What is Refuse Derived Fuel?
Refuse derived fuel (RDF) is produced by the mechanical processing of solid waste. For use in a kiln, a typical processing scheme for production of RDF might include shredding, screening, and air classification of the wastes. The fuel properties of RDF vary somewhat among plants and processing schemes but in comparison with typical coal properties, refuse derived fuels are generally lower in calorific value and sulphur content but higher in chlorine content. The low sulphur content of RDF is a desirable feature because sulphur dioxide emissions from kilns are subject to air pollution regulations and the use of a low sulphur fuel facilitates meeting these regulations. Also, sulphur is considered a contaminant of some products made in kilns (e.g., lime) and kiln operators prefer to minimise the addition of sulphur to their kilns.
In addition to the chemical composition of the RDF itself, the chemical composition of the ash resulting from combustion of RDF is also important. RDF and coal ash are similar in silica (Si02) and alumina (Ah03) content. RDF ash is generally lower in sulphur (S03) and iron oxide (Fe203) but higher in the alkaline oxides (Na20, K20) than coal ash.
Refuse Derived Fuel (combustible fuel waste) is classified as non-hazardous waste, not to be confused with municipal solid waste (MSW). The correct codes must be allocated for the correct export. According to the European Waste List (EWL), Refuse Derived fuel is listed as 19 12 10 (Fuel like combustible Waste). For international waste shipments outside the EU, RDF would require HS Code 3825100000.