Energy conversion fluidized beds

A theory has been developed which translates observed coke-conversion selectivity, or dynamic activity, from widely-used MAT or fixed fluidized bed laboratory catalyst characterization tests to steady state risers. The analysis accounts for nonsteady state reactor operation and poor gas-phase hydrodynamics typical of small fluid bed reactors as well as the nonisothermal nature of the MAT test. Variations in catalyst type (e.g. REY versus USY) are accounted for by postulating different coke deactivation rates, activation energies and heats of reaction. For accurate translation, these parameters must be determined from independent experiments. 

For fluidized beds, one essential operating parameter is that of gas throughput this is necessary for fluidization of the bed material, and depends on the diameter and density of the particles and on the density and viscosity of the gas. These studies highlight the fact that sulfur dioxide conversion is decreased at increased gas flow rate, and thus with higher energy input. As a result, a more rapid drying of the liquid contained in the bed occurs with a coupled decrease in the mass transfer surface. 

Tabi, R. and Mesko, J. E., "First and Second Law Analysis of an Advanced Steam Cycle with Fluidized-Bed Heat Input," in Proceedings of the 14th Intersociety Energy Conversion Engineering Conference, Vol. 2, pp. 1767-1773, ACS, Washington, D.C. (1979). 

G. Manos, A. Garforth, and J. Dwyer, Catalytic degradation of high-density polyethylene over different zeolitic structures, Ind. Eng. Chem. Res., 39, 1198 (2000). X. Ji, J. L. Qian, and J. Q. Wang, Study on the conversion of polypropylene waste to oil in a fluidized bed reactor. Energy Sources, 23, 157, (2001). 

Patil DJ, Smit J, van Sint Annaland M, Kuipers JAM (2006) Wall-to-bed heat transfer in gas-solid bubbling fluidized beds. AIChE J 52 58-74 108. Peirano E (1996) The Eulerian/Eulerian Formulation Applied to Gas-Particle Flows. Report A96-218, ISSN 0281-0034, Department of Energy Conversion, Chalmers Univesity of Technology, Sweden... 

The technology of conversion of Ukrainian high-ash coals in pressurized circulating fluidized bed was developed in Coal Energy... 

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