Experimental Study On The New Processes Of Tube Microvortex Coagulation-Microporous Atomized Air Flotation

As an important index for drinking water quality, turbidity reflects the degree of removing suspensions, microorganism and organic matters from water. The Sanitary Standard for Drinking Water Quality was promulgated in China in 2001 and the turbidity was restricted below 1NTU.Conventional water treatment processes can't reach standard for the serious water pollution. Also the influencing factors of biological pretreatment are great, and the investment of advanced treatment and the fee of running are all expensive. So, enhancing and reconstructing conventional water treatment processes is an economical and feasible method to achieving 1NTU water quality standard.The turbidity of the inflow of filtration is an essential controlling parameter of the operating status and expense of conventional water treatment processes. In order to meet 1NTU water quality standard and be most economical, it should be controlled about 3~5NTU. There for, the processes before filtration should be enhanced and reconstructed to satisfy the request of the turbidity of the inflow of filtration. At present, a vortex reactor is invented according to microvortex coagulation theory. The effect of the flocculation is good by using it, but its manufacture is complex. While the dissolved air flotation is mostly used in the reconstruction of the air-floating filter, this process has many assistant equipment and its investments is big.According to these conditions, this research attempt to use a new tube padding which is easily produced as the flow-disturbing installation of the flocculation reactor, and take a new atomize-aerated tube as the micro-air-bubble producing equipment of the air floatation process, thus the project of enhancing and reconstructing conventional water treatment processes can be simpler and economy. The concrete content of the research included two aspects: the hydraulic characteristic and coagulation effect of the new tube flow-disturbing padding and the best energy consumption allocative decision under this flocculation mode, as well as the water cleaning effect and influence factors of the air flotation process by using atomize-aerated tube. The results of the research can be used in the technique reconstruction of the small and medium water works for achieving 1NTU water quality index.The experimental study indicated that there is a power function relation between the energy consumption of the padding and the water-flow, and it has a good correlation. The best energy consumption allocative decision under this flocculation mode has also been found by the orthogonal experiment. In the air flotation experiment, the atomize-aerated tube can produce smaller diameter micro-air-bubble. The main influence factors of the flotation effect are the air-water ratio and the air load per meter. Through the experiment, it is found that the best air-water ratio is 8‰, and the best air load per meter is 25.6L/h·m.