The fuel of coal-fired boiler will release some harmful substances after combustion that are harmful to human body, but also pollute the environment. Therefore, the desulfurization treatment is required for coal-fired boiler, including desulfurization before combustion, desulfurization during combustion and desulfurization after combustion. The specific operating methods are different.
Before the combustion, desulfurization mainly adopts traditional methods, such as microbial desulfurization, liquidation and coal gasification, chemical or physical coal washing, etc.
During the combustion, we can add sulfur fixation agent and binder to the coal and adopt absorbent to realize desulfurization.
After the combustion, there is a large amount of chlorine dioxide remaining in the flue gas, so the desulfurization at that time is actually flue gas desulfurization. According to the wet and dry conditions and water participation conditions of desulfurization products, there are dry method, wet method and semidry method of desulfurization technologies.
Based on comparison, wet method of flue gas desulfurization is suitable for coal-fired boiler with good effect, high efficiency and low calcium sulfur ratio. However, its disadvantages are high investment and complicated equipment and process.
