Screw Vacuum Pump in Oil and Gas Recovery of Gas Station of Application
First of all, popularize the oil and gas recovery device.
In the process of loading and unloading gasoline and refueling vehicles, the volatile gasoline oil and gas are collected, and the purpose of recovery and utilization is achieved by one or two methods, such as absorption, adsorption or condensation, or by reducing the pollution of oil and gas, or by converting oil and gas from gaseous to liquid and back to gasoline.
Oil and gas recovery is a high and new technology of energy saving and environmental protection. Oil and gas recovery technology is used to recover oil and gas discharged during storage, transportation and handling, to prevent air pollution caused by oil and gas volatilization, to eliminate potential safety hazards, and to reduce economic losses by improving the utilization rate of energy, so as to obtain considerable returns. At present, the common methods of oil and gas recovery devices are adsorption, absorption, condensation and membrane separation systems.
Oil and gas recovery system consists of three parts: quick joint and cap at the bottom of tank, manual or pneumatic valve, elbow and seamless steel pipe; seamless steel pipe passing through the bottom and top of tank, or external pipeline connection system; elbow at the top of tank, manual or pneumatic valve, rubber pipe, parallel head, elbow returning into tank body, etc. Key power equipment: dry screw vacuum pump provides power.
So why can screw vacuum pump be used in the field of flammable and explosive oil and gas recovery? Mainly screw vacuum pump has the following characteristics:
1. Clean vacuum can be obtained without any medium in the working chamber.
2. The surface of pump chamber and screw rotor has anticorrosive coating, which can be used in harsh working conditions.
3. The rotating parts have no friction and can run at high speed with small volume.
4. The exhausted gas is directly removed from the pump body to facilitate tail gas recovery without environmental pollution.
5. Dry vacuum unit can be formed with Roots pump.
6. Good Kaide Dry Screw Vacuum Pump can remove inflammable and explosive gases.
The application of dry screw pump in the field of oil and gas recovery is a kind of environmental protection equipment in petrochemical industry – gasoline vapor recovery device. At present, this kind of equipment is in trial production stage in China, and there are many mature applications in Europe and America.
The extracted gas is volatile gasoline vapor, the main components are C4, C5, C6 and other gasoline vapors, so there are explosion-proof requirements in the field, the explosion-proof grade is usually Ex D IIB T4; the operation temperature of the pump is usually required to be controlled below 60 degrees C, and the alarm temperature is 80 degrees C. It is necessary to have a liquid injection port (at the highest temperature) in the pump chamber, which can inject appropriate amount of gasoline when the pump is running, so as to evaporate and absorb heat to reduce the temperature in the pump chamber; cooling water can not be provided on most sites, and the cooling liquid can be supplied as gasoline; some customers require frequency conversion control.
The process of oil and gas recovery system mainly includes three processes:
1) Oil vapor is adsorbed in the adsorption tower.
2) Vacuum regeneration of adsorption tower by dry vacuum pump;
3) Absorbing high concentration hydrocarbon vapor in absorption tower
Screw-type oil-free mechanical vacuum pump, also known as dry-type screw vacuum pump, is a high-speed rotation of the left screw and the right screw by means of synchronous reverse rotation of gear transmission. The spiral groove is separated into several spaces and formed into several stages by using the pump shell and the spiral meshing each other, and the gas is 6 (cylindrical equal pitch) in the same groove.
The transmission motion is carried out, but there is no compression. Only the helical structure at the end of the screw can compress the gas. Pressure gradient can be formed between screw stages to disperse pressure difference and increase compression ratio. The clearance of each part and the speed of the pump have a great influence on the performance of the pump. Expansion, machining and assembly accuracy and working environment should be taken into account when designing clearance between screw parts.
(e.g. the removal of dusty gases, etc.). The pump has no exhaust valve like Roots vacuum pump. If this type of pump chooses the proper simpler screw tooth section, it will be easy to manufacture, ensure high processing accuracy and easy to dynamic balance.
The pump is a horizontal structure. The screw rotor is hollow and cantilever supporting structure. The synchronous transmission gear is located under the bearing support. The variable frequency motor is connected with the active rotor through the coupling. The gas path of the pump is shorter, and the vertical structure is more favorable for eliminating the gas containing dust.
When the screw vacuum pump is running, there is no water or oil in the pump chamber. Because of the direct ventilation design, the pump can handle the gas containing condensable vapor and the gas containing tiny particles without remaining in the pump. Because there is no contact between metal and metal in the pump chamber, the wear is greatly reduced. Screw pumps are water-cooled systems, air-cooled systems for choice.
Chemical and pharmaceutical processes