The Recbuild process allows to transform mixtures of wastes in lightweight granulates with excellent physical, mechanical and chemical properties.
The necessary components for the process are:
- coal combustion ashes;
- steel making dust;
- expanding additive already patented.
Through a baking process at high temperature in a rotating oven it's possible to obtain grains with the following characteristics:
|Properties||Aggregate 1||Aggregate 2||Reference norm |
|Grain size||0,5-4mm||4-12mm||UNI 7549/3|
|Apparent particle density ||693kg/m3||956kg/m3||UNI 7549/5|
|Real density of the grains ||1625kg/m3||1126kg/m3||UNI 7549/4|
|Water absorption after 24 hour||3,74%||4,83%||UNI 7549/6|
|Compressive (crushing) resistance ||24,3MPa||8,44MPa||UNI 7549/7|
|Steam stability ||> 99,9%||> 99,9%||UNI 7549/11|
|Freezing/thawing resistance||> 99,9%||> 99,9%||UNI 7549/10|
|Leaching tests with CO2 and acetic acid||Inferior to the limits of table A||Inferior to the limits of table A||Dpr 915/82|
These characteristics make the obtained lightweight aggregate surely superior to the traditional expanded clay actually on the market.
Till now this process has been developed only at lab level using a electric rotative oven but in future it will be possible to produce consistent lots of these aggregates using a plant similar to the one used for the experimentation of the LAW process.