A STOCHASTIC NUMERICAL APPROACH CONSIDERING UNCERTAIN-INPUT PARAMETERS FOR PHOSPHORUS REMOVAL IN CONSTRUCTED WETLANDS

A stochastic numerical approach for the operation problem con-cerning the removal of contaminants in Horizontal Subsurface Flow Constructed Wetlands (HSF CW) is presented. Emphasis is given to uncertain-but-bounded input-parameters, which are considered as interval parameters with known up-per and lower bounds. For the treatment of this uncertainty, the Monte Carlo method is used. The proposed methodology consists of applying the Monte Carlo procedure by solving the deterministic problem for each of the data -samples. Atypical case of a HSF CW unit, concerning Total Phosphorus (TP) removal, is used in a numerical example. The reliability of the proposed stochastic approach is proved by comparing the numerical results with avail-able experimental ones.