سیدعبداللطیف هاشمی فرد

The purpose of this study is to reuse greywater and prevent it from being released into the environment. In order to reduce the COD to the standard value, the combined method of membrane and advanced oxidation was used. Ten types of membrane samples with different concentrations of kaolin, alumina and calcium carbonate were prepared at a temperature of 1250(°C). The results of TGA, porosity and shrinkage analysis exhibited the decomposition of calcium carbonate at 800 (°C). The porosity and the average pore size of the membrane increased with the increase of calcium carbonate, so that by adding 5, 10 and 15% of calcium carbonate to the mullite membrane, the porosity was 39%, 48% and 55% respectively, and the average pore size was 0.198, 0.283 and 0.306(µm) respectively. According to the results MAC(50-35-15) membrane, a promising mechanical strength of 17.9 (MPa) demonstrates a 58% porosity and a permeability of 19980(L/m2.h) of distilled water. Besides, the greywater was further treated with the Fenton process at a pH= 3 and a reaction time of 90 (min) to meet the required standards of reusing wastewaters. The optimal hydrogen peroxide (H2O2) and ferrous ion (Fe2+) values were 500 (mg/L) and 750 (mg/L), respectively. In addition, based on the COD results, the mullite membrane with 78.9% and the MAC(50-35-15) with 63.2% showed the highest and lowest rejection values, respectively. Similarly, the best COD removal efficiency of greywater was obtained at a value of 40 (mg/L) after treatment via the Fenton process.