CO.sub.2 Pretreatment prevents calcium carbonate formation
US4206033A · kind A · utility
9Cited by
6References
7Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 14, 1978 |
| Grant date | Jun 3, 1980 |
| Priority date | — |
| Expiry date | Aug 14, 1998 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S208/951
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Scale formation during the liquefaction of lower ranking coals and similar carbonaceous materials is significantly reduced and/or prevented by pretreatment with carbon dioxide. The carbon dioxide pretreatment is believed to convert the scale-forming components to the corresponding carbonate prior to liquefaction. The pretreatment is accomplished at a total pressure within the range from about 14 to about 68 atmospheres and a carbon dioxide partial pressure within the range from about 14 to about 34 atmospheres. Temperature during pretreatment will generally be within the range from about 100.degree. to about 200.degree. C.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.