Modeling of constructed wetland performance in BOD5 removal for domestic wastewater under changes in relative humidity using genetic programming.

Despite the extensive use of constructed wetland (CW) as an effective method for domestic wastewater treatment, there is lack of clarity in arriving at well-defined design guidelines. This is particularly due to the fact that the design of CW is dependent on many inter-connected parameters which interact in a complex manner. Consequently, different researchers in the past have tried to address different aspects of this complexity. In this study, an attempt is made to model the influence of relative humidity (RH) in the effectiveness of BOD5 removal. Since it is an accepted fact that plants respond to change in humidity, it is necessary to take this parameter into consideration particularly when the CW is to be designed involving changes in relative humidity over a shorter time horizon (say a couple of months). This study reveals that BOD5out depends on the ratio of BOD5in and relative humidity. An attempt is also made to model the outlet BOD5 using genetic programming with inlet BOD5 and relative humidity as input parameters.