Inquisitive student digs into process of plastic compost

Holding up a handful of soil, Shabazz Jackson explains to the author how the composting process occurs. Jackson works for Greenway Environmental Services, which composts Vassar’s food waste. Courtesy of Yunfei Liang.

The story begins toward the end of last se- mester, the first year after Vassar switched to Bon Appétit as its primary food service man- agement company. As a student who’s eaten for two school years under the management of the former provider, Aramark, I find Bon Appétit’s offerings to be superior. Something that I no- ticed from the new food service providers that wasn’t present with the previous is an apparent increase in compostable materials.

When I first used the compostable plastic cups and silverware that are now available at Express and the Retreat, I just assumed them to be regular plastic cups and threw them into the recycling bin. Weeks later, however, I noticed that these cups actually are engraved with words indicating that they are compostable. This got me curious. I’m used to thinking about plastic as something that will never compost—an eternal material. I’d heard of the Great Pacific garbage patch and how plastic dumped into the ocean has been gathered at a common point, proving that the materials of which humans have disposed in the sea might outlive any one of us. The plastic used at the Retreat and at the Deece during Late Night looked, at least to my eyes, identical to the plastic that will never compost. So what makes them different?

I started digging for information on the Internet. First I went on the website of Eco Products, the company whose name is on the plastic cups and silverware we use at Vassar. I found that they use “corn plastics,” or polylactic acid (PLA), a material made from corn. Then I asked Bon Appétit about the material and how it’s processed. The way our college disposes of these materials is far more connected to our history than Vassar simply employing some nameless subcontractor. Vassar students actually developed the process to sort our food wastes into the categories of trash, compost and recyclables.

I began an investigation through the Bon Appétit management, which referred me to Royal Carting, the company that’s responsible for transporting our wastes to the compost facility. I ended up contacting Josephine Papagni, one of the key members of Greenway Environmental Services who nncomposts our food waste. Papagni invited me to tour the compost facility and conduct an interview at the site.

I admit that I do not have a solid of grasp of material chemistry, nor do I know how food wastes are normally managed or posted. When I read that PLA typically is converted from its plastic state to a compostable state by being mixed with hot water (a process known as hydrolysis), I assumed that I was going to walk into an industrial building filled with metal drums and belts carrying our food waste.

When Sam Kobrin ’19 and I arrived at the scene, all we saw were what I thought were mounds of dirt and soil. There were a few pieces of heavy machinery, including some backhoes, a wood chipper and a mound of chipped wood piling several stories tall. The whole area was enclosed by a densely packed forest. The road from the entrance was also unpaved, giving the whole environment a feeling of close connection to nature. It was a far cry from the industrial, synthetic environment I had imagined.

The site looked like a construction zone for a building before any foundations have been constructed. We eventually noticed a silhouette of a man inside one of the backhoes. The man sported a blue onesie and introduced himself to us as Shabazz Jackson. He compared the company’s composting technology to the human stomach in how it breaks down the food wastes the facility receives using a biochemical method and anaerobic bacteria. Protein and PLA alike are transported by Royal Carting to Greenway, and then, using the shovel scoop, that waste is mixed into the mound of soil. The fluids of the dirt allow for the breaking down of the high protein and PLA. Within six to seven hours, the food decays underneath the top layer of compost, which can be used for agriculture—for example, to fertilize the apple farms in nearby Greenway.

At the end of our conversation, Jackson used his backhoe machine to dig into the mound of compost, showing us the remains of fruits (I remember seeing a piece of a mango) and milk cartons buried in the dirt. The rest of the compost looked like rich, dark soil. He then walked us near the front of the gateway, where we could see a garden that was cultivated with the nutrient-rich soil composted perhaps only hours earlier. Apparently, the food waste to output ratio is something like 75:1, and Jackson claimed the soil to be many times more nutrient rich than soil produced by Greenway’s competitors.

My investigation has prompted my curiosity and urged me to conduct more research on the ins and outs of the subject. I find the process behind plastic recycling to be much more fascinating than I realized.

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