System and method for increasing yield of p-xylene by utilizing carbon-rich natural gas

Abstract

The invention provides a system and a method for increasing the yield of p-xylene by using carbon-rich natural gas. The system comprises a methanol synthesis integrated unit, a methanol product separation unit, a methanol steam stripping unit, a toluene and methanol alkylation reaction unit, a three-phase separation unit, a toluene circulation unit and a xylene separation and purification unit which are connected in sequence, wherein an inlet of the methanol synthesis integrated unit is connected with a feeding pipeline, the feeding pipeline is divided into two branches, one branch is a carbon-rich natural gas pipeline, and the other branch is a feeding carbon-hydrogen ratio blending pipeline. According to the system and the method, natural gas loss and carbon dioxide emission reduction are avoided, and energy conservation and consumption reduction are achieved; and meanwhile, high-value utilization of the carbon-rich natural gas with high-concentration CO2 content is realized, and theyield of p-xylene is increased while carbon emission is reduced.

Description

technical field [0001] The invention belongs to the field of p-xylene production, and relates to a production method of p-xylene, in particular to a system and method for increasing the production of p-xylene by using carbon-rich natural gas. Background technique [0002] The extensive use of fossil fuels has led to an increase in the carbon dioxide content in the atmosphere year by year, and the greenhouse effect has become more and more serious. The reduction and rational use of carbon dioxide emissions is no longer a purely social responsibility. How to realize the high-value comprehensive utilization of carbon dioxide is imminent. Carbon-rich natural gas occupies an important position in China's unconventional natural gas. How to reduce carbon dioxide emissions and realize effective utilization is a difficult problem that needs to be overcome. [0003] Aromatics is an important raw material for the production of synthetic fibers, and the core of its industrial chain is m...

AI Technical Summary

Problems solved by technology

Natural gas CO is currently required under the delivery of commercial natural gas 2 The CO2 content in the South China Sea natural gas extracted from the South China Sea gas fields is not more than 3%. 2 The content is generally high, so part of the CO must be removed at sea 2 , it can be further used as natural gas. Most of the carbon dioxide removed at this stage is directly emitted, causing serious greenhouse gas emissions at the same time as the high separation cost; in addition, the separation of CO from natural gas 2 The process of decarbonization will inevitably increase energy consumption, and will also cause the loss of natural gas. Relevant research shows that in the process of natural gas decarbonization, the loss rate of natural gas is between 2.5% and 7%.

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