Experimental Study on Microstructure of Fly-Ash from Circulating Fluidized Bed Boilers
Circulating fluidized bed (CFB) combustion techniques have been widely used in China. In order to improve CFB boiler performance it is necessary to study on microstructures of fly-ash. With the help of nitrogen adsorption instrument and scanning electron microscopy, the pore structure of fly-ash in circulating fluidized bed boilers are studied by nitrogen adsorption/desorption isotherms of fly-ash, hysteresis loop and pore distribution. The results indicated that different particle sizes of fly-ash in CFB boilers are of similar nitrogen adsorption isotherms, pore types and the pore size distribution, and the most probable pore radius of fly-ash is about 2nm. Adsorption isotherms of fly-ash is the second type, and the macro-porous and meso-porous types are tapered hole, parallel plate slit hole and the ink bottle shape hole. And meso-pore in proportion is the largest. Micro-pores are not discovered in fly-ash from CFB boilers.
Hao Zhang, Yang Fu and Zhong Tang
Y. Jin et al., "Experimental Study on Microstructure of Fly-Ash from Circulating Fluidized Bed Boilers", Advanced Materials Research, Vols. 354-355, pp. 413-416, 2012