Acrete™ – circular economy
– recycling coal ash into a valuable material
- Reprocessing of coal ash uses proven technology (low risk)
- Acrete is a 3-component building material (coal ash + activator + water)
- Aggregates or retardants can be added for increased workability
- Rapid curing time of 1 day in oven or 3 weeks in open air
- Up to 120MPa compressive strength and up to 9MPa flexure strength.
- Water absorption <6%, making it less prone to hot/cold breakage
- Product is easy to use
- Coal power plant operators (CPPO) need a solution to clean up highly polluting coal ash tailings (est. 20bt stockpiled , est. 1bt produced annually; >1,000 coal ash landfills in the USA alone
- Duke Energy, a large CPPO, has accounted for >US$6bn to treat coal ash to mitigate the risk of contamination (health, water, air, ecosystems etc)
- Concrete producers need an alternative to sand (depleting/scarce resource)
Treated coal ash can be used as either an additive or substitute to sand in cement production (est. US$10bn annual market size).
Acrete is positioned to be a low cost, environmentally friendly building material and an alternative to cement.
Acrete can be used to solidify contaminated mine tailings powders in a high strength material (original research).
|Raw materials||fly ash|
|Dosage||< 10% (in wt%) activator|
(high temperature curing)
|Class C: 70-120 MPa (1 day)
Class F: 60-70 MPa (1 day)
|Class C: 70 MPa (3 weeks)
Class F: 60 MPa (4 weeks)
|Water adsorption ration/td>||<6%|
|Durability in water||high|
|Simplicity||high (curing without a mold)|
|Resource||Fly ash, gravel,activator, water||Cement, fly ash, gravel, sand, water|
|Fly ash dosage
|60-70 MPa (3 weeks)||20-30 MPa (4 weeks)|
|Durability in water||High||Normal|