Download or read book Pilot Scale Demonstration of ALTA for NOx Control in Pulverized Coal Fired Boilers written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes computational fluid dynamics (CFD) modeling and pilot-scale testing conducted to demonstrate the ability of the Advanced Layered Technology Approach (ALTA) to reduce NO(subscript x) emissions in a pulverized coal (PC) boiler. Testing specifically focused on characterizing NO(subscript x) behavior with deep burner staging combined with Rich Reagent Injection (RRI). Tests were performed in a 4 MBtu/hr pilot-scale furnace at the University of Utah. Reaction Engineering International (REI) led the project team which included the University of Utah and Combustion Components Associates (CCA). Deep burner staging and RRI, combined with selective non-catalytic reduction (SNCR), make up the Advanced Layered Technology Approach (ALTA) for NO(subscript x) reduction. The application of ALTA in a PC environment requires homogenization and rapid reaction of post-burner combustion gases and has not been successfully demonstrated in the past. Operation of the existing low-NO(subscript x) burner and design and operation of an application specific ALTA burner was guided by CFD modeling conducted by REI. Parametric pilot-scale testing proved the chemistry of RRI in a PC environment with a NOx reduction of 79% at long residence times and high baseline NOx rate. At representative particle residence times, typical operation of the dual-register low-NO(subscript x) burner provided an environment that was unsuitable for NO(subscript x) reduction by RRI, showing no NOx reduction. With RRI, the ALTA burner was able to produce NO(subscript x) emissions 20% lower than the low-NO(subscript x) burner, 76 ppmv vs. 94 ppmv, at a burner stoichiometric ratio (BSR) of 0.7 and a normalized stoichiometric ratio (NSR) of 2.0. CFD modeling was used to investigate the application of RRI for NO(subscript x) control on a 180 MW{sub e} wall-fired, PC boiler. A NO(subscript x) reduction of 37% from baseline (normal operation) was predicted using ALTA burners with RRI to produce a NO(subscript x) emission rate of 0.185 lb/MBtu at the horizontal nose of the boiler. When combined with SNCR, a NO(subscript x) emission rate of 0.12-0.14 lb/MBtu can be expected when implementing a full ALTA system on this unit. Cost effectiveness of the full ALTA system was estimated at $2,152/ton NO(subscript x) removed; this was less than 75% of the cost estimated for an SCR system on a unit of this size.
Download or read book PARTICULATE CHARACTERIZATION AND ULTRA LOW NOx BURNER FOR THE CONTROL OF NO sub X AND PM sub 2 5 FOR COAL FIRED BOILERS written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In response to the serious challenge facing coal-fired electric utilities with regards to curbing their NO[sub x] and fine particulate emissions, Babcock and Wilcox and McDermott Technology, Inc. conducted a project entitled, ''Particulate Characterization and Ultra Low-NO[sub x] Burner for the Control of NO[sub x] and PM[sub 2.5] for Coal Fired Boilers.'' The project included pilot-scale demonstration and characterization of technologies for removal of NO[sub x] and primary PM[sub 2.5] emissions. Burner development and PM[sub 2.5] characterization efforts were based on utilizing innovative concepts in combination with sound scientific and fundamental engineering principles and a state-of-the-art test facility. Approximately 1540 metric tonnes (1700 tons) of high-volatile Ohio bituminous coal were fired. Particulate sampling for PM[sub 2.5] emissions characterization was conducted in conjunction with burner testing. Based on modeling recommendations, a prototype ultra low-NO[sub x] burner was fabricated and tested at 100 million Btu/hr in the Babcock and Wilcox Clean Environment Development Facility. Firing the unstaged burner with a high-volatile bituminous Pittsburgh 8 coal at 100 million Btu/hr and 17% excess air achieved a NO[sub x] goal of 0.20 lb NO[sub 2]/million Btu with a fly ash loss on ignition (LOI) of 3.19% and burner pressure drop of 4.7 in H[sub 2]O for staged combustion. With the burner stoichiometry set at 0.88 and the overall combustion stoichiometry at 1.17, average NO[sub x] and LOI values were 0.14 lb NO[sub 2]/million Btu and 4.64% respectively. The burner was also tested with a high-volatile Mahoning 7 coal. Based on the results of this work, commercial demonstration is being pursued. Size classified fly ash samples representative of commercial low-NO[sub x] and ultra low-NO[sub x] combustion of Pittsburgh 8 coal were collected at the inlet and outlet of an ESP. The mass of size classified fly ash at the ESP outlet was sufficient to evaluate the particle size distribution, but was of insufficient size to permit reliable chemical analysis. The size classified fly ash from the inlet of the ESP was used for detailed chemical analyses. Chemical analyses of the fly ash samples from the ESP outlet using a high volume sampler were performed for comparison to the size classified results at the inlet. For all test conditions the particulate removal efficiency of the ESP exceeded 99.3% and emissions were less than the NSPS limits of[approx]48 mg/dscm. With constant combustion conditions, the removal efficiency of the ESP increased as the ESP voltage and Specific Collection Area (SCA) increased. The associated decrease in particle emissions occurred in size fractions both larger and smaller than 2.5 microns. For constant ESP voltage and SCA, the removal efficiency for the ultra low-NO[sub x] combustion ash (99.4-99.6%) was only slightly less than for the low-NO[sub x] combustion ash (99.7%). The decrease in removal efficiency was accompanied by a decrease in ESP current. The emission of PM[sub 2.5] from the ESP did not change significantly as a result of the change in combustion conditions. Most of the increase in emissions was in the size fraction greater than 2.5 microns, indicating particle re-entrainment. These results may be specific to the coal tested in this program. In general, the concentration of inorganic elements and trace species in the fly ash at the ESP inlet was dependent on the particle size fraction. The smallest particles tended to have higher concentrations of inorganic elements/trace species than larger particles. The concentration of most elements by particle size range was independent of combustion condition and the concentration of soluble ions in the fly ash showed little change with combustion condition when evaluated on a carbon free basis.
Download or read book PARTICULATE CHARACTERIZATION AND ULTRA LOW NOx BURNER FOR THE CONTROL OF NOx AND PM sub 2 5 FOR COAL FIRED BOILERS written by and published by . This book was released on 2001 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt: In response to the serious challenge facing coal-fired electric utilities with regards to curbing their NOx and fine particulate emissions, Babcock and Wilcox and McDermott Technology, Inc. conducted a project entitled, ''Particulate Characterization and Ultra Low-NOx Burner for the Control of NOx and PM{sub 2.5} for Coal Fired Boilers.'' The project included pilot-scale demonstration and characterization of technologies for removal of NOx and primary PM{sub 2.5} emissions. Burner development and PM{sub 2.5} characterization efforts were based on utilizing innovative concepts in combination with sound scientific and fundamental engineering principles and a state-of-the-art test facility. Approximately 1540 metric tonnes (1700 tons) of high-volatile Ohio bituminous coal were fired. Particulate sampling for PM{sub 2.5} emissions characterization was conducted in conjunction with burner testing. Based on modeling recommendations, a prototype ultra low-NOx burner was fabricated and tested at 100 million Btu/hr in the Babcock and Wilcox Clean Environment Development Facility. Firing the unstaged burner with a high-volatile bituminous Pittsburgh 8 coal at 100 million Btu/hr and 17% excess air achieved a NOx goal of 0.20 lb NO2/million Btu with a fly ash loss on ignition (LOI) of 3.19% and burner pressure drop of 4.7 in H2O for staged combustion. With the burner stoichiometry set at 0.88 and the overall combustion stoichiometry at 1.17, average NOx and LOI values were 0.14 lb NO2/million Btu and 4.64% respectively. The burner was also tested with a high-volatile Mahoning 7 coal. Based on the results of this work, commercial demonstration is being pursued. Size classified fly ash samples representative of commercial low-NOx and ultra low-NOx combustion of Pittsburgh 8 coal were collected at the inlet and outlet of an ESP. The mass of size classified fly ash at the ESP outlet was sufficient to evaluate the particle size distribution, but was of insufficient size to permit reliable chemical analysis. The size classified fly ash from the inlet of the ESP was used for detailed chemical analyses. Chemical analyses of the fly ash samples from the ESP outlet using a high volume sampler were performed for comparison to the size classified results at the inlet. For all test conditions the particulate removal efficiency of the ESP exceeded 99.3% and emissions were less than the NSPS limits of ≈48 mg/dscm. With constant combustion conditions, the removal efficiency of the ESP increased as the ESP voltage and Specific Collection Area (SCA) increased. The associated decrease in particle emissions occurred in size fractions both larger and smaller than 2.5 microns. For constant ESP voltage and SCA, the removal efficiency for the ultra low-NOx combustion ash (99.4-99.6%) was only slightly less than for the low-NOx combustion ash (99.7%). The decrease in removal efficiency was accompanied by a decrease in ESP current. The emission of PM{sub 2.5} from the ESP did not change significantly as a result of the change in combustion conditions. Most of the increase in emissions was in the size fraction greater than 2.5 microns, indicating particle re-entrainment. These results may be specific to the coal tested in this program. In general, the concentration of inorganic elements and trace species in the fly ash at the ESP inlet was dependent on the particle size fraction. The smallest particles tended to have higher concentrations of inorganic elements/trace species than larger particles. The concentration of most elements by particle size range was independent of combustion condition and the concentration of soluble ions in the fly ash showed little change with combustion condition when evaluated on a carbon free basis.
Download or read book NOx CONTROL OPTIONS AND INTEGRATION FOR US COAL FIRED BOILERS written by and published by . This book was released on 2001 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the third Quarterly Technical Report for DOE Cooperative Agreement No: DE-FC26-00NT40753. The goal of the project is to develop cost effective analysis tools and techniques for demonstrating and evaluating low NOx control strategies and their possible impact on boiler performance for firing US coals. The Electric Power Research Institute (EPRI) is providing cofunding for this program. This program contains multiple tasks and good progress is being made on all fronts. A Rich Reagent Injection (RRI) design has been developed for a cyclone fired utility boiler in which a field test of RRI will be performed later this year. Initial evaluations of RRI for PC fired boilers have been performed. Calibration tests have been developed for a corrosion probe to monitor waterwall wastage. Preliminary tests have been performed for a soot model within a boiler simulation program. Shakedown tests have been completed for test equipment and procedures that will be used to measure soot generation in a pilot scale test furnace. In addition, an initial set of controlled experiments for ammonia adsorption onto fly ash in the presence of sulfur have been performed that indicates the sulfur does enhance ammonia uptake.
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 Department of the Interior and related agencies appropriations for fiscal year 1986 written by United States. Congress. Senate. Committee on Appropriations. Subcommittee on the Department of the Interior and Related Agencies and published by . This book was released on 1985 with total page 936 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Energy Research Abstracts written by and published by . This book was released on 1992-04 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Monthly Catalog of United States Government Publications written by and published by . This book was released on 1982 with total page 1090 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Monthly Catalogue United States Public Documents written by and published by . This book was released on 1982 with total page 1094 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NOx Modelling and Prediction written by Ruksana Moreea-Taha and published by . This book was released on 2000 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Report summaries written by United States. Environmental Protection Agency and published by . This book was released on 1983 with total page 1584 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Why Communists are Not of the Left written by David Spitz and published by . This book was released on 1949 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book REDUCTION OF NOx EMISSION FROM COAL COMBUSTION THROUGH OXYGEN ENRICHMENT written by University of Wyoming Research Corporation. Western Research Institute and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: BOC Process Gas Solutions and Western Research Institute (WRI) conducted a pilot-scale test program to evaluate the impact of oxygen enrichment on the emissions characteristics of pulverized coal. The combustion test facility (CTF) at WRI was used to assess the viability of the technique and determine the quantities of oxygen required for NOx reduction from coal fired boiler. In addition to the experimental work, a series of Computational Fluid Dynamics (CFD) simulations were made of the CTF under comparable conditions. A series of oxygen enrichment test was performed using the CTF. In these tests, oxygen was injected into one of the following streams: (1) the primary air (PA), (2) the secondary air (SA), and (3) the combined primary and secondary air. Emission data were collected from all tests, and compared with the corresponding data from the baseline cases. A key test parameter was the burner stoichiometry ratio. A series of CFD simulation models were devised to mimic the initial experiments in which secondary air was enriched with oxygen. The results from these models were compared against the experimental data. Experimental evidence indicated that oxygen enrichment does appear to be able to reduce NOx levels from coal combustion, especially when operated at low over fire air (OFA) levels. The reductions observed however are significantly smaller than that reported by others (7-8% vs. 25-50%), questioning the economic viability of the technique. This technique may find favor with fuels that are difficult to burn or stabilize at high OFA and produce excessive LOI. While CFD simulation appears to predict NO amounts in the correct order of magnitude and the correct trend with staging, it is sensitive to thermal conditions and an accurate thermal prediction is essential. Furthermore, without development, Fluent's fuel-NO model cannot account for a solution sensitive fuel-N distribution between volatiles and char and thus cannot predict the trends seen in the experiment.
Download or read book written by and published by . This book was released on 1994 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 NOx Emissions from Pulverized coal Arch fired Boilers written by and published by . This book was released on 1982 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NOx reduction by furnace air staging and reburning application of pilot scale testing written by G. Hesselmann and published by . This book was released on 1997 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt:
