Minimum and Complete Fluidization Velocity for Sand-Palm Shell Mixtures, Part I: Fluidization Behavior and Characteristic Velocities
MetadataShow full item record
Problem statement: Palm shell on its original state cannot be fluidized solely. However, mixing palm shell with a second fluidizable material can facilitate proper fluidization. Approach: The minimum and complete fluidization velocity (Umf and Ucf) for sand/palm shell binary mixtures had been studied in a partitioned reactor known as Compartmented Fluidized Bed Gasifier (CFBG). The pilot scale reactor ID is 66 cm with 60:40 cross sectional area ratio for combustor and gasifier respectively. The bed materials constitute of sand and palm shell up to 15 weight percent (wt%). The particle size and density ratio for palm shell and sand are about 5¸53 and 0.55 respectively.Results: Despite of the unique reactor feature, the mixture bed pressure drop profiles were closely resemble to those observed in the laboratory scale cylindrical column. It was found that partial fluidization occurred for the smallest sand size with any palm shell size and weight percent in the gasifier. Poor fluidization was also found with the same sand in the combustor but limited to the largest palm shell and higher weight percent. The Umf and Ucf values increase with the increase of palm shell size and weight percent in both compartments and are in tandem with the increase of effective particle diameter. However, although increase in the sand size also increased the effective particle diameter, the characteristic velocities show both increasing and decreasing trends. These findings proved that the characteristic velocities of the sand-palm shell binary mixtures not only depend on the effective bed properties, but also influenced by the mixing/segregating condition. In addition, bed geometry is an equally important factor for the present system.Conclusion/Recommendation: Despite of the large difference in particle size and density, palm shell in sand can be fluidized well, making it a suitable biomass feedstock for gasification in CFBG pilot plant.
Showing items related by title, author, creator and subject.
Experimental study of a compartmented fluidized bed gasifier for fuel gas production from oil palm shell biomassChok, Vui Soon (2011)Both experimental study of pilot plant scale cold flow model and pilot plant performance testing were carried out in this research with particular reference to palm shell as a biomass feedstock. The reactor was based on ...
Minimum and Complete Fluidization Velocity for Sand-Palm Shell Mixtures, Part II: Characteristic Velocity Profiles, Critical Loading and Binary CorrelationsChok, Vui; Gorin, Alexander; Chua, Han (2010)Problem statement: In Part I of this research, the main features of the fluidization behaviorand characteristic velocities had been reported. Approach: In the present research, the mixturescharacteristic velocity profiles ...
Numerical and experimental study of hydrodynamics in a compartmented fluidized bed oil palm shell biomass gasifierWee, Siaw Khur (2011)Numerical and experimental studies of hydrodynamic parameters of fluidized beds formed by either a single component system or a binary mixture in a pilot plant scale model of a Compartmented Fluidized Bed Gasifier (CFBG) ...