The Experts below are selected from a list of 27 Experts worldwide ranked by ideXlab platform
F. C. Lockwood - One of the best experts on this subject based on the ideXlab platform.
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Pulverized-coal flame stability: effect of the Burner Quarl cooling
Chemical Engineering Science, 1991Co-Authors: Mohamed Hassan, M. A. Ismail, F. C. LockwoodAbstract:Abstract This paper presents flame stability data for a pulverized-coal furnace having a water-cooled Quarl and burning U.K. Gedling coal. The water-cooled Quarl has the same geometry as that of a conventional refractory Quarl which was the subject of a previous study. The influences of swirl number, excess air, momentum ratio and Burner load on flame stability have been studied. It was observed that flame stability generally improved at high swirl numbers, high excess air levels and low ratios of primary to secondary momenta. The stability performance of the water-cooled Quarl was significantly inferior to that of the corresponding refractory Quarl. However, the elimination of the Quarl slagging represents an important advantage of the water-cooled Quarl.
Mohamed Hassan - One of the best experts on this subject based on the ideXlab platform.
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Pulverized-coal flame stability: effect of the Burner Quarl cooling
Chemical Engineering Science, 1991Co-Authors: Mohamed Hassan, M. A. Ismail, F. C. LockwoodAbstract:Abstract This paper presents flame stability data for a pulverized-coal furnace having a water-cooled Quarl and burning U.K. Gedling coal. The water-cooled Quarl has the same geometry as that of a conventional refractory Quarl which was the subject of a previous study. The influences of swirl number, excess air, momentum ratio and Burner load on flame stability have been studied. It was observed that flame stability generally improved at high swirl numbers, high excess air levels and low ratios of primary to secondary momenta. The stability performance of the water-cooled Quarl was significantly inferior to that of the corresponding refractory Quarl. However, the elimination of the Quarl slagging represents an important advantage of the water-cooled Quarl.
M. A. Ismail - One of the best experts on this subject based on the ideXlab platform.
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Pulverized-coal flame stability: effect of the Burner Quarl cooling
Chemical Engineering Science, 1991Co-Authors: Mohamed Hassan, M. A. Ismail, F. C. LockwoodAbstract:Abstract This paper presents flame stability data for a pulverized-coal furnace having a water-cooled Quarl and burning U.K. Gedling coal. The water-cooled Quarl has the same geometry as that of a conventional refractory Quarl which was the subject of a previous study. The influences of swirl number, excess air, momentum ratio and Burner load on flame stability have been studied. It was observed that flame stability generally improved at high swirl numbers, high excess air levels and low ratios of primary to secondary momenta. The stability performance of the water-cooled Quarl was significantly inferior to that of the corresponding refractory Quarl. However, the elimination of the Quarl slagging represents an important advantage of the water-cooled Quarl.
Reinhold Kneer - One of the best experts on this subject based on the ideXlab platform.
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development of an oxycoal swirl Burner operating at low o2 concentrations
Fuel, 2009Co-Authors: Peter Heil, Dobrin Toporov, Hannes Stadler, Stefan Tschunko, Malte Forster, Reinhold KneerAbstract:This work is to clarify the underlying mechanisms of burning pulverised coal in a mixture of CO2/O2CO2/O2. The performance of two different Burner designs, single central orifice-type (SCO) and single annular orifice-type (SAO), under oxycoal conditions was examined in a down-fired test facility. Based on detailed in-flame measurements, combined with numerical simulations, the main parameters influencing the stability of a CO2/O2CO2/O2 pulverised coal swirl flame were investigated. The oxycoal flame was stabilised at the Burner Quarl by: increasing the O2 concentration above 34 vol% without changes to the air-firing Burner design and by modifications of the Burner geometry thus changing its aerodynamics. The modification of the Burner allowed a decrease of the O2 concentrations to 23 vol% for SCO Burner and to less than 21 vol% for SAO Burner. Comprehensive measurement data for axial and tangential velocity, flue gas temperature and oxygen concentration for stable oxy-firing at 21 vol% O2 is presented. The results reported can be used as a guideline for a development of an industrial swirl Burner capable of stable operation in both regimes, namely: air and oxycoal.
Masudi Houshang - One of the best experts on this subject based on the ideXlab platform.
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COMBUSTION CHARACTERIZATION OF COAL-WATER SLURRY FUEL PREPARED FROM PLANT COAL AND RECOVERED COAL FINES
National Energy Technology Laboratory (U.S.), 1997Co-Authors: Masudi HoushangAbstract:In the process of coal cleaning operations, a significant amount of coal is washed away as waste into the ponds. Clearly, such a large quantity of dumped coal fines has a detrimental effect on the environment. This investigation presents in innovative approach to recover and utilize waste coal fines from the preparation plant effluent streams and tailing ponds. Due to the large moisture content of the recovered coal fines, this study is focused on the utilization of coal fines in the coal-water slurry fuel (CWSF). The CWSF consists of 53.3% weight solids with a viscosity of less than 500 centipoise and 80-90% of solids passing 200 mesh. The 53.3% weight solids constitute a blend of 15% effluent recovered coal fines and 85% clean coal. It is the authors premise that a blend of plant coal and recovered waste coal fines can be used to produce a coal-water slurry fuel with the desired combustion characteristics required by the industry. In order to evaluate these characteristics the coal-water slurry fuel is fired in a test furnace at three firing rates (834,330 Btu/hr, 669,488 Btu/hr and 508,215 Btu/hr) with three different Burner settings for each firing rate. Combustion tests were conducted to determine the range of secondary air swirl required to maintain a stable combustion flame. Results obtained during the flame stability testing show no significant effect of swirl settings on Nox, SO2 and CO2 for three combustion tests (834, 330 Btu/hr, 669, 488 Btu/hr, 508 215 Btu/hr). At each of the two higher firing rates, combustion was relatively complete regardless of swirl settings, therefore, Burner settings may be adjusted to provide a visually stable flame without concern for higher carbon in ash as a function of Burner settings. The parameters affecting flame stability are mainly coal particle size, volatile matter, ash content and excess air. Tests conducted at three different locations (top, Middle, Bottom) revealed that the gaseous concentrations such as Nox, SO2 and CO2 were a function of residence time for each of the firing rates. Effect of swirl settings on Nox for three firing rates were investigated. It was found that the variation of Nox concentrations with respect to the change in swirl numbers was significant. But, the variation of Nox Concentration with respect to firing rates was found to be consistent with the increase in firing rates. The flame stability was accessed by the visual observation of the flame with relation to the Burner Quarl
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Combustion Characterization of Coal Fines Recovered from the Handling Plant
National Energy Technology Laboratory (U.S.), 1996Co-Authors: Masudi Houshang, Samudrala, Surender Rao, Chenevert Lisa, Cornelius Christopher, Dwivedi S. N.Abstract:Effect of swirl settings on NO{sub x} for three firing rates were investigated. It was found that the variation of NO{sub x} concentrations with respect to the change in swirl numbers was significant. But, the variation of NO{sub x} Concentration with respect to firing rates was found to be consistent with the increase in firing rates. The flame stability was accessed by the visual observation of the flame with relation to the Burner Quarl
