| 摘要 |
FIELD: production of phosphotizing solutions and salts. SUBSTANCE: method comprises evaporating wet-process phosphoric acid, treating it with apatite concentrate, adding coagulant, clarifying and subsequently separating condensed precipitate from product. Evaporation involves using wet-process phosphoric acid containing 34-40% P<SB>2</SB>O<SB>5</SB>. Phosphoric acid is evaporated to P<SB>2</SB>O<SB>5</SB> concentration of 52- 57% F to F:P<SB>2</SB>O<SB>5</SB> and SO<CHF>2@4</CHF><SP>-</SP>:P<SB>2</SB>O<SB>5</SB> weight ratio in acid after evaporation is within 0.003-0.008 and 0.02-0.05, respectively. Acid is then treated with apatite concentrate so as to maintain SO<CHF>2@4</CHF><SP>-</SP>:P<SB>2</SB>O<SB>5</SB> weight ratio in acid at 0.003-0.010. After treatment with apatite concentrate, wet-process phosphoric acid is clarified. Clarification rate is 0.18-0.24 m/h. During purification, sulfate content is reduced from 1.1-2.4 to 0.15-0.5% calculated for SO<CHF>2@4</CHF> . EFFECT: more efficient purification method. 2 cl, 4 ex, 1 tbl
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