柱色谱分离法预测塔河常压渣油脱沥青油杂质含量的研究

塔河原油是一种沥青质含量高、残炭高、金属含量高、酸值高的重质原油,为避免传统加工过程中的高温腐蚀和塔河渣油进催化裂化装置的高残炭、高金属含量等问题,考虑将塔河原油经常压闪蒸后的渣油直接作为溶剂脱沥青的原料。采用挂片失重试验对塔河原油的腐蚀性进行了研究,同时对适宜闪蒸温度下的常压闪蒸渣油进行了六组分分离,并对各组分的化学性质和结构参数进行了分析。结果表明:53.89%的硫、86.97%的氮、98%以上的镍、钒金属存在于胶质和沥青质组分中;随着组分加重,芳碳率fA增加,H/C原子比、环烷碳分率fN和芳香环系缩合度参数HAU/CA减小;将塔河常压闪蒸渣油在不同柱色谱馏出油收率下的杂质脱除率曲线与溶剂脱沥青中试结果对比发现,两者有较好的相似度,表明采用柱色谱分离方法可以在一定程度上来预测溶剂脱沥青过程不同脱沥青油收率时的杂质含量,可指导塔河常压闪蒸渣油溶剂脱沥青过程的操作。

PREDICTION OF IMPUITY CONTENT IN DEASPHALTED OIL OF TAHE ATMOSPHERIC RESIDUE BY COLUMN CHROMATOGRAPHY

Tahe crude oil is a heavy crude oil with high content of asphaltene, carbon residue, metal and high acid value. The corrosion of Tahe crude oil was investigated by the weight loss of hanging slice method. Tahe atmospheric residue after flashing was directly used as the solvent deasphalting raw material in this work. Tahe atmospheric residue was separated into six fractions and the structure parameters of the six fractions were calculated by the modified Brown-Ladner method. The results indicate that 53.89% of sulfur, 86.97% of nitrogen and more than 98% of Ni and V metals exist in resin and asphaltene. With the deterioration of the fractions, fA increases, while H/C, fN and HAU/CA decrease. There is a good correlation between the impurity removal rate under different chromatographic effluent yield and the results of solvent deasphalting process in pilot plant, indicating that the chromatographic separation method can be used to predict the impurity content of deasphalted oil with different yield of deasphalting process and to guide the solvent deasphalting process.