Carbon & Hydrogen-Rich Plastics Have High Energy Potential, Can Be Turned Into Fuels Via Gasification [Study]

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According to a report by the World Economic Forum published in January 2016, by 2050 there could be more plastic than fish in the ocean. Nearly everyone, everywhere, every day comes into contact with plastics.

Apart from having potentially disastrous effects on the environment, 95 percent of plastic packaging material value, or $80–120 billion annually, is lost to the economy, and over 30 percent plastic packaging escapes collection systems, the same report states.

Why is this happening, what can we do about it, and why aren’t we using technology that can effectively recycle, convert to valuable products, and extract the energy from plastic?

Those are some of the questions the Earth Engineering Center (EEC|CCNY) at the Grove School of Engineering of the City College of New York has attempted to answer in a new study titled, “The Effects of Non-recycled Plastic (NRP) on Gasification: A Quantitative Assessment,” published by the American Chemistry Council.

Authored by y Marco J. Castaldi, Professor of chemical engineering Director of Earth System Science and Environmental Engineering and Director of the EEC|CCNY, and Demetra Tsiamis Associate Director of the EEC|CCNY, the study, the authors claim, shows that the plastic we’re disposing is, in fact, a resource we can use.

The effects of increasing the NPR percentage were measured at Enerkem, a Canadian energy company, in collaboration with the city of Edmonton.

According to Castaldi and Tsiamis, adding non-recycled plastic (NPR) to gasification – a chemical recycling technology capable of transforming waste materials into fuels – adds economic value and preserves the environment by reducing greenhouse gas (GHG) emissions and the amount of waste byproduct up to 76 percent.

The scientists wrote the following.

“This study measures the effects of increasing the percentage of non-recycled plastics (NRP) in the feedstock for the Enerkem gasification to methanol process. Gasification transforms materials, including post-recycled municipal solid waste (MSW), into a useable gaseous product called synthesis gas (syngas). The syngas is comprised of hydrogen (H2) and carbon monoxide (CO). Subsequently, it can be combusted to produce electricity and heat or converted into basic chemicals and fuels such as methanol and ethanol.”

The gasification process, Castaldi and Tsiamis found, improved along with the increase of plastics in feedstock. This resulted in up to 80 percent increase in syngas energy content (but with only a 2 percent increase in energy inputs), up to 42 percent more methanol production, a decrease of ash to landfill by up to 76 percent, a 28 percent improvement in thermal efficiency, and a net displacement of 21,000 tons of CO2.

In a press release, supplied to Phys.org, Castaldi said that this study shows that there is “tremendous potential to use technologies like gasification to convert these materials into fuels, chemicals, and other products.”

These findings, the researchers wrote, clearly demonstrate that adding NRP to the gasification process would not only improve its efficiency but also increase the output of valuable products, while at the same time reducing the overall environmental footprint.