The Development And Experimental Study Of The Integrated Water Purifying Equipment With Spiral Lamella

With the rapid development of urbanization and building new socialist countryside, the small town in the southwestern and rural area face that water resources are being polluted and high tuibidity in rainy season. And in the aera, water resources are always in shortage. And the effluent qualities of the existing equipments fail to meet the "Standards for drinking water quality" GB5749-2006. In order to ensure social stability and people's health, research and development of new Integrated Equipment for Drinking-water purifying that are application to the small town in the southwestern and rural area is very importment.New technique of the Spiral slant lamella is applied to sedimentation process of the Cylindrical Integrated water purifying equipment. The spiral lamella design Shape to make full use of space to reach 100% space utilization, thereby increasing precipitate efficiency reducing the occupied area and saving investment. In this thesis, the design parameters and fabrication of the Spiral slant lamella sedimentation process are expatiated. And the process parameters of the enhanced grid flocculation and rapid filter are also analyzed in this thesis. The treatment of Hei-Shuitan river raw water using the Integrated water purifying equipment is studied through experiment. The main contents of the experiments include: the experiment of the optimal coagulant (PAC) dosage in design inflow, treatment effect of raw water under continuous work condition in optimal coagulant (PAC) dosage, especially analyzed the treatment effect in high turbidity water and overload inflow.It was showed by the experiment of the optimal coagulant (PAC) dosage under design inflow 240 m3/d that optimal dosages 10~15 mg/L in common raw water average turbidity at 99 NTU and 35~45 mg/L in high turbidity water. During the experiment, in common raw water the average turbidity of sedimentation tank, filter effluent are 0.38~2.14 NTU, 0.09~0.52 NTU respectively. The removal ratios of UV254, CODMn and NH4+-N are 31.03~42.19%, 26.5~46.6%and 11.1~28.6% respectively. During the high turbidity water experiment, the turbidity of Spiral slant lamella sedimentation tank, filter effluent are below 5 NTU and 1 NTU respectively.After Integrated water puriying equipment works normally running under design inflow 240 m3/d, when the turbidity of the water is about 99 NTU, sludge discharge three times a day for the second flocculation and sedimentation tank, and the turbidity of sedimentation tank effluent is about 1 NTU, and the water quality is stable. The sludge discharge times should accord to the actual situation, when the raw water turbidity and water inflow change suddenly. The time is about 30 seconds for every sludge discharge. The filter runs 24 hours of the rapid filter, when the wash rate 12~15 L/(s·m2), it takes about 10 minutes to backwash the effective quartz sand layer.During different inflow 192 m3/d,240 m3/d and 288 m3/d experiment, the average turbidity of the sedimentation tank effluent are 0.63 NTU,0.84 NTU,1.91 NTU, and the average turbidity of the rapid filter are 0.16 NTU,0.16 NTU,0.36 NTU. The results of the different inflow experiment indicate that, the Integrated Drinking-water Treatment Equipment with Spiral Lamella has a greater ability to resis hydraulicshock loading and it suitable for water need instability small town and rural area.The results of the economic analysis in design inflow 240 m3/d show that the total investment of the equipment is 64 400 RMB, the specific investment is 268.3 RMB/(m3·d), and the unit operation cost of it is 0.119 RMB/m3. The economic analysis indicated that the equipment has certain economic advantages and it suitable for backward economic forms of western small towns and rural area, and has good application prospect.