Numerical Study and Analysis of Chaotic Advection During Free Radical Polymerization Reactions in Coiled Flow Inverter Microreactor | Department of Chemical Engineering

Numerical Study and Analysis of Chaotic Advection During Free Radical Polymerization Reactions in Coiled Flow Inverter Microreactor

Project No. YSS/2015/002088

Chaotic advection is one such phenomena which improves mixing without any consumption of energy. Whereas Coiled Flow Inverter Microreactor (CFIM) is one such simple chaotic tubular reactor design which incorporates the chaotic advection as well as diffusion to promote mixing. Such phenomena and reactor design are highly desirable in today’s world when energy prices and raw material cost are rising and concern for the environment is increasing day by day. Green Technology alongwith Process Intensification is the need of the hour.

Chaotic advection can be utilized efficiently for carrying out free radical polymerization (FRP) reaction in CFIM. CFIM is already shown to be promising reactor for carrying out FRP through experimental as well as CFD simulations. It was found that CFIM needed to be optimized for FRP by maximizing the extent of chaotic advection which is not the case in present geometric configuration and operating conditions. For this, numerical study of chaotic advection during FRP in CFIM can be of great help as experimentally, it would be quite costly and time consuming affair.

This requires a well-developed model for simulating FRP through CFD for the desired experimental/ operating conditions. This requires the incorporation of gel/glass and cage effect at higher conversion. For this, AK model will be used which is most theoretical and accurate model available based on free volume theory for diffusion in polymer solution. Then, a geometric optimization of CFIM, e.g. tube inner diameter, number of bends, curvature ratio etc. through CFD is to be obtained for a given and different operating conditions for FRP. All this will require large number of simulations as well as large computational power. This study may yield some new conditions and/or parameters characterizing chaotic advection with geometric configuration, flow and fluid conditions and reaction kinetics. This experience can then be extended to other monomer-polymer systems as well as other similar chaotic tubular geometric configurations.

Based on the outcome of this project, a CFIM can be found which can have maximum output with desired specifications while still retaining the benefits of microreactor. A pilot plant with CFIM can be setup based on such results. A dynamic simulator can be developed based on the FRP model developed in this project. This can help in evaluating pilot plant performance, predicting its outcomes under various operating conditions, thus help in choosing the best ones. It can also act as a training simulator. A successful operation of pilot plant can help in scaling out the CFIM using the principles of process intensification. Its experience can be used to commercialize it. Besides this, the gained knowledge could be used to design other better chaotic tubular configurations. This can further improve the process intensification desired.

Keywords: Chaotic Advection, Free Radical Polymerization, Coiled Flow Inverter Microreactor, Process Intensification, Optimization, CFD.

    This Project is going on under Dr. Dhiraj Kumar Garg.

    The objectives of this project are as follows:

    1. To make the modelling of FRP in CFD as complete as possible to include all the relevant effects (gel, glass, and cage effect at higher conversion, variation of diffusion of individual chemical species in polymer solution alongwith variable fluid thermo-physical properties with conversion).
    2. To validate the CFD simulation results obtained through modelling obtained above against the experimental data under similar operating conditions.
    3. Visualization of chaotic advection through existing mathematical tools.
    4. To perform the geometrical and operational optimization of CFIM with the objective of maximizing the extent of chaotic advection.
    5. To figure out new correlations, conditions, parameters, if possible, characterizing the role played by various geometric, kinetic parameters, and fluid and flow conditions in affecting chaotic advection and its extent.
    6. To extend this study to other monomer/polymer systems.

    Expected Output and outcome of the experiment

    1. A comprehensive and reliable CFD model of FRP. It could be used for simulating almost all conditions of operations. This can be used for optimizing reactor operating conditions in existing industrial reactors and also helps in improving the reactor design for FRP.
    2. A pilot plant can be setup based on optimized CFIM specifications and can further validate the results. Its operation can give us the idea of its commercial viability. Patent can be obtained if possible.
    3. The knowledge gained through the optimization of CFIM for maximizing chaotic advection can be applied to search for other better chaotic tubular configurations.

    Faculty

    Assistant Professor