调整抽汽式机组高背压供热技术经济性分析

近些年来,热电联产在城市集中供热的方式中所占比例逐渐增长,为了进一步提高热电联产机组在冬季供暖期间的经济性,提高供热机组的供热能力,加强节能减排效果,在现有热电联产机组装机容量基础上,对汽轮机进行供热节能改造是供热机组的发展趋势,而高背压循环水供热则是利用汽轮机低压缸供热改造而发展的一项节能环保技术,可使燃料利用率达90%以上。通过已经改造机组的运行情况看,高背压供热工况下机组具有较好的热效率、发电煤耗等。通过理论计算分析,在不受供热面积、供热管径等条件的限制下,对某厂两台300 MW 调整抽汽机组进行高背压改造,改造后全厂的供热能力可达到800 MW,机组供热能力和经济性有较大的提升,为北方同类型机组提供借鉴意义。

The Economic Analysis to High Back Pressure Heating Technology Related to Adjust Steam Extraction Unit

In recent years,proportion of combined heat and power generation in urban centralized heating has been increased year by year.In order to improve the economic benefit of cogeneration units during win-ter heating,increase the heating capacity of the units,and improve energy saving effect,the heating energy-saving transformation to steam turbine on the basis of existing cogeneration units is trend of heating unit development.While the high back pressure circulating water heating is an energy-saving and environment protection technology that is to use heating transformation to low-pressure cylinder in steam turbine.It can make the fuel efficiency more than 90%.Through the operation of the transformed units,we got the con-clusion that the units under high back pressure condition has better thermal efficiency,coal consumption, etc..Through theoretical calculation and analysis,high back pressure transformation has been made on two 300 MW adjust steam extraction unit without the limitation toheating area,heating pipe diameter and other conditions.The whole plant heating capacity has been up to 800 MW after the transformation,the units heating capacity and economy have greatly improved,which will provide reference for the same type of unit in north part of China.