New high-performance RO & NF membrane homogeneous homopores nanoskeleton

Background:

At present, the RO/NF films on the market are all use non-woven PAN, PES, PSF coating + non-woven as the basic skeleton, then coated with a desalination functional layer on the surface,

the overall structure is 3 layers:

1. Bottom layer: PET non-woven , which is responsible for providing the support stability of the overall structure and the deformation resistance to high working pressure.

1.1 Acid resistance but not alkali resistance, easy to age, disintegrate, and have the risk of fiber shedding in a high-salt environment.

1.2 The pressure resistance and blasting performance restrict the upper limit of the working pressure of the RO.

1.3 Barely used in conventional freshwater RO, the performance and life can not meet the high-salt environment and target design performance requirements of seawater desalination SWRO.

1.4 The average pore size is >20um, tolerance is large, which seriously affects the thickness of the subsequent coating, the tolerance size, uniformity and porosity of the subsequent coating.

2. Middle layer: PAN, PES, PSF emulsion is coated on non-woven bone, and sub-micron transition pore size of 0.1-0.2um is obtained after filling.

2.1 The coating is thick, and it is easy to collapse, crack and fall off under high pressure. Affect RO service life.

2.2 The pore size is too large, and the desalination coating must be applied again to obtain an effective sub-nanometer pore size of 0.1-1.0nm to ensure the desalination accuracy.

2.3 The porosity of the coating is about 50%, and it will further decrease after the second coating.

3. Surface layer: pore size sieving + ionic group charged desalination functional layer.

3.1 Because of the large pore size of the transition coating, the tolerance of the pore size of the desalination layer of the second coating is >30%, and the porosity is <50%.

3.2 The superimposed double-layer coating is easy to collapse under high pressure, and easy to peel off with high salt infiltration.

3.3 The desalination rate and water yield are limited, the attenuation is fast, and the energy consumption is high.

Alternative advantages of new high-strength nanoframeworks:

* Homogeneous ultra-high molecular weight UPOF material, high strength (warp and weft >100MPa), can withstand higher pressure, and the deformation is very small.

* High stiffness, thickness is only 20-65um, more layers can be wound, and the total film area is larger.

* Homopores structure, basic pore size of 30-35nm, effective concentration of >90%, can omit the transition coating, directly coated with the desalination functional layer,

   you can obtain uniform sub-nano effective pore size, tolerance<20%, high desalination accuracy, the coating is not easy to fall off and collapse.

* Skeleton porosity 55-65%, about 55% after coating. High flow rate, long-term hydrophilic, slow attenuation.

* Able to withstand higher working pressure, under the premise of maintaining desalination accuracy, obtain ultra-high flow rate.

* The material is resistant to salt corrosion and microbial decomposition, not easy to age, and has a long service life.

* Compared with the traditional 3-layer structure, the RO2 layer structure has simple process, controllable parameters, and obvious alternative advantages in price and cost.

Contact consultation: Shenzhen Huahesheng Technology Co., Ltd. (website www.szhhstech.com, Whatsapp +8618675555716)