Renewapoo

As they say, one man's trash is another man's treasure.  My good college friend, Marc, and I have a recent obsession with biochar, a stable form of carbon, converted from biological sources.  In our case, we are interested in the conversion of <ahem> "poo", specifically the sludge that exits the municipal waste water treatment plant.  The thinking is that the process of making charcoal from common waste streams might be a way to a) generate energy, b) produce a beneficial soil amendment, and c) provide a way to sequester carbon in the soil.  Right now, the going rate for biochar is between $100 and $1000 per ton.  In the fledgling carbon markets, a metric ton of CO2 will cost you between $10 and $30.

Earlier in the summer, we took a tour of the Rochester Water Reclamation plant for a firsthand look at how the city processes its sludge to get a better sense of how viable it might be to process into biochar. After that, I was so excited, I decided to try to make some biochar myself.  Luckily, YouTube is a goldmine of info for do-it-yourselfers, so I basically copied someone's homemade pyrolytic biochar reactor, in this case, a so-called "top-lit updraft" or TLUD, made from paint cans and stove pipe from the hardware store. 

Water reclamation plant

And the first batch of charred wood pellets

For the next burn, I dragged the stove to St. Paul to give it a try with Marc.  Here we are for round 2 on a windy afternoon, trying to keep the smoke stack from blowing over.

Marc, examining the result of our second batch, only partially-charred batch this time.

 Bits and pieces of our growing collection of chemistry equipment, i.e. discarded kitchen implements.

For round 3, I enlisted the help of Sarah's cats, Felix and Oscar, and charred a handful of their... well, you get the idea.  Here is the result, converted to perfectly sterile lumps of charcoal.