Analysis of effect of carnallite raw ore grade on its cold decomposition and crystallization of potassium chloride
Cold decomposition of carnallite is the main process of producing potassium chloride in China.However,the de-clining grade of carnallite ore has posed a challenge to the industrial development of potassium chloride.The resulting pro-cess produces potassium chloride with issues such as smaller particle size,increased tendency to aggregate,lower purity,and reduced yield.In this review,the quality of potassium ore in different regions was compared at first.The effect of raw ore quality on the salt precipitation order of the decomposition process was overviewed based on the thermodynamic phase equi-librium of the quaternary system(Na+,K+,Mg2+∥Cl--H2O)and its sub-systems.From the kinetic perspective of the decom-position-crystallization coupling process,the crucial factors and underlying mechanisms for regulating the particle size and morphologies of potassium chloride crystals during the cold decomposition-crystallization process(CDCP)of different grades of carnallite raw ore were summarized.In addition,combined with the current product standards,a novel classifica-tion method and corresponding process-selection strategy for low-sodium carnallite,sodium-containing carnallite,and high-sodium carnallite were proposed.And the new CDCP for different grades of carnallite raw ore was prospected,in the hope of providing theoretical guidance and references for the sustainable development of the industry.
carnallitepotassium chloridecold-decomposition and crystallizationwater-salt system phase equilibriumsize and size distribution
万方数据
维普
