Master of Engineering Science
Chemical and Biochemical Engineering
Dr. Cedric Briens and Dr. Dominic Pjontek
The aim of the thesis was to study two important features of the Mechanically Fluidized Reactor (MFR): the good distribution of injected liquid on fluidized particles and the high heat transfer rate from the heated wall to the bed. Multiple industrial processes use liquid injection in fluidized bed reactors. The liquid distribution in the reactor should be efficient to minimize bed defluidization and to maximize the yield and quality of the products.
The study used two MFR units, with internal volumes of 1.0 and 4.42 litre, respectively. Induction heating was used to rapidly heat the bed, which is a unique feature of the system.
To characterize the distribution of injected liquid, an experimental method measured the amount of liquid trapped in agglomerates and the mass of agglomerates. The amount of liquid trapped in agglomerates decreased with increasing impeller rotation speed. The best impeller speed to achieve nearly perfect liquid distribution, with only 1 wt.% of the injected liquid trapped in agglomerates, was 130 rpm.
To study wall to bed heat transfer, temperature measurements for the small MFR were used to estimate the overall heat transfer coefficients. It was observed that the overall heat transfer coefficient increased significantly with increasing particle size and a strong influence of the superficial velocity of the vaporized liquid on the heat transfer coefficients was noted. The wall to bed heat transfer coefficient was typical of the values that can be achieved with traditional bubbling fluidized beds, even at vapour velocities below the minimum fluidization velocity.
Small Mechanically Fluidized Reactor (MFR), induction heating system, impeller rotation speed, liquid trapped, overall heat transfer coefficients
Kankariya, Dhiraj M., "Agglomerate Formation and Heat Transfer study in a Novel Mechanically Fluidized Reactor" (2016). Electronic Thesis and Dissertation Repository. 4146.