Diaper-to-Diesel technology… seriously
My Clean Break column this week is about plans to build a facility in Quebec that will process used diapers into oil, gas and char using a pyrolysis process. Engineering giant AMEC has been contracted to build the plant, which will take in used diapers (infant and adult) from hospitals and seniors homes. It makes sense. Pyrolysis is a great technology, but the key to making it work — and by work I mean make a business out of it — is to assure you have a steady supply of predictable feedstock that’s not too expensive to collect and transport. When I say predictable I mean that the feedstock is the same. That is, no surprises like what you get with the mish-mash of stuff that comes from municipal solid waste. If you know the materials you’re dealing with, it’s easier to control the pyrolysis process and maximize its efficiency. Diapers are ideal for this reason — all you’ve got is plastic, fibre, poop, and pee — and in the case of collection and transportation, there’s already a system in existence that you can piggyback. In fact, the company accepting the diapers will make money, not spend it, by charging a tipping fee to the company that does the diaper pickup and disposal for institutions. It’s a model that could be replicated throughout industry with a wide range of materials — if we thought about it.
The output is synthetic gas, a diesel-like oil and char. The gas can be used for power and heat during the pyrolysis process, the char can be used in a wide range of application (or simply mixed in depleted soils, thereby sequestering the high content of carbon inside), and the oil can be used for heating or electricity production, the latter potentially sold into the grid — yet another stream of revenue. AMEC won’t name the company that’s doing this diaper-to-diesel project, but I hope it proves the model successful so that others can adopt it as well.
Tyler Hamilton is senior energy reporter and columnist for the Toronto Star, Canada's largest daily newspaper. In addition to this Clean Break blog, Tyler writes a weekly column of the same name that discusses trends, happenings and innovators in the cleantech market. This blog is a personal project started in April 2005. It is not an official blog of the newspaper. Tyler can be reached at tyler@cleanbreak.ca
November 5th, 2007 at 11:38 am
For pyrolysis to work, the moisture contenet of the feedstock needs to be below 10%. like woodpulp, it can be dried, but it takes some energy. I imagine the smell with be a problem. The smell of the feedstock, the drying, and the pyrolysis itself. nevertheless, this is a very good idea and one that can be rolled out fairly broadly.