| 高藻原水预臭氧强化混凝除藻特性研究 |
| 摘要点击 2954 全文点击 1683 投稿时间：2008-08-18 修订日期：2008-11-16 |
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| 中文关键词 藻类 臭氧 强化混凝 消毒副产物 饮用水 |
| 英文关键词 algae ozonation enhanced coagulation disinfection by-products drinking water |
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| 中文摘要 |
| 采用有机物表观分子量分级、树脂分级等手段表征了原水有机物特征，通过实验室试验和中试运行对预臭氧强化混凝藻类去除效果、溶解性有机物（dissolved organic carbon，DOC）的变化和去除、消毒副产物的控制等进行了研究，并利用藻类活性测试研究了预臭氧强化混凝除藻机制.结果表明，采用适当浓度的臭氧（如1.0 mg·L-1）进行预氧化，可有效提高藻类去除率，从常规混凝沉后水的55%～85%上升到95%左右，最高去除率达到99.3%（预臭氧1.0 mg·L-1，PACl 3.0 mg·L-1）；THMFP(trihalomethanes formation potential)总体去除效果从常规处理的117 μg·L-1降至46 μg·L-1；高投量（≥2.0 mg·L-1）预臭氧，促进了藻类灭活，但影响了有机物的去除.藻类活性评价臭氧氧化和常规水处理过程对藻类作用存在显著差别.常规混凝对藻类活性影响不明显，不同剂量混凝剂对藻类活性影响差异不大；而臭氧对水体中的藻类有灭活作用，在0.5～2.0 mg·L-1臭氧条件下，藻类活性降低至12以下，且该指标随着臭氧剂量的加大显著降低.紧随其后的混凝过程中，混凝剂或者其水解过程的某些成分对臭氧灭活藻类有增效/催化作用.与传统的显微计数法相比，藻类活性试验更明确地表征水处理过程对藻类生存状态的影响，为水处理除藻机制研究和工艺设计提供更清晰的信息. |
| 英文摘要 |
| Apparent molecular weight distribution (AMWD) and resin fractionation were used to characterize organic matters of the raw water. Removal of algae, change and removal of dissolved organic carbon （DOC）, disinfection by products (DBPs) control during the preozonation enhanced coagulation treatments in the jar-scale and pilot-scale experiment were studied. Algae activity (AA) was measured and used to elucidate the mechanisms of algae removal by above treatments. Results show that algae removal can be improved distinctively by proper preozonation, as the ozone dose 1.0 mg·L-1, for instance. Algae removal could be increased from 55%-85% by traditional coagulation to 95% by enhanced coagulation after preozonation; and the best removal achieved 99.3% with ozone 1.0 mg·L-1 and PACl 3.0 mg·L-1; the residual THMFP (Trihalomethanes formation potential) was lowered from 117 μg·L-1 by traditional coagulation to 46 μg·L-1. But higher dose of ozone (as ≥2.0 mg·L-1）impairs organic matter removal, although it decreases algae activity further. Significant differences were found in algae removal by AA detection between ozonation and traditional coagulation. Traditional coagulation had little effect on AA no matter the different PACl doses; while AA decreased clearly after ozonation. AA was lowered below 12 under 0.5-2.0 mg·L-1 ozonation; and it kept decreasing with increase of ozone dosage. During the following coagulation, coagulant or some of its hydrolysised components enhanced the AA decrease by ozonation. Compared to the method of normal microscopy counting, AA test expresses the influence of algae living state by water treatment processes more clearly; which would provide treatment process designer with more distinct information about algae removal mechanisms and how to arrange the treatment processes to improve algae removal. |
