Influence of environmental factor on the performance of Pistia Stratiotes in a surface sequencing baffled steep flow constructed wetland

摘要

The performance of Pistia Stratiotes for organic matter and ammoniacal nitrogen removal was monitored in a surface sequencing baffled steep flow constructed wetland reactor at various intensity of sunlight. The reactor has 5 compartments of various sizes (C1-C5). Pistia Stratiotes were planted in all the compartments of the reactor. Influent wastewater was applied to compartment 1 (CI) at a hydraulic loading rate (HLR) of 10.2 m~3/m.d~(-1) and hydraulic retention time (HRT) of 6 hours. The average organic loading rate (OLR) and ammonia loading rate (ALR) were in the range 6-8 g COD/m~3.m.d ~1 and 0.15-0.25 g NH_4~+-N/m~3.m.d~(-1) respectively. Reactor temperature was daily monitored alongside sample collection at 9 AM, 12 PM, 3 PM and 7 PM respectively for 7 days. On day 4, (3 PM at 35.9°C), NH_4~+-N removal reached 94%. COD removal reached 50-55% between 9 AM and 12 PM but fluctuated between 5-14% at 7 PM from day 1 to day 7. This study demonstrates that temperature can influence the performance of Pistia Stratiotes.