Connecticut no longer has landfills. To be sure, if you drive down I-91 near New Haven or Hartford, it is hard to miss the huge landfills that loom like hills along the highway. But those operations are now closed, and no new landfills have taken their place since.
The closure of the state’s landfills was a gradual process that goes back several decades. Hartford’s ‘Mount Trash’ stopped accepting waste in 2015, while New Haven’s landfill shut down in 2004. Southington’s landfill at Old Turnpike Road closed in 1967. Contaminated by heavy metals and solvents, it was designated a Superfund site in 1984 by the Federal Environmental Protection Agency and took some 34 years to be cleaned up.
Connecticut no longer buries its waste in state. So what happens to it? There are two basic answers. Some of it is burned in trash-to-energy plants. However, most of it is sent abroad to states like Pennsylvania and Ohio for burial in landfills there.
Whether done by truck or train, hauling waste a distance of several hours is expensive. In an effort to reduce the waste stream, the state passed a law in 2011 mandating that any facility that produces large quantities of food waste must recycle it. Currently the minimum threshold is 26 tons per year.
The Role of Circular Services
As happens from time to time, passage of legislation paved the way for the growth of a whole new industry. Connecticut now has several facilities that take in and process food waste. Of these, the one owned by Circular Services at 49 DePaolo Drive in Southington is the largest – in fact, it is the biggest facility of its kind in southern New England. It also has some truly astonishing technological capabilities.
During our visit to the Circular Services campus, Marketing Director Michelle Cusano introduced us to Thor. Thor, named after the Norse god, is a huge machine with god-like powers. Perhaps most remarkable is its ability to separate food from packaging quickly and at scale.
Some of the food waste that is brought to Circular Services’ campus is food scraps from hospital cafeterias and college dining halls. But much more of it takes the form of unusable food that has never been cooked or sold. That food is usually packaged. The challenge then is to remove that food from its containers and sort the food and the packaging into separate streams.
That is where Thor comes in. Essentially, the machine works by thrashing the food containers into little pieces that can then be sorted into organic and inorganic bits. It doesn’t matter whether it’s fed bags of popcorn, bottles of soda, packaged meats, or cans of soup – Thor can handle it all. You can see one of Thor's prototypes in action here.
Once Thor has done its work, there is a pile of packaging, which can be binned and shipped to a facility that does conventional recycling.
As for the food waste, that gets piped to Circular Services’ giant fermentation tanks. There it is joined there by food waste that was hauled in without packaging. Trucks full of dairy and other liquid products dump their contents into a giant opening in an oversized garage called 'The Pit.'
The place where the real food-waste magic happens is in the fermentation tanks. There all the waste food streams – meat, popcorn, pineapples, soda, expired milk – gets mixed together. From that point on, anaerobic bacteria do the rest of the work, breaking down the material into more basic components.
Getting the ferment right is a challenge. Anyone familiar with composting knows that it works best when there is a mix of materials - when ‘browns’ like grass clippings are mixed with ‘greens’ like vegetable trimmings. A similar principal applies to the anaerobic fermentation process. Recently, Circular Services had to process a batch of yogurt that didn’t come out right. The batch was large enough that it required 30 tractor trailers to transport. The fermentation tanks were able to handle the yogurt, but only so much at a time. Biochemists at the plant spend a lot of time monitoring the quality of the mix.
As you might imagine, the food waste slurry stinks – while most of the Circular Services campus is odor-free, the area right next to the tanks is a rather pungent. Most of that stink comes from methane gas. As it happens, methane can be burned and used to generate electricity. And that is one thing Circular Services does – burn the methane to power turbines that generate electricity for the local grid.
Once the fermentation process is complete, the organic residue can be used to make various products. One of these is compost. The company has bags of its compost available for sale near its entrance, and also produces the product for a number of area retailers.
The most amazing thing? The compost, which is made in large part from the residue of the fermentation tanks, is black, clean, and smells a lot like clean earth on a warm day after a rainstorm.
Making Mulch
There is one more part of Circular Services’ business model. When tree companies or builders remove trees, they need to find a place to dump their chips and tree stumps. Circular Services takes in those remains and turns them into mulch. State and local officials were on hand recently for the ribbon-cutting of the new building where this mulch is bagged.
That is production cycle for Circular Services, then: waste food and stumps come into the facility, while electricity, compost, and mulch go out.
