One significant factor in the operation of a fluidized bed combustor is the manner in which coal particles disperse and mix with the bed material upon entering the bed. A thermal tracing technique was used to study the mixing characteristics in a 1/4 scale model of a pressurized bubbling fluidized bed combustor. Particles cooled by liquid nitrogen are injected into the bed in the same way that ...

Fluidized bed techniques are employed in coal combustion power plants, because they allow for the use of low-quality fuel and result in low pollutant emissions. The most important dynamical difference between fluidized beds and normal combustion chambers, is that the former are characterized by a significant loading of carbon, usually absent in conventional plants. Fluidized beds are remarkably...

conclusions results indicated that annular fluidized bed reactor’s adsorbers are useful techniques for vocs adsorption. comparison of two particle ranges indicates that in all concentrations and all flow rates of the experiments, smaller particle size adsorption are better. in superficial velocity above the minimum fluidization velocity, pressure drop of fluidized beds are less than the pressur...

Natural substrates like sand, soil, leaf litter and snow vary widely in penetration resistance. To search for principles of appendage design in robots and animals that permit high performance on such flowable ground, we developed a ground control technique by which the penetration resistance of a dry granular substrate could be widely and rapidly varied. The approach was embodied in a device co...

Pullulanase from Bacillus acidopullulyticus was purified on a packed bed and a fluidized bed of calcium alginate beads. The binding of enzyme activity to the medium was found to follow Langmuir isotherm pattern. The maximum binding capacity was 1476 U ml(-1) matrix and the dissociation constant was 142 U ml(-1). The dynamic binding capacities at 5% breakthrough in the packed and fluidized beds ...

The paper presents the method of on-line diagnostics of the bed temperature controller for the fluidized bed boiler. Proposed solution is based on the methods of statistical process control. Detected decrease of the bed temperature control quality is used to activate the controller self-tuning procedure. The algorithm that provides optimal tuning of the bed temperature controller is also propos...

The efficiency of fluidized bed reactors depends on bubble distribution, bubble size and bubble velocity within the reactor. The sizes and size distributions of particles used in the bed may lead to different bubble behaviour. The objective of this work is to study the influence of particle size distribution on bubble behaviour. The results from the experiments will be used for validation of CF...

In order to improve the traditional freezing crystallization process of calcium nitrate in nitric phosphate process, crystal growth experiments by adding Ca(NO3)2·4H2O seeds in supersaturated calcium nitrate solution in a Circulating Fluidized Bed (CFB) crystallizer were carried out on crystal growth kinetics. The results showed that the growth of C...

In this work we have tested the fluidized bed desulfurization performance of lime particles obtained by means of a proprietary limestone slow calcination pre-treatment technique. This performance was compared to that of the parent untreated limestone particles. The occurrence of particle fragmentation and attrition during the fluidized bed operation was also investigated with a specific test pr...

In this paper computational analysis of circulating fluidized bed combustion using the fluent software is analysed. This work is concerned about gas–solid two-phase mixtures flowing upwards through the fast beds. The procedures studied are applicable to all types of fluidized-bed boilers. The type of information resulting from various ways of analyzing the pressure and temperature in fluidized ...