Particulate metallic

Utility systems as sources of waste. The principal sources of utility waste are associated with hot utilities (including cogeneration systems) and cold utilities. Furnaces, steam boilers, gas turbines, and diesel engines all produce waste from products of combustion. The principal problem here is the emission of carbon dioxide, oxides of sulfur and nitrogen, and particulates (metal oxides, unbumt... 

Sun, 1994. Jinjun Sun, Benjamin Liu, Peter McMurry, and Stephen Greenwood, A Method to Increase Control Efficiencies for Wet Scrubbers for Submicron Particles and Particulate Metals, J. Air Waste Management Association, 44 2, February 1994. 

Applied water rates for the contact systems are typically about 3600 gal/t of cast product discharge rates for the better controlled casters are less than 25 gal/t. The principal pollutants are total suspended solids, oil, and grease, and low levels of particulate metals.15... 

Colloidal and particulate metal species also contribute to maintaining low free metal ion concentrations. The behaviour of colloidal species of similar size may however be very different, depending on their chemical speciation and on their structure. Metals bound to HA of large size may exchange with the... 

Particulate matter removal, in industrial water treatment, 26 140-141 Particulate metal-matrix composites, 16 179... 

Spray-forming, of particulate metal-matrix composites, 16 175 Spray functions, 23 174t Spray impact, 23 197 measurements, 23 194-195 Spraying processes, for sodium carbonate peroxohydrate, 18 412 Spraying techniques, in fluidized-bed encapsulation, 11 541-542 Spray instrumentation, 23 192-195 Spray irrigation... 

Gongalves, M. S., L. Sigg, and W. Stumm (1985), "Voltammetric Methods for Distinguishing Between Dissolved and Particulate Metal Ion Concentrations in Presence of Hydrous Oxides", Env. Sci. Techn. 19/2, 141-146. 

The data presented in Table 11.1 indicate that the fluvial gross river flux is the major source of trace metals to the oceans and that most of this flux is in particulate form (fluvial gross particulate flux). But the majority of this particulate flux is trapped within estuaries, primarily via settling, and, hence, is not released into the open ocean. As a result, the fluvial net particulate flux is only about 10% of the fluvial gross particulate flux. In seawater, most of this particulate metal remains in solid form due to low solubilities. The particulate metals eventually settle to the seafloor and are subsequently buried in the sediments. In the case of iron, a small fraction of the particulate pool does dissolve. In the surface waters, solubilization of particulate iron can provide a significant amount of this micronutrient to the phytoplankton. 

Sinking particles transport trace elements to the sediments. Once in the sediments, chemical reactions can resolubilize a significant fraction of the particulate metals. This process is termed diagenetic remobilization and is the subject of the next chapter. The resolubilized elements can diffuse across the sediment-water interface into the deep zone. 

Three mechanisms have been proposed to explain how particulate metals could be transported within such sediments so as to support the growth of Fe-Mn nodules (1) anoxic microzones, (2) bioturbation, and (3) shifts in the depth of the redox boundary over time. Anoxic microzones are present within fecal pellets and the interiors of radiolarian shells where detrital POM is still present. Metals mobilized within these microzones should be able to diffuse through the sediments for substantial distances... 

Costa M, Mollenhauer HH. 1980. Carcinogenic activity of particulate metal compounds is proportional to their cellular uptake. Science 209 515-517. 

The high tension ion conduction agglomeration (INCA) system is an ex situ process for the recovery of soluble and particulate metals from aqueous solutions such as mining effluents, process waters, and wastewater. It is not known if the technology is currently commercially available. 

The factors that affect the technical and economic performance of ChemTech soil treatment process technology include the following soil type (sand versus clay) contaminant (metals, petroleum compounds, particulate metals, etc.) type, form, and concentration cleanup objectives (residential, industrial, or risk-based) and the scale of the project. These factors determine optimum operating conditions, process kinetics, the quantity of residuals, and the operating costs (D177360, p. 9). 

The modification of the sand surface allows the grains to simultaneously adsorb soluble heavy metals and remove particulate metals by filtration in a column packed with the media. Important factors to the performance of the adsorbent include pH of the solution to be treated, empty bed detention time (EBDT), and the presence of complexing agents, oil, surfactant, and biodegradable substances. 

After treatment has proceeded for a period of time, either the coating reaches its maximum capacity to remove metals or the filter requires backwashing. At this time, the column can be backwashed to recover particulate metals from the column, and an acidic solution can be used to recover the adsorbed metals, thereby regenerating the column. Because the ferrihydrite is trapped on the sand particles, only the contaminant metals and nonferrihydrite are released. Thus the need to dispose of large amounts of iron oxide with the metal sludge, one of the main drawbacks of a conventional treatment process, is eliminated. 

The literature of the vibrational spectra of adsorbed alkynes (acetylene and alkyl-substituted acetylenes) is very much in favor of single-crystal studies, with fewer reported investigations of adsorption on oxide-supported metal catalysts. Fewer studies still have been made of the particulate metals under the more advantageous experimental conditions for spectral interpretation, namely, at low temperatures and on alumina as the support. (The latter has a wide transmittance range down to ca. 1100 cm-1.) A similar number of different single-crystal metal surfaces have been studied for ethyne as for ethene adsorption. We shall review in more detail the low-temperature work which usually leads to HCCH nondissociatively adsorbed surface structures. Only salient features will be discussed for higher temperature ethyne adsorption that often leads to dissociative chemisorption. Many of the latter species are those already identified in Part I from the decomposition of adsorbed ethene. 

We have seen in Section III,Q that the l29Xe chemical shift of xenon adsorbed on zeolites depends on the zeolite structure, the kind of cation, and the pressure of xenon gas. When particulate metal is present in the zeolitic cavities, an extra term must be added to Eq. (27) (341-344). Curve (a) in Fig. 68 shows how the chemical shift of xenon adsorbed on zeolite Na-Y, containing Pt particles deposited using the procedure of Gallezot et al. (401),... 

The Dow Chemical Company Dry Explosive Composition Containing Particulate Metal of Specific Mesh and Gauge... 

Guieu, C. et al. (1997) Atmospheric input of dissolved and particulate metals to the northwestern Mediterranean. Deep Sea Res., 44, 655-674. 

Rapin, F. and Forstner, U. (1983) Sequential leaching techniques for particulate metal speciation the selectivity of various extractants. In Proceedings of the 4th International Conference on Heavy Metals in the Environment, Vol. 2, Heidelberg, CEP Consultants, Edinburgh, pp. 1074-1077. 

The principal concern when using tires for fuel is the effect on emissions. Pollutants of particular concern include criteria pollutants, particulates, metals, and unburned organics. 

An emissions test of the pyro-gas was conducted at Conrad on December 18, 1986, while pyrolyzing TDF. Measurements included particulate, metals, volatile and semi-volatile organic compounds, sulfur dioxide (S02), nitrogen oxides (NOx), carbon dioxide (C02), oxygen (02), and carbon monoxide (CO).1 The test results are presented in Table 8-3. Note that these emission estimates do not reflect atmospheric emissions. 

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