There is a small amount of APCR (air pollution control residue), which is sometimes called fly ash. APCR is typically a mixture of ash, carbon and lime (or bicarbonate). It is classed as a hazardous waste because of its high alkaline content from the spent lime, which is used as part of the filtering and cleaning process to remove acid gases. In the past it was disposed of at a hazardous waste landfill but nowadays it may undergo further processing such as washing or stabilisation before being sent to a non-hazardous landfill. It is a small volume of material from the process.
However, landfilling of APCR will be discontinued as new regulations come into effect. Many chemical treatment companies have anticipated this situation, with new facilities being opened which are now capable of achieving ‘end of waste’ status for the washed and cleaned aggregates contained in the APCR.
There is an amount of ferrous and non-ferrous metal, which can be extracted from the ash or by the mechanical treatment facility (MTF) that will be on site, and sent for reprocessing by a scrap merchant.