Phosphorus extraction and impurity reduction method for wet-process phosphoric acid

• Main Authors: TU ZHONGBING, LI JIANWEN, WANG MENGLAI, FU YIZHONG, ZHU GUIHUA, NIU SIJIANG, LIU ZHENGDONG, YANG JUN, HE BINBIN, GONG LI, ZHOU QIONGBO, YANG WENJUAN, XIE MI, JIANG WEI, GAO ZHICHENG
• Format: Patent
• Language: Chinese; English
• Published: 13.10.2023
• Subjects: CHEMISTRY; COMPOUNDS THEREOF; INORGANIC CHEMISTRY; METALLURGY; NON-METALLIC ELEMENTS

The invention discloses a wet-process phosphoric acid phosphorus extraction and impurity reduction method, and belongs to the technical field of wet-process phosphoric acid comprehensive utilization. 2) second-stage concentration of supernate; 3) second-stage concentration of filtrate; 4) after the fluorine content in phosphoric acid subjected to second-stage concentration and pre-defluorination is less than or equal to 0.4%, conveying qualified finished phosphoric acid at the bottom of a defluorination tower to a finished acid storage tank by a finished acid pump; and 5) mixing the finished product phosphoric acid clear liquid with the high-concentration calcium carbonate emulsion to produce high-quality feed calcium phosphate. P2O5 is increased to 40%-42% through segmented concentration and first-stage concentration, a large amount of slag is settled at the moment, clear acid is subjected to membrane filtration, a defluorination agent is added for second-stage concentration, first-stage slag acid is subject