Grant: Discovery Grants Program - Individual

Upflowing gas through particles can eventually suspend them to form a "fluidized bed", a layer of suspended particles where the large inter-facial surface area of the particles are fully exposed to the upflowing gas. This "fluidization" technology has been widely applied in industrial processes, utilizing the large surface area. For example, coal combustion in electricity generation was made very efficient by suspending (fluidizing) fine coal particles in the air stream given the effective contact between air and coal particles. The largest application of fluidized bed is in chemical reactors because the suspended particles have excellent contact with the gas phase, leading to very high reaction efficiency. However, particle agglomeration due to very strong inter-particle forces, arising from the reduced particle size, has prevented the use of fine particles of 5-30 microns in fluidization, which would otherwise provide even larger interfacial contact areas. There exists a huge potential to double or even quadruple the reactor efficiency of fluidized beds if one can "release" the large surface area hidden in the agglomerates of those fine particles. In chemical industry, even a small increase in efficiency will lead to huge economic benefits. Originating from his long term working experience with the powder coating industry where nano particles have been routinely added into fine coating particles of 30-60 microns to ensure their good flowability, the applicant has recently proposed a new theory of C-Plus particles (patent pending): The so-called C-Plus particles consist of primarily cohesive Geldart-C particles (5-30 microns) and selected nano-particles to "modulate" the cohesion, making them not only fluidizable but with better fluidization quality. Preliminary tests have shown that the C-plus particles fluidize very smoothly with up to 200% high bed expansion and up to 200% chemical conversion compared to regular fluidized bed reactors. The short term objective of the proposed project is to fully explore this C-plus particle fluidized bed, with parametric study. The long term objective is to commercialize this technology in the process industry. An additional objective is to expand our current fluidization theory to include new theory on the fluidization of fine particles. This is expected to lead to a major breakthrough in the field of chemical reaction engineering. The applicant has been working on various fluidization technologies and fine particle applications for over 25 years, so his group has the expertise and the necessary instrumentations to complete the proposed research. The great research project and the extensive training experiences of the applicant, plus the excellent facility, will provide the best training environment for HQPs.