Title:
PROCESS FOR REGENERATING ACID FROM STAINLESS STEEL MIXED ACID WASTE LIQUID
Document Type and Number:
WIPO Patent Application WO/2020/108028
Kind Code:
A1
Abstract:
The present invention belongs to the technical field of mixed acid waste liquid regeneration, and relates to a process for regenerating acid from stainless steel mixed acid waste liquid, comprising feeding mixed acid waste liquid into a pre-concentration displacement device for pre-concentration treatment and displacement reaction; absorbing HF gas with water to form hydrofluoric acid, and subjecting the hydrofluoric acid and metal nitrates in the mixed acid waste liquid to displacement reaction to produce nitric acid and fluoride salts; directly contacting the mixed acid waste liquid and high-temperature flue gas generated by means of high-temperature decomposition in a reaction furnace to perform heat exchange, nitric acid in the mixed acid waste liquid being evaporated into the high-temperature flue gas, a concentrated liquid of the mixed acid waste liquid being obtained, and at the same time, washing solid particles in the high-temperature flue gas and separating same; feeding the concentrated liquid of the mixed acid waste liquid into the reaction furnace again for high-temperature decomposition; and feeding the high-temperature flue gas after dust has been separated into an absorption tower, and rinsing same by spraying water such that HF and HNO3 in the high-temperature flue gas are adsorbed by water, so as to form regenerated acid. The process for regenerating acid from stainless steel mixed acid waste liquid provided by the present invention performs pre-concentration treatment and displacement reaction in a pre-concentration displacement device, thereby improving the recovery of nitric acid.
Inventors:
ZHAO JINBIAO (CN)
WANG JUN (CN)
DING YU (CN)
GAO JUNFENG (CN)
WU ZONGYING (CN)
WANG JUN (CN)
DING YU (CN)
GAO JUNFENG (CN)
WU ZONGYING (CN)
Application Number:
PCT/CN2019/106442
Publication Date:
June 04, 2020
Filing Date:
September 18, 2019
Export Citation:
Assignee:
WISDRI ENGINEERING & RES INCORPORATION LIMITED (CN)
International Classes:
C01B21/38; C02F1/02
Foreign References:
| CN209338121U | 2019-09-03 | |||
| CN109553152A | 2019-04-02 | |||
| CN109467065A | 2019-03-15 | |||
| CN207713438U | 2018-08-10 | |||
| CN107601605A | 2018-01-19 | |||
| CN104086464A | 2014-10-08 | |||
| EP0775760A1 | 1997-05-28 |
Attorney, Agent or Firm:
BEIJING HUIZE INTELLECTUAL PROPERTY LAW LLC (CN)
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