溶解氧对催化氧化滤料制备及除锰性能影响研究

中试条件下,考察进水溶解氧(DO)对催化氧化滤料制备及其除Mn2+性能的影响。结果表明,进水DO的质量浓度由1.5 mg/L提高至6.5 mg/L可将滤柱启动时间由36 d缩短至14 d;新制备滤料在不同DO含量条件下性能有所差异,但均至少可去除约3 mg/L以上的Mn2+,满足GB 5749-2006要求;较高的进水DO含量有利于水中Mn2+的进一步去除。2种滤料除Mn2+过程均符合准1级动力学关系。滤柱长期运行时,若反冲洗过程中气量超过12 L/(s·m2)会对滤柱正常运行产生不利影响。扫描电镜观察2种DO含量条件下所形成的活性氧化物膜形貌差异不大,其性能差异可能与滤料表面氧化物含量及其化学结构有关。

Study on the Influence of Dissolved Oxygen on the Preparation of Catalytic Oxidation Filter Media and Manganese Removal Performance

The influence of dissolved oxygen(DO) on the preparation of catalytic oxidation filter and the performance of manganese removal were investigated under pilot test. The results showed that the start-up time of filter column could be shortened from 36 d to 14 d by increasing DO mass concentration from 1.5 mg/L to 6.5 mg/L. The performance of the new filter media was quite different under different DO conditions, but it could remove manganese at least 3 mg/L, which met the removal requirements of GB 5749-2006. The higher DO content was beneficial to the further removal of manganese in water, and the two filters were in accordance with the pseudo first-order kinetics. If the air volume exceeded 12 L/(s·m2) during backwashing, the normal operation of the filter column would be adversely affected. The results of SEM analysis showed that the morphology of the active oxide films formed under the two DO content conditions was not very different, and the performance difference might be related to the oxide content and chemical structure of the filter media surface.