黏土矿物对超临界水中稠油改质的影响

Effect of Clay Minerals on the Supercritical Water Upgrading of Heavy Oil

本研究对稠油在超临界水环境中的提质过程以及常见黏土矿物(包括蒙脱石、高岭土、伊利石和绿泥石)对提质过程的影响规律进行了探究。研究主要包括了黏土矿物对稠油提质过程的主要产物(气、油、焦)的产量和成分组成的影响规律,揭示了四种常见黏土矿物对稠油超临界水改质过程产物的影响规律,并分析了其影响机制。研究发现,绿泥石和蒙脱石对稠油改质过程的产量方面产生了正向的催化效果,能够在抑制结焦的同时使产油产气量提升或保持原有水平.而伊利石和高岭石则展现出了双向催化效果,即同时促进了油向气和焦的转化。在气体组分方面,蒙脱石的存在提高了气体产量的同时增加了气体产物中二氧化碳的比例,而伊利石、绿泥石和高岭石的催化作用为提高气体产率而不能改变气体成分组成。在产油方面,绿泥石的存在使油的产量上升,而其余三种黏土矿物的存在使油的产量出现不同程度的下降。在产油组分方面,黏土矿物能够催化稠油中的重质组分裂解为轻质组分。在结焦方面,黏土矿物对焦的产量和特性有明显的影响。蒙脱石和绿泥使结焦量出现明显下降。并且,黏土矿物均能够使焦的DTG峰值温度出现明显下降,从而使焦具有更好的氧化活性。

The supercritical water upgrading(SCWU)of heavy oil and influence pattern of clay minerals(including montmorillonite,kaolinite,illite,and chlorite)on the SCWU process were in-vestigated through experiments.The study mainly covered the influence law of clay minerals on the yield and composition of the main products(gas,oil,and coke).The influence of clay minerals on the products of the heavy oil SCWU process was summarized,and their influence mechanisms were analyzed.Chlorite and montmorillonite were found to have a positive catalytic effect on the yield of SCWU process,which could increase or maintain the oil and gas production while inhibiting coking.Illite and kaolinite showed a two-way catalytic effect,i.e.,promoted the conversion of oil to gas and coke at the same time.In terms of gas products,the presence of montmorillonite increased the gas yield while increasing the proportion of carbon dioxide in the gas products.In contrast,the catalytic effect of illite,chlorite and kaolinite was to increase the gas yield without changing the gas composition.In terms of oil products,the presence of chlorite increases oil production,while the presence of the remaining three clay minerals decreases oil production.Also,clay minerals were able to catalyze the cracking of heavy components in heavy oil to light components.In terms of coke products,clay minerals showed a significant effect on the coke yield and characteristics.Montmo-rillonite and chlorite caused a significant decrease in the coke yield.Moreover,clay minerals were able to cause a significant decrease in the DTG peak temperature of coke,which resulted in a better oxidation of coke.