A comprehensive disposal system for resource utilization of chlor-alkali industrial salt mud

Abstract

A comprehensive disposal system for resource utilization of salt mud in the chlor-alkali industry, including a pretreatment unit, a product recovery unit, and a waste water and waste gas treatment and recovery unit. The salt mud is sent to the first stirring reactor to react with hydrochloric acid, and the reaction liquid is removed by a decanter centrifuge. The residue is then sent to the second stirred reactor to react with oxalic acid to form calcium oxalate precipitate; the reaction solution containing calcium oxalate precipitate is left to settle, centrifuged, washed and dried to obtain calcium oxalate product; Stirred reaction kettle, part of the centrifugal liquid and washing liquid are sent to the third stirred reaction kettle to react with sodium hydroxide to form magnesium hydroxide precipitate, and the reaction solution containing magnesium hydroxide precipitate is left to settle, centrifuged, washed with water and dried to obtain hydroxide Magnesium product; static precipitation supernatant, centrifuge and washing liquid are sent into buffer tank; the HCl gas of concentrated hydrochloric acid storage tank is sent into the first stirring reactor during operation, and is sent into hydrochloric acid absorption tower when parking; the present invention realizes Green and environmentally friendly recycling of salt mud.

Description

technical field [0001] The invention relates to the technical field of chlor-alkali industrial salt mud resource utilization, in particular to a chlor-alkali industrial salt mud resource comprehensive disposal system. Background technique [0002] The chlor-alkali industry plays a very important role in the national economy. With the development of the chlor-alkali industry, the problem of salt sludge disposal in the chlor-alkali industry has become more and more prominent. The disposal methods of chlor-alkali industrial salt sludge are basically limited to press filtration to recover brine, and the remaining materials are stacked or landfilled. Because the chlor-alkali industrial salt sludge contains a large number of inorganic salts for use, random stacking and landfill not only seriously wastes resources, but also pollutes the soil, water and even the atmosphere, endangering social security. [0003] Chlor-alkali industrial salt sludge is a mixture of various inorganic s...

AI Technical Summary

Problems solved by technology

At present, researchers at home and abroad have done a lot of scientific research on the resource utilization of chlor-alkali industrial salt mud, but it is mainly used as a filler for industrial production, while other resource recycling processes only exist in In the experimental stage, there are no engineering examples

[0004] The solution to the three wastes produced in the recycling process of chlor-alkali industrial salt mud is the main problem that limits its engineering application, such as the waste gas produced in the process of hydrochloric acid pickling; in addition, most of the currently recycled inorganic salt chemical production raw materials are MgCO 3 , CaCO 3 , MgO and other low value-added substances, and the cost of the recycling process is high, it is difficult to generate economic benefits

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