Current State of Anaerobic Digestion of Organic Wastes in North America

With the large volumes of organic waste produced in the USA each year (78.7 million tons of organic municipal solid waste, 335 million tons of animal manure, and 130 million tons of biosolids), there is potential to develop a viable biogas industry via anaerobic digestion (AD) that can boost the economy and provide a reliable, distributed source of renewable energy while reducing greenhouse gas emissions. AD is a better practice for organic waste management than the current practice of landfilling or incineration. Since 2013, US public policy and market conditions have been looking increasingly favorable for the development of AD of organic waste. Some of the main barriers to commercialization of an AD industry include highly variable organic waste characteristics and volume, process economics, biogas cleanup requirements, policy, and public acceptance. This paper discusses new technologies to overcome these barriers with case studies from successful companies in the USA.