressure from a supply tank into a compression chamber while simultaneously displacing gas from its upper part into a pressure line through a discharge valve and, as the working fluid level in the compression chamber reaches its maximum position, switching the compression chamber to drain, the cycle of emptying this chamber from the working fluid with the simultaneous flow of compressed gas into it through the suction valve and, as achieved by the level of the working fluid level of the minimum position, the cycle is repeated, characterized in that the cycle of emptying the compression chamber from the working fluid is carried out without stopping its supply by the pump to the compression chamber, and this chamber is emptied from the working fluid with a flow rate exceeding the flow rate of the pump pumping the working fluid.

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