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EDI maximum information

Apr 25, 2018

1. Development:

Research, design and development of EDI theory in the 1960s;

The first product EDI was introduced in 1987.

2. Principle:


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.