Return to Menu

HISTORY

1959. Naoshima, Japan

Research began in 1959 to develop a new smelting mechanism. Experiments were conducted at the Naoshima Smelter using the then-existing slag fuming furnace on "injection smelting", which involved injecting the charge materials and pressurized air into a molten bath.

These experiments showed that this new method would enable rapid smelting of concentrates with low-copper slag. A small-scale pilot plant was then built at Naoshima for further experiments. The test operation confirmed the technical superiority of the new smelting mechanism.

However, for the commercialization of a continuous process incorporating this new smelting method, various technical problems such as the improvement of the service life of the tuyeres and the transfer of intermediate products, still remained to be solved.

1968. Onahama, Japan

A pilot plant, with a design capacity of 6,000 mtpy copper, was constructed at the Onahama Smelter of Onahama Smelting & Refining Co., Ltd., a subsidiary of Mitsubishi Metal Corporation (now Mitsubishi Materials Corporation).

In this pilot plant, top-blow lances were successfully used instead of tuyeres. The pilot operation continued for two years and established the basic design and operation parameters of the Mitsubishi Process.

1970. Onahama, Japan

As a preparatory step for future commercialization, a semi-commercial plant, with a design capacity of 18,000 mtpy copper was built at Onahama.

Through the operation of this plant, the data necessary for the construction of a commercial unit was accumulated, and a process control system was developed.

1974. Naoshima, Japan

First commercial installation, with an original design capacity of 48,000 mtpy copper, utilizing the Mitsubishi Process was established.
By 1980, as a result of productivity improvements, including increased solids feed, and the use of higher oxygen/air ratios for the S and C furnace lance blowing, the plant capacity was lifted to 90,000 mtpy without any change in furnace dimensions.

1981. Timmins, Canada

First Mitsubishi Process Licensee, Texasgulf Canada, a subsidiary of Texasgulf Inc. (later acquired by Falconbridge), established a new continuous copper smelter at Timmins, Ontario with an original design capacity of 60,000 mtpy copper.
In 1983 Mitsubishi Materials provided a basic engineering package to increase the Mitsubishi Process plant capacity at Timmins to over 90,000 mtpy copper, utilizing higher oxygen enrichment.
Phased plant modifications and additions started at Timmins in 1984 and were completed by mid 1986. At each stage, the anticipated increases in blister production were achieved with no changes having to be made to furnace dimensions.
The optimization of oxygen enrichment and other general improvements have further improved the Mitsubishi Process plant capacity at Timmins to over 125,000 mtpy.
The plant was shutdown in 2010 due to the drain of copper mine.

1991. Naoshima, Japan

New Mitsubishi Process plant was established, with a design capacity of 204,000 mtpy copper.
This new Mitsubishi Process plant has, as planned, successfully rationalized Naoshima's copper operations by completely replacing the older conventional (Reverb/P-S) smelter, the original Mitsubishi Process plant, and their respective anode casting plants.
The capacity was increased to 270,000 mtpy of copper in 2003.

1997. Onsan, South Korea

Second Mitsubishi Process licensee, LG Metals (Currently LG-Nikko) establishesd a new Mitsubishi Process line in addition to their conventional flash smelter + PS convertor line, to increase total output. The Mitsubishi Process was selected over other processes, first for enviornmental considerations, and second for production economy.
In addition to supplying proprietory equipment, Mitsubishi also supplied LG with basic engineering services, technical advisory services during the detailed engineering and construction phase, training and start-up assistance.
The designed production was acheived in 1998, and the capacity reached to 270,000 mtpy copper in 2006.
To this day, Mitsubishi and LG-Nilkko share a close working relationship.

1998. Gresik, Indonesia

Third overseas plant was built in Gresik, Indonesia. The plant is run by a consortium consisting of Mitsubishi Materials Corp., PT Freeport Indonesia, Mitsubishi Corp., and Nippon Mining, and has a design capacity of 200,000 mtpy.
The Gresik smelter, being built on a greenfeild site, incorporates many improvements in design over Naoshima, including better overall layout. This has led the smelter to be described by Dr. Herbert H. Kellog, former professor of Columbia Univerity, as "the finest copper plant that I have seen." (from the Journal of Metals, Vol.52, No.11, November 2000).
The smelter produced 214,000 mtpy of new anode in 2001, and the capacity reached to 300,000 mtpy in 2009.

1999. Port Kembla, Australia

Mitsubishi Converting furnace (C-furnace) technology was licensed to Port Kembla Copper Pty., Ltd., and coupled with pre-existing Noranda reactor. The Mitsubishi C-furnace replaced existing Pierce-Smith convertors. Although the first of its kind in this endevour, it is hoped that more smelters around the world will embrace Mitsubishi 's C-furnace technology as a more environmentally sound alternative to current Pierce-Smith Convertors.
The capacity was small, only 140,000 mtpy, and the plant was shut down in 2003 due to the economical reason.

2005. Dahej, India

Hindalco Birla Copper established a new Mitsubishi Process line with a capacity of 250,000 mtpy copper, in addition to their conventional flash smelter + PS converters line and Ausmelt smelter and converter line.
Mitsubishi supplied HBC with basic engineering services, propriety equipment and training and start-up assistance. Technical advisory services have been supplied up to now.

2007. Onahama, Japan

Stand - alone Mitsubishi S furnace was additionally installed to reverberatory furnaces and PS converters line for increasing the treatment capacity of copper concentrates and recycle materials. Copper concentrates are mainly treated at S furanace with the capacity of 200,000 mtpy copper.

* Comparison of Mitsubishi Process Smelters *

Return to Menu