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 sorted out end up being recycled, the garbage usually ends up sitting 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 the time increases, the amount of land available will decrease, and 2/3 of the Earth is covered by water anyway. With global warming, more land may become submersed. The ocean isn’t immune to garbage either, as 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 study 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 states that Canada should learn from other countries such as Japan, the U.K., Sweden, Finland, and Denmark in order to improve their municipal waste management.
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 recycled. 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 website, 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 pertaining to levels of toxic emissions such as those of nitrogen oxides, sulphur dioxide, heavy metals, and dioxins. The waste to energy plants utilize furnaces which are fed garbage. The garbage is burnt, producing heat which boils water and generates steam. The steam powers generator turbines that can then produce electricity and heating. The electricity is distributed across the country. And just like that, in Sweden, 810,000 households 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 also significantly work on limiting the amounts of released pollutants. Aqueous ammonia can be used to control for 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 generate a staggering 20% of the nation’s total methane production. According to Environment Canada, 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 also concern 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 has only 7 waste to energy plants. They 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 Burnaby, BC, for instance, has been successfully operating since 1988. It produces a sufficient amount of electricity to power 16,000 households, earning Metro Vancouver about $6 million from the sale of electricity. About 8000 tonnes of metals 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 in order to divert the nation’s abhorrent trend of landfilling.
New waste to energy technologies are emerging which are even more exciting alternatives to landfills because these don’t require direct combustion, thus preventing fly ash and reducing the amount of bottom ash. 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 byproduct, 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 byproduct to dump into the landfill.
When I think of landfills, I am often reminded of the scene in Idiocracy where the garbage in their landfill is piled up so ridiculously high that it collapses very dramatically. The image serves not only as a direct parable, but as a metaphor too. As the human population increases, so will the amount of garbage produced. 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.