Plant Science Research, Vol. 41, 2019

Rice stubble as a potential bio-energy substrate

Stubble burning has greatly contributed to the rising air pollution and consecutively the health issues in India. The objective of this research was to conduct the bio-methane potential (BMP) assay of rice straw and convert the agricultural crop waste-to-energy (WtE). Batch experiments under anaerobic conditions were performed at 38 oC with rice straw and the inoculum was sourced from an industrial biogas plant. The total biogas production was continuously measured for 15 days with an ANKOM wireless gas production system. The experimental results demonstrated a biogas production of nearly 140 mL/g FM. Considering the thumb rule calculations, approximately 0.5 KWh electricity can be expected from 1 kg of rice straw. Post-digestion, the slurry from the anaerobic reactors where biogas is produced could be further utilized as organic fertilizers, further improving the organic content and quality of soil. The experiments demonstrated the possibility to generate energy from the otherwise discarded and wasted rice stubble as a sustainable alternative. Employing such residuebased biogas plants could not only generate a green energy, but can also provide farmers an incentive from the electricity and organic fertilizers produced and ultimately prevent the practice of stubble burning.