Purification efficiency of different aquatic macrophytes wetland in high-salinity industrial wastewater
高盐工业废水人工湿地处理中植物的筛选

Petroleum and fine chemical industrial wastewater,treated by biochemical process with a high salinity,low nutrient content and high COD concentration can be further treated by constructed wetland for reuse.The aim of this study is to determine appropriate feed water salinity of constructed wetland,providing criteria for effective removal of organic pollutants in high-salinity wastewater.Through experiment on pilot-scaled constructed wetlands,effect of organic removals in this wastewater by different vegetations systems such as Phragmites communis,Scirpus tabernaemontani,Nymphaea tetragona ect were investigated,respectively.The relationship between COD removal and salinity of wastewater under the different plants growth was studied;and the impact of various salinity of waste water on species growth was discussed.The results indicate that,pollutant removal effeciancies by Phragmites communis,Nymphaea tetragona and Typha angustifolia system are better than that of Scirpus tabernaemontani and Typha latifolia system: the removal rate of COD,BOD and TP by the first three plants systems is about 38%,55% and 62%,while the removal rate of COD,BOD and TP for the rest two plants systems is about 30%,36% and 52% respectively;removal rate of TN by all the sysytems is above 85%.The relationship between chloride concentration and COD concentration of constructed wetland are various at different stages of plants growth.There is no significant correlation between them at the initial stage of plants growth,but positive correlation is shown in the following stages of plants growth.Therefore,salinity of the inlet should be adjusted according to plant growth stage in the constructed wetland.