A Novel Inertial Separator for CFB Boilers

Besides several cyclone separators, some inertial separators had also developed and applied in the circulating fluidized bed (CFB) boilers. The inertial separators have some advantages such as simple structure, small volume, low pressure drop, easy scale-up and so on. But almost every existing inertia separator has great difficulty in solving the main shortage of lower separation efficiency especially for fine particles. Based on the research for the separation mechanism and performances of inertial separators, the State Key Laboratory of Coal Combustion (SKLCC) had developed a novel inertial separator for CFB boilers. The patented separator improves the structure of the U-beam that is the separation element of U-beam separators of Studsvik Energiteknik (Sweden) and Babcok & Wilcox (USA). A ash channel is added to avoid re-entrainment of the separated solid downward along the U-beam. Test result indicates that the novel separator has great higher separation efficiency with the same pressure drop, compared with the U-beams at same conditions. The novel separator is more suitable for a larger CFB boiler or repowering projects as primary separator than the U-beams. The novel inertial separator had been used for designing 25 ∼ 420 tons of steam per hour (t/h) two-stage-recirculation CFB boilers. The two-stage-recirculation CFB boilers in capacity of 25 t/h and 65t/h had been put into operation. This paper presents the work on research, development and application of the novel inertial separator with high separation efficiency and low pressure drop.