ENHANCING BIOGAS PRODUCTION BY THERMAL PRETREATMENT OF AGRICULTURAL WASTES

Developing countries are suffering from many problems such as shortage in energy and electricity in addition to increasing wastes that cause high pollution. Biogas production is gaining increasing attention worldwide to avoid global warming, increasing energy security and the need for sustainable waste management. So the aim of the present study was enhancement of biogas production by using thermal pretreatment for the agricultural wastes. A laboratory scale bioreactor made from plastic, 8 liter capacity, was used in this research. Three different mixtures were used (100% cattle dung (CD), 50% CD + 50% BS, and 100% bagasse (BS)). The samples were heated in a furnace at 175 ᵒC, and 200 ᵒC. The samples were subjected to heat for three different durations 20, 40 or 60 min. Also samples were partially heated at four levels, 25%, 50%, 75% and 100%. The results indicated that the maximum daily biogas production, accumulative biogas production and methane production related to volatile solids mass (VS) were 732.4,15475.5 L/kg VS, and 577.9 LCH₄/Kg VS respectively for the second fermentation mixture (50% CD+ 50% BS) and 60 min heating time using temperature of 175 °C. But the maximum calorific value was 7241.7 kCal/ m³ for the third fermentation mixture (100% BS) using temperature of 200 °C for 60 min and 100% heating of samples.