vibration effect on particle bed aerodynamic behavior and thermal performance of black tea in fluidized bed dryers

Authors

m. sadeghi

m. h. khoshtaghaza

abstract

black tea sample was dried by a vibro-fluidized bed dryer to find its aerodynamic behavior and thermal performance during drying. the drying experiments were conducted at three different inlet air temperatures of 100, 115 and 130°c and fluidization condition at five vibration intensity levels of 0 (no vibration), 0.063, 0.189, 0.395 and 1.184. the results showed that bed channeling and defluidization problems were decreased in vibration condition. the vibration system decreased the requirement of minimum fluidization velocity of tea particles and this velocity reduced by increasing the vibration intensity. in the experiments, the maximum evaporation rate (13×10-3 kgv m-2 s-1) was at the vibration intensity of 1.184 and inlet air temperature of 130°c. also the minimum specific energy consumption (4953.785 kj kgv-1) was observed at 1.184 vibration intensity and 100°c inlet air temperature condition. based on lower minimum fluidization velocity and specific energy consumption, the vibration intensity of 1.184 and inlet air temperature of 100°c were recommended for drying black tea particles.

Upgrade to premium to download articles

Sign up to access the full text

Already have an account?login

similar resources

Analysis of Changes on Mean Particle Size in a Fluidized Bed using Vibration Signature

Vibration signals were measured in a lab-scale fluidized bed to investigate the changes in particle sizes. Experiments were carried out in the bed with a different mass fraction of coarser particles at different superficial gas velocities, and probe heights. The S-statistic test evaluates the dimensionless squared distance between two attractors reconstructed from time series of vibration signa...

full text

Particle Development in a Fluidized Bed Black Liquor Steam Reformer

Low-temperature gasification of black liquor is a new alternative to the conventional Tomlinson recovery boiler for recovering pulping chemicals and energy from black liquor in pulp and paper mills. This process can be carried out in a fluidized bed based on steam reforming at 600 C using indirect heat supplied via heat exchangers built into the fluid bed. As black liquor is injected into the b...

full text

Application of three Types of Dryers Namely Tunnel, Fluidized Bed, and Fluidized Bed with Microwave for Drying of Celery, Corn, and Sour Cherry: Experiments and Modeling (TECHNICAL NOTE)

In this paper, water content from celery, corn, and sour cherry were removed through tunnel, fluidized bed, and fluidized bed with microwave dryers. One day before performing the experiments, the fruits were put into a refrigerator and were ground into slices with average dimensions of 5×8×8 mm. For each experiment, 40 g of the samples were inserted in dryers. Moisture content in the samples wa...

full text

Numerical study of heat transfer in fluidized bed dryers by volume of fluid ‎method

The purpose of this study is numerical modeling of temperature variation of phases in a two phase regime in fluidized bed dryers including particles belonging to Group D of geldart classification. The mass transfer between phases is not taken into consideration in this modeling which has been assumed in three- dimensional, unsteady, and two-phase regime.To verify the modeling we consider the do...

full text

My Resources

Save resource for easier access later


Journal title:
journal of agricultural science and technology

Publisher: tarbiat modares university

ISSN 1680-7073

volume 14

issue 4 2012

Hosted on Doprax cloud platform doprax.com

copyright © 2015-2023