Study on Heat Transfer Characteristics in 350MW Supercritical CFB Boiler

Rui Yang; Ye Chen; Nenghong Zheng; Tao Liu

doi:10.62051/ijmee.v3n1.04

Authors

Rui Yang
Ye Chen
Nenghong Zheng
Tao Liu

DOI:

https://doi.org/10.62051/ijmee.v3n1.04

Keywords:

350MW Supercritical CFB Boiler, Temperature Measurement, Heat Transfer Coefficient, Heat Flux

Abstract

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.

References

Chen W, Fang X, Xu Y, et al. An assessment of correlations of forced convection heat transfer to water at supercritical pressure [J]. Annals of Nuclear Energy, 2015, 76: 451-460.

Kitoh K, Koshizuka S, Oka Y. Refinement of transient criteria and safety analysis for a high-temperature reactor cooled by supercritical water[J]. Nuclear Technology, 2001, 135(3): 252-264.

Pan J, Yang D, Dong Z, et al. Experimental investigation on heat transfer characteristics of smooth tubes at low mass flux under subcritical and nearcritical pressure[J]. Gaojishu Tongxin/chinese High Technology Letters.

Chen J C. Correlation for Boiling Heat Transfer to Saturated Fluids in Convective Flow [J]. Industrial & Engineering Chemistry Process Design & Development, 1962, 5(3): 322-329.

Andersson B, Bo L. Experimental methods of estimating heat transfer in circulating fluidized bed boilers [J]. International Journal of Heat & Mass Transfer, 1992, 35(12): 3353-3362.

Blaszczuk A, Nowak W, Jagodzik S. The impact of bed particle size in heat transfer to membrane walls of supercritical CFB boiler [J]. Archives of Thermodynamics, 2014, 35(3): 207-223.

Zhang R, Yang H, Zhang H, et al. Research on heat transfer inside the furnace of large scale CFB boilers[C]. 10th International Conference on Circulating Fluidized Beds and Fluidization Technology, 2014.