Thread Content
Flue gas desulfurization technologies can be divided into two main categories based on their process characteristics: wet and dry methods. The wet methods mainly include the limestone/lime method and the double-alkali method, etc. Dry methods mainly include spray drying, circulating fluidized bed dry flue gas desulfurization, and activated carbon/active coke catalytic oxidation adsorption methods. Compared to the two methods, the advantage of the wet method is lower operating costs. The advantage of the dry method is that there are no issues such as secondary treatment of wastewater; the purified flue gas can be discharged directly at a high temperature, whereas in the wet method the flue gas must be reheated before it can be discharged. Desulfurization methods can be divided into two main categories based on whether the sulfur-containing products are recovered: the disposal method, in which such products are discarded as solid waste, and the recovery method, in which they are recovered as by-products. The main advantages of the abandonment method are: simpler equipment, easier operation, and lower investment and operating costs. The main disadvantage of the disposal method is that it occupies a large amount of space and is prone to causing secondary pollution. When the SO2 concentration in the flue gas is low, or when investment is limited, the abandonment method is commonly used. The main advantage of the recovery method is that it recovers SO2 from flue gas as a sulfur resource, turning waste into treasure while avoiding secondary pollution. The main disadvantages are: complex processes, high difficulty in operation, and high investment and operating costs. When the SO2 concentration in the flue gas is high, the recovery method can be considered. The limestone/lime method is divided into four categories: limestone/disposal method, lime/disposal method, limestone/gypsum method, and lime/gypsum method