Effects of physical and chemical pretreatment on biogas production potentials of different waste types

Developed and developing countries are facing serious challenges in managing their rapidly increase in waste generation. Solid waste management has become a major issue in the last decade due to environmental and economical concerns. Biowaste pretreatment is a growing research area with new strategies appearing. The purpose of this research is to evaluate the anaerobic digestion of apple pomace and waste activated sludge waste in terms of pretreatment. In this study, main pretreatment strategies for sample include: ultrasound (35 and 53 kHz), thermal and chemical (pH<2, pH 5 and pH 10). Two factors were samples of different temperature (25,40,50 and 60 °C) and operation time (5,15,30,45 minutes) for each pretreatment method. The effects on pretreatment were investigated by measuring changes in the soluble protein concentrations of pretreated wastes and the enhanced anaerobic digestion was determined by using biochemical methane potential (BMP) assay. It was observed that the temperature and operation time have an enhancing effect on various pretreatments, and in some cases it has an inhibitory effect on the increase of BMP. In this study, the effectiveness of certain pretreatment methods on methane increase has been proven.