تقييم الأداء التشغيلي لمحطة معالجة مياه الصرف الصحي في كربلاء تحت معدلات جريان مختلفة باستخدام نموذج GPS-x

Evaluation of the Operational Performance of the Karbala Wastewater Treatment Plant under Various Flow Rates Using GPS-X Model

Abstract

Wastewater treatment plants (WWTPs) are functional systems with a variety of treatment procedures designed to remove or minimize wastewater harm. Today, a system integrating performance assessment methodologies and modern modeling tools is employed to help determine how effectively and suitably these plants should be operated. Wastewater generation in Karbala city, Iraq, has significantly increased as a result of urbanization and population growth, necessitating the effective functioning of wastewater treatment facilities. In the present GPS-X modeling software was used to model the wastewater treatment plant using five scenarios with different flow rates scenario 1 with influent flow of 40,000 m3/d, scenario 2 with influent flow of 60,000 m3/d, scenario 3 with influent flow of 100,000 m3/d , scenario 4 with influent flow of 140,000 m3/d and scenario 5 with influent flow of 180,000 m3/d to assess the operational effectiveness of the Karbala wastewater treatment plant (WWTP) in situations of variable flow rates.
The present study begins with a description of the Karbala WWTP’s design, capacity, treatment procedures, and infrastructure. The performance of will be examined, and the treatment processes will be simulated by using the GPS-X model. By using historical data from the plant, the model is calibrated and tested to assure accuracy. The quality of the influent raw wastewater and the effluent treated wastewater have been studied throughout the year 2022 (from 1/2022 to 12/2022) in order to evaluate wastewater treatment plants. The performance efficiency of the Karbala WWTP is assessed by using the biological oxygen demand (BOD5), chemical oxygen demand (COD), total suspended solids (TSS), ammonia-nitrogen (NH3+-N), orthophosphate (PO4-3), nitrate (NO3–N), and nitrite (NO2–N). Each parameter’s removal efficiency from the influent and effluent wastewater is determined, and then the results are compared to Iraqi specifications. The GPS-X (v.8) software was used to create the model of the plant.
The results of the calibration of the model show that the developed model can be used for future studies because the accuracy of the model was acceptable the correlation between actual and simulated data was ranged from 0.81 to 0.92. The root mean square error RMSE results was close to zero and range from 0.011 to 0.138 , and the results of the simulation were close to the real-world concentrations of the plant. The findings of the simulation and modeling of Karbala WWTP utilizing GPS-X indicated that the facility performed well with high effectiveness according to the output parameters. The number the of primary clarifier decreased from 4 to 2 and secondary clarifier decreased from 8 to 3 when the influent flow is 40,000 m3/d or less and the number of primary clarifiers decreased from 4 to 2 and the number of secondary clarifiers decreased from 8 to 4 when the influent flow to the treatment plant reach 60,000 m3/d that reduce the enegy and cost of operation.
The results of applying the five different scenarios showed that the values of the pollutants parameters TSS, COD, BOD5, NO2–N, NO3–N, NH3+-N, and PO4-3 in the effluent is remaining within acceptable limits of Iraqi standards and that the plant has high removal efficiency of pollutants with removal efficiencies ranged from 80 % to 94 % for TSS, from 83 % to 90 for COD , from 93 % to 96 % for BOD , from 86 % to 98 % for NH3+-N , and a the removal efficincy of PO4-3 is within limit .