The structure of the screw vacuum pump has developed a set of vacuum pumping device which is mainly used in the waste heat power generation project. After repeated testing and improvement by the technician, it can completely replace the previously used water jet pumping device without affecting the vacuum degree of the system. The operation characteristics of screw vacuum pump in the application process of waste heat power generation and the working principle of screw vacuum pump.
What is the definition of waste heat power generation?
Waste heat power generation refers to the technology of converting surplus heat energy into electric energy in the production process. Waste heat power generation is not only energy-saving, but also conducive to environmental protection. The important equipment of HRSG is HRSG. It uses heat or combustible substance in working medium such as waste gas and waste liquid as heat source to produce steam for power generation. Because the working medium temperature is not high, the boiler has a large volume and consumes a lot of metal. The waste heat for power generation mainly includes the waste heat of high temperature flue gas, chemical reaction, waste gas, waste liquid and low temperature, which is lower than 200 ℃.
The transmission shaft is connected with the active rotor, and the driven rotor is driven to rotate by the synchronous gear. A cooling water channel is opened on the shell to cool the temperature of the rotor and the exhaust port. The synchronous gear and the bearing are lubricated by oil. The bearing and the shell are sealed by seals to achieve the effect of no oil. The structure of dry screw vacuum pump is similar to that of oil-free screw compressor in sealing and lubrication. Generally, mechanical seals are used at the exhaust end of vacuum pump, and double lip seals are commonly used at the inlet side. In terms of transmission mode, the current general purpose is direct connected motor, which is connected with the rotor by coupling, and very few are driven by belt or drive chain. Due to no internal compression process, the exhaust temperature of constant pitch screw pump is very high. If the cooling effect is not good, the rotor and casing will be deformed, which will affect the pumping effect. Cooling the shell is an essential part, and water cooling is the most common method. Cooling water can be passed through the shell body and the outside of the bearing to cool the shell and then the rotor.
In view of the current situation, the vacuum pump is modified by adding a pre injection device, which increases the reliability of the equipment operation, but when the vacuum pre injection device operates, the current increases a lot, which can not achieve the energy-saving effect. The vacuum tightness of screw vacuum pump is good, the amount of air leaking into condenser is very small in normal operation, the vast majority of extracted gas is water steam, and the required power is less, so the installation of screw vacuum pump instead of the original running equipment can achieve the purpose of energy saving and vibration elimination.
With the technology of waste heat power generation becoming more and more mature, the state attaches importance to energy, supports energy conservation and emission reduction, more and more enterprises that can use waste heat realize the benefits of waste heat power generation. The application of screw vacuum pump in waste heat power generation this mode not only solves the shortage of funds and technology, but also makes the waste gas, tail gas and waste heat reasonably used.