(682c) Simulation-Based Computational Framework for Sustainability Assessment and Life Cycle Inventory Generation

Authors: 
Li, S., West Virginia University
Agbleze, S., West Virginia University
Ruiz-Mercado, G. J., U.S. Environmental Protection Agency
Lima, F. V., West Virginia University
In recent years, environmental consciousness has been growing and has become critical in the decision-making process in the chemical industry. This raised awareness has led to the incorporation of the concept of sustainability and sustainable development into process design and optimization, through pollution prevention and control technologies, releases minimization, sustainable process design, sustainability assessment (e.g., GREENSCOPE - Gauging Reaction Effectiveness for the ENvironmental Sustainability of Chemistries with a Multi-Objective Process Evaluator1) and life cycle assessment (LCA) tools (e.g., SimaPro2, Open-LCA3). However, current methods in existing process design/optimization for sustainability studies are difficult to be customized for different applications4. One of the major obstacles for incorporating LCA and sustainability assessment tools into process design and optimization is the software integration among steps. Such steps are typically performed in separate software packages/interfaces, although they have overlapping data requirements5. For example, process design and optimization rely on conventional commercial tools, such as Aspen and CHEMCAD, while sustainability assessment tools (e.g., SustainPro6 and GREENSCOPE) are typically developed employing Excel or other software that require life cycle inventory (LCI) information consisting of resource and energy consumption as well as environmental releases related to the process of interest.

To bridge this gap, an integrated framework with a process modeling/simulation environment, pollution control units (PCUs), LCI generation, and sustainability assessment is proposed. Specifically, a user-friendly automation interface is built via Microsoft Excel-VBA to enable the communication between CHEMCAD (a widely used commercial process simulation tool for chemical processes) and Excel tools, such as GREENSCOPE, PCUs and LCI generation. The employed Excel tools enable the augmentation of CHEMCAD’s capability on waste treatment technologies and LCI estimation. The proposed framework is generic and can be implemented for other applications, with the intent of facilitating the communication between tools used by the LCA practitioner and process simulation packages used by process engineers.

The developed framework is applied to a case study of an Acetic Acid manufacturing process. The application results show process improvements in terms of sustainability performance represented by the GREENSCOPE indicators and LCI generation after the implementation of the appropriate PCUs for waste stream treatment. The case study thus demonstrates the effectiveness of the proposed framework for integrating CHEMCAD, GREENSCOPE, PCUs, and LCI generation for improving the sustainability performance of chemicals during their manufacturing life cycle stages.

References:

(1) Ruiz-Mercado, G. J.; Gonzalez, M. A.; Smith, R. L. Sustainability indicators for chemical processes: III. biodiesel case study. Ind. Eng. Chem. Res. 2013, 52 (20), 6747–6760.

(2) SimaPro LAC software. https://simapro.com/about/ (accessed Apr 13, 2018).

(3) openLCA. http://www.openlca.org/ (accessed Apr 13, 2018).

(4) Bakshi, B. R. Methods and tools for sustainable process design. Curr. Opin. Chem. Eng. 2014, 6, 69–74.

(5) Li, S.; Feliachi, Y.; Agbleze, S.; Ruiz-Mercado, G. J.; Smith, R. L.; Meyer, D. E.; Gonzalez, M. A.; Lima, F. V. A process systems framework for rapid generation of life cycle inventories for pollution control and sustainability evaluation. Clean Technol. Env. Policy. 2018. DOI: 10.1007/s10098-018-1530-6.

(6) Carvalho, A.; Matos, H. A.; Gani, R. SustainPro - A tool for systematic process analysis, generation and evaluation of sustainable design alternatives. Comput. Chem. Eng. 2013, 50, 8–27.