upgrading of tafresh municipal wastewater treatment plant (tmwtp) using the modified ludzack-ettinger (mle) process

The present study aimed to evaluate the treatment efficiency of the modified ludzack-ettinger (mle) process using the conventional activated sludge (cas) in tafresh city, located in iran during october- december 2016 (before upgrading) and october-december 2017 (after upgrading to the mle process). the measured parameters in the study included chemical oxygen demand (cod), five-day biochemical oxygen demand (bod5), nitrate-nitrogen, total suspended solids, phosphate, dissolved oxygen, ammonium-nitrogen, and ph. according to the obtained results, the treatment efficiency of the mle process based on the bod5 and cod was 92.11% and 91.20%, respectively. on the other hand, the treatment efficiency of the cas process (before upgrading) based on the bod5 and cod removal was 48.55% and 56.76%, respectively. therefore, it could be concluded that the mle process was able to successfully upgrade wastewater treatment services.