Ncaf Vortex Concave Flotation Device Development And Applied Research

As a high-efficient separation technology, flotation has quickly developed in water and waste-water treatment since 1970s. At present, the common technology of flotation are dissolved air flotation(DAF) and cavitation air flotation(CAF). Compared with DAF, CAP has the advantages of lower operation expenditure, higher efficiency and simpler structure.In this paper, the current research situation of flotation technology and its application in water and waste-water treatment is reviewed. The mechanism of cavitation air flotation and the design mechanism of CAP cell are studied systematically and the design theory of CAF cell is proposed.A miniature water-jeting CAF cell, which can treat O.lt water per hour, is designed and made. The alga water of Dian Chi, coking waste-water and paper industry waste-water are treated by the water-jeting CAF cell respectively.The experimental results show that the reagent consumption is low, the flotation time is short and the purification efficiency is high. If alga water is treated by this cell, the removal pergentage of alga content and that of turbidity are both 99%. If coking waste-water is treated by this cell, the purification efficiency of COD and that of oil are 56.5% and 99.8%, respectively. If paper industry waste-water is purified by this cell, the purifying efficiency of SS and turibidity are99.9% and 96.3%, respectively.The three kinds of waster-water mentioned above are treated by this cell efficiently. If single flocculant is adopted in the experiment, the purification efficiency of organic flocculant is higher than that of inorganic flocculant. The consumption of the former is lower than that of the latter. If complex reagent is adopted, its purification efficiency is higher and its consumption is lower than the corresponding index of the single reagent.