Fluidized-bed granulators and

Nienow, A. W., Fluidized Bed Granulation and Coating Application to Materials, Agriculture and Biotechnology, Proceedings of the First International Particle Technology, Forum, Denver, CO., USA (1994). 

Jager KF, Bauer KH. Polymer blends from PVP as a means to optimize properties of fluidized bed granulates and tablets. Acta Pharm Technol 1984 30(1) 85-92. 

Nienow AW. Fluidized bed granulation and coating application to materials, agriculture, and biotechnology. Proceedings of the First International Particle Technology Forum, Denver, Co., August 17 19, 1994. 

The primary applications for large-scale jetting fluidized beds are in the area of coal gasification as described by Yang et al. (1995), Kojima et al., (1995), and Tsuji and Uemaki (1994). Smaller scale applications are for fluidized bed coating and granulation to be discussed in Chapter 6. 

The main goal of this chapter is to provide a technical basis or framework for analyzing fluidized bed coating and granulation operations. 

The effect of fluid penetration rate and the extent of penetration on granule size distribution from drum granulation experiments is illustrated in Fig. 20 (since no example for fluidized bed granulation is available). From Fig. 20, it is clear that for fluids with a similar extent of penetration, increasing the penetration rate increases the average granule size for various levels of liquid loading. 

Nienow, A. W., Fluidized Bed Granulation, Enlargement and Composition of Particulate Solids, (N. G. Stanley-Wood, ed.), Butterworth and Co., London (1983)... 

Waldie, B., Growth Mechanism and the Dependence of Granule Size on Drop Size in Fluidized-Bed Granulation, Chem. Eng. Sci., 46 2781-2785 (1991)... 

The heat input into the fluidized bed granulation process is controlled with a steam control valve. The settings for the sensors and controls used in the Glatt unit are listed (Table V). 

Full Scale Giatt Mixing. The fluidized bed granulator is one of the most important granulation methods available today, because it combines the unit operations of mixing, granulating, and drying into... 

Zeolite particles are incorporated into a number of different engineered forms, including smaU spherical parhcles for fluidized bed appHcations and smaU granules for powdered detergents. Larger forms include extruded peUets with various cross-sectional shapes and beads made by bead-forming processes. 

The hydration state of risedronate sodium was monitored continuously in a fluidized bed dryer and correlated to data on the physical stability of tablets made from the monitored material [275]. The final granulation moisture was found to affect the solid-state form, which in turn dictated the drug s physical stability over time. The process of freeze-drying mannitol was monitored continuously with in-line Raman and at-line NIR spectroscopies [276]. The thin polymer solvent coatings, such as poly(vinyl acetate) with toluene, methanol, benzene, and combinations of the solvents, were monitored as they dried to generate concentra-tion/time profiles [277]. 

Fluidized bed granulators, or dryers, often require high temperature sensors which are available from many different OEMs and suppliers standard sensors operate only in the 0-70 °C interval. All accelerometers and AE sensors have small dimensions, which makes mounting easy. Figure 9.3 shows how to fix the sensor and cable properly in order to avoid nomelevant vibrations from occurring and interfering with the measurements. 

Fluidized bed granulation monitoring of a fertilizer product (urea) in a semi-industrial pilot plant (SIPP), illustrating the main features and benefits. 

X. Hu, J.C. Cunningham and D. Winstead, Study growth kinetics in fluidized bed granulation with at-line FBRM, Int. J. Pharm., 347, 54-61 (2008). 

However, for Re < 10 the experimental values of Nu fall sharply with decreasing Reynolds number, well below the theoretical minimum of Nu = 2. This is attributable in part to experimental difficulties, for example fhe problem of measuring particle temperature, and in part to the theoretical interpretation of the data. Botterill (1975) posed the question of what exactly is measured by a bare wire thermocouple inserted in a fluidized bed. Despite the uncertainties in the experimental evidence, Botterill concluded that it probably does indeed measure the particle temperature. This was the assumption of Smith and Nienow (1982) who used bare wire thermocouples to measure bed particle temperatures during fluidized bed granulation. In the region Re < 10, as Kunii and Levenspiel (1991) indicate, the data can be represented by an expression due to Kothari... 

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