Loading patent…
AssigneeAB Scaniainventor
InventorsOlle L. Siwersson, Arne E. Wall, Jan A. T. Loodberg
Estimating the term…
A composition consisting of carbon powder, water and a dispersing agent. The particle size of the carbon powder is less than 100 .mu.m, preferably less than 40 .mu.m. The composition is obtained by preparing a mixture of about 1-20% by weight, preferably about 10% by weight, of carbonaceous powder, water and 0.02-4% by weight of dispersing agent. The dispersing agent is selected preferably from polyelectrolytes, such as alkali metal and ammonium salts of polycarboxylic acids, and polyphosphates. These substances possess the property of charging the powder particles of carbon and the impurity particles in a different degree. This different charging is utilized to separate impurity particles from carbon particles, whereupon the purified composition is suitably dehydrated to attain an increased carbon powder concentration of, for instance, 50-80% by weight.
A stabilized coal slurry comprising pulverized and purified coal, water and a dispersing agent, said dispersing agent by selective absorption having produced different charging of particles of coal and particles of other substances to obtain purified coal and maintain the stability of the slurry.
A method for preparing from a carbonaceous starting material which, in addition to coal, also includes impurities, a stabilized coal slurry containing the coal in pulverized purified form, as well as water and a dispersing agent, wherein the carbonaceous starting material is mixed with water, pulverized and, in connection with or subsequent to pulverization, supplied with a dispersing agent by selective adsorption produces different charging of coal particles and impurity particles, and wherein this different charging is utilized in order to separate the coal from the impurities and to stabilize the coal slurry.
Dependencies are inferred from the claim text.