Micro Pollution Of Drinking Water Bio-filtration Test

This article examines the application of biofiltration as final process for slightly-polluted water treatment to current problems of widely polluted source water. Biofiltration, possessing the advantage of removing organic matters and turbidity in the same filter, is an effective and economical technology.Further study has been conducted to evaluate the performance of biof iltration removing organic matters., NHT-N , Fe, Mn and turbidity through pilot-plant experiments. Furthermore, several factors considered affecting biofiltration process have been examined, they are: empty contact time(EBCT), water temperature, floes, backwash and shut down of biof ilters.The Results of experiment on biofiltration performance show that biof iltration can remove the organic matters, NH/-N, Fe, Mn as well as turbidity in the same filter effectively.When water temperature is 8C, filtration rate is 8m/h, the removal of assimilable organic carbon (AOC) , biologically degradable organic carbon(BDOC) in biofilters are 59.2%~84.2% and 4l.3%~65.0% separately, while GAOsand filter average . best removal, effluent AOC is less than 50 \i g/L, which can achieve biologically stable water better. Biofilters can also meet the requirement of effluent tubidity. When influent turbidity is bellow 5NTU, the effluent turbidity of biofiltration can maintain less than 0.1NTU for a long time.In the rage of 4. 5min~ 18min , increasing EBCT will improve the performance of biofilters but less than proportionally; biofiltration behave well in higher temperature;the accumulation of floes in biofilter maybe act as a diffusion barrier for biodegradable compounds, thus bring some disadvantage for biofiltration; backwash with nonchlorinated water has less impact on biofiltration; shutdown of biofilters cause little disadvantage, the biofilters can return to normal state in a short time.