Iranian Journal of

Background and Objectives:Dual media filters have two different layer beds consist of sand and Anthracite. Advantage of dual media filters is longer run duration and more filtration rate. The purpose of this study was to achieve a performable model to improve single media Filters in water treatment plants.
Materials and Methods: in this cross-sectional study, two pilots mono and dual media were made and in a 5 month period samples taking were done. Total samples taken from input and output of each pilot, was 40. The samples then introduced for the measurment of turbidity and total organic carbon. Meanwhile the filters head loss also quantified in 40 times head loss measurement was done.
Results: Average turbidity removal in mono and two layer pilots were 63 and 65 percent respectively. Average removal of Total Organic Carbon in mono and two media pilots were 40 and 66 percent respectively. Head loss in dual and single media pilots were 0 .68 and 1.15 m respectively.
Conclusion: Although average torbidity removal disparity between two pilots was not significant the amount of total organic carbon removed was considerable. Average head loss in single media pilot was more than dual media type. Ratio of UFRV in dual media to mono media filter was 51:30 it shows that filtration rate capacity will be improved up to70 percent by changing media type.

Backgrounds and Objectives: Improvement of water quality standards and inability of mono layer filters in producing such quality caused researchers attended to multi layer filters. Due to specific characteristics of anthracite and leca can improve removal of organic materials and Surface over flow rate. The aim of this research was evaluation performance of dual media filters (anthracite/leca) in removing of organic materials and turbidity from Ahvaz Water treatment plant
Materials and Methods: In this study two pilots built for investigation of mono layer filter and dual media filter performance. The researcher used sand in structure's media of mono layer filter and composition of anthracite, sand and leca in structure's media of dual media filter, respectively.  In this study single and dual layer filter pilot examined in term of organic matter and turbidity removal efficiency. 
Results: Results indicated that removal of organic matter by single layer filter (sand), dual media filter (anthracite,  and sand), dual media filter (leca and sand) was 7%,12%,4/2% respectively. And also Turbidity removal by single layer filter(sand), dual media filter (anthracite and sand), dual media filter (leca and sand) was also  69%, 80%, 74% respectively.
Conclusion: Results of this study showed that upgrading of Single layer to dual layer with anthracite and leca media can‘t show a significant affect in TOC removal.