An integrated environmental impact assessment of corn-based polyols compared with petroleum-based polyols production

Various aspects of bio-ethanol technology have been studied for decades; however the previous literatures do not have a detailed assessment of a whole corn-based polyols system and its integrated impact on the environment. The evaluation system used to analyze the impact of adopting corn-based polyols from an environmental point of view was the system dynamics innovatively. Consequential models were applied to evaluate the environmental impact in four polyols production stages: raw material planting, corn-based polyols production, corn-based polyols products utilization and disposal process. N2O emission from nitrogen fertilizers was important contributor of greenhouse gases produced during agricultural activities. Growing corn was capable of absorbing a lot of CO2 which showed carbon sink. Pollutants discharged during the conversion of corn into polyols were highly dependent on processing technology alternatives. There also existed some worse impacts such as discharged N2O, CO, SO2 and HCl in waste disposal process. Findings from the systemic simulation might be utilized in identifying environmental pollution bottlenecks within the process. The results demonstrated that multiple scientific and technological improvements in polyols production could reduce 1/3 of the production cost per ton in comparison to petrochemical polyols. Through optimal parameter selection, the corn consumption per ton of polyols production could be controlled from 1.68 to 1.42 tons. These findings could provide impetus for further technological advancement of corn-based polyols by reducing the overall environmental impacts of the bio-polyols process.