The Study On Denitrification Releasing Carbon Filler Based On The Wastewater Of Low C/N Ratio

At present, the water of many countries and regions are different levels polluted by nitrate. Biological nitrogen removal process has the advantages of high efficiency, low energy, so it is widely used to govern the water polluted by nitrate, but the problem of lack of carbon source in the water has greatly restricted the efficiency of biological nitrogen removal. In this study, a new releasing carbon material was prepared, and had studied the process of preparation, the physical and chemical nature, the releasing carbon properties, the biological nitrogen removal performance of the new releasing carbon material.With corn starch and wheat starch as the releasing carbon fractions, PVA as skeleton materials, using the gel molding process, had prepared of the two categories (the Y type and the X type), eight kinds releasing carbon materials. The compression performance of the materials reach to1066.67～1502.22KN/m2. Starch and PVA has good compatibility. Starch forms a membrane structure wrapping in the surface of PVA skeleton. And with the two-phase content changing, the surface morphology of the materials show a gradual changing trend. After static releasing carbon of materials, the fusion of starch and PVA is more obvious, there has been dissolved and broken phenomenon in the surface of material.Because static releasing carbon capacity of X type materials are excessive, X type materials do not have the sustained releasing characteristic of polymer material, their price are higher and other shortcomings. Therefore, select Y type material as the main object of study. The static releasing process of materials at room temperature is similar to the Fick diffusion mechanism, the static releasing rate coefficient k are able to evaluate the releasing properties of materials. The ratio of material and the addition of a-amylase can significant change static releasing rate coefficient k, their range are22.547～3.888mg/(g·d0.5) and10.218～24.770mg/(g·d0.5).Through the static biological nitrogen removal experiment, achieved good biological nitrogen removal using the material. The biological nitrogen removal rate of material is2.75gN/(m3·d), it greater than or equal and the biological nitrogen removal rate of the natural polymer. However, the releasing carbon material prepared in this study has advantages of good mechanical properties, release carbon controllable and easy to use. Therefore, the releasing carbon material prepared in this study will have broad application prospects.