ELIMINATION OF COD, MICROORGANISMS AND PHARMACEUTICALS FROM SEWAGE BY TRICKLING THROUGH SANDY SOIL BELOW LEAKING SEWERS

AN P. / HUA J. / WINTER J. / et al. - ARTICLE DE PERIODIQUE - 2003

To simulate the filtration and/or degradation of trickling sewage from leaky sewers through the non-water-saturated underground, sewage was trickled through sand of .4-2mm from the Rhine valley in glass columns of 125cm length. The COD removal efficiency varied from 65 to 79% for sewage from rain and dry periods, respectively. About 50% of an initial COD were filtrated off on top of the sand or degraded in the uppermost 25cm at varying trickling rates. Another 6-12% were removed in the following 25-50cm of sand. Total bacteria decreased faster with than that of total aerobic-anaerobic bacteria.