Control Technology Of Vertical Water Wall Overtemperature Of Supercritical Boiler

In the Supercritical boile roperation process, the main security problems for the water wall is overtemperature operation. There are different situations:sometimes the overall is over temperature, sometimes the local is over temperature, and sometimes some tubes are over temperature. Overtemperature operation for a long time easy to cause water wall tube burst, which can seriously affect the safe operation of boilers. The research of supercritical boiler water wall temperature control can make a safe and stable operation for the water wall for a long time, by this way, the service life of the water wall will be improved. This way also can prevent the water wall tube burst,and the unit outage brought huge economic losses. At present,the studies on supercritical boiler water wall overheat problem often use multi pronged approach to solve fast, but there is not a set of relatively complete system to solve various multiple overtemperature problem.This paper first introduces the development of supercritical boiler water wall, the influence factors of supercritical boiler vertical water wall temperature change and the problem of excess temperature according to different characteristics of how to take effective control measures.Secondly, taking supercritical 600MW boiler and supercritical 1100MW boiler as examples,this article make a study on the problem of vertical water wall overheat in the unit startup commissioning stage and after operation. The paper deeply analyze how to detect the vertical water wall overheat, and put forward step by step method to solve the overheating problem.Thirdly, this paper introduces the conventional vertical supercritical boiler water wall temperature monitoring,on this basis, the study also found the furnace temperature field research new monitoring means such as monitoring and control system, and the supercritical boiler water wall vertical overtemperature problems how to prevent are summarized.Through the tests, include of air dynamic field? the uniformity of primary air and pulverized coal, we can find the reason for vertical water wall overtemperature, then choose the control measures.But,if there are many factors effect the problem, also need consider the boiler working conditions, that effects control measures respond characteristic.Study on supercritical boiler vertical water wall temperature control technology provides a strong guarantee for the safe and economic operation of boilers. The temperature detection and control measures of application effect are analyzed systematically summarized in this research, at the same time, provide references for the same type of supercritical boiler to solve the problem of vertical water wall overheat,and has an important guiding significance for the safe operation of the vertical water wall of ultra supercritical boiler.