scholarly journals Multi Solid Fluidized Bed Boilers and Multiphase Flow Problems

1988 ◽  
Vol 2 (4) ◽  
pp. 292-298
Author(s):  
Yasuo KOJIMA ◽  
Tatsuo MII
Author(s):  
Ashesh Chattopadhyay ◽  
V. M. Krushnarao Kotteda ◽  
Vinod Kumar ◽  
William Spotz

A framework is developed to integrate the existing MFiX (Multiphase Flow with Interphase eXchanges) flow solver with state-of-the-art linear equation solver packages in Trilinos. The integrated solver is tested on various flow problems. The performance of the solver is evaluated on fluidized bed problems and observed that the integrated flow solver performs better compared to the native solver.


2015 ◽  
Vol 14 (4) ◽  
pp. 164-172 ◽  
Author(s):  
Jacek M. Łączny ◽  
Sebastian Iwaszenko ◽  
Krzysztof Gogola ◽  
Andrzej Bajerski ◽  
Tomasz Janoszek ◽  
...  

Author(s):  
A. K. M. Monayem Mazumder ◽  
Ting Wang ◽  
Jobaidur R. Khan

To help design a mild-gasifier, a reactive multiphase flow computational model has been developed in Part 1 using Eulerian-Eulerian method to investigate the thermal-flow and gasification process inside a conceptual, hybrid entrained-flow and fluidized-bed mild-gasifier. In Part 2, the results of the verifications and the progressive development from simple conditions without particles and reactions to complicated conditions with full reactive multiphase flow are presented. Development of the model starts from simulating single-phase turbulent flow and heat transfer in order to understand the thermal-flow behavior, followed by introducing seven global, homogeneous gasification reactions progressively added one equation at a time. Finally, the particles are introduced, and heterogeneous reactions are added in a granular flow field. The mass-weighted, adiabatic flame temperature is validated through theoretical calculation and the minimum fluidization velocity is found to be close to Ergun’s correlation. Furthermore, the predicted exit species composition is consistent with the equilibrium values.


2020 ◽  
Vol 24 (5 Part A) ◽  
pp. 2665-2675
Author(s):  
Songsong Zhang ◽  
Qian Du ◽  
Guoli Qi

Particle size distributions, concentrations, morphological characteristics, and elemental compositions of eight fluidized bed boilers with different capacities and different dust collectors were determined experimentally. The PM2.5 particle concentration and mass concentration were monitored in real-time before and after the boiler dust collector by electric low pressure impactor, and the physical and chemical properties of PM2.5 were analyzed by membrane sampling. We found that the PM2.5 particle concentration produced by industrial fluidized bed boilers displayed bimodal distributions, peaking at 0.2 ?m and 0.76 ?m, the formed mechanism of these two parts particles is vaporization-condensation of mineral matter and residual ash particles and the adsorbent wear or tear. Mass concentration exhibits a single peak characteristic with a peak at 0.12 ?m. The removal efficiency for PM2.5 of dust collectors varies with different dust removal mechanisms. The electrostatic precipitator and bag filter have high dust removal efficiency, and the water film dust collector has low dust removal efficiency. The normal operation of the bag filter has a great influence on the dust removal efficiency. The physical and chemical properties of PM2.5 showed that the single-particle morphology was mainly composed of irregular particles, containing a small amount of solid spherical particles and more agglomerates. The content of Si and Al in PM2.5 elemental analysis is the highest, which decreases after a dust collector. Some fluidized bed boilers use desulfurization in the furnace, which has great influence on the mass concentration of Ca and S elements, and the lowest Hg content in trace elements, about a few ppm. <br><br><font color="red"><b> This article has been corrected. Link to the correction <u><a href="http://dx.doi.org/10.2298/TSCI200901242E">10.2298/TSCI200901242E</a><u></b></font>


2004 ◽  
Vol 8 (2) ◽  
pp. 107-126 ◽  
Author(s):  
Jaakko Saastamoinen

New process concepts in energy production and biofuel, which are much more reactive than coal, call for better controllability of the combustion in circulating fluidized bed boilers. Simplified analysis describing the dynamics of combustion in fluidized bed and circulating fluidized bed boilers is presented. Simple formulas for the estimation of the responses of the burning rate and fuel inventory to changes in fuel feeding are presented. Different changes in the fuel feed, such as an impulse, step change, linear increase and cyclic variation are considered. The dynamics of the burning with a change in the feed rate depends on the fuel reactivity and particle size. The response of a fuel mixture with a wide particle size distribution can be found by summing up the effect of different fuel components and size fractions. Methods to extract reaction parameters form dynamic tests in laboratory scale reactors are discussed. The residence time of fuel particles in the bed and the resulting char inventory in the bed decrease with increasing fuel reactivity and differences between coal and biomass is studied. The char inventory affects the stability of combustion. The effect of char inventory and oscillations in the fuel feed on the oscillation of the flue gas oxygen concentration is studied by model calculation. A trend found by earlier measurements is explained by the model.


2021 ◽  
Vol 14 (4) ◽  
Author(s):  
Jacek M. Łączny ◽  
Sebastian Iwaszenko ◽  
Krzysztof Gogola ◽  
Andrzej Bajerski ◽  
Tomasz Janoszek ◽  
...  

2020 ◽  
Vol 24 (6 Part A) ◽  
pp. 3859-3859
Author(s):  
E Editorial

Requests that it is necessary to clearly define names of two Corresponding authors of the paper EXPERIMENTAL STUDY ON PRODUCTION AND EMISSION CHARACTERISTICS OF PM2.5 FROM INDUSTRIAL FLUIDIZED BED BOILERS by Songsong ZHANGa, Qian DUb* , and Guoli QIa <br><br><font color="red"><b> Link to the corrected article <u><a href="http://dx.doi.org/10.2298/TSCI190828001Z">10.2298/TSCI190828001Z</a></b></u>


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