Comparing the performance of wastewater treatment using activated sludge and aerated lagoons processes in the removal efficiency of estradiol hormones

Introduction: Due to the risks of hormones on human health and aquatic life, the aims of this study were to determine the efficiency of estrogen removal in the different stages of Shiraz wastewater treatment plant using activated sludge process and Marvdasht wastewater treatment plant using aerated lagoons process and also comparing the performance of both systems in removing the hormone of estrogen. Methods and Materials: In this study, the instantaneous sampling was used to take a sample from the wastewater treatment plants. The sampling was done for 3 times to determine the removal efficiency of estrogen hormone E2. The samples were transported to the laboratory within the maximum period of 3 hours. The Enhanced Chemiluminescence(ECL) was used to measure the hormone. The device (Elecsy 2010) was made by co-production tech companies (Roche) Germany and (Hitachi) Japan. Results: The results showed that the amount of estrogen in the influent wastewater treatment plants is approximately 40 pgmL-1.The percent of the removal of the hormone in Marvdasht wastewater treatment plant using lagoon aeration process was 52.5%. The hormone removal efficiency in Shiraz wastewater treatment plant using activated sludge was more than 82%. Primary sedimentation removes only 3 to 4 percent of theestradiol hormone. Conclusions: Although the primary wastewater treatment plant was able to remove a trace amount of estrogen, biological treatments plant has an important role in removing the hormone. The capability of activated sludge process in removing estrogen is higher than aerated lagoon.