One of the challenges that chemical engineers face is placing solid materials in contact with gases to generate certain reactions. One of the options is to use a fluidised bed, consisting of a vertical cylinder with a perforated plate inside where solid particles are introduced using pressurised air.
This way, the solid particles are suspended, and behave much like boiling water. Solids behaving like a liquid depend on the speed of the air stream, making it key to achieving the desired behaviour. With insufficient air, the particles don’t move, but with too much the opposite happens, and they are carried away by the air stream.
Fluidised beds have relevant environmental applications because they allow the gasification of biomass to produce energy. That is, producing fuel gas from crushed biomass which can then be used for energy production. According to one of the authors of the study, Mercedes de Vega from the Energy System Engineering Group of the department of Thermal and Fluid Engineering of the UC3M, using fluidised beds as chemical reactors allows for a more efficient conversion by achieving high mixing degrees and high exchange rates of mass and heat.
This renewable source has great potential in Spain, especially in processes of co-combustion, direct combustion, and gasification. The applications are mainly industrial, open to be used in motors for the production of electricity, in gas turbines, drying processes, as well as in the pharmaceutical industry for the treatment of powder.
The study analyses the behaviour of a new bed designed with a rotating base. The base consists of a perforated plate where holes represent just 1% of its total area. The study evaluates the performance of this new design, considering the increase in pressure and the quality of the fluidisation. It also analyses the effect of the rotation speed of the perforated plate on the performance of the fluidised bed. This type of beds can usually present problems such as agglomeration of solid particles and points of high temperature. But one of the most important conclusions determined that the rotating perforated plate reduces these problems by maintaining a very uniform fluidisation.
The researchers now propose, for future investigations, to study different rotation speeds over a hundred revolutions per minute, and to alter the configuration of the holes in the plate. Celia Sobrino, author of the study, states that the new rotating distribution plate produces smaller bubbles inside the fluidised bed and distributes them better, while improving the efficiency of the conversion in gasification applications.
The study ‘Fluidization of Group B particles with a rotating distributor’ carried out by the Energy System Engineering Group of the department of Thermal and Fluid Engineering of the Carlos III University of Madrid has been published in the journal Powder technology.
Oficina de Información Científic | alfa
A big nano boost for solar cells
18.01.2017 | Kyoto University and Osaka Gas effort doubles current efficiencies
Multiregional brain on a chip
16.01.2017 | Harvard John A. Paulson School of Engineering and Applied Sciences
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).
Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...
10.01.2017 | Event News
09.01.2017 | Event News
05.01.2017 | Event News
18.01.2017 | Materials Sciences
18.01.2017 | Information Technology
18.01.2017 | Ecology, The Environment and Conservation