Analysis of the Potential Use of the Anaerobic Digester to Treat the Food Waste at KDU Cadets’ Mess

Abstract

The global energy demand is on the rise while the resources are depleting in an equally high rate. Hence, it is of paramount importance to take measures to ensure that future generations have access to affordable and sustainable energy sources. “Biogas” is a clean and renewable source of energy that has the potential to reduce (especially in the rural sector) the use of fossil fuels that are depleting at a rapid rate, causing serious environmental problems. Furthermore, it provides a feasible option to reduce dumping of garbage without making any use of the same. Being a developing country, Sri Lanka could save foreign exchange outflow due to importation of petroleum products promoting renewable energy sources such as biogas. In this study, the biogas potential from different substrates found in the daily food waste from the Officer Cadets’ Mess of General Sir John Kotelawala Defence University (KDU) was investigated. The total waste generated has been found to be 351.9 kg per day, and the average biogas yield was estimated as 33,518.13 l/day. The average energy potential from biogas was identified as 724.032 MJ/day that would save the consumption of 16.84 kg of LPG on daily basis. Furthermore, it has also been identified that 40,000 kg of liquid bio fertilizer can be obtained from the existing 40 m3 digester installed at the University. It is estimated that the total potential savings per annum from the biogas plant for KDU is LKR 1,223,881.90 as per present economic status.