The Research Of Cfb Boiler Operation For Oxygen Enhanced Dried Lignite Combustion,
2011
Czestochowa University of Technology
The Research Of Cfb Boiler Operation For Oxygen Enhanced Dried Lignite Combustion, Wojciech Nowak, Waldemar Muskala, Jaroslaw Krzywanski, Tomasz Czakiert
10th International Conference on Circulating Fluidized Beds and Fluidization Technology - CFB-10
The paper presents the research of CFB boiler operation for oxygen-enhanced dried lignite combustion. The combustion in oxygen-enhanced conditions generally leads to reducing the emissions of CO and NOx and N2O due to reduced volume of flue gas. The maximum oxygen content for oxygen-enhanced combustion in O2/N2 conditions should not exceed 60%, however, the maximum drying extent of fuel should not be higher than 50% of the initial moisture content in an examined lignite.
Dem-Cfd Modeling Of A Bubbling Fluidized Bed And A Wurster Coater,
2011
Hamburg University of Technology
Dem-Cfd Modeling Of A Bubbling Fluidized Bed And A Wurster Coater, Lennart Fries, Sergiy Antonyuk, Stefan Heinrich, Stefan Palzer
10th International Conference on Circulating Fluidized Beds and Fluidization Technology - CFB-10
Coupled DEM-CFD simulations were performed to study the fluid and particle dynamics of a fluidized bed granulator on the micro-scale. In a first study, wetting of the particles is estimated based on the residence time distribution inside a conical spray zone. The effect of the geometry of the apparatus on the homogeneity of wetting is analyzed in order to understand the performance and specificity of different granulator configurations. For a small simulation system, heat and mass transfer laws were resolved to calculate the moisture content of the individual particles An effective modelling tool for design of a fluidized bed spray …
Circulating Fluidized Bed Combustion-Build-Up And Validation Of A Three-Dimensional Model,
2011
Metso Power Oy
Circulating Fluidized Bed Combustion-Build-Up And Validation Of A Three-Dimensional Model, Marko Palonen, David Pallarès, Anton Larsson, Filip Johnsson, Ville Ylä-Outinen, Jukka Laine
10th International Conference on Circulating Fluidized Beds and Fluidization Technology - CFB-10
This paper presents the validated simulation of a full-scale circulating fluidized bed boiler as obtained via a comprehensive three-dimensional CFB process model. The model is utilized in boiler design and scale-up as well as to study and optimize boiler performance. Feedstock characterization tests, which are also presented, are used to provide data for those parts of the process where up-to-date modeling is not fully reliable, thus enabling the model to provide accurate results.
Effect Of Temperature Field On The Coal Devolatilization In A Millisecond Downer Reactor,
2011
Tsinghua University, China
Effect Of Temperature Field On The Coal Devolatilization In A Millisecond Downer Reactor, Binhang Yan, Li Zhang, Yong Jin, Yi Cheng
10th International Conference on Circulating Fluidized Beds and Fluidization Technology - CFB-10
A comprehensive CFD-DPM model was established to describe coal pyrolysis in millisecond downer reactors under high temperatures. The model predictions revealed the fact that the reactor performance is dominated by the design of the temperature field to guarantee fast, sufficient heating of coal particles in milliseconds
Experimental Study On Reforming Activity And Oxygen Transfer Of Fe- Olivine In A Dual Circulating Fluidized Bed System,
2011
Vienna University of Technology
Experimental Study On Reforming Activity And Oxygen Transfer Of Fe- Olivine In A Dual Circulating Fluidized Bed System, Stefan Koppatz, Tobias Pröll, Christoph Pfeifer, Hermann Hofbauer
10th International Conference on Circulating Fluidized Beds and Fluidization Technology - CFB-10
Fe-olivine was investigated in a dual circulating fluidised bed reactor system with focus on hydrocarbon reforming activity and effects of oxygen transfer. H2, CO2, CH4 and 1-methylnaphthalene were fed as a surrogate gas mixture to the reforming part. Oxygen transport was developed by solids circulation. Tar decomposition was marginally affected by partial oxidation. The overall degree of tar decomposition was found to be in the range of 70 to 80%.
Effects Of Secondary Air Injection Upon The Fluidization Characteristics Of The Lower Stage In A Two-Stage, Variable-Area Fluidized Bed Riser,
2011
West Virginia University
Effects Of Secondary Air Injection Upon The Fluidization Characteristics Of The Lower Stage In A Two-Stage, Variable-Area Fluidized Bed Riser, Eric K. Johnson, Steven L. Rowan
10th International Conference on Circulating Fluidized Beds and Fluidization Technology - CFB-10
A transparent scale model of a two-stage fluidized bed coal dryer with a small diameter lower stage and a large diameter upper stage, separated by a conical transition zone with secondary air injection ports, has been constructed to study the effects of secondary air injection upon the fluidization characteristics of the lower riser stage. The superficial velocity of the lower stage of the riser was held constant within the turbulent fluidization regime while the superficial gas velocity in the upper riser stage was varied by changing the volumetric flow rates of air introduced between the upper and lower riser stages. …
Oxy-Combustion Of Different Coals In A Circulating Fluidized Bed,
2011
Sasol Technology, South Africa
Oxy-Combustion Of Different Coals In A Circulating Fluidized Bed, Adam Luckos, Monika Kosowska-Golachowska, Konrad Klos, Tomasz Musial
10th International Conference on Circulating Fluidized Beds and Fluidization Technology - CFB-10
Combustion of three Polish and one South African bituminous coal particles in air versus O2/CO2 mixtures with oxygen concentrations in the range from 21% to 60% vol. was conducted at temperature of 850°C in a 12 kW bench-scale CFB combustor. Combustion in air was proceeded at ~50˚C higher centre temperatures and was slightly shorter in time compared to combustion in O2/CO2 mixture with 21% vol. O2. Larger heat capacity of CO2 compared to that of N2 also retards the ignition of volatiles in O2/CO2 mixtures with 21% O2. However, when the concentration of oxygen in O2/CO2 mixtures is larger than …
Comparison Between Measurements And Numerical Simulation Of Particle Flow And Combustion A The Cfbc Plant Duisburg,
2011
aixprocess GmbH
Comparison Between Measurements And Numerical Simulation Of Particle Flow And Combustion A The Cfbc Plant Duisburg, M. Weng, J Plackmeyer
10th International Conference on Circulating Fluidized Beds and Fluidization Technology - CFB-10
The article presents the 3-dimensional numerical simulation of combustion and particle flow as an efficient engineering tool for analysis and optimization of fluidized bed combustion chambers. The comparison with measurements that were carried out within a European Research Project and with operational experience shows very good agreement and provides recommendations for future optimization.
Elutriation From Fluidized Beds: Comparison Between Experimental Measurements And 3d Simulation Results,
2011
CNRS; Federation de Recherche FERMAT, France
Elutriation From Fluidized Beds: Comparison Between Experimental Measurements And 3d Simulation Results, Renaud Ansart, Herve Neau, Olivier Simonin, Philippe Accart, Alain De Ryck
10th International Conference on Circulating Fluidized Beds and Fluidization Technology - CFB-10
This paper presents comparisons between experimental measurements and unsteady threedimensional numerical simulations performed by an unstructured parallelized CFD multiphase flow code of elutriation and transport of mono-dispersed glass beads type B and A/B in a fluidized bed. These comparisons show a satisfactory agreement between experimental measurements and numerical predictions. The numerical results also show a strong dependence on the mesh size, especially for fine particles. A model accounting for influences of mesoscales structures on overall bed hydrodynamics, which are not resolved by coarse mesh simulations, is applied. Results obtained with the model show improvements for the dense fluidized bed and …
Hydrodynamics Of A Cluster Descending At The Wall Of A Cfb Riser - Numerical Study,
2011
University of British Columbia
Hydrodynamics Of A Cluster Descending At The Wall Of A Cfb Riser - Numerical Study, John R. Grace, Subhashini Vashisth
10th International Conference on Circulating Fluidized Beds and Fluidization Technology - CFB-10
The incompressible hydrodynamics of a single parabolic cluster descending at the wall of a CFB riser was numerically simulated using a 2-D Eulerian-Granular model and a segregated time-dependent unsteady solver. Numerical predictions of the velocity of descent and the evolution of cluster shape are in reasonable agreement with experimental results available in the literature.
High Sulfur Lignite Fired Large Cfb Boilers-Design And Operating Experience,
2011
Bharat Heavy Electrical Limited
High Sulfur Lignite Fired Large Cfb Boilers-Design And Operating Experience, M. Lakshminarasimhan, B. Ravikumar, A. Lawrence, M. Muthukrishnan
10th International Conference on Circulating Fluidized Beds and Fluidization Technology - CFB-10
One of the measures of the prosperity of a nation is per capita consumption of electricity. In developing countries like India the gap between supply and demand is strongly increasing. The demand for all forms of energy is expected to increase substantially in the foreseeable future and is forecasted to double by 2020. Although coal would continue to be a major energy source in India due to its availability, lignite is fast emerging as an alternate source of fuel for electricity generation. In India the total lignite potential is 4177 million tonnes. The varieties found in India (Gujarat & Rajasthan …
Research On Heat Transfer Inside The Furnace Of Large Scale Cfb Boilers,
2011
Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Thermal Engineering, Tsinghua University
Research On Heat Transfer Inside The Furnace Of Large Scale Cfb Boilers, Ruiqing Zhang, Hairui Yang, Hai Zhang, Qing Liu, Junfu Lu, Yuxin Wu
10th International Conference on Circulating Fluidized Beds and Fluidization Technology - CFB-10
Field tests in one unit of 135MWe and two units of 300MWe commercial Circulating Fluidized bed (CFB) boilers (A&B) with different structures were carried out. The influence of operating conditions on the thermal boundary layer, local heat transfer coefficient and peripheral distribution of heat transfer coefficient were studied. It was found that, in the 135MWe and 300MWe-A CFB furnace, the thickness of the thermal boundary layer was almost constant, about 100mm, and independent of the height above the distributor and the boiler load. The local heat transfer coefficient increased with increasing load as well as the coal feeding rate and …
Co-Gasification Of Biomass And Coal In An 8mw Dual Fluidized Bed Steam Gasifier,
2011
Vienna University of Technology
Co-Gasification Of Biomass And Coal In An 8mw Dual Fluidized Bed Steam Gasifier, Christoph Pfeifer, Isabella Aigner, Hermann Hofbauer
10th International Conference on Circulating Fluidized Beds and Fluidization Technology - CFB-10
Gasification of biomass is an attractive technology for combined heat and power production. Co-gasification of biomass and coal was tested in an 8 MW dual fluidized bed steam gasifier with coal ratios up to 22% on an energy basis. Hydrogen levels in the producer gas increased with the addition of coal as well as ammonia, hydrogen sulfide and tars. Addition of coal to the system stabilized the process and improved gas quality.
Operating Experience And Latest Developments Of Alstom Power's 300 Mwe Class Cfb Boilers,
2011
Alstom Power R&D Execution
Operating Experience And Latest Developments Of Alstom Power's 300 Mwe Class Cfb Boilers, Iqbal Abdulally, Bruce Wilhelm, Christian Enault, Pierre Gauville
10th International Conference on Circulating Fluidized Beds and Fluidization Technology - CFB-10
Fuel flexibility combined with low emissions, particularly with high sulphur fuels, are the key drivers for installing a Circulating Fluidised Bed (CFB) Boiler. Taking into account the global drive for more efficient and clean combustion, and the development of CFB combustion and emission reduction technologies accordingly, worldwide applications for CFB Boilers are increasing. Accordingly, Alstom Power continues the evolutionary development of its CFB Boiler portfolio, based on the experience gained with operating units. This paper focuses on Alstom Power’s 300 MWe Class CFB Boiler products. East Kentucky Power Cooperative's (EKPC) Spurlock unit 4 is one of the large Alstom’s 300 …
Coal And Biomass Co-Gasification In A Circulating Fluidized Bed Reactor,
2011
Institute for Chemical Processing of Coal
Coal And Biomass Co-Gasification In A Circulating Fluidized Bed Reactor, Andrzej Czaplicki, Marek Sciazko
10th International Conference on Circulating Fluidized Beds and Fluidization Technology - CFB-10
Co-gasification tests of subbituminous coal with biomass were performed. A rape straw blended with coal was used in a mass ratios of coal/biomass of 25%, 50% and 75%. The gasification process was conducted in a circulating fluid bed reactor at atmospheric pressure with air and steam addition was applied to the reaction. The addition of biomass to coal resulted in a higher conversion to gas and increased the gas calorific value due to higher content of carbon oxide
Design And Operation Of Biomass Circulating Fluidized Bed Boiler With High Steam Parameter,
2011
Chinese Academy of Sciences
Design And Operation Of Biomass Circulating Fluidized Bed Boiler With High Steam Parameter, Li Shiyuan, Lu Qinggang, Teng Haipeng, Shaolin Bao, Dongyu Wang
10th International Conference on Circulating Fluidized Beds and Fluidization Technology - CFB-10
Two circulating fluidized bed(CFB) boilers with capacity of 12 MWe and 25 MWe, respectively, with biomass as fuel, adopting the basic technology independently developed by Institute of Engineering Thermophysics (IET), Chinese Academy of Sciences, have been in commercial operation since March 2010 in China. This paper focuses on the design principles, the design specifications and operating results of the two CFB boilers.
Commissioning Of A 0.8 Mwth Cfbc For Oxy-Fuel Combustion,
2011
CanmetENERGY
Commissioning Of A 0.8 Mwth Cfbc For Oxy-Fuel Combustion, L. Jia, D. Mccalden, Y. Tan, Y. Wu, I. He, R. Symmonds, E.J. Anthony
10th International Conference on Circulating Fluidized Beds and Fluidization Technology - CFB-10
Oxy-fuel fluidized bed combustion (FBC) is a new technology being developed for power production from carbonaceous fuels while producing a nearly pure steam of CO2 ready for sequestration or storage. Unlike oxy-fuel pulverized fuel combustion technology, oxy-fuel FBC offers the opportunity to use poor quality coals, hydrocarbon residues and a range of other materials including biomass. In Canada, pitches, tars and bottoms, in particular, are available in large quantities in western Canada, and this technology offers an opportunity to deal with many of these waste feedstocks in an environmentally benign manner. In addition, oxy-fuel circulating FBC (CFBC) can be fired …
Particle To Gas Heat Transfer In A Circulating Fluidized Bed Riser,
2011
Heriot-Watt University
Particle To Gas Heat Transfer In A Circulating Fluidized Bed Riser, Yassir Makkawi
10th International Conference on Circulating Fluidized Beds and Fluidization Technology - CFB-10
The main objective of this study was to measure the heat transfer from particle to gas in a dilute CFB riser ( 0.8 ) and to derive a predictive equation for the local particle-gas heat transfer coefficient. This coefficient was found to be a strong function of the particle velocity, concentration and length of the heat transfer section. Accordingly, a new correlation in terms of these parameters is proposed.
Study Of Recarbonation In Circulating Fluidized Bed Combustion,
2011
Metso Power Oy
Study Of Recarbonation In Circulating Fluidized Bed Combustion, Marko Palonen, Irina Hyyatiäinen, Anna Mahlamäki, Mikko Varonen
10th International Conference on Circulating Fluidized Beds and Fluidization Technology - CFB-10
Oxy-fuel circulating fluidized bed combustion (CFBC) can use calcium based sorbents, primarily limestone, for the in-situ capture of much of the sulfur dioxide in the fuel. Under oxy-fuel CFBC conditions, the CO2 content is usually high, and at high combustor temperatures sulfur capture can occur in two steps, calcination and then sulfation. The typical Ca utilization ratio in oxy-fuel CFBCs is less than half. When temperature is below the calcination temperature while remaining exposed to a high CO2 environment, recarbonation of unused CaO may occur. This reaction between calcium oxide and carbon dioxide has the potential to create serious operational …
Uop Fcc Innovations Developed Using Sophisticated Engineering Tools,
2011
UOP LLC, a Honeywell Company Des Plaines, Illinois, USA
Uop Fcc Innovations Developed Using Sophisticated Engineering Tools, Lisa Wolschlag, Keith Couch
10th International Conference on Circulating Fluidized Beds and Fluidization Technology - CFB-10
Fluid Catalytic Cracking (FCC) technology has been a part of the petroleum industry since the 1940’s. Yet, despite being a very mature technology, continued development is vital, especially as many refiners move their FCC operations from fuels production to higher value products. Advanced diagnostic and design tools are accelerating process developments and have resulted in several innovations. Through the development and commercialization of world record scale FCC units, technical discoveries have emerged, which have provided opportunities for improvements across all units, independent of size. Through the development and use of sophisticated engineering tools such as Computational Fluid Dynamic (CFD) modeling, …
