阅读说明：本技术 一种降低烟气法工业硫酸色度的工艺方法 (Process method for reducing chromaticity of industrial sulfuric acid by flue gas method ) 是由 王进龙 张析 王军 李飞 吴斌 周涛 刘守信 白守元 于 2021-08-18 设计创作，主要内容包括：本发明涉及一种降低烟气法工业硫酸色度的工艺方法,该方法是指将烟气法工业硫酸置于反应器中,然后向所述反应器中通氧气,于40℃氧化反应0.5h；最后,按质量份数计,每500份所述烟气法工业硫酸缓慢滴加2～5份质量浓度为35%的过氧乙酸；滴加完毕,降温至20～25℃时过滤,即得脱色工业硫酸成品。本发明提高了脱色后硫酸在贮存过程中的稳定性,有效解决了脱色后硫酸的黄变现象,提高了硫酸品质,且经过长期储存不变色。(The invention relates to a process method for reducing the chromaticity of industrial sulfuric acid by a flue gas method, which comprises the steps of placing the industrial sulfuric acid by the flue gas method in a reactor, introducing oxygen into the reactor, and carrying out oxidation reaction for 0.5h at 40 ℃; finally, according to the mass parts, 2-5 parts of peroxyacetic acid with the mass concentration of 35% is slowly dripped into every 500 parts of the flue gas method industrial sulfuric acid; and after the dropwise addition is finished, cooling to 20-25 ℃, and filtering to obtain a decolorized industrial sulfuric acid finished product. The invention improves the stability of the decolored sulfuric acid in the storage process, effectively solves the yellowing phenomenon of the decolored sulfuric acid, improves the quality of the sulfuric acid, and does not change color after long-term storage.)

1. A process method for reducing the chromaticity of industrial sulfuric acid by a flue gas method is characterized by comprising the following steps: the method is that industrial sulfuric acid produced by a flue gas method is placed in a reactor, then oxygen is introduced into the reactor, and oxidation reaction is carried out for 0.5h at 40 ℃; finally, according to the mass parts, 2-5 parts of peroxyacetic acid with the mass concentration of 35% is slowly dripped into every 500 parts of the flue gas method industrial sulfuric acid; and after the dropwise addition is finished, cooling to 20-25 ℃, and filtering to obtain a decolorized industrial sulfuric acid finished product.

2. The process method for reducing the chromaticity of industrial sulfuric acid by a flue gas method according to claim 1, which is characterized in that: the flue gas method industrial sulfuric acid is sulfuric acid which is prepared from lead-zinc smelting flue gas, has the mass concentration of 93 percent and is black in appearance.

3. The process method for reducing the chromaticity of industrial sulfuric acid by a flue gas method according to claim 1, which is characterized in that: the reactor is a device equipped with stirring, heating, cooling and oxygen introduction pipes.

4. The process method for reducing the chromaticity of industrial sulfuric acid by a flue gas method according to claim 1, which is characterized in that: the oxygen is industrial oxygen, and the oxygen content is more than or equal to 99.5 percent according to volume fraction.

5. The process method for reducing the chromaticity of industrial sulfuric acid by a flue gas method according to claim 1, which is characterized in that: the peroxyacetic acid is an industrial grade first-grade product, and the dropping speed of the peroxyacetic acid is 0.2-0.4 L.min^-1。

6. The process method for reducing the chromaticity of industrial sulfuric acid by a flue gas method according to claim 1, which is characterized in that: the filtration is carried out by a WTM-CM-01-024 ceramic membrane separator.

Technical Field

The invention relates to the technical field of inorganic chemical industry, in particular to a process method for reducing the chromaticity of industrial sulfuric acid by a flue gas method.

Background

The smelting flue gas sulfuric acid is prepared by the processes of dust removal, wet purification, dry absorption, conversion, absorption and the like of sulfur dioxide gas generated when metal sulfide ores are roasted in a smelting furnace, the quality of prepared sulfuric acid products is influenced by various factors such as metal mineral raw materials, smelting processes, purification processes and the like, and the sulfuric acid produced by a plurality of enterprises has quality problems of different degrees.

In a certain domestic lead-zinc smelting plant, anthracite self-made coal gas is used as a fuel, acid is prepared by sintering flue gas, and sulfuric acid produced by a sulfuric acid system always has the phenomenon of abnormal chromaticity, and is mainly shown to be reddish brown in color. Research shows that coal gas is generated by the gasification reaction of anthracite in a coal gas producer, and due to the reasons of organic matters in the coal gas, partial incomplete combustion of the coal gas and the like, the coal gas enters a flue gas system and cannot be completely collected in a purification process, so that the coal gas enters finished acid and is further carbonized into submicron carbon particles. From the analysis of the smelting process, nitrogen oxides are brought in by air, fuel, nitrogenous beneficiation reagent and the like in the roasting process of minerals, and the reaction of iron and sulfuric acid is aggravated due to the existence of the nitrogen oxides, so that the color of the sulfuric acid is abnormal. Therefore, the dissolved reducing gases, such as sulfur dioxide and the like, as well as submicron carbon particles and nitrogen oxides in the sulfuric acid product are the main cause of the reddish brown color of sulfuric acid.

The reasons for the sulfuric acid coloring by the flue gas method are also manifold, the sulfuric acid decoloring technology is solved, the key points are that a good decoloring effect can be achieved only by a proper oxidant and a reasonable decoloring technology on the selection and decoloring technology of the oxidant, the decoloring cost is lower, and good economic benefits are obtained.

Chinese patent 201510248073.7 discloses a process for reducing the chromaticity of industrial sulfuric acid by air-hydrogen peroxide combined oxidation, which comprises placing industrial colored sulfuric acid into a reactor, introducing air and dropwise adding hydrogen peroxide to carry out oxidation and decolorization reaction, so as to decolorize the colored sulfuric acid. However, when the method is used for a long time, the sulfuric acid which is decolorized at room temperature can be yellowed in 6 months in the storage process, namely the color of the sulfuric acid gradually becomes yellow, and the quality of the sulfuric acid is influenced. By analyzing the product obtained by the method, two problems mainly exist: firstly, the method can not oxidize coloring impurities completely, and secondly, the impurities after oxidation can not be filtered completely, so that the sulfuric acid has yellowing phenomenon in storage.

Disclosure of Invention

The invention aims to solve the technical problem of providing a process method for reducing the chromaticity of industrial sulfuric acid by a flue gas method, which improves the storage stability of decolored sulfuric acid and does not discolor after long-term storage.

In order to solve the problems, the invention provides a process method for reducing the chromaticity of industrial sulfuric acid by a flue gas method, which is characterized by comprising the following steps: the method is that industrial sulfuric acid produced by a flue gas method is placed in a reactor, then oxygen is introduced into the reactor, and oxidation reaction is carried out for 0.5h at 40 ℃; finally, according to the mass parts, 2-5 parts of peroxyacetic acid with the mass concentration of 35% is slowly dripped into every 500 parts of the flue gas method industrial sulfuric acid; and after the dropwise addition is finished, cooling to 20-25 ℃, and filtering to obtain a decolorized industrial sulfuric acid finished product.

The flue gas method industrial sulfuric acid is sulfuric acid which is prepared from lead-zinc smelting flue gas, has the mass concentration of 93 percent and is black in appearance.

The reactor is a device equipped with stirring, heating, cooling and oxygen introduction pipes.

The oxygen is industrial oxygen, and the oxygen content is more than or equal to 99.5 percent according to volume fraction.

The peroxyacetic acid is an industrial grade first-grade product, and the dropping speed of the peroxyacetic acid is 0.2-0.4 L.min^-1。

The filtration is carried out by a WTM-CM-01-024 ceramic membrane separator.

Compared with the prior art, the invention has the following advantages:

1. the invention adopts a method of introducing oxygen into the sulfuric acid solution for the flue gas method industrial sulfuric acid, so that the dissolved sulfur dioxide overflows, and the problem of incomplete oxidation is avoided.

2. The invention simultaneously adopts an oxygen and oxidant combined oxidation method to oxidize and precipitate the reducing substances in the sulfuric acid solution; in addition, the combined oxidant can oxidize and decompose the submicron carbon particles and the nitrogen oxides, so that the coloring phenomenon of the submicron carbon particles and the nitrogen oxides is avoided, and impurities are filtered by the ceramic membrane, so that the stability of the sulfuric acid after decolorization in the storage process is improved, the yellowing phenomenon of the sulfuric acid after decolorization is effectively avoided, and the quality of the sulfuric acid is improved.

3. The method is characterized in that the filtrate obtained by filtering impurities through a ceramic membrane is a clear and transparent industrial sulfuric acid product, and the quality index of the sulfuric acid reaches the index requirement of a GB/T534-2002 first-grade product through detection and analysis. Meanwhile, the decolored flue gas method sulfuric acid product is subjected to storage test, and does not generate yellowing at room temperature for 2 years.

Detailed Description

A process method for reducing the chromaticity of industrial sulfuric acid by a flue gas method comprises the steps of placing the industrial sulfuric acid by the flue gas method in a reactor, introducing oxygen into the reactor, and carrying out oxidation reaction for 0.5h at 40 ℃; finally, according to the mass parts, 2-5 parts of peroxyacetic acid with the mass concentration of 35% is slowly dripped into every 500 parts of flue gas method industrial sulfuric acid, and the dripping speed is 0.2-0.4 L.min^-1(ii) a And after the dripping is finished, cooling to 20-25 ℃, and filtering by adopting a WTM-CM-01-024 ceramic membrane separator of Hangzhou Woltm membrane engineering Co.

Wherein: the flue gas method industrial sulfuric acid is sulfuric acid which is prepared from lead-zinc smelting flue gas, has the mass concentration of 93 percent and is black in appearance.

The reactor means a device equipped with stirring, heating, cooling and oxygen introduction pipes.

The oxygen is industrial oxygen, and the oxygen content is more than or equal to 99.5 percent according to volume fraction.

The peroxyacetic acid is a first-grade industrial product.

Embodiment 1 a process for reducing chromaticity of flue gas process industrial sulfuric acid, the process comprises placing 500kg of flue gas process industrial sulfuric acid in a reactor, then opening an oxygen cylinder valve, introducing oxygen into the reactor, controlling the flow of oxygen at 40-60L/min, controlling the pressure at 0.2MPa, and carrying out oxidation reaction at 40 ℃ for 0.5 h; finally, 2kg of peroxyacetic acid with the mass concentration of 35% is slowly dripped at the dripping speed of 0.2 L.min^-1(ii) a And after the dripping is finished, cooling to 20-25 ℃, and filtering by adopting a WTM-CM-01-024 ceramic membrane separator of Hangzhou Woltm membrane engineering Co.

Example 2 a process for reducing the chromaticity of flue gas process industrial sulfuric acid,the method comprises the steps of putting 500kg of flue gas process industrial sulfuric acid into a reactor, then opening an oxygen cylinder valve, introducing oxygen into the reactor, controlling the flow of the oxygen at 40-60L/min and the pressure at 0.2MPa, and carrying out oxidation reaction at 40 ℃ for 0.5 h; finally, 3.5kg of peroxyacetic acid with the mass concentration of 35% is slowly dripped at the dripping speed of 0.3 L.min^-1(ii) a And after the dripping is finished, cooling to 20-25 ℃, and filtering by adopting a WTM-CM-01-024 ceramic membrane separator of Hangzhou Woltm membrane engineering Co.

Embodiment 3 a process for reducing the chromaticity of flue gas process industrial sulfuric acid, the process comprising placing 500kg of flue gas process industrial sulfuric acid in a reactor, then opening an oxygen cylinder valve, introducing oxygen into the reactor, controlling the flow of oxygen at 40-60L/min, controlling the pressure at 0.2MPa, and carrying out oxidation reaction at 40 ℃ for 0.5 h; finally, 5kg of peroxyacetic acid with the mass concentration of 35% is slowly dripped at the dripping speed of 0.4 L.min^-1(ii) a And after the dripping is finished, cooling to 20-25 ℃, and filtering by adopting a WTM-CM-01-024 ceramic membrane separator of Hangzhou Woltm membrane engineering Co.

The results of the analysis and assay of the samples of the finished sulfuric acid obtained in examples 1 to 3 are shown in Table 1. The result shows that the quality of the sulfuric acid treated by the process method reaches the first-grade product index requirement of national standard GB/T534-2002 of industrial sulfuric acid.

TABLE 1 sulfuric acid product analysis test results