Viscosity-temperature characteristics of coal-oil slurry in coal / oil co-processing
ZHANG Yanjun,SHU Geping,GAO Shansong
煤油共炼技术将煤化工技术与劣质重油加工技术耦合,是煤与劣质重油清洁高效利用的重要途径,油煤浆黏温特性是影响规模化制浆、输送、加压、预热设计和生产操作的关键因素。以塔河重油、煤焦油和低阶煤为研究对象,利用热重分析仪、傅里叶红外分析仪、表面孔隙结构分析仪及高温黏度计等,分析了油煤浆浓度、溶剂性质、溶胀时间及煤粉孔隙结构对油煤浆黏度的影响,研究了制浆过程和升温预热过程中油煤浆黏温特性的变化规律。结果表明,制浆过程中质量分数和重质油溶剂性质是影响油煤浆黏度的主要因素;当质量分数大于35%时,油煤浆黏度显著增大;相同条件下,塔河重油煤浆黏度大于煤焦油重油煤浆。随溶胀时间的增加,重质油煤浆黏度整体呈增大趋势;溶胀12 h以后,油煤浆黏度均快速增大,且塔河重油配制的油煤浆黏度增加更快;溶胀作用之后的煤粉颗粒表面形成新的孔隙结构,产生了大量大孔和部分微孔,导致油煤浆黏度增加;油煤浆制备过程中重质油发生脱氢、吸氧缩合反应而导致性质变化也是影响油煤浆黏度的重要因素。升温预热过程,随着温度升高,油煤浆黏度迅速降低;且浓度越高,黏度越大;当温度超过140℃时,黏度均降至较低值;当温度超过240 ℃时,开始出现黏度反增现象,浓度越高煤浆黏度出现反弹的温度越低,反弹幅度越大。
Coal / oil co-processing technology is an important way for the clean and efficient utilization of coal and inferior heavy oil by coupling coal chemical technology with inferior heavy oil processing technology. Viscosi-ty-temperature characteristics of coal-oil slurry are the key factors affecting the design and operation of large-scale pulping,transportation,pressurization and preheating. Taking Tahe heavy oil,coal tar heavy oil and low-rank coal as research objects,the effects of concentration of coal-oil slurry,solvent properties,swelling time and pore structure of pulverized coal on the viscosity of coal-oil slurry were analyzed by thermogravimetric analyzer,Fourier infrared analyzer,surface pore structure analyzer and high temperature viscometer. The variation law of viscous-temperature characteristics of coal-oil slurry during slurry preparation and preheating was studied. The results showed that the concentration and solvent properties of heavy oil were the main factors affecting the vis-cosity of coal-oil slurry. When the concentration was more than 35% ,the viscosity of coal-oil slurry increased significantly. Under the same conditions,the viscosity of Tahe heavy oil-coal slurry was higher than that of heavy coal-tar-coal slurry. With the increase of swelling time,the viscosity of heavy oil-coal slurry increased as a whole. After 12 hours of swelling,the viscosity of two kinds of heavy oil-coal slurry increased rapidly,and the viscosity of Tahe heavy oil-coal slurry increased faster. After swelling,a new pore structure was formed on the surface of pulverized coal particles,which resulted in a large number of macropores and some micropores,resulting in an increase in the viscosity of coal-oil slurry. Dehydrogenation and oxygen absorption condensation of heavy oil during the preparation of coal-oil slurry were also important factors affecting the viscosity of coal-oil slurry. In the preheating process,the viscosity decreased rapidly with the increase of temperature,and the higher the concentra-tion,the higher the viscosity. When the temperature exceeded 140 ℃ ,the viscosity decreased to a lower value. When the temperature exceeded 240 ℃ ,the viscous rebound phenomenon began to appear. Besides,the higher the concentration,the lower the temperature at which the viscosity of coal-oil slurry rebounded,and the larger the rebounded range.
coal / oil co-processing; coal-oil slurry; viscosity-temperature characteristics; coal-oil slurry preparation; preheating process
主办单位:煤炭科学研究总院有限公司 中国煤炭学会学术期刊工作委员会