Immersion ultrafiltration MUF

The enhanced polyvinylidene fluoride (PVDF) hollow fiber ultrafiltration membrane is lined with a suction pump (production pump) to form negative pressure in the hollow fiber membrane. Due to the negative pressure, the water to be treated enters the internal channel of the hollow fiber through the micropores of the ultrafiltration membrane, and then collects into the production pipe and enters the clean water pool through the suction pump. To achieve the purpose of solid-liquid separation of mixed liquid to obtain purified water treatment. The treated water quality is excellent and stable, which can not only avoid the problem of suspended matter leakage in the traditional process of sedimentation separation, but also remove microorganisms such as Escherichia coli and cryptosporidium, and the water produced by the membrane system can be reused directly or after adding a small amount of disinfectants as waste water or water for similar purposes.

Wu's printing and dyeing adopts a unique high strength, high hydrophilicity, anti-pollution homogeneous and heterogeneous enhanced immersion ultrafiltration membrane, with the following main characteristics:

1, small membrane aperture and uniform distribution, high quality water production;

2, the membrane has good hydrophilicity and strong anti-pollution performance;

3, filter pressure is small, save energy;

4, good resistance, easy to clean and restore;

5, high mechanical strength, not easy to peel and break the wire.

ozone

Engineering design to treat printing and dyeing wastewater 5000 cubic meters/day, using heterogeneous catalytic ozone oxidation technology. This technology uses ozone as oxidizing agent, under the action of carbon-based catalyst, oxidation degrades organic matter through free radical reaction, mainly removes dyes and additives, and then reduces COD concentration, eliminates color and odor in water, and meets the requirements of deep treatment of printing and dyeing wastewater. The technology is supported by Zhejiang University, supported by the National Key Research and Development Plan (2016YFB0301802), and the technical invention number (201711259905).

First stage reverse osmosis (RO)

Reverse osmosis, also known as reverse osmosis, is a membrane separation operation that uses the pressure difference as a driving force to separate the solvent from the solution. Pressure is applied to the material liquid on one side of the membrane, and when the pressure exceeds its osmotic pressure, the solvent will reverse permeate against the direction of natural penetration. Thus, the solvent is penetrated on the low pressure side of the membrane, that is, the osmotic fluid; The high pressure side obtained a concentrated solution, that is, a concentrated solution. The reverse osmosis membrane can trap various inorganic ions, colloidal substances and macromolecular solutes in the water, so as to obtain net water.

Wu's Printing and dyeing Co., Ltd. cooperated with Nitto Denko to screen and develop anti-pollution reverse osmosis membrane suitable for zero discharge process of printing and dyeing wastewater, separating purified water from wastewater reaches more than 70%. This type of reverse osmosis membrane has the following main characteristics:

1, with a neutral, hydrophilic film surface;

2, high desalting rate and high pressure resistance;

3, widely used in printing and dyeing cationic, anionic, amphoteric surfactants, can effectively reduce membrane pollution.

Secondary nanofiltration (NF)

Nanofiltration is a pressure-driven membrane separation process between reverse osmosis and ultrafiltration, and the pore size of nanofiltration membranes ranges from a few nanometers. Nanofiltration membrane is a charged membrane, which can carry out electrical adsorption. Under the same water quality and environment, the pressure required by nanofiltration membrane is less than that required by reverse osmosis membrane. The separation mechanism of nanofiltration membrane is the coexistence of sieving and dissolution diffusion, and has charge repulsion effect, which can effectively remove divalent and polyvalent ions and remove all kinds of substances with molecular weight greater than 200.

Wu's Printing and dyeing Co., Ltd. cooperated with Nitto Denko to screen and develop the anti-pollution nanofiltration membrane suitable for the zero-discharge process of printing and dyeing wastewater, which continued to separate and purify the primary reverse osmosis concentrated water, and the total recovery water rate reached 95%

The sodium chloride and sodium sulfate in the wastewater are separated, and the sodium sulfate concentration can reach more than 10%. This type of nanofiltration membrane has the following main characteristics:

1, specifically for sulfate removal, especially conducive to the separation of sulfate and chloride ions;

2, hardness and organic matter removal effect is good;

3, effectively reduce pollution blockage.

Three-stage Ultra-High Pressure Reverse osmosis (UHPRO)

Ultra-high pressure reverse osmosis is the use of stronger materials for reverse osmosis, and its high operating pressure reaches 12.4MPa, far more than the traditional 8.27 MPa, which is more conducive to the concentration of pollutants and salt.

Wu's Printing and Dyeing Co., Ltd. cooperated with Nitto Denko to screen and develop anti-pollution UHP reverse osmosis membrane suitable for zero discharge process of printing and dyeing wastewater. The sodium chloride separated by secondary nanofiltration was concentrated to more than 10%.

1, more than 50% concentration of traditional film;

2, stronger chemical cleaning tolerance;

3, stronger anti-pollution performance.

MVR evaporative crystallization

MVR evaporation method is the abbreviation of steam mechanical supercharging distillation and concentration system, which is composed of turbo-engine supercharging principle and special fluid design. This process system will make the secondary water vapor generated by heating in the closed container be compressed and pressurized to 107 degrees Celsius when passing through the steam compressor. This added steam can be used as a regenerative heat source and recycled for the continuous distillation of raw water, and in the process of circulating heat transfer, the pressurized steam itself can be rapidly cooled or condensed until it becomes clean and pure water, and its residual heat can be used in the process of discharging the net condensate water to implement heat exchange for the incoming raw water.

The main features of MVR system are:

1, energy saving: no waste heat steam emissions, energy saving effect is very significant, equivalent to 10 effect evaporator.

2, environmental protection: the equipment can not need steam, no boiler, no need to burn coal, no need for cooling water, as long as there is electricity, you can use mechanical compression evaporator. Thus, the emission of CO2 and S02 is reduced, the emission of dust and solid waste is reduced, and pollution is reduced.

3, low operating cost: due to the good energy saving effect, the operating cost of the entire evaporator is also greatly reduced, as long as the traditional evaporator one-third to one-half.

4, small footprint: MVR evaporator because of the use of a compressor to cycle the use of secondary steam, improve energy efficiency, so more compact than the traditional evaporator.