Efficiency of The Subsurface Flow Constructed Wetland in Ammonia Nitrogen And Phosphorus Removal from Synthetic Based on Domestic Wastewater in Lab Scale

Constructed wetlands (CWS) are mimic filtration process in natural wetlands that effectively remove variety pollutants from wastewater. The main objective was the feasibility evaluation for using of subsurface flow constructed wetland in nitrogen and phosphorus removal from synthetic based on domestic wastewater in lab scale. In this study، a synthetic wetland subsurface with horizontal flow was constructed in lab scale. Hydraulic retention time was 6 days and wastewater flow was gravity and continuous. Synthetic wastewater similar to domestic wastewater was used as influent inputs. COD/N/P ratio was considered 100/32/2. Material used in media stratification included charcoal، peat، course، and soil for proper plant growth، and according to the specifications the media slope and porosity range was 2% and 30-40% respectively. System depth was selected 0. 7 meter with regard to the design depth of phragmites. The purification flow rate was estimated with Darcy’s equation for porous layers as 50 liters per day. Cattail and common reed (phragmites) were planted in the constructed wetland. The indicated that the efficiency of subsurface CWs reactor with paired two tests and significance of 95% for Ammonia and total phosphorus removal were 35. 06 and 31% respectively (P < 0. 05). Maximum and minimum total suspended solids in effluent varied between 37 and 20 mg/l respectively. The efficiency of subsurface flow CWs reactor with gravel and peat media and using cattail and common reed (phragmites) plants for ammonia nitrogen and Phosphorous removals were appropriate and it can be an eco-friendly alternative which provides suitable operation and maintenance condition، instead of other mechanical systems for wastewater treatment.