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Hitachi

Hitachi Infrastructure Systems (Asia) Pte. Ltd.

We scientifically treat water with advanced technology.

Overview

Preserving the environment and securing our precious water resources are important topics. To solve these issues, advanced treatment is needed for the large amount of water that is discharged every day, and this water needs to be re-used.
We have utilized our long experience and history to develop our waste water recovery and re-use system to respond to these needs. Our system is economical, only takes up a small area, conserves energy, and conserves power.

System & device summary

Photograph: Waste water recovery equipment for electronic device plants
Waste water recovery equipment for electronic device plants

Image: System flow example
System flow example

Removed components and treatment methods

Removed components and treatment methods
  Removed components
Treatment method Turbidity Oil Organic matter Heavy metals Electrolytes Silica Bacteria
Coagulation sedimentation Most of it can be removed Most of it can be removed Some components can be removed Some components can be removed   Most of it can be removed  
Coagulation filtration Most of it can be removed   Some components can be removed Some components can be removed      
Sand filtering Most of it can be removed            
Activated carbon adsorption Some components can be removed Most of it can be removed Most of it can be removed        
Biological activated carbon Some components can be removed Most of it can be removed Most of it can be removed        
Ion-exchange resin     Some components can be removed Most of it can be removed Most of it can be removed Most of it can be removed Some components can be removed
MF membrane Most of it can be removed It can be removed, but it is removed by a large amount of immersion Most of it can be removed       Most of it can be removed
UF membrane Most of it can be removed It can be removed, but it is removed by a large amount of immersion It can be removed, but it is removed by a large amount of immersion       Most of it can be removed
RO membrane It can be removed, but it is removed by a large amount of immersion It can be removed, but it is removed by a large amount of immersion It can be removed, but it is removed by a large amount of immersion Most of it can be removed Most of it can be removed Most of it can be removed Most of it can be removed
Ultraviolet oxidation     Most of it can be removed       Most of it can be removed
Round black stamp
Most of it can be removed
Triangular black stamp
Some components can be removed
Round stamp
It can be removed, but it is removed by a large amount of immersion

Example of target recovered water quality [our application example]

Example of target recovered water quality
  Recovery applications
Item Non-potable water
(Washing cars)
Gray water
(Toilet flushing water)
Industrial water
(Supplemental cooling water)
Pure water
(For boilers)
Water temperature Room temperature Room temperature Room temperature Room temperature
pH 6.5-9.0 5.8-8.6 6.0-8.0 Moderate
Residual chlorine per liter 0.2-0.5 mg No setting for EP No setting for EP Not detected
Turbidity Level 5 Level 3 Level 1 No setting for EP
SS per liter 5mg 3mg 1mg No setting for EP
Evaporation residue per liter 500mg No setting for EP 300mg No setting for EP
CODMn per liter 20mg 30mg 0.5mg No setting for EP
BOD per liter 10mg 15mg 1mg No setting for EP
Electrical conductivity per centimeter No setting for EP No setting for EP 240 μ 0.5 μ
Calcium per liter No setting for EP No setting for EP 60mg No setting for EP
Sodium per liter No setting for EP No setting for EP 20mg No setting for EP
Total hardness per 1CaCO3 200mg No setting for EP 50mg No setting for EP
Cl per liter No setting for EP No setting for EP 11mg No setting for EP
Sulfate ions per liter No setting for EP No setting for EP 20mg No setting for EP
T-SiO2 per liter No setting for EP No setting for EP 22mg 0.02mg
Asterisk
No setting for EP

Applications

  • Semiconductor industry & precision machine industry