减压渣油热反应特性与原料组成的关联

RELATIONSHIP BETWEEN THERMAL REACTIVITY AND CHEMICAL COMPOSITION OF VACUUM RESIDUES

用大庆、大港、孤岛、胜利、华北、辽河、阿曼、阿拉伯轻等８种原油的减压渣油及其抽出率不同的脱油沥青共４０个油样，测定其元素组成、４组分组成、平均相对分子质量以及红外光谱，计算其平均结构参数。将上述油样在１００ｍｌ高压釜内于４１０℃下进行热转化。结果表明，原料的裂化转化率不仅取决于其氢碳比，还与其硫含量和氮含量有关；经多元非线性回归，得到相关性较好的关联式；原料的裂化转化率与其４组分组成也有较好的相关性。结果还表明，反应终了时体系的庚烷不溶物含量主要取决于原料的氢碳比，而油样的甲苯不溶物产率与反应终了时体系的沥青质与（芳香分＋胶质）的含量比有关，得到较好的经验关联式。

Thermal conversions of 40 feedstocks,including 8 residues(6 from Daqing,Dagang,Gudao,Shengli,Huabei and Liaohe crudes,2 from Oman and Arabian light crudes)and their deoiled asphalts with different yields by super critical fluid extraction were carried out in a 100ml autoclave at 410℃ and 1h.The elementary composition(C,H,S and N),SARA composition and average relative molecular mass of the feedstocks were determined,and their average structural parameters were elucidated.It is found that the cracking and condensation conversions of the feedstocks were well related with their H/C ratio,contents of sulfur(S%)and nitrogen(N%),average relative molecular mass(M),and SARA composition(mass percentages of saturates(Sat),aromatics(Ar),resin(Re)and asphaltene(Asp)).The results of non linear regression indicated that the factor K r defined by following two equations: K r=(H/C) 0 257 S 0 158 N 0 184 M -0 151 K r=Sat 0 026 Ar 0 008 Re 0 380 S 0 170 M -0 230 can characterize well the thermal cracking reactivity of the feedstocks at the above reaction conditions,and the factor K c defined by following two equations: K c=(H/C) -3 80 M 0 40 K c=(H/C) -3 80 (Re+Asp) 0 30 M 0 24 can also characterize well the thermal condensation reactivity of the feedstocks at the same mild reaction conditions.It is also found that the yield of toluene insolubles of the feedstocks was related linearly with the asphaltene/(resin+aromatics)ratio of the cracked residues,indicating that the formation of coke was not only the result of condensation reaction of asphaltene but also the result of phase separation of the colloidal system of the residue.