Pulverized fuel ash

Solid - Asbestos insulation heat treatment salts, pulverized fuel ash refuse... 

Pulverized fuel ash and Waste from power stations Some used As fill and in manufacture... 

Summary cntena for occupational exposure limits 1996 (with updates/changes 1997, 1998, 1999) Tnmethylbenzenes criteria document for an OEL Pulverized fuel ash cntena document for an OEL N,N-dimethylacetamide cntena document for an OEL... 

When coal is combusted a number of ash products are produced. In a conventional coal-fired power station the ash that enters the flue gas stream is referred to as the fly ash or pulverized fuel ash. This is volumetrically the most important fraction and although considerable progress has been made in utilizing this material, nevertheless there is an excess production, much of which ends in lagoons or, on a longer term basis, in landfill sites. The potential impacts of fly ash on surface water and groundwater therefore have to be considered both in the short and long term. The annual European production of fly ash in 2000 was 38.96 x 106 t, of which... 

Many cements used today are composites of Portland cement and industrial waste materials that can enter into the hydration reactions and contribute to the strength of the hardened product. These substances include pulverized fuel ash (PFA) from burning of pulverized coal in thermal power stations, crushed blast-furnace slag (Section 17.7), and natural or artificial pozzolanas—that is, volcanic ash and similar finely particulate siliceous or aluminosilicate materials that can react with the Ca(OH)2 in Portland cement to form hydrated calcium silicates and aluminates. As noted earlier, the solubility of Ca(OH)2 is such that the pH of pore water in Portland cements will be about 12.7, at which the Si-O-Si or Si-O-Al links in the solid pozzolanas will be attacked slowly by OH- to form discrete silicate and aluminate ions and thence hydrated calcium silicate or aluminate gels. 

Jenner, H.A. and Janssen-Mommen, J.P.M. (1989) Phytomonitoring of pulverized fuel ash leachates by the duckweed Lemna minor, in M. Munawar, G. Dixon, C.I. Mayfield, T. Reynoldson and M.H. Sadar (eds.), Environmental Bioassay Techniques and their Application Proceedings of the 1st International Conference held in Lancaster, England, 11-14 July 1988, Kluwer Academic Publishers, Dordrecht, Netherlands, pp. 361-366. 

Due to the increasing cost of energy, the need to preserve the environment, and the non-existence or exhaustion of suitable natural raw materials in some areas, industrial and other waste materials are of interest as possible raw materials or supplementary fuels or both. Energy can be saved if even a part of the CaO can be provided by a material, such as blastfurnace slag, that does not require decarbonation. Supplementary fuels include such materials as used or reject tyres and pulverized household refuse, which can be introduced into the system in various ways. Some materials, such as pulverized fuel ash (pfa fly ash) can serve as raw materials that also possess some fuel content. Other wastes that have been used include calcium silicate residues from aluminium extraction, mining residues, and precipitated calcium carbonate from various industries. 

Pulverized fuel ash (grits) 9 — Pol/eBiylerie pellets 10 — Granulated sugar tl — Peariite... 

On a smaller scale of operations, there are some industrial wastes and mine tailings that are alkaline and potentially more reactive than virgin minerals towards carbon dioxide. These include pulverized fuel ash from coal-fired power stations. In this situation, development of a practical means to react the ash with some of the attendant carbon dioxide would be most beneficial. Indeed, this may prove to be the most expedient route to introducing the technology required for sequestration via mineral carbonation. 

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