硅酸钙改性及其处理焦化废水的实验研究-环境工程专业论文.docxVIP

内蒙 内蒙古科技大学硕士学位论文 III III was increased, at the same time the surface area had been improved. Above these changes the modified calcium slilcate had a better adsorption performance than un-modified. (4) The treatment of biologically treated coking wastewater with Calcium Slilcate modified by ultrasonic wave was experimentally investigated. At room temperature the optimal operating conditions for adsorption were: the modified calcium slilcate dosage was 2.0g/100mL, the time of adsorption was 45 min, the value of pH was 6, at that time the optimum rates of COD and NH3-N respectively were 41.16% and 66.16%. Under the same experiment conditions, the modified calcium silicate was obviously had higher adsorbability than calcium silicate, fly ash, specially the removal rate of NH3-N higher than activated carbon by about 15%, the removal rate of COD lower than activated carbon by about 15%. The adsorption kinetics experiment indicated that: the adsorption process of NH3-N with modified calcium silicate was correlated well with the Langmuir adsorption isotherm models. The single molecular layer adsorption played the mainly role in the whole adsorption process. The maximum adsorption capacity of modified calcium silicate was 6.77mg/g, increased about 89.6% after been modified. The adsorption process of NH3-N with modified calcium silicate followed second-order kinetics model and the adsorption rate of NH3-N was governed by liquid film diffusion and internal diffusion. In conclusion, the energy effect and mechanical effect played an HYPERLINK /w/effective/ effective role on the modification process of calcium silicate which caused by the ultrasonic cavitation action. These actions changed the structure and surface chemical properties of calcium silicate which improved its capability of adsorption for pollutants. Key words: Calcium slilcate；Modification；Adsorption；Coking wastewater - - PAGE 1 - 目 录 摘 要 I AbstactII HYPERLINK \l _bookmark0 引 言 - 1 - HYPERLINK \l _bookmark1 1 文献