Study On The Mechanism Of The Vortex Flocculation Strengthening Sugar Juice's Settlement And Manufacture Of Flocculation Reactor

Sulfitation and flocculation are a major operation in sugar production. However, the sulfitation is not insufficient in most of sugar industries. Which will cause high calcium salt and SO₂ contents in the purified juice, forming the poorer density of CaSO₃, adsorbing less colloid content, colorants and other impurities, reducing subsidence velocity. The bad flocculating operation cause the retention time of juice longer then longer in the flocculation which is unfavorable to the sugar production.Based on the situation of sulfitation and flocculation of the cane sugar industry, the vortex flocculator uses the mechanism of the dynamic swirl flocculation. using the fluid shear force of inertia and centrifugal force, strengthening sulfitation sufficiently, generating sufficient calcium salt precipitation. At the same time, colloid content can be adsorbed by the flocculant. generating more higher density and bigger particles, accelerating subsidence velocity, reducing the retention time of juice, reducing the loss of sugar.The novel micro-vortex flocculator for cane juice was developed in this research, in order to enhance sulfitation and flocculation the mechanism of enhancing flocculation were studied. The vortex flocculating experiment was preliminarily applied in sugar processing, obtaining satisfactory results. Main research contents and results of this thesis covered:1. Investigation on the vortex flocculation mechanism. Based on the deduced model for micro-vortex flow within the corrugation, the model for the corrugation was developed according to the flocculation kinemics. It can beexpressed as:(?)2. Investigation on the influencing factors of the vortex flocculator. Established of experiment model to studied the effecting factor of the vortex flocculator. Then design the single factor experiment and get the optimized flocculation condition as follow as: the sample's concentration is 4g/L, the sample's flow is 0.75m³/h. the quantity of flocculant adding is 3mg/L^-1, and the whisking speed is 400r·min^-1.3. Establishment of the model of dimensionless numbers for the flocculating efficiency. Experiments were performed to investigate the influences of operational parameters on the flocculating efficiency. A model of dimensionless numbers for prediction of flocculating efficiency was established base on the method of dimensionless number analysis. The relation of the flocculating efficiency with the other dimensionless numbers could be expressedasη=10^0.5639(U_t/U)^0.0234(GT)^0.0134(H/D)^0.53Re^-0.2827.4. Investigation on the Influencing Factors of flocculation. Experiments were performed to investigate influencing factors of flocculation the flocculating efficiency, which are including type and amount of flocculant, temperature, pH value, hydraulic factors. Then design the single factor experiment and get the conclusion as follow as: flocculant P3000 is best for flocculating. When using the amount of flocculant from 1mgL^-1 to 5mgL^-1, the temperature from 60℃to 95℃, the more using amount the better flocculating effect. Effect is smaller when the pH value is from 6.6 to 7.4. The effect of flocculant is better using Calcium carbonate as the flocculation's core.the flocculation is best when GT is 44496.5. Research on the application of the vortex Flocculation in sugar industry. The application of vortex flocculator in flocculation process, subsidence velocity, filtration velocity, apparent purity of purified juice, colour, turbidity, reducing sugar and calcium salt content were determined and then to compare and analyze the effect between vortex flocculating and static flocculating. subsidence velocity increased by 47.96% filtration velocity increased by 30.18%, purified juice apparent purity increased by 0.77AP, colour decreased by 16.46%, turbidity decreased by 24.63%, and calcium salt content decreased by 11.01%, reducing sugar decreased by 6.39%,...