Slagging incinerators

The primary function of incineration processes is to reduce the volume of the refuse and at the same time to effect its sterilization. This is accomplished by reacting (i.e., burning) the refuse with air or oxygen at temperatures ranging from 1000-1400°C (1800-2600°F) by which it is possible to achieve a reduction in volume which ranges from 85 to 90% for conventional incinerators to some 97% for the high-temperature slagging incinerators. 

Sohd wastes are treated in a soHd waste disposal area to reduce thein volume and or toxicity prior to final disposal in a secured landfill. Combustible wastes can be incinerated in a slagging rotary kiln to reduce volume and toxicity. 

George, A. M. Chemical Control of Slagging in Incinerators and Other Combustion Equipment. Marston-Bentley technical literature. Canning Group, P.L.C., UK, 1993. 

Schofield, W.R. Lutzman, John Patterson, Gene W. Use of Chemical Additives to Reduce The Impact of Slag Formation in Hazardous Waste Incineration. Hazardous Materials Control Journal, USA, 1992. 

Dissolution. Plutonium is solubilized in nitric acid solutions at Rocky Flats. The feed material consists of oxide, metal and glass, dissolution heels, incinerator ash and sand, slag, and crucible from reduction operations. The residues are contacted with 12M HNO3 containing CaF2 or HF to hasten dissolution. Following dissolution, aluminum nitrate is added to these solutions to complex the excess fluoride ion. 

Metals in the feedstock end up in slag and fines. The slag meets the quality standards of the Dutch Building decree, and the fines have a comparable quality to municipal solid waste incineration (MSWI) fly-ash (a.4). 

The synthesis gas is mainly used for the production of methanol (70%). Another part (20%) is used for electricity production. Waste gas products are incinerated the fate of any chlorine is not clear from the various descriptions available. Inorganic materials are converted into a slag, with low leaching characteristics (landfill class 1 according to the German TA Siedlungsabfall). 

MSWIs can accept virtually any mixed waste stream as long as it falls within its calorific window of 9-13 MJ/kg (hence including material containing regular plastics and PVC content). Furthermore, the heavy metal content should not be excessive (since this can make the quality of the slag not suitable for re-use) and the material should be destructible at the rather low incineration temperature of MSWIs (850 °C). Some waste will not be efficiently destroyed. 

Fireclay bricks are used in kilns, malleable-iron furnaces, incinerators, and many portions of metallurgical furnaces. They are resistant to spalling and stand up well under many slag conditions but are not generally suitable for use with high-lime slags or fluid-coal-ash slags or under severe load conditions. 

Incineration produces gases and solids, in the form of ash and slag. Combustion gases are composed primarily of carbon dioxide and water, as well as small quantities of carbon monoxide, nitrogen oxides, and small concentrations of organic and inorganic compounds. 

The vendor states that MBS stabihzes heavy metals in soil, slndges, slag, ash, baghonse dnst, and sediment. Among the heavy metals treatable by the MBS process are arsenic, cad-minm, chrominm, copper, lead, mercnry, nickel, silver, and zinc. MBS technology is applicable in the following indnstries primary and secondary smelters, battery mannfactnrers and recyclers, ferrons and nonferrons fonndries, mnnicipal solid waste incinerators, anto and metal scrap recyclers, electronic mannfactnrers, electroplaters, ceramic prodnct mannfactnrers, and mineral refiners and processors. 

The Sonotech Cello pulse combustion system has the same limitations as a nonpulsating burner attached to a combustion device. Preliminary testing of the Sonotech system showed that in order to prevent slag formation, the temperature of the rotary kiln gas should not exceed 1700°F. The system produces considerable noise, which may be controlled by sound insulation. The Sonotech system uses resonant frequency of the incinerator to create pulsations. In an older incinerator, if the sound energy is not properly applied, the Sonotech system could cause structural problems. 

Mayer, A. Rey, T. 1996. Innovative HSR process to transform waste incinerator slag into useful mineral additives. Waste Management, 16, 27-33. 

Lancellotti, I. Manfredini, T. 2002. Utilization of municipal incinerator grate slag for porcelanized stoneware tiles manufacturing. Journal of the European Ceramic Society, 22, 1457-1462. 

Falcone, R., Hreglich, S., Profilo, B. Vallotto, M. 2003. Inertization by vitrification of mixtures of municipal waste incineration slag and ash and valorisation of the obtained glass products. Rivista della Stazione Sperimentale del Vetro, 4, 25-29. 

In addition the walls of the combustion chamber must also be shielded from corrosive slag. Chemical waste is mostly incinerated in a rotating tubular oven coated with chromium-containing corundum stone or phosphate-bound corundum stone. 

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