ISSN:0737-3937    

DOI:10.1080/07373939308916837

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

This paper presents a study on the kinetics of dehydration of carrot parallelepipeds which may be useful for a new method which consists in applying a freezing pretreatment. followed by a vacuum dehydration after sample defreezing.allowing instant products to be produced in terms of rehydration ( about 2 minutes rehydration). in this paperare examined effects of effects of pressure (2.6 to 75 kPa). heating conditions (single and double face heating), temperature (50 to 100°c) and sample thickness (3 to 20 mm thick) on dehydration rate.

ISSN:0737-3937    

DOI:10.1080/07373939308916838

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The freeze-drying of a certain pharmaceutical contained in vials in industrial like conditions has been described by a sublimation model under analogous semispherical configuration. Several operating strategies were proved on the basis of considering three different stages during freeze-drying in relation with the modification of heating and product temperacure evolutions. The model offers interesting perspectives to obtain orientative simulated results in heating strategies analysis in order to reduce drying time.

ISSN:0737-3937    

DOI:10.1080/07373939308916839

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

In this paper an experimental and semi-analytical technique is described that provides a method of estimating a macroscopic drying kinetics curve and internal moisture content profiles is described. Moisture gradients and the time evolution of these gradients are analysed as a function of the air drying parameters (dry-bulb, wet-bulb temperature and the velocity) and the product parameters (thickness and density). The material used as an illustration is a maritime-pine-wood.

ISSN:0737-3937    

DOI:10.1080/07373939308916840

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The macroscopic description of drying kinetics and the estimation of the corresponding moisture profiles are coupled by a simple diffusion model. This model describes correctly the drying of a board in a kiln, using a constant mass-transfer coffeicient associated with the drying stage under consideration. Calculations of both the profiles of moisture gradients and time evolution of these gradients, have been made.

ISSN:0737-3937    

DOI:10.1080/07373939308916841

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The use of neural networks to predict performance of a Yankee dryer is presented. A 3-layer network with 4 inputs and 2 outputs is usd. Training is performed using back-propagation algorithm and data from a Yankee simulation program based on Karlsson and Heikkila's model. The trained network is evaluated using randomly generated test cases as input. The effect of number of training cases and hidden neurons are examined.

ISSN:0737-3937    

DOI:10.1080/07373939308916842

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Water adsorption and desorption isotherms at various temperatures have been generated for a variety of particulate materials (ion exchange resin, silica gel, wheat and cellulose materials). Most of thc data were obraincd with the SPS Equilibrium Moisture Content rig, using a dynamic equilibration method. Equilibration over saturated salt solutions at 2°C (static method) was also used for some of the data. Seven semi-empitical correlations, available in the literature, and one developed by SPS have been used to relate the equilibrium moisture content of the material to the relative humidity and temperature of the air. These equations enable the equilibrium moisture content to be predicted under various conditions of relative humidity and temperature from a small number of tests. For each of the six materials tested at least one of the correlations gave a good fit. However, there was no correlation which predicted the equilibrium moisnrre content well for every one of the six materials.

ISSN:0737-3937    

DOI:10.1080/07373939308916843

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Variation on the rate of drying of brown coal powder as a function of environmental and intrinsic properties has been studied in a gravimetric laboratory-scale drier.

ISSN:0737-3937    

DOI:10.1080/07373939308916844

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Agar-agar is a polysaccharide extracted as a hydrocolloid from red seaweed, whose gels are homogeneous, stable and transparent. The characterization of ternary equilibrium and mass transfer kinetics in the agar-water-air system is essential for designing operations in the extractive process as well as for ascertaining the behaviour of these gels and sols during evaporation. humectation and swelling.

ISSN:0737-3937    

DOI:10.1080/07373939308916845

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

An axially dlstrlbuted dynamlc model of a gas-solldcontlnuous fluldlzed bed dryer 1s developed.The steady state formof the model 1s compared with the exlstlng models. Throughslmulatlon profiles of the molsture content and temperature of thebed are obtalned. The transient analysis of the developed model 1sstudled ulth reference to step changes in the air inlet temperature, superficial air veloclty.partlcle residence tlme.lnitial molsture content of the feed and dryer-wall temperature.The results are useful in developlng preclse control strategies to implement on the fluidized bed dryer.

ISSN:0737-3937    

DOI:10.1080/07373939308916846

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor