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From anaerobic swine wastewater removal and recovery of phosphorus (P), important elements, pollution control and resource utilization of the waste water, the crystallization of calcium phosphate (Calcium Phosphate, CP) is a major process. The paper systematically studied the simulation and the actual swine wastewater system solution conditions CP crystallization reaction efficiency and phosphorus removal rate, to obtain the optimal process parameters, the use of modern means of instrumental analysis carried out to characterize the product CP and CP formation mechanism was discussed. First simulated wastewater treatment object, CP crystalline small test beaker experiments, effects of pH, calcium (Ca) salt, ammonia (NH3) salts, magnesium (Mg) salts and carbonate (the CO 3 observed 2 - ) concentration as well as a variety of different conditions on organics, seed crystallization reaction efficiency of CP, phosphorus removal rate, and by means of scanning electron microscopy - energy spectrum analyzer (SEM-EDX) the product form, the use of X-ray diffraction (XRD) to determine the product composition. Studies show that CP crystallization reaction optimum pH value 5.0; With the increase of the Ca / P molar ratio, P, removal increases; optimum Ca / P molar ratio of 2.0 the excessive Ca salt dosing amount to improve the efficiency of the reaction is not obvious; similar nature in phosphorus removal, magnesium and calcium, can promote phosphorus removal. Ammonium salts exist conditions when Mg 2 concentration is increased to a certain analog solution will magnesium ammonium phosphate (MAP) crystals to produce; CO 3 2 - reduce CP crystal generation amount through a combination of calcium ions, so that removal of the P greatly reduces, but does not affect the crystalline form and purity of the CP. Anaerobic swine wastewater treatment, the CP crystal small test experiment, the effects of pH, Ca, Mg salt dosage and concentration of organic matter CP crystallization reaction efficiency of phosphorus removal rate. The studies show that in addition to increase the reactant in the dose increased, but other cases with simulated wastewater roughly the. And under high pH conditions, larger increase, but does not change the reaction of the Ca salt concentration optimal pH; CP crystallization reaction on the chromaticity of the waste water and of of COD Cr , and to have certain addition to the role; the decrease of the concentration of organic matter, there is conducive to the crystallization of CP of the reaction; XRD, SEM-EDX analysis revealed, the reaction under the conditions obtained from swine wastewater in the best crystals of high purity of the CP. The application of air aeration to improve pig waste water pH, CP crystallization is entirely feasible; pH value as the aeration time is increased linearly up to a maximum of 9.21; after starting the reaction, i.e., a white flocculent precipitate appears, followed by a gradual increase. Expand the test still aeration based on the results in line with mainly Removal of phosphorus to calcium salts, by means of scanning electron microscopy - energy spectrum analyzer (SEM - EDX) and X-ray diffraction (XRD) to verify phosphate crystals Phosphorus Removal The effect is very good.
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