Three Factors Affect Limestone Desulfurization Efficiency
In the desulfurization process of powder plant, limestone powder is the most commonly used desulfurizing agent. The limestone desulfurization efficiency will directly affect the quality and efficiency of powder production process. And there are several factors that affect limestone desulfurization efficiency in powder plant. In this article, we mainly introduce these factors.
1. Quality Of Limestone
Generally, the content of calcium carbonate in limestone should be above 85%. If the calcium carbonate content is too low, it will cause some problems for the desulfurization because of the impurities in limestone, leading to the increase of absorbent consumption and transportation cost. The quality of limestone is decided by the content of CaO. The higher the purity of limestone, the higher the desulfurization efficiency will be. While designing the desulfurization process, the technique designer should not only calculate the chemical component of limestone, but also should know its physical properties.
The calcium oxide in the prime limestone should be between 48%~54%. But for the calcium oxide in limestone is not like the higher the better. For limestone with calcium oxide content above 54%, it will marbleize because of the high purity. Besides, it is hard to be ground and has stable chemical properties, which makes it not suitable to be used as desulfurizing agent.
2. Fineness Of Limestone
The fineness of limestone powder is a very important factor that affects the desulfurization efficiency. In desulfurization process, to a large extend, the contact area decides the speed of chemical reaction. The finer of the limestone powder size, the larger the superficial area will be, so does the contact area of chemical reaction for per unit weight. Since the reaction rate of limestone is in proportion with its surficial area, so finer limestone particles has better ablation performance. In this case, the related reaction speed is also relatively higher, so does the desulfurization efficiency and use rate of limestone.
3. Reactivity Of Limestone
As desulfurizing agent, the properties of limestone include not only its chemical components but also its reactivity. The reactivity of limestone affects its solubility and dissolution rate. Under same use rate, limestone with higher reactivity has higher desulfurization efficiency to remove the SO2. Besides, when the reactivity of limestone is high, the use rate of limestone will also be high.
