Large Power Station Boiler Soot Blowing Optimization

During operation of coal fueled power plant boiler, heat exchange surfaces will be polluted by soot accumulation. This seriously weakened the heat transfer capability from gas to working fluid. Usually, soot blowers are used in large boilers to clean heat exchange surfaces. Large amount of energy are consumed during soot blower operation, and frequent unsuitable soot may damage or shorten the life of heat exchange surfaces because of wear and thermal stress. At the same time, the maintenance cost of soot blowers are increased. Therefore, it makes a great sense to find an optimal operating method of soot blowers to make the total loss minimum caused by soot accumulation and by energy consumption of soot blowers in order to decrease the cost of power generation.This article investigates optimization method of boiler soot blow system and the carry out of optimization system. The heat balance method is used to establish heat loss calculating model and to find an optimal interval of soot blowing which is most economic. In this way, no additional measure points are needed. Through online calculation using online data, soot blow time and soot blowers group on operation are changed timely to get the best economic income.The article takes a 600MW natural cycle drum boiler (soot blow using steam) as investigating object, establishes soot accumulation loss and soot blowing energy loss models for its water cooling wall, superheater, economizer and air preheater respectively, set up instructions for soot blower operating. Simulating calculation results are compared with site data to verify usefulness of key models.The article introduced the operation optimizing design of soot blowers of Yanzhou No2 Power Plant based on theoretical research. After the optimizing system is put into operation, online calculating results and operation effect is analyzed, pointing out that the base for the whole boiler soot blow optimization is the minimum loss of soot accumulation and energy consumption of soot blowing, the base for water cooling wall soot blow optimization is the combustion house outlet gas temperature difference, the base for a single heat exchange surface soot blow optimization is the degree of its soot accumulation.