Wastewater effluent characterization

According to modem standards mineral fertilizers are partitioned into two groups standardized and non-standardized. The standardized fertilizers include nitrogen, phosphoms, potassium, complex, and micro-fertilizers that contain the nutrients at the standard basis. The non-standardized fertilizers are municipal wastewater effluents, municipal solid wastes, polluted river waters used for irrigation, etc., which are not characterized by standard content of nutrients. However one should add that in all fertilizers including standardized type there are the admixtures, which pollute the agrolandscape. The known examples are phosphoms fertilizers and any municipal waste and wastewater with a pool of heavy metals and various organic pollutants. 

A. Analysis of Wastewater and Natural Waters. The presence of certain anions in wastewater effluents can cause deterioration of natural water systems. Phosphorous and nitrogen can be present in several chemical forms in wastewaters. Phosphorous is usually present as phosphate, polyphosphate and organically-bound phosphorus. The nitrogen compounds of interest in wastewater characterization are ammonia, nitrite, nitrate and organic nitrogen. Analyses are often based on titrimetric, and colorimetric methods (3). These methods are time consuming and subject to a number of interferences. Ion Chromatography can be used to determine low ppm concentrations of these ions in less than thirty minutes with no sample preparation. 

Jolley, R. L. et al. Nonvolatile Organics in Disinfected Wastewater Effluents Chemical Characterization and Mutagenicity MERL. U.S. Environmental Protection Agency. U.S. Government Printing Office Washington, DC, 1982 EPA-600/2-82-017. 

Ma, H., Allen, H., and Yin, Y. (2001). Characterization of isolated fractions of dissolved organic matter from natural waters and a wastewater effluent. Water Res. 35, 985-996. 

When applied for characterizing the potential toxicity of wastewater effluents, the pT-method can draw attention to certain groups of chemicals in the effluent. In Section 5.7, for example, the extremely high pT-values measured with the luminescent bacteria test (pT value = 7) and the Daphnia test (pT value = 8) indicate that chemicals eliciting these toxic effects must subsequently be identified and removed in the wastewater treatment process, so as to protect decomposers and micro-crustaceans. 

Another important industrial sector investigated was the textile industry. Ten different effluent samples were collected and each wastewater was characterized by standard chemical analyses as well as by the toxicity test battery. In this case, the test species included Daphnia, Hydra and Lactuca. Toxicity endpoint values were first transformed into toxic units (TU), a quantitative expression reflecting the resulting toxic potential of all chemical contaminants present in an effluent sample. Subsequently, their PEEP values were determined (Tab. 13). 

In order to treat effluents characterized by metallic and organic pollutants, an association of two different adsorbents, sugar beet pulp and granular activated carbon, is investigated. In a first step, equilibrium data are determined for each adsorbent and mono-component solutions. Then, multi-metallic and oiganic-metal solutions are tested to determine some inhibitions or special selectivities. Finally, it is shown that the association of sugar beet pulp for metal removal, and activated carbon for organic elimination, is efficient to treat complex wastewaters. 

A comprehensive analytical program for characterising wastewaters should be based on relevance to unit treatment process operations, the poUutant or pollutants to be removed ia each, and effluent quality constraints. The qualitative and quantitative characteristics of waste streams to be treated not only serve as a basis for sising system processes within the facility, but also iadicate streams having refractory constituents, potential toxicants, or biostats. Such streams are not amenable to effective biological treatment, as iadicated by the characterization results, and requite treatment usiag alternative processes. 

Because of the processes carried out in the plant, the expected compounds in wastewater are formaldehyde, urea, and polymers of these compounds. The global effluent of this kind of factory is characterized by a high chemical oxygen demand (COD) (due mainly to formaldehyde), relatively high values of nitrogen (arising from urea and copolymers) and a low content of phosphorus and inorganic carbon. The main characteristics of the effluent of a resin factory are showed in Table 19.1. 

This treatment process employs the use of physical operations such as screening and sedimentation to partially remove suspended solids and organic matter from the wastewater. This process provides the secondary treatment with wastewater that is partially free of solids, in order to facilitate further treatment. The effluent from the primary treatment contains primarily organic matter and is characterized by a relatively high biochemical oxygen demand (BOD).2... 

With the rapid increase in the nnmber of chemical industries, a great deal of waste-water is produced, which causes pollution and degrades the enviromnent. Many of these industrial wastewaters, particularly the ones, containing phenohc compounds, are well known to be characterized by higher salinity, acidity, chemical oxygen demand (COD) value and low biodegradability, which means that the effluent carmot be treated by the corrventional process [2, 3]. An alternative method of treating such... 

Prado T, Silva DM, Guilayn WC, Rose TL, Gaspar AMC, Miagostovich MP (2011) Quantification and molecular characterization of enteric viruses detected in effluents from two hospital wastewater treatment plants. Water Res 45 1287-1297... 

Spanggord RJ, Gibson BW, Keck RG, et al. 1982a. Effluent analysis of wastewater generated in the manufacture of 2,4,6-trinitrotoluene Characterization study. Environmental Science and Technology 16 229-232. 

Imai, A., Fukushima, T., Matsushige, K., Kim, Y.-H., and Choi, K. (2002). Characterization of dissolved organic matter in effluents from wastewater treatment plants 2002. Water Res. 36, 859-870. 

As seen further on in this chapter, individual PEEP index values express a condensed portrait of an effluent s hazard potential which takes into account several important ecotoxicological notions (toxic intensity and scope in terms of biotic levels impacted, bioavailability, persistence of toxicity and effluent flow). Unlike wastewater investigations limited to chemical characterization, this bioassay-based scale reflects the integrated responses of several representative toxicity tests to all interaction phenomena (antagonistic, additive and/or synergistic effects) that can be present in effluent samples. 

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