Vertical Sub-Flow Steel Slag Constructed Wetland Treating Domestic Sewage Containning High Concentration Ammonia Nitrogen

Constructed wetland is an economic, high effective and practicable technology treating sewage. Through technics improved, it can purify various contamination fully.Making COD, NH3-N, TN, PC43-P and TP as the monitoring objective, the author of this paper study the performance of steel slag adsorbing ammonia nitrogen and the longtime degradation effect of intermittent running steel slag-limestone vertical flow constructed wetland treating the wastewater containning high nitrogen. At the same time different factors experiments impacting treatment effect were opereated, such as intermittent inflow time, mixed progressively-sized and anti-sized bed and pure progressively-sized bed, surface filling, plant, four seasons, second-order series craft and so on. The mechnism removing pollutants by different parts of steel slag-limestone VFCW was analyzed, and the reaction kinetic models of purifing pollutants were established. In addition, clogging problems caused by different bed structure and improving running conditions assuring outflow quality were researched in experiment.The results indicate that the steel slag-limestone vertical flow constructed wetland containning mixed progressively-sized and anti-sized bed is a high effectiveness and longevity wetland type.