Treatment matrix for reuse of upgraded wastewater

In 2003 the Aquarec project sponsored by the European Commission under the 5th Framework Programme was started, aiming at “integrated concepts for reuse of upgraded wastewater with special focus on the European countries”. One of the key elements is the development of a treatment matrix, in which wastewater treatment processes are categorised as a function of the raw wastewater quality and the reuse application and are further characterised with respect to costs, operational critical control points and environmental aspects. The construction of the treatment matrix is based on the reuse options (industrial, domestic, natural and agricultural applications), the water quality requirements, the treatment requirements and the extensive description of the various treatment processes and schemes. In the process of constructing the matrix it can be concluded that the actual knowledge on municipal wastewater treatment is definitely well consolidated until the so-called secondary treatment including biological or physical/chemical nutrients removal; the treatment of this effluent should be accomplished by more advanced techniques. As a consequence of the actual EU rules on water discharges, it makes sense to focus the Aquarec project on the possible refinements of secondary effluent. Great attention must be given to the advanced or tertiary wastewater treatment processes, as a mean to upgrade the effluent to water suitable for reuse.