Total organic carbon , river water

The esterification by-product, water, is removed via a process column in a continuous steady-state mode of operation. The bottom product of the column, being mainly EG, flows back into the esterification reactor. The condensed top product consists mainly of water with small traces of EG. In cases where a reverse-osmosis unit is connected to the distillate flow line, the residual EG can be separated very efficiently from the water [124], The combination of a process column with reverse osmosis saves energy cost and capital investment. The total organic carbon (TOC) value of the permeate is sufficiently low to allow its discharge into a river or the sea without any environmental impact. 

There is a scarcity of Canadian data on ground water quality. In 1979, a survey was undertaken by the Department of National Health and Welfare. Water samples were taken at 30 water treatment plants in 29 municipalities serving 5.5 million consumers, including all major population centers (11). Only three of these were ground water sources where minimal or no treatment was practiced. The total organic carbon content of these ground waters was less than half of that found in water supplies taken from rivers and lakes, and the trihalomethane content was also significantly low. 

River and lake water Total organic carbon TOC 64-67... 

Siepak, J. 1999. Total organic carbon (TOC) as a sum parameter of water pollution in selected Polish rivers (Vistula, Odra, and Warta). Acta Hydrochim. Hydrobiol. 27 282-285. 

Brazos River water contains a relatively high concentration of total organic carbon (TOC) in the summer. Some of this carbon is removed in the floe as indicated by both the CCE (Carbon Chloroform Extract) and TOC. 

Table 1 Database oftrace element concentration in the dissolved load (<0.2 xm) of rivers. All concentrations inppb (p-gL )except forRa(fgL and Os (pgL ). DOC, TSS, TDS are Dissolved Organic Carbon (mgL ), total suspended solid (mgL ), and total dissolved solutes (mgL ). Water discharge and surface are in s and 10 Km, respectively. 

Nevertheless, it seems reasonable to infer that aquatic humic substance concentrations in estuaries are intermediate between those of rivers and those of the open ocean, as would be expected from a mixture of river water and seawater. The concentrations of humic acids at intermediate salinities do not correspond, in a linear fashion, to the relative proportions of river water and seawater (Fig. 2), primarily because of a removal from solution of a portion of the riverine contribution. This behavior is in contrast to that of total dissolved organic carbon (DOC) which generally does show linear mixing lines when plotted versus salinity (Sholkovitz et al., 1978 Moore et al., 1979 Laane, 1980 Fox, 1983a Mantoura and Woodward, 1983). 

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