Problems in aromatic extraction
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I would appreciate some guidance: Can the aromatic hydrocarbon extraction–extractive distillation technique be used for triphenyl extraction? What are the technical bottlenecks? Are there any relevant operational records domestically and internationally? Which is more suitable for aromatic extraction units downstream of large-scale continuous reforming – the technology developed by the Institute of Petrology or GTC’s extraction distillation technology?
Both liquid-liquid extraction and distillation extraction now use triphenyl.
Extractive distillation can be used to extract triphenyl, with the technical challenges lying in the recovery rate of benzene and the purity of xylene. Currently, in China, the triphenyl extraction of pyrolysis oil from Dushanzi, Xinjiang is in operation, using a process package provided by GTC Company. At present, most customers who require triphenyl extraction use hydroprocessed cracked gasoline as raw material. Reformate usually contains a high level of C8 aromatics (especially in continuous reforming), and thus triphenyl extraction is not necessary; the C8 component can be distilled out and fed into the PX unit. The largest aromatic extraction plants in China are all designed by GTC: Shenghong’s plant has a capacity of 2 million tons per year, while Hengli’s plant has a capacity of 1.5 million tons per year – these are essentially the largest such plants in the world. Hengli will drive quickly to see how his skill level holds up under pressure.
Thank you for the reply: handshake
The technical bottleneck is likely the enrichment of heavy hydrocarbons in the solvent, which significantly reduces the effectiveness of the lean solvent.
Hello, is there any difference in composition between ethylene cracking hydrogenated gasoline and reformed gasoline? Aromatic compound content?
Does a low benzene recovery rate mean a high benzene content in the raffinate oil? Can it be adjusted and optimized in terms of operation? What does it mean when the purity of xylene is low?
Does it refer to poor separation performance in the solvent recovery tower? Does the poor solvent band at the bottom of the tower contain C8 components?
What does heavy hydrocarbon in a solvent refer to? The C8+ component? Is the solvent recovery tower not stripping thoroughly? Can adding a water wash and elution column achieve complete removal?
Yes, it is mainly the accumulation of heavy aromatics. There are currently patents for extracting a stream of solvent and washing it with light oil, which can help alleviate the accumulation of heavy hydrocarbons in the lean solvent.