Organic overall total parameters

It should be recognized that the total volume of wastewater as well as the chemical analyses iadicating the organic and inorganic components are requited, backed by statistical validity, before the conceptualizing of the overall treatment plant design can begia. The basic parameters ia wastewater characterization are summarized ia Table 2. 

In several cases, such as shellfish areas and aquatic reserves, the usual water quaUty parameters do not apply because they are nonspecific as to detrimental effects on aquatic life. Eor example, COD is an overall measure of organic content, but it does not differentiate between toxic and nontoxic organics. In these cases, a species diversity index has been employed as related to either free-floating or benthic organisms. The index indicates the overall condition to the aquatic environment. It is related to the number of species in the sample. The higher the species diversity index, the more productive the aquatic system. The species diversity index is computed by the equation K- = (S — 1)/logjg I, where S is the number of species and /the total number of individual organisms counted. 

As mentioned earlier, TOC is another important water quality parameter. TOC is equal to the total concentration of organic carbon in water and is reported as milligrams carbon/liter (mg C/L). It serves as a general indicator of the overall quantity of carbon-based matter contained in water. TOC frequently correlates to BOD and COD but is not necessarily always a reliable measure. If a repeatable empirical relationship is established between TOC and BOD or TOC and COD for a particular wastewater, TOC can be used as an estimate of the corresponding BOD or COD. The theoretical TOC (ThCOD) can be calculated stoichiometricaly in similar manner to the ThCOD. 

Parameters such as biochemical oxygen demand (e.g. BOD5) and chemical oxygen demand (COD) cannot simply be converted into a figure for the total content of organic matter. For this reason, additional overall parameters have been introduced to establish the total content of organically bound... 

Thus different parts of the molecule may carry hydration shells that have significantly different properties. This leads to mutually destructive intramolecular overlap of water shells and the resulting overall hydration characteristics will definitely represent these complexities. This makes it difficult to define hydrophobic parameters for organic functional groups because they will depend on their position in the molecule. Only long alkyl functionalities do not suffer from these overlap effects. Recent kinetic studies have demonstrated these effects and rough estimates have been made of the extent of the overlap region in the total hydration shell vide supra). 

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