Effects of dispersants on preparing coal pitch water slurry

Abstract

<span style="font-size:11.0pt;font-family: " times="" new="" roman";mso-fareast-font-family:simsun;mso-bidi-font-family:mangal;="" letter-spacing:-.2pt;mso-ansi-language:en-gb;mso-fareast-language:en-us;="" mso-bidi-language:hi"="" lang="EN-GB">The coal pitch water slurry(CPWS) has been prepared with solutions of dispersants and medium temperature coal tar pitch powder corresponded with “bipeak trifurcated distribution” made by cryogenic grinding technology. The influences of HDBAC and Octadearyl dimethyl ammonium chloride on slurry ability, rheological behavior and stability of the CPWS have been investigated. Moreover, wetting, adsorption and the Zeta potential of aqueous solutions of dispersants on coal tar pitch's surface have also been discussed. The results show that HDBAC and STAC are both suitable to prepare the CPWS, and HDBAC is the better one. Apparent viscosity of the CPWS increases with the growing of slurry concentration when surfactant dosage remain unchanged, and the slurry concentration of CPWS prepared by HDBAC and STAC can reach 70% at most. The apparent viscosity declines when shear rate grows, so apparently, the CPWS is a pseudo plastic liquid and has a better rheological behavior. The stability becomes weaker with the passage of time. The adsorption of dispersants and Zeta potential on coal tar pitch increase with the growing of solution concentration. The contact angle of solution on coal tar pitch surface declines when dispersants added, which is helpful to build a stable diverse system. </span>