What are the advantages and disadvantages of different filter elements in environmental protection water treatment projects?
According to the most commonly used filter material of environmental protection water treatment project, I will sort it out for you directly: advantages, disadvantages, applicable scenarios and inapplicable scenarios, which are clear and good for comparison and convenient for selection.
I. PP (polypropylene) meltblown/folded filter element
The most commonly used and cost-effective universal filter element
advantage
Low price and strong versatility.
Wide range of acid and alkali resistance (pH 1–13)
No adhesive, no secondary pollution.
Melt-blown deep filtration, good pollution-holding capacity.
Folding money has large flow and low pressure.
disadvantage
Not resistant to high temperature (generally ≤60℃)
Reusable and disposable consumables cannot be cleaned.
Anti-fouling ability is average, and many impurities are easy to block.
Average strength, easy to deform under high pressure difference.
Application: municipal water/well water pretreatment, RO security filtration, circulating water and reclaimed water reuse pre-treatment.
Not applicable: high temperature water, strong organic solvent and high solid content for long-term operation.
Second, PES (polyethersulfone) filter element
High-precision water purification and sterilization are commonly used
advantage
The accuracy is stable (0.05–1μ m)
Good hydrophilicity, large flow and small pressure difference.
The temperature resistance is higher than that of PP (≤80℃)
Good biological safety, suitable for food/medicine/pure water.
disadvantage
The price is higher than PP
Not tolerant to strong oxidants (ozone, high concentration of residual chlorine)
Non-washable reuse
Application: RO terminal, ultrafiltration post-treatment, laboratory pure water and sterile water pretreatment.
Not applicable: direct filtration of raw water with strong oxidant and high pollution.
Iii. PTFE (polytetrafluoroethylene) filter element
"All-round" high-end filter element with the strongest chemical resistance
advantage
Resistant to strong acid, strong alkali, strong oxidant and organic solvent.
High temperature resistance (steam sterilization at 121℃)
0.22μm can achieve true sterilization level.
Not easy to age, long service life
disadvantage
Expensive
It is hydrophobic and needs hydrophilic treatment.
Non-backwashing multiplexing
Application: chemical wastewater, strongly corrosive liquid, medical sterile water, ultra-pure water terminal, acid-base liquid filtration.
Not applicable: ordinary municipal water (the cost is too high)
Iv. Nylon/PA filter element
High toughness and good hydrophilicity.
advantage
High strength, not easy to break.
Good hydrophilicity and quick start-up
Uniform precision, suitable for sterilization (0.22μm)
Resistant to most solvents
disadvantage
Alkali resistance is average
Not resistant to high temperature (≤70℃)
Easy to hydrolyze, long-term life in hot water decreased.
Application: food and beverage, electronic pure water, liquid medicine filtration, sterilization filtration.
Not applicable: strong alkaline water, high temperature water and high SS sewage.
V. Activated carbon filter element (coal quality/coconut shell)
Essential adsorption materials for water treatment
advantage
Strongly remove residual chlorine, abnormal color, peculiar smell and small molecular organic matter.
Reduce COD and partially decolorize
Improve the taste of effluent.
disadvantage
Do not remove suspended matter, salt and heavy metals (unless modified)
It is easy to breed bacteria and needs pre-filtration.
The adsorption saturation is fast, so it needs to be replaced regularly.
The pressure drop gradually increases with use.
Application: advanced treatment of tap water, RO post-treatment, deodorization and decoloration of reclaimed water reuse.
Not applicable: direct filtration of high turbidity water, high temperature water, pursuit of desalination/sterilization.
Six, stainless steel/titanium sintered filter element
Industrial filter element capable of cleaning and resisting high temperature and high pressure.
advantage
Can be repeatedly cleaned, blown back and reused, and has extremely long service life.
High temperature resistance (up to several hundred degrees) and high pressure resistance
Extremely high strength, not easy to break.
Acid and alkali resistance, oil resistance and organic solvent resistance.
disadvantage
High unit price
The accuracy is not high (generally ≥1μm)
The interception effect on colloid and microorganism is poor.
Application: high-temperature wastewater, oily wastewater, circulating water, backwashable system, and coarse filtration of chemical stock solution.
Not applicable: sterilization, colloid removal, ultra-pure water, pursuing low-cost scenarios.
Seven, ceramic filter
Scrubble and durable type
advantage
Repeated brushing, long service life.
Acid and alkali resistance and pollution resistance
High mechanical strength
disadvantage
Small flow
Limited accuracy
Brittle, afraid of impact
Application: well water purification, small water purification equipment, decentralized water treatment in rural areas.
Not applicable: large flow engineering, high turbidity sewage.
Eight, glass fiber (glass fiber) filter
High-capacity, high-flow special purpose
advantage
The sewage capacity is extremely large, which is suitable for high SS water.
Large flow and low pressure
High temperature resistance (≤90℃)
disadvantage
Easy to lose fiber, which may cause secondary pollution.
Not washable
Accuracy control generally
Application: advanced treatment of circulating water and sewage in steel mills/power plants, pre-treatment and high turbidity raw water.
Not applicable: electronics, medicine, food and other scenes sensitive to precipitates.
