Zero emission system device for desulfurization wastewater evaporated by drying tower after concentration

Abstract

The invention discloses a zero emission system device for desulfurization wastewater evaporated by a drying tower after concentration. The zero emission system device comprises a pre-treatment unit, a membrane concentration unit and an air pre-heater bypass drying unit, wherein the pre-treatment unit is connected with the membrane concentration unit; the membrane concentration unit is connected with the air pre-heater bypass drying unit; the pre-treatment unit comprises an integrated high-efficiency sedimentation tank and a microfiltration device; the membrane concentration unit comprises a first-grade special middle-high pressure reverse osmosis membrane system and a second-grade seawater desalination reverse osmosis membrane concentration system; the air pre-heater bypass drying unit comprises a wastewater drying tower feeding box, a drying tower high-level water tank, a spray-drying tower, an air pre-heater and an SCR (Selective Catalytic Reduction) reactor. According to the device disclosed by the invention, a scheme of softening and concentration and evaporation of an air pre-heater bypass drying tower is adopted so that zero emission of the desulfurization wastewater is realized; produced fresh water is recycled and used as supplementing water of demineralized water of a boiler; evaporation is realized by adopting flue gas residual heat and an evaporation tower can be overhauled independently from a host system.

Description

technical field [0001] The invention relates to a zero-discharge system device for desulfurization wastewater evaporated by a drying tower after being concentrated. Background technique [0002] my country is a country that mainly uses coal-fired thermal power plants to generate electricity, and emits a large amount of sulfur dioxide every year. Now the flue gas of thermal power plants mainly uses limestone wet desulfurization technology. Along with desulfurization technology comes the problem of desulfurization wastewater treatment and recycling. In recent years, the requirements of the environmental protection department have become increasingly strict, and the national environmental protection department requires desulfurization wastewater to meet the zero discharge standard. [0003] There are many problems in the existing zero-discharge technology of desulfurization wastewater. For example, the investment and operation cost of the evaporation crystallization method is e...

AI Technical Summary

Problems solved by technology

[0003] There are many problems in the existing zero-discharge technology of desulfurization wastewater, for example, the investment and operation cost of the evaporation crystallization method is extremely high; the flue spray method is easy to cause scaling and corrosion of the flue and the electric bag filter, and the main machine needs to be shut down during maintenance

Images