The Experts below are selected from a list of 1569 Experts worldwide ranked by ideXlab platform
Zhi-yong Tang - One of the best experts on this subject based on the ideXlab platform.
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trace elements mn cr pb se zn cd and hg in emissions from a Pulverized Coal Boiler
Fuel Processing Technology, 2004Co-Authors: Yaji Huang, Zhaoping Zhong, Rui Xiao, Zhi-yong TangAbstract:The concentrations of seven trace elements (Mn, Cr, Pb, Se, Zn, Cd, Hg) in raw Coal, bottom ash and fly ash were measured quantitatively in a 220 tons/h Pulverized Coal Boiler. Factors affecting distribution of trace elements were investigated, including fly ash diameter, furnace temperature, oxygen concentration and trace elements' characteristics. Modified enrichment factors show more directly element enrichment in combustion products. The studied elements may be classified into three groups according to their emission features: Group 1: Hg, which is very volatile. Group 2: Pb, Zn, Cd, which are partially volatile. Group 3: Mn, which is hardly volatile. Se may be located between groups 1 and 2. Cr has properties of both Groups 1 and 3. The smaller the diameter of fly ash, the higher is the relative enrichment of trace elements (except Mn). Fly ash shows different adsorption mechanisms of trace elements and the volatilization of trace elements rises with furnace temperature. Relative enrichments of trace elements (except Mn and Cr) in fly ash are larger than that in bottom ash. Low oxygen concentration will not always improve the volatilization of trace elements. Pb forms chloride more easily than Cd during Coal combustion.
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Occurrence and volatility of several trace elements in Pulverized Coal Boiler.
Journal of Environmental Sciences-china, 2004Co-Authors: Yaji Huang, Zhaoping Zhong, Rui Xiao, Zhi-yong TangAbstract:: The contents of eight trace elements(Mn, Cr, Pb, As, Se, Zn, Cd, Hg) in raw Coal, bottom ash and fly ash were measured in a 220 t/h Pulverized Coal Boiler. Factors affecting distribution of trace elements were investigated, including fly ash diameter, furnace temperature, oxygen content and trace elements' characters. One coefficient of Meij was also improved to more directly show element enrichment in combustion products. These elements may be classified into three groups according to their distribution: Group 1: Hg, which is very volatile. Group 2: Pb, Zn, Cd, which are partially volatile. Group 3: Mn, which is hardly volatile. Se may be located between groups 1 and 2. Cr has properties of both group 1 and 3. In addition, the smaller diameter of fly ash, the more relative enrichment of trace elements (except Mn). The fly ash showed different adsorption mechanisms of trace elements and the volatilization of trace elements rises with furnace temperature. Relative enrichments of trace elements(except Mn and Cr) in fly ash are larger than that in bottom ash. Low oxygen content can not always improve the volatilization of trace elements. Pb is easier to form chloride than Cd during Coal combustion. Trace elements should be classified in accordance with factors.
Dong Soo Kang - One of the best experts on this subject based on the ideXlab platform.
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numerical and experimental investigations on the gas temperature deviation in a large scale advanced low nox tangentially fired Pulverized Coal Boiler
Fuel, 2013Co-Authors: Hoyoung Park, Sehyun Baek, Dong Soo KangAbstract:Abstract This paper describes the numerical and experimental investigations of the gas temperature deviation in the crossover pass of a large scale, advanced low NOx, tangentially fired Pulverized Coal Boiler. Major attention was paid to the region of the final super-heater where the tube ruptures occasionally had been occurred due to the tube overheating. Computational Fluid Dynamics (CFD) simulation and measurements of gas temperature just in front of the final super-heater showed the gas temperature distribution was biased to the left, lower region of that heater. It was found that this deviation is originated from the residual swirl flow in the upper furnace. To alleviate the gas temperature deviation, the changes in yaw angles of over-fire air have been suggested and the field tests carried out to identify their effects on that deviation. The test showed it is quite effective method to reduce that deviation.
Yaji Huang - One of the best experts on this subject based on the ideXlab platform.
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trace elements mn cr pb se zn cd and hg in emissions from a Pulverized Coal Boiler
Fuel Processing Technology, 2004Co-Authors: Yaji Huang, Zhaoping Zhong, Rui Xiao, Zhi-yong TangAbstract:The concentrations of seven trace elements (Mn, Cr, Pb, Se, Zn, Cd, Hg) in raw Coal, bottom ash and fly ash were measured quantitatively in a 220 tons/h Pulverized Coal Boiler. Factors affecting distribution of trace elements were investigated, including fly ash diameter, furnace temperature, oxygen concentration and trace elements' characteristics. Modified enrichment factors show more directly element enrichment in combustion products. The studied elements may be classified into three groups according to their emission features: Group 1: Hg, which is very volatile. Group 2: Pb, Zn, Cd, which are partially volatile. Group 3: Mn, which is hardly volatile. Se may be located between groups 1 and 2. Cr has properties of both Groups 1 and 3. The smaller the diameter of fly ash, the higher is the relative enrichment of trace elements (except Mn). Fly ash shows different adsorption mechanisms of trace elements and the volatilization of trace elements rises with furnace temperature. Relative enrichments of trace elements (except Mn and Cr) in fly ash are larger than that in bottom ash. Low oxygen concentration will not always improve the volatilization of trace elements. Pb forms chloride more easily than Cd during Coal combustion.
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Occurrence and volatility of several trace elements in Pulverized Coal Boiler.
Journal of Environmental Sciences-china, 2004Co-Authors: Yaji Huang, Zhaoping Zhong, Rui Xiao, Zhi-yong TangAbstract:: The contents of eight trace elements(Mn, Cr, Pb, As, Se, Zn, Cd, Hg) in raw Coal, bottom ash and fly ash were measured in a 220 t/h Pulverized Coal Boiler. Factors affecting distribution of trace elements were investigated, including fly ash diameter, furnace temperature, oxygen content and trace elements' characters. One coefficient of Meij was also improved to more directly show element enrichment in combustion products. These elements may be classified into three groups according to their distribution: Group 1: Hg, which is very volatile. Group 2: Pb, Zn, Cd, which are partially volatile. Group 3: Mn, which is hardly volatile. Se may be located between groups 1 and 2. Cr has properties of both group 1 and 3. In addition, the smaller diameter of fly ash, the more relative enrichment of trace elements (except Mn). The fly ash showed different adsorption mechanisms of trace elements and the volatilization of trace elements rises with furnace temperature. Relative enrichments of trace elements(except Mn and Cr) in fly ash are larger than that in bottom ash. Low oxygen content can not always improve the volatilization of trace elements. Pb is easier to form chloride than Cd during Coal combustion. Trace elements should be classified in accordance with factors.
Hoyoung Park - One of the best experts on this subject based on the ideXlab platform.
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numerical and experimental investigations on the gas temperature deviation in a large scale advanced low nox tangentially fired Pulverized Coal Boiler
Fuel, 2013Co-Authors: Hoyoung Park, Sehyun Baek, Dong Soo KangAbstract:Abstract This paper describes the numerical and experimental investigations of the gas temperature deviation in the crossover pass of a large scale, advanced low NOx, tangentially fired Pulverized Coal Boiler. Major attention was paid to the region of the final super-heater where the tube ruptures occasionally had been occurred due to the tube overheating. Computational Fluid Dynamics (CFD) simulation and measurements of gas temperature just in front of the final super-heater showed the gas temperature distribution was biased to the left, lower region of that heater. It was found that this deviation is originated from the residual swirl flow in the upper furnace. To alleviate the gas temperature deviation, the changes in yaw angles of over-fire air have been suggested and the field tests carried out to identify their effects on that deviation. The test showed it is quite effective method to reduce that deviation.
Fangqin Cheng - One of the best experts on this subject based on the ideXlab platform.
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numerical simulation and cold experimental research of a low nox combustion technology for Pulverized low volatile Coal
Applied Thermal Engineering, 2017Co-Authors: Jing Wang, Kailiang Zheng, Ravinder Singh, Baofeng Wang, Fangqin ChengAbstract:Abstract Large quantities of low-volatile Coal are utilized in power plants throughout China. With increasingly stringent environmental regulations, it is important to develop and deploy low-NOx combustion technologies for Pulverized Coal Boilers burning low-volatile Coal. The objective of this study was to investigate a novel decoupling combustion system for low-volatile Coal via experiments and computational fluid dynamics (CFD). The combustion system includes horizontal fuel-rich/lean low-NOx burners (LNB) and the associated air distribution system for a polygonal tangentially fired Boiler (PTFB). The effects of Coal particle diameter and Coal feeding rate on the gas/particle flow characteristics of the burner, and the cold state aerodynamic field of the PTFB were analyzed in detail. The structural design of the LNB results in advantageous gas/particle flow characteristics and the PTFB improved the distribution of the flow field. The CFD models and simulation results were validated by comparing with those of cold experiments data. The simulation results demonstrated that this low-NOx combustion technology enhances staged combustion at different scales, which can reduce NOx generation significantly. In the industrial application on a 300 MW Pulverized Coal Boiler, installation of the LNBs improved the stability of low-volatile Coal combustion and reduced NOx emissions significantly. These research findings provide valuable guidance to the design of low-NOx combustion system for Pulverized Coal Boilers using low volatile Coal.
