CN-224226826-U - Treatment system for purifying high-salt wastewater

Abstract

The utility model relates to a treatment system for purifying high-salt wastewater, which is suitable for treating high-salt wastewater, in particular to desulfurization wastewater of coal-fired power plants and coal chemical wastewater. The method comprises the steps of combining high-efficiency flocculation, ozone catalysis and membrane distillation technologies, adding a self-made chitosan-based flocculant in a flocculation stage, removing suspended matters and heavy metal ions in wastewater by utilizing good adsorption performance and flocculation capacity of the self-made chitosan-based flocculant, adding a self-made ternary composite catalyst in an ozone catalysis stage, promoting ozone decomposition, further removing organic pollutants, and carrying out high-efficiency desalination and concentration by using a self-made anti-fouling and anti-wetting composite membrane in a membrane distillation stage, so that high-efficiency purification and recycling of high-salinity wastewater are finally achieved. The process can obviously improve the treatment effect of the wastewater, reduce the concentration of salt and harmful substances in the wastewater, reduce the operation cost and is suitable for treating large-scale industrial wastewater.

Inventors

• LIU ZHAOYANG
• QI LIQIANG
• WANG WEN

Assignees

• 南京市蓝天白云科技有限公司

Dates

Publication Date

20260512

Application Date

20250228

Claims (5)

1. 1. A treatment system for purifying high-salt wastewater is characterized by comprising the following key components of (1) a high-efficiency flocculation reaction component, an ozone catalytic reaction component, a membrane distillation component and a membrane separation component, wherein the high-efficiency flocculation reaction component is used for adding a chitosan-based flocculant and adjusting the pH value of wastewater to 6.5-7.5, (2) an Mn-Ce-Bi ternary composite catalyst is arranged in the ozone catalytic reaction component, the molar ratio of Mn, ce and Bi of the catalyst is 2:1:1, and the membrane distillation component adopts a composite membrane of PVDF-HEP and super-hydrophobic SiO 2 as a basic membrane; the outlet of the efficient flocculation reaction component is connected with the inlet of the ozone catalytic reaction component, and the outlet of the ozone catalytic reaction component is connected with the inlet of the membrane distillation component.
2. 2. The high-salinity wastewater purification treatment system according to claim 1, wherein the high-efficiency flocculation reaction assembly comprises a flocculation reaction device, a water sample collecting device and a circulating pump, and the high-salinity wastewater flows through the flocculation reaction device and the water sample collecting device in sequence and enters the ozone catalytic reaction assembly through the circulating pump during operation.
3. 3. The high-salt wastewater purification treatment system according to claim 1, wherein the ozone catalytic reaction assembly comprises an ozone generator, an ozone detector, an ozone catalytic reactor and a water quality detector, wherein ozone generated by the ozone generator enters the ozone catalytic reactor through the ozone detector, the ozone detector can control ozone flow, and the water quality detector is connected with the ozone catalytic reactor and is used for detecting water quality at regular time.
4. 4. The high-salinity wastewater purification treatment system according to claim 1, wherein the membrane distillation assembly comprises a feed side system, a flow control meter, a membrane distillation device, a permeate side system, a conductivity monitor, a water yield monitor and a circulating pump, water enters the membrane distillation device from the feed side system through the circulating pump and the flow control meter during operation, and purified water enters the water yield monitor from the permeate side system through the circulating pump.
5. 5. The treatment system for purifying high-salt wastewater according to claim 1, wherein the composite membrane is prepared by electrostatic spinning with PVDF-HEP and super-hydrophobic SiO 2 as spinning solutions, and the final composite membrane is obtained by electrospraying a chitosan flocculant.

Description

Treatment system for purifying high-salt wastewater Technical Field The invention relates to the technical field of coal chemical wastewater treatment, in particular to a preparation method of an anti-pollution and anti-humidity functional membrane for high-salt wastewater concentration and a pretreatment and membrane concentration process. Technical Field Along with the promotion of the industrialization progress, a large amount of wastewater generated in industries such as coal-fired power plants, coal chemical industry and the like becomes a serious environmental problem. In particular, in the treatment of desulfurization wastewater and coal chemical wastewater, the wastewater contains higher salt and organic pollutants, and the wastewater production amount in the novel coal chemical industry in China reaches 47.45 hundred million tons/year by 2023 years. The conventional treatment method is difficult to effectively remove harmful substances in the water, so that the treatment efficiency is low and the subsequent water quality is difficult to reach the standard. The traditional wastewater treatment method comprises a physical method, a chemical method and a biological method, but most of the traditional wastewater treatment methods have the problems of low treatment efficiency, high cost, incapability of meeting emission standards of treated water quality and the like, such as easy pollution of traditional membrane distillation, low ozone catalysis efficiency, less than 60 percent of heavy metal removal rate of the traditional flocculant and the like. Therefore, there is a need for a new wastewater treatment process that is efficient, low cost, and has a high treatment effect. The coal chemical industry strong brine has various sources, including strong brine produced by the preparation of desalted water, the repeated use of circulating water, the water of a boiler and the addition of agents in the treatment of reuse water. The strong brine source can also contain a certain salt content in addition to a small amount of water enriched in the process, for example, in the coal chemical industry project, yellow river water is used as fresh water to supplement more than 50% of the salt content of the whole project system, and the salt content generated by chemical agents added in the whole production process and the water system accounts for more than one third of the total salt content. Therefore, even though a limited water saving effect can be achieved by determining reasonable circulation times and dosing modes, more difficult-to-treat strong brine accounting for about 15% -30% of the volume fraction is still produced finally. Disclosure of Invention In order to overcome the defects of the prior art, the utility model provides a treatment system design for purifying high-salt wastewater. The process is used for remarkably improving the treatment efficiency of the high-salt wastewater through the three-stage combined treatment of flocculation, ozone catalysis and membrane distillation, and is particularly suitable for the high-efficiency treatment of desulfurization wastewater and coal chemical wastewater of coal-fired power plants. The technical scheme of the utility model comprises the following key steps: 1. And in the flocculation stage, chitosan is dissolved in 1% acetic acid solution, cyanuric acid is added, the reaction is carried out for 6 hours at 60 ℃ under the protection of nitrogen, and the product is subjected to ethanol precipitation, drying and crushing to 100 meshes to obtain the chitosan-based flocculant. The self-made chitosan-based flocculant is added into the wastewater, and the chitosan-based flocculant has excellent flocculation capacity and can efficiently remove suspended particles and partial soluble organic matters in the wastewater. The flocculant not only can remove most suspended particles, but also can create better conditions for the subsequent treatment process by improving the water quality. The mass ratio of chitosan to cyanuric acid can be between 2:1 and 3:1, but when the mass ratio is 3:1, the flocculation effect is optimal, the suspended matter removal rate reaches 95%, and the heavy metal (As, hg) removal rate reaches 90%.2. Ozone catalysis stage: in the wastewater treatment process, the addition of a specific reagent can obviously improve the decomposition efficiency of ozone so as to accelerate the oxidative decomposition of organic pollutants, for example, calcium ions or barium ions are added into the wastewater, the hydroxyl radical trapping agent generated in the alkaline catalytic ozone advanced oxidation process can be removed so as to improve the utilization efficiency of ozone, in addition, the ozone catalytic oxidation method also shows good effect when treating COD in high salinity concentrated water, the device is stable in operation, the COD index of the effluent is qualified, the mole ratio of Mn, ce and Bi can be between 1:1 and 3:2:1, but the catalyst