C4 two-stage hydrogenation device and process in catalytic thermal cracking to ethylene

Abstract

A C4 two-stage hydrogenation device in catalytic thermal cracking to ethylene, which includes a hydrogenation reactor, a mixer and a feed heater, and its technical points are: the first-stage hydrogenation reactor and the second-stage hydrogenation reactor The inlet ends are connected to feed mixers, the outlet of the first-stage hydrogenation reactor is connected to the reflux tank through the discharge cooler, the outlet of the reflux tank is connected to the inlet of the reflux pump, and the outlet of the reflux pump is connected to the feed heater and the second-stage feed mixer in parallel. The material heater is connected to the first-stage feed mixer, and the C4 material feed pipe is connected in parallel on the pipeline between the feed heater and the first-stage feed mixer, and on the pipeline between the reflux pump and the second-stage feed mixer. The present invention adopts two-stage selective hydrogenation, which avoids serious coking in the first-stage reactor caused by deep hydrogenation of 1,3-butadiene, and reduces the operation cycle of the device and the service life of the catalyst. In addition, due to the stronger adaptability to raw materials, it is not necessary to separate light and heavy carbon four, and the mixed carbon four can be directly hydrogenated, which improves the utilization rate of raw materials.

Description

technical field [0001] The invention relates to the field of petrochemical technology, in particular to a C4 two-stage hydrogenation device and process for catalytic thermal cracking ethylene production by effectively controlling the temperature rise of the reaction bed and the content of butadiene. Background technique [0002] As we all know, the catalytic thermal cracking ethylene CPP unit is a new technology developed on the basis of the catalytic cracking DCC process. Through further improvement of the existing process and catalyst, the target product is changed from propylene to co-production of ethylene and propylene. The by-product light carbon four produced by it will be used as the feed for the methyl tert-butyl ether MTBE unit after a stage of catalytic selective hydrogenation. After the technical transformation, a naphtha cracking furnace was newly added, and the cracked gas produced together with the reaction oil gas of the original reaction system was used as t...

AI Technical Summary

Problems solved by technology

It can be seen that after the original one-stage catalytic selective hydrogenation, the feed requirements of the methyl tert-butyl ether MTBE unit cannot be met. Therefore, it is necessary to research and develop a new hydrogenation process to meet the production needs of the MTBE unit.

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