Download or read book Fundamental Study of Ash Formation and Deposition Effect of Reducing Stoichiometry Final Report April 1 1993 June 30 1995 written by and published by . This book was released on 1995 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fundamental Study of Ash Formation and Deposition written by Lawrence E. Bool and published by . This book was released on 1995 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fundamental Study of Ash Formation and Deposition written by and published by . This book was released on 1995 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt: The technical objectives of this project are to: identify the partitioning of inorganic coal constituents among vapor, submicron fume, and fly ash products generated during combustion; identify fundamental processes of mineral transformation;incorporate the effects of combustion stoichiometry into an engineering model for ash formation.

Download or read book Fundamental Study of Ash Formation and Deposition written by and published by . This book was released on 1993 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: This project is designed to examine the effects of combustion stoichiometry on the fundamental aspects of ash formation and ash deposit initiation. Technical objectives are: to identify the partitioning of inorganic coal constituents among vapor, submicron fume, and fly ash products generated during the combustion of pulverized coal; to identify and quantify the fundamental processes by which the transformations of minerals and organically-associated inorganic species occur, and; to incorporate the effects of combustion stoichiometry into an Engineering Model for Ash Formation. Specific accomplishments during this quarter are as follows: The Project Program Plan was prepared and the subcontractors were authorized to begin work in this program. Acquisition of pyrite and kaolinite minerals for use in synthetic char production was begun. A fragmentation submodel was completed and incorporated into the PSI Engineering Model for Ash Formation (EMAF) that was developed previously.

Download or read book Fundamental Study of Ash Formation and Deposition written by and published by . This book was released on 1993 with total page 89 pages. Available in PDF, EPUB and Kindle. Book excerpt: The technical objectives of this project are: To identify the partitioning of inorganic coal constituents among vapor, submicron fume, and fly ash products generated during the combustion of pulverized coal under a variety of combustion conditions. Fuel lean and fuel rich combustion conditions will be considered. To identify and quantify the fundamental processes by which the transformations of minerals and organically-associated inorganic species occur. Emphasis will be placed on identifying any changes that occur as a result of combustion under sub-stoichiometric combustion conditions. To incorporate the effects of combustion stoichiometry into an Engineering Model for Ash Formation based upon the understanding developed in (a) and (b). When completed, this model wig predict the particle size and chemical composition distributions of ash formed during the combustion of pulverized coal under a broad range of conditions. The work discussed in this report highlights the accomplishments of the second quarter of this two year project. This includes the final selection of coals by PSI PowerServe, the results of initial in-situ XAFS combustion measurements by the University of Kentucky, a review of the status of ash formation and deposition models by MIT, modeling of iron behavior during coal combustion by the University of Arizona, preliminary work on the redistribution of minerals within char during the early stages of combustion by PSI PowerServe, and the incorporation of a char fragmentation mechanism into the ash formation model by PSI PowerServe.

Download or read book Fundamental Study of Ash Formation and Deposition written by and published by . This book was released on 1994 with total page 78 pages. Available in PDF, EPUB and Kindle. Book excerpt: The technical objectives of this project are: (a) to identify the partitioning of inorganic coal constituents among vapor, submicron fume, and fly ash products generated during the combustion of pulverized coal under a variety of combustion conditions. Fuel lean and fuel rich combustion conditions will be considered. (b) To identify and quantify the fundamental processes by which the transformations of minerals and organically-associated inorganic species occurs. Emphasis will be placed on identifying any changes that occur as a result of combustion under substoichiometric combustion conditions. (c) To incorporate the effects of combustion stoichiometry into an Engineering Model for Ash Formation based upon the understanding developed in (a) and (b). When completed, this model will predict the particle size and chemical composition distributions of ash formed during the combustion of pulverized coal under a broad range of conditions.

Download or read book Fundamental Study of Ash Formation and Deposition written by and published by . This book was released on 1995 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objectives of this research program include: the identification of the partitioning of inorganic coal constituents among vapor, submicron fume, and fly ash products generated during pulverized coal combustion; identification of fundamental processes by which the transformation of minerals and organically associated species occurs; the incorporation of the effects of combustion stoichiometry into an engineering model for ash formation.

Download or read book Fundamental Study of Ash Formation and Deposition written by and published by . This book was released on 1994 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt: The technical objectives of this project are: (a) To identify the partitioning of inorganic coal constituents among vapor, submicron fume, and fly ash products generated during the combustion of pulverized coal under a variety of combustion conditions. Fuel lean and fuel rich combustion conditions will be considered. (b) To identify and quantify the fundamental processes by which the transformations of minerals and organically associated inorganic species occurs. Emphasis will be placed on identifying any changes that occur as a result of combustion under sub-stoichiometric combustion conditions. (c) To incorporate the effects of combustion stoichiometry into an engineering model for ash formation based upon the understanding developed in (a) and (b). When completed, this model will predict the particle size and chemical composition distributions of ash formed during the combustion of pulverized coal under a broad range of conditions.

Download or read book Fundamental Study of Ash Formation and Deposition written by and published by . This book was released on 1995 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: The technical objectives of this project are: (a) To identify the partitioning of inorganic coal constituents among vapor, submicron fume, and fly ash products generated during the combustion of pulverized coal under a variety of combustion conditions. Fuel lean and fuel rich combustion conditions will be considered. (b) To identify and quantify the fundamental processes by which the transformations of minerals and organically-associated inorganic species occur. Emphasis will be placed on identifying any changes that occur as a result of combustion under sub-stoichiometric combustion conditions. (c) To incorporate the effects of combustion stoichiometry into an Engineering Model for Ash Formation based upon the understanding developed in (a) and (b). When completed, this model will predict the particle size and chemical composition distributions of ash formed during the combustion of pulverized coal under a broad range of conditions. The work discussed in this report highlights the accomplishments of the seventh quarter of this two year project. This includes University of Arizona efforts to minimize periodicity in the coal feeder for the drop tube furnace, and MIT efforts to calculate the concentrations of CO, CO2, and O2 surrounding a burning char particle. In Section 3, the use of a pulsed gas flow to maintain a smooth coal feed to the drop tube furnace is discussed. Addition of pulsing action, driven by a peristaltic pump, has eliminated the coal feeder pluggage problems that had been occurring. In Section 4, the development of a single particle char combustion model by MIT is discussed. The model is then used for calculating oxygen, CO, and CO2 concentrations on the char particle surface as a function of char particle diameter. This information can then be used to interpret results of ash formation experiments conducted as a function of particle size and combustion stoichiometric ratio.

Download or read book Fundamental Study of Ash Formation and Deposition Effect of Reducing Stoichiometry written by and published by . This book was released on 1994 with total page 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 1995 with total page 782 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Announcements Index written by and published by . This book was released on 1996-09 with total page 1244 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Annual Index written by and published by . This book was released on 1995 with total page 1686 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sections 1-2. Keyword Index.--Section 3. Personal author index.--Section 4. Corporate author index.-- Section 5. Contract/grant number index, NTIS order/report number index 1-E.--Section 6. NTIS order/report number index F-Z.

Download or read book Investigation of Mineral Transformations and Ash Deposition During Staged Combustion Quarterly Technical Progress Report April 1 1997 June 30 1997 written by and published by . This book was released on 1997 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes work performed in the fifteenth quarter of a fundamental study to examine the effect of staged combustion on ash formation and deposition. Efforts this quarter included addition of a new cyclone for improved particle sampling and modification of the existing sampling probe. Particulate samples were collected under a variety of experimental conditions for both coals under investigation. Deposits formed from the Black Thunder coal were also collected. Particle size and composition from the Pittsburgh No. 8 ash samples support previously reported results. In addition, the authors ability to distinguish char/ash associations has been refined and applied to a variety of ash samples from this coal. The results show a clear difference between the behavior of included and excluded pyrite, and provide insight into the extent of pyrite oxidation. Ash samples from the Black Thunder coal have also been collected and analyzed. Results indicate a significant difference in the particle size of {open_quotes}unclassifiable{close_quotes} particles for ash formed during staged combustion. A difference in composition also appears to be present and is currently under investigation. Finally, deposits were collected under staged conditions for the Black Thunder coal. Specifically, two deposits were formed under similar conditions and allowed to mature under either reducing or oxidizing conditions in natural gas. Differences between the samples due to curing were noted. In addition, both deposits showed skeletal ash structures which resulted from in-situ burnout of the char after deposition.

Download or read book Investigation of Mineral Transformation and Ash Deposition During Staged Combustion Final Report October 1 1993 September 30 1997 written by and published by . This book was released on 1997 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this report is to document a recently completed four-year study to examine the impact of low-NOx firing technologies on ash formation and deposition while firing pulverized coal. Low-NOx burners and staged combustion inhibit NOx formation by restricting the amount of oxygen available to form a fuel-rich zone in which nitrogen compounds are reduced to molecular nitrogen (N2) rather than oxidized. Additional oxygen is provided downstream for complete combustion. Consequently, coal and mineral particles encounter different temperatures and oxygen concentrations when they are burned under low-NOx firing conditions than they do in conventionally-fired units. Two coals with distinctly different inorganic contents and ash characteristics were fired in a pilot-scale laboratory combustor under both conventional and staged combustion conditions. Ash and deposit samples were collected at various locations in the reactor and analyzed in order to assess the influence of staged combustion. This report is organized as follows. First, a background section provides the foundation needed in order to understand the motivation for and the results of the experimental program. The next section presents a description of the experimental apparatus and procedures, including the development the analytical methods critical to the study. Results of the analyses of coal, ash and deposit samples are then presented and discussed for each of the two coals. Finally, the report ends with a short summary and statement of conclusions.

Download or read book Suppression of Fine Ash Formation in Pulverized Coal Flames Quarterly Technical Progress Report No 3 April 1 1993 June 30 1993 written by and published by . This book was released on 1993 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the major obstacles to the economical use of coal is managing the behavior of its mineral matter. Ash size and composition are of critical importance for a variety of reasons. Fly ash size and emissivity affect radiant furnace heat transfer. Heat transfer is also affected by the tendency of ash to adhere to heat transfer surfaces, and the properties of these deposits. Removal of ash from flue gas by electrostatic precipitators is influenced by both particle size and particle resistivity. The efficiency of fabric filter-based cleaning devices is also influenced by ash size. Both types of devices have reduced collection efficiencies for smaller-sized particles, which corresponds to the size most efficiently retained in the alveolar region of the human lung. Laboratory work and studies of full-scale coal-fired boilers have identified two general mechanisms for ash production. The vast majority of the ash is formed from mineral matter that coalesces as the char burns, yielding particles that are normally larger than 0.5 [mu]m. The second major mechanism is the generation of a submicron aerosol through a vaporization/condensation mechanism. Although these particles represent a relatively small fraction of the mass, they can present a large fraction of the surface area. Thus, they are a preferred site for the condensation of the more volatile oxides later in the furnace. This leads to a layering effect in which the refractory oxides are concentrated at the particle core and the more volatile oxides reside at the surface. This also explains the enrichment of the aerosol by volatile oxides that has been noted in samples from practical furnaces. These volatile metal oxides include the majority of the toxic metal contaminants, e.g., mercury, arsenic, selenium and nickel. Risk assessment studies suggest that toxic metal emissions represent a significant portion of the health risk associated with combustion.

Download or read book Investigation of Mineral Transformations and Ash Deposition During Staged Combustion Quarterly Technical Progress Report October 1 1993 December 31 1993 written by and published by . This book was released on 1994 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: A thorough understanding of the fundamental processes which govern the mineral behavior is essential to the development of tools to predict and manage ash deposition. The purpose of the current project is to perform a fundamental study of mineral transformations and ash deposition during staged combustion of pulverized coal. Staging of combustion air is a strategy used to reduce NO(subscript x) emissions from coal-fired units. It is applicable to both advanced combustion systems currently under development (e.g. HITAF) and low NO(subscript x) retrofits for existing units. These low NO(subscript x) combustion strategies produce fuel rich or reducing conditions in the lower furnace. Therefore, the combustion history of the coal particles is significantly changed from that experienced under normal combustion conditions. A carefully designed experimental study is needed to examine the effects of altered combustion conditions on mineral matter release, fly ash formation, particle stickiness and deposit formation. This project uses state-of-the-art analytical equipment and a well-characterized laboratory combustor to address this need. This report describes work in the initial quarter of a fundamental, three-year study of mineral transformations and ash deposition during staged combustion.