Remove Ridge

D. W. HoWid.2cy, A Eiterature Survey Methodsfor the Removal of Iodine Spedafrom Off-Gas andEiquid Waste Streams of Nuclear Power and Nuclear Fuel Reprocessing Plants, with Emphasis on Solid Sorbents, ORNL/TM-6350, Oak Ridge National Laboratory, Oak Ridge, Term., 1979. 

U.S. EPA, Mercuy and Arsenic Wastes Removal, Recovey, Treatment, and Disposal, Noyes Data Corp., Park Ridge, N.J., 1992. 

Fleming, J. L. (1989). Volatiliaation Technologies for Removing Organics from Water, Noyes Data Corp, Park Ridge, NJ. 

A solution, still controversial, has been recently proposed. This is the loss of sulfate from seawater during hydrothermal circulation through mid-ocean ridges (Edmond et al., 1979). The flow of water through these systems is estimated to be about 1.4 x 10 L/yr, about 0.4% of the flow of rivers. However, sulfate is quantitatively removed, yielding a flux of 125 Tg S/yr, capable of balancing the river flux. The controversy is whether the chemistry involved in removing sulfate is the formation of... 

The studies on the hydrothermal systems at midoceanic ridges during the last three decades clearly revealed that the seawater-basalt interaction at elevated temperatmes (ca. 100-400°C) affects the present-day seawater chemistry (Wolery and Sleep, 1976 Edmond et al., 1979 Humphris and Thompson, 1978). For example, a large quantity of Mg in seawater is taken from seawater interacting with midoceanic ridge basalt, whereas Ca, K, Rb, Li, Ba and Si are leached from basalt and are removed to seawater (Edmond et al., 1979 Von Dammet al., 1985a,b). 

The Mg content of hydrothermally altered volcanic rocks is reflected by the extent of seawater-volcanic rock interaction at elevated temperatures, because it has been experimentally and thermodynamically determined that nearly all of the Mg in seawater transfer to volcanic rocks, owing to the reaction of the cycled seawater with volcanic rocks at elevated temperatures (Bischoff and Dickson, 1975 Mottl and Holland, 1978 Wolery, 1979 Hajash and Chandler, 1981 Reed, 1983 Seyfried, 1987). It has been shown that the CaO content of hydrothermally altered midoceanic ridge basalt is inversely correlated with the MgO content with a slope of approximately — 1 on a molar basis (Mottl, 1983). This indicates that Ca of basalt is removed to seawater and Mg is taken up from seawater by the formation of chlorite and smectite during the seawater-basalt interaction. This type of reaction is simply written as ... 

Mg removal by seawater cycling through midoceanic ridges has been estimated by several workers. They vary widely and are —2.4 x 10 g/year (Mottl, 1983), —6.5 x 10 g/year (Wolery and Sleep, 1976), and —3.9 x 10 mol/year (Elderfield and Schultz, 1996). 

Kaiho and Saito (1994) estimated 20 x 10 km /m.y. and 2x 10 km /m.y. for present-day midoceanic ridge crustal production rate and back-arc basin crustal production rate, respectively. If their estimates are correct. Mg removal to midoceanic ridge basalt during early-middle Miocene age is estimated to be 2.6 1 x 10 g/year. Although estimates of annual Mg removal by interaction of circulating seawater with midoceanic ridge basalt are uncertain, it seems likely that Mg removal by seawater-volcanic rock interaction at back-arc basins corresponds to that of Mg removal at midoceanic ridge axis. 

Bowker, R. P. G. and Stensel, H. D., Phosphorus Removal from Wastewater, Noyes Data, Park Ridge, NJ, 1990,21. 

Fig. 11.5 Differential phase contrast detection of patterned protein in a 10 mm by 30 mm region, (a) Protein height signal showing ridges of protein in a checker board pattern, (b) Side band demodulated signal image in which the carrier frequency of the ridges is removed to show only the protein envelope. Reprinted from Ref. 21. with permission. 2008 Optical Society of America...

In such storage the water vapour is quickly removed by the wind and attack by rain is prevented. In more closed storage places, adequate ventilation must be provided via walls and roof-ridge, while large doors being required for removal of the manure. 

James et al. (1999) reported findings from ODP Site 1038 (Fig. 16b), adjacent to the Gorda Ridge, an area of active hydrothermal venting through a thick sedimentary pile. Pore fluids there had a range in isotopic compositions (8 Li = -0.6 to +27.5) that were modeled in terms of initial hydrothermal removal of Li from sediments followed by down-temperature fluid fractionation during crystallization of secondary minerals, and ultimately dilution with... 

Phosphate removal by sorption on Fe(lIIX)OH is particularly important in the vicinity of mid-ocean ridges and rises because hydrothermal activity supports a large flux of... 

Another application for adsorption of metal impurities is in the nuclear power industry. Radioactive cesium is one of the compounds that is difficult to remove from radioactive waste. This is because ordinary resins and zeolites do not effectively adsorb radioactive cesium. In 1997, lONSlV lE-911 crystalline silicotitan-ate (CST) ion exchangers were developed and effectively used to clean up radioactive wastes in the Melton Valley tanks at Oak Ridge [268, 269], CST was discovered [270] by researchers at Sandia National Laboratories and Texas A M University, with commercial manufacture carried out by UOP. 

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