CE Certification Osmosis-Assisted Reverse Osmosis System for High Salinity Wastewater Concentration - China Suppliers & Factory Solutions Factory, Manufacturers
Product Description
Core Features
In the field of high salinity wastewater treatment, conventional reverse osmosis has long faced a hard technical barrier: when feed TDS exceeds about 75 g/L, the osmotic pressure difference across the membrane forces operating pressure to approach – or even exceed – the safe limits of membrane elements. The traditional solution is to switch to thermal processes such as multi effect evaporation or mechanical vapor recompression (MVR), but thermal concentration consumes over 20 kWh/m³, accounting for up to 80% of the operating cost of a zero liquid discharge (ZLD) system.
OARO fundamentally changes this situation. It cleverly integrates reverse osmosis and forward osmosis principles by introducing a saline draw solution on the permeate side to actively reduce the transmembrane osmotic pressure difference. This keeps the net driving pressure across the membrane within a safe and economical range. This mechanism allows the system to concentrate 35 g/L brine to 125 g/L with an energy consumption as low as 4 kWh/m³, or push brine concentration to the saturation level of 250,000–260,000 ppm under conventional 70 bar pressure. Compared to traditional ZLD routes, OARO can reduce the thermal evaporation/crystallization load by more than 60% and lower total system costs by up to 60%.
Core Process Flow
High salinity wastewater (the feed solution) is pressurised and enters the high pressure side of the OARO membrane element, while a low concentration salt solution (the draw solution, typically prepared by diluting a portion of the system’s own concentrate) flows on the permeate side. Under the applied driving pressure, water molecules migrate from the high pressure side to the low pressure side, the feed concentration continuously increases, and the draw solution is gradually diluted. The diluted draw solution can be either recycled back as fresh draw solution or further desalinated by a downstream RO unit to recover fresh water. Through multi stage counter current series connection, the system can approach salt saturation in a cascading manner.
Application Fields
Zero Liquid Discharge (ZLD)
Specific scenarios: ZLD front‑end membrane concentration for coal chemicals, power plant desulfurization. Dramatically reduces evaporation load and lowers total system cost by up to 60%.
Oil & Gas Produced Water
Effectively treats produced water with high TDS and organics. Membrane flux loss can be reduced from 20% to
Lithium Extraction & Resource Recovery
Concentrates low‑grade brines to saturation, creating ideal conditions for lithium/potassium selective precipitation from salt lakes.
Seawater Desalination Concentrate
Concentrates brine to >250,000 ppm, reducing discharge volume and recovering valuable salts like NaCl for the chlor‑alkali industry.
Industrial Wastewater Salt Recovery
Recovers high-purity salts from textile, pharmaceutical, and electroplating wastewater to offset ZLD operating costs.
RO Concentrate Re‑concentration
Secondary concentration of RO concentrate from 70–80 g/L to >150 g/L, increasing ZLD capacity without expanding evaporators.
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Frequently Asked Questions
OARO (Osmotically Assisted Reverse Osmosis) integrates reverse osmosis and forward osmosis principles by using a draw solution to reduce transmembrane osmotic pressure, allowing for much higher concentration levels than traditional RO.
OARO can reduce energy consumption to as low as 4 kWh/m³ for high-salinity brine, compared to over 20 kWh/m³ required by traditional thermal evaporation processes.
Under conventional 70 bar pressure, OARO systems can push brine concentration to near-saturation levels of 250,000–260,000 ppm.
Yes, OARO is ideal for concentrating low-grade brines from salt lakes to saturation, which is a critical step for subsequent lithium and potassium recovery.
It reduces the thermal evaporation/crystallization load by more than 60%, significantly lowering the total capital and operating costs of Zero Liquid Discharge systems.
Absolutely. OARO handles high TDS, organics, and complex salts effectively, maintaining high membrane flux with minimal loss when paired with proper pre-treatment.
