Title:
METHOD FOR TREATING LIQUID TO BE TREATED AND METHOD FOR RECOVERING SILVER
Document Type and Number:
Japanese Patent JP2018158325
Kind Code:
A
Abstract:
PROBLEM TO BE SOLVED: To provide a method for reducing the treatment cost of the liquid to be treated, and a method for improving the recovery rate of silver .SOLUTION: The present invention provides a method for treating an alkaline liquid to be treated, containing silver, hydrogen peroxide, and a chelating agent which is at least one of EDTA and DTPA, the method comprising: a sulfide adding step of adding a sulfide to the liquid to be treated, a heating step of heating the liquid to be treated to which the sulfide has been added, to remove hydrogen peroxide, a chelating agent adding step of adding a piperazine type chelating agent to the liquid to be treated from which hydrogen peroxide has been removed, a solid-liquid separation step of recovering a silver-containing substance as a solid by subjecting the liquid to be treated to solid-liquid separation after the chelating agent adding step, a neutralizing step of adding an acid to the liquid generated in the solid-liquid separation step to neutralize it, an evaporation concentration step of evaporating and concentrating the neutralized liquid, and a condensed water treatment step of removing formaldehyde contained in the condensed water generated by the evaporation condensation.SELECTED DRAWING: Figure 1
Inventors:
TASHIMO HIROYUKI
NAKATSUKA SEIJI
IRIE OSAMU
IDENO TAKASHI
NAKATSUKA SEIJI
IRIE OSAMU
IDENO TAKASHI
Application Number:
JP2017058489A
Publication Date:
October 11, 2018
Filing Date:
March 24, 2017
Export Citation:
Assignee:
DOWA TECH KK
International Classes:
C02F1/62; C02F1/04; C02F1/58; C02F1/70; C02F9/02; C02F9/04; C02F9/10; C02F9/14; C22B3/24; C22B3/44; C22B7/00; C22B11/00
Domestic Patent References:
| JP2004337651A | 2004-12-02 | |||
| JPH0221995A | 1990-01-24 | |||
| JPS637894A | 1988-01-13 | |||
| JPH03231921A | 1991-10-15 | |||
| JP2014053619A | 2014-03-20 | |||
| JP2011211217A | 2011-10-20 | |||
| JPS4916617A | 1974-02-14 |
Foreign References:
| US4731187A | 1988-03-15 |
Attorney, Agent or Firm:
Aniya Setsuo
Okuyama Tomohiro
Okuyama Tomohiro