Luis Enrique Lambis Benitez
Stanford University School of Medicine,Colombia
Title: Performance and stability of rapidly degradable anaerobic digestion waste: Kitchen waste case study
Biography
Biography: Luis Enrique Lambis Benitez
Abstract
The management of food waste is a challenging task due to its special nature of high moisture content and easy decay. Anaerobic digestion has been proven an efficient and green technology in disposing of different natures wastes. Anaerobic digestion of rapidly biodegradable waste, like kitchen waste, is limited by the amount of organic load the system can withstand without inhibited. In this sense, the feasibility of this technology depends on finding strategies for giving the substrate stability. To counteract the inhibition and to overcome the disadvantages in single digestion, co-digestion of food waste with Cattle manure was carried out. Organic load and mixture ratio were selected as key parameters in order to improve process stability and performance. A 22 factorial design was used to analyze the effect of the selected key parameters, using as levels: 10-17 g of volatile solid/l and 50:50 – 90:10 (in terms of volatile solids), for organic load and mixture ratio respectively. Anaerobic reactors were carried out in triplicate using 50 mL hermetically closed bottles at 39 ± 2 °C. A blank was used to determine the background methane yield of the inoculum. A mono-digestion control (only kitchen waste as substrate) was used as well. Methane volume production and volatile solid consumption were performance response variables. Total volatile fatty acids / Total alkalinity ratio and pH were stability response variables. The maximum methane yield of 0.94 m3 CH4/kg VS was obtain by reactors with a organic load of 10 g VS/l and 90:10 mixing ratio kitchen waste/ cattle manure. An increase of 29% compared to mono-digestion.