Home IDE Tech > Water Solutions > Seawater Desalination > Desalination Post Treatment

FROM SEAWATER TO POTABLE USE

IDE develops state-of-art technologies for SWRO post treatment processes

Post-treatment systems are designed to adjust the final product’s chemistry to achieve quality requirements. Typically, these requirements are defined by local regulatory authorities of the state or by the requirements of clients for either drinking water or industrial use.
It is important that the final water meets the desired chemical composition, turbidity, and biological safety requirements. TDS, Total Hardness, Alkalinity, LSI, CCPP, pH, Bacteria and Virus logs are adjusted in the product water.

The following methods are widely used in IDE SWRO plants:

Limestone dissolution in Calcite (CaCO3) reactors, where RO permeate is passed through the reactors and becomes enriched with minerals. Carbon dioxide (CO2) and/or sulfuric acid (H2SO4) are used for limestone dissolution.

Lime water (Ca(OH)2) and/or caustic soda (NaOH) are used for final adjustments of LSI and pH parameters.

Chemicals addition – lime water and CO2 dosing.

Water disinfection by dosing of sodium hypochlorite (NaClO) also provides residual free chlorine demand.

IDE plants feature the latest self-generation systems for chemicals. Our main goal is to eliminate dependence on external sources and avoid shortages. The on-site generation offers lower operating costs than commercial chemicals and provides high-quality chemicals.

The following self-generation systems are already implemented in some of IDE’s mega SWRO plants

Carbon di-oxide (CO2) generation: The production of CO2 can be typically obtained from a power plant source. The main processes for producing CO2 are extraction from flue gases, purification, and liquefaction. The recovery of CO2 from flue gas sources also contributes to reducing CO2 emissions to the atmosphere.

Sodium Hypochlorite (NaOCl): This is used for disinfection produced on-site by electrochlorination. By producing hypochlorite on-site and on-demand, the system eliminates concerns regarding transportation and storage. Due to its low concentration, the hypochlorite solution generated by the electrochlorination minimizes corrosion and chemical degradation during prolonged storage.

Lime water (Ca(OH)2) preparation: A new alternative lime water dissolution and clarification system was developed in order to improve the conventional system. The main purpose of the system is to prepare the concentrated and highly pure lime water solution that highly improves the final water quality. The new approach is based on state-of-art ceramic membranes that allow it to operate at high fluxes