Manaf Farhan (1); (1) EMG International, LLC., Media, PA, U.S.A.


The brewing industry has made significant improvements over the past 20 years in water conservation. However, wastewater treatment and disposal remain a major issue that negatively impacts profitability and the environmental standing of breweries. As breweries have sought to improve their wastewater management practices, many have turned to digester systems, such as high-rate anaerobic digesters, for organics removal and energy generation. One of the leading technologies in this category is the anaerobic fluidized bed digester (AFBD) system with electricity generation and waste heat recovery. This system offers breweries an innovative and reliable wastewater treatment option that can provide significant cost savings, revenue from renewable electricity generation, and a reduction in environmental liability and carbon footprint. Following system installation and start-up, measuring and maintaining efficient long-term operation is critical to digester success and for achieving target return on investment (ROI). This paper discusses required system components, long-term performance data, operating costs and realized savings for a high-rate digester treating brewery wastewater. Digester system components discussed include digester units, flow equalization, solids removal, chemical and nutrient feed systems, instrumentation, biogas collection and conditioning, combined heat and power (CHP) and flare units, programmable logic controller (PLC) units, supervisory control and data acquisition (SCADA) units, and required plant utilities. Long-term digester system performance data presented include applied organic loading rates, organic removal efficiency, volatile organic acid (VOA) concentrations, biogas stream composition and generation rates, and pH and temperature trends. Digester system operating costs discussed include caustic consumption, wastewater heating, macro- and micro-nutrient addition, parasitic electric load, solids disposal, and required labor. Realized savings from the system include sewer surcharge savings, electricity generation, waste heat recovery, and available funding for reducing system capital expense cost. This paper is based on data and operational experience from an anaerobic fluidized bed digester system treating a craft brewery wastewater stream and producing electricity.

Manaf H. Farhan is the president and CEO of EMG International, based in Media, PA. He holds a B.S. degree in civil engineering from the University of Notre Dame, a master’s degree in environmental engineering from Columbia University, and master’s and Ph.D. degrees in systems engineering from the University of Pennsylvania. He is a licensed professional engineer. His doctoral research focused on design and optimization of various anaerobic digester processes to maximize process efficiency and biogas production. He has authored several peer-reviewed articles on anaerobic digestion and has served as an adjunct professor in the Department of Electrical and Systems Engineering at the University of Pennsylvania. He has over 20 years of experience providing a wide range of environmental engineering design and consulting services to private industry and governmental clients. His professional experience includes design and construction of digester systems for wastewater treatment and biogas and electricity generation for food and beverage facilities and for dairy farms; technical evaluation, process modifications, and operational support for various full-scale anaerobic digester installations; development and testing of bench-scale and pilot-scale wastewater treatment systems; pollution prevention and wastewater minimization audits; and biogas collection, clean-up, and utilization.