Study On Purification Effect Of Constructed Wetland On Fuzhou River In Dalian

Water resources is one of the most basic resources for human survival,but also a strategic resource for national social and economic development.River as a carrier of water resources for China's future socio-economic development and ecological environment construction play a decisive role.But China's current sewage emissions far more than the river can withstand the capacity of the environment,and limited water resources are also gradually pollution damage.China's river pollution problem is more serious,river water pollution control is imminent.The constructed wetland technology,as a new type of sewage treatment technology,has the advantages of low running cost,convenient management and remarkable purification effect,so that it has extensive development and application prospect.Therefore,it is very important to study the effect of constructed wetland on the purification of polluted river water in China's ecological environment.First of all,according to the existing information on the constructed wetland in China,relying on the hydrological civilization construction project of Dalian City,the paper analyzes the types,bases,plants and combinations of wetland for the background of experimental sites and the experimental requirements Way,in the case of river water flow design constructed wetlands,making the constructed wetland system into and out of water completely rely on water gravity free flow.The constructed wetland system consists of 3 rows and 4 columns of 12 constructed wetland units.The four kinds of constructed wetlands are composed of three different types of wetlands in surface flow,horizontal flow and vertical flow.Secondly,the effect of constructed wetland on the pollution of river water was studied.In the experiment cycle,the water samples were taken in the natural environment and returned to the laboratory to detect COD,TN and TP.Through the analysis of the experimental data,the constructed wetlands and the wetland units were studied.The change of the concentration of the index and its removal rate,and analyze the effect and difference of the different combinations of the constructed wetland system under the same experimental conditions.The results showed that the removal quantity of COD and TN was the largest in combination 2(vertical-horizontal-surface flow wetlands),and the removal quantity of TP was the highest in combination 4(surface-vertical-horizontal flow wetlands).Vertical wetland and horizontal flow wetland have a great contribution to the removal of pollutants,while the removal of surface wetlands is relatively small.Finally,the influencing factors of the removal effect of constructed wetland were analyzed.Based on the analysis of the experimental data of COD,TN and TP,the effect of temperature change on the decontamination effect of constructed wetland was studied.The effects of different substrates and different plants on the effect of different types of constructed wetlands on the pollution of river water were studied.Technical support and application of wetland system for purification of sewage.The results showed that the effect of temperature on COD and TP removal rate was not significant,and the temperature had a great effect on TN removal rate of vertical wetland and horizontal flow wetland.The removal quantity of COD and TN in the gravel wetland is higher than that in the pebble wetland,and the removal quantity of TP in the gravel wetland is lower than that in the pebble wetland.The COD and TP removal quantity of reed wetland were less than those of yellow iris wetland,and the removal quantity of TN in reed wetland was close to that of yellow iris.