Incineration is a common method for municipal solid waste treatment since it reduces the amount of waste, enables destruction of pathogens and organic contaminants, as well as possible recovery of energy in form of heat and/or electricity. Figure 1 visualize how fly ash is produced through incineration.
Even though incineration substantially reduces the waste's volume and mass, bottom- and fly ash are produced in large quantities. The fly ash is captured in the incineration plant's air pollution control and is often considered to be a hazardous waste when being disposed in a land fill. This is due to a high content of water-soluble chlorides and heavy metals in the fly ash. Because of its hazardous properties, it is expensive and problematic to manage.
Fly ash from Sweden is today mainly stored in special constructed land fills or on a discharged lime stone mine in Norway. The land fill and storing alternatives are not sustainable in a long-term perspective, but are temporary accepted because there is a lack of attractive alternatives.
Figure 1. How fly ash is produced
The high chloride content of the ash makes it impossible (with current legislation) to land fill it without proper pre-management that avoids leaching of chlorides and stabilizes heavy metals. This pre-management is expensive and today only a few players can handle the fly ash. About 50% of Sweden's produced fly ash is exported to Norway.
EasyMining’s patented Ash2Salt process is unique and can extract commercial salts from high chlorine containing fly ashes. After washing, the ash residue can be land filled without an exemption for high chloride contents. The Ash2Salt process can extract commercial grade:
- Potassium chloride (KCl)
- Sodium chloride (NaCl)
- Calcium chloride (CaCl2)
- Aqueous ammonia solution or ammonium sulfate
- Substantially reduces the hazardousness of fly ash
- Lowers the fly ash's mass by (on average) 20%.
- Creates an income source from commercial valuable salts and ammonia.
- A new energy effective and patented process for separating salts
- In addition to the three salts types, the process also produce an ammonia product that can be used in incineration plants for flue gas treatment
- Separates heavy metals from the fly ash
- Can handle different levels of salts in the fly ash
- Decontaminates and reduces waste
- Converts a linear waste flow into a circular resource flow
- Reduces the need for virgin raw materials
- Recovers potassium, a valuable non-renewable plant nutrient
A new Ash2Salt plant is planned in Högbytorp in Sweden
EasyMining's parent company, Ragn-Sells have come far in the planning of a full scale Ash2Salt plant at their site in Högbytorp, Sweden.