Method of removing gangue materials from coal
US4146366A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 21, 1977 |
| Grant date | Mar 27, 1979 |
| Priority date | — |
| Expiry date | Nov 21, 1997 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB03B9/005
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A method of removing gangue materials from coal characterized by the steps of comminuting and sizing all of the material to have most particles of a size smaller than one hundred microns; slurrying in an alcohol containing 1 to 4 carbon atoms; thereafter separating by settling velocity separation into an overflow stream containing most of the valuable coal products for storage as a fuel or the like and an underflow containing the gangue materials with some larger sized coal particles; thereafter diluting the underflow with alcohol and separating by settling velocity separation or the like into an overflow stream containing the coal for storage and an underflow containing mostly gangue material with some coal particles; separating the alcohol from the gangue materials and returning the alcohol to the process. The gangue materials can be employed as a fuel if they contain enough of the entrained coal particles. Preferably, the comminution to effect mostly particles smaller than 100 microns is effected by a multi-step process including crushing and screening to drying size; drying; and separating into top and bottom streams, the hot latter being sent to a thermal-chemical reactor empl…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.