Method for carrying out desalination and zero-discharge processing of power plant desulphurization wastewater by adopting electrodialysis technology

A desulfurization wastewater and electrodialysis technology, which is applied in the direction of gaseous effluent wastewater treatment, water/sewage multi-stage treatment, water/sludge/sewage treatment, etc., can solve equipment corrosion, soil salinization, increase in water body salt concentration, etc. problems, to achieve the effects of improving operational stability, realizing resource utilization and zero-discharge treatment, and reducing fresh water consumption

Active Publication Date: 2015-02-18
INST OF PROCESS ENG CHINESE ACAD OF SCI
View PDF15 Cites 56 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0008] The technical problem of the present invention is to overcome the deficiencies of the prior art, and provide a method of using electrodialysis technology to realize zero-discharge treatment of desulfurization wastewater in power plants, and solve the problem that the conventional treatment methods for desulfurization wastewater in power plants can only achieve discharge of wastewater up to standard, while evaporation and concentration are used. High energy consumption, serious equipment corrosion, high-concentration Cl-ion wastewater or NaCl solid mixed salt discharge will cause secondary pollution such as soil salinization and increased salt concentration in water

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for carrying out desalination and zero-discharge processing of power plant desulphurization wastewater by adopting electrodialysis technology

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0028] Example 1 Simulation of Power Plant Desulfurization Wastewater Electrodialysis Treatment

[0029] Electrodialysis technology was used to treat simulated power plant flue gas desulfurization wastewater, and the effects of different initial Cl- ions in concentrated water and fresh water on desalination rate, energy consumption and membrane stack voltage were investigated. Studies have shown that when the initial concentration of Cl- in fresh water is 1000, 5000, 10000 and 20000 mg / L, and the concentration of concentrated water is controlled at 20000 mg / L, the content of Cl- ions in fresh water after 150 minutes under constant pressure conditions can be reduced. However, when the concentration of Cl- ions in concentrated water is high, the removal rate of Cl- ions decreases, which is speculated to be caused by the reverse diffusion of Cl- ions in concentrated water; the current efficiency at different initial concentrations of fresh water They all show that the pre-desalin...

Embodiment 2

[0030] Example 2 Electrodialysis Desalination of Power Plant Flue Gas Desulfurization Wastewater

[0031] Such as figure 1 As shown, the flue gas desulfurization wastewater of power plants is pretreated by neutralization, precipitation, coagulation, filtration, etc., that is, by adding Ca(OH) 2 , desulfurizer and coagulant, etc., to remove COD, heavy metals, F-ions, and insoluble particles such as gypsum, silicon dioxide, iron and aluminum hydroxides in wastewater, and the obtained clarified liquid can meet the needs of subsequent membrane systems. Water requirements; desulfurization wastewater is pretreated and then treated by nanofiltration to obtain a large amount of Cl - ionized nanofiltration product water and removal of Cl - Ionic nanofiltration concentrated water; containing a lot of Cl - The ionized nanofiltration fresh water is further treated by multi-stage countercurrent reverse electrode electrodialysis technology to obtain fresh water with a Cl- ion concentrati...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention relates to a method for carrying out desalination and zero-discharge processing of power plant desulphurization wastewater by adopting an electrodialysis technology. The method comprises the following steps: neutralizing, precipitating, coagulating and filtering the power plant desulphurization wastewater and removing CODs (Chemical Oxygen Demands), heavy metals, F-ions, gypsum, silicon dioxide, hydroxide of iron and aluminum and other insoluble particles in waste water; separating C1-ions and other monovalent ions in clear liquid from SO3<2->, SO4<2-> and other divalent ions through nanofiltration; desalinating and concentrating water produced by the nanofiltration by adopting a multistage countercurrent reverse electrodialysis method. The method has the advantages that the concentration of the Cl-ions in nanofiltration concentrated water and electrodialysis freshwater generated by the method is lower, and the nanofiltration concentrated water and the electrodialysis freshwater can be returned for flue gas desulfurization; the content of NaCl in a small amount of electrodialysis concentrated water produced reaches above 12 percent, the bivalent ions and other impurities are removed by nanofiltration, and the electrodialysis concentrated water is further evaporated and concentrated, so that chlorine-alkali industry electrolytes and NaCl salt can be obtained. Through the method, the zero-discharge treatment and the resource utilization of the desulfurization wastewater can be realized.

Description

technical field [0001] The invention relates to the field of power plant desulfurization wastewater treatment technology, in particular, the invention relates to a method for treating power plant desulfurization wastewater using electrodialysis technology to achieve zero discharge and resource utilization. Background technique [0002] Limestone-gypsum wet flue gas desulfurization technology is currently the most widely used flue gas desulfurization technology. During the continuous operation of the desulfurization system, the slurry in the absorption tower continuously accumulates heavy metal elements, suspended solids and Cl - Such harmful substances, if not treated in time, will cause serious environmental pollution and equipment damage, and a part of desulfurization wastewater needs to be discharged regularly for treatment. For example, the joint action of F- and aluminum in the slurry has a shielding effect on the dissolution of the desulfurization absorbent limestone,...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C02F9/10C02F1/469C02F103/18
CPCY02A20/124
Inventor 石绍渊曹宏斌李玉平盛宇星
Owner INST OF PROCESS ENG CHINESE ACAD OF SCI
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap