Method and apparatus for utilizing the heat energy of domestic and commercial refuse

Method of utilising the heat energy of domestic and commercial refuse in a kiln installation containing a kiln and a cooler arranged after the kiln, especially for the manufacture of mineral structural materials, in which

• (a) a light fraction is sorted out of the crude refuse as so-called fluff, is crushed and fed as prepared valuable material to a pyrolysis reactor in which this valuable material is degassed with air excluded and heat delivered, yielding pyrolysis gas and pyrolysis residues.
• (b) the pyrolysis gas is delivered to the main burner of the kiln, optionally with the additional use of primary fuel,
• characterised by the following features:
• (c) in order to obtain the valuable material, at least the crushed fluff is dried pneumatically to a dry substance content of at least approximately 78%, preferably approximately 88-92%, in a hot gas stream which is preferably branched off from the cooler of the kiln installation;
• (d) the valuable material thus obtained is fed to the pyrolysis reactor and degassed at low temperature, the pyrolysis reactor being indirectly heated with hot secondary air taken from the region of the junction between the kiln and the cooler and/or combustion gases from an auxiliary firing system or from the kiln;
• (e) the pyrolysis gas produced in the pyrolysis reactor, any quantity of primary fuel which may be necessary and the secondary air utilised for the indirect heating of the pyrolysis reactor are delivered to the main burner of the kiln.