HYDRODYNAMIC ASPECTS OF PARTICLE CLOGGING IN THE SIMULATED VERTICAL FLOW CONSTRUCTED WETLAND USING RIVER SANDS AS SUBSTRATE

This paper introduced a simple method for evaluating and predicting the degree of clogging in simulated Vertical Flow Constructed Wetland (VFCW) based on hydraulic conductivity (k) measurement. This method was developed for better understanding of the deposition by the changes of k and the captured particles capacity in substrate void relation with both time and depth in the simulated VFCW filter bed. Additionally, in order to gain an insight into the clogging, the study put forward a VFCW hydraulic conductivity formula and then calculated the accumulated particles in filter bed according to two calculated approaches. The results showed that the most clogged location was the top layer (0-10 cm), the development of head loss in the VFCW was strongly correlated with the surface area of the captured particles from influent, the maximum change of the porosity occurred in the initial operation period, and the clogging process was progressed step by step. The paper reported the results of captured particles in filter bed void and presented an equation to calculate the predicting clogging time in VFCW.