Pressure control recovery equipment and process for glyphosate hydrolysis tail gases produced by alkyl ester method

Abstract

The invention relates to pressure control recovery equipment and process for glyphosate hydrolysis tail gases produced by an alkyl ester method. A pretreatment system for glyphosate hydrolysis tail gases produced by the alkyl ester method is connected with a dilute methanol solution collection tank; the dilute methanol solution collection tank is connected with the upper part of a methylal rectifying column by virtue of a pipeline; the top of the methylal rectifying column is connected with a methylal rectifying column return tank by virtue of a condenser I; the methylal rectifying column return tank is connected to a methylal finished product tank; the bottom of the methylal rectifying column is connected with a methanol aqueous solution intermediate tank by virtue of a pipeline; the methanol aqueous solution intermediate tank is connected with a methanol rectifying column by virtue of a pipeline; the top of the methanol rectifying column is connected with a methanol rectifying columnreturn tank by virtue of a condenser III; and the methanol rectifying column return tank is connected to a methanol finished product tank. Meanwhile, the invention discloses specific process steps. The energy consumption for solvent recovery is reduced by virtue of pressure control condensation and reduced pressure gasification measures, the hydrolysis tail gas recovery stability is improved, anda highly dependent damageable graphite condenser in an original liquid phase recovery process is not used.

Description

technical field [0001] The invention belongs to new equipment and technology for producing glyphosate solvent by alkyl ester method. Background technique [0002] Brief Introduction of Glyphosate Process [0003] Glyphosate is a high-efficiency, low-toxicity, broad-spectrum, destructive, non-selective herbicide with excellent biological characteristics. Currently, there are two mainstream production processes for glyphosate in China: the alkyl ester method and the iminodiacetic acid method. The production process abroad is mainly the iminodiacetic acid method of Monsanto Company in the United States, and the mainstream process for glyphosate production in my country is the alkyl ester method. The alkyl ester method is mainly the glycine-dialkyl phosphite method, and there are also small chloroacetic acid-alkyl ester methods that use chloroacetic acid as the starting material to produce glyphosate and the glycine-trimethyl phosphite method, etc. public routes. [0004] Br...

AI Technical Summary

Problems solved by technology

[0009] This method is easy to operate but has the disadvantages of being highly dependent on graphite condensers, poor in intrinsic safety and high energy consumption: the hydrolysis tail gas of this process is acidic gas containing a large amount of hydrogen chloride, so it is highly dependent on graphite condensers

[0011] This method has less phase change and low energy consumption, but has the disadvantages of poor operation stability: First, the remaining tail gas after hydrolyzing the tail gas to remove hydrogen chloride gas is composed of methylal (A)-methanol (B)-water (C)-chloromethane The quaternary mixed liquid system composed of (D) has a large total amount of materials, a large logistics load (1.5 times that of the liquid phase) and a large proportion of methyl chloride components (accounting for 30% of the total tail gas) compared with the liquid phase route, resulting in Recycling system is not working properly

Especially in the event of an emergency power failure, a large amount of methylal (A), methanol (B), and methyl chloride (D) material systems are discharged from the emergency pressure relief system to release pressure. Therefore, poor operation stability presents great safety and environmental protection risks

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