Download or read book NOx Formation During Pulverised Coal Combustion written by Ir. Riman Sipahutar and published by . This book was released on 1992 with total page 446 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Kinetics of NOx Formation During Early Stages of Pulverized Coal Combustion written by J. M. Kennedy and published by . This book was released on 1982 with total page 59 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book 23 European Symposium on Computer Aided Process Engineering written by Achim Wechsung and published by Elsevier Inc. Chapters. This book was released on 2013-06-10 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: A dynamic model of a coal fired boiler is proposed to predict the formation of NOx during plant operation. Since evaluation of the model at hand should only take few minutes, computationally expensive CFD simulations are not feasible. Instead, it is proposed to represent the boiler as a network of ideal reactors. Gas phase reactions are modeled using a detailed kinetic mechanism; additional consideration is necessary for the heterogeneous reactions on char particles. In the reported preliminary case studies, radiative heat transfer is not considered.

Download or read book Modeling and Simulation of SOx and NOx Reduction Processes in Pulverized Coal Furnaces written by and published by Cuvillier Verlag. This book was released on 2003-12-18 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT The current work briefly reviews the formation mechanisms and reduction approaches of the pollutants SOx and NOx in coal combustion and focuses on the simulation of the lower-cost in-furnace measures ƒ{ the dry additive process (DAP) for SOx reduction and the reburning as well as the advanced reburning (hybrid reburning/SNCR) techniques for NOx reduction. In addition, the influence of sulfur compounds on NOx formation is investigated. The major workings include: Simulation of the dry additive desulfurization process (DAP): Different models ƒ{ shrinking core model (SCM), pore model (PM) and grain model (GM) ƒ{ are implemented to describe the gas-particle reaction. Relevant processes such as the sintering of the additive, the self-retention by coal ash, the thermal equilibrium of the sulfation reaction are accounted for and modeled. A comprehensive model for the DAP with calcium based additives is subsequently established and integrated into a combustion CFD (computational fluid dynamics) code AIOLOS, in both Eulerian and Lagrangian schemes. The model is verified with experiments on a test reactor. Mechanism reduction and simulation of reburning/SNCR Processes: A method for reduction of kinetic mechanisms is introduced. A program tool is developed for automatic reduction of detailed reaction mechanisms. Reduced mechanisms for reburning and hybrid reburning/SNCR processes are developed and implemented into the CFD code. CFD-calculations with the reduced mechanisms are performed and compared with experimental measurements to comprehensively evaluate the simulation approach. It is shown that the detailed simulation is capable of modeling the complex reburning and SNCR processes with acceptable computing time and achieves reasonable results in wide parameter ranges. Study of the influence of sulfur compounds on NOx formation: The effect of SO2 on NOx formation is experimentally investigated and analysed with kinetic mechanisms. It is indicated that the presence of SO2 inhabits the NOx formation and reduce the NOx emissions in normal air-rich combustion. Under air-staging conditions, SO2 addition has no obvious influence on the final NOx emissions.

Download or read book A study of fuel NOx formation in pulverized coal combustion written by M. Sato and published by . This book was released on 1986 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Framework for a Robust Predictor of NOx Emissions from Pulverised Coal Combustion II Factors which Contribute to NOx Formation in PF Combustion written by R.D.C. Smith and published by . This book was released on 1997 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fundamentals of the Physical Chemistry of Pulverized Coal Combustion written by L. Lahaye and published by Springer Science & Business Media. This book was released on 1987-08-31 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of coal for the production of energy is certainly not a new area of research. Many research works were carried out to improve the efficiency of industrial and domestic facilities. In the sixties, however, because of the availability and low cost of petroleum, coal consumption decreased and the research effort in this area was minimum. Meanwhile, the situation has totally changed. Considering the reserves of oil and the instability ofregions where they are located, it is becoming absolutely necessary to develop other sources of energy.The major alternative to oil appears to be coal, at least for the near future. Indeed, the reserves known today represent several centuries of energy consumption.!t is therefore becoming urgent to develop efficient and non polluting technologies to produce energy from coal. The main possibilities are : · liquefaction · gasification · directed combustion. Research and development efforts on liquefaction have been considerably reduced because of high cost of technologies involved and poor prospects for the next two decades. Research works on gasification are progressing; it is a promising approach. However, direct combustion either in pulverized coal furnaces or in fluidized beds is the more promising way of expanding rapidly the utilization of coal. These techniques are already used in some facilities but many environmental problems remain, slowing down their development.

Download or read book Predictions of NOx Emissions in Pulverized Coal Combustion written by Niko Hachenberg and published by . This book was released on 2014 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this research work was to develop a transferable mathematically simple model which gives the possibility to make fast and easy predictions regarding the NOx emission behavior of a broad-spectrum of coals within a certain combustion environment. In this context, this thesis is a further step of a common ongoing investigation focused on predicting NOx emissions from self-sustaining, pulverized coal combustion in dry bottom firing systems. A comprehensive literature research focused on already published NOx prediction approaches from scientific publications based on fundamental quantitative relationships or empirical algorithms and statistical relationships was also carried out in this context. This research concentrated on three specific areas which were found to constitute a major gap in the knowledge of NOx formation in industrial full-scale applications: the fuel properties; the dependence of furnace geometry factors; and the specific operating conditions. The developed model shows a strong statistical significance with a coefficient of determination of 0.9876 and a standard error of 28 mg / m3 STPdry at 6 % O2 based on 142 observations coming from 28 utility boilers. Direct comparisons between model history and observations reported by other researchers have also shown very good conformities. For that background, this thesis form a good basis for identifying individual factors which contributes to system related NOx emissions in order to investigate how variations in the process parameters affect the emission level. Perhaps, as contribution to the understanding of NOx formation during coal combustion what is still an imperfectly understood phenomenon, or as basis for possible process optimization which might find application on pulverized coal-fired boilers to make the world a little bit more green.

Download or read book Framework for a Robust Predictor of NOx Emissions from Pulverised Coal Combustion written by R. D. C. Smith and published by . This book was released on 1997 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Feasibility and NOx Reduction Potential of Flameless Oxidation in Pulverised Coal Combustion written by Dragisa Ristic and published by Cuvillier Verlag. This book was released on 2012-10-30 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the 1990, the flameless oxidation technology has been successfully proven as low-NOx combustion technology for gaseous hydrocarbon fuels, and the recent application of this technology to solid fuels such as pulverised coal has also become an area of interest. The objective of this thesis is to evaluate the feasibility and the potential of the flameless oxidation technology in the pulverised coal combustion. Firstly, the experimental studies on pulverised coal flameless oxidation process are conducted at a bench-scale test facility (5 to 10 kWth). In the next step, a suitable burner design in a pilot scale of approximately 300 kWth is developed, built up and experimentally studied. Detailed exhaust gas and inflame measurements of the temperature and, main species are carried out in order to address the specific aspects of pulverised coal flameless oxidation. Furthermore, to indicate the relevant NOx reduction mechanisms in the pulverised coal flameless oxidation process. In contrast to the conventional pulverised coal combustion, which has luminous and aerodynamically stabilised flames, the flameless oxidation combustion process has been achieved without a clearly visible flame. In the pulverised coal flameless oxidation mode, intensive internal recirculation is enhanced by a high injection velocity of the combustion air, and thus dilutes the combustion zone and heats up the coal particles in the primary pyrolysis zone. Once the coal particles are rapidly heated up, the processes of pyrolysis and volatile matter release are facilitated. Consequently, local reducing zone is formed, devolatilisation is enhanced, ignition delay is suppressed, combustion stability is improved and NOx emissions are reduced remarkably. A high internal recirculation of the oxygen-lean hot combustion products into the primary pyrolysis zone promotes an early devolatilisation and a decrease in ignition delay, which are two important factors for NOx reduction processes. Hence, a valuable potential of pulverised coal flameless oxidation is in the improved homogeneous gas phase kinetics and an enhanced homogeneous NO reburning mechanism. Besides NO reduction in the homogeneous gas phase, it is indicated that the NO reduction on the char surface in the heterogeneous and homogeneous gas phases is important as well, i.e. char NO reduction reaction and catalytic reduction of NO by CO on the char surface, in the pulverised coal flameless oxidation. As an overall conclusion, the PC FLOXTM (Pulverised Coal Flameless Oxidation) burner technology generally is evaluated as a perspective technology to provide low cost low NOx burners for utility boilers. Moreover, the PC FLOXTM burner technology offers the possibility of a lower cost alternative to the current approach of utilising SCR to enable power plants to meet current and future specific requirements on NOx emissions. However, despite all the advantages of this technology, it has been recognised that there are considerable technical challenges to the implementation of PC FLOXTM burners in utility boilers. High pressure loss in the main combustion air supply, boiler and burner design, arrangement of burners, start-up and shutdown procedures, etc. all require significant further work in order to bring the PC FLOXTM burner technology closer to the utility scale boilers.

Download or read book Combustion of Pulverised Coal in a Mixture of Oxygen and Recycled Flue Gas written by Dobrin Toporov and published by Elsevier. This book was released on 2014-05-30 with total page 199 pages. Available in PDF, EPUB and Kindle. Book excerpt: Combustion of Pulverised Coal in a Mixture of Oxygen and Recycled Flue Gas focuses on a niche technology, combustion of coal in an oxygen rich environment, which is one approach to obtaining 'clean coal,' by making it easier to capture carbon that is released in the combustion process. Toporov's book breaks ground on covering the key fundamentals of oxycoal technologies, which have not yet been covered in this depth. Combustion of Pulverised Coal in a Mixture of Oxygen and Recycled Flue Gas summarizes the main results from a pioneering work on experimental and numerical investigations of oxyfuel technologies. It provides the theoretical background of the process, the problems to be faced, and the technical solutions that were achieved during these investigations. - Summarizes results from investigations of oxyfuel technologies performed at Aachen University, Germany - Provides theoretical background, as well as the primary problems of these technologies and how they can be solved

Download or read book Combustion and Gasification of Coal written by A. Williams and published by Routledge. This book was released on 2018-12-19 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt: Incuding an overview of two of the most common uses of coal: combustion and gasification. First, it outlines problems and possible solutions, and then the nature of coal is described. The book goes on to describe the technical aspects of combustion of pulverized coal and the combustion mechanism of coal in fixed, moving, and fluidized beds. Industrial coal combustion applications are then outlined, together with other combustion applications, including co-firing, coal-water, slurries, and briquettes. Finally, gasification of coal, a possible major clean coal technology of the future, is discussed.

Download or read book NOx in Pulverised Coal Combustion written by Stuart C. Mitchell and published by . This book was released on 1998-01-01 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Formation of NOx in Staged Combustion of Pulverized Coal written by Joannes Wan Nan Lee and published by . This book was released on 1979 with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book How Coal Properties Influence Emissions written by Robert M. Davidson and published by . This book was released on 2000 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Pollutant control through staged combustion of pulverized coal written by J. O. L. Wendt and published by . This book was released on 1977 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Clean Coal and Sustainable Energy written by Junfu Lyu and published by Springer Nature. This book was released on 2021-09-29 with total page 1091 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book gathers the proceedings of the 9th International Symposium on Coal Combustion, held in Qingdao, China in July 2019. It provides the latest research results on techniques for pulverized coal combustion and fluidized bed combustion, low-carbon energy and emission controls, and industrial applications. Highlighting research areas that are of great importance in promoting collaboration between related subjects and the technical development of coal-related fields, the book offers a valuable reference guide for researchers and engineers alike.