September 23, 2023

Toward the New Hierarchy

It seems so pointless to throw our National Resources into a hole and pay to keep them there, just to once again pay to put virgin resources back into the one-way flow of our supply chain. Yet anyone who has been witness to indiscriminant “trashing” of our environment understands that today’s best management practices are a grand improvement over past calamities.

If the only goal is to reduce the volume and toxicity of that residual waste, sanitary disposal can be managed through state-of-the art landfilling, or by incineration, where wastes are “rendered to ash”. But incineration is still a form of disposal, and Disposal does not recover the resource, only places it permanently “out of the way”. What a waste.

We have means now to carefully “un-bake the cake” of that complex residual waste accumulation with a variety of methods we might recognize collectively as reverse manufacturing. These processes disassemble waste components at the molecular level, and prepare the foundation resources to be remanufactured into New Goods. When this ability is properly used as a last-resort instead of disposal in an ordered Waste Management Hierarchy, molecular reclamation can be called Recovery.

The European Union recently modified their Waste Management Hierarchy. They have now officially added a fifth step of preference in their overall schema for waste-management-by-choice: Reduce, Reuse, Recycle… Recover… Dispose. Logic prevails; hopefully, our own national common sense will follow suit.

The lines are drawn, but the fine gradations between these Waste Management Hierarchy steps tend to represent a continuum, instead of offering clear and discrete categories of action.

What is “Recovery”, and how may this step be accomplished cleanly and economically? What must we do to firmly establish this paradigm not just in institutionalized law, but also more broadly as a universal part of our social and industrial infrastructure?

Conversion for Optimal Recovery

Conversion of discarded waste materials at the molecular level for recovery of intrinsic resources requires two parts: (1) the technology by design must allow access to intermediary products, such that those chars, liquids and/or gases can be sampled, characterized, and modified as needed to result in ultra-clean final products; and (2) this process of interception, characterization and modification must be accomplished by operational mode, such that the information feed-back loop that intermediary sampling facilitates is actually acted upon.

A decade ago, requirements for real-time sensoring and computer analysis of the intricate changes occurring within the explosive reactions of a thermal treatment unit were far too expensive, requiring massive data handling capabilities not available outside universities and military facilities. Today, small and inexpensive computers can assimilate those same data, the algorithms can be applied, and the resulting analyses become feed-back for programmable logic controls (PLCs) directing the moment-by-moment operation of the equipment.

Energy is the underlying requirement, when molecular bonds are to be separated. The surrounding molecules must be sufficiently energized to overcome the strength of each bond to be disassembled, and the input amount varies depending on that inherent bonding tenacity. That energy can be introduced in a number of ways, some better suited to managing specific waste residuals than others. Some resources hold more molecular-level value than others in the marketplace. The market will naturally promote cost-effective recovery. Those that believe an economy should be solely market-based might argue that this guideline should be sufficient. Yet cheaper is not necessarily better.

Some methods for energizing and breaking molecular bonds are more costly than others. Technical designs and modes of operation that can effectively recovery resources from homogenous waste types may not be sufficiently robust for highly heterogeneous feedstock. Technical specifications become important, defining “envelopes” of design and operation according to the input, and the intended end-product. Permitting processes guide proper usage, and implement restrictions on use of the wrong tool for the job at hand. These checks on the market forces need to be constructed only where optimization for cleanliness and percentage recovery trumps the underlying economics.

As the molecular diversity of the feedstock increases, the nature of bonds requiring deconstruction also varies. Some of the most toxic residuals are also the most difficult to devolve; to maximize environmental cleanliness, the conversion process must be optimized to effectively reduce these most reticent fractions to their non-toxic constituents. Environmental concern must drive Conversion Technology design and operation toward both maximum recovery of resources AND maximum reduction of toxicity; these responses to appropriate environmental concern become performance standards.

Many of the technologies available for conversion of waste into recoverable resources have been around for half a century or more. Our industrial ability to design, operate, monitor and modify the process “on the fly” is only now able to meet our modern and ever-tightening standards of environmental cleanliness. Design and operational control advances allow conversion operations to be scaled to fit within our communities. Conversion of wastes at the source (rather than regionally) can dramatically reduce shipped volume and weight, thus minimizing both cost and impact of transport. Community-scaled, ultra-clean conversion of post-recycling municipal solid waste residual for cost-effective recovery of our natural resources: this is new. And because it is new, much remains to be developed to define, and to ensure, proper integration within this shifting paradigm that now informs our Waste Management Hierarchy. Cost recovery

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