Trends in sustainable process design—from molecular to global scales

The quest for sustainability is changing how chemical engineers conceptualise new processes. The task also becomes more complicated by economic and social uncertainties, local diversity of renewable resources and globalisation. These realities are changing the nature of process design problems and recent advancements have been able to incorporate the multidimensionality and multiscale boundaries by exploiting the power of mathematical methods, decision support frameworks and insight based methods. In doing so, two main trends for methods development can be distinguished, the ones considering expanded boundaries for design from the lowest molecular level to the process level, and the ones from process to the higher levels of value chains, ecosystems and the planet. However, a truly integrated framework that captures the full range of scales and interactions from molecular to planetary levels is yet to be developed to be able to find superior designs that perhaps we had never thought of before.