Ceramic Tableware Recycling by Green Life 21 Project - Red Objects

The physicality, safety and environmental burden of recycled tableware with a 20% combination
ratio are described in the following section (Hasegawa et al. 2000).
Table 1 The properties of recycled and conventional tableware
Recycled tableware Conventional tableware
Water absorption % 0.14 - 0.21 None
Density g/cm 3 2.30 - 2.33 ca.2.30 - 2.40
Bending strength MPa 84.5 - 95.0 ca.60.0 - 100.0
2.1 Physicality and Safety
The physicality of recycled tableware is evaluated by measurements of water absorption ratio,
specific gravity and bending strength (Table 1). In the results, water absorption ratio was a little
higher than existing porcelain tableware, but specific gravity and bending strength were almost
equivalent. It can be used without causing any problem in people’s lives. Safety was evaluated by
means of a quenching experiment with a temperature difference by 150 degrees Celsius and a lead
and cadmium elusion test using green body without glaze, into which 50% of crushed tableware
with overglaze decoration was combined. where crushed tableware that had been painted and
decorated was combined at 50%. In the results of both the quenching experiment and elusion test,
there were no anomalies and there was no problem with safety when used as tableware.
Fig.1 The raw material process for recycling tableware
2.2 Quantitative Research on the Environmental Burden
The environmental burden was evaluated by converting energy consumption into CO2 emission
volume. The LCA method was used for the clay preparation and tableware manufacturing
processes of recycled tableware and existing porcelain tableware each. The results are shown in
Table 2. CO2 emission volumes per 1 ton of each product in both processes are almost the same.
Consequently, we found that it was possible to recycle tableware without increasing the
environmental burden.
RED Objects⏐⏐Collaboration in Experimental Design Research
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