High-efficiency heat-integrated moving-bed methanol-to-hydrocarbon process

Abstract

The invention relates to an efficient heat-integrated method for preparing hydrocarbon from methanol by adopting a moving bed. The method comprises a hydrocarbon synthesis step, a separation step and an after-treatment step, wherein in the hydrocarbon synthesis step, two reactors which are connected with each other in series are adopted; reaction products of a plurality of reactors are utilized to perform heat-exchange heating on reaction raw materials and low-carbon-hydrogen containing recycle gas produced in the separation step, so that the recycle gas is returned to different feeding positions of the hydrocarbon synthesis step as quenching gas or raw material supplementing gas of the hydrocarbon synthesis step; the raw material methanol is utilized to perform scrubbing-absorption on C1-C4 light components generated in the separation step, and returned for being fed and converted, so that the methanol is transformed into high value-added stable light hydrocarbon comprising mixed aromatic hydrocarbons. According to the method, the refining control on a reaction process is improved through inter-stage heat exchange of reaction prdocuts, so that the materials are effectively utilized and thermally integrated among processing processes, and the environmental pollution is reduced while the product yield is increased and the energy consumption is reduced.

Description

technical field [0001] The invention relates to a process for producing hydrocarbons from methanol using a moving bed, and the heat of reaction products in the process can be efficiently circulated and utilized. Background technique [0002] BTX aromatics (Benzene, Toluene, Xylene) are important basic raw materials in petrochemical industry, among which p-xylene (PX) has the greatest demand. With the rapid expansion of domestic PX downstream PTA and polyester production capacity, the supply of PX in the market is seriously insufficient. By 2013, my country's external dependence on p-xylene has reached 55.3%, and the gap between supply and demand has further increased. The PX project produced by the traditional process is difficult to construct, has a high production technology threshold, and requires a large investment, and is more limited by the raw material naphtha resources. At present, the shortage of oil resources in my country and the increase in consumption demand ha...

AI Technical Summary

Problems solved by technology

[0007] (1) The degree of back-mixing of the catalyst in the fluidized bed is relatively heavy, and excessive local reaction can easily lead to coking; (2) The turbulence in the fluidized bed is severe, the wear is serious, and the expensive catalyst is easily damaged and then runs out, resulting in economical problems. (3) The residence time distribution in the fluidized bed is wide, which easily leads to a wide distribution of products and a decrease in the yield of the target product; (4) Temperature and pressure fluctuations will affect the efficiency of the gas-solid separation system, thereby affecting the subsequent Fractional distillation system; (5) For the reaction system with low coke formation rate, it is difficult to maintain the heat balance of the reaction regeneration system of the fluidized bed

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