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E. Shibata
technologies in terms of recycling of solid wastes. However, as secondary raw materials containing waste plastics such as printed circuit boards and shredder residues
contain bromine flame retardants and polyvinylchloride, it is necessary to deal with
associated corrosion problems for exhaust gas treatment facilities.
Effective Use of Lead Smelters
Unlike copper smelting, lead smelting is a process that can operate with only secondary raw materials using existing facilities such as lead blast furnaces (originally
operated for concentrates). At present, it is estimated that about half of the lead
bullion is produced from secondary raw materials in Japan [9]. In a lead smelting
furnace, it is possible to control multiple phases such as gaseous components, slag,
matte, speiss, and molten lead. From this point, it is obvious that the lead smelting
process can separate and recover various metals efficiently [10–14].
In lead smelting process, precious metals, Sb, and Bi can be recovered from
anode slime generated by electrorefining. Copper matte generated in the furnaces
and the dross recovered by decopperization of lead bullion can be used as copper
raw materials. Sn is also recovered by Harris treatment of lead bullion [10–14].
Lead smelters are also responsible for treating smelting residues from other nonferrous smelters. In addition, lead smelters must play a vital role in treating solder
and various mounting components generated by physical separation treatments of
printed circuit boards. By charging these components into the lead smelter, Sn, Sb,
Bi, and precious metals can be recovered without serious problems. Thus, the lead
smelter plays a central role in the construction of a metal resource circulation system
based on the non-ferrous smelting industry. The lead smelters are indispensable for
waste treatments in Japan. For example, a CRT glass that contains lead was efficiently
treated as a substitute for flux in lead smelting furnaces [15]. As an example from
overseas, Umicore process in Hoboken is a typical process that combines a lead
smelting furnace (blast furnace) and a copper smelting furnace (TSL furnace) [16].
The Importance of ISP
There are two processes involved zinc smelting and refining: hydrometallurgical
zinc smelting [17–20], which is the main zinc production process, and ISP (Imperial
Smelting Process) [21] in Japan. An important secondary raw material for zinc is
EAF (electric arc furnace) dust generated from an electric furnace for recycling iron
scrap. As EAF dust contains zinc from the galvanization of steel, crude zinc oxide is
produced using EAF dust as a raw material. A typical process for producing crude
zinc oxide is the Waelz kiln method [22, 23]. In addition, the MF (Mitsui Furnace)
process, which uses a characteristic blast furnace [24], is also operated in Japan.
The MF process produces crude zinc oxide from EAF dust and molten fly ash as a
E. Shibata
technologies in terms of recycling of solid wastes. However, as secondary raw materials containing waste plastics such as printed circuit boards and shredder residues
contain bromine flame retardants and polyvinylchloride, it is necessary to deal with
associated corrosion problems for exhaust gas treatment facilities.
Effective Use of Lead Smelters
Unlike copper smelting, lead smelting is a process that can operate with only secondary raw materials using existing facilities such as lead blast furnaces (originally
operated for concentrates). At present, it is estimated that about half of the lead
bullion is produced from secondary raw materials in Japan [9]. In a lead smelting
furnace, it is possible to control multiple phases such as gaseous components, slag,
matte, speiss, and molten lead. From this point, it is obvious that the lead smelting
process can separate and recover various metals efficiently [10–14].
In lead smelting process, precious metals, Sb, and Bi can be recovered from
anode slime generated by electrorefining. Copper matte generated in the furnaces
and the dross recovered by decopperization of lead bullion can be used as copper
raw materials. Sn is also recovered by Harris treatment of lead bullion [10–14].
Lead smelters are also responsible for treating smelting residues from other nonferrous smelters. In addition, lead smelters must play a vital role in treating solder
and various mounting components generated by physical separation treatments of
printed circuit boards. By charging these components into the lead smelter, Sn, Sb,
Bi, and precious metals can be recovered without serious problems. Thus, the lead
smelter plays a central role in the construction of a metal resource circulation system
based on the non-ferrous smelting industry. The lead smelters are indispensable for
waste treatments in Japan. For example, a CRT glass that contains lead was efficiently
treated as a substitute for flux in lead smelting furnaces [15]. As an example from
overseas, Umicore process in Hoboken is a typical process that combines a lead
smelting furnace (blast furnace) and a copper smelting furnace (TSL furnace) [16].
The Importance of ISP
There are two processes involved zinc smelting and refining: hydrometallurgical
zinc smelting [17–20], which is the main zinc production process, and ISP (Imperial
Smelting Process) [21] in Japan. An important secondary raw material for zinc is
EAF (electric arc furnace) dust generated from an electric furnace for recycling iron
scrap. As EAF dust contains zinc from the galvanization of steel, crude zinc oxide is
produced using EAF dust as a raw material. A typical process for producing crude
zinc oxide is the Waelz kiln method [22, 23]. In addition, the MF (Mitsui Furnace)
process, which uses a characteristic blast furnace [24], is also operated in Japan.
The MF process produces crude zinc oxide from EAF dust and molten fly ash as a