I have been learning a lot about various composting methods over the last few months, mostly from my volunteer hours at the Urban Farm. I personally use both a bin compost system and vermi-compost system (i.e. worm-composting) on my own little urban homestead, but for major operations I was introduced to the “earth tub“. This is totally not practical for a home because it’s huge and expensive (like $10,000 expensive), but it could be fitting at a restaurant or some commercial enterprise interested in sustainable practices.
The earth tub is used at the farm to help process the food waste they receive from the college dorm cafeteria. Although I don’t remember for sure, I want to say this was donated to the farm. It seems they mostly rely on the bin system for composting, plus worms for entertainment, but they can really never have enough compost going at any one time. It’s funny to me that some of these poor college kids don’t even know how to recycle yet, but they are already unknowingly contributing to our compost when they finish their meal. All that good stuff from the cafeteria goes in to get processed – kitchen scraps as well as food leftovers, like stinky potato salad.
A thick later of “browns” are added first, in this case straw. Then the food waste gets thrown on top of that. And then the fun part begins: power tools.
You flip the switch and the auger inside the tub fires up, turning all the layers together. There are little handles along the rim of the bowl for people to push the lid around, which the auger is connected to. Three people turned the top of the bowl while the auger mixed everything up. The whole process was really quick and I found it immensely entertaining to watch. The finished product, well mixed browns and greens, are left to decompose further in the bin.
This is a really expensive machine and probably something none of us will actually ever buy (And for the record I am not getting paid by them for writing about this). It’s just a cool composter and who else do I know that would be interested in cool composters other than you??