Study Of Micro-polluted Water Treatment By Contact Filtration-Granular Activated Carbon Adsorption-UF Technology

With the micro-polluted problem of the drinking water resource intensifying, the improvement of drinking water standards and people's requirements for the drinking water, the conventional water treatment process, which aims mainly at controlling turbidity, chroma and total bacteria, is increasingly difficult to ensure the safety of drinking water. Furthermore, the factors such as economic conditions, the safe drinking water technology of city does not apply to small towns and so on, are hampering seriously the economy of small towns and social comprehensive development. The problem of drinking water treatment in Chinese small cities and towns is particularly prominent. Therefore, it is necessary to study and develop the drinking water treatment process which is suitable to small towns.According to the characteristics of small towns, the thesis design and develop the contact filtration-granular activated carbon adsorption-ultrafiltration water treatment apparatus to treat micro-polluted raw water. The thesis describes in detailed and analyses the apparatus characteristics, the design parameters, the use of this apparatus in the Yangtze River micro-polluted water treatment and the effluent water quality of the apparatus parts, the situation of ceramic filter, granular activated carbon and ultrafiltration membranes'cleansing, then makes economic and application analysis of the apparatus.By the comparison and argues on different coagulants, and changing coagulant dosage and the filtration velocity rate, the handling capacity of the device was identified as 1000 L/h, the coagulant dosage was 6mg/L appropriately and the coagulant PAC under test conditions. In this operating and test conditions, the average turbidity of effluent was 0.08 NTU, the proportion of removal was 99.9%; the average ammoniate nitrogen was 0.10mg/L, the proportion of removal was 50.5%; the average nitrate nitrogen was 0.95 mg/L, the proportion of removal was 2.93%; the average color was 5 degrees, the proportion of removal was 73.9%; the average TOC was 0.26mg/L, the proportion of removal was 89.2%; the average CODMn was 0.77 mg, the proportion of removal was 64.9%; the bacteria was 0 cuf/ml, the proportion of removal was 100%; the E. coli removal was 0/L, the proportion of removal was 100%. The effluent water examined by the apparatus reached the national drinking water standards. It has practical significance to protect the safety of small towns'drinking water. Ceramic filter's anti-cleansing cycle was 10~12h and used gas-water anti-cleansing. Granular activated carbon's anti-cleansing cycle was 7~10 days and used hydraulic anti-cleansing. Ultrafiltration membranes used dead-end filtration, physical cleaning method used water anti-cleansing. In test, ultrafiltration membranes'physical cleaning cycle was 2 hours in first month, then once every hour. At first month and third month, ultrafiltration membranes were cleaned with chemical, and used two different chemical reagents, but the effects very significant.The investment cost of apparatus was 429.57 yuan / (m3/d), and the operating cost was 1.23 yuan/m3. The experimental apparatus occupied 1.2m2, was easily facilitate disassembled, had strong applicability in our small towns.