Thermal Power Plant Of Rotary Air Preheater Retrofit

Air preheater is an important auxiliary equipment in the boiler of power plant, it carries the function of reducing smoke temperature and improving the temperature of the two air of the hot air and the air. It’s heat transfer performance of high and low, directly affect the boiler efficiency, but also power plant boiler safe and stable operation plays a vital role. However with long time run off implementation of denitrification transformation, as well as equipment, air preheater heat exchange element of blockage and leakage rate increases and the cold end corrosion increased, not only of air preheater heat transfer performance produced certain influence, but also the crisis to the safe and stable operation of the air flue gas system.In this paper, by means of 2* 600MW Subcritical air cold northern power company of a tangentially fired combustion thermal power plant after the transformation of denitrification air pre heater problems analysis and research, found that there are three main problems, continuous air pre heater operation for a long time the original seal device for wear serious, air leakage control system of frequent fault input rate is low, caused by a large amount of air leakage of air preheater and, as a result, the boiler efficiency decreased; second, after boiler denitrification transformation, due to ammonia escape caused by blockage in air preheater and the original steam blowing ash device can not solve the problem. Northern Coal and different power plant for cost saving a large number of mixed burning high moisture lignite, air pre heater heat transfer ability is insufficient, heat wind temperature low mill insufficient drying capacity and blending ratio is limited.In view of the above problems, a series of reform and reform of the air preheater is carried out.Reformation scheme of the first proposed the air preheater of flexible contact seal and leakage control system. After the transformation through the air preheater air leakage test to verify the effect after transformation, and the air pre heater are equipped with high frequency soot blower, and through the transformation and operation parameters of air preheater of comparison, we can draw the conclusion, namely air pre heater install acoustic sootblowers, by setting reasonable blowing ash frequency, so that air preheater differential pressure control at around. At last, the air preheater is transformed, and the area of the hot primary air is enlarged, and the temperature of the air temperature is raised by 20 degrees centigrade, and the proportion of lignite is improved.