热电厂余热利用条件下热网调节方式优选

Optimal Selection of Heat-supply Network Regulation Modes under Waste Heat Utilization in Thermal Power Plants

对热电厂余热利用技术(溴化锂吸收式热泵余热利用、汽轮机高背压余热利用)进行介绍。基于溴化锂吸收式热泵余热利用技术,结合算例,对不同热网调节方式(质调节、分阶段改变流量质调节、质量并调、量调节)下一级管网的运行技术经济性进行比较。采用质调节方式时,供暖期一级管网流量不变,管网水力工况稳定,运行管理简便。虽然输送成本比较高,但总运行成本(包括能源成本、输送成本)在4种调节方式中最低。在4种调节方式中,质调节方式对排汽余热的利用量最大,对汽轮机的抽汽耗量最小,对发电量的影响最小,技术经济性最优。

The technologies for waste heat utilization in thermal power plants （utilization of lithium bromide absorption heat pump waste heat and steam turbine high back pressure waste heat） are introduced. Based on the lithium bromide absorption heat pump waste heat utilization technology, the technical and e- conomical efficiencies of the operation of primary cir- cuit under different adjustment modes of heat-supply network （ constant flow control, centralized control with flow varied by steps, integrative flow control and varia- ble flow control） are compared combined with exam- ples. When the constant flow control is adopted, the flow of the primary circuit is constant in the whole heating period, the hydraulic regime of the primary cir- cuit is stable, and the operation and management are simple and convenient. Although the transportation cost is relatively high, the total operating cost including energy cost and transportation cost is the lowest among the four regulation modes. The constant flow control in four regulation modes has the largest utilization rate of exhaust heat, the smallest extraction steam consumption of turbine and the smallest impact on power generation, with the optimal technical and economic efficiencies.