摘要
作者提出一种处理烟气脱硫残渣的新方法。该法将脱硫残渣在硫酸溶液中转变为ＦＧＤ石膏，同时回收ＳＯ２。ＦＧＤ石膏在碱土金属盐类和硫酸的混合液中，于大气压下加热脱水生成α型半水硫酸钙。研究中发现酸浓度和温度是影响ＦＧＤ石膏脱水速度最敏感的因素；固液比虽然对脱水速度影响不大，但于晶体生长和习性改良不利；ｐＨ值愈接近中性范围，愈能增强α型半水结晶在液相中的稳定性。
A new process for conversion of flue gas desulfurization scrubbing sludge waste into FGD gypsum with dilute sulfuric acid while collection of SO 2 evolved,further into α form calcium sulfate hemihydrate by heating in an aqueous solution consisting of some alkali earth metal salts and sulfuric acid at the atmospheric pressure has been studied in this subject.It is found that the concentration of sulfuric acid in liquid and the reaction temperature are the most sensitive factors for this process.Increasing the ratio of solid to liquid is disadvantageous for growth of crystals even though it does not effect obviously for the rate of dehydration of FGD gypsum.On the other hand,the more closed to the neutral range of pH value the liquid is adjusted,the better stability of the α form calcium sulfate hemihydrate appears,the more favorable for modification of crystal habit the process is made.
关键词
烟气脱硫残渣
FGD石膏
α型半水硫酸钙
flue gas desulfurization scrubbing sludge
FGD gysum
α form calcium sulfate hemihydrate
aqueous solution process
