| 摘要 |
<p>A method and treating agent for increasing the yield of deep mined coal mined from a site 100 feet or more below the surface where the particles in the coal are concentrated by froth flotation. This method consists of utilizing as a promoter or frothing aid 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. The preferred promoter or frothing aid for deep mined coal is a water-in-oil latex of sodium polyacrylate 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 (or activator) 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. The latex emulsion has demonstrated superiority as a flotation promoter for deep mined coal over the dry polymer and exhibits synergism over the dry polymer and over the components of the latex emulsion including a paraffin solvent, a hydrophobic emulsifier such as sorbitan monooleate, a solvent such as Espesol 3-E (Charter; an aromatic blend) and stabllizers such as polyisobutylene and aluminum tristearate.</p> |
