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search Fly Ash Resource Center(coal combustion products) RESEARCH QUALITY CONTROL SPECIFICATIONS ENVIRONMENTAL CHEMISTRY MSDS MARKETPLACE SUPPLIERS LIBRARY BENEFICIATION IMAGES MARKET LinksORGANIZATIONS POZZOLAN ROADBASE SOIL STABILIZATION WASTE STABILIZATION CONFERENCES LINKS VIDEO RCRA COAL COMBUSTION PRODUCTS (CCBs) Fossil fuels are used in modern power plants throughout the world to produce electrical energy. The inorganic residue, that remains after pulverized coal is burned, is known as 'Coal combustion products'. Coal combustion products (CCBs) rapidly accumulate and cause enormous problems of disposal unless a way can be found to utilize these by-products through resource recovery programs. Using coal fly ash conserves energy by reducing the demand for typical pavement materials such as lime, cement and crushed stone, which take energy to produce. Each ton of fly ash used to replace a ton of cement, for example, saves the equivalent of nearly one barrel of imported oil. Also less greenhouse gases are produced that would otherwise contribute to global warming. Every ton of ash reused in cement products equates to nearly a ton of CO2 savings. Coal fly ash can also replace clay, sand, limestone and gravel, and save the energy costs of mining such materials. In the United States, production for 2005 were 71.1 million tons of coal fly ash, 17.6 million tons of bottom ash, 1.96 million tons of boiler slag, 11.98 million tons of FGD Gypsum, 19.7 million tons of FGD Material- Scrubber (wet and dry) and 1.37 million tons FBC. Total production of all ash products in 2006 was 125 million tons. See American Coal Ash Association (ACAA) for details. The production figures in Europe in 2001 were (in thousand metric tonnes: 39.95 fly ash, 5.84 bottom ash, 2.24 boiler slag and 1.06 FBC ash. Please contact the European Association for Use of By-Products of Coal-Fired Power Stations (ECOBA) for more information. Britain's coal-fired power stations generate around 10 million tonnes of pulverised fuel ash (PFA) waste every year. This presents a massive disposal problem, but it can be reduced by using some of the PFA in a variety of construction applications, including concrete. Nearly a million tons of PFA are used in concrete in Britain each year. It replaces part (typically 25 to 30%) of the concrete's cement content, thus reducing costs. For information on Canada, see the Association of Canadian Industries Recycling Coal Ash. Australian coal-fired power stations produced over 13 million tonnes of total ash in 2003. Approximately 10% of this is incorporated into cement and concrete; the rest ends up in unsightly ash dams. For information on Australia, see the Ash Development Association of Australia. It is the intent of the Fly Ash Resource Center to promote the utilization of fly ash, boiler slag, and bottom ash through the dissemination of knowledge, research, and project activities. It is hoped the reader becomes an active participant and shares his/her knowledge and activities by signing and reading the guestbook. Increased utilization of coal combustion products minimizes disposal costs (costs which are economic and environmental). Coal Combustion Products (CCBs)Defined: Coal Fly Ash is the finely-divided and powdery coal combustion product collected by electrostatic precipitators or baghouses from the flue gases. It is produced from the burning of pulverized coal in a coal-fired boiler. Boiler slag and Bottom ash are the heavier and coarser coal combustion products. There are three types of coal-fired boiler furnaces used in the electric utility industry. They are referred to as dry-bottom boilers, wet-bottom boilers and cyclone furnaces. When coal is burned in the most common type, the dry-bottom boiler, 80% leaves as fly ash and 20% as bottom ash. Bottom ash is gray to brown, granular, porous, predominantly sand size minus 12.7mm (˝ in) material that is collected in a water-filled hopper at the bottom of the furnace. Boiler Slag is produced from either the slag-type boiler or the cyclone boiler. In each type, the ash is kept in a molten state and tapped off as a liquid. Both boiler types have a solid base with an orifice that can be opened to permit the molten ash that has collected at the base to flow into the ash hopper below. The ash hopper in wet-bottom furnaces contains quenching water. When the molten slag comes in contact with the quenching water, it fractures instantly, crystallizes, and forms pellets. The resulting boiler slag, often referred to as “black beauty,” is a coarse, hard, black, angular, glassy material.   Fly ash Concrete in Marina City (Chicago)   Fly Ash concrete in Sears Tower and River City (Chicago)   Orchid Hotel is a good example of environmental responsibility. The Orchid Hotel in Mumbai, India received an Ecotel Certification for using recycled materials like fly ash. FLY ASH SYSTEMS MIDWEST CONCRETE CONSORTIUM-RELATED LINKS(cement associations, library sites, government sites, other organizations, etc.) NEWSGROUPS: sci.materials, sci.environment.waste,sci.engr.civil,misc.industry.utilities.electric  RESOURCE CONSERVATION AND RECOVERY ACT ( RCRA) Materials Research The shape. fineness, particle-size distribution, density, and composition of fly ash particles influence the properties of end use products. Fly Ash produced at different power plants or at one plant with different coal sources may have different colors. And particle size and shape characteristics of fly ash are dependent upon the source and uniformity of the coal, the degree of pulverization prior to burning, and the type of collection system used. Rapid cooling of the ash from the molten state as it leaves the flame causes fly ash to be predominantly noncrystalline (glassy) with minor amounts of crystalline constituents, such as mullite, quartz, magnetite (or ferrel spinel), and hematite. Other constituents which may be present in high-calcium fly ash include periclase, anhydrite, lime, alkali sulfate, melilite, merwinite, nepheline, sodalite, C3S,and C2A. Fly Ash particles, carried out of the boiler by the exhaust gases, are extremely variable but have some characteristics of interest. The particles are generally less than 250 micrometres in size, spheroidal, have a high mechanical strength, a range of densities from about 3 to less than 0.6, a melting point above 1000ďż˝C, low thermal conductivity and are mostly chemically inert. See Fly Ash as an engineered construction material.   Materials Research is conducted at universities and organizations throughout the world. This research leads to new ideas and uses for CCBs.   Standards/Quality Assurance A quality assurance program is required in order to assure the end user that the CCB is acceptable for its intended application by meeting certain standards. See fly ash quality control tests. Fly Ash Marketplace   Written by R. Majko.  E-mail: rmajko@yahoo.com   Sign Guestbook View Guestbook Read guestbook I KEYWORDS/Schlüsselwörter/Palabras Claves:     Bottom Ash : cendres mâchefers, cendres de fond, cenizas de fondo, ceneri pesanti, Kesselsand, piasek żużlowy, bodemas (ketelzand), אפר תחתי (Hebrew), 灰渣 (Chinese)    Boiler slag : scories de chaudičre, escoria de la caldera, Schmelzkammergranulat     coal combustion byproducts : CCBs, coal combustion products, produits dérivés de combustion du charbon, derivados de la combustion del carbón, Kohlekraftwerke Produkt, ubocznych produktów spalania .     Fly Ash : fly ash, אפר מרחף (Hebrew), رماد متطاير (Arabic), Class F fly ash, Class C fly ash, self-cementing fly ash,flugasche, vliegas, flygaska, flyveaskes, lentotuhka, cendres volantes, cendre volante, cenere volante, cenizas volantes, ceneri volanti, cinzas volantes, szállópernye , ιπτάμενη τέφρα (Greek), coal fly ash, Steinkohlenflugasche, steenkoolvliegas, coal ash, אפר הפחם (Hebrew), popílek, popiołów , pyły lotne, popolček (lietavý), летучая зола (Russian), precipitadores electrostaticos, pulverised fuel ash (PFA), poederkoolvliegas, fly ash: 飛灰 (Chinese), coal fly ash: 粉煤灰 (Chinese) Pozzolan :pozolana, pozzolana, puzolani, puzolanik, puzolana, المواد البوزولانية (arabic), سيمان پوزولان (persian), puzolanas, puzolánicos, materialen, pouzzolane, pucolana, Пуцолан, pouzivanych materialu, pozzolanic reaction (puzzolanische reaktion) Use Alta Vista Use Google Use YAHOO .