Thermal pretreatment of Lantana camara for improved biogas production: Process parameter studies for energy evaluation

The rigid lignocellulosic structure of Lantana camara impedes the hydrolysis phase and reduces the biogas production during anaerobic digestion of Lantana camara. Hence, the current study focuses on the impact of various heating pretreatment techniques, viz., hot air oven (HAO), autoclave (ATC), hot water bath (HWB), and microwave (MCW) on L. camara to speed up hydrolysis and boost up biogas production. ATC pretreatment of L. camara was witnessed to be most efficient compared to HAO, MCW, and HWB pretreatment. ATC pretreatment enhanced the solubilization (45.44%), and an increment in volatile fatty acids (VFA) was observed (56.75%) at 110 degrees C for 80 min when correlated to the untreated (control). Cumulative methane production following ATC pretreatment had risen to 3656 mL in 5 weeks from 2895 mL in 7 weeks. Thermal pretreatment of Lantana camara broke down the rigid lignocellulosic structure, accelerating the hydrolysis stage and improving biogas production simultaneously. To the best of our knowledge, this is the first thermal pretreatment study conducted on Lantana camara for biogas production.

Automated summary

The study investigates the impact of different heating pretreatment techniques on Lantana camara to accelerate hydrolysis and enhance biogas production. Autoclave pretreatment was found to be the most efficient. It increased solubilization (45.44%) and volatile fatty acids (56.75%) at 110 degrees C for 80 min compared to the untreated control. Cumulative methane production increased from 2895 mL in 7 weeks to 3656 mL in 5 weeks following autoclave pretreatment. Thermal pretreatment of Lantana camara breaks down the rigid lignocellulosic structure, improving hydrolysis and biogas production simultaneously. This is the first thermal pretreatment study conducted on Lantana camara for biogas production.