Biodigestion of Mixed Substrates of Cow Manure-Delignified Spent Coffee Ground (DSCG) using Microorganism Enhancer for Biogas Production and Its Kinetic Study

Environmentally benign energy strategies have been implemented to cope with the rapidly increased global needs. Indonesia’s coffee consumption has triggered an increase in generation of spent ground (SCG) that can be used as a biogas raw material. The novelty we offer this research effort is reduce premature formation biogas, so extend production period during digestion by adjusting right pH and time. This study aimed produce from organic substrate mixture containing cow manure SCG 25:1 C/N ratio employing effective microorganisms-4 (EM-4). process began delignification using sodium hydroxide solution obtain delignified (DSCG). biodegradation was performed anaerobic batch (AD) system at ambient temperature varying (5, 7, 9) EM-4 concentration (6%, 9%, 12%). product chemical oxygen demand measurements were carried out every two days for 60 digestion. results showed induced earlier initial enhanced volume, extended 7 level 9% loading gave ideal condition 11.28 mL biogas/g COD 100.2% enhancement. modified Gompertz equation fitted experimental data very well indicated high value coefficient determination (R2 > 0.95).