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:
Mar. 04, 1997
Filed:
Sep. 05, 1995
Werner Pohl, Essen, DE;
Johannes Menzel, Oberhausen, DE;
Krupp Koppers GmbH, Essen, DE;
Abstract
In the process for purifying an aqueous MDEA-solution the formate content of the MDEA-solution circulated in a main stream between the absorber and desorber of a hydrogen sulfide wash unit for gas produced by gasification of a carbonaceous material, e.g. coal, is measured. A partial stream of MDEA-solution is withdrawn from the main stream, passed over an ion exchange medium which removes some formate present to form a partially purified partial stream and subsequently the purified partial stream is returned to the main stream. The amount of the withdrawal from the main stream is controlled so that the formate content of the main stream is maintained between 10 and 30 g/l. Only from 0.5 to 0.08% by volume need be withdrawn from the main stream to form the partial stream. The ion exchange medium can be regenerated with a hydroxide-containing solution, which is subsequently fed to an ammonia separator column of a hydrogen sulfide wash apparatus.