不同处理工艺对牛仔布生产废水中壬基酚去除效果研究

壬基酚(NP)作为非离子表面活性剂壬基酚聚氧乙烯醚(NPEOs)的降解产物,由于具有的内分泌干扰特性备受关注。研究了印染废水处理中普通活性污泥法、氧化沟以及接触氧化3种工艺对废水中壬基酚的去除效果。结果表明:泥龄较短的处理工艺对壬基酚具有明显的去除效果,印染废水的高碱性和其含有的特殊染料对壬基酚去除没有产生负面影响;其中普通活性污泥法去除率较好,平均去除率为91%,其次为氧化沟工艺,平均去除率为80%,接触氧化工艺去除率偏低,仅为41%,接触氧化法相对较长的泥龄不利于壬基酚的去除。     

纳滤膜去除饮用水中PPCP研究进展

个人药品(PPCP或PhACs)是继杀虫剂、除草剂及内分泌干扰物之后发现的水体中普遍存在的痕量有机物,具有难降解性、生物积累性和长期危害性,其对环境造成的危害正逐渐引起人们的关注.结合国内外最新研究成果,介绍纳滤膜去除饮用水中PPCP的作用机理及影响因素,并展望今后研究方向.     

利用纳米材料吸附去除饮用水中砷(Ⅴ)的研究

研究纳米材料对人工配水中砷(Ⅴ)吸附去除的规律和影响因素,为研制新型除砷材料提供一定的理论依据。分别选取不同的纳米材料和常规除砷材料,利用静态试验对人工配水中砷(Ⅴ)进行去除效果的比较,并探讨环境因素对去除效果的影响。结果表明纳米材料的除砷效果优于常规除砷材料,试验中纳米ZnO的除砷效果较好,接触0.5 h后去除率即可达到99.9%,去除效果受温度、pH和常见阴离子Cl-、SO24-影响小。纳米ZnO对水中砷(Ⅴ)的去除效果较好,经过进一步的研究有望应用于饮水除砷(Ⅴ)。     

再生水景观水体色度和臭味控制研究

对再生水景观水体的色度和臭味进行测定,分析DePAT(R)系统对其色度和臭味的处理效果.研究结果表明,DePAT(R)系统中旁滤单元对色度有较强的去除能力,但湖水中色度仍出现积累,这主要是由于藻类和悬浮物所引起的;DePAT(R)系统对臭味物质MIB、IPMP、TCA均具有很强的去除能力.     

纳滤膜去除水中药品和个人护理品的研究进展

药品和个人护理品(PPCPs)是继持久性有机污染物(POPs)及内分泌干扰物(EOCs)之后发现的水体中普遍存在的痕量有机物,它的难降解性、生物毒性积累和长期危害性,对环境和生态系统造成的危害正逐渐引起科学界的关注。通过对国内外最新研究成果的分析,介绍了纳滤膜去除水中PPCPs的优势所在,以及去除过程的作用机理和影响因素,并对今后研究方向做了展望。     

曝气生物滤地在污水回用中去除氨氮的试验研究

采用曝气生物滤地(BAF)工艺处理某污水处理厂模拟二级出水,研究了水力负荷及滤料层高度对NH_3-N去除效果的影响.试验结果表明,当进水NH_3-N≤25 mg/L时,平均NH_3-N去除率达到93.12%,出水NH_3-N可降至3 mg/L以下.当水力负荷为1.44 m~3/(m~2·h),HRT为1.8 h时,氨氮的去除效果最好,去除率达到95.32%,出水NH_3-N在1.5 mg/L以下.BAF对NH_3-N的去除作用主要发生在滤料的中上层.     

三维电极-铁屑内电解-水解酸化-BAF工艺处理火炸药废水的研究

针对火炸药废水毒性大、硝基化合物浓度高、CODCr高、可生化性差的特点,采用三维电极(OFR)-铁屑内电解-水解酸化-BAF工艺对火炸药废水进行中试研究.研究结果表明,此工艺不但能够稳定去除CODCr,且能高效去除硝基化合物,其对CODCr和硝基化合物的去除率分别为96.9%和99.6%.出水水质符合<兵器工业水污染物排放标准(火炸药)>(GB 14470-2002)要求,且系统运行稳定,抗冲击负荷能力强.     

北京城市河湖水质净化组合工艺中MIEX投加方式的影响研究

采用磁性离子交换树脂(MIEX)—混凝(PAC)—膜(MF)的联合工艺进行再生水回补型城市河湖地表水净化研究,考察了磁性离子交换树脂投加条件对主要污染物的去除效果。结果表明:MIEX的混合速度为500 r/min,反应时间为30 min,沉淀时间为20 min时,MIEX—PAC—膜的联合工艺对水中TP、TN、叶绿素a和浊度的去除率分别为66.67%、69.62%、76.51%和96.70%。此外,组合系统对COD、DOC和UV254等表征有机物含量的指标的去除率达到了68.00%、40.53%和58.77%,实现了对不同分子量区间内有机物的完整去除。     

离子交换法去除原水中六价硒的研究

就离子交换法去除原水中硒(Ⅵ)进行了研究。研究结果表明,采用201×7强碱性阴离子交换树脂去除水中硒(Ⅵ)时,当原水硒(Ⅵ)为100μg/L,硒(Ⅵ)的去除率可达96%以上,出水硒浓度完全满足现行《生活饮用水水质标准》中对硒含量的规定。采用离子交换法除硒(Ⅵ)具有高效、操作简便等特点。     

黄浦江原水NDMA前体物的组成规律及其在常规净水工艺中的削减特性

研究了黄浦江上游水源的二甲基亚硝胺(NDMA)前体物的组成规律,并以某水厂常规净水工艺为研究对象,考察了其在水厂工艺单元中的削减特征。研究发现:黄浦江水中NDMA前体物主要以相对分子质量小于1 000和亲水性组分为主,其组成规律基本与溶解性有机氮(DON)一致,有效控制水中DON的含量是控制NDMA产生的重要方法;常规处理工艺中沉淀、过滤和消毒等整体工艺可削减NDMA生成潜能,但总体对生成潜能的削减不足原水NDMA生成潜能的50%,无法有效去除水中NDMA前体物,且对其他亚硝胺类NDEA、NPIP和NDBA等的前体物去除效果均小于52%。     

LC-MS-(MS) determination of oxidative degradation products of nonylphenol ethoxylates, carboxylates and nonylphenols in water.

A commercial blend of nonylphenol ethoxylates (NPEOs) was chosen as representative for non-ionic polyethoxylated surfactants to study the oxidative degradation of this class of surfactants in water using ozonation as well as electron beam irradiation with and without the addition of ozone as treatment processes. The electron beam irradiation processes applied represent so-called Advanced Oxidation Processes (AOPs); the combined ozone/electron beam irradiation is, moreover, the most powerful AOP which can be applied in aqueous systems. It was found that both ozonation and the two AOPs applied were able to decompose not only the NPEOs but also the polyethyleneglycoles (PEGs) formed as by-products from NPEO degradation to residual concentrations below the limit of detection. Moreover, the treatment processes were also used to study the oxidative degradation of nonylphenoxy acetic acid (NPEC) and of nonylphenol (NP) which are formed as by-products from biodegradation of NPEOs.     

饮用水中典型含氮消毒副产物二氯乙腈的研究进展

二氯乙腈(DCAN)是氯化消毒过程中产生的一种含氮消毒副产物(NDBPs)。DCAN具有强烈的遗传毒性和致突变性,逐渐引起人们的广泛关注。结合国内外最新研究成果,介绍了DCAN的分析方法,以及影响其产生的因素,并对今后的研究方向进行了展望。     

PDM复合混凝剂处理春季嘉陵江水的应用研究

通过小试考察了聚二甲基二烯丙基氯化铵(PDM)复配硫酸铝(AS)、氯化高铁(FC)、聚氯化铝(PAC)和聚硫酸铁(PFS)以及单独采用PAC处理某水厂春季嘉陵江水源水的效果,选择了复配比例为1:100的PAC-PDM复合混凝剂处理该时期原水。通过对矾花与沉降性能的研究,发现复配比例越低,投药量越少,矾花粒径越小。当矾花粒径达到0.5 mm以上时,矾花的沉降性能较好,且矾花的沉降性能还与矾花的密实程度有很大关系。通过对PAC和PAC-PDM连续生产对比试验研究,在出厂水满足《生活饮用水卫生标准》(GB 5749—2006)要求的情况下,PAC-PDM和PAC的平均投药量分别约为8mg/L和14.3mg/L,在春季该水厂采用PAC-PDM处理嘉陵江原水较单独采用PAC约节省30%混凝剂费用。     

Analysis of nonylphenol polyethoxylates and their metabolites in water samples by high-performance liquid chromatography with electrospray mass spectrometry detection.

Evidence that some alkylphenol polyethoxylates (APEOs) breakdown products are estrogenic has intensified the interest over their environmental and human health effects. Different quantitative methods but one single preparation and extraction method for the analysis of nonylphenol polyethoxylates (NPEOs) and their metabolites in water samples using solid-phase extraction (SPE) and high-performance liquid chromatography (HPLC) with electrospray mass spectrometry detection (ESI-MS), are described. Quantification limits range about the low ng/l for the enrichment of 500 ml water samples and mean recoveries of 70% are achieved. These methods were subsequently applied to water samples coming from Austrian treatment plants.     

Disinfection by-products and microbial contamination in the treatment of pool water with granular activated carbon.

For swimming pools, it is generally agreed that free chlorine levels have to be maintained to guarantee adequate disinfection. Recommended free chlorine levels can vary between 0.3 and 0.6 mg/L in Germany and up to 3 mg/L in other countries. Bathers introduce considerable amounts of organic matter, mainly in the form of such as urine and sweat, into the pool water. As a consequence, disinfection byproducts (DBPs) are formed. Regulations in Germany recommend levels of combined chlorine of less than 0.2 mg/L and levels of trihalomethanes (THMs) of less than 20 microg/L. Haloacetic acids (HAAs), haloacetonitriles (HANs), chloropicrin and chloral hydrate are also detected in considerable amounts. However, these compounds are not regulated yet. Swimming pool staff and swimmers, especially athletes, are primarily exposed to these byproducts by inhalation and/or dermal uptake. In Germany, new regulations for swimming pool water treatment generally require the use of activated carbon. In this project, three different types of granular activated carbon (GAC) (one standard GAC, two catalytic GACs) are compared for their long time behaviour in pool water treatment. In a pilot plant operated with real swimming pool water, production and removal of disinfection byproducts (THMs, HAAs, AOXs), of biodegradable substances (AOC), of bacteria (Pseudomonas aeruginosa, Legionella, coliforms, HPC) as well as the removal of chlorine and chloramines are monitored as function of GAC bed depth. Combined chlorine penetrates deeper in the filter bed than free chlorine does. However, both, free and combined chlorine removal efficiencies decrease over the time of filter operation. The decreases of removal efficiencies are also observed for parameters such as dissolved organic carbon, spectral absorption coefficient, adsorbable organic carbon and most of the disinfection byproducts. However, THMs, especially chloroform are produced in the filter bed. The GAC beds were contaminated microbially, especially with P. aeruginosa. The contamination was not removable by backwashing with chlorine concentrations up to 2 mg/l free chlorine.     

Evaluation of Chlorine Decay in Drinking Water Systems for Different Flow Conditions: From Theory to Practice

An intensive study was developed to assess the influence of different flow conditions in the chlorine decay of drinking water systems based on a series of experiments tested on a loop pipe linked to the Lisbon water distribution system. Water samples and chlorine measurements were taken under three distinct flow conditions: (1) steady-state regimes; (2) combined flow situations—an initial steady-state period, followed by successive transient events and a new steady-state period; (3) isolated flow tests—steady-state flow regimes and transient flow regimes performed independently. All the tests were replicated for a typical range of Reynolds numbers in real water distribution systems. More specifically, pressure and velocity variations associated with hydraulic transients or water hammer conditions may degrade water quality. The series of results obtained in steady-state flow conditions confirmed the rate of chlorine decay increases with the Reynolds number and provided evidence that hydraulic transients have a slowing-down effect on chlorine decay rates.     

南水北调中线干线水体特征指标筛查与动态分析

为掌握南水北调总干渠的水体特征指标情况，对中线干渠 12 个断面的 99 项水化学指标和 5 项同位素指标 在 2020—2021 年度的变化情况进行系统分析，按照可以在干渠沿线普遍检出并能广泛使用（普适性）、干渠本身 指标稳定（稳定性）、与周围水体有明显差异（差异性）的原则，建立干线水体特征指标体系，尝试识别出总干渠的 特征指标，进而评估特征指标的正常动态范围，以期为快速研判南水北调干渠边坡渗水、漏水等问题提供技术支 撑。研究结果表明：对于“普适性”，中线干渠水体有 10 项水化学指标可以满足；对于“稳定性”，中线干渠水体中 锶、钠、钾、钙、镁和氯等 8 项水化学指标总体稳定，受季节变化影响具有一定的波动性，氘（ 2H）、氧（ 18O）、锶（ 87Sr）和 硫（ 34S）同位素具有较好的稳定性，受季节影响较小；对于“差异性”，氯和钠两项单项指标及氯/镁离子比、钠/镁离 子比与周围水体差异最为显著。结合多项原则和影响因素进行综合考虑，最终选定氯、钠、锶、氯/镁离子比、钠/ 镁离子比以及氘（ 2H）、氧（ 18O）、锶（ 87Sr）共 8 项指标作为具有普适性、稳定性和差异性的特征指标。发现边坡渗 水的第一时间，可以采用氯、钠、氯/镁离子比、钠/镁离子比以及氘（ 2H）、氧（ 18O）等6 项特征指标为快速分析研判提供支撑。     

强化混凝技术处理南淝河污染水的效果

选用聚合氯化铁(PFC)、聚合硫酸铁(PFS)、聚合氯化铝(PAC)和聚合氯化铝铁(PAFC)作为混凝剂;选用阳离子型聚丙烯酰胺(CPAM)、阴离子型聚丙烯酰胺(APAM)和非离子型聚丙烯酰胺(NPAM)作为助凝剂,通过室内试验对比研究强化混凝技术中多种混凝剂单用及其和助凝剂联用对南淝河污染水的除浊和去污效果,并用于南淝河现场构建的混凝沉淀系统。结果表明,4种混凝剂单用时,PAFC对浊度、TP去除效果最优,对CODMn有良好的去除效果,且不影响原水的p H值,而PFC和PFS单用时可明显降低原水p H值,4种混凝剂单用时对TN均没有明显去除效果;PAFC与CPAM联用时对浊度的去除效果最佳,明显优于PAFC与APAM和NPAM联用和PAFC单用的效果;混凝剂与CPAM联用提高了其除浊和去除TP的能力,但不能明显改善其去除CODMn的效果,对原水p H和TN的影响与单用时相同。选取"PAFC+CPAM"作为南淝河示范工程的混凝剂和助凝剂,现场混凝沉淀出水水质稳定,浊度和TP的去除效果较好,去除率分别达到90%和80%,对CODMn的去除率约为52%,而对TN的去除效果有限,去除率约为22.4%。     

基于PLSR的珠江口城市河流水质高光谱反演

为研究珠江口城市河流水体高光谱特征与城市河流水质指数(CWQI)的关系,对中山市典型河流开展了高光谱监测和同步水质分析,基于偏最小二乘回归(PLSR)建立了高光谱数据与CWQI的反演模型,并研究了反演模型的最佳光谱分辨率和最优主成分数。结果表明：基于化学需氧量、总磷、氨氮和溶解氧4项水质指标质量浓度值计算得到的CWQI值可较好地反映研究区河流水质状况;水体不同波段的光谱反射率与CWQI存在一定的相关性,可用于区分不同CWQI的水体;光谱分辨率为50nm、提取主成分数为8时的反演模型效果最优,验证集均方根误差和平均相对误差分别为0-768和18-1%。将该反演模型与无人机高光谱监测数据结合,可较好地反映河流水质的空间差异。     

LARGE-EDDY AND DETACHED-EDDY SIMULATIONS OF THE SEPARATED FLOW AROUND A CIRCULAR CYLINDER

The separated turbulent flow around a circular cylinder is investigated using Large-Eddy Simulation (LES), Detached-Eddy Simulation (DES, or hybrid RANS/LES methods), and Unsteady Reynolds-Averaged Navier-Stokes (URANS). The purpose of this study is to examine some typical simulation approaches for the prediction of complex separated turbulent flow and to clarify the capability of applying these approaches to a typical case of the separated turbulent flow around a circular cylinder. Several turbulence models, i.e. dynamic Sub-grid Scale (SGS) model in LES, the DES-based Spalart-Allmaras (S-A) and k ? ω Shear-Stress-Transport (SST) models in DES, and the S-A and SST models in URANS, are used in the calculations. Some typical results, e.g., the mean pressure and drag coefficients, velocity profiles, Strouhal number, and Reynolds stresses, are obtained and compared with previous computational and experimental data. Based on our extensive calculations, we assess the capability and performance of these simulation approaches coupled with the relevant turbulence models to predict the separated turbulent flow.