There has been a dramatic shift in public opinion towards the acceptance of municipal solid waste treatment using gasification or waste-to-energy technology. Thanks to cross-boarder issues, political ...
February 1, 2007
by John Nicholson & Nick Coulthard
There has been a dramatic shift in public opinion towards the acceptance of municipal solid waste treatment using gasification or waste-to-energy technology. Thanks to cross-boarder issues, political feet-dragging and a chorus of firms promoting their brand new technologies, a growing number of the general public is now convinced that gasifying such waste is the best solution. Before the rush to build new waste-to-energy facilities begins, however, landfills and their benefits need to be re-evaluated. It turns out that modern landfills are safe, easy, cheap, and innovative.
Landfills are not just holes in the ground to be filled with trash. A modern landfill employs a number of technologies to ensure that the waste stays put and any escaping emissions are properly managed. Advanced geomembrane liners are used to isolate the waste from the surrounding groundwater; leachate and surface water run-off is collected and treated; and landfill gas is drawn from the ground and used to generate electricity.
In Ontario, the last time there was a major safety problem with a landfill was back in the 1980s. A dump near Georgian Bay was illegally accepting liquid toxic waste which leached into a local aquifer.
Current regulations in many Canadian jurisdictions ensure that landfills offer “state-of-the-art” environmental protection.
The engineering design, construction and daily operation of a landfill is considerably less than that of any other waste treatment options (i.e., thermal treatment).
When speaking with European waste professionals, they are awestruck by the continued reliance on landfilling in Canada. However, whereas their countries are geographically challenged for space, Canada is the second largest country in the world with vast tracks of land suitable for landfill use.
Landfill sites are not forever. A landfill property can be used again within years of the cessation of operations. Many people have enjoyed skiing on the slopes and golfing on the tops at closed landfill sites.
The cost of various waste management and disposal options are often lost in the debate in Canada. Personalize the debate by asking yourself what waste disposal option you would choose if your local municipality charged by the bag for various options: buy a $1 tag and that garbage goes to landfilling; a $3 tag sends the garbage to a thermal treatment facility, and a $10 tag means your waste is sent to a zero waste R&D facility. Faced with a week after week curb side decision, it would be interesting to see what the majority of householders would choose.
There are many reasons why municipalities with control over their own landfill are in an envious position (and why some municipalities will spend a lot of money securing proven sites). These municipalities have considerably lower total disposal costs. Disposal of waste in a landfill is at least half the cost of any other method in operation or proposed. Large sites will also have access to revenue streams from emission reduction credits and power generation.
There are innovative technologies being researched at modern landfills. For example, in Saskatchewan, a Solar Hydrogen Energy Corporation (SHEC Labs) has developed a technology to convert landfill gas into hydrogen using solar energy.
A demonstration of this technology is already under way at a Regina landfill in conjunction with Clean16 Environmental Technologies. A solar-powered reactor converts the two primary components of landfill gas methane and carbon dioxide gas, into carbon monoxide and hydrogen. This process is called dry solar reforming and when coupled with a water gas shift reaction converts methane into hydrogen.
Work at the Department of Chemical Engineering and Applied Chemistry at the University of Toronto has verified the solar reforming process has the ability to generate more GHG reduction credits than typical landfill gas upgrading technologies.
Contrary to where public opinion is headed, landfills will continue to be a practical and necessary part of the waste disposal process across the Canada and people need to reconsider their benefits. Modern landfills offer a safe disposal method, are inexpensive to construct, and easy to operate. Moreover, there’s plenty of open space available in Canada for engineered landfills/ski hills.
John Nicholson, M.Sc., P.Eng., is a consultant based in Toronto, Ontario. Contact John at email@example.com Nick Coulthard is a Graduate Student, Chemical Engineering, at University of Toronto.