“加压上浮法”应急除藻技术在水源地的应用示范

近年来,太湖蓝藻水华问题日趋严峻,除藻技术是解决该问题最直接而有效的手段,对现有各类除藻技术进行了比较,并以"加压上浮法"应急除藻技术在苏州阳澄湖局部地区的示范工程为例,介绍了该方法的技术原理、技术实现以及在工程应用中的实际意义,为同行在水源地或特殊功能区除藻技术的应用提供参考。     

A-O工艺污泥疏水比率与污泥活性的关系

通过A-O工艺对印染废水的降解处理,研究了不同污泥活性下微生物疏水比率和COD去除率的变化规律.结果表明,污泥活性指标ATP浓度与微生物疏水性之间存在一定关系,并对COD去除率产生一定的影响.缺氧污泥的活性指标ATP浓度在0.38～0.77 mg/L范围时,污泥微生物的疏水性最好且疏水比率最高值为84％,COD的去除率最高,为70.01％;好氧污泥的活性指标ATP浓度在0.86～2.17 mg/L范围时,污泥微生物的疏水性最好,疏水比率最高值为75％,COD的去除率最高为96.2％.     

牛粪堆肥升温菌剂的筛选及其作用机制

以糖、淀粉、蛋白质、纤维素培养基及菌株增殖倍数、菌株性能等为筛选方法,从牛粪低温堆肥中筛选不同原料重要功能菌并组成功能菌剂;以不同类别原料菌及单菌株发酵实验对升温机制进行研究。结果表明,芽孢杆菌、假单胞菌、纤维单胞菌及小孢霉菌等为重要功能菌;菌剂起温快,升温效果好,48 h堆体即由低温进入中温,5 d达到高温,腐熟时间可缩短至约17~18 d;糖功能菌升温效果最为显著,淀粉及蛋白质功能菌次之,纤维素功能菌升温能力较弱;菌株利用各种原料能力越强,增殖速度越快,对升温作用越大。各菌株充分利用基质各成分,紧密协同和促进,是低温堆体发酵升温的主要作用机制。     

热水解超声组合预处理对污泥厌氧消化产气潜力的影响研究

针对城市污泥厌氧消化由于融胞困难所导致的消解速率低、产气量低等问题,采用热水解与超声组合的方法对污泥进行预处理,考察经预处理后污泥融胞效率的变化及对厌氧消化产气潜力的影响.结果显示,热水解与超声波组合工艺对污泥的破胞作用明显,在30 min热水解与0.53 W/mL超声声能密度组合工艺反应60 min条件下,相对于处理前污泥,预处理后污泥溶解性COD(SCOD)溶出率可提高41.6％,蛋白质增加值达282.7 mg/L,污泥厌氧消化的产气潜力显著增加;30 min热水解分别与0.53、0.33 W/mL超声声能密度组合工艺对污泥破胞效率的差异不大;随着超声时间的延长,在组合预处理工艺前20 min内SCOD的溶出速率较慢,20260 min时溶出速率逐渐提高.试验结果可为城市污泥厌氧消化预处理工艺的选择提供一定的理论依据.     

两种AHLs信号分子对生物膜法养殖污水处理条件下水体内环境的影响

为提高生物膜法处理养殖污水的效果,对不同信号分子条件下的生物膜处理情况进行研究。在室内循环水养殖系统中,设定3个实验组和1个对照组,分别添加乙醇、C6-HSL、N-3-oxo-C8-HSL和蒸馏水,并在模拟过程中取样分析。实验结果表明,3个实验组附着基上的生物量明显多于对照组,尤其是添加N-3-oxo-C8-HSL组产生的生物量约为对照组的6倍;经添加C6-HSL和N-3-oxo-C8-HSL处理的养殖水体中,亚硝酸盐最终浓度比对照组低28.6%,但无机磷浓度稍高。数据因子分析结果表明,实验过程中(9～27 d),添加AHLs信号因子C6-HSL和N-3-oxo-C8-HSL两组养殖水体内环境的总体得分较高,说明养殖水体的内环境处于较好状态。     

环境因素对长寿湖底泥释磷影响的模拟实验研究

肥水养殖显著增加了长寿湖底泥中的磷含量。为了解肥水养殖积累在湖泊底泥中磷的释放情况,以长寿湖大坝口枯水期底泥为实验材料,模拟研究了不同环境条件(上覆水pH、温度、DO含量和扰动)下湖泊底泥的释磷特征。结果表明,在弱碱性条件下,底泥释磷量随上覆水pH的升高而升高;温度升高有利于底泥磷的释放,温度每升高5℃,第21天时底泥释磷量增大0.0045～0.0074 mg/L;DO含量降低有利于底泥中铁/铝结合态磷的释放;扰动对底泥磷的释放没有明显影响。研究表明,网箱养殖增加了底泥中的有机磷含量,促进有机磷向无机磷转化,增大了底泥中磷的释放风险。     

连片生态浮床对微污染河水的净化效果

选取漕桥河的支流庙尖浜作为实验河段,以睡莲(Nymphaea alba)、菖蒲(Acorus calamus Linn)和水芹(Oenan-the javanica(Blume)DC)作为微污染水体净化的浮床植物,研究连片生态浮床的净化能力随季节的变化和浮床面积对连片生态浮床净化能力的影响。结果显示,秋-冬-春季节内植物的净化能力随季节变化呈"U"型,相应的河水水质的变化呈一个倒置的"U"型;在一定营养负荷和植物正常生长状况下,沿水流方向,氮、磷含量随浮床面积的增加而降低——春季时,随浮床面积增加,菖蒲区对TN的去除率由8.6%增加到26.7%,TP的去除率由17.1%增加到58.2%,水芹区对TN和TP的去除率最高可达22.0%和28.0%。研究表明连片生态浮床是河道水质改善的有效可行的方法之一,可为太湖入湖河流的营养物质控制提供科学依据。     

不同来源高浓度有机废水的集中处理

按照水质情况,将多种来源于不同工业生产过程中的高浓度有机废水划分为高悬浮固体乳化液废水、难生化高浓度有机废水、高悬浮固体不含油有机废水、含铬有机废水和杂质含量较少的乳化液废水5类,分别采用酸化破乳/Fen-ton氧化/混凝/絮凝、Fenton氧化/混凝/絮凝、混凝/絮凝、还原/混凝/絮凝、震动膜过滤技术作为生化预处理技术,并通过小试和中试验证了各技术的效果。实验结果表明,按照上述分类结果,采用不同预处理技术可以得到良好的效果,废水水质明显改善,满足继续生化处理的基本条件。各预处理生产装置处理效果稳定,同时生化系统已经稳定运行120天以上,COD去除率超过90%,出水经过低剂量的Fenton试剂处理后可达到《污水排入城镇下水道水质标准》(CJ343-2012)。     

Parental phenols exposure and spontaneous abortion in Chinese population residing in the middle and lower reaches of the Yangtze River

Widespread use of phenols has led to ubiquitous exposure to phenols. In experimental animals, phenols increased resorptions, reduced live litter size and fetal body weights. However, there are limited epidemiological evidences of the relationships between exposure to phenols and pregnancy outcomes. We evaluated the associations between parental urinary levels of various phenols and spontaneous abortion in a Chinese population residing in the middle and lower reaches of the Yangtze River. A case-control study was conducted that included 70 case couples with medically unexplained spontaneous abortion and 180 control couples who did not have a history of spontaneous abortion and had at least one living child. Both parental urinary phenols were measured by ultra-high performance liquid chromatography-tandem mass spectrometry including bisphenol A (BPA), benzophenone-3 (BP-3), 2,3,4-trichlorophenol (2,3,4-TCP), pentachlorophenol (PCP), 4-n-octylphenol (4-n-OP) and 4-n-nonylphenol (4-n-NP). Compared with the low exposure group, there was an increased risk of spontaneous abortion with high paternal urinary PCP concentration [odds ratio (OR) = 2.09, 95% Confidence Interval (CI), 1.05–4.14], and maternal exposure to 4-n-OP and alkylphenol(s) also significantly increased the risk of spontaneous abortion (OR = 2.21, 95% CI, 1.02–4.80; OR = 2.81, 95% CI, 1.39–5.65, respectively). Our study firstly provides the evidence that paternal PCP exposure, maternal 4-n-OP and alkylphenol(s) exposure are associated with spontaneous abortion in humans.     

Detection of transfluthrin and metofluthrin genotoxicity in the ST cross of the Drosophila Wing Spot Test

In this study, different concentrations of transfluthrin and metofluthrin have been assayed for genotoxicity by using the Wing Spot Test on Drosophila melanogaster. Standard cross was used in the experiment. Third-instar larvae that were trans-heterozygous for the two genetic markers mwh and flr³ were treated at different concentrations (0.0103 mg mL⁻¹, 0.103 mg mL⁻¹ for transfluthrin and 6 μg mL⁻¹, 60 μg mL⁻¹ for metofluthrin) of the test compounds. Feeding ended with pupation of the surviving larvae and the genetic changes induced in somatic cells of the wing’s imaginal discs lead to the formation of mutant clones on the wing blade. Results indicated that two experimental concentrations of transfluthrin and 60 μg mL⁻¹ metofluthrin showed mutagenic and recombinogenic effects in both the marker-heterozygous (MH) flies and the balancer-heterozygous (BH) flies.