摘要:

In granulation, coating or drying of slurries on inert particles a liquid phase is added to a gas-spouted bed. The effect of liquid injection on spouting velocity, fountain height, bed pressure drop and stability of the spouting regime is examined in a 0.15 m diameter bed with four types of inert particles 2 to 5 mm in size, 1140 to 2880 kg/m3in true density, and 1.3 and 1400 mPa·s in liquid viscosity. Key factors are the liquid content and the presence of cohesive forces due to liquid bonds between particles. In a spoutability chart the maximum spoutable liquid content is related to the ratio of inertial force of a particle to the viscous or cohesive force exerted onto the particle by the liquid film. The spoutability chart serves to define regions of stable spouting.

ISSN:0737-3937    

DOI:10.1080/07373939308916820

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Experiments were carried out in order to analyse the wall-to-bed and fluid-to-particle heat transfer coefficients in spouted Beds. wall-to-bed heat transfer coefficients were determined in cylindrical-conical and conical spouted beds for various gas flow rates, particle sizes and bed heights for spouted beds with and without draft tubes.

ISSN:0737-3937    

DOI:10.1080/07373939308916821

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

This paper presents kinetics of batchwise drying in a spouted bed apparatus with cyclically shifted gas stream, i.e. drying medium flowrate is changed cyclically along inlet cross-section of a bed during operation time.

ISSN:0737-3937    

DOI:10.1080/07373939308916822

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Geometrically similar spouted beds with draft plates were used to obtain the drying characteristics of freshly harvested shelled corn with 0.28 to 0.31 kg/kg initial moisture content at different air inlet temperatures and bed heights. Thermal equilibrium between air and grains was achieved at minimum spouting conditions. The drying kinetics of shelled corn in a drafted two-dimensional spouted bed was found to be of the "thin layer" type. Expressions for the model parameters in Page's equation accounting for the bed geometry, grain moisture content, and drying conditions were developed.

ISSN:0737-3937    

DOI:10.1080/07373939308916823

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

A study of the operation of a draught tube spouted bed in conjunction with dielectric heat addition was carried out. The addition of radio frequency allowed a greater amount of energy to be input into the particulate material in any given time, increasing the drying rate: however, the drying pattern was unaffected by the ratio of radio frequency to convective heat addition. The rate of moisture loss was proportional only to the total energy input. The synergy which often occurs with low levels of radio frequency addition does not occur with rf enhanced spouted beds.

ISSN:0737-3937    

DOI:10.1080/07373939308916824

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

An experimental study was conducted to apply the jet spouted bed (JSB) dryer with inert bodies for drying of fodder antibiotic; (zinc-salt bacitracin and tylosin) and baker's yeast which are extracted from fermentation broth. After establishing the drving properties of these products (e.g. sorption isotherm, water activity and thermostability), the influence of basic drying parameters (temperature of drying agent, bed loading, gas flow rate) on drying characteristics and quality of the products was determined. The results proved that a JSB dryer may be successfully applied to fodder antibiotics; especially to Zn-bacitracin; however, for a highly labile live organism like baker's yeast, this method cannot be used. The optimal parameters for drying of Zn-bacitracin have been presented.

ISSN:0737-3937    

DOI:10.1080/07373939308916825

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

A 0.15 m diameter half cylindrical spouted bed was used to dry a ferric hydroxide - zinc hydroxide sludge with a moisture content of 83.4 % wet basis. Heat for drying was provided by an electrical air preheater. The sludge was fed through an air cooled feeder into the spout and dried product was removed by elutriation; it was captured by a cyclone and baghouse. The mechanisms of drying and the performance of the drier were studied as a function of the operating variables. A glass front panel was used for visual observation of the system to elucidate the drying mechanisms, a stainless steel panel was used at other times.

ISSN:0737-3937    

DOI:10.1080/07373939308916826

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Two alternate mechanisms of cereal grain drying are posed, based on a comparison of predictions from their respective mathematical models with the experimental data of Zuritz and Singh (1982) on spouted bed batch drying of rough rice.

ISSN:0737-3937    

DOI:10.1080/07373939308916827

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

ISSN:0737-3937    

DOI:10.1080/07373939308916828

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

ISSN:0737-3937    

DOI:10.1080/07373939308916829

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor