Limestone particle size (fineness) on the FGD system performance: ground limestone powder can increase the surface area per unit mass of limestone powder, while maintaining the same pH and the same absorption tower desulfurization rate, FGD system at a high limestone utilization of run conditions, calcium oxide desulfurization, gypsum by-product quality will be better. Depending on the degree of calcination of limestone, calcium oxide how much money one ton species generally can be divided into: light (soft) burnt lime, calcium oxide, hard burnt lime and dead-burned lime. Light (soft) burnt lime means: lime calcination after moment, with a so-called active properties. Concept in lime, used to distinguish between different types of them, the most obvious way is to different degrees of activity.