Operation and Upgrading the Capacity of Wastewater Treatment Plants by Activated Sludge Method Using the Mass Flux Approach (Case Study of Wastewater Treatment Plant of Shahrak Gharb in Tehran

Document Type : Case study


1 PhD Student in Engineering and Water Resources Management, Dept. of Civil Engineering, Roudehen Branch, Islamic Azad University, Roudehen, Iran

2 Assist. Prof., Dept. of Civil Engineering, Roudehen Branch, Islamic Azad University, Roudehen, Iran


One of the major challenges in the operation of wastewater treatment plants is the lack of experts and the lack of use of new methods in the management of this system, which has rarely been addressed in the past. Therefore, the application of new methods in exploitation is of great importance and in this regard, in the present study, using the mass flux approach, velocity and behavior of sediment particles and sludge masses in the secondary sedimentation pond by performing Settling column experiment with observance of the sludge index range between 150 and 250 mg/L, with the preparation of 6 different concentrations of raw wastewater, effluent and returned sludge continuously for more than 18 months (551 days) and in different climatic conditions were studied. By drawing graphs of height-time, concentration-velocity, concentration- mass flux, the relationships between important parameters were obtained using MATLAB software and new mathematical and experimental models that could estimate velocity in a wide range of different concentrations were presented and observed in unusual conditions. By determining the optimal operating point (sp), the capacity of wastewater treatment plants can be increased between 15 and 20% at no cost.


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