Process for recovering iodine from industrial tail liquid and preparing polarization liquid and potassium iodide from recovered iodine

Abstract

The invention provides a preparation process for recovering iodine from industrial tail liquid, preparing polarization liquid from the recovered iodine and producing potassium iodide, wherein the preparation process sequentially comprises the following seven steps: pretreating and classifying iodine-containing wastewater to be extracted, reacting to generate solid iodine, centrifugally dewatering, extracting iodine by steam and recycling, absorbing iodine gas, and preparing the potassium iodide and the polarization liquid. According to the preparation process, the solid iodine can be recovered from iodine-containing wastewater or concentrated iodine liquid in the industrial tail liquid according to the preparation process, the solid iodine can be purified into the electronic-grade iodine, the electronic-grade iodine can be further made into the polarization liquid, and meanwhile, the tail liquid can directly enter a wastewater plant to achieve the emission standard.

Description

technical field [0001] The invention belongs to the technical field of high-end equipment, and in particular relates to a preparation process for recovering iodine from industrial tail liquid and preparing polarizing liquid and potassium iodide by using the recovered iodine. Background technique [0002] According to relevant data, the domestic polarizer market size in 2017 was US$3.54 billion, a year-on-year increase of 27.3%, accounting for 29.9% of the global market share. It is estimated that by 2020, the domestic polarizer market will reach US$5.32 billion, accounting for 40.2% of the global market. Under the dual effects of production line construction and a huge downstream market, China will become the market with the largest new demand for polarizers in the world, and the self-sufficiency rate of domestic polarizers is expected to further increase. [0003] The production of polarizers mainly includes extension method and coating method. The extension method is the ...

AI Technical Summary

Problems solved by technology

The main manufacturers of iodine and iodine-containing compounds in the world include Chilean SQM Company, ACF, Japan Ise Chemicals, Wang Takigawa Godo Shigen Company, etc. This situation also leads to the concentration of raw materials, and because most enterprises have poor or no recycling mechanisms, resulting in waste of resources , while most of them rely on imports, and the cost is high

[0006] In addition, most of the discharged iodine-containing polarizing fluid has a large discharge volume and high COD characteristics. On the one hand, it cannot meet the discharge standard and cannot be directly discharged into the sewage treatment plant. On the other hand, the cost of outsourcing treatment and discharge is high. There is no suitable recycling mechanism and method, which has become an urgent problem to be solved

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