Study On Auto-sulfur Retention Of High-calcium Coal Fied In Power Plant

Auto-sulfur retention property of high-calcium coal is embodied as salt-chemical reaction of acid oxides and alkaline oxides in this study.It is effected by coal sulfur, calcium oxide content and Ca-S ratio. The auto-sulfur retention ratio decreases with an increase of coal sulfur and increases with increasing calcium oxide content. When the Ca-S ratio is less than 3, the auto-sulfur retention ratio increases with an increase of the Ca-S ratio, but it is adverse when the Ca-S ratio is more than 4. The effect of potassium oxides and sodium oxides on auto-sulfur retention ratio is little. The effect of combustion way, burning atmosphere, and other factors should also be considered in large utility for pulverized coal fired boilers. In addition, the relationship between auto-sulfur retention ratio of high-calcium and Ca-S ratio is found. The auto-sulfur retention ratio is about 20% through analysis of one power plant case. By comparing the calculation methods of the auto-sulfur retention ratio, the recommendations for the operation of high-calcium coal boiler and the design of FGD are made.