Seawater Desalination : Polishing Steps for Demi water production

Polishing Steps for Demi / Ultra pure Water

Ion exchange
Mixed Bed
Electrodyalisis (EDI)

Quality	RO-water	Demi-water	Pure Water	Ultra pure water
Conductivity	10-100 uS/cm	1-10 uS/cm	1-0.1 uS/cm	0.1-0.0555 uS/cm
Resistivity	0.1-0.01 MOhm	0.1-1 MOhm	1-10 MOhm	10-18 MOhm
Polishing step after 1st pass SWRO desalination process	2nd pass BWRO or SWRO (high temperature and salinity)	2nd-pass RO + strong Ion exchange resins	2nd-pass RO + strong Ion exchange resins + Mixed Bed resin	2nd-pass RO + strong Ion exchange resins + EDI or Mixed Bed Nuclear grade resin

Desalination Polishing steps

Reverse Osmosis Desalination Process

Desalination and Energy Costs

Brine Disposal

Storage and Distribution

Instrumentation and Control (SCADA)