乙烯焦油对延迟焦化原料胶体稳定性及热解历程的影响研究

EFFECTS OF BLENDING ETHYLENE TAR ON COLLOIDAL STABILITY OF DELAYED COKER FEEDSTOCK AND PYROLYSIS PROCESS

采用n-d-M法、E-d-M法及四组分分析法,对现有延迟焦化原料(减压渣油、催化裂化油浆)及乙烯焦油进行了组成与性质分析,并通过测定原料油的电导率及热失重(包括TGA和DTA)分析,研究了乙烯焦油对延迟焦化原料胶体稳定性及热解过程的影响。结果表明,在现有的延迟焦化原料中掺炼乙烯焦油会导致原料中的饱和分含量降低、芳香分含量增加。在35℃条件下,延迟焦化原料的胶体稳定性参数随着乙烯焦油掺炼比的增加而增大,胶体稳定性在一定范围会得到改善。此外,乙烯焦油的掺入,会导致焦炭产量增加及生焦反应趋势提前,且产物中各馏分油收率会出现明显变化。说明乙烯焦油掺入后的热解过程及热解产物间并不是单纯的加和,而是一个相互影响的过程。

The n-d-M method,E-d-M method and hydrocarbon group(PONA)analysis method were used to analyze the composition and properties of the existing delayed coker feedstocks(vacuum residue,FCC slurry)and ethylene tar.The conductivity and thermal weight loss(including TGA and DTA)of feedstocks were measured,and the influence of blending ethylene tar on the stability and pyrolysis process of delayed coker feedstocks colloid was studied.The results showed that blending ethylene tar in the existing delayed coker feedstock would lead to a decrease in the saturation and an increase in the aromatic content of the feedstock.In the case at 35℃,the colloidal stability parameters of delayed coker increased with the increase of the ethylene tar blending ratio,and the colloidal stability was improved in a certain range.In addition,the mixing ethylene tar would lead to the coking reaction trend in advance and higher coke yield,and the yield of each distillate in the product would change significantly.It proves that the pyrolysis process and the pyrolysis products compositions are complicated after mixing ethylene tar.