Elahe Khayyami; Mahdi Pahlevani; Ebrahim Esmailzadeh
Abstract
Background and purpose:This study aimed to evaluate the performance of biological process treatment (Modified Ludzack Ettinger) of municipal wastewater treatment plant No. 4 in Mashhad- Alteymur.Materials and methods: The performance of treatment plant was evaluated in a 12-month period from March 2020 ...
Read More
Background and purpose:This study aimed to evaluate the performance of biological process treatment (Modified Ludzack Ettinger) of municipal wastewater treatment plant No. 4 in Mashhad- Alteymur.Materials and methods: The performance of treatment plant was evaluated in a 12-month period from March 2020 to February 2021. Based on flow changes, a sampling of raw sewage inlet and outlet effluent was done in combination. Moreover, studied parameters, including BOD5, COD, TSS, TDS, EC, pH, total coliform, and fecal coliform were measured according to the methods presented in the standard method book for water and wastewater tests. ANOVA test was used to analyze the data and compare them.Results: Based on the results, the highest removal efficiencies are related to the parameters of T.C, FC, TSS, BOD5, COD, TDS, and EC, respectively, with 100, 100, 98.48, 97.88, 48.96, 25.97, and 25.88 percent, respectively. The significant removal efficiency of measured parameters in the effluent from wastewater treatment plant No. 4 of Mashhad (Altimour) shows the proper performance of MLE process system. The results of the ANOVA test to compare the removal efficiency of parameters in different seasons showed that the performance of treatment plant was not affected by the change of seasons.Conclusion: The amounts of pollutants were compared with the standard of the Environmental Protection Organization of Iran for discharge to the environment and using the wastewater. According to the studies performed on the tested parameters, the effluent is in line with the standards of the Environmental Protection Organization for irrigation and agriculture, surface water, and absorption wells, but for other uses and proper efficiency of the effluent, all aspects should be considered.
Mitra Mohammadi; Sepideh Ansari; Zeinab Asghari; Samaneh Najafi; Zohreh Mirzaei Niko; Elahe Khayyami
Abstract
Background and purpose: Vegetables are among the valuable foods. However, in addition to essential elements, they may contain toxins in excess of permissible concentrations, which has raised many concerns about the quality and safety of these products and human health. Therefore, the present study was ...
Read More
Background and purpose: Vegetables are among the valuable foods. However, in addition to essential elements, they may contain toxins in excess of permissible concentrations, which has raised many concerns about the quality and safety of these products and human health. Therefore, the present study was conducted to investigate the effect of atmospheric pollutants of carbon dioxide, gasoline and acid rain on the resistance of basil and parsley.Materials and Methods: This factorial study was performed based on a completely randomized design with 3 replications and 54 treatments . In this study, CO2 with three concentrations of 0, 1000 and, 1800 ppm, gasoline with three conditions without adding gasoline, with ordinary gasoline and with the addition of super gasoline, and acidic solution at two levels of pH 4 and 6 were studied. It should be noted that distilled water with pH = 7 was selected as a control treatment.Results: The results showed that the concentration of 1000 ppm carbon dioxide increased plant yield by 178.63%, while its concentration up to 1800 ppm, led to the destruction of the plant in two days. It was also found that super gasoline due to the high-octane number and supplements in it has a less polluting effect (5.7%) on the plant than regular gasoline. In addition, no significant difference was observed between different concentrations of acidic solution on plant resistance. In this experiment, parsley showed more resistance to contaminants than basil.Conclusion: carbon dioxide than other pollutants and also its key role in global warming, we need effective management to promote public health and control the production sources of this gas in the atmosphere.