TRASH: Part 2 - The Future of Solid Waste Management


This post is part of a two-part series on Solid Waste Management. In part one, we take a look at the history of waste management and how it’s currently treated in contemporary Canada. In part two, we take a look at some of the up-and-coming technologies of waste management, and the future of garbage.

Throughout history, societies have struggled to hygienically and sustainably manage their own waste. As green technology, clean energy and climate change become key factors in trash infrastructure, new technologies are gaining traction as sustainable waste management systems. Here are some of the most prominent new technologies making their way into the trash spotlight.

Energy Reclamation

“Reduce, reuse, recycle” has been recycling’s tagline for decades; but now, there’s a fourth “R”: Reclaim. Although lowest in the hierarchy, reduction is still the key to reducing landfill content; energy reclamation systems are popping up anywhere organic waste seems to be going to the wayside.

Currently, only two per cent of energy potential from solid waste is used in energy production. However, some organizations are hoping to change that. Enerkem and Zooshare are just some of the Canadian firms using converted waste to create synthesis gas through pyrolysis, an energy-reclaiming method that converts trash to gas. Zooshare uses organic waste from the Toronto Zoo (think: animal poo!) and converts it to biogas through the pyrolysis system.

First, solid waste has to be treated. It is heated in the absence or in controlled amounts of oxygen, and within seconds the material can “crack” and create a carbon-rich fuel. “Syngas”, or synthesis gas, is the clean and low-cost result: a fuel mixture of hydrogen, carbon monoxide and carbon dioxide. Syngas makes up 50 per cent of the density of natural gas and can be turned into all kinds of fuel. It is used to manufacture ethanol, methanol, ammonia, fossil fuel replacements, crude oil, and even green diesel fuel.
Syngas is a great use for biowaste, and the input is very important. Raw household garbage isn’t useable; a consistent sources of organic waste is needed. Yet grocery stores still continue to throw out more than 10 per cent of their food, which could potentially be used as a viable input material for syngas, if these systems were adopted.

Smart Bins

Several cities in the United States are adding RFID-enabled “smart bins” to their city’s streetscapes. You’ve probably seen RFID (radio-frequency identification) tags before; they’re on everything from library books, to Canadian passports, to medical equipment. By incorporating this technology into recycling bins, cities can monitor pick-up times, participation rates, and material data.

It also allows for “Pay-as-you-throw” fee structures, where garbage weight is charted throughout a route and individual houses are billed by how much they dispose. This doesn’t work in high-density areas though - apartments and condos often have communal garbage bins, making it impossible to track exactly who tossed what.

Incorporating RFID-enabled bins likely won’t do anything to change individual recycling rates. While the idea of being tracked may cause some residents to clean up their habits, the real benefit of smart bins is in real-time tracking and data collection. When and where are people recycling? Where are they not? What are the driving factors? Data analysis can help cities determine what is causing different diversion rates, and possibly how they can address them.

Green Plastic

Let’s start with regular plastics. They’re made from petroleum, they’re comprised of repeated long chains of molecules (polymers), and they’re really, really difficult to dispose of. Burning them gives off toxic chemicals. They take about 500 years to decompose in landfills; by estimates, we assume, since plastics have only been around for about a century. In the United States alone, more than 200,000 barrels of oil are used every day to make plastic packaging.

As far as “environmentally-friendly” plastics go, they usually fall into one of three categories: bioplastics, biodegradable plastics, and eco / recycled plastics. Recycled plastics are simply re-used plastics, rather than raw manufactured materials, and take just as long to degrade as your neighbourhood grocery bag.

Biodegradable plastics are also made from petrochemicals but are engineered with additives to break down more quickly, usually in the presence of oxygen and moisture. While they do break down more easily than traditional plastics, they don’t break down harmlessly. Sometimes, they can decompose into residue that is toxic for plants and therefore unsuitable for composting.

The last type, bioplastics, are the only type made from biomass or organic material. Derived from sources like vegetable fats, corn starch, or microbes, these materials can be found as packing peanuts, some food packaging, and teabags.

While biodegradable plastics with their lowered carbon footprint and in-house compost potential seem like a great idea, very few will ultimately degrade in your compost bin. To be considered truly biodegradable, the plastic needs to decompose into carbon dioxide, methane, water, inorganic compounds or biomass, in a specific period of time. Unfortunately, very few commercial plastics meet the criteria.

E-Waste

Electronic waste is one of the fastest-growing pollution sources in the world. When not properly disposed of, it can be a serious threat to human health and the environment.

The government of Canada has a comprehensive e-waste strategic plan (http://www.tpsgc-pwgsc.gc.ca/ecologisation-greening/dechets-waste/index-eng.html) that emphasizes re-use and donation for old electronics, but cities have recently enacted their own e-waste recycling systems.

The Waste Electrical and Electronic Equipment, or "WEEE"- system, recycles 95 per cent of material by weight, and even thoroughly destroys all data left on old electronics. First, items are sorted by hand and materials like copper or batteries are removed (Note: Toronto’s electronics recycling program and many others, do not recycle batteries, which instead must be dropped off at hazardous recycling depots). The rest is then shredded and thinly spread so overhead magnets can pull steel and iron from conveyors. Metallics are separated and sold as raw materials, and then water separation splits the remaining plastics from glass. Once divided, materials are melted or shredded and resold.

The system itself works pretty well, however the main issue is getting consumers to recycle their electronics. Old electronics are generally thrown out with household waste, despite growing efforts to market electronic disposal centers across Canada. The City of Toronto even offers curbside electronics recycling, as long as it’s clearly separated from the rest of the household material.

Interestingly, the future of waste management is a huge conglomeration of technology, governance, city ordinances, and good old-fashioned neighbour-shaming. Groupthink plays a massive role in how neighbourhoods and municipalities treat their waste. So far, Toronto does a relatively good job in waste management, due to strict municipal policies and expensive fees for high volumes of garbage. But there’s still a long way to go. Fortunately, there are so many advances in green waste systems that are gaining traction throughout the world. As newly-made waste reduction targets are met, we’ll be able to see how these technologies can improve the landfill structure and help make our cities much less wasteful.