Study on Heat Transfer Characteristics in 350MW Supercritical CFB Boiler

Supercritical circulating fluidized bed boiler has the advantages of good environmental performance and high efficiency of units, which is suitable for large-scale promotion and has a bright commercial application prospect. It is the inevitable choice of clean coal power generation technology in our country at present. When the steam parameter of CFB boiler is raised from 300 MW sub-critical to 350 MW supercritical parameter, the characteristics of steam water in the heating surface tube screen and the gas-solid flow and combustion heat transfer characteristics in the furnace have great changes, and the overall structure and system layout of the boiler also have significant differences, which brings about changes in the heat transfer characteristics in the furnace. In this paper, the heat transfer coefficient of the working medium in the tube and the heat flux distribution in the furnace are obtained by measuring the temperature on the back fire side of the water wall. The results show that the furnace height increases from 6000W/ (m2·℃) to 31000 W/ (m2·℃). The heat flux in the furnace decreases with the increase of furnace height.