Technology Of Coal-water Slurry Particle Size Gradation (datong Coal)

After the western countries which used fossil oil as their main resources were shocked heavily by the oil crisis in 1970's, they kept on searching substitutes. Coal is a kind of important resources from old day on which could burn directly. But as coal was not so convenient as fossil oil and natural gas in burnings storage and transportation and it's a pollutant, it's urgent to look after a flowing fuel. The technology of CWS (coa] water slurry) was invented to overcome all the shortages mentioned above.After the industrial analysis and elemental analysis, we found that Datong coal contains low quantity of ash and sulfer. We also found that Datong coal contains more phenolic hydroxyl and less carboxyl. The slurry ability and stability of [atong coal is in the middle class. Fixing the amount of surfactant in the dry coal, we made slurry using coarse coal (>75μm) and finer coal (<75μm <50μm <38μMake slurry at different ratios using the coarser coal andthe finer coal and measure the weight contents viscosity and stability, we found same rules. The optimal values were gained at the ratios of 70:30?5:15.Distribute the coal into 4 particle sizes and make slurry and measure the weight content viscosity and stability, we found that there were several PSDs (particle size distributior.) which could achieve industrial standards. In all of the PSDs, 6:2:2:0 is optimal.We made slurry according to Alfred formula and found thg.t the slurry was stable and can't reach industrial standards. It"s thought that the coarer coal in the Alfred formula is more than in the PSD of 6:2:2:0.Analyse the PSDs using laser particle analyzer, we found that much of finer coal reunite in slurry.