Desulfurization waste water zero discharge processing system and processing method

Abstract

The invention discloses a desulfurization waste water zero discharge processing system and a processing method. The desulfurization waste water zero discharge processing system comprises a regulation sedimentation basin, triple connecting tanks, a defecator and a nanofilter which are connected in sequence, wherein the concentrated water outlet end of the nanofilter is connected with a mistorizer which sprays the concentrated water into a chimney flue; the triple connecting tanks include a neutralization tank, a reaction tank and a flocculation tank which are connected in sequence, wherein the neutralization tank is communicated with the water outlet of the regulation sedimentation basin, and is used for adjusting the pH value of desulfurization waste water, so that bicarbonate ions in the desulfurization waste water are removed; the reaction tank provides a reaction chamber for removing calcium ions in the desulfurization waste water; the flocculation tank is connected with the defecator. The desulfurization waste water zero discharge processing system and the processing method have the advantages of saving the cost of the agent for removing magnesium ions in the desulfurization waste water, reducing the quantity of sludge, lowering the operating cost, using no lime milk and improving the site working conditions. The sodium chloride salt in the waste water is purified and then crystallized, thus the recycle of the sodium chloride salt in the desulfurization waste water is achieved, the solid waste disposal cost is reduced, and certain economic benefits are produced.

Description

technical field [0001] The invention relates to the field of industrial wastewater treatment, in particular to a zero-discharge treatment system and treatment method for desulfurization wastewater discharged from a thermal power plant wet flue gas desulfurization system. Background technique [0002] Desulfurization wastewater is produced from wet flue gas desulfurization system. At present, limestone-gypsum wet flue gas desulfurization is the most widely used in thermal power plant flue gas desulfurization. In order to maintain the balance of substances in the slurry circulation system of the desulfurization device and prevent the concentration of chloride ions in the desulfurization slurry from exceeding the specified Value and to ensure the quality of gypsum, a certain amount of wastewater must be discharged from the system. The desulfurization wastewater has a pH of 4-6, and there are a large amount of suspended matter (gypsum, silicon dioxide) with high salt content, ma...

AI Technical Summary

Problems solved by technology

Fly ash is mainly used in the concrete and cement industry, and the relevant standards of the concrete and cement industry "GBT 1596-2005 for fly ash in cement and concrete" and "JGJ55-2011 Ordinary Concrete Mixing Design Regulations" The content requirements are very strict, and the direct use of flue evaporation process for desulfurization wastewater will affect the quality of fly ash, making it unusable for concrete, cement and other industries, and can only be disposed of in landfill, resulting in a waste of resources

In addition, the desulfurization wastewater is acidic and contains a large amount of chloride ions. When the evaporation is not complete, it is easy to cause corrosion to the flue under high temperature conditions.

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