Study On Purification Effect Of Several Wetland Plants On Domestic Sewage

Domestic and foreign scholars have done a lot of research on the mechanism and treatment of domestic sewage treatment of artificial wetland.The results show that in the constructed wetland treatment system,different aquatic plants will produce different purification effects when treating domestic sewage.According to the results of this study,this study used the static hydroponic method to study the common Reed（LW）、Arundo donax（LZ）、Panicum virgatum（LZJ）、Philodendroncv Xanadu（XTS）、Lysimachia christinae Hance（TQC）、Epipremnum aureum（LL）、Acorus calamus（CP）,7 kinds of aquatic plants such as calamus（CP）（2-3 strains/barrel）,static hydroponics,sterilization+hydroponics,hydroponics+diatomaceous earth adsorbent treatment of domestic sewage（6 L）,its research The results are as follows:（1）After 30 days of domestic sewage treatment by static hydroponic technology,it was found that the selected 7 aquatic plants have obvious purification effects on domestic sewage.Among them,XTS has the best purification effect on COD and BOD₅,and the removal rate is77%and 76%;LZ has the best purification effect on TN and TP,the removal rate is 73%and60%;LZJ has the best purification effect on NH₃-N,the removal rate is 71%;LW purifies NO₃-N The best results,the removal rate is 58%.（2）After the domestic sewage is sterilized and cooled for 30 days,the best purification effect on COD and BOD₅ is XTS,the removal rate is 75%and 66%;the removal rate of LZ to TN and TP is 65%and 60%.LZJ has the best purification effect on NH₃-N,and the removal rate is 45%;LW has the best purification effect on NO₃-N,and the removal rate is 54%.Compared with the conclusion（1）,the removal rate of COD、BOD₅、TN、TP、NH₃-N and NO₃-N by 7 plants was lower than that of non-sterilized after domestic sewage was sterilized+static hydroponics.Treatment indicates that microorganisms will have a certain degradation effect on domestic sewage.（3）In order to further purify domestic sewage,diatomaceous earth adsorbent（1 g）was used to deeply adsorb domestic sewage（100 mL）.After adsorption,the TN content of the 7plant groups decreased from 22.87-33.47 mg/L to 10.37-14.06 mg/L;the TP content decreased from 5.61-6.52 mg/L to 2.08-2.41 mg/L;NH₃-N content Reduced from 12.25-17.43 mg/L to5.64-7.42 mg/L;NO₃-N content decreased from 6.22-13.20 mg/L to 2.86-7.30 mg/L;COD content decreased from 84.07-144.41 mg/L to 51.28-76.59 mg/L;BOD₅ content decreased from 50.96-56.49 mg/L to 29.56-32.76 mg/L.In summary:three methods of static hydroponics,sterilization+hydroponics,hydroponics+diatomaceous earth adsorbent are used to treat domestic sewage,such as COD,BOD₅,TN,TP,NH₃-N and NO₃-N in sewage.The best removal effect of the six indicators was hydroponic+adsorbent,and the COD,BOD₅,TN and NH₃-N in the wastewater after the removal reached the secondary standard of the second pollutant discharge in the Yellow River Basin（Shaanxi Section）.