If you live in Marquette County, Michigan, you may have seen that big green trailer out and about collecting organic waste at curbsides around town. It's the most visible step to food waste recycling in our composting process, but there's a lot more happening behind the scenes that you may not know about.
As of September 2024, roughly 8 cubic yards of food waste is hauled to our composting site in Ishpeming, Michigan each week. Food waste is collected from Northern Michigan University, restaurants, office spaces, and residences. All collected organic materials are dumped into a row once they get to our site, and mixed with a 50/50 blend of wood chips provided from the city of Ishpeming.
It's important that each row, or windrows as we call them, have a carbon to nitrogen ratio of about 28 to 1. Food waste contains nitrogen and protein, whereas wood chips contain carbon. This ratio creates the perfect environment for thermophilic bacteria. As bacteria metabolizes food waste, they consume oxygen in the process, which generates large amounts of heat. Each windrow remains between 134 °F to 160 °F for nearly two months. High heat is needed to break down the corn starch-based compostable serviceware and bags. We turn each windrow regularly to give the bacteria necessary oxygen and make sure all materials spend time in the center of the row where they decompose quickest.
The high temperatures present in each windrow increases the evaporation rates within the compost pile, so irrigation is needed during the drier summer months. Like any living thing, moisture is needed for bacteria to survive. If our compost piles get too dry, the microbes will die and the composting process itself stops. Our windrows are irrigated with run-off water collected in our retention pond. Not only does this recycle water, it also allows nutrients that have washed away from our piles during heavy rains to be reintroduced into our finished compost.
After several months, our compost windrows drop to ambient temperatures, and are ready to be screened. In the screening process, wood chips are separated to be reintroduced to fresh compost piles, and any contaminates such as metal and plastic are removed. Screening is the last step to our industrial composting process, and our finished compost is then ready to be used to grow new food at local farms and gardens.
Composting your food waste with Partridge Creek Compost is one of the easiest and most sustainable things we can do on a daily basis to combat climate change. This process keeps your food scraps in a closed-loop system, and eliminates the detrimental environmental benefits of their presence in our local landfill. Join us today by signing up for curbside compost pickups and help us grow our programs well into the future!
Comments