Innovation Portfolio Management for Retrofitting Advanced Biotechnologies for Anaerobic Digestion Process at Lulu Island Wastewater Treatment Plant

Metro Vancouver recently commissioned the Pilot Digestion Optimization Facility (PDOF) at its Lulu Island Wastewater Treatment Plant (LI WWTP) to facilitate the evaluation of different digestion optimization technologies without risk to full-scale plant operation. This study summarizes the integrated approach adopted at the pilot-scale preliminary design stage for two of these technologies. The first technology aims to increase biogas production rates by testing the Direct Interspecies Electron Transfer (DIET) process using electroconductive materials. The second technology utilizes a biological hydrogen methanation (BHM) process to convert the carbon dioxide portion of biogas into renewable natural gas (RNG) using hydrogen. Cost-effective pilot-scale conceptual designs are developed for testing the in-situ and ex-situ configurations of these technologies in order to reach a go/no-go decision quickly, while still producing replicable results for further scale-up. To guide the decision-making process for selecting these technologies for pilot testing, GHG emission reduction calculations and an energy balance model are used to evaluate the environmental impacts of implementing these technologies at full-scale. A Sumo model is used to evaluate the effects of implementing these technologies on process intensification.