To produce iron castings in greensand most used components are:

• Silica Sand
• Bentonite
• Coal-dust

The products are applied in a cycle system, a very efficient way to produce. The raw materials are re-used for around 90% and the bentonite binder is inorganic not contributing to emissions.

To produce one metric ton of iron casting you need approx 150 kg silica sand, 80kg go bentoniet and 20kg of coal dust, total around 250 kg this is wast or can be re-used or reclaimed. 

Still if you consider that for 1 MT of casting a greensand mould is produced of 5 MT, only 5% is waste or should be considered for an approach.

If you produce 50.000 MT of castings 12.500 MT of waste sand is created or 62.5 T per day. 

Bentonite and coal dust are consumables. Bentonite looses binding property after been heated above ca. 500 degrees celsius emitting water from dehydroxilation (loosing OH groups). Coal heated above 500 degrees celsius will be transferred to coke a process comparable to cokes production.

This process will form coke (coal residue) gas emissions party further cracked. Emissions are CO, CO2,CH4, BTEX and maybe other components.

We CORIC can help you selecting the best raw materials for your foundry reducing costs and environmental impact this combined with process analyses.