Proven processes, next-generation performance

Membrane-based brine concentration that uses a saline sweep stream to take reverse osmosis far beyond its conventional osmotic-pressure limit.

Conventional reverse osmosis becomes impractical once the brine’s osmotic pressure approaches the membrane’s pressure rating — around 70,000–80,000 mg/L TDS for seawater-grade systems. Osmotically Assisted Reverse Osmosis overcomes this limit by circulating a saline sweep solution on the permeate side of the membrane. Because the membrane only has to overcome the difference in osmotic pressure between feed and sweep, brines can be concentrated far beyond the conventional limit at standard RO operating pressures. Several OARO stages work in series, and the diluted sweep is returned through conventional RO to recover fresh water — at a fraction of the energy of thermal evaporation.

Thermal desalination that evaporates water into a carrier air stream and condenses it as distillate — recovering clean water from extremely saline and difficult brines.

In a humidification–dehumidification system, air acts as the carrier for water vapor. In the humidifier the air contacts hot brine and picks up pure water vapor, leaving salts and contaminants behind; in the dehumidifier the vapor condenses into high-purity distillate, and the released heat is recovered to preheat the brine. Because evaporation takes place at atmospheric pressure and below boiling temperature, HDH tolerates very high salinity and the scaling and fouling compounds that would quickly disable membranes or conventional evaporators — and it can run on low-grade heat such as waste heat or solar thermal energy.

High-recovery reverse osmosis in which the concentrate circulates in a closed loop and the pressure follows the rising osmotic pressure, cycle by cycle.

In Closed Circuit Reverse Osmosis, pressurized feed enters a closed loop and the concentrate is recirculated through a single stage of membranes, while fresh feed continuously replaces the permeate produced. As the loop concentrates, the applied pressure rises gradually to match the osmotic pressure — instead of running constantly at the maximum pressure required by the last element of a conventional multi-stage array. Once the target recovery is reached, the concentrate is flushed out and replaced with fresh feed without interrupting production. The result is higher recovery, lower specific energy, and cyclic changes in salinity and flow that disrupt the formation of scale and biofilm.

Targeted removal of the specific contaminants that matter — without treating the entire water matrix.

Many water challenges are caused by a few specific constituents — silica, boron, hardness, heavy metals, selenium, ammonia, nitrate or trace organics — rather than total salinity. Selective Contaminant Removal combines engineered selective adsorbents, specialty ion-exchange and chelating resins, and targeted precipitation chemistry to remove only those contaminants. Treating just what matters lowers chemical and energy demand, protects downstream membranes and evaporators, and can turn recovered constituents into valuable products.

A family of oxidation processes that generate highly reactive hydroxyl radicals to destroy persistent organic pollutants — selected to suit the water and the target compounds.

Advanced oxidation processes generate hydroxyl radicals in situ. The radicals react rapidly and non-selectively with organic molecules, breaking down refractory COD, color, odor, phenols, pharmaceuticals, pesticides and other micropollutants into smaller biodegradable compounds, or mineralizing them completely to carbon dioxide and water. The right process depends on the clarity and chemistry of the water, the target compounds and operating costs. AOP can polish effluent for discharge compliance, pre-treat difficult streams for biological treatment, or protect water reuse systems.

Processes