Upgrading of Tafresh municipal wastewater treatment plant (TMWTP) using the Modified Ludzack-Ettinger (MLE) process

Document Type : Original Article


1 Department of Civil Engineering, University College of Omran-Toseeh, Hamedan, Iran

2 Department of Civil Engineering, Islamic Azad University, Hamedan Branch, Iran

3 Department of Environmental Science, Islamic Azad University, Hamedan Branch, Iran


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.


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