燃煤锅炉双效低低温省煤器技术的应用研究

The Application Study of Double-effect Lower Temperature Economizer in the Coal Fired Boiler

为解决低低温省煤器出现的积灰、换热面磨损及泄露问题,对热力系统参数、结构参数以及系统运行控制3个方面的关键因素进行研究分析,提出一种双效低低温省煤器系统。将该系统应用在某循环流化床机组,并对换热器的结构参数进行了优化,对其经济性进行了全面分析。结果表明：该系统可实时控制换热器运行参数,有效实现烟气余热回收。系统投运后,机组年节约标准煤量919.5 t,回收热量6. 83×10^4 GJ,系统投运后可降低烟尘、CO2、SO2和NOx等污染物的排放,节能效益和环保效益显著。

To solve the dust accumulation and abrasion and leakage of the lower temperature economizer, the parameters of the thermodynamic system and structure and the operation control were studied, and a system of double-effect lower temperature economizer was put forward. This proposed system was applied to a CFB unit, and the parameters of the structure were optimized and the economic performances were comprehensively analyzed. The results indicated that the system can constantly control the operating condition of the economizer, while recovering the fuel heat efficiently, with the proposed system, the consumption of standard coal can be reduced by 919.5 t each year, and 6.83 × 10^4 GJ heat is recovered each year. Meanwhile,the emission of the dust and carbon dioxide and sulfur dioxide and nitrogen oxides can be reduced. In summary, the presented system is significant efficient in energy conservation and environ- mental protection.