(194b) Introducing Sustainability Criteria in the Chemical Engineering Design Projects: A Case Study of Green Ammonia

Authors: 
Guillén-Gosálbez, G., Imperial College London
Galán-Martín, Á., ETH Zürich
Negri, V., ETH Zürich
Sustainability has become a major concern for chemical companies seeking to remain competitive in the market place. Our graduates in chemical engineering must, therefore, be well equipped to address the challenge of designing processes to meet the growing demand for chemicals and fuels more sustainably.

In this talk, we would like to share with the audience our current efforts at the Institute for Chemical and Bioengineering (ICB) at ETH for including sustainability criteria in the design projects taught in the Chemical Engineering studies. Our approach is based on three main interconnected elements: (i) the choice of a highly relevant project in the area of sustainable fuels and chemicals; (ii) the use of computer-aided tools to carry out the necessary calculations to quantify the economic and environmental performance of a process; and (iii) the application of life cycle assessment (LCA) principles to measure the environmental footprint of a chemical considering its entire life cycle.

Organized in groups, the students work intensively on a given topic during one week to develop a preliminary process flowsheet and carry out mass and energy balances, as well as economic and environmental calculations. Daily meetings ensure that they progress smoothly towards the final goal of producing a sensible design meeting the goal specified. Sustainability criteria are embedded in the problem statement right from the very beginning, rather than considered “a posteriori” in the later stages of the process design.

Using green ammonia as a case study, we will explain how we define the project and motivate the students to find more sustainable production pathways for an existing chemical. The goal here is to replace fossil ammonia by green ammonia, where the later uses electrolytic hydrogen produced from renewable energy rather than fossil hydrogen generated from natural gas.

Overall, the focus on sustainability improves the students’ experience by boosting their motivation while exposing them to the latest trends in sustainability.