Study of Pollutant Reduction From Fish Farms Using Filtration (Case Study: Sardab River)

The waste water of fish farm contains suspended solids and soluble material that are discharged into the waters of downstream. This study evaluates the construction of a filter for reducing this pollutant. Therefore, the output water of farm after passing the rotatory filter (primary), enters to secondary filter (fixed); then passes from materials such as Geotextile, agricultural waste and zeolite. Soluble materials are also somewhat absorbed to these materials. In order to evaluate the capability of the device for absorbing suspended solids and soluble in water, the mentioned device has been installed on the output of the farms in the province and water quality sampling was conducted of input and output of devices. In all measured parameters from input and output of water in two stations of fish farm, concentration of parameters at 1 and 5 percent of probability level has significant difference, which is indicative of adverse effects of fish farms on the water quality. Moreover the results, in conducted investigation for reducing suspended solids (TSS) of output water of fish farms by filtration device, show that pollutants such as suspended solids are reduced by 97.48% with 30 L/S discharge which is desired amount and necessary for outlet of output .Also, filtration devices with several compounds, including monolayer Geotextile, agricultural waste and zeolite was used to reduce the parameters such as nitrate and phosphate from farms. The results were absorption of nitrate and phosphate after 24 hours that were reported, 38.3 and 37.86 respectively.