Abstract

ALEJO, Bonifacio  and  BARRIENTOS, Arturo. Effect of the parameters in the stability of the coal suspensions in aqueous environment. Rev. Met. UTO [online]. 2011, n.30, pp. 34-42. ISSN 2078-5593.

The rheological properties of the concentrated solutions of bituminous coal were determined in an aqueous environment with a Mooney-Ewart viscometer. The studied suspensions have values of yield stress like a pseudo-plastic. The particles size is 22-100 micrometers, according to the Rossin Rammler natural distribution. Theformation of floccules or aggregates in the isoelectric point of coal (pH = 7,0) creates the highest viscosity values for the studied concentrations. The suspension (M = 0,35) act like a Newtonian fluid when the pH value is 10. The regions, which have good rheological stability of the coal suspensions, are out of the isoelectric point. The coal isoelectric point was determined trough viscosity measurements based on pH for the studied concentrations.

Keywords : coal; pH; isoelectric point; rheology; stability.