Rethinking Your Garbage

garbageDo 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.

Sierra Delarosa





Chronicle of a Crime Foretold

By Rodrigo Palau

coltan miningOn September 13th 2012 the Colombian Police confiscated over 1 million dollars in merchandise from the FARC guerrilla, in a historic operation. What made it a first in history was not the value of the seized goods, or the amount of material found, but rather the nature of what they discovered, as it did not turn out to be any sort of narcotic. Instead the police forces found 17 tonnes of greyish, dull looking rocks. Why would lumps of dust and stone be as or more profitable than illegal drugs, which the FARC have historically used to finance themselves? The answer, quite literally, lies at the tip of my fingers, in the computer I’m using to write this article.

The 17 tonnes of rock turned out to be a mineral known as coltan, rich in the elements niobium (formerly called columbium) and tantalum. These two elements are found in the middle block of the period table, the transition metals. In general, the elements in this block are what we commonly associate with the word “metal”, shiny, strong, and good conductors of heat and electricity. The element tantalum has a large capacitance (the ability to store electric charge) per unit weight, making it excellent for specialized, high technology applications. Just a few decades ago these technologies were quite rare, only advanced military and scientific equipment required such materials. The expansion and development of technology has brought these materials into our daily lives, in computers, smartphones, and similar gadgets, creating a booming demand.

Coltan mining attracted international attention in the middle of the last decade, when it was found that in the Democratic Republic of Congo, one of the world’s largest producers at the time, the environmental impact of the mines was threatening the survival of the mountain gorilla. As international concern grew over this devastation, and the fact that the DRC is in a politically unstable region, companies and governments began to look for other sources. Countries around the globe realized that the stakes were very high, to the extent that when mines were found in Venezuela, President Chávez quickly militarized them.

Across the border in Colombia the government confirmed, in 2009, that deposits had been found in the east of the country; a sparsely populated region of great environmental importance, as the Amazon rainforest begins there, and home to many indigenous peoples. Even though the export of coltan was banned, small-scale illegal mining of the mineral grew rapidly. The FARC guerrilla, who operates in these territories, at first forcibly charged a “toll” to allow smugglers to carry out their activities, but then realized that the distribution and transportation networks used for drugs could also be used to commercialize the mineral and decided to engage directly in the mining business, answering the question of why on earth a drug-trafficking organization would smuggle lumps of rock.

The tale of easy money, absence of strong institutions and illegality is a worryingly common one in Colombian history, though it is not too late for the government to act, especially now that peace talks with the guerrilla are underway. Nonetheless, global picture is of great concern, not only with coltan, but in general that the speed at which science and technology develops has the ability to dramatically transform economies. We often hear that technology has revolutionized society by means of what it can do; rarely do we remember that it can also do so by means of what it is made of.

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