RESEARCH ON SHREDDED BIOMASS DRYING IN A VIBRATING FLUIDIZED BED DRYER

The article presents aspects related to energy potential of the shredded biomass from agricultural secondary production, coming from maintenance operations to cutting trees and vines and an original solution of dryer with vibrating fluidized bed with continuous operation equipped with adjustments of the transit time of biomass in the dryer. Also, it was analysed the dynamic behaviour of the biomass tray as well as of a biomass particle for the variant of vibrating fluidized bed.

A Statistical Optimization of Convective Drying of Corn Kernels in a Fluidized Bed Dryer

Food storage is an essential process for food security and it needs to be free from any biological contamination. For the same, agriculture produce needs to be completely dried before sending for storage. The present work discusses a systematic approach to model drying parameters of corn kernels in a fluidized bed dryer. Experiments were designed according to a higher level Box-Behnken design combined with response surface methodology. Four parameters were chosen to vary namely: amount of corn kernels (50 -100 gm), temperature of drying (50 – 80⁰C), air velocity (6.01 – 8.08 m/s) and drying time (30 – 60 min) for experiments as well as for the model. The reduction of moisture content was determined after each experiment for understanding the behaviour of drying process. The model equations were obtained and surface response plots were generated in MATLAB to investigate the drying behaviour of corn kernels with all four parameters. Ultimately, this work represents the dependence of moisture removal on all four parameters chosen with efficient use of response surface methodology and Box-Behnken design. Analysis of variance confirmed that velocity of air and amount of corn are the most significant parameters along with temperature and time of drying. Optimum condition with the model were obtained as 50 gm of corn kernels, 80 ⁰C drying temperature, 8 m/sec velocity of air, and 60 min time of drying for 73.3 % of moisture from corn kernels.

Heat transfer analysis in fluidized bed dryer with heat exchanger pipe for corn material

This research aims to know the heat transfer process on the fluidized bed dryer for corn material. In this study conducted observations on the temperature and heat produced during the drying process, with three different pipe heat exchanger: spiral, parallel, and combination; The air of the air was 2 m/s, 4 m/s, and 6 m/s and the mass of corn material was1.5 kg with an initial moisture content of 24%. Test results showed that the highest-produced temperature in the combination heat exchanger pipe with a drying room temperature averaged 54°C. The value of the highest convection coefficient of heat transfer in the combination heat exchanger pipe flow treatment with the air velocity of 6 m/s by 29.4 W/m2K. The heat energy that enters at the treatment of combination heat exchanger pipe with the air speed of 6 m/s by 1774 Watts. Heat energy is lost through the highest wall drying chamber at the combination heat exchanger pipe flow treatment with the air velocity of 6 m/s by 409 Watts. The heat energy used is 335 Watts to dry the highest material in the combination heat exchanger pipe flow treatment with the air speed of 6 m/s.

Analysis of Heat Energy on the Drying Process of Paddy Using Fluidized Beds Dryer

The purpose of this study was to determine the amount of heat energy in the paddy drying process using a fluidized bed dryer. The method used in this research was an experimental method using an energy balance. This test was carried out using a fluidized beds dryer, with paddy material, where the paddy was dried at a certain temperature with 3 mass treatments, namely 5, 6 kg, and 7 kg with an air velocity of 21 m/s. The results showed that the total energy that enters the drying chamber for a mass of 5 kg material is 1,022 kJ with a useful energy of 1.339 kJ. The energy that enters the drying chamber for a mass of 6 kg is 1,043 kJ with a useful energy of 2.192 kJ. For a mass of 7 kg of material, the energy that enters the drying chamber is 1,187 kJ with a useful energy of 3.578 kJ.

THE INFLUENCE OF STIRRER ON THE DRYING OF WHEAT PARTICLES IN A FLUIDIZED BED AT LOW AIR VELOCITY

This study represents an attempt to reduce the drying time of wet grain wheat of the fluidized bed dryer (FBD), using straight blades, and debates the effect of stirrer on the whole drying time at different static bed heights. Experiments for FBD were conducted at the low velocity of air supply (1.45 cm/s) with moisture content for grain wheat 12% and ambient temperature of 37°C for each static bed height (9, 12, and 15 cm). FBD was made from a glass cylindrical column with inside diameter 4.6 cm, outside diameter (5.2 cm) and length (116 cm). The results showed an enhancement of (12- 20.5%) in the total drying time for bed height (9 and 15) cm, respectively. Also, increasing bed height from 9 cm to 15 cm possesses no influence on the equilibrium content of moisture in both techniques of drying either stirred fluidized bed or conventional fluidized bed.

Development of a Fluidized Bed Dryer for Drying of a Sago Bagasse

Sago is an essential source of starch for some regions in the third and developing world. However, the sago processing industry has been producing a large amount of sago waste, and the untreated waste is usually disposed to the nearest river. It not only leads to the environmental problem, but it is illegal under the Environmental Quality Act 1974. Since the sago waste still has high starch content, which is 58%, it can be converted to high value-added products such as poultry feed. However, before being converted to other products, the sago must be dried to remove the moisture content to prevent any bacteria growth and ensure safety health issues have been observed. Recently, drying of sago bagasse using a fluidized bed dryer (FBD) has gained attention since the dry rate of the material is considerably faster compared to other methods. Due to that reason, the drying of the sago bagasse in the FBD is studied using computational fluid dynamic as it can be executed in a short period of time compared to the experimental approach. The FBD model was developed using ANSYS© Fluent academic version 19.2. The effect of the hot air feed temperature; T=50, 60, 70, and 80°C and velocity of hot air feed; v=1-4 m/s on the sago’s behavior and performance of fluidization profile were studied. The simulation results showed that the high temperature and air feed velocity would result in a rapid drying rate. Besides, the optimum drying rate was at T=60°C with the v=4 m/s as these conditions give a shorter drying time to achieve of final 10% moisture content. It also has the added advantages of reducing the power energy and cost supply. These optimal conditions are very crucial and should be consider as the dried sago bagasse tend to be retrograded when a higher temperature is applied.