Simulation study on flue gas heat exchanger before dust collector in coal-fired power plant boiler

The heat loss of flue gas from coal-fired power plant boilers accounts for the largest proportion of boiler heat loss, and installing flue gas heat exchangers for waste heat recovery can improve the economics of power plants. The flue gas composition after coal combustion contains a certain share of fly ash, especially for lignite. Fly ash has a significant impact on the flue gas heat exchanger, causing instability in the flow field, poor heat transfer, increased wear, and other adverse effects. This article takes the flue gas heat exchanger installed in front of the dust collector as the research object, conducts simulations of the deposition of fly ash particles and heat transfer on the heating surface of the flue gas heat exchanger, and conducts optimization research on the structure of the flue gas heat exchanger’s heating surface. Based on the simulation results, corresponding conclusions are drawn, providing a basis for further optimizing and improving the flue gas heat exchanger.