Effect of Preparing Condition on Apparent Viscosity of Coal Oil Slurry at Different. Temperature and Atmospheric Pressure

摘要

Coal oil slurry, or coal solvent paste, one of emblematical solid liquid two phase flow, is a crucial important constituent of the feedstock for direct coal liquefaction, and its viscous property plays prominent technical rule for manageable and pumpable mixture preparation. The effects of preparation conditions, such as solvent, coal particle size, and concentration of coal particle on apparent viscosity of Chinese lignite (from Erdos, Inner Mongolia of China) oil slurry were investigated at temperature range from 303K to 623K and ambient pressure. Experimental investigations revealed that the pastes are non-Newtonian fluid. The viscosity of suspension possesses negative correlation with coal particle size distribution (CPSD). However, the apparent viscosity of suspending system presents complicated change at range of 353K to 623K. It decreases at range of 303K to 353~433K, and keeps, approximatively, constant at the range of 353~433K to 573K, and then, increases at range of 573K to 623K for different slurries. Notwithstanding the diversity, the viscosity of the mixtures can be predicted with a series of 6th-order polynomial models in terms of temperature.