As a result of microbiological treatment, municipal sewage treatment plants generate large amounts of sewage sludge. One of the possible uses of sewage sludge is its thermal treatment in combustion plants, for which the sludge must be pre-compacted and dried to approximately 90 percent of dry matter content. The advantages of combustion are primarily the reduction of sludge mass, the destruction of hazardous organic matter and the ability for energy recovery that can be used for drying process. In this master's thesis, we created a laboratory combustion device that allowed us to perform measurements of sludge combustion under different conditions. The measurements were performed at different temperatures and humidity ratios, with different temperatures of primary air. The laboratory combustion device was based on a fixed grate, batch combustion and a counter-current supply of air and fuel. The thermodynamic parameters and the composition of the flue gases in the primary combustion chamber were determined and a database of experimental data was constructed for the purpose of validation of the numerical models. The data and the analysed results can thus be used for model development and design of combustion plants on a larger scale using a moving combustion grate and allowing continuous combustion. The results confirm that sewage sludge can be used as fuel, without taking additional measures to increase its heating value.
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