Design And Research Of Heat Recovery System Of Air Compressor In Electronic Plant

First of all,this paper introduces the background of China’s energy strategy development and the current energy consumption of air compressor.It is known that the power consumption of air compressor accounts for about 6%of the national power consumption.In the field of large-scale chemical industry,mining and electronics,air compressor is the most important power equipment,and the power consumption accounts for more than 50%of the power consumption of the whole plant.However,only 15%of the energy is used to increase the potential energy of the gas.If not recycled,up to 85%of the energy will be wasted,which leads to the necessity of waste heat recovery of the air compressor.This paper takes the specific project as the research object,and studies the achievements of heat recovery of air compressor in various fields both domestic and international across the world.It is known that the heat recovery technology still has the following problems:single use after heat recovery;low heat recovery rate;project investment cycle is more than one year.Secondly,the paper introduces the structure of air compressor and the characteristics of various heat exchangers.According to the different heat demand of each workshop,it is determined that the air compressor unit of air compressor station is 6 centrifugal air compressors.Each air compressor has an exhaust capacity of 14700 m~3/h and a power consumption of 1550k W.After calculating the annual operation cost of three different adsorption dryers,zero air consumption drum air heat adsorption dryers are selected in consideration of energy saving effect.According to the process standard of compressed air,each dryer is equipped with three filters,namely,front filter,back filter and terminal filter.Then,the air compressor heat recovery system of the pure water station and the heat exchanger of the fresh air heat recovery system of the air conditioning unit are selected.It is determined that the pure water station is plate heat exchanger and the fresh air system of air conditioning unit is shell and tube heat exchanger.Finally,the heat transfer,heat transfer coefficient,logarithmic average temperature difference,heat transfer area,inlet and outlet pipe diameter,and heat exchanger resistance of plate heat exchanger in shell and tube heat exchanger are calculated.The heat recovery efficiency of the air compressor is 87.7%.Finally,this paper also introduces the application of the centrifugal air compressor waste heat recovery system in Lankao electronic factory,and analyzes the energy saving of the heat recovery system.By calculating the two design schemes of not using heat recovery system and not using heat recovery system,it is concluded that the initial investment of the project without using heat recovery system is 1.4 million yuan,and the total annual operation cost and maintenance cost is 8.94 million yuan;the initial investment of using heat recovery system is 4.03 million yuan,and the total annual operation cost and maintenance cost is 1.68million yuan.The payback period of the project investment is 6 months.