UCL Centre for Nature Inspired Engineering


CNIE presents at the 2020 Virtual AIChE Annual Meeting

26 November 2020

AIChE conference

The CNIE was well represented at the 2020 Virtual AIChE Annual Meeting (16-20 November 2020) with 7 oral presentations from the NICE Group, encompassing nature-inspired solutions to catalyst design, anti-fouling in membrane separations and dynamically structured fluidised beds.

Professor Marc-Olivier Coppens gave two invited presentations: one in memory of Dr Stuart Daw, who sadly passed away last year, and one to celebrate Professor Christine Hrenya, who is retiring this year.

Stuart Daw from ORNL (Oak Ridge National Laboratories, USA) pioneered work that established gas-solid fluidised beds as deterministic chaotic systems. Characterising their complexity mathematically using chaotic attractor properties would open up completely new avenues for scale-up, studying regime transitions, and controlling their hydrodynamics. Having interacted with Stuart Daw since the start of his academic career at TU Delft in the 1990s (in collaboration with Prof Cor van den Bleek), Marc-Olivier looked back at Stuart’s work and how it has impacted the work at TU Delft and now at the UCL CNIE on using chaos theory to help characterise and control fluidised bed processes. His presentation entitled Embracing and Controlling Chaos in Fluidization – in Honor of Stuart Daw can be viewed here.

Christine Hrenya (University of Colorado Boulder) is the winner of this year’s Shell Thomas Baron Award in Fluid-Particle Systems. In honour of her career-wide achievements, Marc-Olivier presented an overview of recent work in the group on The Role of Friction in Pattern Formation in Pulsed Fluidized Beds. Modelling approaches are combined with experimental observations to understand the different conditions under which regular patterns appear in shallow granular layers and deep bubbling beds. Christine and her group’s meticulous work has revealed fundamental insights in fluidization, encompassing scales from nanoscale roughness to macroscopic reactors, keeping industrial applications in mind. In this spirit, Marc-Olivier’s presentation showed how the study of pulsed fluidized beds can reveal new insights on the effect of friction, and the fundamentals of fluidisation at mesoscopic scales, incorporating microscopic information, and relevant to simulate macroscopic gas-solid systems. His presentation can be viewed here.

Recent CNIE alumni Dr Kaiqao Wu (now postdoc at TU Delft) and Dr Victor Francia (now Assistant Professor at Heriot-Watt University) presented some of our most recent work on pulsed fluidized beds. Kaiqiao talked about Particulate Flow Dynamics in Structured Gas-Solid Fluidized Beds. You can watch his talk here. Drawing inspiration from nature (sandy ripples), he presented our newest insights from CFD and PIV on how an oscillatory perturbation in the gasflow can suppress instabilities and induce a periodic bubble pattern. Our Erasmus+ student and recent MSc Roberta d’Avino (University of Naples) participated in this project. Victor’s presentation on Controlled Mixing in a Dynamically Structured, Pulsed Fluidized Bed was based on work started at the CNIE, with a visiting PhD student from the University of Ghent, (now Dr) Laurien Vandewalle (group of Prof Kevin van Geem and Prof Guy Marin). The circulation and mixing behaviour in dynamically structured, pulsed beds is compared with unstructured pulsed beds and traditionally operated beds, without the use of pulsation. The results can be used to inform surrogate models and enable the design and scale-up of larger devices that, besides homogenisation, present unique advantages, namely scalability and external control.

But it was not all about fluidisation. Dr Yanan Liu and Ms Halan Mohamed presented their work in the Bioinspired Membranes and Membrane Processes session. Membrane technology could improve production of clean, fresh water due to its green, energy-saving and continuous operation features, but fouling is a major bottleneck. Yanan gave an overview of her work on improving anti-fouling and mechanical properties of water treatment membranes via a nature-inspired methodology; more on her talk here: Nature-Inspired Graphene Oxide Membrane with Vertical Pores for Fast Water Treatment. Halan’s presentation on Kidney-Inspired Membranes with Enhanced Anti-Fouling Properties, through Grafting of Stimuli-Responsive Polymer Brushes discussed a method to overcome fouling on membranes used in water purification and bio-separations, which is also discussed in her recent article in RSC Molecular Systems Design & Engineering. The respective effects of hydrophilicity and electrostatic interactions were discussed, based on principles observed in kidneys, the inspiration of her work.

Nidhi Kapil, who works on Supported Gold Clusters with Modulated Environment As Highly Stable Catalysts for Propylene Epoxidation, presented at the Catalyst Synthesis & Design: Metal Alloys session of the CRE Division. Propylene oxide (PO) is used as an intermediate to produce polyurethane foams and polyesters. Using gold nanoparticles offers an environmentally benign route for its production. Nidhi could show that gold immobilised onto a titanosilicalite-1 produces clusters with much improved efficiency, selectivity towards PO and stability compared to currently used catalysts. Watch her presentation here.

The virtual format made for a very different experience. Whilst in-person contacts were missed, the prerecording of talks and iPosters (with additional information) made it possible to have a different style of interaction, with a more permanent record. Talks are still viewable until December online for registered members, until 30 days after the conference.