June 19, 2014
In my previous column, I focused on the growth of Anaerobic Digestion (AD) in the United States and how AD is attractive for processing putrescible organics because it harnesses renewable energy from organics, provides a high degree of odor control and produces a solid digestate that can be composted to produce value-added soil amendments. AD’s growth has been slow, but has increased steadily over the past few years.
Expansion of AD capacity and infrastructure were recently discussed in detail at the Second Annual Composting and Organics Recycling Conference Program at WasteExpo in Atlanta. Speaking to an audience of over 200 attendees, more than a dozen speakers focused on public, private and public-private partnerships in AD as well as barriers to growth and solutions to key problems affecting the feasibility of processing organic materials for energy recovery. Integrated perspectives on organics management allowed speakers to examine the extraction of biogas from organics using anaerobic digestion (AD), the composting of residuals, the creation and marketing of the renewable energy from AD and the value-added soil amendments from composting.
The organics management industry is growing, which is evidenced by the policies and programs that are being implemented to increase organics diversion from landfills–especially food residuals; composting and AD technologies that are available to process these materials and convert them into value-added products and the lack of organics infrastructure in certain geographic areas, which poses a challenge the industry must resolve and necessitates the development of tools to identify capacity needs.
This topic was the theme of the WasteExpo session, “Infrastructure Status, Needs and Development in the Organics Industry.” Policy changes and opportunities for organics in Massachusetts and Vermont were discussed by Jen McDonnell from Casella Waste Systems Inc., which is based in Vermont, where state legislation is a primary driver for increasing the organics infrastructure needed to divert food residuals from the landfills. In 2012, Vermont passed a phased-in ban on the disposal of food waste. By 2020, disposal facilities will no longer accept food residuals.
This year, Massachusetts added commercial organics to its existing waste ban regulations in order to keep them out of landfills and incinerators. It appears that in Massachusetts there is enough statewide capacity either in place or under development, but there may be regional gaps. In Vermont, sufficient infrastructure exists through 2015. By then, it is expected that additional facilities will be developed and existing facilities will expand to meet the need for processing via composting and/or AD. Both states initially identified collection as a barrier, but several haulers already collect food and others are getting into the business. Similar legislation has been introduced in Connecticut and Rhode Island.
As with many organics advocates, the Michigan–based consulting firm Resource Recycling Systems (RRS) views the abundance of organics that go into the landfill as a wasted opportunity. Aaron Burman from RRS discussed the development of GIS Tools for identifying infrastructure availability and shortfall. This can be accomplished by estimating residential, commercial and industrial organics currently being landfilled, and comparing the data to the existing organics infrastructure, which can be gleaned from state and other sources.
One of the barriers to developing the needed infrastructure may be its inherent paradox. A critical mass of material is needed to develop processing facilities while, at the same time, those facilities are needed for efficient material collection routes.
Perhaps more states should follow the lead of Massachusetts and Vermont. Existing capacity will be utilized and developed to meet the needs of organics processing. In California, San Francisco has been successfully diverting its organics for years. Jo Zientek presented the City of San Jose’s organics diversion and zero waste programs and Eric Herbert of Zero Waste Energy discussed San Jose’s AD and composting projects.
With more than 3,000 yard waste-composting facilities in the United States, the most logical way to increase capacity quickly is to add food residuals to existing yard waste composting facilities. A dedicated session devoted to this topic discussed collection practices, public and private operator’s perspectives, regulatory issues and best management practices for incorporating food residuals.
Stuart Buckner, Ph.D., is president of Buckner Environmental Associates LLC, a consulting firm specializing in organics management.