Transformation processes in water treatment plants and water distribution systems

A wide range of biotic and abiotic transformation processes are going on in treatment plants for groundwater and in the water distribution network. Recently it has become particulary interesting whether organic chemical pollutants in trace concentrations (ug/l) can be degraded. Preliminary experiments with aromatic hydrocarbons in a pilot water works, have shown that very high treatment efficiencies can be obtained resulting in residual concentrations of benzene, toluene, and naphthalene below 1 microg/l. This has to be further verified in larger scale, and a possible negative effect of iron precipitation has to be investigated. The transformation capacity of aromatics in the water distribution system is another interesting topic. It is planned to include a broader range of organic contaminants in the studies, including chlorinated aliphatic hydrocarbons and pesticides.
Biological transformation of some of the "traditional" pollutants is still an interesting research topic (nitrification, iron and manganese removal, etc.), in particular interactions between the specific groups of organisms involved.
Modelling of the organic and inorganic substrate removal and the simultaneous microbial growth and precipitation reactions is also considered as important. The better understanding of the process and the development of mathematical tools will improve the chances of success of the modelling.