【作者】 娄敏；

【导师】 廖柏寒； 王毅力；

【作者基本信息】 湖南农业大学 ， 环境工程， 2005， 硕士

【摘要】 水体中腐殖酸作为影响水质安全稳定性的重要的有机物,目前已成为国内外关注的焦点。本论文研究了分别以聚合氯化铝（PAC）和聚合氯化铁（PFC）为絮凝剂时微涡旋絮凝-逆流气浮-纳滤集成工艺去除水中腐殖酸的工艺特征和效果,研究了微涡旋絮凝-逆流气浮-纳滤集成工艺去除水中腐殖酸的工艺动态运行特征。主要试验结果如下: 1.以聚合氯化铝（PAC）和聚合氯化铁（PFC）为絮凝剂微涡旋絮凝-逆流气浮工艺去除水中腐殖酸时,在最佳投药量下,出水水质都符合纳滤系统预处理单元的要求,而且该工艺需要絮凝剂的量较低。该预处理系统与纳滤系统组合的集成工艺可以使水中的腐殖酸有机物浓度大大降低,含Q5633型纳滤膜的流程比含M-N1812A型纳滤膜的流程效果好。以聚合氯化铝（PAC）为絮凝剂时前者出水的TOC值由1.213～1.780mgL^-1下降到0.243～0.473mg L^-1,COD_Mn值由1.13～1.20mg L^-1下降到0.57～0.77mg L^-1,UV_254nm值由0.017～0.013下降到0～0.0033;后者出水的TOC值却只下降到1.0mg L^-1左右,COD_Mn值下降到0.82-0.92mg L^-1,UV_254nm值下降到0.008～0.012。以聚合氯化铁（PFC）为絮凝剂时前者出水的UV_254nm值由0.003～0.033降到0,TOC值由1.190-1.411 mg L_-1降到0.418～0.554mg L^-1,COD_Mn值由1.14～1.49 mg L_-1降到0.60～0.69mg L^-1;而后者出水的UV_254nm值却只降到0～0.011,TOC值降到0.932～1.0mg L^-1,COD_Mn值降到0.95～1.2mg L^-1。含Q5633型纳滤膜的流程有95%以上的脱盐率,而含M-N1812A型纳滤膜的流程脱盐率则很低。因此从制取饮用水的目的来看,流程4是最优的选择;而以从最大量的去除有机物为目的来看,流程3则是最优选择。另外,尽管保安过滤/活性炭预处理有利于纳滤膜出水水质的提高,但活性炭柱与纳滤膜能去除的有机物种类是有些重合。水中颗粒物粒度分布表明,以聚合氯化铝（PAC）为絮凝剂时絮凝后和气浮出水中颗粒物粒度分布的中位直径(d₅₀)分别为10～14μm和8～13μm;以聚合氯化铁（PFC）为絮凝剂时絮凝后和气浮出水中颗粒物粒度分布的中位直径(d₅₀)分别为21μm和16μm。经过保安过滤器或保安过滤器/活性炭柱,水样中的颗粒物的d₅₀为0到几个μm。经过纳滤膜后,出水无颗粒物。 2.确定其运行周期为72小时,通过微涡旋絮凝-逆流气浮-纳滤集成工艺的更多还原

【Abstract】 Humic acids in the water are one kind of the most important natural organic matter NOM which affect the water quality stability and nowadays that have become the focus of notice in worldwide research. This paper mainly studied the characteristics and the removaling of humic acid in water by the integrated processes of micro-eddy flocculation （MEF） - counter current dissolved air flotation （CCDAF） -nanofiltration （NF） when using PAC and PFC as flocculant, and the dynamic running characteristics of MEF - CCDAF - NF integrated process were studied, combined with micro-eddy flocculation （MEF）, counter current dissolved air flotation （CCDAF） and nanofiltration （NF）. The main results showed as follows:1. The results showed that water quality of MEF - DAF process matched the requirement of pre-unit for membrane system at optimum dosages of PAC and PFC flocculant. These dosages were less than these in flocculation-sediments processes. The MEF - CCDAF - NF integrated processes could remove most of humic acids in water, and Flowage one with Q5633 NF unit had better performance than Flowage two with M-N1812A. It could be demonstrated by the better quality of effluent water after Flowage one (0.243-0.473 mg L^-1 of TOC, 0.77-0.77 mg L^-1 of COD_Mn, 0-0.0033 of UV₂₅₄nm) than after Flowage two (about 1.0 mg L^-1 of TOC, 0.82 -0.92 mg L^-1 of COD_Mn , 0.008-0.012 of UV₂₅₄nm) when using PAC as flocculant. When using PFC as flocculant also demonstrated the better quality of effluent water after Flowage one (0.418⁰.554mg L^-1 of TOC, 0.60⁰.69mg L^-1 of COD_Mn, no UV₂₅₄nm absorbance) than after Flowage two (0.932-1.0 mg L^-1 of TOC, 0.95-1.2 mg L^-1 of COD_Mn, 0-0.011 of UV₂₅₄nm) there was only 5% residual TDS after with Q5633 NF unit ,but high TDS content after with M-N1812A NF unit. So, Flowage four is the best Flowage when producing drinking water, but Flowage three is the best when removing the most of natural organic matter . Moreover, the NF permeat quality could be improved when activated carbon （AC） unit following MF, but some kinds oforganics in water could be absorbed by both AC and NF units. These led leading to decreasing the stepwise removal rate for organics in water by NF unit. When using PAC as flocculant. the dso of particle size distribution （PSD） in flocculated water and floated one are 10¹4u.m and 8¹3|im for Flowage one, and the dso of particle size distribution （PSD） in flocculated water and floated one were 21u.m and 16u.m when using PFC as flocculant, respectively. Sometimes particles in water with several microns of dso, could still be found after MF or MF-AC units, no particles exist in NF permeat.2. The dynamic running characteristics of MEF - CCDAF - NF integrated process were studied, combined with micro-eddy flocculation （MEF）, counter current dissolved air flotation （CCDAF） and nanofiltration （NF）. Its running period was about 72 hours when used to remove humic acid in three different kinds of raw water. The results showed that the MEF - CCDAF - NF integrated processes could remove most of humic acids in water, but Flowage one with Q5633 NF unit performed better than Flowage two with M-N1812A one. When treating raw Water two with PAC flocculant in the integrated processes, the better quality of effluent water after Flowage one was 0.45mgL’’ of CODMn, fluctuated UV254nm value around 0.0033, and only 5% residual TDS , and the effluent water quality after Flowage two was OJSmgL"1 of CODMn , much less than 0.0075 of UV254nm, and sometimes no detected, and still existed 94%⁹0% TDS. Moreover, when treating raw Water one and Water three, the effluent water quality after Flowage two was 0.0054 of average UV254nm, higher than that for raw Water two with 0.0033 of average UV254nm. A little better effluent water quality was found for the integrated processes with PFC flocclant than with PAC, this could be attributed to better PFC performance in MEF - CCDAF processes for humic acids removal and higher quality pre-treated water. However, the integrated processes could have a stronger ability for buffering the change of raw water quality when PAC as flocculant. The activated carbon unit in the integrated processes improved its NF permeat quality, but didn’t prolong its running period. These demonstrated that membrane pollution mainly accredited to inorganic matters.更多还原