In order to improve the desulfurization efficiency of CFB boiler in which the sulphur retention performance of limestone is not the best due to the relatively high bed temperature caused by consumption of inferior coal

modified limestone was proposed.The sulfur retention performance of limestone modified by three kinds of red mud from alumina plant under fluidized bed boiler temperature conditions was investigated experimentally.Facts such as effects of combustion temperature

modified ratio

particle size and calcium/sulfur ratio on sulfur retention efficiency were studied respectively.Results show that

the red mud can effectively improve the sulfur retention performance of limestone in the whole temperature range(700~1 100 ℃).The optimum result is achieved when the Ca/Me ratio is 15.Reducing the particle size and increasing the calcium/sulfur ratio can both improve the sulphur-fixing rate.Perfect desulfurization effect is obtained as the calcium/sulfur ratio being 2.