Treatment and recovery of larger particles of fine oxidized coal
US4222861A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 8, 1978 |
| Grant date | Sep 16, 1980 |
| Priority date | — |
| Expiry date | Jun 8, 1998 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB03D2203/08
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
This invention relates to a method and treating agent for increasing the yield of larger particles of fine oxidized coal where the particle size is 28.times.100 mesh and preferably 28.times.70 mesh and where said coal particles are concentrated by froth flotation. The method consists of utilizing as a promoter an alkali metal or ammonium polyacrylate. A preferred promoter is about 0.05-1.5 lbs of sodium polyacrylate latex per ton of dry coal (0.017-0.5 lb of dry sodium polyacrylate per ton of dry coal), having an average molecular weight of about 100,000, to 1,000,000 and more, with a preferred range of 1,000,000 or more. This preferred promoter or frothing aid for oxidized coal is a water-in-oil latex of sodium polyacrylate used with a water-in-oil emulsifier and preferably used with an alcohol-type frother. The latex may be utilized neat and self inverts with the assistance of an oil-in-water surfactant and the water in the system upon application to form an oil-in-water emulsion, or it may be used as a two part system with an activator (aqueous) to promote inversion. Additionally, the latex emulsion recovers larger particles in the size 100 mesh and greater and preferably in the…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.