A three-dimensional numerical model is proposed for modeling the TP transport in the Horizontal Subsurface Flow (HSSF) and Wavy subsurface Flow (WSSF) constructed wetland in this article. Both numerical simulations and physical experiments indicate that the removal efficiency of WSSF is higher than that of HSSF. The difference of performance in removing pollutants, e.g., Total Phosphorus (TP), ...

The SWIFT2D surface-water flow and transport code, which solves the St Venant equations in two dimensions, was coupled with the SEAWAT variable-density ground-water code to represent hydrologic processes in coastal wetlands and adjacent estuaries. A sequentially coupled time-lagged approach was implemented, based on a variable-density form of Darcy’s Law, to couple the surface and subsurface sy...

introduction wetlands are classified into four kinds of flows as subsurface, surface, vertical, and hybrid flows. usually, wetlands are planted with common reed (phragmites australis), a rhizomatose plant of the graminae which produces a good yield in green biomass and whose roots can reach a considerable depth and plays a significant role in the wetland self-purification. the treatment efficie...

We monitored the water quality and hydrological conditions of a horizontal subsurface constructed wetland (HSSF-CW) in Beijing, China, for two years. We simulated the area-based constant and the temperature coefficient with the first-order kinetic model. We examined the relationships between the nitrogen (N) removal rate, N load, seasonal variations in the N removal rate, and environmental fact...

Constructed wetlands (CWs) are engineered water treatment systems designed to remove various types of contaminants. A large number of processes simultaneously contribute to water quality improvement in CWs. During the last decade, there has been a wide interest in the understanding of complex “constructed wetland” systems, including the development of numerical process-based models describing t...

Constructed wetlands (CWs) have proved to be a highly effective measure to reduce the ecological impact of combined sewer overflows (CSOs) on receiving waters. Due to the stochastic nature of the loading regime and the multitude of environmental influences, assessment of the performance of such plants requires detailed mathematical modelling. A multi-component reactive transport module (CW2D) w...

Municipal leachate was treated in an experimental unit of constructed wetlands of subsurface flow type. The parameters studied were organics (BOD and COD), solids and heavy metals (Zn, Ni, Cu, Cr and Pb). Using two types of emergent plants of Scirpus globulosus and Eriocaulon sexangulare, more than 80% removal was achieved for all the parameters. E. sexangulare removed organics and heavy metals...

In this study, five mixed substrates – SSFGF, FSSGF, FSSFF, FSSFG, and FSFGF – consisting of fly ash, sludge, soil, fine cinder, gravels, and fine sand, were made in order to test the removal effect of lead. Multiple comparisons and analysis of variance were used to analyze physicochemical properties and the removal efficiency of lead. The test results showed that for five substrates, the efflu...

Abstract The anaerobic process is considered to be a sustainable technology for the treatment of wastewaters rich in organic matter mainly due its lower energy consumption and production value-added products such as biogas fertilizer. However, it cannot seen providing ‘complete’ environmental solution treated effluents would typically not meet desired discharge limits terms residual carbon, nut...