常压升温下油煤浆表观黏度变化的研究

Apparent viscosity changes of oil-coal slurry during heating at atmosphere

为探讨煤直接液化工艺中油煤浆表观黏度随温度升高的变化规律,利用高温黏度计测定了煤浆体系的黏度,考察了溶剂、煤浆浓度、煤中含水量和不同显微组分等因素以及剪切速率、配浆温度、溶胀作用等对煤浆黏度-温度特性的影响。研究结果表明,低温下影响煤浆黏度变化的主要因素是溶剂本身的性质,煤浆的表观黏度随温度升高而降低;随温度继续升高在较宽温度范围内黏度变化不大,这是由溶剂性质以及煤在溶剂中的溶胀行为共同作用的结果;当温度达到约220℃后继续升高温度溶胀作用逐渐占优势,从而导致煤浆体系的表观黏度逐渐增大。

The changes of apparent viscosity of coaloil slurries with temperature during direct coal liquefaction were studied.Several factors influencing the viscosity of coal slurries were discussed,which include solvent properties,coal concentrations,moisture content,macerals of coal,shear rate,temperature,swelling behavior,etc.The apparent viscosity of coal slurries was measured using a high-temperature viscometer.The results show that the solvent property is the main influencing factor at low temperature,and the apparent viscosity decreases with increasing temperature.Solvent properties and swelling behavior work together for the viscosity of slurries at medium temperature,leaving the apparent viscosity invariable.Swelling behavior becomes the main influencing factor at high temperature,and viscosity of slurries increases with increasing temperature.