Reconstruction And Economic Analysis Of 300MW Pumping And Condensing Unit With High Back Pressure Heating

At the beginning of the colder in winter in north China,at the end of the cold period of about 40～45 days,the cold period of 130～135 days,heating period for up to six months,these areas of outdoor temperatures are below zero in winter,have higher request for the heating quality,so in these areas need to draw condensed air cooling unit for research,after transforming the cogeneration of heating unit on the one hand,through the turbine power generator,on the other hand to the outside network provides a certain temperature and pressure of the steam,the energy utilization rate is higher,so the air cooling unit heating reform both economically and significant energy saving ways.Stake power company currently unit heating area of 900000 square meters,the next step to solve stake industrial companies and thousands of wuhai city hills heating demand of 3.2 million square meters,this can make stake power companies at present the problem of insufficient heating ability,the task of the heating period heating also reached the maximum heating ability,and will affect power generation task.Through the analysis and study of the original heating mode of Mengxi Power Generation Company,this paper solves the problem of increasing heating demand by adopting the heating retrofitting method of high back pressure.It only needs to add the condenser used in the heating season without changing the current structure and operation mode of the unit.Not only solve the heating problem,but also improve the overall thermal economy and economic benefits of the power plant.Through analyzing different heat loss allocation methods of research,combined with related data at home and abroad,based on the first law of thermodynamics,the heat method of modified high back pressure for the analysis of thermal efficiency of heating unit,calculate smoke condensation heating way and the way of high back pressure heating capacity,power standard coal consumption rate,generating heat consumption rate and power generation efficiency indicators,when the heating heat load cases,high back pressure heating extraction steam heating coal consumption saving 40.8 g/k Wh,heatingperiod every year if prices for 200 yuan/ton,can cut down the cost of Biao Mei consumption of 881300 yuan.The thermal efficiency of power generation is increased by19.03%,the fuel utilization coefficient is increased by 11.68%,and the generating capacity can be increased by 78000 k W compared with that of direct steam extraction for heating.At the same time,the high back pressure heating method is to directly use the exhaust steam to heat the heating circulating water,which can reduce the steam extraction capacity of the medium-pressure cylinder and thus reduce the overall cold source loss of the unit,thus significantly improving the overall efficiency of the unit.