Treatment and reuse method for reverse osmosis concentrated water

Abstract

The invention discloses a treatment and reuse method for reverse osmosis concentrated water. The treatment and reuse method comprises the following steps: injecting the reverse osmosis concentrated water into a reaction device for chemical treatment and pH value increase, wherein the reaction device comprises a chemical reactor, and a medicament is added into the reaction device through a doser; separation of the chemically treated wastewater: injecting the chemically treated wastewater into a concentrator, and injecting concentrated water into a separation main machine through a booster pump; filtration of the separated wastewater: pressurizing the wastewater subjected to treatment of the separation main machine with a lift pump, pressurizing with a high-pressure pump after the lifted water passes through a filter, and injecting the pressurized water to a reverse osmosis main machine; reverse osmosis treatment of the filtered water: conducting reverse osmosis treatment on softened permeate liquid obtained after chemical treatment, separation and filtration with the reverse osmosis main machine, wherein the reverse osmosis treatment includes separation and desalination, and finally a purified water product for recycling and utilization is produced. As heavy metal ions, hardness ions such as calcium ions and magnesium ions, silicon, COD and other pollutants are removed before reverse osmosis treatment of the concentrated water, the concentrated water reverse osmosis main machine is protected; the consumption of medicaments is reduced; less sludge is generated.

Description

technical field [0001] The invention belongs to the technical field of waste water treatment, and in particular relates to a method for treating and reusing concentrated reverse osmosis water. Background technique [0002] Existing technologies for desulfurization wastewater treatment have the following deficiencies: [0003] Reverse osmosis technology has been widely used in the field of water desalination treatment with its stable desalination rate of 98%, but its recovery rate is only 70-80%, so that 20-30% of reverse osmosis concentrated water is discharged, causing water pollution. It is a very large waste of resources; and the reverse osmosis concentrated water contains high salt content and a large amount of calcium and magnesium scaling ions, heavy metal ions, silicon ions and other special substances. At this stage, the reverse osmosis concentrated water is basically discharged; Infiltration of concentrated water has become a trend in water treatment applications, ...

AI Technical Summary

Problems solved by technology

In China, the patent number is ZL200920115523.5, the name is "Reverse Osmosis Concentrated Water Reuse Device", and the Chinese Patent Number is ZL200820232440.X, the name is "A Membrane Filtration Device for Treating Reverse Osmosis Concentrated Water", and there are also Chinese patents No. ZL200820168798.0, titled "Reverse Osmosis Concentrated Water Recycling Device" and other existing technologies, in the related research on reverse osmosis concentrated water recycling, their common feature is: directly add scale inhibitor and reverse osmosis concentrated water For other chemical agents, the pH value is controlled to be less than 9, thereby inhibiting the precipitation of heavy metal ions and calcium and magnesium hardness ions on the surface of the concentrated water reverse osmosis membrane behind, so as to achieve the purpose of reusing reverse osmosis concentrated water; the disadvantages of the above-mentioned technical process are: Suppress and disperse heavy metal ions and hardness ions that may cause scaling by antiscalants and other chemicals; primary reverse osmosis concentrated water is high-salt water that has been concentrated 4 times from raw water, all heavy metal ions, calcium and magnesium hardness The concentration of ions, silicon, COD and other pollutants is already very high, which has already exceeded the saturation concentration product of each ion. The antiscalant is added to the first-stage reverse osmosis system to prevent the scale pollution from exceeding the saturation concentration product; now The above-mentioned process technology adds antiscalants to reverse osmosis concentrated water, and there are the following problems: first, excessive addition of antiscalants will cause the generation of other pollutants and cause secondary pollution; second, the ion concentration is too high, However, the antiscalant cannot achieve the purpose of antiscaling; third, it has no effect on COD removal; fourth, the recovery rate of the reverse osmosis system is low