High rate biomethanation technology for solid waste management and rapid biogas production: An emphasis on reactor design parameters

• A novel high rate bio-methanation digester was designed and operated.
• Digester performance was evaluated with real field composite food waste.
• High reduction of total solids was achieved with removal efficiency of average 94.7%.
• Overall performance analysis showed feasibility and efficacy of the designed digester.

A high rate biomethanation digester was designed and fabricated to study its real field treatment efficiency and simultaneous biogas generation. The major design parameters like self mixing, delinking hydraulic retention time and solid retention time etc. were considered for efficient performance. It was operated with an organic loading rate (OLR) of 1.5 kg/m3 d−1 with composite food waste for about one year. The maximum treatment efficiency achieved with respect to total solid (TS) reduction and volatile solids (VS) reduction was 94.5% and 89.7%, respectively. Annual mean biogas of about 0.16 m3/kg VS d−1 was observed with methane content varying from 56% to 60% (v/v). The high competence of high rate digester is attributed to its specific design features and intermittent mixing of the digester contents and also due to the hydrodynamic principles involved in its operation.