RESUMO
Introduction: The development of an appropriate model for the quality control of an industrial wastewater treatment system can save the time as well as the cost
This study was performed to determine an appropriate model in order to predict the COD and TKN parameters by BOD[5] and NH4+ in the Meybod industrial estate waste water treatment plant [WWTP]
Methods: This descriptive - analytical study was performed on 120 samples of the influent and effluent of the industrial estate wastewater treatment plant in JahanAbad, Meybod, Yazd in 2015. The studied parameters were BOD[5], TKN, COD, and NH[+4]
After measuring, they were imported to SPSS and Excel software to determine the relationship between them and then the linear regression model of the statistical method was used
Results: The predictive results of COD values on the basis of BOD[5] in the regression model showed that the coefficient of determination was 0.88 and the correlation coefficient was 0.93 [p = 0.000] for this relationship. The prediction of TKN values on the basis of NH[+4] in the regression model showed that for this relationship the determination coefficient of TKN and NH[+4] influent parameters was 0.877 and the correlation coefficient was 0.93 [p = 0.000]
Conclusion: This study represented that using the linear regression model for predicting COD and TKN values through BOD[5] and NH[+4] was in close accordance with the laboratory data and can thus be applied when the Meybod industrial estate WWTP faces time limitations or sampling problems
RESUMO
Introduction: The objective of this study was, wastewater quality investigation and removal efficiency of contaminants from the wastewater tile factory by using coagulants includes ferric chloride, ferric sulfate and ferrous, aluminum sulfate and poly aluminum chloride in order to reuse it in the processing line
Methods: This is an applied study
With regard to shiftwork schedules of the factory, the composite samples of wasrewater in production line was obtained. Firstly, based on standard methods wastewater parameters were measured
In the next step by using the jar- test the effect of changing coagulants dosing [0.15, 0.2, 0.25, 0.3, 0.35g/L] and pH values [7,9,11] on the removal parameters of turbidity, EC, TSS, TS and COD was investigated. Finaly the effective . dose and optimal pH were selected and the best coagulant was determined
Results:The optimum PH of ferric chloride, ferric sulfate and ferrous that optimum was lias well as it was 7 for aluminum sulfate and poly aluminum chloride. The optimum concentration of iron-based coagulants and aluminum-based coagulants was 0.3 g/L and 0.25 g/L, respectively. Poly aluminum chloride with removal of 99.92%, 99.94%, 89.8 and 75% has the best removal efficiency for turbidity, TSS, TS and COD, respectively. In addition, in a lower dose aluminum sulfate, ferrous sulfate, ferric chloride and ferric sulfate had the best removal efficiency
Conclusion: Among the five studied coagulants, poly aluminum chloride, aluminum sulfate and ferrous sulfate had the most efficiency, respectively. Due to the high cost of aluminum chloride, it needs more accuracy to select the most suitable coagulant
RESUMO
Background: Investigating the performance of naturally operated treatment plants may be due to the fact that they cannot be operated as desired, or that they should be modified to achieve good performance e.g. for nutrients removal. The advantage of kinetic coefficient determination is that the model can be adjusted to fit data and then used for analyzing alternatives to improve the process. This study investigates the efficiency of subsurface artificial wetland and determines its kinetic coefficients for nutrient removal
Methods: The present study investigated the kinetics of biological reactions that occurred in subsurface wetland to remove wastewater nutrient. Samples were taken from 3 locations of wetlands for 6 months. The nutrient content was determined through measuring Total Kjehldahl Nitrogen [TKN], ammonium, nitrate, and phosphate values
Results: Average levels for TKN, ammonium, nitrate, and phosphate in effluent of control wetland were 41.15, 23.59, 1.735, and 6.43 mg/L, and in wetland with reeds were 28.91, 19.99, 1.49 and 5.63 mg/L, respectively. First-order, second-order, and Stover-Kincannon models were applied and analyzed using statistical parameters obtained from the models [U[max], K[B]]
Conclusion: The nutrients removal at Yazd wastewater treatment plant was remarkable, and the presence of reeds in wetland beds was not very efficient in improving system performance. Other more efficient plants are suggested to be evaluated in the system. Stover-Kincannon kinetic model provided predictions having the closest relationship with actual data obtained from the field