Download or read book Role of Fly Ash in Heavy Metal Removal from Flue Gas Final Report September 1 1993 August 31 1994 written by and published by . This book was released on 1995 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: The primary objective of this work is to study the fundamental phenomena involved in the sorption of trace chalcophilic elements by fly ash at high and medium temperatures. Chalcophiles are the low-boiling trace elements that are volatilized during pulverized coal combustion and are transferred to the gas phase, e.g., As, Pb, Cd and Se. The main focus of this work is investigating the sorption phenomena of a representative chalcophile, arsenic (As) on fly ashes at temperatures representative of the upper-furnace region (850--1200°C) and the economizer section (375--600°C). Arsenic is chosen because it is a highly toxic chalcophile and shows some affinity for fly ash but is also emitted from the stack as vapor and aerosol particles. The two temperature zones have been chosen because most of the dry-sorbent injection technologies are being developed for application in these two regions. Also, various fly ash samples from different sources are being studied because their chemical composition and subsequently their chemical sorption characteristics would show a great deal of variation depending on their source. In the first year of this project, it was proposed to conduct isothermal sorption experiments in a differential reactor system. The first year's work was divided into two phases; namely (1) design, construction, testing and trouble-shooting of the differential reactor assembly and the analytical instrumentation, and, (2) designing experiments and conducting sorption studies in the differential reactor system.
Download or read book Role of Fly Ash in Heavy Metal Removal from Flue Gas Final Report September 1 1994 February 29 1996 written by and published by . This book was released on 1996 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: The work is mainly focused towards investigating the sorption phenomena of a representative chalcophile, arsenic (As) species, on fly ashes at temperatures representative of the upper-furnace region (850 -1200°C) and the economizer section (375-600°C). Arsenic is chosen because it is a highly toxic chalcophile and shows some affinity for fly ash but is also emitted from the stack as vapor and aerosol particles. Based on the preliminary thermodynamic analyses it was determined that under the temperature ranges of interest (400- 600°C and 800-1000°C) arsenic trioxide (As2O3) is the main arsenic species in the flue gas environment. The two temperature zones have been chosen because most of the dry-sorbent injection technologies are being developed for application in these two regions. Also various fly ash samples from different sources are being studied because their chemical composition and subsequently their chemical sorption characteristics would show a great deal of variation depending on their source. Studies were also conducted with calcium hydroxide as the chosen representative dry sorbent. This served as comparative studies between fly ash and dry sorbents. This will enable us to predict the behavior of arsenic when exposed to both fly ash and sorbent which is the case under actual boiler conditions. Experimental results show that Ca(OH)2 captures significant amounts of arsenic species. To gain further insight into the capturing mechanism of calcium hydroxide experiments were performed at various temperatures and exposure times.
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 1994 with total page 698 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 Flue Gas and Fly Ash written by P.F. Sens and published by CRC Press. This book was released on 2003-09-02 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of a contractors' meeting organized by the Commission of the European Communities, Directorate-General XII for Science, Research and Development, held in Brussels, Belgium, 16 June 1988.
Download or read book Coal Fly Ash Beneficiation written by Segun Akinyemi and published by BoD – Books on Demand. This book was released on 2018-01-31 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present book deals with various, very significant topics of coal fly ash beneficiation, such as treatment of acid mine drainage with coal fly ash, toxic metal adsorption using coal fly ash, recovery of metals from coal fly ash and phytoreclamation of abandoned acid mine drainage site after treatment with coal fly ash, the status of research in coal fly ash utilization and applications and some other related topics in this growing and increasingly important research area. Overall, coal fly ash beneficiation has come to assume an important role in most areas of waste management research today. Continued growth and emphasis on scientific research is expected in all areas of waste management and conversion of waste to wealth technologies.
Download or read book Chemistry of Trace Elements in Fly Ash written by Kenneth S. Sajwan and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 347 pages. Available in PDF, EPUB and Kindle. Book excerpt: The accumulation of large amounts of ash from fossil fuel combustion for electric power plant generation is becoming a major environmental concern in the United States. Furthermore, stringent environmental regulations mandated by the Environmental Protection Agency through the Clean Air Act, Clean Water Act, Resource Conservation and Recovery Act, as well as state and local environmental regulations may result in even more ash production with subsequent contact with the environment. The concentrations of trace elements in coal residues are extremely variable and depend on the composition of the original coal, conditions during combustion, the efficiency of emission control devices, storage and handling ofbyproducts, and climate. The research papers in this book were presented as a part of the Sixth International Conference on the Biogeochemistry of Trace Elements held at the University of Guelph, Ontario, Canada, from July 29-August 2, 2001. The purpose of this corit'erence was to present current knowledge on the source, pathways, behavior and effects of trace elements in soils, waters, plants and animals. In addition, the book also includes invited research papers from scientists who have done significant research in the area of coal and coal combustion byproducts. All the research papers presented herein have been subjected to peer review.
Download or read book Plasm assisted Cleanup of Flue Gas Final Technical Report September 1 1992 Through August 31 1993 written by Shirshak K. Dhali and published by . This book was released on 1993 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Use of Fly Ash for the Removal of Heavy Metals from Water written by David Craig Markey and published by . This book was released on 1972 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cumulated Index Medicus written by and published by . This book was released on 1993 with total page 1356 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Plasma assisted Cleanup of Flue Gas Final Technical Report September 1 1993 August 31 1994 written by and published by . This book was released on 1994 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book INIS Atomindex written by and published by . This book was released on 1995 with total page 640 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Contamination of Groundwater by Heavy Metals from the Land Disposal of Fly Ash Technical Progress Report June 1 1976 August 31 1976 written by and published by . This book was released on 1976 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A useful method of differentiating surface from total heavy metals associated with fly ash is selective extraction for those metal oxide sinks (Fe, Al, Mn) with which the heavy metals have become associated. This association is important in defining the release of the metals in aqueous environments. This desorption, as well as subsequent adsorption onto local soil matter is pH dependent, lower pH values favoring greater release or less adsorption in the system. Another aspect of trace metal chemistry is solubility, which generally decreases with increasing pH. In view of this pH dependency, it would appear that the more critical case of potential contamination of water resources is that of the acid fly ashes, i.e., those where iron oxide deposits control the pH of the system. The problem could be reduced by maintaining the ash in a neutral or alkaline environment, although at extremely high pH values (approximately 12) the desorbtive tendency of most metals increased slightly. Even at neutral pH values, soluble complexes may increase the concentration of a given metal in excess of solubility. The average percentage of metals released for all fly ashes studied from their surface sinks at pH = 9 were cadmium--17 percent, lead--8 percent, chromium--6 percent, copper--1 percent, and zinc less than 1 percent. Another important factor is the absolute amount of metal on the surface. For instance, even though copper is released very little at neutral pH's, surface concentrations up to 200 .mu.g/g of fly ash were found.
Download or read book Removal of Heavy Metals by Fly Ash written by Chih-Huang Weng and published by . This book was released on 1990 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Contamination of Groundwater by Heavy Metals from the Land Disposal of Fly Ash Technical Progress Report June 1 1977 March 31 1978 written by and published by . This book was released on 1978 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A study has been undertaken on a specific ponded fly ash disposal site to determine the degree of subsurface leaching of various ionic forms, especially heavy metals. The location is the site of the Michigan City generating station of the Northern Indiana Public Service Company, Michigan City, Indiana. The present ash ponding system consists of two primary ash ponds (volume of each 16.5 million gallons) which are loaded alternately, i.e., when one is in service the other is allowed to dry for the removal operation. The ash is sluiced to the ponds in a concentrated slurry. After primary and secondary settling the water is brought back for further ash sluicing. A constant elevation is maintained in the ponds at approximately 31.5 feet above the surface of Lake Michigan. The system cannot be considered closed because of losses due to evaporation and subsurface leaching. The station produces 340 to 400 tons of fly ash per day when operating at full capacity. A typical pond cycle requires six to nine months between removal periods. Observation wells were installed at various locations. Typically, the chemical composition of the groundwater varied with both time in the pond cycle as well as distance from the pond. Heavy metal concentrations decreased rapidly from the rather high levels found in the pond but a smaller peak concentration occurred some 100 meters from the pond after which the concentration decreased to rather low levels. The dominant mechanisms of attenuation are adsorption of metals onto hydrous oxides of iron and manganese and precipitation of various solid phases.
Download or read book Final Report on Removal of Fly Ash by Fluidized Bed Techniques written by John Patrick Pilney and published by . This book was released on 1968 with total page 55 pages. Available in PDF, EPUB and Kindle. Book excerpt:
