The Experts below are selected from a list of 111 Experts worldwide ranked by ideXlab platform
Dragan Tucakovic - One of the best experts on this subject based on the ideXlab platform.
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numerical modeling of in Furnace sulfur removal by Sorbent Injection during pulverized lignite combustion
International Journal of Heat and Mass Transfer, 2019Co-Authors: Ivan Tomanovic, Aleksandar Milicevic, Nenad Crnomarkovic, Srdjan Belosevic, Dragan TucakovicAbstract:Abstract Results of the study on SO2 reduction in a utility boiler Furnace by means of Furnace Sorbent Injection are presented in this paper with analysis of major influential parameters. The Ca-based Sorbent Injection process in pulverized lignite fired boiler Furnace with tangentially arranged burners is simulated. In simulations Sorbent particles are distributed among the burner tiers, where they are injected together with coal, and also through Sorbent Injection ports located above the burners. The Sorbent reactions model was adapted to be efficiently implemented in the code for CFD simulations of complex processes considering both the calculation time and the results accuracy. The Sorbent particles reaction model was simplified with several assumptions to allow for faster calculations and significantly reduce simulation time without loss in calculation precision during the particle tracking in boiler Furnace. Two phase gas-particle flow is modeled, with coal and Sorbent particles reactions and interactions with gaseous phase. Test-cases based on fuels with different composition and combustion organization were simulated in details, and results showed that significant increase in reduction of SO2 at Furnace exit could be achieved by proper Sorbent Injection. The Sorbent Injection locations were analyzed with special care to enable maximum SO2 capture in the case-study Furnace under investigated conditions. Most of the test-cases with low SO2 capture had one or more of the following problems: intensive particle sintering, low local temperatures (leading to low calcination rates), or bad particles distribution. Significant SO2 retention was possible when the process was organized in such a way that particles were exposed to optimal temperature range, and injected in the Furnace zones with high SO2 concentration simultaneously. It was shown that better results can be achieved by Injection of Sorbent through multiple burner tiers, with SO2 emission reduction efficiency around 60% at the Furnace exit in several well optimized test-cases.
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NUMERICAL TRACKING OF Sorbent PARTICLES AND DISTRIBUTION DURING GAS DESULFURIZATION IN PULVERIZED COAL-FIRED Furnace
Thermal Science, 2017Co-Authors: Ivan Tomanovic, Srđan V. Belošević, Aleksandar Milicevic, Nenad Crnomarkovic, Dragan TucakovicAbstract:Furnace Sorbent Injection for sulfur removal from flue gas presents a challenge, as the proper process optimization is of crucial importance in order to obtain both high sulfur removal rates and good Sorbent utilization. In the simulations a two-phase gas-particle flow is considered. Pulverized coal and calcium-based Sorbent particles motion is simulated inside of the boiler Furnace. It is important to determine trajectories of particles in the Furnace, in order to monitor the particles heat and concentration history. A two-way coupling of the phases is considered – influence of the gas phase on the particles, and vice versa. Particle– to–particle collisions are neglected. Mutual influence of gas and dispersed phase is modeled by corresponding terms in the transport equations for gas phase and the equations describing the particles turbulent dispersion. Gas phase is modeled in Eulerian field, while the particles are tracked in Lagrangian field. Turbulence is modelled by the standard k-e model, with additional terms for turbulence modulation. Distribution, dispersion and residence time of Sorbent particles in the Furnace have a considerable influence on the desulfurization process. It was shown that, by proper organization of process, significant improvement considering emission reduction can be achieved.
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Numerical study of pulverized coal-fired utility boiler over a wide range of operating conditions for in-Furnace SO2/NOx reduction
Applied Thermal Engineering, 2016Co-Authors: Srdjan Belosevic, Ivan Tomanovic, Aleksandar Milicevic, Nenad Crnomarkovic, Dragan TucakovicAbstract:Abstract Important tasks during pulverized coal-fired utility boiler exploitation are efficient utilization of variable quality fuels, operation in a wide range of loads and emission reduction of pollutants, like oxides of nitrogen and sulfur. Combustion process modifications for NOx control and the Furnace Sorbent Injection for SO2 control are cost-effective clean coal technologies. For optimization of boiler operation mathematical prediction is regularly used and the need for modeling is most apparent in complex flows, such as turbulent reactive flows in coal-fired Furnaces. Simulation of processes in a utility boiler pulverized lignite-fired Furnace was performed by an in-house developed numerical code. The code is a promising numerical tool to be used also by engineering staff dealing with the process analysis in boiler units. A broad range of operating conditions was examined, such as different boiler loads, fuel and preheated air distribution over the burners and the burner tiers, grinding fineness of coal, cold air ingress and recirculation of flue gases from the boiler exit. Ash deposit on the screen walls, affecting the heat exchange inside the Furnace, was considered as well. Simulations suggested optimal combustion modifications providing NOx emission reduction, with the flame geometry improvement, as well. SO2 reduction by Injection of pulverized Ca-based Sorbents into the Furnace was also analyzed. Models of the Sorbent particle calcination, sintering and sulfation reactions were optimized and implemented within the numerical code. Numerical experiments considered different operation parameters, such as Ca/S molar ratio, Sorbent particle size and dispersion, local gas temperature in different Injection zones and the particle residence time. A proper distribution of finely ground Sorbent particles could be expected to provide an efficient absorption of SO2. With respect to the boiler thermal calculations, the facility should be controlled within narrow limits of operation parameters due to often contradictory requirements with respect to emission reduction and the boiler unit efficiency with safe operation of superheaters. A number of influencing parameters require such a complex approach to evaluate alternative solutions and enable efficient, low emission and flexible operation of power plant boiler units.
Ivan Tomanovic - One of the best experts on this subject based on the ideXlab platform.
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numerical modeling of in Furnace sulfur removal by Sorbent Injection during pulverized lignite combustion
International Journal of Heat and Mass Transfer, 2019Co-Authors: Ivan Tomanovic, Aleksandar Milicevic, Nenad Crnomarkovic, Srdjan Belosevic, Dragan TucakovicAbstract:Abstract Results of the study on SO2 reduction in a utility boiler Furnace by means of Furnace Sorbent Injection are presented in this paper with analysis of major influential parameters. The Ca-based Sorbent Injection process in pulverized lignite fired boiler Furnace with tangentially arranged burners is simulated. In simulations Sorbent particles are distributed among the burner tiers, where they are injected together with coal, and also through Sorbent Injection ports located above the burners. The Sorbent reactions model was adapted to be efficiently implemented in the code for CFD simulations of complex processes considering both the calculation time and the results accuracy. The Sorbent particles reaction model was simplified with several assumptions to allow for faster calculations and significantly reduce simulation time without loss in calculation precision during the particle tracking in boiler Furnace. Two phase gas-particle flow is modeled, with coal and Sorbent particles reactions and interactions with gaseous phase. Test-cases based on fuels with different composition and combustion organization were simulated in details, and results showed that significant increase in reduction of SO2 at Furnace exit could be achieved by proper Sorbent Injection. The Sorbent Injection locations were analyzed with special care to enable maximum SO2 capture in the case-study Furnace under investigated conditions. Most of the test-cases with low SO2 capture had one or more of the following problems: intensive particle sintering, low local temperatures (leading to low calcination rates), or bad particles distribution. Significant SO2 retention was possible when the process was organized in such a way that particles were exposed to optimal temperature range, and injected in the Furnace zones with high SO2 concentration simultaneously. It was shown that better results can be achieved by Injection of Sorbent through multiple burner tiers, with SO2 emission reduction efficiency around 60% at the Furnace exit in several well optimized test-cases.
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NUMERICAL TRACKING OF Sorbent PARTICLES AND DISTRIBUTION DURING GAS DESULFURIZATION IN PULVERIZED COAL-FIRED Furnace
Thermal Science, 2017Co-Authors: Ivan Tomanovic, Srđan V. Belošević, Aleksandar Milicevic, Nenad Crnomarkovic, Dragan TucakovicAbstract:Furnace Sorbent Injection for sulfur removal from flue gas presents a challenge, as the proper process optimization is of crucial importance in order to obtain both high sulfur removal rates and good Sorbent utilization. In the simulations a two-phase gas-particle flow is considered. Pulverized coal and calcium-based Sorbent particles motion is simulated inside of the boiler Furnace. It is important to determine trajectories of particles in the Furnace, in order to monitor the particles heat and concentration history. A two-way coupling of the phases is considered – influence of the gas phase on the particles, and vice versa. Particle– to–particle collisions are neglected. Mutual influence of gas and dispersed phase is modeled by corresponding terms in the transport equations for gas phase and the equations describing the particles turbulent dispersion. Gas phase is modeled in Eulerian field, while the particles are tracked in Lagrangian field. Turbulence is modelled by the standard k-e model, with additional terms for turbulence modulation. Distribution, dispersion and residence time of Sorbent particles in the Furnace have a considerable influence on the desulfurization process. It was shown that, by proper organization of process, significant improvement considering emission reduction can be achieved.
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Numerical study of pulverized coal-fired utility boiler over a wide range of operating conditions for in-Furnace SO2/NOx reduction
Applied Thermal Engineering, 2016Co-Authors: Srdjan Belosevic, Ivan Tomanovic, Aleksandar Milicevic, Nenad Crnomarkovic, Dragan TucakovicAbstract:Abstract Important tasks during pulverized coal-fired utility boiler exploitation are efficient utilization of variable quality fuels, operation in a wide range of loads and emission reduction of pollutants, like oxides of nitrogen and sulfur. Combustion process modifications for NOx control and the Furnace Sorbent Injection for SO2 control are cost-effective clean coal technologies. For optimization of boiler operation mathematical prediction is regularly used and the need for modeling is most apparent in complex flows, such as turbulent reactive flows in coal-fired Furnaces. Simulation of processes in a utility boiler pulverized lignite-fired Furnace was performed by an in-house developed numerical code. The code is a promising numerical tool to be used also by engineering staff dealing with the process analysis in boiler units. A broad range of operating conditions was examined, such as different boiler loads, fuel and preheated air distribution over the burners and the burner tiers, grinding fineness of coal, cold air ingress and recirculation of flue gases from the boiler exit. Ash deposit on the screen walls, affecting the heat exchange inside the Furnace, was considered as well. Simulations suggested optimal combustion modifications providing NOx emission reduction, with the flame geometry improvement, as well. SO2 reduction by Injection of pulverized Ca-based Sorbents into the Furnace was also analyzed. Models of the Sorbent particle calcination, sintering and sulfation reactions were optimized and implemented within the numerical code. Numerical experiments considered different operation parameters, such as Ca/S molar ratio, Sorbent particle size and dispersion, local gas temperature in different Injection zones and the particle residence time. A proper distribution of finely ground Sorbent particles could be expected to provide an efficient absorption of SO2. With respect to the boiler thermal calculations, the facility should be controlled within narrow limits of operation parameters due to often contradictory requirements with respect to emission reduction and the boiler unit efficiency with safe operation of superheaters. A number of influencing parameters require such a complex approach to evaluate alternative solutions and enable efficient, low emission and flexible operation of power plant boiler units.
Lewis Benson - One of the best experts on this subject based on the ideXlab platform.
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computational modeling of Furnace Sorbent Injection for so2 removal from coal fired utility boilers
Fuel Processing Technology, 2011Co-Authors: Brian S Higgins, Lewis BensonAbstract:Abstract Furnace Sorbent Injection (FSI) is used to remove SO 2 formed during coal combustion by injecting Sorbent into the high temperature zone of a Furnace above the fireball. FSI is cost effective for older coal-fired boilers, especially when space or capital budgets are limited. To optimize the design and performance of FSI, an SO 2 /Sorbent modeling scheme that simultaneously considers calcination (or dehydration), sintering, and sulfation has been developed and implemented. It is coupled with a three-dimensional combustion model based on computational fluid dynamics to determine the most desirable locations for Sorbent Injection and to optimize the amount of Sorbent needed to achieve a targeted SO 2 removal efficiency. A sensitivity analysis was conducted to determine the effect of flue gas temperature, particle diameter, and SO 2 concentration on the extent of sulfation. This SO 2 /Sorbent sub-model was applied to a 126-MW front-wall fired boiler firing eastern bituminous coal. The SO 2 removal efficiencies predicted by the model agreed well with those measured in the field. The modeling results indicated that Sorbent injected directly into the Furnace through boosted over-fired air ports is more effective at removing SO 2 , due to longer residence time and better mixing, relative to ports higher in the Furnace with poor mixing. This modeling approach is optimized for full-Furnace application to facilitate the design process.
Srdjan Belosevic - One of the best experts on this subject based on the ideXlab platform.
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numerical modeling of in Furnace sulfur removal by Sorbent Injection during pulverized lignite combustion
International Journal of Heat and Mass Transfer, 2019Co-Authors: Ivan Tomanovic, Aleksandar Milicevic, Nenad Crnomarkovic, Srdjan Belosevic, Dragan TucakovicAbstract:Abstract Results of the study on SO2 reduction in a utility boiler Furnace by means of Furnace Sorbent Injection are presented in this paper with analysis of major influential parameters. The Ca-based Sorbent Injection process in pulverized lignite fired boiler Furnace with tangentially arranged burners is simulated. In simulations Sorbent particles are distributed among the burner tiers, where they are injected together with coal, and also through Sorbent Injection ports located above the burners. The Sorbent reactions model was adapted to be efficiently implemented in the code for CFD simulations of complex processes considering both the calculation time and the results accuracy. The Sorbent particles reaction model was simplified with several assumptions to allow for faster calculations and significantly reduce simulation time without loss in calculation precision during the particle tracking in boiler Furnace. Two phase gas-particle flow is modeled, with coal and Sorbent particles reactions and interactions with gaseous phase. Test-cases based on fuels with different composition and combustion organization were simulated in details, and results showed that significant increase in reduction of SO2 at Furnace exit could be achieved by proper Sorbent Injection. The Sorbent Injection locations were analyzed with special care to enable maximum SO2 capture in the case-study Furnace under investigated conditions. Most of the test-cases with low SO2 capture had one or more of the following problems: intensive particle sintering, low local temperatures (leading to low calcination rates), or bad particles distribution. Significant SO2 retention was possible when the process was organized in such a way that particles were exposed to optimal temperature range, and injected in the Furnace zones with high SO2 concentration simultaneously. It was shown that better results can be achieved by Injection of Sorbent through multiple burner tiers, with SO2 emission reduction efficiency around 60% at the Furnace exit in several well optimized test-cases.
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Numerical study of pulverized coal-fired utility boiler over a wide range of operating conditions for in-Furnace SO2/NOx reduction
Applied Thermal Engineering, 2016Co-Authors: Srdjan Belosevic, Ivan Tomanovic, Aleksandar Milicevic, Nenad Crnomarkovic, Dragan TucakovicAbstract:Abstract Important tasks during pulverized coal-fired utility boiler exploitation are efficient utilization of variable quality fuels, operation in a wide range of loads and emission reduction of pollutants, like oxides of nitrogen and sulfur. Combustion process modifications for NOx control and the Furnace Sorbent Injection for SO2 control are cost-effective clean coal technologies. For optimization of boiler operation mathematical prediction is regularly used and the need for modeling is most apparent in complex flows, such as turbulent reactive flows in coal-fired Furnaces. Simulation of processes in a utility boiler pulverized lignite-fired Furnace was performed by an in-house developed numerical code. The code is a promising numerical tool to be used also by engineering staff dealing with the process analysis in boiler units. A broad range of operating conditions was examined, such as different boiler loads, fuel and preheated air distribution over the burners and the burner tiers, grinding fineness of coal, cold air ingress and recirculation of flue gases from the boiler exit. Ash deposit on the screen walls, affecting the heat exchange inside the Furnace, was considered as well. Simulations suggested optimal combustion modifications providing NOx emission reduction, with the flame geometry improvement, as well. SO2 reduction by Injection of pulverized Ca-based Sorbents into the Furnace was also analyzed. Models of the Sorbent particle calcination, sintering and sulfation reactions were optimized and implemented within the numerical code. Numerical experiments considered different operation parameters, such as Ca/S molar ratio, Sorbent particle size and dispersion, local gas temperature in different Injection zones and the particle residence time. A proper distribution of finely ground Sorbent particles could be expected to provide an efficient absorption of SO2. With respect to the boiler thermal calculations, the facility should be controlled within narrow limits of operation parameters due to often contradictory requirements with respect to emission reduction and the boiler unit efficiency with safe operation of superheaters. A number of influencing parameters require such a complex approach to evaluate alternative solutions and enable efficient, low emission and flexible operation of power plant boiler units.
Nenad Crnomarkovic - One of the best experts on this subject based on the ideXlab platform.
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numerical modeling of in Furnace sulfur removal by Sorbent Injection during pulverized lignite combustion
International Journal of Heat and Mass Transfer, 2019Co-Authors: Ivan Tomanovic, Aleksandar Milicevic, Nenad Crnomarkovic, Srdjan Belosevic, Dragan TucakovicAbstract:Abstract Results of the study on SO2 reduction in a utility boiler Furnace by means of Furnace Sorbent Injection are presented in this paper with analysis of major influential parameters. The Ca-based Sorbent Injection process in pulverized lignite fired boiler Furnace with tangentially arranged burners is simulated. In simulations Sorbent particles are distributed among the burner tiers, where they are injected together with coal, and also through Sorbent Injection ports located above the burners. The Sorbent reactions model was adapted to be efficiently implemented in the code for CFD simulations of complex processes considering both the calculation time and the results accuracy. The Sorbent particles reaction model was simplified with several assumptions to allow for faster calculations and significantly reduce simulation time without loss in calculation precision during the particle tracking in boiler Furnace. Two phase gas-particle flow is modeled, with coal and Sorbent particles reactions and interactions with gaseous phase. Test-cases based on fuels with different composition and combustion organization were simulated in details, and results showed that significant increase in reduction of SO2 at Furnace exit could be achieved by proper Sorbent Injection. The Sorbent Injection locations were analyzed with special care to enable maximum SO2 capture in the case-study Furnace under investigated conditions. Most of the test-cases with low SO2 capture had one or more of the following problems: intensive particle sintering, low local temperatures (leading to low calcination rates), or bad particles distribution. Significant SO2 retention was possible when the process was organized in such a way that particles were exposed to optimal temperature range, and injected in the Furnace zones with high SO2 concentration simultaneously. It was shown that better results can be achieved by Injection of Sorbent through multiple burner tiers, with SO2 emission reduction efficiency around 60% at the Furnace exit in several well optimized test-cases.
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NUMERICAL TRACKING OF Sorbent PARTICLES AND DISTRIBUTION DURING GAS DESULFURIZATION IN PULVERIZED COAL-FIRED Furnace
Thermal Science, 2017Co-Authors: Ivan Tomanovic, Srđan V. Belošević, Aleksandar Milicevic, Nenad Crnomarkovic, Dragan TucakovicAbstract:Furnace Sorbent Injection for sulfur removal from flue gas presents a challenge, as the proper process optimization is of crucial importance in order to obtain both high sulfur removal rates and good Sorbent utilization. In the simulations a two-phase gas-particle flow is considered. Pulverized coal and calcium-based Sorbent particles motion is simulated inside of the boiler Furnace. It is important to determine trajectories of particles in the Furnace, in order to monitor the particles heat and concentration history. A two-way coupling of the phases is considered – influence of the gas phase on the particles, and vice versa. Particle– to–particle collisions are neglected. Mutual influence of gas and dispersed phase is modeled by corresponding terms in the transport equations for gas phase and the equations describing the particles turbulent dispersion. Gas phase is modeled in Eulerian field, while the particles are tracked in Lagrangian field. Turbulence is modelled by the standard k-e model, with additional terms for turbulence modulation. Distribution, dispersion and residence time of Sorbent particles in the Furnace have a considerable influence on the desulfurization process. It was shown that, by proper organization of process, significant improvement considering emission reduction can be achieved.
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Numerical study of pulverized coal-fired utility boiler over a wide range of operating conditions for in-Furnace SO2/NOx reduction
Applied Thermal Engineering, 2016Co-Authors: Srdjan Belosevic, Ivan Tomanovic, Aleksandar Milicevic, Nenad Crnomarkovic, Dragan TucakovicAbstract:Abstract Important tasks during pulverized coal-fired utility boiler exploitation are efficient utilization of variable quality fuels, operation in a wide range of loads and emission reduction of pollutants, like oxides of nitrogen and sulfur. Combustion process modifications for NOx control and the Furnace Sorbent Injection for SO2 control are cost-effective clean coal technologies. For optimization of boiler operation mathematical prediction is regularly used and the need for modeling is most apparent in complex flows, such as turbulent reactive flows in coal-fired Furnaces. Simulation of processes in a utility boiler pulverized lignite-fired Furnace was performed by an in-house developed numerical code. The code is a promising numerical tool to be used also by engineering staff dealing with the process analysis in boiler units. A broad range of operating conditions was examined, such as different boiler loads, fuel and preheated air distribution over the burners and the burner tiers, grinding fineness of coal, cold air ingress and recirculation of flue gases from the boiler exit. Ash deposit on the screen walls, affecting the heat exchange inside the Furnace, was considered as well. Simulations suggested optimal combustion modifications providing NOx emission reduction, with the flame geometry improvement, as well. SO2 reduction by Injection of pulverized Ca-based Sorbents into the Furnace was also analyzed. Models of the Sorbent particle calcination, sintering and sulfation reactions were optimized and implemented within the numerical code. Numerical experiments considered different operation parameters, such as Ca/S molar ratio, Sorbent particle size and dispersion, local gas temperature in different Injection zones and the particle residence time. A proper distribution of finely ground Sorbent particles could be expected to provide an efficient absorption of SO2. With respect to the boiler thermal calculations, the facility should be controlled within narrow limits of operation parameters due to often contradictory requirements with respect to emission reduction and the boiler unit efficiency with safe operation of superheaters. A number of influencing parameters require such a complex approach to evaluate alternative solutions and enable efficient, low emission and flexible operation of power plant boiler units.
