NIPPON RENSUI CO.- Ultrapure Water Production -

Natural water as river water and ground water contains various substances such as suspended solids, micro sized particle, bacteria, ions, silica and organic matters. The quantity of such substances in the natural water is equal to about one-two of 200 liters sized drums for the swimming pool having 50 meter length.
After treating by various units, it can be reduced to the level of less than a spoon of ear pick.
This is a level of ultrapure water.

1) Ultrapure Water System for Micro-electronics Industries

	Ultrapure water system
	To achieve highly purified water production required for rinsing micro-electronics devices, from the raw water as industrial water or well water, many technologies of filtration, ion exchange, membrane, separation, degassing and sterilization are applied.

	Water reclaim system
	The water discharged from the rinsing process is recovered and reused for saving the water resources and protecting the environment. For the sake organic adsorption, ion exchange, oxidization for organic decomposition and membrane separation are applied.

Waste water treatment system

Each substance in the discharged water should be treated to the level of less than the limitation established by environment related laws and regulations.
The residual sludge will be generally treated as industrial waste, however, a part of them will be reused as the raw material for cement or fertilizer.
The technologies of coagulation /precipitation, biological treatment, membrane separation, ion exchange, evaporation, fermentation, dehydration and deorderization are applied.

RO Unit

UV Sterilizer

Degassing Membrane
UF Unit

2) New technology

Chemical less system

This system uses the membrane to remove ionic components in stead of ion exchange resin requiring hydrochloric acid and caustic soda for the regeneration.
The merits of this system are;

	No equipment for neutralization of the waste water is necessary.
	It is possible to operate for long period without the interruption.
	It requires narrow space compared with the conventional system.

It also meets to the requirement of ISO 14000.

	Closed system
	This technology will satisfy the customer who is bothering about the shortage of water source. It consists of mainly ion exchange process and provides high recovery ratio, however, membrane and UV oxidization process will be adopted in this system if required.

	System improvement
	All our systems are always simplified, standardized and economized.

Technology of evaluation method

The analytical technology for ultra micro amount of metals, anions and particles is necessary for the following evaluation.

	The impurities released from system components for the confirmation of their adaptability
	The performance of each treating unit
	The quality of the produced ultrapure water

We look ahead to the future of "Giga bits age" in semi conductor field and will exert our bests for further development of this technology.