Cleaning processes using cleaners exhibiting cloud point behavior
US5820690A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 7, 1995 |
| Grant date | Oct 13, 1998 |
| Priority date | — |
| Expiry date | Jun 7, 2015 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB08B3/10
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A cleaning process to remove soil using cleaners exhibiting cloud point behavior (i.e., have a cloud point) and/or in which the cleaner can be recycled is disclosed. The cleaning mixture can be an aqueous cleaning mixture. The temperature can be adjusted so that the cleaning mixture is contacted with the object to be cleaned at a temperature at or above the cloud point temperature, and the temperature and/or composition of spent cleaning mixture can be adjusted so that it is processed to form a soil-enriched stream and a soil-depleted stream while it is below its cloud point temperature. Processing to form the soil-enriched and soil-depleted streams can involve adjusting the system so that at steady state ##EQU1## where C.sub.Washer is the concentration of cleaner in the spent cleaning mixture and C.sub.Washer Target is the desired concentration of cleaner in the cleaning mixture prior to contacting the object to be cleaned. Desirably a hyperhydrophilic membrane is used in a filtration process to form the soil-enriched and soil-depleted streams from the spent cleaning solution.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.