The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 31, 2017
Filed:
Sep. 17, 2009
Hongke Zhang, Zhejiang, CN;
Weiqi Hua, Zhejiang, CN;
Xiaogao Liu, Zhejiang, CN;
Zhenhua Zhao, Zhejiang, CN;
Shuchang Sun, Zhejiang, CN;
Jiansheng Ding, Zhejiang, CN;
Jianfeng Chen, Beijing, CN;
Pengyuan Zhang, Beijing, CN;
Haikui Zou, Beijing, CN;
Guangwen Chu, Beijing, CN;
Limin Xu, Beijing, CN;
Hongke Zhang, Zhejiang, CN;
Weiqi Hua, Zhejiang, CN;
Xiaogao Liu, Zhejiang, CN;
Zhenhua Zhao, Zhejiang, CN;
Shuchang Sun, Zhejiang, CN;
Jiansheng Ding, Zhejiang, CN;
Jianfeng Chen, Beijing, CN;
Pengyuan Zhang, Beijing, CN;
Haikui Zou, Beijing, CN;
Guangwen Chu, Beijing, CN;
Limin Xu, Beijing, CN;
WANHUA CHEMICAL (NINGBO) CO., LTD., Zhejiang, CN;
Abstract
The invention relates to a method of circular use of waste brine produced in the manufacture process of MDI, comprising the following steps: (1) the waste brine produced in the manufacture process of MDI is subjected to a high-gravity extraction and then to a column extraction, wherein said waste brine contains aniline, diaminodiphenylmethane and polyamine; (2) the waste brine from step (1) is transmitted to a stripping tower for steam stripping; (3) the waste brine from the stripping tower of step (2) and a chemical oxidant are transmitted to an oxidation reactor to which air is blown for aeration; (4) the waste brine after the treatment of step (3) is transmitted to an absorption tower for absorption. The invention makes the salt water have TOC of less than 8 ppm and TN of less than 2.5 ppm and achieves regeneration of resources in the waste brine such as sodium chloride and water and the like for circular use.