Determination of biomass content in combusted municipal waste and associated CO2 emissions in Estonia

Abstract Incineration of mixed municipal waste is gaining increasing importance in many European countries. This is also the case in several European Union member states such as Estonia, where waste-to-energy technology provides a relatively fast option to meet the demanding EU waste management targets regarding municipal waste recovery and landfilling. Furthermore, the biomass fraction of municipal solid waste, when used as a fuel for energy production, is recognised as a renewable energy source and is therefore eligible for government subsidy under Estonian legislation. Also CO 2 emissions are accounted for according to their source, either as biogenic (resulting from the biomass fraction of the waste), and thus climate neutral, or as fossil, and thus liable for CO 2 charges. Therefore, it is crucial that operators of waste incineration plants are able to determine the ratio of biogenic and fossil carbon in combustible waste. This paper summarises the results of the research conducted in the first waste incineration plant in Estonia and the Baltic States to determine the material composition (incl. biomass content) and the proportion of fossil CO 2 emission from combusted mixed municipal solid waste. The results of a one year long manual waste sorting study and laboratory analysis show that the share of the biomass fraction is approximately 52 % in the combusted municipal solid waste (on a dry weight basis) and that fossil carbon accounts for about 40 % of the total carbon (on a wet weight bases). The associated annual average fossil CO 2 emissions are about 429 kg per ton of combusted municipal waste.