Circulation methanol preparation system

Abstract

The present invention relates to a methanol production system with circulation method, which includes No. 1 absorption tower and No. 2 absorption tower; it is characterized in that the tail gas outlet of No. 2 absorption tower is connected with a tail gas recycling device, and the tail gas recycling device includes hydrogen A separator and a gas-liquid separator, the hydrogen filter is connected to the gas-liquid separator, the exhaust end of the gas-liquid separator is connected to a gas compressor through a circulating gas pipe, and the gas compressor is connected to the gas-liquid separator through a compressed gas pipeline. methanol mixer. The invention can make full use of the heat in the tail gas, cooperate with strict control of various parameters, can greatly improve the methanol conversion rate of the invention, the purity can reach 40-50%, and the energy consumption is relatively small.

Description

technical field [0001] The invention belongs to the technical field of formaldehyde preparation systems, and in particular relates to a circulation method methanol preparation system. Background technique [0002] Formaldehyde is a colorless aqueous solution or gas with a pungent odor and is miscible with water, ethanol, acetone and other organic solvents in any proportion. The liquid tends to become turbid when it is stored for a long time when it is cold, and it will form a paraformaldehyde precipitate at a low temperature. When evaporating, a part of formaldehyde escapes but most of it turns into paraformaldehyde. This product is a strong reducing agent, and its reducibility is stronger when it is slightly alkaline. It can be slowly oxidized to formic acid in air. [0003] Formaldehyde has a wide range of uses, and about 65% of its consumption is used to produce formaldehyde resins, mainly urea-formaldehyde resins (adhesives, aminoplasts), phenolic resins (adhesives, p...

AI Technical Summary

Problems solved by technology

[0005] The formaldehyde plant using the silver catalyst process generally has a large production capacity and a high conversion rate of methanol, but the purity is low, generally 20-30%, and the heat energy waste in the production is serious, the methanol consumption is low, no distillation device is needed, and it can be produced High concentration of formaldehyde, low alcohol content in formaldehyde products, long service life of catalyst, large one-time investment and high power consumption

The silver method has simple process, low investment, strong adjustment ability, and less formic acid content in the product, but the methanol conversion rate is low, the unit consumption is high, the catalyst life is short, the purity of methanol is high, and the methanol content in the finished formaldehyde product is high, so it can only produce low concentration. Formaldehyde, and the tail gas treatment is generally only treated by incineration to generate steam for use. This tail gas treatment method wastes energy and is not conducive to the production of higher concentrations of formaldehyde

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