摘要
以钢铁厂烧结过程产生的脱硫石膏为原料,采用超声辅助清洗和乙醇溶液脱水的方法制备半水硫酸钙。通过单因素实验和正交实验研究了液固比、溶液浓度、温度和搅拌时间等工艺条件对脱硫石膏除杂效果的影响,以及不同的乙醇浓度和脱水时间对纯化后的脱硫石膏含水量的影响。实验结果表明,超声辅助清洗除杂最佳条件为:首先在液固比为2∶1、碱浓度15%、50℃恒温搅拌0.5 h的条件下进行碱洗除杂;然后在液固比为1.5∶1、酸浓度为5%、30℃恒温搅拌0.5 h的条件下进行酸洗除杂;最后在氧化剂用量为2%、50℃恒温搅拌1.5 h的条件下进行氧化除杂。在此条件下得到的石膏中硫酸钙含量为96.01%,含水量为12.41%。当乙醇浓度大于50%时,随着浓度的增加,脱水效果会降低,而脱水时间与脱水效果正相关。在乙醇浓度50%,脱水时间为15 h时即可获得较好的半水硫酸钙产物。
By ultrasonic assisted cleaning and ethanol solution dehydration, calcium sulfate hemihydrate was prepared by using the desulfurization gypsum produced during the sintering process of the steel plant as raw material. The effects of processes such as liquid-solid ratio, solution concentration,temperature and stirring time on the desulfurization effect of gypsum,as well as the effects of different ethanol concentrations and dehydration times on the moisture content of raw materials were studied by univariate experiments and orthogonal experiments. The results show that the best conditions for ultrasonic cleaning and impurity removal are: liquid to solid ratio is 2∶1,alkali concentration is 15%,and alkali eluted impurities is carried out at 50 ℃ constant temperature by stirring for 0.5 h;liquid to solid ratio is 1.5∶1, acid concentration is 5%, and acid eluted impurities is carried out at 30 ℃ constant temperature by stirring for 0.5 h;oxidation eluted impurities is carried out at 50 ℃ constant temperature with 2% of oxidant by stirring for 1.5 h. The calcium sulfate content of the gypsum obtained under this condition was 96.01%, and the water content was 12.41%. When the ethanol concentration is higher than 50%,the dehydration decreases as the concentration increases, and the dehydration time is proportional to the dehydration effect.When the ethanol concentration is 50% and the dehydration time is 15 hours,good calcium sulfate products can be obtained.
作者
刘宗奇
吴相龙
吴娜
向小艳
LIU Zongqi;WU Xianglong;WU Na;XIANG Xiaoyan(Schoo of Metalurgy and Materials Engineering.Chongqing University of Science and Technology,Chongqing 401331,China)
出处
《金属材料与冶金工程》
CAS
2022年第6期53-60,共8页
Metal Materials and Metallurgy Engineering
关键词
脱硫石膏
除杂
恒温脱水
半水硫酸钙
desulfurized gypsum
impurity removal
constant temperature dehydration
calcium sulfate hemihydrates
作者简介
第一作者:刘宗奇(2001-),男,本科,主要研究方向为资源循环与利用。;通讯作者:向小艳(1982-),男,副教授,博士,主要研究方向为资源循环与利用。
