Technique for producing sodium sulfite products by absorption of SO2 flue gas through arsenic-containing industrial alkali residue water alkali liquor and arsenic removal purification

Abstract

A kind of technological method of using arsenic-containing industrial alkali slag to absorb SO2 flue gas, remove arsenic and purify to produce sodium sulfite product. After treatment with p-phenylenediamine, press filter to obtain arsenic-containing leaching lye for later use, pump the clear liquid into the spray desulfurization tower to absorb SO2 flue gas, reduce the pH value of the absorption solution to 6.2-6.4, and then add arsenic-containing leaching lye After adjusting the pH value of the clear liquid to 10.5-11.5, adding polyferric sulfate aqueous solution for arsenic precipitation, pressure filtration for liquid-solid separation, clear liquid crystallization after concentration and evaporation, and drying after separating the mother liquor to obtain sodium sulfite products with a mass concentration ≥ 96% . This method starts with industrialized stable production, increases the content of sodium sulfite products as much as possible, optimizes the technical process and parameter selection, and has achieved obvious technological progress. Based on the annual output of 20,000 tons of alkali slag in the country, it can increase economic benefits by about 35 million The total amount of arsenic that can be removed and harmlessly treated is As 6%×20000=1200 tons / year, and the desulfurization is 4250 tons / year, resulting in huge environmental benefits.

Description

technical field [0001] The invention relates to the non-ferrous smelting industry, in particular to flue gas desulfurization and inorganic chemical technology, and in particular to a method for soaking lye with arsenic-containing industrial alkali slag to absorb SO in smelting flue gas. 2 The method for removing arsenic and purifying and producing sodium sulfite products. Background technique [0002] In the non-ferrous smelting industry, a large amount of flue gas dust is often produced, which is collected and recovered by cloth bags. Because of its high content of lead, antimony, etc., and a certain amount of arsenic, it is generally used to recover valuable metals by reverberatory furnace reduction and smelting. To make slag, a large amount of soda ash is added to form high-alkali dilute slag. Most of the arsenic in the smoke enters into the high-alkali dilute slag, and it is released outside the furnace. After the mold is cooled, it is commonly known as arsenic-containin...

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Problems solved by technology

In summary, CN101899574A proposed the idea of ​​treating waste with waste, and proposed technical process condition parameters under laboratory conditions, but did not go deep into industrial scale production, especially the research on how to stably produce high-content sodium sulfite products. Not doing enough, no practical value

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