Anyu Wang, Xudong Li

(School of Energy and Power Engineering, Ningbo University)

Abstract：

The multi-pass circulating fluidized bed technology is a new type of circulating fluidized bed combustion technology. It adopts a unique three-stage furnace structure to form a two-stage material circulation in the furnace, which have advantages of high efficiency, wide fuel adaptability and low initial emissions of pollutants. A lot of research on the flow and heat transfer inside the multi-pass circulating fluidized bed has been made, revealing the gas-solidity flow and heat transfer mechanisms in each furnace of the multi-pass circulating fluidized bed. Multi-pass circulating fluidized bed industrial boilers have been developed for different kinds of fuels. This paper introduced the technical characteristics of multi-pass circulating fluidized bed, and analyzed the adaptability of the technology to biomass fuel and its application status in biomass boilers. Combined with the characteristics of this technology and the status of biomass energy in China, its rational utilization in biomass boilers was discussed. It was indicated that the advantages of the original pollutant control of the technology should be fully utilized to reduce the operating cost of biomass boilers while reducing emissions.

Key Words：

multi-pass; circulating fluidized bed; biomass; industrial boiler; ultra-low emission