Study On Integrated Purification Device Of Rural Drinking Water

In our country, the economic development model of rough type is causing the safe drinking water in the rural area threatened, and the trend of this situation is accelerating in the central west region and some poor areas. This is mainly related to these factors such as the living habits of rural areas, scattered residence, enterprises transferred to the peri-urban areas, etc. These factors bring big troubles to the life of peasants and the health of peasants is suffered from hazards too.The rural population is674.145million, accounting for50%of the total population in China. The rural people who enjoys the centralized water supply is accounting for only38%of the total rural population. According to the survey from Ministry of Health, in February2013, the environmental protection administration firstly acknowledged that there were "Cancer Villages" in China which were more than500and are mainly distributed in the Southeast region of China, and that in these regions, the industrial emissions were large and the water was seriously polluted. Now the trend that the water source in large areas is polluted is difficult to be reversed. To ensure the drinking water safety for farmers, the water purification equipments of small size should be developed so as to separately supply the water.In this paper, based on the now available theory and practice in water purification and specific to the purification of rural surface water, the solutions were raised. It was designed as the skid-mounted equipments with integrated type for water purification. Aiming at the hydro-cyclone of enhanced coagulation in process, the research of flow field characteristics was made and the functions of equipments were improved. Ozone pre-oxidation and coagulating sedimentation were chosen as the pretreatment. The reliable quartz sand was chosen to filter during the section of normal processing. Ultraviolet sterilization and membrane separation were chosen in the section of advanced treatment. According to the theory of coagulating sedimentation, the hydro-cyclone with enhanced coagulation in this paper was integrated to one set for mixing, flocculation and sedimentation, and mainly included zones of coagulation, flocculation and sedimentation. The dimension of the hydro-cyclone with enhanced coagulation was designed based on the structural scale of conventional hydro-cyclone. The processing capacity of the hydro-cyclone was940L/H (preliminary design). The fluid calculation software CFX was applied to verify the function of this hydro-cyclone while the standard κ-ε turbulence model was selected. It was found that when the length-diameter ratio was bigger, the micro-vortex proportion of mixing zone would be larger. The velocity gradient G in the mixing zone was obviously bigger than that of flocculation and sedimentation zones. In order to provide better hybrid hydraulic conditions and reduce the short-circuit flow nearby the upper outlet of water; the intersection surface of this equipment was changed into circular arc transition.