Published: February 26, 2007

Waste not…

Published: February 26, 2007

PATRICK MOORE
February 26, 2007

While it may be a long way from sexy environmental solutions like hybrid cars and gently spinning turbines of pastoral wind farms, the importance of managing our waste is a central piece of Canada’s sustainability puzzle. The fact is, there is a real need for Canadians to update their views on waste and what we should do with it.
After all, we produce more than 30 million tonnes of waste in a year. Thirty-one per cent of it comes from the residential sector while 69 per cent comes from the industrial, commercial and institutional sector and the construction and demolition sector. We need to take better responsibility for it.
The first view we should update has to do with the word “waste” itself. There is value to be found in the so-called waste stream – not in all circumstances, but enough to require a flexible, holistic approach to maximize the stream’s value.
Integrated waste management (IWM) is a new take on dealing with unwanted waste. The notion is that we need to combine waste streams, waste collection, diversion and disposal methods so that we can achieve environmental benefit, economic value and community acceptance.
For example, the majority of a typical waste stream contains glass, metals and carbon-based organics (wood and paper, petroleum-based materials like plastics, plus food and yard waste).
Blue-box programs separate out some glass, metal and paper products from the waste stream. Composting might shrink the amount of yard and food waste. Currently, even after such diversion, more than 50 per cent of residential waste and 75 per cent of commercial waste ends up in waste disposal.
And while we all must continue reducing the quantity of materials that enter the stream in the first place and divert more (through reduction, reuse and recycling), nevertheless 30 million tonnes is a lot of material. What should we do with it?
Recovery strategies are becoming an important part of a menu of strategies for minimizing waste, whether it is achieved through composting organic waste into fertilizer, or burning waste materials or capturing gas from landfills to produce heat and electricity, also called waste derived energy.
A flexible approach to managing our waste disposal might see the recovery of energy from all carbon-based materials that are unsuitable for recycling.
In situations where burning for energy recovery is not the best approach, the methane captured from landfills can be converted into electricity or alternative gas and used as a new energy source.
In both these cases, burning for energy and converting landfill gas can provide new energy sources that offset carbon dioxide emissions resulting from traditional fossil-fuel energy sources such as coal and gas.
Given the level of public interest in CO2 emissions reduction as a means of guarding ourselves against the effects of a warming planet, the benefits of this approach are clear.

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