The waste world is perfecting one of the most natural biological processes that occur on this earth, Anaerobic Digestion, or AD if you’re in the know. I don’t know much about the human body’s digestion process, the extent of my knowledge goes something like this: I love food, I eat food, the food finds my belly and it’s digested there. Anaerobic Digestion of the leftover food waste that doesn’t make it into your belly isn’t much different from what goes on inside the human body.
I was lucky enough to attend a conference focusing on just this technology on November 17th. This workshop, hosted by the California Resource Recovery Association, brought together experts in the industry to discuss all aspects of Anaerobic Digestion. I was able to sit in on Scott Smithline’s presentation of Californians Against Waste. Scott started with a great analogy of AD as what goes on inside a Cow’s body. See laymen’s image below. Just like cow’s emit gas after digestion, so does AD, and that gas can be used to create renewable energy!
But, what really struck me about Scott’s presentation was the very important question he asked us to think about throughout the discussion. What problem are you trying to solve? What are your priorities? Whether you’re a developer, city or county, elected official, or someone who cares where their waste goes after it is pushed to the curb, this question is important.
These systems are great co-located at facilities that have multiple waste management functions. Another one of AD’s output is a solid residual material that is a great input for composting, and there is bound to be material like film plastics and sand and grit that can only go to a landfill. Placing AD at multi-faceted facilities limits the trucking of this material, which means less money spent on fuel and less greenhouse gas emissions!
If your goal is environmental and economic benefit, then one of the most important subsequent questions should be: Where am I going to put this thing? Existing infrastructure (read: transfer stations with sorting technology) and quality source separation collection programs with excellent customer education is a must! I’m going to bring us back to the human example for a second. Imagine your favorite deli sandwich, to go, wrapped in foil. Now imagine taking that first bite into the lunchtime goodness, only with the foil still intact. Instead of a post sandwich nap you’d be on a post sandwich trip to the hospital. In order for AD to work, and to get the highest energy value, consumers utilizing this technology must be cognizant of what they’re throwing in the organics bin (not to mention have an organics bin!).
Recology not only offers collection programs that educate consumers on how to separate their organics from other materials, we are constantly trying to find new ways to enhance our facilities to be more efficient and renewable. Keep an eye out; AD may be coming soon to a Recology facility near you!
