Gaseous emissions during concurrent combustion of biomass and non-recyclablemunicipal solid waste

摘要

Background: Biomass and municipal solid waste offer sustainable sources ofenergy; for example to meet heat and electricity demand in the form of combinedcooling, heat and power. Combustion of biomass has a lesser impact than solidfossil fuels (e. g. coal) upon gas pollutant emissions, whilst energy recoveryfrom municipal solid waste is a beneficial component of an integrated,sustainable waste management programme. Concurrent combustion of these fuelsusing a fluidised bed combustor may be a successful method of overcoming some ofthe disadvantages of biomass (high fuel supply and distribution costs,combustion characteristics) and characteristics of municipal solid waste(heterogeneous content, conflict with materials recycling). It should beconsidered that combustion of municipal solid waste may be a financiallyattractive disposal route if a 'gate fee' value exists for accepting waste forcombustion, which will reduce the net cost of utilising relatively moreexpensive biomass fuels. Results: Emissions of nitrogen monoxide and sulphurdioxide for combustion of biomass are suppressed after substitution of biomassfor municipal solid waste materials as the input fuel mixture. Interactionsbetween these and other pollutants such as hydrogen chloride, nitrous oxide andcarbon monoxide indicate complex, competing reactions occur betweenintermediates of these compounds to determine final resultant emissions.Conclusions: Fluidised bed concurrent combustion is an appropriate technique toexploit biomass and municipal solid waste resources, without the use of fossilfuels. The addition of municipal solid waste to biomass combustion has theeffect of reducing emissions of some gaseous pollutants.