Synergistic analysis on novel biosurfactant-induced mechanical pretreatment for energy-efficient biomethane production from organic waste

Abstract

In this work, the potential of food waste as a sustainable substrate for biomethane production was investigated, along with its disintegration using rotor stator homogenization pretreatment (RSHP) and surfactant coupled rotor stator homogenization pretreatment (SCRSHP). Initially, RSHP was optimized, and then, in the optimized RSHP condition, SCRSHP was performed by induced alkyl polyglycoside (APG) surfactant in the sample at various dosages, and it was optimized. SCRSHP achieved 19.3 % solubilization at 1053 μL/kgTS surfactant dose, with a pretreatment specific energy consumption (PSEC) of 117.5 kJ/kgTS, surpassing RSHP's 12.2 % at 293.7 kJ/kgTS. The decrement in PSEC of 176.2 kJ/kgTS and increment in solubilization of 7.5 % was due to the effective action of APG surfactant. At the optimized pretreatment condition, SCRSHP samples obtained a higher biomethane production of 169 ml/gCOD compared to UTS (49 ml/gCOD) and RSHP (115 ml/gCOD) samples. Energy analysis displayed that SCRSHP showed an energy ratio of 1.75, higher than RSHP of 0.53. The above findings revealed that the APG has a positive synergetic impact on RSHP, and further, the high energy ratio of SCRSHP confirms its suitability for practical application.