考察了湿法磷酸生产过程中Si, F, K和Na等杂质对CaSO4结晶过程的影响规律. 结果表明，两种碱金属对CaSO4结晶有不同作用，K有利于CaSO4晶体生长，而Na含量增加则会抑制CaSO4团聚；不同形式的K, Si和F对CaSO4结晶的作用不同，SiO2对CaSO4粒径影响不大，但会使其形貌不规则，H2SiF6会造成CaSO4晶体分散，而K2SiF6有利于CaSO4晶体生长.
The effects of impurities such as Si, F, K and Na on the crystallization process of calcium sulfate in wet-process phosphoric acid were investigated. The results showed that two types of alkali metals had different effects on the crystallization of calcium sulfate. The addition of K was beneficial for the growth and agglomeration of the crystals, and the increase of Na content inhibited the agglomeration of calcium sulfate. The particle size was barely affected by the amount of silica except the irregular shape, and the addition of H2SiF6 can lead to the diversion of the particles. K2SiF6 had a synergistic effect on the particles to improve the growth of calcium sulfate crystals.
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