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March 23, 1998

Hitachi to Develop Kiln-type Waste Thermolysis System

- 20 ton/day pilot waste treatment plant to be built in Hitachinaka City -

The thermolysis process is superior to conventional waste incineration methods in a number of ways, including its ability to reduce total CO2 by efficient utilization of waste energy, to lower dioxin generation, and to melt and solidify the residual ash. Such capabilities enable the system to overcome many of drawbacks of conventional waste incineration methods and make it a primary candidate for use in next- generation waste processing.

Plans call for the pilot thermolysis plant to be completed in 1998 and tested in 1999. Orders will be actively sought following Ministry of Health and Welfare approval in 2000.

In response to the global need for stronger environmental protection, thirty companies of the Hitachi Group have moved to combine their technologyresources under a wide- ranging environmental program called "Echo 2000." The thermolysis system, viewed as key element in this program, is beingjointly developed by Hitachi and Babcock-Hitachi.

The development strategy is to combine Babcock-Hitachi's boiler and exhaust gas treatment technologies with Hitachi 's coal gasification and slag melting technologies, while applying the know-how accrued by Babcock Hitachi over many years of business in the refuse incinerator business.

The kiln-type thermolyzer will use basic technology that was developed by THIDE ENVIRONNEMENT SA of France and has been tested for more than 4,000 hours at its pilot plant. Hitachi, Ltd. obtained rights to the technology under a licensing agreement concluded with THIDE and later granted a sublicense to Hitachi-Babcock.

In the Thide system, the gas generated by baking refuse in the thermolyzer is used as fuel for heating the thermolyzer and superheating steam for power generation.

The carbonaceous residue, called char, is processed formetal recovery and then fed to the melting furnace.

The Hitachi kiln-type thermolysis system is designed to:

1. Reduce the thermolyzer to about one-half the conventional length and stabilize operation, by incorporating an independent drier.
2. Enable the thermolyzer to generate combustible gas that contains almost no chlorine and is therefore noncorrosive, can be burned to heat the thermolyzer, and can be used to generate high-temperature, high- pressure (500 C degrees, 100 atmospheres) superheated steam for efficient power generation.
3. Permit recovery and recycling of unoxidized metals from the thermolyzer.
4. Utilize as a vertical cyclone melting furnace that achieves a high slagging rate of around 90%, minimizes carry-overs, reduces dioxin generation, and uses a low- temperature activated catalyst to hold the dioxin content of the exhaust gas to under 0.01ng-TEQ/Nm3.

THIDE ENVIRONNEMENT SA in Profile

Location:	Near Paris
Established:	1994 (previously the environment division of SAGED SA)
CEO:	Rene Willemin
Businesses:	Construction of waste treatment plants using the kiln-type thermolysis system. Has completed testing at a pilot plant and is expanding its business mainly in the European market.

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