By Jeremy Biello and Max McNeil
As research becomes a bigger focus for Cleveland State University, junior Nick Plentovich, a chemical engineering major, recently shared an in-depth look at his research on landfill alternatives.
The research focused on the gasification of PET, the act of turning solid plastic into gases. Inside the lab, ground-up plastics are mixed in a cylinder with water and a catalyst, in this case, Ruthenium.
These materials are placed into a small pressurized reactor and heated to 315 degrees Celsius while being stirred. After the heat and pressure are applied to the mixture for 24 hours, a combination of gasses are released as a by-product of the reaction.
In a lab setting, a small sample of the gases are extracted for analysis of the contents. This analysis provides data that determines exactly what gases are contained within the sample.
The idea is to turn the plastic into CO (Carbon Monoxide) and CO2 (Carbon Dioxide) and then turn those gases into methane. Critics of this technique may focus on the remaining CO or CO2 that does not become methane.
“Typically, in chemistry, we study, ‘we convert all of it,’ but it’s not a perfect world, and that kind of ideology is based on just pure theory and in reality that will never happen,” Plentovich would remind them.
While these compounds are harmful either to the environment or humans, they are recycled at an efficient rate that leaves negligible amounts remaining.
Methane is also known to have negative effects on the planet. A common argument against the meat industry is the damage methane does to the environment. The way around that issue in this process is similar to how the CO and CO2 are converted into methane — the methane can be converted into energy.
“Methane can be used in a combustion engine to create electricity,” Plentovich explained.
With this in mind, facilities that run this operation can utilize the methane to reduce some of the energy required to power the plant.
In the future, these operations could help alleviate the mass amounts of plastics that are already contained within the nation’s landfills.
“Things like plastic water bottles, their life span is really, really long,” Plentovich said. “Even if you just sit them somewhere, they last forever, but if you put it in this reactor, it can be gone overnight.”
With reduction of plastic waste being one of the focal points of the environmental movement, this process has an indispensable role in the future of the planet.
Not only will the future of these facilities aid in reducing plastics, they would also be incredibly safe. That can be hard to believe with the reactor being so highly heated and pressurized.
“Obviously, high temperature is a concern,” Plentovich conceded. “High pressure is a concern because if for some reason your reaction vessel is to fail, it will either depressurize, which is the most likely scenario, but for some reason if it were to seal and keep pressurizing, it will fail and just explode, which is really not ideal. That’s worst case-scenario.”
A simple failsafe can be installed in order for depressurization to occur in case of disaster. Also, the components involved in the operation are benign when compared to materials in other plants, such as a nuclear energy facility.
With this higher level of safety comes an increase in the amount of areas where a plant could be implemented. Densely populated residential areas would have nothing to fear if one was located nearby.
Plentovich could not give a solid prediction to how efficiently these plants would run on a grand scale, but was sure that the concept of trash-to-gas would be useful in space travel. NASA tends to agree with him. Some funding for this project was provided by NASA, as well as new equipment. With the exception of a university in Japan, NASA and Cleveland State are the only groups studying this process.
State universities and space administrations can do research on this topic for years, but even if they implement this process into their daily duties, not much effect will be had on the environment.
Plentovich believes the success in these facilities would not be invisible to waste management institutions. They “would be a prime adopter of this because they’re starting to run out of landfills,” he said.
With little space left for more landfills it is likely for them to invest in these smaller facilities that are capable of eradicating the waste they process entirely.