Effect of oxygen-containing functional groups and pore structure characteristics of coal on the slurryability of coal wastewater slurry

Abstract The physical and chemical characteristic of coal have an important influence on the slurryability of coal wastewater slurry. In this paper, eight different coals are used to make coal wastewater slurry, and the effects of oxygen containing functional groups and pore structure characteristics of different coal samples on the slurryability are analyzed. Results show that (a) Coal with more oxygen-containing functional groups on surface have stronger hydrophilicity, higher surface activity and have stronger adsorption capacity for water molecules, this will lead to the reduction of free water and the increase of viscosity of the slurry. (b) Coal with larger BET specific surface area and pore volume and smaller average pore diameter have the stronger ability to adsorb and store water in coal wastewater slurry, thus the concentration of coal wastewater slurry prepared from these coal is low. The conclusion of this paper can provide reference for coal selection in the preparation of coal wastewater slurry.