Journal of American Science, 2010;6(12) http://www.americanscience.org Evaluate of Head Loss, Sediment Value and Iron Removal in Rapid Sand Filter Hossein Banejad 1 , Reza Pirtaj Hamedany 1 , Navab Daneshi 1 1. Department of Water Engineering, Faculty of Agriculture, Bu-Ali Sina University, Hamedan, Iran Hossein_banejad@yahoo.com Abstract: Quality and appropriate quantity of water is necessary for human kind to survive. Along with the technology development and increasing consumption of water resources, we are experiencing low qualities in the mentioned resources. Iron is the fixed element found in the crust of the earth. This metal found variously in water resources and industrial activities. Therefore, it needs to treat the water resources from these excessive amounts. Different methods have used for this reason but the most used method during recent years has been the absorption by economic absorbers such as sand. Rapid sand filters usually used in water treatment plants for water clarification. In this research, a single layer gravity rapid sand filter has used to reduce different concentrations of iron. sediment value and head loss arising from it specially oxidized iron sediments in filter media is simulated by using combination of Carman-Kozeny, Rose and Gregory models in different discharges of rapid sand filter. Results have shown that with increasing in discharge and decreasing in input iron concentration, arriving time to given head loss, is increasing. In addition, results demonstrated that with increasing in iron concentration in influent, removal efficiency is decreasing somewhat. Results of this research can applied in (1) appropriate design of rapid sand filter to iron removal, (2) prediction of rapid sand filter ability to iron removal and (3) estimation of arising head loss during filter work thus evaluating of time interval backwash. [Hossein Banejad, Reza Pirtaj Hamedany, Navab Daneshi. Evaluate of Head Loss, Sediment Value and Iron Removal in Rapid Sand Filter [Hossein Banejad, Reza Pirtaj Hamedany, Navab Daneshi. Evaluate of Head Loss, Sediment Value and Iron Removal in Rapid Sand Filter. Journal of American Science 2010;6(12):1218-1226]. (ISSN: 1545-1003). http://www.americanscience.org . Keywords: Sand filter, Iron concentration, Removal efficiency, Head loss. 1. Introduction 1.1. Iron content in water and its removal In the past few decades using of heavy metals lead to increasing the concentration of this metals in water supply and environment. Discharge increasing of heavy metal from wastewater, their poisonous identity, Detroit effect on water supply (Nuhoglu et al., 2003) and indegradable in environment has caused to their special importance (saxena et al., 2006). Considering the increasing of industrial activity and problems due to the existence of heavy metals, removal or reduction of their concentration for achieving the acceptable level before discharge in environment is essential. Iron is of the metals that found in many water supplies and they could be considerably troublesome. Soluble of iron is colorless but in exposure with air or known chemical materials convert to insoluble form and create the colors in water. Some of problems that create by high concentration of iron in water can refer to interfere in disinfection process, slime formation in piping, taste and color. Removal the metal ions of industrial wastewater has been achieved by ion exchange, membrane separation (Katsumata et al., 2003), evaporation (Mouflih et al., 2005) electrolysis, absorption processes and reverse osmosis (Sarioglu et al., 2005, Pehlivan, et al., 2006). Choosing the best method to water treatment depends on the concentration of heavy metals in the wastewater and the treatment expenses. Depositing has used extensively for removal of heavy metals due to low performance expenses. However, default of this method is production of high volume of sludge (Raju., 2003). On the other, hand absorption method such as ion exchange method in easy for removal of metals but ion exchanging resins are expensive (Katsumata el al., 2003, Aslam el al., 2004). Among the mentioned methods, we should look for a method that is economic and easily applicable for developing countries and can use efficiently. Adsorption method has suggested for removal of heavy metals because it is cheaper and more effective than other technologies (Pehlivan et al., 2006). A method for metal removal can be applied to industrial wastes without prior treatment using solid adsorbents such as sand and silica (Yabe et al., 2003). In recent years, liquid content iron filtration through granular media such as silica is very considerable (Aklil el al., 2004, Mouflih el al., 2005). Effluent iron concentration is an important water quality criterion used for the assessment of the performance of rapid sand filters, in addition to other criteria (Cakmakci et al., 2010). http://www.americanscience.org editor@americanscience.org 1218