Method and device for removing impurities in cyanogen-containing lean solution in smelting industry for removing gold and silver

• Main Authors: LYU ZHIHAO, WANG JIAOJIAO, LIANG YAN, QI KEJIN, LYU HONGTAO, CHENG XIANYANG, FENG YONGMEI, LI YUNFEI
• Format: Patent
• Language: English
• Published: 25.03.2015
• Subjects: APPARATUS THEREFOR; CHEMISTRY; CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION ORPROCESSING OF GOODS; ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; METALLURGY; PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY ORREFINING OF METALS; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE

The invention provides a method and device for removing impurities in a cyanogen-containing lean solution in the smelting industry for removing gold and silver. The device mainly comprises buffer tanks A and B, an electrolytic concentration tank and an anode liquor storage tank. The lean solution in each of the lean solution buffer tanks A and B is used as incoming water of a cathode chamber of the electrolytic concentration tank and the incoming water of a cyanide recovery chamber respectively, and A and B are interchanged according to the changes in concentration in the production process. An anion and cation exchange membrane is additionally arranged between a cathode and an anode of the electrolytic concentration tank to separate the cathode and the anode, thereby forming the cathode chamber, an anode chamber and the cyanide recovery chamber. The cyanogen-containing lean solution to be treated enters the cathode chamber of the electrolytic concentration tank, copper, zinc and other metal ions are electrolyzed in the cathode chamber, CN<-> is released, and the released CN<-> enters the cyanide recovery chamber under the action of an electric field, and is only concentrated in the cyanide recovery chamber and can neither be oxidized nor lost. Cu and Zn in the cyanogen-containing lean solution are precipitated by electrolysis in the cathode chamber, and the concentration is reduced; when the concentration is reduced to a certain degree, the buffer tanks are exchanged, a new cyanogen-containing lean solution enters the cathode chamber, and the electrolyzed low-concentration cyanogen-containing lean solution enters the cyanide recovery chamber for recovering cyanides and then is returned into a gold and silver extraction process step, thereby recycling all of the cyanogen-containing lean solution.