Anaerobic Co-Digestion Biomethanation of Cannery Seafood Wastewater with Microcystis SP; Blue Green Algae with/without Glycerol Waste☆

Abstract We investigated the feasibility of using Microcystis sp; blue green algae (MB) as a co-substrate to improve the mesophilic anaerobic digestion of cannery seafood wastewater (CSW) supplemented with 1% (v/v) glycerol waste (GW), to maximize bio-methane production. The MB content was set at 5, 10 and 15% (v/v) to find a near optimal methane yield. The maximum 291 mL CH 4 /g VS-added methane yield, corresponding to 4.4 m 3 -CH 4 /m 3 - mixed wastewater, was achieved with a CSW: GW: MB mixture at the volumetric 94:1:5 ratio. The methane yield of CSW digested alone was 278 mL CH 4 /g VS-added (2.2 m 3 CH 4 / m 3 of wastewater). The yields from our other experiments ranged within 81– 150 mLCH 4 /g VS-added. Ratios of MB: CSW exceeding 5% (v/v) gave lower than optimal methane yields. The energy content of methane from 1 m 3 of mixed wastewater, with the near optimal mixture ratio 94:1:5, was 157 MJ or equivalently 44 kWh.