改性消石灰吸收剂用于干法脱除HCl的研究

RESEARCH OF MODIFIED LIMES REACTING WITH GASEOUS HCl

特定浓度的ＮａＯＨ、Ｎａ２ＣＯ３、ＫＯＨ和Ｋ２ＣＯ３溶液消化生石灰获得改性消石灰吸收剂。在２１０～３１０℃温度段对吸收剂吸收ＨＣＩ气体的测量结果表明：改性消石灰具有更高的净化ＨＣＩ的能力，并且在低ＨＣＩ浓度下反应能力仍较高。研究初步发现产生改性的原因有：（１）改性消石灰含有其它的物相，改善了石灰的初始孔隙特性及孔隙结构随时间的变化规律；（２）改性石灰反应后的产物中不出现ＣａＣｌ·２Ｈ２Ｏ或其含量极低，Ｃａ（ＣＩＯ）２·ｘＨ２Ｏ和ＣａＣｌ２是主要的反应产物，有利于提高反应率；（３）与纯消石灰的产物层相比，改性石灰的产物层更疏松多孔化。

Several modified slaked limes were obtained by lime hydration in NaOH, KOH, Na2CO3 and K2CO3 water solutions of special concentrations. At temperature region of 210 - 310℃, the HCI retention capabilities of these modified limes had been tested and were found greatly enhanced. Furthermore, the retention capabilities of those modified limes remained high values under the condition of lower initial HCI concentrations. Investigations showed that unknown crystals have been formed in modified slaked limes and their products, which improve pore structures of both the limes and their product layers, and that none CaCl·2H2O was produced when most of modified limes reacting with HCl, instead, Ca(CIO)2·xH2O and CaCl2 were main products, which favors the reaction. SEM pictures showed that product layers of modified limes are more porous than that of pure lime.