Characterisation of the properties of alternative fuels containing sewage sludge

The paper presents the characteristics of the fuels which were prepared with the use of sewage sludge and other waste materials. Applicability of those fuels was analysed in the coal co-combustion processes, and in particular in the cement clinker manufacturing process.Three types of sludge-derived fuels were subjected to comparative analyses: the fuel which was prepared with the use of sewage sludge and coal slurry (PBS fuel), that involving sewage sludge and meat and bone meal (PBM fuel), and that in which sewage sludge was composed with sawdust (PBT fuel).Physical and chemical properties of those fuels were investigated, with special attention paid to their calorific values and physical properties.The results showed that the fuels manufactured with the use of waste materials offered the energy values which were satisfactory for the cement industry as specified for alternative fuels in that branch. The tests for physical properties revealed that such fuels may be subjected to mechanical handling operations in the transport and storage processes.