(4ep) Process Intensification and Optimization of Energy Systems Towards a Sustainable Future

My research interest lies in the development, intensification and optimization of process systems to meet crucial societal needs, such as fuel, chemicals, water, electricity, and food, in a sustainable manner. I am interested in developing new concepts, methods and algorithms to identify and synthesize process schemes to facilitate the transition from fossil to renewable resources, which provides an unprecedented opportunity for reimagining future chemical plants. My past and present research addresses multiple aspects towards sustainable energy systems, which are described below:

Valorization of Shale Resources. A major paradigm shift of process hierarchy is identified for the valorization of natural gas liquids from shale gas. This paradigm shift fundamentally changes the sequencing of various separation and reaction steps and results in dramatically simplified and intensified process flowsheets [1]. Furthermore, recovery of olefins is increased and energy demand is lowered – all at reduced plant capital cost.

Global Optimization of Membrane Cascades. For widespread use of membrane-based process for high recovery and purity products from gaseous and liquid mixtures on industrial scale, availability of models that allow use of membrane cascades at their optimal operating modes is desirable. This will also enable proper comparison of membrane performance vis a vis other competing sepration technologies. However, such a model for multicomponent fluid separation has been missing from the literature. We have developed an MINLP global optimization algorithm that guarantees the identification of minimum power consumption of multicomponent membrane cascades. The model is currently being further developed to include optimization of total cost including capital. Such a model holds the promise to be useful for the development in implementation of energy efficient separation plants with least carbon footprint.

Classification of Dividing Wall Columns. One method to reduce to the cost and therefore increase implementation of low energy distillation processes is to systematically draw dividing wall column version of the efficient distillation configuration. However, availability of seemingly large number of dividing wall designs have alluded a systematic method. We provide a guideline to classify and compare different types of dividing walls in distillation columns enabling quick implementation of these cost reducing technology [2].

Electrification of Chemical Manufacturing. Historically, heat energy is supplied to chemical plants using by burning fossil resources. However, in future, with the emphasis on greenhouse gas reduction, renewable energy resources will find more usage. Renewable electricity from photovoltaic and wind has now become competitive with the electricity from fossil resources. Therefore, a major challenge for chemical engineering processes is how to use renewable electricity efficiently within a chemical plant and eliminate any carbon dioxide release from chemical plants. The use of renewable resources, especially electricity provides an unprecedented opportunity to reimagine chemical plants. The design of many unit operations including endothermic reactors and separation processes are expected to see fundamental changes. We propose a process framework to convert resources, such as shale gas, biomass, municipal waste, air, water, etc. into crucial chemical building blocks such as CH₃OH, olefins and NH₃, utilizing renewable electricity. The results are exciting and paint a picture of future chemical plants and their interaction with local community.

References:

[1] Chen, Z., Li, Y., Oladipupo, W. P., Rodrigues Gil, E. A., Sawyer, G., Agrawal, R. Paradigm Shift of Process Hierarchy for Valorization of Shale Resources. Manuscript Submitted

[2] Chen, Z., Agrawal, R., Classification and Comparison of Dividing Walls for Distillation Columns. Processes, 8(6), 699.