Portable / Pack
External Case Separation
Thermal Treatment i h2o co2
Nickel and Cobalt recovery
Figure 10 : Schematic Presentation of a Ni-MH Battery Recycling
INMETCO is primarly a stainless steel recycler. They process about 50,000 tons of materials containing iron, nickel, and chromium per year, and return an Fe-Ni-Cr alloy back to the stainless steel industry for production of new alloys. As part of their recycling operation INMETCO has accepted both NiCd and NiFe batteries as well as EAF dust, electroplating sludges, and process wastes, all of which may contain some cadmium. The cadmium, and the other low melting elements, lead and zinc, are fumed off either during a rotary hearth furnace treatment or electric arc furnace melting operation. The zinc, lead and cadmium dust which is fumed off during these two operations is collected as a filter cake from a wet scrubber or as a bag-house dust. This Zn-Pb-Cd product is subsequently sent to Horsehead Resources Development Corporation where it is separated into zinc, lead, and cadmium and returned to the marketplace.
INMETCO is capable of handling both portable and industrial NiCd batteries, and is permitted to recycle up to 10,000 tons of NiCd batteries per year. Since INMETCO is primarly a stainless steel recycler, the economics of their NiCd battery recycling process is not as dependent on current cadmium prices as are those of recyclers who are dedicated to NiCd battery recycling alone.
Flow sheets of the INMETCO recycling processes for industrial and consumer NiCd batteries are presented in chapter 4 of this book.
3/ KOREA : NIPPON RECYCLE CENTER
NIPPON RECYCLE CENTER was established in Japan in 1976.
In 1985, NIPPON RECYCLE CENTER made the decision to move their operation to Korea due to an increase in both production and consumption of NiCd batteries in this country. The strategy was to take advantage of this new market while strengthening the companies competitive position by reducing costs. HANIL METAL RECYCLE was thus formed as a joint venture based on the foreign capital inducement act. A new and enlarged plant was completed in 1987 in Korea's largest industrial park Changwon Kongup Kiji.
For the past 15 years, Nippon Recycle Center / Hanil Metal Recycle have been an important link in the recycling chain for NiCd batteries. In so doing they have contributed to enhancing the social utility of NiCd batteries.
This plant discontinued operations in 2000 due to the difficulty of obtaining supplies from Japan.
However, in mid-2001 a new company was formed, KOBAR Ltd., in a small town not far from Changwon City. Run by former technical executives from Hanil Metal Recycle, the plant uses greatly improved technology. Its initial capacity is limited to 1,000 tonnes/year.
In Japan, the largest cadmium consumer and the largest NiCd battery producer in the world, there is fairly extensive pyrometallurgical recycling of NiCd batteries. Both Kansai Catalyst and Toho Zinc integrate their NiCd battery recycling into the zinc cadmium refinery plant, and recover cadmium and iron nickel oxides from a rotary kiln process operated at 1000°C. Industrial batteries are dismantled and sealed cells are first crushed prior to the high temperature treatment. The cadmium oxide is then introduced into the zinc refinery circuit where it is refined to high purity cadmium. The iron-nickel oxides are sold to the steel industry. Toho Zinc also has the capability of treating NiCd battery industry process sludges to recover nickel and cadmium by wet chemical methods. In this circuit, the sludges are leached by sulfuric acid, purified, and then treated with sulfur to produce a cadmium sulfide product which can also be introduced into the zinc refinery circuit for purification into high purity cadmium. The nickel is recovered and sold as a nickel carbonate. The recycling capacity of Toho Zinc is estimated at about 2,000 tons per year, while Kansai Catalyst is believed to be capable of recycling from 500 to 1,000 tons of spent Ni Cd batteries per year.
The other major Japanese recycling plant, JAPAN RECYCLE CENTER, dismantles or crushes industrial and consumer NiCd batteries which have been separated from other cell chemistries. Plastic or steel casings are sent directly off for sale as scrap, while the crushed cells or dismantled electrodes are heated in a vacuum furnace at elevated temperature to volatilize the cadmium. The cadmium so collected may subsequently be refined to a higher purity metal or converted to cadmium oxide for battery industry use. JAPAN RECYCLE CENTER has a NiCd battery recycling capacity of over 2,000 tons of spent batteries and production scraps per year. At present, the Japanese NiCd battery recyclers have far greater recycling capacity than is utilized due to the low cadmium and nickel prices and an insufficient supply of collected NiCd batteries.
In Figure 11, the Nippon Recycle Center process is presented.
Battery Scraps & Wastes
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