Sediment types

The hydrocyclone, commonly referred to simply as cyclone, is a nonmechanical sedimentation-type classifier (2,6,10,27) (Fig. 7). It has no moving parts or power attachments directly connected to it. The hydrocyclone has become the workhorse of most mineral processing operations because of its simplicity, short residence time, compactness, and low cost of operation. It is, however, characterized by lack of sharpness of separation. Equipment... 

Sediment type %CaCO % clastic and clayey material % amorphous silica % pelagic sed. Composition... 

In figure 6 are presented some of the available 210Pb profiles in deep sea sediments. The data available to-date yield values ranging between (20-400) cm2/103 year for particle mixing coefficients, K [69]. The data also show that the mixing coefficients do not exhibit any systematic trend either with the sediment type or with sedimentation rate [69]. 

Sediment Type Wet Density x 103 (kg rrr3) % by Granular Particle Size (mm) Minimum-Mean-Maximum Organic Content (%)... 

The differences in the magnitudes of the parameters shown in Table 3.7 correspond well with the course of (anaerobic) microbial processes in the sewer deposits. Newly deposited sediments not only have the highest pollutant potential but also show the lowest critical shear stress for erosion. Such sediment types may exert the highest impacts on receiving waters from combined sewer overflows. 

Ellis et al. (2003) obtained an Sse(iv)-se(o) range for Se(lV) reduction of 5.5%o to 5.7%o in three experiments with two of the three sediment slurries used for the Se(Vl) reduction experiments reviewed above. Se(lV) concentrations were 100 pmol/L and 240 nmol/L for the estuarine sediment experiments and 460 nmol/L for the wetland sediment. As with the Se(Vl) reduction experiments from this study, there was no apparent dependence on Se concentration or sediment type, though the number of experiments was small. 

Figure 4. A schematic depiction of the Mo elemental budget in the modem oceans. Rough estimates of die percent removal to each sediment type, drawn from die literature, are indicated (see text).

Figure 9. A schematic depiction of the apparent Mo isotope budget in the modem oceans, neglecting suboxic sediments. Mean isotopic values for inputs and outputs are indicated, along with the fractional importance of each sediment type for Mo removal. See text for details.

While rapid burial enhances preservation, the type of sediment produced is determined by the relative particle composition of the deposit. For example, rapid burial of biogenic silicate by clay minerals helps protect the shells against dissolution, but the resulting deposit is classified as an abyssal clay, rather than a siliceous ooze, if the sediment is less than 30% by mass BSi. Thus, prediction of the sediment type likely to be found at a given location requires knowledge of the relative magnitudes of the accumulation rates of all particle types. 

Figure 20.1 illustrates that the major sediment type on the abyssal plains are the abyssal clays with some local exceptions, including equatorial radiolarian oozes, manganese nodifles, and metalliferous sediments. 

Sediment type Atlantic Pacific Indian World... 

The distribution of sediment types in the Pacific Ocean is much different from that of the Atlantic. Except for the coastline of the northwest United States, the Pacific is ringed by deep-sea trenches and, hence, has relatively narrow continental shelves. The trenches effectively trap all the terrigenous particles carried to the sea by river runoff. The Pacific Ocean is much wider than the other oceans thus the flux of wind-borne lithogenous particles is spread over a much greater area and produces a much lower mass flux, on an areal basis, to the seafloor. This makes other particles relatively important in determining the composition of the sediments in the Pacific ocean. 

Sediment Type Location Carbon Burial % of Total... 

Reinert, K.H. andRodgers, J.H., Jr. Influence of sediment types on the sorption of endothall. Bull. Environ. Contam. Toxicol, 32(5) 557-564, 1984. 

Versatile remediates a variety of mixed wastes and operates under varying ground conditions and sediment types. 

Though developed for sediments (can be applied to any sediment type), can be applied to other media (e.g., soils, water column). 

The SQT has been accepted internationally as the most comprehensive approach available for assessing contaminated sediments. It has been widely used, not just in North America, but in Europe, Australasia, South America, and the Antarctic. It is extremely cost-effective for the level of information provided when applied in a tiered and iterative fashion. It can be used with all sediment types and can be adapted for use with soils and the water column. It provides information on potential effects... 

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