Suitability of ash for the production of earth

The report of the Federal Environment Agency examines the possible use of ashes from biomass and coal combustion plants for the production of high-quality earths, e.g. for recultivation or greening. Carbonation — the chemical reaction of calcium oxide with water and carbon dioxide to calcium carbonate — improves the recoverability of ash from biomass combustion. The addition of compost promotes this process and creates high-quality raw material for soiling. In compliance with the quality requirements set out in the Federal Waste Management Plan, only grobas from the incineration of untreated and pure biomass (no waste co-incineration) may be used for soiling. The use of ash from the combustion of coal is currently not recommended due to the varying quality.