Special Guest Seminar Environmental Engineering Iowa State University

Special Guest Seminar Environmental Engineering @ Iowa State University …with special emphasis on… Autothermal Thermophilic Aerobic Digestion (ATAD) Processing James E. Alleman, Professor and Chair Civil, Construction, and Environmental Engineering, Iowa State University (Ames, IA, USA) This special seminar will present an overview of environmental engineering underway at Iowa State University, and a special focus on ATAD sludge processing at thermophilic temperatures (i. e. , typically ranging from 35 o to 75 o. C). This latter ATAD concept has drawn increasing attention in the past two decades based on projected benefits with accelerated solids breakdown and advanced pathogen kill levels. This portion of the seminar will accordingly provide an overview of the historical evolution of this technology, and a state-of-the-art examination on the involved mechanisms plus hardware. In addition, specific technical issues experienced by ATAD (i. e. , autothermal thermophilic aerobic digestion) systems will be reviewed, covering such aspects as oxygen transfer plus process monitoring and control challenges, energy demand, foam generation and mechanical breakdown, off-gas (ammonia, sulfide, and mercaptan) emission and downstream treatment. Multiple case study examples will also be presented to demonstrate particular aspects of real-world ATAD operation in relation to various ATAD vendor design options.