Enhancement of rheological behavior of indian high ash coal-water suspension by using microwave pretreatment

In this paper, rheological characteristics of coal-water slurries (CWS) by using microwave pretreatment have been presented. Detailed experimental investigations were carried out for two high ash Indian coals with 38 and 32% ash content. Experiments were conducted at the 900 W power level and various exposure times of 30, 60, 90, and 120 s. Before and after treatment, the samples were ground for rheological characteristic of CWS in an online Bohlin viscometer. All slurries were found to exhibit pseudoplastic characteristics and results indicate that the rheological properties of microwave-treated coal are better than untreated coal. The density of microwave-treated coal is less than that of untreated coal after grinding. A factorial plan was used, and empirical equations were obtained and found to be encouraging and highly significant. © 2010 American Chemical Society.