The American Chemistry Council (ACC; Washington, D.C.; www.americanchemistry.com) released a new study showing that emerging technologies designed to convert waste into fuels or raw materials offer environmental benefits and cost savings over disposal.
The study, “Environmental and Economic Analysis of Emerging Plastics Conversion Technologies,” sponsored by ACC’s Plastics Division and conducted by RTI International, examined two types of advanced conversion technologies: gasification and pyrolysis. Although both technologies are capable of processing a range of wastes, the study looked at gasification technology that accepts all municipal solid waste (MSW), including non-recycled plastics, as well as pyrolysis that handles non-recycled plastics only.
When compared to landfill disposal, RTI found that gasification of MSW saves 6.5 to 13 million Btu per ton and 0.3 to 0.6 ton of carbon equivalent emissions per ton. Similarly, pyrolysis, which converts plastics to oil or gas, saves 1.8 to 3.6 million Btu per ton and 0.15 to 0.25 ton of carbon equivalent per ton over landfill disposal.
In the study, RTI reports having identified 41 advanced conversion technology facilities that are under development or undergoing demonstration in North America that will accept MSW or non-recycled plastics as feedstocks. Due to multiple benefits, including potential to produce a range of energy, fuel, feedstocks and chemicals and waste diversion benefits, these waste conversion technologies are expected to become much more attractive in North America in the next five to ten years.
As the range of conversion technologies continues to develop, it should be noted that each variant differs in its requirements, economics and potential benefits. Direct comparisons of the costs and environmental benefits of gasification and pyrolysis technologies are not recommended due to differences in the energy value of the different feedstocks they use and differences in beneficial offsets.