Comparison of Water Purification Efficiency of Vertical and Horizontal Sand Filters in Drip Irrigation System

Due to the lack of highquality water resources, in many cases there is no other choice but to use lowquality or unconventional water. The filtration method is an efficient method for removing pollutants. For compare the amount of water purification in vertical and horizontal filters, two models of vertical and horizontal filters were made in Department of Irrigation and Development Engineering, University of Tehran.Three absorbent layers including sand, zeolite and rice husk were used. The purification rate was measured for three solutions contaminated with nitrate, salinity and TSS of each solution at two different concentrations. For each concentration of contamination, two purified samples were taken at two times of 5 and 10 minutes to determine the purification process over time. t-test was used in SPSS software to compare the filtration rate of vertical and horizontal filter and to observe the significance of the difference in filtration rates. The results showed that the amount of nitrate purification with concentrations of 36.72 and 59.08 mg/liter and at times of 5 and 10 minutes, respectively, in the vertical filter was 6.99, 9.25 and 7.72, 7.13% and in the horizontal filter was 3.18, 8.21 and 8.36, 5.70%. For EC, the filtration rate in two electrical conductivities is 31.6 and 11.02 dS/m and in two times for vertical filter 5.39, 2.54 and 5.26, 2.18% and horizontal filter 12. 4, 1.90 and 2.99, 1.54% were measured. The filtration rate of TSS for two solutions containing TSS with concentrations of 0.75 and 1.5 g/l and at two times were checked and the filtration rate of the vertical filter was 48.93, 43.87 and 73.20, 80.25% and the horizontal filter purification rate was 29.66, 38.40 and 61.31, 67.05%. Finally, the obtained results showed; There is no significant difference in nitrate, EC and TSS purification between vertical and horizontal filters.