University of Tehran Press Iranian Journal of Soil and Water Research 2008-479X 47 1 2016 04 20 investigating the effects of environmental and hydraulic factors on phosphorus removal of agricultural waste using limestone investigating the effects of environmental and hydraulic factors on phosphorus removal of agricultural waste using limestone 65 74 57979 10.22059/ijswr.2016.57979 FA Fereshteh Zadjanali Choubari Maryam Navabian 0000-0001-7254-4312 Majid Vazife Doust Mehdi Esmaeili Varaki Journal Article 2014 08 13 With regard to the increase in population rate and the acute water shortages within recent years, reuse of agricultural waste water has been considered as an approach to the solution. Phosphorus is one of the pollutants of the agricultural waste water, the too excess mount of which causes the degradation of aquatic ecosystems, reducing the quality of water resources and eutrophication.. In the present study, the trend of phosphorus removal through limestone and the effect of some such factors as particle size, temperature, and pH on phosphorus removal as well as the effect of hydraulics of flow on the adsorption isotherm were studied. In this respect, the absorption kinetics experiments on limestone mining Langmuir and Freundlich adsorption isotherm equation as based upon laboratory scale and physical model of drain channel were performed at the University of Guilan in dimensions of 15×15×200 cm to investigate the effect of hydraulic flow drainage in two rates (0.05-0.1 Lit/s) on the adsorption isotherm. Kinetic experiments indicated that the rate of phosphorus removal through limestone was fixed after 30 hours. Between two size-ranges of limestone (0.5-1 and 3-5 mm), there was no significant difference observed in the percentage of phosphorus removal. The changes of pH showed that rate of phosphorus removal decreases in pH ranging from 2 to 6 while it increased in the pH range from 6 to 11. The optimal pH for phosphorus removal through limestone was obtained in alkaline conditions. Increasing the temperature from 22 to 30°C was followed by a downward trend of phosphorus removal. With regard to isotherm experiments, the Freundlich equation, as through limestone, showed close agreement. Within the physical model of the drainage canal, lower flow rates; showed better results regarding the extent of phosphorus elimination. A statistical comparison of adsorption isotherm (under controlled conditions in laboratory) and the physical model of drainage canal, the experimental results showed a statistically significant level of phosphor us removal and while not being fully satisfied with this result when planning for the design of phosphor us removal basins . With regard to the increase in population rate and the acute water shortages within recent years, reuse of agricultural waste water has been considered as an approach to the solution. Phosphorus is one of the pollutants of the agricultural waste water, the too excess mount of which causes the degradation of aquatic ecosystems, reducing the quality of water resources and eutrophication.. In the present study, the trend of phosphorus removal through limestone and the effect of some such factors as particle size, temperature, and pH on phosphorus removal as well as the effect of hydraulics of flow on the adsorption isotherm were studied. In this respect, the absorption kinetics experiments on limestone mining Langmuir and Freundlich adsorption isotherm equation as based upon laboratory scale and physical model of drain channel were performed at the University of Guilan in dimensions of 15×15×200 cm to investigate the effect of hydraulic flow drainage in two rates (0.05-0.1 Lit/s) on the adsorption isotherm. Kinetic experiments indicated that the rate of phosphorus removal through limestone was fixed after 30 hours. Between two size-ranges of limestone (0.5-1 and 3-5 mm), there was no significant difference observed in the percentage of phosphorus removal. The changes of pH showed that rate of phosphorus removal decreases in pH ranging from 2 to 6 while it increased in the pH range from 6 to 11. The optimal pH for phosphorus removal through limestone was obtained in alkaline conditions. Increasing the temperature from 22 to 30°C was followed by a downward trend of phosphorus removal. With regard to isotherm experiments, the Freundlich equation, as through limestone, showed close agreement. Within the physical model of the drainage canal, lower flow rates; showed better results regarding the extent of phosphorus elimination. A statistical comparison of adsorption isotherm (under controlled conditions in laboratory) and the physical model of drainage canal, the experimental results showed a statistically significant level of phosphor us removal and while not being fully satisfied with this result when planning for the design of phosphor us removal basins . https://ijswr.ut.ac.ir/article_57979_08db424cf22cef0afa6e99268c16a29c.pdf