Biogas production from banana stem waste: optimisation of 10 l sequencing batch reactor

The performance of biogas production using banana stem waste in anaerobic system was investigated. Mixed culture for this study was from banana plantation soil and acclimatized in anaerobic condition. The performance was tested under the conditions of various temperatures (26degC-40degC), organic loading rates (OLR) (0.4 g TS/l.d-2 gTS/l.d), and hydraulic retention times (HRT) (3 d-20 d). Conditions for temperature, OLR and HRT in this study was based on the best range obtained from literature review The optimization test was done using design-expert software version 6.0.4 was utilized in this research to design the experiments and optimize the system. It was found that for maximum biogas yield the levels of the variables are as follows: temperature = 35.8degC, OLR = 1.42 gTS/l.d and HRT = 11.7 d. Experiments conducted with these optimised levels of variables gave an average biogas yield of 1.95 l/g COD. Factor analysis to both system discovered that all factors studied (OLR, HRT and temperature) gave significant effect to biogas production process.