Research on Improving Flexibility of Thermal Power Units by Flue Gas-water Heat Exchanger

Abstract

The proportion of renewable energy in the power supply structure of Shandong power grid is increasing day by day. Thermal power units inevitably face deep-peak shaving and frequent-peak shaving. The problem of thermal power contradiction is prominent when thermal power units are heating in winter, which has a negative impact on the security and stability of power grid and the consumption of renewable energy. Traditional thermoelectric decoupling technology has some problems such as narrow load adjustment range and poor overall energy utilization efficiency. A scheme of adding flue gas-water heat exchanger is proposed to supplement the traditional IP cylinder extraction technology for heating. According to the calculation, the minimum electric power of flue gas heating mode is significantly lower than that of traditional heating mode under small heating demand, and the maximum and minimum electric power of hybrid heating mode are better than that of traditional heating mode under the same heating demand, and the maximum heating capacity under the mixed heating mode is significantly increased, which can improve the operation flexibility of the unit and enhance the thermoelectric decoupling ability of the unit.