Method for preparing high-purity sodium formate with tail gas of yellow phosphorus stove

Abstract

The invention discloses a method for preparing high purity sodium formate with the tail gas of a yellow phosphorus furnace; the tail gas of the yellow phosphorus furnace is firstly purified, and then reacts with alkali liquor to synthesize sodium formate. The invention is characterized in that the wet PDS is adopted for desulphurization; the desulphurized tail gas enters into a decarburization device, and PSA variable pressure is used for adsorption and decarburization; the purified tail gas reacts with alkali liquor under the conditions of 2.3-2.5 Mpa and 230 DEG C to synthesize sodium formate. The process can be described as follows: firstly the tail gas of the yellow phosphorus furnace is washed with first class water, pumped out by a water ring pump, and delivered to a second class water washing tower and a floating ball type water washing tower, and then delivered to a coke filter to filter the solid impurities and enters into a adsorber and a desulphurization tower; the desulphurized gas is delivered to the first part and the second part of a compressor, and then delivered to the decarburization device after being pressurized; the decarburized gas is delivered to the third part of the compressor, and pressurized to obtain purified feed gas which can react with the alkali liquor in a synthesizer to synthesize the sodium formate. The invention can realizes that the device for preparing high purity sodium formate with the tail gas of a yellow phosphorus furnace can run in large-scale, cleaning and long period, and is suitable to be used for the enterprises preparing high purity sodium formate with the tail gas of the yellow phosphorus furnace.

Description

technical field [0001] The present invention relates to the salt of formic acid, also relates to the production of yellow phosphorus, specifically, relates to the method that the tail gas discharged from the electric furnace producing yellow phosphorus is used for producing sodium formate. Background technique [0002] As we all know, the exhaust gas from electric furnaces producing yellow phosphorus (referred to as yellow phosphorus furnace tail gas) can be used to produce sodium formate, because the main component of yellow phosphorus furnace tail gas is carbon monoxide, and carbon monoxide gas and soluble strong alkali can directly synthesize formate. Among the Chinese patent applications, No. CN1456546 "The method for preparing potassium formate and sodium with calcium carbide furnace tail gas as raw material", No. CN101070280 "The method for preparing sodium formate by using carbon monoxide in the tail gas of calcium carbide furnace and coke oven", No. CN101117313 "A hig...

AI Technical Summary

Problems solved by technology

However, the existing formate production units generally have problems such as small scale (each scale ≤ 5kt / a), short operation period, unsatisfactory product quality, and environmental pollution caused by exhaust gas emissions during the production process.

The main reasons are as follows: ① The tail gas purification process is backward, and it is difficult to completely remove dust, desulfurization, and decarbonization by using traditional water washing and alkali washing. "Phenomenon, it cannot run for a long period of time; ②The reaction pressure control in the process conditions of synthesizing sodium formate is low, generally 1.4-1.96MPa, so that the production scale cannot be enlarged; ③Because the alkali washing liquid used for purification needs to be regenerated, the effect of causticization method is poor ; If the production of sodium salt is changed, a large amount of hydrogen sulfide gas will be produced to pollute the environment; ④ Unwashed phosphorus mud will produce phosphine during the alkali washing process, which will also seriously pollute the environment

It can be seen that the traditional method has many defects

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