I asked GBB’s newest addition, Lori Scozzafava, what her take is on creating renewable energy from waste. Lori said, “First, be realistic about the portion of the waste stream that can be recycled. Then, build markets based on the recovered materials. And, finally after recycling as much as possible, recover energy from what’s left!”
With Lori’s thoughts in mind, I’ll start by being realistic about the portion of the waste stream that is now and will continue to be recyclable. In the U.S., market forces, advancements in technology, and know-how have made it possible to recycle 34 percent of the waste stream (more than 80 million annual tons of marketable materials) into products and packaging.
Policies, programs and research on organics show promise that an additional 30 percent of the waste stream possibly can be removed and recycled.
Composting technologies are developing from traditional yard debris windrows and turning into more complex static pile approaches that are suitable for a wider variety of materials, including food waste.
Anaerobic digestion (AD) will further expand our capabilities to process organics to make energy or fuel as a byproduct. The dross from AD, digestate, can be processed further into organic soil amendments and fertilizer products. But, even after aggressive recycling, including more food waste recycling or recovery, perhaps 30 to 40 percent of the waste stream will remain that needs to be managed.
So, is this the point where we should stop looking toward getting more out of the waste stream? The answer lies in looking at what’s left.
The concept is already at work in many American industrial campuses, factories and cement kilns. Solid waste managers should pay attention. These companies want to say to their stockholders, customers and employees that they have embraced sustainability. A major component of that effort is zero waste to landfill (or ZWL).
Companies adopt these goals themselves, and some go so far as requiring their suppliers to do so, too. So their will is there. Their manufacturing systems have adapted. But they face the hardest challenges when they find limited capacity to recover resources after they have reduced, reused and recycled.
Therefore, as the industry contemplates how to revise processing systems, expand the infrastructure for AD, and adjust to the shrinking commodity market, we can’t forget to recover the fuel and energy value in the remaining waste, too.
And, how do we create a circular materials management economy by fostering integrated networks of generators, processors and buyers, and back around again?
One way is to combine the needs of recycling and recovery through the implementation of regional environmental resource recovery parks. These networks, which can be co-located on a campus or be regional, consist of industries that convert waste streams into commodities and recyclables, recyclables into products and packaging, and products into economic power.
They, themselves, can be driven by refuse-derived fuel (RDF) or waste-to-energy (WTE) combined heat and power (CHP). Imagine waste and recycling trucks unloading, next filling up with bio-CNG (compressed natural gas), and factories rolling out products bearing labels that proclaim: “Made in the U.S.A., by you and with your recyclables!”
Harvey Gershman is president of Gershman, Brickner & Bratton Inc., solid waste management consultants, firstname.lastname@example.org.
Inspiration and research assistance provided by Lori Scozzafava, vice president, Kate Vasquez, senior consultant, and Eric Weiss, consultant I.