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Rethinking Your Garbage

Do you ever wonder what happens to your garbage after you throw it out? While we hope that the recyclable materials we painstakingly sort out ends up being recycled, the garbage usually piles up in the landfill. Although the landfill may be a solution for our “throwaway” society, it isn't quite a permanent one.

Do you ever wonder what happens to your garbage after you throw it out? While we hope that the recyclable materials we painstakingly sort out ends up being recycled, the garbage usually piles up in the landfill. Although the landfill may be a solution for our “throwaway” society, it isn't quite a permanent one. Think about how the increasing population on the planet will directly increase the amount of garbage produced, and how land is a precious commodity. As time increases, the amount of land available will decrease, and 2/3 of the Earth is covered by water. With global warming, more land will become submersed in water. The ocean isn't immune to garbage either. Much of it, especially plastic waste, ends up polluting the precious sea life and the water.

According to the Conference Board of Canada, Canada produced 777 kg per capita of municipal waste in 2008. In a ranking the municipal waste generation of 17 countries, Canada ranked last, meaning that Canada produced the most garbage per person. What's worse is that Canada's municipal waste production has been increasing since 1990. The Conference Board of Canada further that Canada should learn from other countries with better municipal waste management such as Japan, the U.K., Sweden, Finland, and Denmark.

Sweden has found a solution in which less than 1 percent of household garbage (municipal solid waste) ends up in landfills, and 99% of the waste is . This is a drastic improvement, since only 38 percent of Swedish household waste was recycled in 1975. How does Sweden do this? First, the Swedes take their recycling very seriously, and recycling stations are situated, “as a rule”, according to Swedish , no more than 300 metres from any residential area. The garbage that can't be recycled is incinerated for energy at their 32 specialized waste to energy incineration plants. In 2012, for instance, 2,270,000 tonnes of garbage was incinerated for energy. Sweden also imports 700,000 tonnes of waste from other countries, at a profit, and turns this foreign garbage into energy too.

“Waste to energy” is the generation of energy, such as electricity and heat, from household garbage (municipal solid waste). Modern waste to energy incineration plants in OECD countries, including those in Sweden, must meet rigid emission guidelines in regards to levels of toxic emissions such as those of nitrogen oxides, sulphur dioxide, heavy metals, and dioxins. The waste to energy plants comprise of furnaces which are fed garbage. The garbage is burnt, producing heat which boils water and generates steam. The steam serves to power generator turbines that can produce electricity and heating. The electricity is distributed across the country. And just like that, in Sweden, 810,000 are furnished with heating and 250,000 with electricity.

While Swedish citizens overall don't seem to be complaining about waste incineration, some people point out that the toxins leaked into the air can be unhealthy for the environment. Even though emission levels of toxins are controlled for, modern incinerators can still emit small amounts of heavy metals, dioxins, particulates, and acid gas in the fly ash. Lime scrubbers and electrostatic precipitators are put on smokestacks to filter the smoke and prevent acid rain, while fabric filters, reactors, and catalysts significantly work on limiting the amounts of released pollutants. Aqueous ammonia can be used to control the amount of nitrogen oxides, and carbon can help control for the amounts of mercury. Phosphoric acid can be administered to counterbalance the ash.

When it comes to greenhouse gases, methane gas is 21 times more harmful to the environment than carbon dioxide. Landfills in Canada a staggering 20% of the nation's total methane production. According to , about 27 megatonnes of carbon dioxide equivalent are produced each year from Canada's landfills, out of which 20 megatonnes of carbon dioxide equivalent are released into the environment annually. About 7 megatonnes of carbon dioxide equivalent are captured from landfills through a gas collection system, and combusted- this has the equivalent effect of taking 5.5 million cars off the road! Much of the carbon dioxide is not captured from landfills. There is that landfill sites are filling up fast, and new sites are increasingly more difficult to find.

Canada needs to step up its waste to energy game. At present, the nation . These are located in Burnaby, BC; Quebec City, QC; Levis, QC; Iles de la Madelaine, QC; Brampton, Ont; Charlottetown, PEI; and Wainright, Alta. The waste to energy plant in , for instance, has been successfully operating since 1988. It produces sufficient electricity to power 16,000 households, earning Metro Vancouver about $6 million from the sale of electricity. About 8000 tonnes of metals from local waste are recovered each year, which earns the city $500,000 annually from the sale of recycled metal. More waste to energy plants should be built in Canada which can divert the nation's abhorrent trend of landfilling.

New waste to energy technologies are which are even more exciting alternatives to landfills because these don't require direct combustion. Fly ash would no longer be produced, and the amount of toxic bottom ash would be minimalized. Conversion technologies involve the heating of municipal solid waste at superheated temperatures in an oxygen-controlled environment to deter combustion. Solid waste is converted to usable products such as synthesis gas, which is mainly made of hydrogen and carbon monoxide. This “syngas” can be burned in a boiler to generate electricity or be processed into a fuel. In a few years from now, more affordable technology could allow this syngas to be cleaned and purified of contaminants, allowing conversion technologies to become an efficient and cleaner alternative to combustion incineration. Newer technologies do not produce as much bottom ash, a toxic by-product, as incinerated waste does. 40% of bottom ash produced by incinerating garbage is thrown into the landfill, and 60% of it is further processed to salvage metals. Conversion technologies can collect metals right away and leave less by-product to be dumped into the landfill.

When I think of landfills, I am often reminded of the where the garbage in their landfill is piled up so ridiculously high that it dramatically collapses. This image serves as a parable of what can happen. As the human population increases, so will the amount of garbage. Canada is generally known as a progressive country with a high standard of living. As a proud Canadian, I would love to see Canada find a good solution for the management of the population's garbage.


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