Production equipment and process of p-xylene

Abstract

The invention discloses a production device and process of p-xylene. This production unit comprises xylene fractionation unit, adsorption separation unit and isomerization reaction unit; Described adsorption separation unit comprises adsorption separation tower, extract liquid tower, raffinate tower, finished product tower, finished product tower reboiler 1 and Finished product column reboiler II; the described isomerization reaction unit includes isomerization reaction rectification tower, clay tower, isomerization reaction heating furnace, heat exchanger II, heat exchanger III, heat exchanger V and compressor. The invention also provides a production process for p-xylene. The invention reduces the equipment investment, reduces the operating load of the xylene tower, saves the fuel gas consumption of the xylene reboiler, and simultaneously performs the isomerization reaction and the product separation to realize the coupled utilization of energy; optimize the heat exchange The network reduces the fuel gas consumption of the isomerization reaction heating furnace, greatly reduces energy consumption, and improves economic and social benefits.

Description

technical field [0001] The invention relates to a production device and process of p-xylene. Background technique [0002] P-xylene is one of the important basic organic raw materials in the petrochemical industry. It is mainly used to produce terephthalic acid (PTA) and dimethyl terephthalate (DMT). It is widely used in chemical fibers, synthetic resins, pesticides, and medicines. , plastics and other production areas. In 2017, the apparent consumption of p-xylene in my country will reach 2400×10 4 t, the production capacity of p-xylene unit reaches 816×10 4 t, accounting for about 20% of global production capacity, my country is already the world's largest producer of p-xylene. [0003] C 8 Aromatics include o-xylene, p-xylene, m-xylene and ethylbenzene four isomers, among which p-xylene has the largest market, so the industry usually prefers to increase the specific C 8 The production of para-xylene from aromatics feedstock sources even maximizes it. Due to their si...

AI Technical Summary

Problems solved by technology

In this process, the heat of the reboiler of the finished product tower is provided by the desorbent and the bottom liquid of the xylene tower, which consumes a lot of energy, and the isomerized product is removed by the deheptanizer. 7 Most of the light hydrocarbons are recycled back to the xylene tower, increasing the operating load of the xylene tower and increasing the fuel consumption of the xylene reboiler

In addition, all isomerized products must be cooled. After the hydrogen gas that has not participated in the reaction is separated, the cooling load is relatively large; the material after the hydrogen gas is separated needs to be reheated, and it enters the deheptanizer for further separation. The material is cooled first and then heated. problem, resulting in a waste of energy

Images