Feasibility Evaluation of Cloth-made Disc Filter over Rapid Sand Gravity Filter in Drinking Water Filtration
摘要
The main aim of this study is to compare the efficiency of Rapid Sand Filter (RSF) and Disc Filter (DF) in drinking water treatment based on filtration rate, pollutants removal, and footprint. For this, lab-scale RSF and DF were designed and fabricated with the flow rate of 500 L/h at the filtration rate of 6 m3/m2/h. The DF incorporated rotating stainless-steel discs that acts as a support framework, each was completely covered with polymeric filter cloth such as polypropylene or polyester with a pore size of 5 µm and 10 µm. Kaolin simulated water was used as feed water with the turbidity adjusted from 5, 7.5, 10, 15, and 20 NTU. The study revealed that the turbidity removal of the DF was 47% higher than that of the RSF, and the TSS removal efficiency was 25% higher than RSF. However, filtration rate is comparable in both RSF (≈5 m3/m2/h) and DF (> 5 m3/m2/h). A comparative evaluation of water filtration efficiency in cloth made disc filter (CMDF) revealed that the polypropylene-based CMDF outperformed the polyester-based CMDF, and for both materials, the 5 µm pore size filter cloth exhibited higher pollutants removal efficiency than the cloth filter with 10 µm pore size. Moreover, during the filtration in DF, the rotating disc module showed a higher filtration rate than without rotating. The filtration efficiency comparison found that DF was more efficient than RSF. Moreover, the techno economic analysis revealed that the DF is more cost-effective technology than the RSF and can be retrofitted into the existing water filtration system.