Formaldehyde absorbing tower dealcoholizing technology

Abstract

The invention discloses a formaldehyde absorbing tower dealcoholizing technology belonging to the chemical processing field. The method comprises: mixing methanol gas, air, water vapour and exhaust gas and feeding into a reactor for oxidation reaction; gas generated by oxidation reaction is fed into a formaldehyde absorbing tower for absorption reaction consisting of a lower circulating absorption at the bottom of the formaldehyde absorbing tower, a middle circulating absorption in the middle of the formaldehyde absorbing tower and a bubble cap absorption at the top of the formaldehyde absorbing tower, and is characterized in that the absorption reaction also comprises an upper circulating absorption at the upper portion of the formaldehyde absorbing tower. The technology integrates the independent absorbing tower and the dealcoholizing tower into one tower, completely eliminates the external heat power supply of the dealcoholizing tower. The heat required by the rectification is supplied by the absorbing tower. The energy consumption of the polyoxymethylene production is reduced and the economic benefit is improved greatly.

Description

technical field [0001] The invention relates to a chemical processing and purification technology, in particular to a formaldehyde absorption tower alcohol removal technology. Background technique [0002] Formaldehyde is an important basic organic chemical raw material and is widely used in the chemical industry. This year, my country's annual formaldehyde production has exceeded 10 million tons. However, there is a technical problem of high alcohol content in formaldehyde in the production of formaldehyde by the prior art, which greatly affects the quality and use effect of formaldehyde. [0003] In the prior art, the most commonly used method is to oxidize methanol to formaldehyde using the silver method. [0004] The formaldehyde oxidation process mainly refers to the oxidation reaction process after the quaternary gas is mixed, such as figure 2 As shown, the details are as follows: [0005] Methanol is vaporized after being heated in the methanol evaporator 5 and th...

AI Technical Summary

Problems solved by technology

However, the use of traditional technology to produce formaldehyde has increased problems: first, the content of methanol in formaldehyde products is relatively high, generally 0.5-10%, which exceeds the alcohol content requirements of some downstream processes, and high methanol content leads to low conversion rates. Production high cost

In addition, the use of traditional technology catalysts has a short service life. Generally, it needs to be shut down to replace the catalyst within 1-3 months. During the shut down period, the quality of formaldehyde is not stable enough, and the content of methanol often fluctuates, which affects the stable operation of downstream processes.

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