Water Treatment FAQ: RO Systems, UF Systems, Wastewater Treatment and BOKAWATER Solutions

1. What is BOKAWATER?

BOKAWATER is a professional water treatment solutions provider from China, focused on industrial water treatment systems, wastewater treatment equipment, membrane systems and water treatment spare parts.

We provide one-stop solutions including reverse osmosis systems, ultrafiltration systems, nanofiltration systems, MBR wastewater treatment systems, DAF dissolved air flotation units, AOP advanced oxidation systems, MBBR biological treatment systems, integrated sewage treatment equipment, filter media, pressure vessels, FRP tanks, cartridges, pumps, valves and other water treatment components.

2. What products does BOKAWATER supply?

BOKAWATER supplies RO reverse osmosis systems, UF ultrafiltration systems, NF nanofiltration systems, seawater desalination systems, brackish water RO systems, MBR membrane bioreactor systems, DAF systems, MBBR systems, AOP systems, integrated sewage treatment systems, filtration systems, FRP tanks, pressure vessels, RO membranes, UF membranes, cartridge filters, pumps, valves, dosing systems, UV sterilizers and water treatment chemicals.

3. What industries can BOKAWATER serve?

BOKAWATER provides water treatment and wastewater treatment solutions for food and beverage, fruit and vegetable processing, bottled water, dairy, textile, printing and dyeing, electroplating, electronics, pharmaceutical, chemical, mining, oil and gas, landfill leachate, hotel wastewater, residential sewage, municipal wastewater, agriculture, power plants and industrial parks.

4. Does BOKAWATER provide customized water treatment systems?

Yes. BOKAWATER can design customized water treatment systems according to raw water quality, treated water requirements, flow capacity, installation space, power supply, automation requirements and local discharge standards.

Common customized systems include industrial RO systems, seawater desalination systems, containerized RO systems, UF pretreatment systems, MBR sewage treatment plants, food wastewater treatment systems, landfill leachate treatment systems, electroplating wastewater treatment systems and integrated wastewater treatment equipment.

5. What information is needed for a quotation?

To provide an accurate quotation, BOKAWATER usually needs the raw water source, treatment capacity, water analysis report, required treated water quality, discharge standard, project location, power supply, installation space and automation requirements.

For wastewater treatment projects, it is better to provide industry type, production process, daily wastewater volume, COD, BOD, TSS, oil, ammonia nitrogen, pH and target discharge or reuse standard.

6. What is a reverse osmosis system?

A reverse osmosis system, also called an RO system, is a pressure-driven membrane filtration system that removes dissolved salts, minerals, particles, bacteria and many organic impurities from water.

RO systems are widely used for industrial pure water, drinking water, boiler feed water, seawater desalination, brackish water treatment, process water and water reuse projects.

7. What is the difference between RO, UF and NF?

RO, UF and NF are all membrane separation technologies, but they remove different types of contaminants.

• UF ultrafiltration mainly removes suspended solids, colloids, bacteria, microorganisms and turbidity.
• NF nanofiltration removes hardness, color, divalent ions, some organic matter and partial dissolved salts.
• RO reverse osmosis removes most dissolved salts and produces high-purity water.

In simple terms, UF removes particles, NF removes hardness and selected salts, and RO removes most dissolved salts.

8. When should I choose UF instead of RO?

UF is suitable when the main problem is turbidity, suspended solids, bacteria, colloids or SDI reduction.

UF is often used as pretreatment before RO, especially for surface water, well water, wastewater reuse pretreatment, beverage process filtration and membrane protection.

UF cannot remove dissolved salts like RO. If the target is to reduce TDS or produce desalinated water, RO is usually required.

9. Can UF reduce SDI before RO?

Yes. Ultrafiltration is one of the most effective pretreatment methods for reducing SDI before RO systems.

Traditional pretreatment such as multimedia filters, manganese sand filters and activated carbon filters can reduce suspended solids and some organic matter, but UF provides more stable removal of fine particles, colloids and microorganisms.

10. What is the typical process for an industrial RO system?

A typical industrial RO system may include raw water tank, raw water pump, multimedia filter, activated carbon filter, softener or antiscalant dosing system, security filter, high-pressure pump, RO membrane system, pressure vessels, flow meters, conductivity meters, control panel, flushing system and CIP cleaning system.

11. What is the difference between single-pass RO and double-pass RO?

Single-pass RO means the water passes through one RO membrane system. It is suitable for many standard industrial and drinking water applications.

Double-pass RO means the permeate from the first RO system is treated again by a second RO system. It is used when higher purity water is required, such as electronics, pharmaceutical, boiler feed water, laboratory water and high-purity industrial applications.

12. How can I improve RO permeate water quality?

RO permeate quality can be improved by better pretreatment, correct membrane selection, double-pass RO design, proper operating pressure, suitable recovery rate, antiscalant dosing, pH adjustment and regular membrane cleaning.

13. Why does RO membrane fouling happen?

RO membrane fouling can be caused by suspended solids, colloids, organic matter, microorganisms, iron, manganese, hardness scaling, silica scaling, oil, chlorine damage or poor pretreatment.

To reduce membrane fouling, the system should have suitable pretreatment, SDI control, antiscalant dosing, cartridge filtration, regular flushing and CIP cleaning.

14. How often should RO membranes be cleaned?

RO membranes should be cleaned when there is a clear drop in permeate flow, an increase in differential pressure or a decline in permeate quality.

A common rule is to consider cleaning when normalized permeate flow decreases by about 10 to 15 percent, salt passage increases or pressure difference rises significantly.

15. Does BOKAWATER provide CIP cleaning systems?

Yes. BOKAWATER can provide CIP cleaning systems for RO, UF, NF and MBR membrane systems. A CIP system usually includes cleaning tank, cleaning pump, cartridge filter, valves, pipes, flow meter, heater if required and control system.

16. What is an MBR wastewater treatment system?

MBR means membrane bioreactor. It combines biological treatment with membrane separation. The biological process removes organic pollutants, while the membrane separates clean water from sludge and suspended solids.

MBR systems are widely used for domestic sewage, hotel wastewater, industrial park wastewater, food wastewater, hospital wastewater and wastewater reuse projects.

17. What is DAF in wastewater treatment?

DAF means dissolved air flotation. It is a wastewater treatment process that uses fine air bubbles to float oil, grease, suspended solids and flocs to the water surface for removal.

DAF is widely used in food processing wastewater, slaughterhouse wastewater, dairy wastewater, oil-containing wastewater, printing and dyeing wastewater and industrial pretreatment.

18. What is AOP advanced oxidation?

AOP means advanced oxidation process. It uses strong oxidation reactions to break down difficult organic pollutants, color, odor and refractory COD.

Common AOP technologies include ozone oxidation, UV oxidation, Fenton reaction, catalytic oxidation and combined oxidation systems.

19. What is MBBR wastewater treatment?

MBBR means moving bed biofilm reactor. It uses suspended biofilm carriers inside the tank to provide a large surface area for microorganisms.

MBBR can improve biological treatment efficiency and is suitable for COD, BOD, ammonia nitrogen and organic pollutant removal.

20. Can BOKAWATER provide integrated sewage treatment equipment?

Yes. BOKAWATER can provide integrated sewage treatment equipment for domestic wastewater, hotel wastewater, factory sewage, residential communities, schools, hospitals, camps and small municipal projects.

Common processes include A/O, A²/O, MBBR, MBR, sedimentation, disinfection and sludge treatment.

21. What is the typical process for wastewater treatment?

A typical wastewater treatment process may include screening, oil separation, equalization tank, pH adjustment, coagulation and flocculation, DAF, anaerobic treatment, aerobic treatment, MBBR, MBR, sedimentation, filtration, disinfection, sludge dewatering and advanced treatment.

22. Can RO treat wastewater?

Yes. RO can be used for advanced wastewater treatment and water reuse, but it normally requires proper pretreatment.

For wastewater reuse projects, common pretreatment before RO includes DAF, biological treatment, MBR, UF, activated carbon, cartridge filter and chemical dosing.

23. Can BOKAWATER design wastewater reuse systems?

Yes. BOKAWATER can design wastewater reuse systems for industrial water recycling, process water reuse, cooling tower makeup water, irrigation reuse, flushing water and production water recovery.

24. Can BOKAWATER treat high COD wastewater?

Yes. BOKAWATER can design treatment systems for high COD wastewater. Depending on the wastewater type, the process may include equalization, pH adjustment, coagulation, DAF, anaerobic treatment, aerobic treatment, MBBR, MBR, AOP, activated carbon, RO or evaporation.

25. Can BOKAWATER treat heavy metal wastewater?

Yes. BOKAWATER can provide treatment solutions for heavy metal wastewater, including electroplating wastewater, mining wastewater, metal finishing wastewater and industrial rinse water.

Common treatment methods include pH adjustment, chemical precipitation, coagulation, sedimentation, filtration, ion exchange, membrane separation and sludge dewatering.

26. What is seawater desalination?

Seawater desalination is the process of removing salt from seawater to produce fresh water. The most common technology is seawater reverse osmosis, also called SWRO.

27. Can BOKAWATER provide seawater desalination systems?

Yes. BOKAWATER can provide seawater desalination systems with pretreatment, high-pressure RO system, energy recovery options, chemical dosing, control system and post-treatment.

Systems can be skid-mounted or containerized according to project requirements.

28. What is brackish water RO?

Brackish water RO is used to treat water with moderate salinity, such as well water, groundwater, lake water or industrial process water with high TDS.

Compared with seawater RO, brackish water RO usually operates at lower pressure and lower energy consumption.

29. What is SDI and why is it important?

SDI means silt density index. It measures the fouling tendency of water before RO membranes.

High SDI means the water contains more particles, colloids or fouling substances, which can block RO membranes. UF pretreatment is often used when traditional filters cannot reduce SDI effectively.

30. What is TDS?

TDS means total dissolved solids. It represents the amount of dissolved salts and minerals in water. RO systems are commonly used to reduce TDS and produce low-conductivity water.

31. What is COD in wastewater treatment?

COD means chemical oxygen demand. It indicates the amount of oxidizable organic and inorganic substances in wastewater.

COD removal may require coagulation, DAF, biological treatment, MBR, AOP, activated carbon, RO or evaporation, depending on wastewater characteristics.

32. What is BOD in wastewater treatment?

BOD means biochemical oxygen demand. It measures the amount of oxygen microorganisms need to degrade organic matter in wastewater.

Biological treatment such as aerobic treatment, anaerobic treatment, MBBR and MBR is commonly used to reduce BOD.

33. What is TSS?

TSS means total suspended solids. It includes suspended particles in wastewater or raw water.

TSS can be removed by sedimentation, coagulation, DAF, multimedia filtration, UF and MBR.

34. Can BOKAWATER provide zero liquid discharge systems?

Yes. BOKAWATER can support ZLD, or zero liquid discharge, projects.

A ZLD system may include pretreatment, biological treatment, UF, RO, high-pressure RO, evaporation, crystallization and sludge or salt handling.

35. What is an MVR evaporator?

MVR means mechanical vapor recompression. It is an evaporation technology that reuses secondary steam to reduce energy consumption.

MVR evaporators are used for high-salt wastewater, concentration, crystallization, mother liquor treatment, landfill leachate, chemical wastewater and zero liquid discharge.

36. Can BOKAWATER provide spare parts for water treatment systems?

Yes. BOKAWATER supplies RO membranes, UF membranes, membrane housings, pressure vessels, cartridge filters, filter housings, FRP tanks, control valves, pumps, dosing pumps, flow meters, conductivity meters, UV sterilizers, filter media and fittings.

37. Does BOKAWATER supply RO membranes and pressure vessels?

Yes. BOKAWATER can supply RO membranes, NF membranes, UF membranes and pressure vessels. Common pressure vessel specifications include 4040 and 8040 membrane housings.

38. Does BOKAWATER provide filter media?

Yes. BOKAWATER supplies water treatment filter media such as quartz sand, activated carbon, manganese sand, anthracite, resin, ceramic media and other filtration materials.

39. Does BOKAWATER provide OEM and ODM services?

Yes. BOKAWATER provides OEM and ODM services for water treatment equipment, membrane systems and spare parts.

We can support customers with private label products, customized system design, skid-mounted equipment, branded packaging, technical drawings, operation manuals and project support.

40. Can BOKAWATER support EPC or engineering companies?

Yes. BOKAWATER can support EPC contractors and engineering companies with equipment supply, technical selection, process design, drawings, component matching, system integration, factory testing and after-sales service.

41. Can BOKAWATER cooperate with distributors?

Yes. BOKAWATER welcomes cooperation with local distributors, agents and water treatment companies.

We can provide product supply, technical support, OEM branding, marketing materials, spare parts, quotation support and project selection assistance.

42. Can BOKAWATER provide private label products?

Yes. BOKAWATER can provide private label and OEM branding services for selected products, including customized logo, product label, packaging, manuals and marketing documents.

43. Can BOKAWATER provide containerized water treatment systems?

Yes. BOKAWATER can provide containerized RO systems, containerized seawater desalination systems, containerized UF systems and containerized wastewater treatment plants.

Containerized systems are suitable for remote areas, islands, construction camps, mining sites, emergency water supply, mobile water treatment and overseas projects.

44. What is the advantage of skid-mounted water treatment equipment?

Skid-mounted systems are pre-assembled on a frame before delivery. The advantages include compact structure, easier installation, shorter commissioning time, better quality control and reduced on-site construction work.

45. What is the advantage of automatic control systems?

Automatic control systems improve operation stability, reduce manual work and protect equipment. A water treatment control system can monitor pressure, flow, conductivity, liquid level, pump status, valve status and alarms.

46. What is the delivery time for BOKAWATER equipment?

Delivery time depends on product type, system capacity, customization level and order quantity. Standard spare parts can usually be prepared faster. Customized RO systems, UF systems, MBR systems or containerized systems need more time for design, production, assembly and testing.

47. Can BOKAWATER ship equipment overseas?

Yes. BOKAWATER can ship water treatment equipment and spare parts to overseas markets. We can arrange export packaging, wooden cases, pallet packaging, container loading and shipping documents according to customer requirements.

48. Does BOKAWATER provide installation guidance?

Yes. BOKAWATER can provide installation guidance through drawings, manuals, online technical support, videos and remote communication.

49. Does BOKAWATER provide operation manuals?

Yes. BOKAWATER can provide operation manuals, equipment drawings, electrical drawings, process flow diagrams, equipment layout drawings and maintenance instructions when required.

50. Does BOKAWATER test equipment before delivery?

For customized systems, BOKAWATER can conduct factory inspection and testing before delivery, including pump testing, valve checking, control panel testing, pipeline inspection, pressure testing, electrical testing and system operation simulation.

51. Can BOKAWATER provide remote technical support?

Yes. BOKAWATER can provide remote technical support through email, video call, photos, operation data and online communication.

52. Does BOKAWATER provide solutions for food and beverage wastewater?

Yes. BOKAWATER can provide food and beverage wastewater treatment systems. Food wastewater often contains high COD, BOD, oil, grease, suspended solids and organic matter.

Common processes include screening, oil separation, equalization, pH adjustment, coagulation, DAF, anaerobic treatment, aerobic treatment, MBR and disinfection.

53. Does BOKAWATER provide bottled water treatment systems?

Yes. BOKAWATER can provide water treatment systems for bottled water production, including pretreatment, activated carbon filter, softener, RO system, UV sterilizer, ozone generator, pure water tank and filling line connection.

54. Does BOKAWATER provide boiler feed water treatment?

Yes. BOKAWATER can provide boiler feed water treatment systems. Common technologies include softening, RO, double-pass RO, EDI, mixed bed ion exchange and chemical dosing.

55. Does BOKAWATER provide pharmaceutical water treatment systems?

BOKAWATER can provide industrial pure water and high-purity water treatment solutions for pharmaceutical-related applications. Depending on the required standard, the system may include pretreatment, RO, double-pass RO, EDI, UV, ozone, ultrafiltration and sanitary piping.

56. Does BOKAWATER provide electronics ultrapure water systems?

Yes. BOKAWATER can provide high-purity water treatment systems for electronics, semiconductor-related supporting processes, PCB, electroplating and precision cleaning.

57. Does BOKAWATER provide solutions for landfill leachate?

Yes. BOKAWATER can provide landfill leachate treatment solutions. Common treatment technologies include biological treatment, MBR, NF, RO, STRO, DTRO, AOP and evaporation.

58. How do I choose the right water treatment system?

To choose the right water treatment system, you should first define the water source, treatment target, required capacity and water quality standard.

For high TDS water, RO may be required. For high turbidity water, UF or filtration may be required. For domestic sewage, MBR or biological treatment may be suitable. For food wastewater, DAF plus biological treatment is often used. For high-salt wastewater, RO, evaporation or ZLD may be needed.

59. What are common problems in RO systems?

Common RO problems include low permeate flow, high permeate conductivity, high differential pressure, frequent membrane fouling, scaling, pump failure, valve leakage, pressure instability and control system alarms.

60. What are common problems in wastewater treatment systems?

Common wastewater treatment problems include high COD in effluent, high ammonia nitrogen, sludge bulking, odor, unstable pH, poor DAF flotation, MBR membrane fouling, low dissolved oxygen and excessive sludge.

61. Can BOKAWATER help upgrade an existing water treatment plant?

Yes. BOKAWATER can help upgrade existing water treatment or wastewater treatment systems by adding UF pretreatment, replacing RO membranes, adding MBR, improving DAF performance, adding AOP, adding automation, increasing capacity or improving effluent quality.

62. What is the lifespan of RO membranes?

RO membrane lifespan depends on raw water quality, pretreatment, operating pressure, recovery rate, chemical cleaning, chlorine control and maintenance. In well-operated industrial systems, RO membranes can often be used for several years.

63. What is the lifespan of UF membranes?

UF membrane lifespan depends on water quality, filtration flux, backwash, chemical cleaning, operating pressure and maintenance. Correct operation, regular backwash and proper chemical cleaning can help maintain stable UF performance.