Water treatment system overview

Glassmeyer, S. T., Kolpin, D. W., et al (2008) Environmental presence and persistence of pharmaceuticals - an overview. In Fate of Pharmaceuticals in the Environment and in Water Treatment Systems (ed. D. S. Aga) CRC Press-Taylor Francis Group, Boca Raton, Florida, pp. 3-51. 

In most of the gas/water/solvent systems ozonation was applied to model (waste) waters where the target substances were contained in the water phase, though examples of the treatment of pollutants contained in the solvent phase also do exist. The experiments were often conducted to study the working principles of such systems with their general goals (cf. Section B 6.3.1). Also some development of special types of reactors has been made. Table 6-3 gives an overview of the examples discussed. 

The discussion of existing processes of gas/water/solid systems is grouped according to the treatment goals. Table 6-4 gives an overview of the various systems studied in lab-scale or even applied in full-scale. 

This brief overview of separate treatment techniques is not complete, however it can be used for a first inventory and identification of treatment steps which may be considered as part of a complete closed loop water system. It has to be taken in mind that the above-mentioned overview of separate treatment techniques is primarily based on one type of pollutant and one physical state of that pollutant. It will be clear that very often the same treatment step can be applied to remove different types of pollutants. It is also evident that a large percentage of the separate treatment steps mentioned will result in a concentrate containing the pollutants. This concentrate has to be treated subsequently. 

The treatment of PAH-contaminated soil in a reactor environment is basically limited to the use of soil slurry reactors. Conversely, many different bioreactor designs exist for the treatment of water contaminated with PAHs. As reviewed by Grady (1989) and Grady Lim (1980), these include fixed film reactors, plug flow reactors, and a variety of gas-phase systems, to name a few. Given the depth and magnitude of such a topic, for the purposes of this review discussions will be limited to a generic overview of reactor applications for PAH bioremediation. 

A more or less clear overview of the enormous number of very different types of designs in fermentation, cell tissue culture, food, and waste water and waste treatment technology is possible. The designs cover technological application, the stirring and aeration system, and the phase of the main substrates. 

Ried, A., Mielcke, J., Wieland, A., et al (2007). An Overview of the Integration of Ozone Systems in Biological Treatment Steps, Water Science and Techn., 55, pp. 253-258. 

---