Wednesday, June 17, 2009

What is recycling at the molecular level?

We owe the quality of our lives to our ability take resources and turn them into products we need.

The products we need are then used or consumed and what we don't want is thrown out.

What we throw out goes to be recycled or land filled. Less than 50 % of what we dispose of is recycled, the rest is dumped in landfill for future generations to worry about.

Most of us acknowledge that landfills are a necessary evil, what we don't question much are the alternatives to landfill.

The way we handle waste today assumes waste is a liability.
What if we were to assume that waste is a valuable distributed energy resource? It in fact contains, on a ton for ton basis, about 50% of the energy of coal.

How would we handle it then?

It would become clear that disposal is the lowest level of use for a resource. Incineration is little better. Granted, we can use the energy we generate to fire kilns or create steam for generators, but in reality this is very low level recovery.

We can improve our ability to recycle and I think this is happening all the time, but much of what goes to land fill is beyond recycling as it is currently done. It is a mixture of a wide range of materials, some of it rotting and odorous, much of it is moist and each component contaminates the other components. So what do we do with this stuff?

We tend to think of recycling at a product level. Paper is recyclable, metal is recyclable, glass is recyclable and so are plastics. But what if we look at this material at the molecular level?

Much of what goes to landfill has high levels of carbon. Items such as organics, paper, plastics fibres, carpeting, wood rubber and even asphalt shingles all contain carbon along with hydrogen and oxygen. These elements are bound together in a variety of complex compounds often containing other elements as well.

But instead of thinking about this material at a product level, what if we viewed it at the molecular level? We'd see that it contains valuable energy and compounds which can be transformed into other valuable resources.

We can take this material, vaporize it so it breaks down to its basic molecules. Once we've done this, we can produce what is known as syngas. Syngas is a combination of carbon monoxide and hydrogen and these two components can be used to make a wide variety of valuable fuels and chemical feed stocks. These can either be used as fuels or used as resources to make other useful products.

This is recycling at the molecular level.

It assumes waste has value and in fact enables us to put a value on municipal solid waste. If one takes into account what can be made and sold from MSW, a rough back of the envelope calculation shows that each ton of garbage may be worth around $300 a ton. This technology exists, is available and will become the norm sometime in the near future. More can be learned about this process at

If that's the case, what we dump in landfill in North America each year may be worth upwards of $70 billion.

Do we want to keep burying it in a hole in the ground or do we want to turn it into something useful, thereby cleaning up the environment, reducing methane escape into the atmosphere and eventually getting rid of landfill altogether?

Monday, June 15, 2009

Just how much energy is there in the waste we send to landfill?
  • Estimates vary but somewhere between 1 and 2 billion tonnes of waste go to landfill each year in North America
  • Landfill is our biggest single source of greenhouse gas. 37% of the methane generated in North America is generated by landfill.
  • Methane is 21 times as powerful as CO2 as a greenhouse gas
  • Each ton of solid waste contains about 50% of the energy contained in a ton of coal
  • Only about 2% of the energy in waste sent to landfill is captured and used
For how long can we allow this travesty to continue?

We have to see waste, not as a liability to be disposed of as expediently as possible but as a domestic distributed source of energy. Once we achieve this, we can put up plants that are capable of transforming this waste into valuable forms of energy, such as electricity, fuels and chemical feedstocks, close to the supply of waste. What ever is needed in a particular market can then determine what each plant should be producing.

As citizens we need to demand that our local governments no longer send waste to landfill. This should be a last resort, not the default that it currently is. Most of them wont act until they have no way of avoiding it.