前置暖风器电站锅炉烟气余热回收系统多参数 设计与变工况运行策略

The calculation model of the multi-parameter design optimization and variable working conditions was developed for the waste heat recovery system of the pre-heater of coal-fired unit. The multi-parameter optimization for the system was performed. The control strategy of operating parameters was proposed. Results show that the coal-saving rate of the optimized system under the design condition is 3. 67 g/ (kW • h). Although the multi-parameter optimized system can maintain a high coal-saving rate under off-design working conditions, the safety is seriously restricted by the ambient temperature and unit load. The proposed control strategy can extend the lower limit of environmental temperature for safe operation of the system from 24 "C to —3 "C at 100% rated load, which significantly improves the comprehensive effect of system optimization.