| 01 | Low-salinity tertiary RO | Municipal secondary effluent after biological treatment | 500–2,000 | 70–85% | 20–150 | 10–1,000 m³/day | Fine screening, multimedia or membrane filtration, cartridge filtration, dechlorination | Cooling makeup, toilet flushing, irrigation, process water | Local reclaimed-water limits; microbial disinfection; nutrient and turbidity requirements | A cost-effective option when biological treatment already controls organic loading. |
| 02 | Industrial process-water RO | Food, beverage, pharmaceutical, and general manufacturing wastewater | 1,000–5,000 | 65–80% | 30–300 | 5–500 m³/day | Oil separation where required, coagulation, clarification, cartridge filtration, antiscalant | Wash water, utility water, cooling circuits, non-product contact use | Discharge permit, sector-specific contaminants, chemical oxygen demand, oil, and metals | Feed variability should be confirmed through composite sampling rather than a single grab sample. |
| 03 | High-recovery two-pass RO | Treated industrial effluent requiring low conductivity water | 1,000–4,000 | 80–90% overall | 5–80 | 10–1,000 m³/day | Advanced filtration, precise pH control, antiscalant, dechlorination, degassing as needed | Boiler makeup after polishing, high-grade process water, rinse water | Conductivity, silica, boron, hardness, microbiological control, and end-use specifications | Higher recovery reduces reject volume but increases scaling risk and control complexity. |
| 04 | Textile wastewater RO | Dyeing, printing, washing, and finishing effluent | 1,500–8,000 | 60–80% | 50–500 | 10–500 m³/day | Color removal, biological treatment, ultrafiltration, cartridge filters, antiscalant | Dye-bath reuse, washing, cooling, and non-potable plant applications | Color, surfactants, COD, toxicity, salinity, and local industrial discharge limits | Membrane fouling control is critical because dyes, polymers, and surfactants can accumulate quickly. |
| 05 | Landfill leachate RO | Landfill leachate after equalization and solids removal | 3,000–20,000+ | 50–75% | 50–500 | 5–300 m³/day | Equalization, ammonia control, biological treatment, ultrafiltration, cartridge filtration | Permit-compliant discharge or controlled concentrate management | Ammonia, PFAS where regulated, metals, organics, chloride, and hazardous-waste rules | The concentrate-management plan is as important as the permeate quality. |
| 06 | Food and beverage wastewater RO | High-organic wastewater from food and beverage processing | 800–4,000 | 65–85% | 20–200 | 10–1,000 m³/day | DAF or clarification, biological treatment, ultrafiltration, cartridge filtration, sanitary cleaning | Cleaning, cooling, utilities, and other non-product-contact operations | Hygiene rules, water-contact classification, COD/BOD, nutrients, and local reuse regulations | Sanitary design and validated cleaning procedures are essential for reliable operation. |
| 07 | Mining and high-TDS wastewater RO | Mine water, process water, and tailings-related wastewater | 3,000–30,000 | 45–75% | 50–500 | 20–2,000 m³/day | Clarification, media filtration, iron and manganese removal, cartridge filtration, antiscalant | Dust suppression, process reuse, controlled discharge, and water recovery | Metals, sulfate, acidity, selenium, boron, salinity, and watershed-specific permits | High-pressure equipment and robust solids handling may be required for difficult feeds. |
| 08 | Seawater-influenced wastewater RO | Coastal municipal or industrial wastewater with saltwater intrusion | 5,000–40,000 | 35–60% | 100–800 | 50–5,000 m³/day | High-quality clarification, ultrafiltration, cartridge filtration, dechlorination, scale control | Industrial reuse, irrigation where salinity permits, and non-potable municipal reuse | Chloride, sodium adsorption ratio, boron, marine discharge, and local reclaimed-water limits | Use seawater-grade high-pressure design only when the feed salinity requires it. |
| 09 | Zero-liquid-discharge RO front end | Industrial wastewater where liquid discharge is restricted | 2,000–50,000 | 60–85% before concentration | 20–300 | 10–1,000 m³/day | Custom chemical treatment, clarification, ultrafiltration, cartridge filtration, antiscalant | Maximum water recovery followed by brine concentrator or crystallizer | Local discharge prohibition, hazardous-waste classification, salt disposal, and energy requirements | RO alone is not zero liquid discharge; downstream concentration and solids handling are necessary. |
| 10 | Potable-reuse advanced treatment train | Highly treated municipal wastewater for indirect or direct potable reuse | 500–2,000 | 75–85% | 5–100 | 100–20,000 m³/day | Microfiltration or ultrafiltration, RO, UV, advanced oxidation, activated carbon where required | Potable supply after regulatory approval and a validated multi-barrier treatment scheme | National drinking-water rules, pathogen controls, trace-organic monitoring, and risk-management plans | The complete treatment train—not RO alone—must satisfy potable-reuse regulations. |