Methanol separation method and device

Abstract

The present invention relates to a separated method for carbinol and the corresponding device; the technical scheme is that: the separated method for carbinol includes the following steps: 1) the mixed gases from the carbinol reaction tower are cooled to 25-70 Celsius system; 2) the mixed gases after being cooled is taken with the basic machine gas / liquid separation; 3) the mixed gases after being separated by the machine mode is absorbed to high concentration by the absorbing liquid; 4) the absorbing liquid mixed with the mixed gases after being absorbed by the absorbing liquid is wiped off. The present invention can solve the problem of the harm of carbinol in the common technology; the present invention can become a large-scale / super-large scale separated method and the corresponding device with the most newest, effective and economical.

Description

technical field [0001] The invention relates to a methanol separation method and a device thereof. Background technique [0002] The methanol synthesis reaction is a high-temperature, high-pressure, high-energy-consuming process with a very low conversion rate (domestic catalyst 4-7%, imported 10-17%), and the net value of alcohol is only 3-6% (imported 9-16%). Due to the high temperature of the synthesizer Above 230°C, the reaction product methanol is mixed in the unconverted raw material gas in the form of gaseous molecules. In order to obtain methanol products and continue the reaction of the unconverted raw material gas, the methanol gas must be effectively separated from the raw material gas. Can realize industrial production. For decades, the traditional methanol separation method is gas cooling--gas / liquid phase separation (mechanical method or coalescence method), that is, (1) cooling the mixed gas to be separated leaving the methanol reaction tower, and cooling the...

AI Technical Summary

Problems solved by technology

Due to the low separation efficiency of traditional separators, it is impossible to separate methanol liquid mist below 5um

Several Chinese patents (patent numbers 98233174.6, 98233173.8 and 200420042280.4) applied by the inventor himself disclose several coalescing synthetic ammonia alcohol, ammonia, and oil separators that use coalescing filter elements to separate methanol. The separation accuracy is as high as 0.01 μm. Although it greatly improves the separation accuracy of methanol, the separated gas still contains methanol of less than 0.01 μm. Therefore, it only alleviates the severity of the hazard of methanol, but it cannot completely solve the problem caused by the unseparated methanol. the harm of

At the same time, due to the ultra-fine fiber structure and high price of the coalescing filter element, the coalescer can only be used effectively under the conditions of clean gas / stable / no solid impurities, but in the current large-scale, complex working conditions, catalyst In the continuous industrial production of methanol, where there are solids such as powder / pipeline rust / waxy by-products, and the gas size and pressure fluctuate, the polymerizer cannot be used alone (it must be used after a series of mechanical separators, resulting in double the price), and it is very expensive. It is easy to achieve effective separation due to blockage and damage of the filter element

Generally, it cannot be used in large-scale devices due to shortcomings such as short service life, high price, unstable effect, and incomplete separation.

[0003] The traditional methanol separation method is also unable to further reduce the gas temperature due to the limitation of energy consumption and cooling medium. The methanol molecules in the mixed gas cannot be condensed into a liquid state, and the lowest value is still 0.2%-0.6%. sandwiched in raw gas

Some processes use water washing and absorption methods to separate gaseous methanol, but due to high energy consumption (low absorption efficiency produces a large amount of low-concentration 10%-25% dilute methanol, resulting in increased rectification load and excessive total energy consumption) and new water mist Various problems such as entrainment (absorbing liquid cannot be effectively separated, causing circulation and liquid-carrying work, and synthesis tower flooding accident) cannot be realized in industrial applications. Product separation of production main line cycle gas

[0004] As a result of the above problems, the methanol product accounting for 0.5%-1.8% of the total recycle gas cannot be "taken out" due to separation problems, and it is repeatedly circulated in the system and consumes energy, which not only causes product loss and low alcohol net value , affect the production capacity of the device, and reduce the reaction driving force and aggravate the side reactions, increase the raw gas consumption quota, and seriously endanger the downstream working conditions, resulting in liquid shock (single alcohol) of the circulator and abnormal copper washing operation ( Alcohol), leading to permanent catalyst poisoning and deactivation

Images