26 Recyclability of Tungsten, Tantalum and Neodymium …
367
disassembly of even small mobile devices are however on the rise through semiautomated and fully automated disassembly lines, as exemplified by the Daisy robots
from Apple (Apple 2019).
Apart from the safe removal of lithium batteries, disassembly robots may also
target repair, refurbishment or parts scavenging and therefore use circular economy
principles as economic drivers, and improved material separation and recovery as
second order benefits.
The goal of this analysis is to provide quantified details from disassembly studies
of smartphones regarding the three target metals. Intentionally omitting the steps,
costs and problems of the automated separation of parts (covered in other research),
the link to currently existing recycling processes is discussed. Future recycling
potentials and avenues of further action are addressed.
To complement the fact finding from disassembly case studies on the lab scale
and the results from literature research, interviews with recycling companies were
carried out. Example findings from these interviews are shown in the results chapter.
26.2 Characteristics and Recycling of Tungsten, Tantalum
and Neodymium
26.2.1 Tungsten
On average the earth’s crust contains around 1.25 g/ton of tungsten (Willersen
2016). Tungsten is a metal of the refractory group with high hardness, high density
(19.25 g/cm
3 ) and a melting point at 3422 °C. Tungsten is one of the T3G conflict
minerals because of the high economic importance, its unique properties and the high
supply risk when depending on imports. The major producers are: China, Russia,
Bolivia and North America but it is also mined in Austria. In 2014, about 82% of the
global tungsten production came from China (Reichl et al. 2016). When combined
with carbon to make tungsten carbide, it is almost as hard as diamond. These and
other properties make it useful in a wide variety of important commercial, industrial,
and military applications (see Fig. 26.2).
The leading use for tungsten is as tungsten carbide in cemented carbides, which are
wear-resistant materials used by the construction, metalworking, mining, oil and gas
drilling industries. Pure or doped tungsten metal is used for contacts, electrodes, and
wires in electrical, electronic, heating, lighting, and welding applications. Tungsten
is also used to make alloys and composites to substitute for lead in ammunition,
radiation shielding, and counterweights, super alloys for turbine engine parts as
well as coatings. Tungsten chemicals are used to make catalysts, corrosion-resistant
coatings, dyes and pigments, fire-resistant compounds, lubricants, phosphors and
semiconductors. Tungsten has three primary uses in electronic products: vibration
motors, integrated circuits and liquid crystal displays (LCD) (USGS 2014).
367
disassembly of even small mobile devices are however on the rise through semiautomated and fully automated disassembly lines, as exemplified by the Daisy robots
from Apple (Apple 2019).
Apart from the safe removal of lithium batteries, disassembly robots may also
target repair, refurbishment or parts scavenging and therefore use circular economy
principles as economic drivers, and improved material separation and recovery as
second order benefits.
The goal of this analysis is to provide quantified details from disassembly studies
of smartphones regarding the three target metals. Intentionally omitting the steps,
costs and problems of the automated separation of parts (covered in other research),
the link to currently existing recycling processes is discussed. Future recycling
potentials and avenues of further action are addressed.
To complement the fact finding from disassembly case studies on the lab scale
and the results from literature research, interviews with recycling companies were
carried out. Example findings from these interviews are shown in the results chapter.
26.2 Characteristics and Recycling of Tungsten, Tantalum
and Neodymium
26.2.1 Tungsten
On average the earth’s crust contains around 1.25 g/ton of tungsten (Willersen
2016). Tungsten is a metal of the refractory group with high hardness, high density
(19.25 g/cm
3 ) and a melting point at 3422 °C. Tungsten is one of the T3G conflict
minerals because of the high economic importance, its unique properties and the high
supply risk when depending on imports. The major producers are: China, Russia,
Bolivia and North America but it is also mined in Austria. In 2014, about 82% of the
global tungsten production came from China (Reichl et al. 2016). When combined
with carbon to make tungsten carbide, it is almost as hard as diamond. These and
other properties make it useful in a wide variety of important commercial, industrial,
and military applications (see Fig. 26.2).
The leading use for tungsten is as tungsten carbide in cemented carbides, which are
wear-resistant materials used by the construction, metalworking, mining, oil and gas
drilling industries. Pure or doped tungsten metal is used for contacts, electrodes, and
wires in electrical, electronic, heating, lighting, and welding applications. Tungsten
is also used to make alloys and composites to substitute for lead in ammunition,
radiation shielding, and counterweights, super alloys for turbine engine parts as
well as coatings. Tungsten chemicals are used to make catalysts, corrosion-resistant
coatings, dyes and pigments, fire-resistant compounds, lubricants, phosphors and
semiconductors. Tungsten has three primary uses in electronic products: vibration
motors, integrated circuits and liquid crystal displays (LCD) (USGS 2014).