Abstract:
Biogas production from organic fraction of municipal solid waste (OFMSW) not only helps in solid waste management but also
combat the food vs fuel dilemma. The presence of lignocellulosic material and other complex compounds in OFMSW hinder
biogas production. Therefore, pretreatment is an essential step to increase the hydrolysis rate by converting complex compounds
to simpler ones. This work was aimed at effective pretreatment of OFMSW by biological and thermo-chemical means. For
biological pretreatment lignin degrading fungal strains, Phanerochaete chrysosporium and Pleurotus ostreatus were employed.
Thermo-chemical treatment resulted in higher solubilisation yield in terms of sCOD and VFA making it a more effective method
as compared with biological pretreatment. The optimisation of thermo-chemical pretreatment was done by the Box-Behnken
design of response surface methodology (RSM). The interactive effect of influencing factors NaOH dose, temperature and time
were studied on the response of sCOD, VFA and phenolic content. The sCOD and VFA values were significantly increased by
increasing the NaOH concentration, temperature and time to a certain limit. The optimised condition from RSM for maximum
solubilisation yield in terms of sCOD, VFA and phenolic content was found to be NaOH dose of 4.72 g/L, temperature 180 °C
and time 30.3 min. Biogas production was increased by 169.5% after pretreatment at RSM optimised conditions as compared
with untreated OFMSW.
