摘要:
Methods of making finely divided product from fly ash compositions, including both dry fly ash compositions and aqueous suspensions of fly ash in combination with alkaline earth metal compounds. The fly ash composition, preferably including 10 to 50% combined alkaline earth metal oxides, is heated to molten condition while collecting gases evolving therefrom, including sulfur oxide gases. The top portion of the melt is then poured in a manner causing a molten stream thereof to be divided into a multiplicity of fractions and cooled to solid form while encompassed by a fluid cooling medium in a manner to produce either a shot or a granulated aggregate product. The bottom portion of the melt is nearly pure metallic iron which is recovered, as such, for other uses. Preferably, the molten stream impinges on a rotating member in a manner to produce shot, or is quenched in a water bath to form a granulated type product.
摘要:
Improved cementitious composition results from a process comprised of mechanical size reduction and activation of a mixture of lime and fly ash and the addition thereto of fly ash and aggregate, as needed, to make a mix of the desired proportions. A quicker and more complete reaction between the lime and fly ash results from deagglomeration of lime particles caused by interaction with the fly ash and/or by the increased availability of reactant materials due to particle size reduction of both the lime and the fly ash. The mechanical size reduction and activation process may be carried out, for example, in a ball mill or centrifugal impact mill.
摘要:
Improved method for making generally spherical particulate shot-like product comprising permitting a siliceous-aluminous composition of specified characteristics onto a rotating squirrel cage rotor near top dead center thereof and causing said impinging molten material to be projected in droplet form and cooled while suspended in a gaseous cooling medium, such as air, into an amorphous generally spherical product, suitable for use as an abrasive or filler material.
摘要:
Waste sludges containing small amounts of certain types of reactive materials are treated by adding to such sludges materials capable of producing aluminum ions, lime and/or sulfate bearing compounds to produce a composition having a sufficient concentration of sulfate ions, aluminum ions and equivalents thereof, and calcium ions and equivalents thereof. Fly ash is preferred source of aluminum ions for this purpose. Over a period of time such compositions harden by the formation of calcium sulfo-aluminate hydrates. Hardening of the sludge facilitates its disposition and may permit the reclamation of the land now occupied by large settling ponds for such sludge. Still further, the solidification of such settling ponds may provide permanent land fill which permits immediate use of the land without the necessity for removal of the sludge. Aggregate materials may also be incorporated in the solidified waste.
摘要:
Strong dense shaped articles such as pellets suitable for use as gravel substitutes are produced by the described method from solid fly ash-containing water materials obtained by a lime based dry scrubbing flue gas desulfurization operation. In this method the dry ash-containing waste powder, which also contains calcium sulfite or sulfate reaction products and unreacted lime, is first uniformly contacted with a critical amount of water and then immediately compacted at a critical compaction ratio to provide a handleable green body in which the fly ash particles are positioned with respect to one another so that the interstitial spaces are sufficient to accommodate the volumetric changes in wthe cementitious materials without any deleterious expansion of the article as the article is cured.
摘要:
Cured compacted products suitable for use as landfill materials, embankments, roadbase compositions and the like are produced by the described method from fly ash-containing waste materials obtained by a lime based dry scrubbing flue gas desulfurization operation. In this method the dry fly ash-containing waste powder, which also contains calcium sulfite or sulfate reaction products and unreacted lime, is contacted with a predetermined amount of water and mixed under critical mixing conditions to provide a powder/water mixture which is placed at a suitable utilization site, e.g., a landfill disposal site, and compacted under sufficient load to achieve at least about 70% of the laboratory dry density. The resulting products have compressive strengths after curing of at least about 25 psi and permeabilities of less than 1.times.10.sup.-5 cm/sec.
摘要:
A method for stabilizing wet, oily petroleum refinery wastes and other similar wastes without the need for Portland cement. The waste is combined with at least 5 weight percent of a novel cementitious reagent composition comprised of Powder River Basin fly ash and circulating fluid bed combustion ash in weight ratios ranging from 1:9 to 9:1.
摘要翻译:稳定湿,油性炼油厂废物和其他类似废物的方法,无需波特兰水泥。 该废物与至少5重量%的由Powder River Basin飞灰和循环流化床燃烧灰组成的新型水泥质试剂组合物的重量比为1:9至9:1的重量比组合。
摘要:
Digested sewage sludge resulting from sewage plant treatment of municipal sewage is disposed of and used in an ecologically acceptable manner by the incorporation of such sludge in hardenable compositions further including, for example, lime, fly ash and, in some cases, alkaline earth metal sulfates and/or soil or other inert or complimentary additives. These hardenable compositions may be emplaced in an area open to the atmosphere and permitted to cure over a period of time to act as land fill or as road base materials.
摘要:
A process for treating contaminated waste to stabilize environmentally harmful heavy metals. The waste is contacted with a mixture of a sulfide, preferably calcium sulfide, an inorganic phosphate, which prevents oxidation of sulfide, and a base that at least includes calcium hydroxide. The process stabilizes harmful, heavy metal materials in the waste but avoids the prior art disadvantage of emitting hydrogen sulfide.