Wastewater dissolved organic carbon

Along the same line, UV-vis based scanning for deviations from a blank reference in industrial wastewaters can indicate problems on an upstream level that remain undetected using conventional parameters. The so-called alarm parameters need not even be based on detailed interpretation of all absorption bands. In a coarse manner, absorption in certain spectral regions may correlate with lump parameters such as total organic carbon (TOC), dissolved organic carbon (DOC) and the like. ... 

Dissolved organic carbon (DOC) is another common component of natural waters. In secondary wastewater, the DOC concentration is sixfold higher than potable water, thereby requiring a larger dose of radiation due to its scavenging effect to achieve the required removal efficiency. Only indirect studies for the reaction of OH with DOC have been conducted, while scavenging of e and H by DOC has not been studied. 

Leenheer, J.A., Comprehensive approach to preparative isolation and fractionation of dissolved organic carbon from natural waters and wastewaters, Environ. Sci. Technol., 15, 578, 1981. 

Carbon type and dosage are crucial variables that affect the performance of the PAC-activated sludge process. Both variables are significant in predicting effluent dissolved organic carbon (DOC) as shown in Fig. 7 (15). While the shape of these curves is generally similar for different wastes and carbon types, the coordinates vary with each wastewater and should be determined in the laboratory. 

Figure 10.8 Refinery wastewater effluent C levels of total organic carbon (TOC), dissolved organic carbon (DOC) and oil and grease during incubation at 20°C (values are the averages for duplicate flasks).

Leenheer, J. A. (1981), Comprehensive Approach to Preparation, Isolation and Fractionation of Dissolved Organic Carbon from Natural Waters and Wastewaters, Environ. Sci. Technol. 15, 578-587. 

Figure 8. Evolution of COD value and UV spectra during BDOC determination of an urban wastewater sample (RDOC, refractory dissolved organic carbon).

Membranes are used for the treatment of contaminated aqueous solutions to produce water with a specific quality for different uses, including potable water and distilled water. Among the membrane processes, nanofiltration (NF) has been increasingly used for the treatment of wastewaters, such as natural organic matter (NOM) aqueous solutions. Humic acid (HA) is one of the common NOM that causes a major problem in surface water purification. HA is classified as a dissolved organic carbon (DOC) and has an impact on water color for concentrations above 5 mg/1 (Schafer et al. 2000). 

Coke furnace wastewater containing dissolved organic carbon (DOC) of 69 ppm and two peaks at the molecular weight of 400 and 10,000 Da was subjected to the filtration by the activated carbon membrane. Figure 9.20 displays (permeate concentration in chemical oxygen demand (COD)/feed concentration in COD=C/Co) versus effluent volume. Each curve indicates the typical breakthrough cirrve but interestingly the curve never exceeds (C/Co) ratio of 0.68, which means 32% of the COD is removed by the sieve mechanism. Hence, the COD removal by the... 

Weishaar, J.L., Aiken, G.R., Bergamaschi, B.A.,Eram, M.S., andPujii, R. (2003). Evaluation of specific ultra-violet absorbance as an indicator of the chemical composition and reactivity of dissolved organic carbon. Environ. Sci. Technol., 37,4702-4708. Westerhoff, R, Chem, W., and Esparza, M. (2001). Fluorescence analysis of a standard fulvic acid and tertiary treated wastewater. J. Environ. Qual., 30, 2037-2046. 

The wastewater produced in this process consists mostly of water used in cleanup and propellant conveyance and sorting operations. Techniques such as the use of activated carbon and biological treatment are being investigated for the removal of solvents and dissolved organic compounds (143). 

Granular activated carbon (GAC) and peat adsorption are two tertiary wastewater filtration processes using GAC and peat, respectively, as the media for removing not only insoluble suspended solids, but also dissolved organic solids.8 Tables 7.14 and 7.15 report the adsorption efficiencies for... 

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