Electrical and Microwave Characterization of Thermal Annealed Sewage Sludge Derived Biochar Composites

Ever-increasing proportions of sewage sludge are being generated due to increases in population and urbanization. As a result, the disposal of sewage sludge for use as manure and for other agricultural applications is not sufficient. The use of biochar derived from sewage sludge as a substitute to other carbon fillers was analyzed by performing electrical and morphological characterization. The electrical and microwave characterization of composites filled with sludge biochar was performed. Thermal annealing of biochar makes it conductive and suitable for a variety of electrical and microwave applications. Composite samples of a thickness of 4 mm with 20 wt.% of sludge biochar provided a shielding effectiveness value of almost 10 dB.