Bioresource Technology, Vol.267, 281-290, 2018
Novel insights into scalability of biosurfactant combined microwave disintegration of sludge at alkali pH for achieving profitable bioenergy recovery and net profit
In the present study, a novel alkali rhamnolipid combined microwave disintegration (ARMD) was employed to achieve net energy production, increased liquefaction and to increase the amenability of sludge towards bio-methanation. Additionally, biosurfactant rhamnolipid under alkali conditions enhances the liquefaction at alkali pH of 10 with a maximal liquefaction of 55% with reduced energy consumption (1620 kJ/kg TS) than RMD (45.7% and 3240 kJ/kg TS specific energy) and MD (33.7% and 6480 kJ/kg TS specific energy). A higher bio-methane production of 379 mL/g COD was achieved for ARMD when compared to RMD (329 mL/g COD) and MD (239 mL/g COD). The scalable studies imply that the ARMD demands input energy of -282.27 kWh. A net yield of (0.39 USD/ton) was probably achieved via novel ARMD technique indicating its suitability at large scale execution when compared to RMD (net cost-31.34 USD/ton) and MD (-84.23 net cost USD/ton), respectively.
Keywords:Dairy waste activated sludge;Microwave disintegration;Biosurfactant;Specific energy;Biomethane;Energy analysis