Evaluation of Treatment Schemes Appropriate for Wastewater Reuse in Greece

The scope of this paper is the evaluation of wastewater reuse quality criteria and treatment specifications,
appropriate to Greek conditions. The parameters that affect wastewater reuse criteria were taken
into consideration, concerning among others reuse priorities, available treatment plants and effluent
characteristics. The proposed wastewater reclamation criteria were verified by a series of lab-scale
experiments, designed to study the feasibility and effectiveness of the following treatment schemes to
produce treated wastewater suitable for reuse: a) disinfection of secondary effluent with UV radiation
and chlorination and b) tertiary treatment and disinfection of wastewater with UV radiation and chlorination.
The experimental data were analyzed using a stochastic statistical model that employs Monte
Carlo simulation. The main scope of the stochastic approach was the regeneration of a greater set of
data, based on the defined by the experimental information mathematical distribution of each parameter
involved and the determination of relative probability distributions. Following this approach the
standards proposed are realistic and feasible and in the case of restricted reuse can be readily achieved
by the existing wastewater treatment plants in Greece. Even in the case of unrestricted reuse the additional
treatment required can be achieved at a moderate cost, through upgrading of the existing plants
with tertiary treatment.