Jet-spouted Bed Research Articles

Effects of Process Parameters on Quality Changes of Shrimp During Drying in a Jet‐Spouted Bed Dryer

The objective of the present study was to investigate the effects of various parameters, that is, concentration of salt solution (2%, 3%, 4%[w/v]), boiling time (3, 5, 7 min), drying air temperature (80, 100, 120 degrees C), and size of shrimp, on the kinetics of drying and various quality attributes of shrimp, namely, shrinkage, rehydration ability, texture, colors, and microstructure, during drying in a jet-spouted bed dryer. In addition, the effects of these processing parameters on the sensory attributes of dried shrimp were also investigated. Small shrimp (350 to 360 shrimp/kg) and large shrimp (150 to 160 shrimp/kg) were boiled and then dried until their moisture content was around 25% (d.b.). It was found that the degree of color changes, toughness, and shrinkage of shrimp increased while the rehydration ability decreased with an increase in the concentration of salt solution and boiling time. Size of shrimp and drying temperature significantly affected all quality attributes of dried shrimp. The conditions that gave the highest hedonic scores of sensory evaluation for small dried shrimp are the concentration of salt solution of 2% (w/v), boiling time of 7 min, and drying air temperature of 120 degrees C. On the other hand, the conditions that gave the highest hedonic scores of sensory evaluation for large dried shrimp are the concentration of salt solution of 4% (w/v), boiling time of 7 min, and drying air temperature of 100 degrees C. The quality attributes of dried shrimp measured by instruments correlated well with the sensory attributes, especially the color of dried shrimp.

Bed Voidage in Conical Sawdust Beds in the Transition Regime between Spouting and Jet Spouting

From the results obtained for different geometric factors of the contactor (angle and inlet diameter) and for different operating conditions (particle size, stagnant bed height, and air velocity), the validity of a linear correlation based on the ratio between drag and gravitational forces is proven for the calculation of bed voidage in conical spouted beds when they operate in the transition between the regimes of a spouted bed and a jet-spouted bed. The parameters of this equation are calculated from the correlations previously proposed for the calculation of the bed voidage corresponding to these extreme regimes. The dependency on these parameters of the geometric factors and operating conditions has been determined.

A Two-Dimensional Finite Element Model For Wheat Drying In A Novel Rotating Jet Spouted Bed

ABSTRACT Based on Liquid diffusion model a two-dimensional finite element simulator was developed for the drying of wheat. Simulations were carried out for the drying of a single wheat particle in a novel rotating jet spouted bed. The effects of the choice of the geometric model for the wheat kernel, the temperature and flow rate of the drying air on the moisture removal rate as well as kernel temperature were investigated. Numerical experiments showed that the accuracy of the model geometry chosen has great influence on the computed moisture removal rate partly because of the way the moisture published diffusivily correlations were obtained. Sample results are presented and discussed.

Solid Flow in Jet Spouted Beds

Filming equipment combined with an image treatment program has been used to study the positions of the particles in the jet spouted bed (or dilute spouted bed in conical contactor). The properties determined were the density functions for distribution of particle trajectories and of their maximum heights in the bed and local bed voidages. The spout geometry has been determined for this regime. By extending the experimental study to systems with different values of contactor inlet diameter, stagnant bed height, and relative air velocity with respect to the minimum needed for the jet spouted bed, the effect of these variables on the properties that describe the solid flow has been analyzed.

A Mathematical Model for Constant and Intermittent Batch Drying of Grains in a Novel Rotating Jet Spouted bed

ABSTRACT A diffusion-bared mathdcal model is prswmed for batch drying of corn in a novel rotating jn spouted bcd device under constant as well as intermitted drying conditions. Such a device is suited for drying of large partides (e.g. grains, beam, seed, etc) for which internal heat and mass tranfer rates control the drying kinetics. Based on literature data for moisture diffusivities the model predictions are compared with experimental data for both continous and time-dependend air supply and/or heat input. Effects of dcvant parameter are evaluated and discussed in the light of potential pnrctieal applications.

Continuous Drying of Slurry in a Jet Spouted Bed

ABSTRACT he performance of a laboratory scale jet spouted bed (JSB) for drying rice flour slurry was studied. The bed consisted of ceramic balls (5028 mm diameter) and the rice flour slurry was sprayed onto the moving particle surface near the inlet part. All the experiments were carried out at the jet spouting regime. This regime has high bed void fraction and violent movement and collision of bed particles. As a result, the dried product layer is attrited from particle surface as a fine powder and entrained from the bed by the spouting air. The experimental result were presented to show the effects of static bed height, inlet air flow rate and temperature, and feed concentration and flow rate on the outlet air temperature, thernal efficiency, and mean particle size and moisture content of the product. Asimple mathematical model, which is based on the conservation of mass and energy equations, was developed. Predicted results agreed well with those obtained from the experiment.

95/00317 Coal gasification in a jet-spouted bed

95/00317 Coal gasification in a jet-spouted bed

二段噴流層式石炭ガス化装置の開発

The application of the spouted bed technique to a coal gasifier has been studied in order to operate at the optimum temperature range of the gasification. The gasifier developed is composed of two parts. Jet-spouted bed reaction proceeds at the first stage in the lower part of the gasifier, and conventional spouted bed reaction at the second stage in the upper part of the gasifier. Regime maps of the jet spoutability and conventional spoutability in a column were determined.Taiheiyo coal was gasified with oxygen-steam mixtures in the dry ash mode under atmospheric pressure at temperatures up to 1350K. The effects of the oxygen/coal ratio and coal feed rate on the gasification performance were investigated. As a result, it was found that both the carbon conversion and thermal efficiency were mainly affected by the oxygen/coal ratio. The fractional conversion of carbon was 0.93 and cold gas thermal efficiency was 0.74 at the oxygen/coal ratio of 0.87. The product gases contained about 43% hydrogen and 20-30% carbon monoxide.The gasifier contains the jet-spouted bed where the partial combustion reaction mainly occurs so that the gasifier was able to be operated at around optimum gasification temperature as high as 1350K without clinkering troubles. The reactor has been demonstrated to be an efficient dry-ash coal gasifier for the production of good quality gases.

Flow and Drying Characteristics of a Rotatinc Jet Spouted Bed

Flow and Drying Characteristics of a Rotatinc Jet Spouted Bed

QUALITY INTERACTION IN A JET SPOUTED BED DRYER FOR BIO-PRODUCTS

ABSTRACT 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.