(116b) Early Career Award Winner Presentation: "Enabling Solvent Recovery and Reuse via Systems Engineering and Synergistic Industry-Academia Collaborations"

With the rapid expansion of the chemical market over the next decade, the concerns for environmental sustainability have increased due to the excessive disposal of chemical solvents. Solvents are typically used as extraction, cleaning, and purification agents and account for up to 90% of the process by mass [1]. To date, there is no proper mitigation plan to handle the inevitable rise in waste volume. These solvent wastes are typically incinerated or released after a single use. However, incineration and direct release are not green methods because of their potentially detrimental effects on the environment [2].

Thus, a systematic framework that employs Process Systems Engineering (PSE) principles, as well as data and timely inputs from Industrial Partners, has been developed to handle wastes from solvent-consuming industries. This Solvent Recovery framework considers multiple alternative recovery and purification technologies simultaneously through a superstructure-based optimization approach [3], [4]. The technologies are represented as mathematical models, which include material and energy balances, utility requirements, design, and operational constraints, as well as sustainability metrics of SPI (Sustainable Process Index) [5] and Emergy [6]. The recovery of solvents from multi-component waste streams is modeled as MINLP (Mixed-Integer NonLinear Programming) problem [7] and the competing objectives of minimizing costs and maximizing process sustainability are handled via the goal programming [8] approach. The results from our work suggest that selecting solvent recovery options require lower costs in comparison to typical incineration and reduce the emission of harmful substances into the environment. Furthermore, a user-friendly software tool that can assess solvent-containing industrial waste streams and predict the best solvent recovery pathways is also developed. This tool could be highly beneficial to pharmaceutical and chemical industries and can lead to better recycling and reuse practices.

In addition to this, a brief overview of the other ongoing projects in our Sustainable Design & Systems Medicine Lab [9] including wastewater treatment, asset management, petroleum pipeline operations, and plastics recycling will be presented. The benefits of synergistic collaborations with industries and government agencies are highlighted in all our projects.

References:

[1] R. A. Sheldon, “The E factor 25 years on: the rise of green chemistry and sustainability,” Green Chem., vol. 19, no. 1, pp. 18–43, Jan. 2017, doi: 10.1039/C6GC02157C.

[2] C. S. Slater, M. J. Savelski, G. Hounsell, F. Urbanski, J. Geiger, and D. Knoechel, “Green Engineering Analysis of a Multi-use Solvent Recovery System for Small Volume Waste Steams in the Pharmaceutical Industry,” presented at the 2010 Meeting of the American Institute of Chemical Engineers, Salt Lake City, UT, 2010.

[3] J. D. Chea, A. L. Lehr, J. P. Stengel, M. J. Savelski, C. S. Slater, and K. M. Yenkie, “Evaluation of Solvent Recovery Options for Economic Feasibility through a Superstructure-Based Optimization Framework,” Ind. Eng. Chem. Res., vol. 59, no. 13, pp. 5931–5944, Apr. 2020, doi: 10.1021/acs.iecr.9b06725.

[4] E. A. Aboagye, J. D. Chea, and K. M. Yenkie, “Systems level roadmap for solvent recovery and reuse in industries,” iScience, vol. 24, no. 10, p. 103114, Oct. 2021, doi: 10.1016/j.isci.2021.103114.

[5] M. Narodoslawsky, “Chapter 3 - Sustainable process index,” in Assessing and Measuring Environmental Impact and Sustainability, J. J. Klemeš, Ed. Oxford: Butterworth-Heinemann, 2015, pp. 73–86. doi: 10.1016/B978-0-12-799968-5.00003-8.

[6] F. Berrios, D. E. Campbell, and M. Ortiz, “Emergy-based indicators for evaluating ecosystem health: A case study of three benthic ecosystem networks influenced by coastal upwelling in northern Chile (SE Pacific coast),” Ecol Indic, vol. 95, pp. 379–393, Dec. 2018, doi: 10.1016/j.ecolind.2018.07.055.

[7] K. M. Yenkie, W. Wu, and C. T. Maravelias, “Synthesis and analysis of separation networks for the recovery of intracellular chemicals generated from microbial-based conversions,” Biotechnology for Biofuels, vol. 10, p. 119, May 2017, doi: 10.1186/s13068-017-0804-2.

[8] U. Diwekar, Introduction to applied optimization, 2. ed. New York: Springer, 2008.

[9] “Yenkie Research Group,” Yenkie Research Group. https://yenkiekm.com/ (accessed Jul. 15, 2022).