Sustainability Assessment and Simulation of Phthalic Anhydride Production from o-Xylene

The United States Environmental Protection Agency, EPA, has been increasingly regulating chemical processes for their emissions of greenhouse gases, energy consumptions, as well as other factors. The EPA has also been developing assessment tools to determine the sustainability of chemical processes. One of these assessment tools is the GREENSCOPE software (Microsoft Excel® Version), which assesses economics, environmental, efficiency, and energy aspects of processes. This tool has approximately 140 indicators in all aspects, in which the results of the indicators are shown on radar plots. These plots show the percentage values of the indicators in a radar fashion, i.e., the center of the plot represents a value of 0% sustainability and the outside edge of the plot corresponds to a value of 100% sustainability.

For this presentation, a sustainability analysis is performed on the chemical process of the production of Phthalic Anhydride using o-Xylene, which is simulated using CHEMCAD. The process values needed for the GREENSCOPE assessment are exported from this CHEMCAD simulation using data mapping. Eight indicators are chosen based on their relevance to the process - two indicators from each category. The indicators chosen for this process are mass loss index, renewability material index, capital cost, total energy cost, health hazard, environmental quotient, specific energy index, and resource-energy efficiency. The obtained results show that the percentage values of these indicators for the process nominal case are 70.86%, 96.40%, 76.25%, 100.00%, 99.88%, 97.26%, 0.00%, and 100.00% respectively. The results for this study will be discussed in this presentation.