Thermogravimetric analysis of sewage sludge and straw co-firing

The main objective of this study is to perform thermogravimetric analysis on sewage sludge and straw co-firing at selected proportions. Sewage sludge is a residue from wastewater consisting of organic matter, toxic contaminants and heavy metals [1]. It is estimated that 10 million tonnes of sewage sludge are produced every year in European states, which represents 4.1% of all waste generated in the EU annually – about 250 million tonnes of dry solids [2]. Landfilling is deemed to be the most expensive way to dispose of sewage sludge, with average total costs ranging from EUR 260 to 350 per tonne of dry matter [3]. Straw is a major biomass solid waste from agriculture; it can be considered CO₂ neutral. The availability is wide in Europe that it is estimated to be 33 million metric tonnes [4]. A suite of thermogravimetric analysis and derivative thermogravimetric experiments was performed for this study, followed by the determination of the kinetic parameters and characteristic temperatures for these materials and their blends at different proportions. Through this analysis we can obtain information about the thermal behaviour, energy activation and ash content, and the decomposition of gaseous products can be identified the help of thermal decomposition [5].