Roots water ring vacuum system has remarkable energy saving effect, high vacuum degree and large air pumping volume in high vacuum region. As an important economic index of generating units, condenser vacuum is of great significance to the efficiency of the unit. According to the thermal characteristics, the efficiency of steam turbine will be reduced by 0.75% for every 1kPa vacuum drop. Therefore, how to improve the vacuum and achieve the best vacuum of condenser is the top priority of energy-saving management of each unit. This paper mainly analyzes the application of vacuum system in the injection pumping system.
What are the disadvantages of the equipment used in the condenser before?
1. The continuous regulation range of circulating water is narrow, which mainly depends on the local regulation of inlet valve and the step regulation of circulating pump operation mode, which mainly plays the role of maintaining vacuum and forms the optimal scheduling problem of circulating pump, which has little effect on improving vacuum.
2. It is difficult to reach the limit vacuum of the unit design in actual operation. Most units have the possibility and feasibility to further improve the vacuum.
3. Due to the low pumping efficiency, the water jet pumps must be put into operation in normal operation, which can not be used for standby, and the power consumption is large.
4. Unstable operation, large water consumption, low efficiency and inconvenient operation cause unnecessary loss to the economic operation of the plant.
From the safety and economic point of view, the original injection pumping system can no longer guarantee the safety of the unit. After operation, the transformation has become inevitable. Remove all the original equipment and use roots water ring vacuum system to vacuum the condenser.
Roots water ring vacuum system using water ring pump as the front stage pump is more advantageous than other vacuum pumps. It overcomes the limitation pressure difference of single water ring pump (the limit pressure of the unit is greatly improved than the water ring pump), and the disadvantages of low pumping rate under a certain pressure are overcome. At the same time, it retains the advantages of roots pump that can work quickly and has a larger pumping rate. Especially it can be used to remove a large amount of condensable steam, especially when the ability of removing condensable steam is not enough, or the solvent used can deteriorate the performance of the pump oil, or the vacuum system does not allow oil pollution. When equipped with explosion-proof motor and electrical appliances and comply with the corresponding safety rules, flammable and explosive gases can also be removed.
Roots pump water ring pump unit is widely used in vacuum system of chemical industry, food sublimation drying and high altitude simulation test.
Water ring vacuum pump is a kind of condenser vacuum equipment with excellent performance. It has strong ability of air extraction and air drying and cavitation prevention. At the same time, it has the characteristics of safe use, reliable operation, high degree of automation and small maintenance workload. In addition, roots vacuum pump does not need exhaust valve, which can extract condensable fatty acid steam, with low power and operation and maintenance costs It can reach the limit vacuum in a short time. The most important is to effectively improve the operating conditions of the condenser, improve the economy of the whole unit operation, and reduce the auxiliary power consumption.