Zero-discharge system and technology of desulphurization waste water based on ion selective electrodialysis technology

Abstract

The invention relates to a zero-discharge system and technology of desulphurization waste water based on an ion selective electrodialysis technology. According to the system, a softening pretreatment mechanism comprises a reaction groove, a clarifier and a filter device, and a reduction concentration mechanism is an ED ion membrane device. Fresh water precipitated by the ED ion membrane device is reused as make-up water for a desulfurization system, or is reused through the concentration of a reverse osmosis membrane, reverse osmosis membrane concentrated water returns to the process before softening pretreatment, and circulation treatment is conducted. According to the zero-discharge system and technology, through the treatment of a three-linkage-box technology, lime is adopted and the pH of the lime is adjusted to 9-9.5, no alkali needs to be added to adjust the pH to 11 or above, the addition amount of the lime is small, few calcium ions are carried in, the calcium ions can generate precipitated sodium carbonate or sodium sulfate without adding more calcium ions, and after clarification and precipitation, filtered water directly enters the ED ion membrane device to be reduced and concentrated. Compared with the prior art, the technology processes are short, the operation and investment cost is low, the system is convenient to maintain, the ion selective electrodialysis technology is adopted, and the system has the advantages of being long in service life, low in requirement for water quality, high in concentration multiple, low in operation load and little in energy consumption.

Description

technical field [0001] The invention belongs to the technical field of environmental protection water treatment, and in particular relates to a desulfurization wastewater zero discharge system and process based on ion-selective electrodialysis technology. Background technique [0002] Sulfur dioxide (chemical formula SO2) is one of the main causes of air pollution and an important cause of acid rain. It is one of the main pollutants in the atmosphere. The gas is emitted during volcanic eruptions and is also produced in many industrial processes. Since coal and petroleum typically contain elemental sulfur, sulfur dioxide is formed when burned. When sulfur dioxide dissolves in water, sulfurous acid is formed. If sulfurous acid is further oxidized in the presence of PM2.5, sulfuric acid will be produced rapidly and efficiently. This is one reason for concern about the environmental effects of using these fuels as energy sources. [0003] As of the end of 2010, my country's ...

AI Technical Summary

Problems solved by technology

Solve the problems of high concentration calcium and magnesium ion desulfurization wastewater softening pretreatment need to add a large amount of lime and sodium carbonate agents, high operating costs, large amount of sludge, long process flow, high equipment investment, etc.

Images