Aspects Concerning the Drying of Grained Biomaterials through Intensive Processes II. Malt Grain Drying in Fluidized Bed Formed by Inert Particles

2008 ◽  
Vol 59 (3) ◽  
pp. 283-291
Author(s):  
Monica Mares ◽  
Gabriela Isopencu ◽  
Cosmin Jinescu ◽  
Paul Vasilescu1 ◽  
Gheorghita Jinescu
Keyword(s):  
Experimental Study ◽  
Ambient Temperature ◽  
Fluidized Bed ◽  
Technological Process ◽  
Fixed Bed ◽  
Operating Conditions ◽  
Drying Process ◽  
Atmospheric Air ◽  
Grain Drying ◽  
Inert Particles

Present paper have like objective the experimental study regarding the intensification of the drying process of malt using like drying agent the atmospheric air at ambient temperature and at 45oC, in flotation-fluidized bed. To reduce the operating drying period by using the fluidization agent at 45oC, it was studied the drying in mixt bed, formed by inert particles (sand, dp=150mm, smashed malt, ) and wet malt grains (in flotation state). Comparing the drying periods and the final moistures obtained at the malt drying in fixed bed (fixed mixt bed) with those obtained in fluidized mixt bed was establish that: the drying in fluidized conditions conduce at an uniform final moisture product; the economical operating conditions for a final moisture (4 - 6%) imposed by the technological process.

Aspects concerning the Drying of Granular Biomaterials with Intensive Techniques I.Dynamics of Modified Fluidized Bed In the Presence of Inert Particles

2008 ◽  
Vol 59 (1) ◽  
pp. 79-87
Author(s):  
Alina Monica Mares ◽  
Gabriela Isopencu ◽  
Cosmin Jinescu
Keyword(s):  
Experimental Study ◽  
Thermal Degradation ◽  
Fluidized Bed ◽  
Inert Material ◽  
Dynamic Parameters ◽  
Drying Process ◽  
Dynamic Conditions ◽  
Inert Particles

Present paper has as objective the experimental study regarding the study on the dynamic parameters of modified fluidized bed. For the granular biomaterial processing by drying there are necessary intensifications techniques to avoid the thermal degradation. Present paper propose as intensification technique the modified fluidized bed (or flotation �fluidized bed) in which the granular biomaterial is mixed with inert material of small sizes. The purpose is to obtain the better dynamic conditions for the drying process.

scholarly journals IMPROVE THE PYROLYTIC GAS PRODUCTION BY USING THE CO-PYROLYSIS TECHNIQUE : AN EXPERIMENTAL STUDY

2021 ◽  
Vol 21 (2) ◽  
Author(s):  
Abo . Zahra A.I ◽  
M.K. Abd El- Wahab ◽  
M.A. Tawfik
Keyword(s):  
Energy Conversion ◽  
Fluidized Bed ◽  
Conversion Efficiency ◽  
Fixed Bed ◽  
Energy Conversion Efficiency ◽  
Gas Production ◽  
Operating Conditions ◽  
Energy Unit ◽  
Heating Value ◽  
Slow Pyrolysis

The target of the biomass co-pyrolysis is improvingthe heating value of the produced bio-products of a certain type of feedstock, besides disposal of more than one residue in the same time. Thus, this work aims to operate a local fabricated fixed-bed pyrolyzer to improve the pyrolytic gas yield produced by the ground pieces of three biomass residues namely Mango trees Pruning Logs (MPL), Sugarcane bagasse (SB) and Rice straw (RS) using an affordable slow pyrolysis technique. This work was carried out under slow pyrolysis conditions represented in final pyrolysis temperature of 400 °C, vapor residence time of 4 min, heating rate of 0.01-1 °C/s in full absence of oxygen. The pyrolytic gas production was assessed under different feedstock mixing ratios of (1:2:1), (1:1:2) and (2:1:1) as ratio of (RS: SB: MPL), particle lengths of 1-5, 10-15 and 20-25 mm, with and without sandy bed at the bottom of pyrolysis chamber as a fluidized bed. The obtained results showed that, using the fluidized fixed-bed pyrolyzer under slow co-pyrolysis conditions gave the optimum results where in, the pyrolytic gas concentration, gas yield, higher heating value of pyrolytic gasand energy conversion efficiency were 55%, 1.09 Nm3 /kg, 14.97 MJ/Nm3 and 85.43%, respectively, and 53.7%, 1.08 Nm3 /kg, 13.75 MJ/Nm3 ,77.71% in case of using the pyrolyzer without fluidized bed under the same operating conditions. So, the pyrolyzer with fluidized bed achieves an increment in the higher heating value and energy conversion efficiency by about 8.15% and 9.03%, respectivly over the pyrolyzer without fluidized bed.Furthermore, the cost per energy unit of pyrolytic gas produced by the fluidized bed pyrolyzer is lower than the common two fossil gaseous fuels of natural gas and LPG costs by about 28.57% and 80%, respectively.

Liquid-Solid Coupling Characteristics in the Fluidized Bed Evaporator for Tobacco Refined Liquid

2014 ◽  
Vol 686 ◽  
pp. 522-528
Author(s):  
Feng Lan Wang ◽  
Yuan Jun Yao ◽  
Fa Yun Gong ◽  
Fang Ping Ye ◽  
Wen Jie Qi
Keyword(s):  
Fluidized Bed ◽  
Flow Characteristics ◽  
Operating Conditions ◽  
Maximum Speed ◽  
Force Model ◽  
Liquid Density ◽  
Two Phase ◽  
Viscous Term ◽  
Inert Particles ◽  
Coupling Characteristics

Consider a two-phase liquid-solid coupling effect, using Euler - Euler two-fluid model is solved using standard viscous term with k-ε model and the velocity pressure coupling a simple algorithm to simulate liquid-solid two-phase flow characteristics of the fluid flow method bed, the applicability of the model to assess the drag. Different effects of a two-stage flow characteristics of fluidized bed flow characteristics, fluid and operating conditions affect the physical properties of the paper. We found from the simulation is the use of different drag coefficient models will greatly affect the results, which drag force model Syamlal - O'Brien is more suited to study the coupling characteristics of liquid flow in a fluidized bed of solid than Gidaspow. And velocity of the inert particles increase with the viscosity of the liquid increase. Further, the maximum speed of the inert particles in a fluidized bed by a central, which means the settling velocity in the fluidized bed of inert particles is the slowest; increasing liquid density and lead to increased speed of the inert particles; volume of the inert particles Score changes can also affect the speed of the particle velocity distribution, and there is no linear relationship.

Torrefaction of Tomato Peel Residues in a Fluidized Bed of Inert Particles and a Fixed-Bed Reactor

2016 ◽  
Vol 30 (6) ◽  
pp. 4858-4868 ◽  
Author(s):  
Paola Brachi ◽  
Francesco Miccio ◽  
Michele Miccio ◽  
Giovanna Ruoppolo
Keyword(s):  
Fluidized Bed ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Inert Particles

scholarly journals Modeling of the management of the microwave grain drying process

2019 ◽  
Vol 110 ◽  
pp. 02142
Author(s):  
Sergey Morozov ◽  
Konstantin Kuzmin ◽  
Denis Pogodin ◽  
Lyudmila Kochetkova ◽  
Anna Rogozhina
Keyword(s):  
Mathematical Model ◽  
Technological Process ◽  
Environmentally Friendly ◽  
Drying Process ◽  
Grain Drying

The article discusses the VisSim program, which allows simulating microwave grain drying process. Its capabilities and methods of development are shown, the structure of a mathematical model for management of the drying process and individual blocks is provided. It is noted that offered modeling of the grain drying process makes it possible to evaluate it as a technological process, as well as to show the possibility of its optimization. It should be noted that this method is environmentally friendly and less energy intensive than others.

Characterization and Utilization of a Commercial Clay for Ammonia Adsorption Influence of Operating Parameters on Gas Retaining

2008 ◽  
Vol 59 (10) ◽  
Author(s):  
A. Violeta Ursu ◽  
Fabrice Gros ◽  
Denisa I. Nistor ◽  
Gholamreza Djelveh
Keyword(s):  
Mass Transfer ◽  
Fluidized Bed ◽  
Fixed Bed ◽  
Operating Conditions ◽  
Operating Parameters ◽  
Clay Layer ◽  
Natural Clay ◽  
Ammonia Adsorption ◽  
Sodium Bentonite ◽  
Nh3 Adsorption

The aim of this paper is to study the use of a mixture of commercial clay namely K10 and a natural Romanian sodium bentonite in the adsorption of NH3 contained in air using fixed and fluidized bed gas-solid reactors. Qualitative (DRX) and quantitative (XPS, DTG) analysis were performed. Clays were agglomerated and treated with NH3. Adsorption isotherms were determined under several operating conditions. Results showed that after 70 minutes of ammonization, activated agglomerated clay exhibits a superior capacity of adsorption (2.09 mmoles NH3/g clay instead of 1.057 mmoles/g clay for natural clay). The saturation duration depends on the adsorbent bed state (fixed or fluidized bed). The mass transfer is better in fluidized bed, the clay layer being saturated more rapidly compared to the fixed bed.

Experimental Investigation on Flow Patterns of Cylindrical-Conical Spout-Fluidizing Bed

2011 ◽  
Vol 354-355 ◽  
pp. 338-343
Author(s):  
Qian Jun Li ◽  
Dong Ping Zhang
Keyword(s):  
Flow Pattern ◽  
Fluidized Bed ◽  
Fixed Bed ◽  
Ccd Camera ◽  
Flow Patterns ◽  
Operating Conditions ◽  
Hydrodynamic Characteristics ◽  
Experimental Investigations ◽  
Bed Height ◽  
Bed Materials

Experimental investigations on hydrodynamic characteristics of cylindrical pressurized spout-fluidizing bed were carried out. Two kinds of millet were used as bed materials. The operational pressure is 0.1MPa~0.4MPa (absolutely pressure). Five distinct flow patterns, i.e, fixed bed(FB), jet in fluidized bed with bubbles(JFB), jet in fluidized bed with slugging(JFS), spout with aeration(SA) and spout-fluidizing bed(SF) were identified. Effects of the static bed height and operational pressure on the flow pattern map were particularly studied. Typical flow pattern images obtained by a high- resolution digital CCD camera were presented for classifying these flow patterns. Typical flow pattern maps were plotted for describing the transitions between flow patterns with operating conditions

Theoretical Analysis of Fluidized-Bed Reactor for Dimethyl Ether Synthesis from Syngas

2003 ◽  
Vol 1 (1) ◽  
Author(s):  
Wen-Zhi Lu ◽  
Li-Hua Teng ◽  
Wen-De Xiao
Keyword(s):  
Mass Transfer ◽  
Fluidized Bed ◽  
Dimethyl Ether ◽  
Fixed Bed ◽  
Fluidized Bed Reactor ◽  
Slurry Reactor ◽  
Operating Conditions ◽  
Fixed Bed Reactor ◽  
Dme Synthesis ◽  
Co Conversion

Dimethyl ether (DME) is regarded as an environmentally benign fuel for vehicles. Two kinds of reactor technologies for DME synthesis have been proposed by previous researchers: the fixed-bed and the slurry reactor. As the reactions are highly exothermic and the temperature window of the catalyst is very narrow, the fixed-bed reactor provides a limited heat removal capability and a low conversion of the syngas. The slurry reactor can provide an effective temperature control but a very high inter-phase mass transfer resistance is added by the liquid medium. The Fluidized bed reactor can be an ideal reactor for DME synthesis as it possesses both high heat and mass transfer efficiencies. In this paper, a two-phase model is used to theoretically analyze the DME synthesis in a fluidized bed reactor, with both phases assumed to be in plug flow and taking into account the changes in bubble diameter resulting from the reaction. Three reactions take place simultaneously when DME is manufactured from the syngas (H2 + CO): a) CO+2H2 = CH3OH; b) 2CH3OH = DME+H2O; and c) CO+H2O = CO2+H2. The simulation shows that, at the reactor outlet, the equilibrium approaches of the three reactions are 0.32, 0.1, and 0.61, respectively. When H2/CO=1.0, the CO conversion and DME selectivity in a fluidized bed reactor are 62% and 95%, while those in a fixed-bed reactor are 9% and 86%. In a slurry reactor, the CO conversion and DME selectivity are 17% and 70%, respectively. Therefore, the fluidized-bed is the most promising candidate reactor for conducting the DME synthesis from syngas. Effects of the operating conditions on the performance of DME synthesis in the fluidized-bed reactor are discussed in details. The optimal H2/CO ratio is between 1.0-1.5, and increasing the pressure is shown to improve the reactor performance.

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