Research, design and development of EDI theory in the 1960s;
The first product EDI was introduced in 1987.
Under the action of direct current, the electrolyte of water is selectively transferred through ion-exchange membrane.
The exchange of ions in water electrolyte was carried out by the exchange resin.
The H+ and OH are generated by the polarization of water in the ion-exchange interface.
Resin is divided into three layers: the first layer: saturated resin layer: adsorption and migration of most electrolytes;
Layer 2: mixed resin layer: weak electrolyte;
Layer 3: protective resin layer: the ultimate purified water.
3. Effect: remove ions in water and produce high pure water.
4. Water inlet indexes:
Ultra pure water type (UPW) pure water type.
Conductivity: less than 8 <20.
CO2 (in CaCO3, PPm) <3 <6.
PH > 7 > 6.2
TOC (PPm) <0.3 <0.5.
SiO2 (PPm) <0.3 <0.5.
Total hardness (CaCO3) <1 <2.
The water temperature is 13 ~ 30, 13 ~ 30.
Fe and Mn (PPm) <0.01 <0.05.
Cl2 (PPm) < 0.05 < 0.05
Oil and grease
5. Operation parameters:
Flow rate: 1.5 ~ 2.3m3 / h/branch.
Flow rate: 0.5 ~ 0.6m3 / h/branch.
Water discharge: 50 ~ 70L/h/branch.
Water discharge: >65L/h/branch.
The pressure of the inlet and outlet should be 0.5 ~ 0.7bar lower than the corresponding fresh water pressure.
Inlet pressure: <4bar.
6. Causes of cleaning:
The scale of the thick water chamber is caused by hardness.
It is polluted by organic matter or inorganic substance.
The contamination of membrane components and system pipes by microorganism.