Research On The Cracking Performance Of The Feed In Ethylene Plant Of DPC

Ethylene plant,which is the basic and leading industry,plays a pivotal role in the petrochemical industry.But in recent years,in the ethylene industry field,cracking-feed materials are increasingly in shortage.In order to expand the source of cracking-feed materials and diversify them,a variety of research work was carried on in major chemical companies.Discussion from the principle of cracking reaction,reaction parameters,the cracking-feed evaluation method,present situation of domestic cracking-feed and the ptimization of cracking-feed structure aspects.By using a small simulation cracking furnace,the single cracking and co-cracking experiments were carried out on five kinds of craking-feeds,which includs hydrogenated tail oil,naphtha and light diesel,light hydrocarbon and aromatics raffinate oil.The suitable reaction conditions were determined and the product distribution and operating condition data were obtained.According to the analysis of experimental data in this paper,the target olefins yield is in descending order of “hydrocarbon> naphtha> hydrogenation tail oil> naphtha> aromatics raffinate oil”;With the increase of the mixing ratio of light diesel in the hydrogenated tail oil,the olefins yield of the cracking reaction decreases,which is lower than that of the hydrogenated tail oil,and which is higher than that of the light diesel;With the increase of the mixing ratio of hydrocarbons in the naphtha,the olefins yield of the cracking reaction increases;The increase of cracking temperature has a greater significant effect on the yield of ethylene than that on the yield of other olefins in the co-cracking mode of hydrocarbonnaphtha;The yield of olefins in the co-cracking mode of naphtha-hydrocarbon-aromatic raffinate oil is lower than that in the single mode;Compared with the co-cracking mode of naphtha-hydrocarbon,adding aromatics raffinate oil reduces the yield of olefins.In addition,this article creatively put forward the conclusion that two crossover temperatures T1,T2 exists and divide the cracking temperature into three intervals.In different intervals,the olefins yield has different properties.