Title:
トリアジン化合物含有廃水の処理による尿素合成方法
Document Type and Number:
Japanese Patent JP4632008
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a method for treating triazine compound-containing waste water, also recovering ammonia and carbon dioxide and utilizing them for synthesis of urea. SOLUTION: This method for synthesizing urea by treating the triazine compound-containing water comprises (A) a process of hydrolyzing a waste water having 9-12 pH and 0.5-2% triazine compound concentration under conditions of 150-300 deg.C temperature, 0.5-2 hr mean holding time and 6-10 MPa naturally generated pressure, (B) a process of separating the waste water obtained in the process (A) to a mixed gas of ammonia with carbon dioxide having 15-35 wt.% steam concentration and a bottom liquid not essentially containing the triazine compound and ammonia by a distillation operation, and (C) a process of absorbing the mixed gas of ammonia with carbon dioxide obtained in the process (B) with a process liquid from the urea-producing process for preparing an ammonia excess carbamic acid ammonium solution having 65-75 wt.% water content and feeding it to the urea-producing process.
Inventors:
Naoki Kawashita
Toshiyuki Hata
Kuramoge Satoshi
Shinsuke Yagi
Toshiyuki Hata
Kuramoge Satoshi
Shinsuke Yagi
Application Number:
JP2000303021A
Publication Date:
February 16, 2011
Filing Date:
October 03, 2000
Export Citation:
Assignee:
Nissan Chemical Industry Co., Ltd.
International Classes:
C02F1/02; C07C273/12; B01D3/00; C02F1/74; C07C275/02; C07C275/04
Domestic Patent References:
| JP44006273B1 | ||||
| JP11209353A | ||||
| JP51126967A | ||||
| JP46014453B1 | ||||
| JP57106672A | ||||
| JP42009594B1 | ||||
| JP8333351A |
Foreign References:
| WO2000032566A1 |