The Effect of Antibiotics on Urban Wastewater Cod Assessment and Their Control by Magnetically Activated Carbon

Abstract

In this study, the effect of ten pharmaceutical micro pollutants from the categories of antibiotics drugs on the activated sludge process was studied. In order to express the extent of this undesirable effect, two indices, inhibition percentage and toxicity index, were calculated. The COD trend during the sludge process was considered as an evaluation factor.

In reactors containing 2 mg/L of each drug, it was observed that the COD removal rate was reduced by 49% compared to the control reactor. This impairment in COD removal varied depending on the type of drug.

Before evaluating the efficiency of this pretreatment method, the separation of activated carbon by two methods of coagulation, flocculation and magnetization was also evaluated.
To this end, by adding using magnetized activated carbon for pretreatment up to a concentration of 5000 mg/L, the inhibition COD removal rate for wastewater contaminated with 20 mg of the drug combination reaches 16%. Also, the optimal contact time for effective removal of drugs by magnetic activated carbon is 90 minutes. The results showed that the adverse effect of pharmaceutical pollutants in wastewater reactors containing 2 mg/L of all drugs when passing through the pretreatment stage COD is reduced by 71%.