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Release: October 14, 2003

NGK Completes the Construction of a Mass-Production Plant
for Ceramic Membranes for Water Purification

1. Location	On the premises of NGK Adrek Co., Ltd. Misano, Mitake, Kani, Gifu Prefecture, Japan
2. Construction and size	Steel-frame one-story (partly two-story) building Approximately 3,000 m2
3. Construction period	December 2002-September 2003
4. Investment amount	Approximately 1 billion yen (building and facilities)
5. Production capacity	5,000 units/year (expandable to 10,000 units/year in the future)

Currently, there are approximately 15,000 water treatment plants in Japan. Most of them were constructed from the 1950s throughout the 1970s, and there are increasing needs for those aging facilities to be renewed and remodeled. In addition, the development of new technologies including the membrane purification system is advancing rapidly in replacement of a conventional sand filtration system.
In 1989, NGK started to develop a water treatment system using ceramic membranes, focusing on the safety and durability of ceramics. From 1991 to 1993, the company participated in the "MAC 21 Project": a project sponsored by Japan's Ministry of Health and Welfare (currently the Ministry of Health, Labor and Welfare) for the research and development of a drinking water treatment system using a membrane technology. From 1997 to 2001, NGK participated in the "ACT 21 Project", a project for the research and development of a high-efficiency potable water treatment technology. Currently, the company is taking part in a project called the "e-Water" from 2002 to 2004, developing a large-capacity water filtration technology employing membranes.
NGK has many years' experience with ceramic membranes for microfiltration in the pharmaceutical and food processing industries. In 1996, the company developed Japan's first ceramic membrane water treatment system applying its original ceramic membrane filters (30 mm in diameter, 1,000 mm in length). The system has been distributed mainly to small-scale water treatment facilities for public water systems.
In 2000, NGK developed a water treatment system using large ceramic membranes (180 mm in diameter, 1,000 mm in length) targeting large savings in cost and space. The company has made marketing efforts to increase the number of orders from mid to large-scale water treatment plants, and accordingly, delivered the nation's largest water treatment system utilizing a ceramic membrane technology to the Bureau of Waterworks of Tokyo Metropolitan Government.
NGK will strengthen its sales activity to expand its share in the membrane filtration system market as a water treatment engineering company with its unique ceramic membranes.

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Outline of NGK Ceramic Membrane Water Treatment Systems

Compared to polymeric membranes such as hollow fiber, ceramic membranes can provide safer water because their high mechanical strength prevents membranes from breaking. In addition, the running cost is low due to the ceramic membrane's durability. NGK's water treatment system employs monolithic (honeycomb-shaped), internal-pressure type ceramic membrane elements of 180 mm in diameter, 1,000 mm in length and 15 m² of a membrane surface area. Microfiltration through highly-porous ceramic membranes with pores 0.1 µm in size enables the elimination of impurities such as turbidity, E. coli bacteria and cryptosporidium (pathogenic protozoa) contained in raw water.

[Characteristics of Ceramic Membrane Elements]

1. Longer operation due to the absence of chemical degradation and deterioration by heat and pressure.
2. No dissolution of impurities from a membrane due to its superior thermal/acid resistance.
3. No breakage of a membrane due to its high mechanical strength.
4. Easier recovery of the membrane performance with chemical cleaning because of the superior chemical corrosion resistance.
5. Recyclability of a used membrane as ceramic raw materials for other products.

[Characteristics of Ceramic Membrane Water Treatment System]

1. Stable treatment performance capable of coping with the fluctuation of the raw water turbidity.
2. Saving the footprint without a need for sedimentation and rapid filtration tanks.
3. Unattended operation with fully automated systems, including a backwash process.
4. A long-life ceramic membrane allows less-frequent replacement of a membrane.
5. Dead-end filtration enables a high recovery rate of water (98% or higher).
6. Low running cost per unit volume of filtrate (approx.¥5/m³).
7. Applicable to the removal of dissoluble iron, manganese, color and odor combined with other treatment processes; thus capable of purifying various types of raw water.

In July 2000, the large ceramic membrane module received certification from the Association of Membrane Separation Technology, and the ceramic membrane water treatment system was certified by the Japan Water Research Center in November 2000.