How to Have the World's Best Operating Anaerobic Digestion System

Presentation Description: Dave Parry will introduce the presentation and give an overview of achieving the best performing anaerobic digestion system. He will cover fundamental features of digestion design and operation for different processes including mesophilic, thermophilic, and thermal hydrolysis. He will introduce the microbial hydrolysis process (MHP) that can be added to any anaerobic digestion system to increase its performance to convert more organic solids to biogas. He will cover loading rates, capacity, and operating parameters. He will introduce digester shape, covers, construction, mixing, heating, foam and grit management. Dan Robillard will discuss the details of digester design for high performance and reliable operation. Examples of best practice in design will be given from several successful world-class anaerobic digestion projects. Comparison of digester shapes (pancake, silo, egg-shaped) and covers (floating and fixed steel, concrete) will be discussed. Consideration and comparison of mixing systems (gas, pumped jet, draft-tube, linear motion mixer, open impeller) will be presented. Maddy Fairley-Wax will discuss the details of enhancing anaerobic digestion with the MHP that uses a hyper-thermophilic bacterium, C. bescii, to enable the digestion of cellulose and other recalcitrant carbon compounds that otherwise wouldn't digest. She will present the results of pilot tests that demonstrated increases in volatile solids reduction (VSR) from good performance, VSR around 60 percent, to great performance, VSR greater than 75 percent. Biogas production increased proportionally to increased VSR. She will present the conceptual design for adding MHP to existing solids processing systems and the associated business cases. Adding MHP to well-designed anaerobic digestion systems will result in the best performing digesters in the world. Dave will then summarize the presentation, opening it up for questions and answers and facilitating the discussion on anaerobic digestion design, operation and performance. The timing will be Introduction 10 minutes, Detailed Design 20 minutes, Digestion enhancement with MHP 10 minutes, Q&A Discussion 10 minutes for a total of 50 minutes.