文献类型：期刊文献

英文题名：Melt suspension crystallization for purification of phosphoric acid

作者：Chen, Aimei[1];Zhu, Jiawen[1];Chen, Kui[1];Wu, Bin[1];Ji, Lijun[1];Wu, Yanyang[1]

机构：[1]E China Univ Sci & Technol, Chem Engn Res Ctr, Shanghai 200237, Peoples R China

年份：2013

卷号：8

期号：3

起止页码：354

外文期刊名：ASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING

收录：;EI(收录号：20132516425965);WOS:【SCI-EXPANDED(收录号:WOS:000320113600007)】；

基金：The author gratefully acknowledges the financial support from the Eleventh Five-Year National Science and Technology Supporting Major Project (2007BAE58B03) PRC and West Region Project of Shanghai Science and Technology (10195801600).

语种：英文

外文关键词：suspension crystallization; phosphoric acid; gravity wash column; purification

摘要：A continuous melt suspension crystallization process has been presented for the purification of the phosphoric acid in this study, which is conducted in the cascade of a continuous mixed suspension and mixed product removal (MSMPR) crystallization and subsequent countercurrent solid-liquid contact in a gravity wash column. With magma withdrawn from the MSMPR crystallizer being fed into the top of the gravity wash column, crystals settle down toward the bottom of column and the reflux melt rises upward, whereas the sweating of crystals and counter-current contact between crystal particles and the melt lead to high separation capability of impurities. The gravity wash column used in this study is a vertical agitated cylindrical column, whose configuration is different from the inclined column crystallizer. The feasibility of suspension crystallization equipment for purification of phosphoric acid was studied. Distribution of impurities in the wash column was also investigated as a function of the feed concentration, crystal bed height, reflux ratio and stirring speed. Reflux ratio has been found to play an important role in the process. Food grade phosphoric acid can be achieved when the process is operated with feed concentrations of 84 similar to 86wt.%, reflux ratios of 3.4 similar to 6.2, stirring speed of 10rpm and crystal bed height of 150 similar to 250mm in a gravity wash column. (c) 2012 Curtin University of Technology and John Wiley & Sons, Ltd.