Manufacturing of biogas from digested paddy staw using delta - D technology

Abstract

Anaerobic digestion is commonly used for waste water treatment. Technologies have been introduced and new technologies are being developed to generate biogas by anaerobic digestion oforganic waste,as an integrated solution for waste treatment and for energy production from waste. Being an agricultural country, Sri Lanka generatesover five million metric tonnes of rice straw (RS) per annum as a by-product in the cultivation of rice. Currently RS is dumped or burnt without converting it to a productive output.One productive output that can be produced is biogas. National Engineering Research and Development Centre (NERDC) is one of the main state owned research and development (R & D) organisations, that has developed a patented technology, well known as Dry Batch Biogas Technology, to generate biogas by anaerobic digestion of RS. However, due to several technical and economic reasons (Alwis A, et al, 1997 and Perera S.A.S, 2001) manufacture of biogas from RS has been abandoned. Professor S.A.S. Perera, Professor of Chemical and Process Engineering of the University of Moratuwa, has developed a patented technology, well known as Delta-D Technology (DT), by which most types of organic waste can be rapidly digested into organic fertiliser, by using a patented digestive fluid called Delta-D. Currently DT is being used to convert fibrous RS into a powder, within 1 day, using DT. In this study,experiments have been done to explore the possibility of biogas production from RS, digested by DT. Two experiment set up were conducted to do comparison of biogas production of digested rice straw and untreated rice straw.