| China's water pollution situation will not fundamentally change in the coming long futur- e, and urban water demand on the water quality is getting higher and higher. Most of the small and medium-sized water plant are very difficult to be up to standards, and carrying out techn- ological transformation are facing great pressure due to economic, technical constraints.Practice showed that when the turbidity was low,the organic matter content can be subst- antially reduced and the water quality greatly improved. Organic matter and ammonia can be multily-removed by coagulation and precipitation, suspended sludge flocculation and bioche- mical reactions. One of the current water treatment study is to develope an eqipment with lo- wer turbidity, higher removal rate of organic matters, low-power, low-cost. For this reason, e- xplorations from theory to experimention were conducted in this paper.Theoretical analysis found that coagulation process was difficult to complete by Brown motion alone;there was a most-disadvantaged size which was 2~3μm in the cagulation pro- cess; mixed equipment demand rapid spread within the entire water body in very short time; Large-scale vortex can form large-scale proliferation throughout the section.however, it is ve- ry small-scale vortex which impact focculation's form-ation and growth; reasonable and eff- ective butt over particles should be controlled; floc's size and density depend on the ability of pharmaceutical association and turbulent shear force; the selection of micro-scale vortex have two types: dissociation of boundary layer and resistance-flow perforation plate; to get high de- nsity floc, ways should be find to increase the strength of floc;if the proportion of micro-scale vortex can be greatly increased,the risk of particle collisions can significantly be increased。Based on the above, the entire-process-micro-vortex (EPMV) view was brought out.The entire-process-micro-vortex hydro-clarifier (EPMVHC) was designed in this paper based on the theoretical analysis. The experimental results showed that the turbidity of water treated by device was about 1 NTU; organic matter and ammonia, and other indicators can be up to standards;when coagulant alone conditions can be controlled as follows: G 102,HRT 1.6 min,head loss 0.10 m;when joint: G 127-108-102,HRT 6.1 min,head loss 0.58 m; when the quality of the water was well, sludge concentration is about 20~25 g/l both alone and joint; settlement rate in 5 min was about 9~16%;the formation of high -density need the meet of coagulant and shear force;Floc on the adsorption of organic matter accounts for about 26% to 11% when the turbidity was 1~7 NTU;small plate spacing ramp handling capacity superior to the traditional inclined board because of the unique structure,its turbidity-deduce mechanism is contact flocculation.
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