一体化氧化沟处理污水的试验

本文设计开发了一种新型的一体化沟系统，对其进行了清水模拟试验和污水处理试验。清水试验结果表明，这种一体化氧化沟内沉淀池具有良好的固液分离特性，当水力停留时间大于１２小时，沟内ＳＳ在２－５ｇ／ｌ时，出水ＳＳ均小于５０ｍｇ／ｌ，出水ＳＳ相对于沟内ＳＳ的去除率大于９８％。污水试验结果表明，系统有较强的去除有机物的能力，当水力停留时间为２１小时时，ＣＯＤ去除率可达８０％以上，ＢＯＤ５去除率在９０％以上。出     

氧化沟基本特性的剖析

氧化沟既不是完全混合反应器，也不是推流反应器。它是一种连续环路反应器(continuous Loop Reactor，简称CLR)。目前，氧化沟作为一项废水处理技术已被广泛地重视和应用。本文从曝气和混合、反应动力学以及水力学等方面剖析氧化沟和连续环路反虚器的基本实质，论述各种类型氧化沟的一些共同特征，以有利于在氧化沟设计中对若干基本原则的理解和掌握。     

改性聚丙烯填料水处理性能试验研究

采用化学氧化-铁离子覆盖技术对普通聚丙烯填料进行改性，并对改性前后的填料进行生物亲水性、表面特性、临界表面张力以及模拟污水的生物挂膜等特性研究。结果发现，改性填料的亲水性和表面粗糙度大大提高，临界表面张力变大，表面电性为正，在生物膜法水处理中，其挂膜速度提高了46.7%，终期氨氮去除率提高了8.84%。可见改性填料与普通填料相比，其水处理性能较好。     

生物膜处理城市河道污染水体的挂膜试验研究

以城市河道污染水体为研究对象,通过水体中土著微生物的富集过程,利用自行设计的生物接触氧化装置进行动态挂膜试验研究.讨论了挂膜过程系统对污染物去除效果的变化、生物膜及其生物相的变化;同时考察了填料上SS以及VSS的变化;分析了影响填料挂膜的各种因素,提出了判断生物膜成熟的依据.     

Carrousel氧化沟的流动特性研究

采用颗粒动态分析仪（PDA）对倒伞形表面曝气机曝气的Carrousel小试氧化沟进行测试，得出了氧化沟内较系统的流动特性参数。比较了固液两相在氧化沟内流动的差别，发现固液两相流动速度差别较小，由于惯性的影响，固相的沉降速度略大于液相。考察了表曝机的转速、表曝机相对于液面的位置、氧化沟的深度等因素对氧化沟内流动的影响，随着表曝机转速的增大和表曝机浸入液面深度的增加，流动速度和沉降速度均会增大，而氧化沟深度增加时，距离液面同一深度处的速度则会减小。实验结果与污水处理厂的实际情形进行比较发现，二者变化趋势一致，说明本实验结果可用于指导工程实际，为氧化沟的优化设计提供依据。     

污水厂Carrousel氧化沟溶解氧和速度分布的研究

对长沙某污水处理厂的Carrousel氧化沟进行现场测试，获得不同截面的溶解氧和速度的数据，探讨了表曝机台数、沟深、沟的长宽比、进出水位置对溶解氧和速度的影响。初步掌握了该Carrousel氧化沟内溶解氧和速度的变化规律，认为通过调节倒伞形表面曝气机，可以在沟内不同区段创造好氧与缺氧的环境，为最终实现同步硝化反硝化的高效运行做准备。     

用于生物接触氧化工艺的填料特性比较研究

填料材质、结构等影响到生物膜的性状和水力学特性，是决定生物接触氧化工艺处理效果的关键因素。本文分别选取了悬挂式填料和悬浮式填料各2种填料，分别从COD与NH2-N的去除、充氧效率和出水浊度等方面对各种填料处理城市污水进行了比较研究。实验结果表明，悬挂式填料具有挂膜快、处理效果稳定，受环境变化影响较小；悬浮式填料受气水作用能够悬浮转动而具有较强的布水、布气功能；生物量的差异导致悬浮式填料和悬挂式填料处理效果和充氧效率不同，悬浮式填料生物膜容易脱落导致系统受负荷冲击时生物量流失而处理效果变差；软性填料生物膜容易板结成球，容易导致其处理效果降低。     

卡鲁塞尔氧化沟流速与水质组分分布的现场测试

通过实测卡鲁塞尔氧化沟不同位置处流速与水质组分，分析了流速对沟内污泥、溶解氧浓度的影响以及溶解性组分的微生物转化规律。结果表明，溶解氧与流速呈正相关、污泥浓度（MLSS）与流速呈负相关；水质组分在沟中不同区段呈现出各自特点，反映了COD、氨和磷酸盐的生物转化历程；流速也是影响溶解性组分混合的重要因素，改善进水口附近混合液的流场，提高局部流速有利于缩短进水组分均布的距离。     

用于生物接触氧化工艺的填料特性比较研究

填料材质、结构等影响到生物膜的性状和水力学特性 ,是决定生物接触氧化工艺处理效果的关键因素。本文分别选取了悬挂式填料和悬浮式填料各 2种填料 ,分别从COD与NH3 N的去除、充氧效率和出水浊度等方面对各种填料处理城市污水进行了比较研究。实验结果表明 ,悬挂式填料具有挂膜快、处理效果稳定 ,受环境变化影响较小 ;悬浮式填料受气水作用能够悬浮转动而具有较强的布水、布气功能 ;生物量的差异导致悬浮式填料和悬挂式填料处理效果和充氧效率不同 ,悬浮式填料生物膜容易脱落导致系统受负荷冲击时生物量流失而处理效果变差 ;软性填料生物膜容易板结成球 ,容易导致其处理效果降低     

日本的氧化沟技术

本文结合笔者在日本的技术考察，介绍了日本采用氧化沟技术的现状，设计标准，以及引进氧化沟成套设备等情况，最后结合我国国情提出了希望。     

A rapid, sensitive screening test for polycyclic aromatic hydrocarbons applied to Antarctic water

We describe a rapid, sensitive, fluorescence screening test for polycyclic aromatic hydrocarbons in water samples that avoids more costly time-consuming methods. The screening test works by detecting benzo[a]pyrene. It runs without the need for any pre-concentration step, thus rendering it suitable for routine use in water-quality-control laboratories. The test recognizes contaminated samples rapidly (150 s) and inexpensively with a cut-off level of 10 ng l(-1), which is the value that the European Union and World Health Organization (WHO) have laid down in its assessment of the quality of water for human consumption. This was first ascertained by analysing tap and waste-water samples before studying environmental water samples from the Antarctic region. The reliability of the screening test was 2% false positives and 4% false negatives in 200 samples of tap and waste-water. The applicability was confirmed by the fact that the predictions of the screening test coincided exactly with results obtained with gas chromatography-mass spectrometry assays. We also discuss the polluted Antarctic samples and the possible sources of the contamination involved.     

Investigation of various physicochemical and environmental parameter influence on pesticide sorption to ditch bed substratum by means of experimental design

Diffuse pollution by pesticide applied in rural catchments may contribute to alter water quality. Besides actions relative to the way the substances are introduced into the environment, it is also possible to limit the contamination by interfering on their transfer pathways from fields to the main river network. Especially, interface areas such as buffer strips or small ditches may play a major part in pesticide diffuse pollution decrease. In ditches a great variety of materials may act as sorbents for organic contaminants: grass, leaves, wood debris or sediments. In this study, laboratory experiments were designed to determine sorption characteristics for three herbicides with different physicochemical properties on sediment and leaves in decay commonly found in agricultural ditches. Sorption capacities were assessed for the herbicides isoproturon, diuron and diflufenican.

Experimental design was carried out to investigate the effects of five parameters on herbicide sorption on sediment and dead leaves. These parameters have been chosen according to parallel field experiment needs. Thus, the influence of initial sorbent moisture, herbicide form, i.e. active substance or commercial formulation, water quality (tap or natural ditch water), bromide ions (used as conservative tracers) and solid/liquid ratio have been tested. Within the parameters investigated, pesticide formulation and solid/liquid ratio were the most important parameters affecting pesticide sorption on both ditch materials.     

外循环厌氧处理工艺中布水和三相分离的改进研究

污水处理中的布水设备和三相分离设备存在很多缺点,通过旋流配水装置和传统配水装置、小间距斜板三相分离装置和传统三相分离装置的比较试验,研究了旋流配水装置和小间距斜板三相分离装置的性能.研究结果表明:在相同膨胀率的条件下,旋流配水装置所需的回流量小,能耗相对较少;在水力上升流速为8 m/h时,采用旋流配水装置进水时,污泥分布曲线较平缓,污泥在高度上分布较均匀,而采用传统配水装置进水时,污泥主要分布在反应器底部,污泥浓度分布不均匀;在上升流速相同的情况下,采用小间距三相分离装置的反应器出水携带的颗粒污泥浓度较小;在相同的进水COD浓度时,小间距三相分离装置分离的沼气量较多.改进的布水和三相分离装置的性能明显优于传统的布水和三相分离装置.     

Evaluation of Acacia nilotica (L.) del. and Casuarina equisetifolia forst. for tolerance and growth on microbially treated dyestuff wastewater

Two tree species, Acacia nilotica (L.) Del. and Casuarina equisetifolia Forst., were tested for their tolerance and growth on dyestuff wastewater containing phenol, aniline, and methyl violet. The wastewater was treated microbially by using a culture of Pseudomonas alcaligenes in a fixed-film bioreactor. The plants were watered with untreated and treated wastewater and tap water (control) at the rate of 2 litre per plant per week. A. nilotica exhibited 100% survival with both untreated and treated wastewater, and growth (increase in height) was comparable to that of control plants. However, growth of C. equisetifolia was adversely affected. It exhibited 100% survival with treated wastewater but only 87% survival with untreated waste-water and the percentage increase in height was less with both treated and untreated wastewater. There was no effect on soil except for an increase in chloride content.     

Novel polymer monolith microextraction using a poly-(methyl methacrylate-co-ethylene dimethacrylate) monolith and its application to the determination of polychlorinated biphenyls in water samples

A novel and simple method based on polymer monolith microextraction (PMME) coupled to gas chromatography with electron-capture detection (GC-ECD) was developed for the determination of six polychlorinated biphenyls (PCBs) residues in water samples. The proposed method used poly-(methyl methacrylate-co-ethylene dimethacrylate) (MMA-co-EDMA) monolith as extraction media. Several factors affecting experiments such as sample flow rate, sample volume, the type of eluent, eluent volume, eluent flow rate, effect of salt addition and carry over effect were investigated and optimized systematically. The limits of detection (LODs) for six PCBs were 0.028-0.043 ng mL⁻¹ in water samples. The intra-day and inter-day precisions (R.S.D.) were less than 9.2% and 9.6%, respectively. The proposed method was successfully applied to the determination of six PCBs in tap water, lake water and industrial waste water and the trueness has been evaluated by recovery experiments. The obtained relative recoveries were in the range of 63.3-105.6%.     

The mutagenic potentials of tap water samples in Shanghai

The tap water samples were collected from the users' ends in several areas of Shanghai, which is located in Taihu Lake basin, Eastern China. Source water samples were also collected from two municipal source water facilities at the same time. Samples were assayed by three different short-term mutagenicity test systems: Salmonella/microsome assay (Ames test), the Arabinose resistance test (Ara test) and the SOS/umu test. The data showed that two source water samples did not display direct mutagenic potentials. Two tap water samples from city north, which were directly from Yangtze River, were also not mutagenic. Water samples from city south and middle which used source water originating from Taihu Lake were proved to be contaminated with mutagenic potentials by three different assay techniques. The boiled water displayed an even stronger mutagenic potential compared to its original tap water. The molecular mechanism of mutagenicity was associated with a reading frame-shifting potential. GC-MS analysis of tap water extracts from city middle and corresponding source water was compared. Qualitatively similar spectra were observed except for the peaks of three chlorinated aromatic hydrocarbon compounds, which existed only in the tap water. Since the water source has been polluted, raw water was heavily chlorinated in order to sterilize. More toxic compounds, including mutagens, might form during the multi-chlorination. Caution about the possibility of elevated cancer risks in the population that consumes heavily chlorinated water should be kept in mind. A cohort study in the residents of Shanghai is required.     

A level change in mutagenicity of Japanese tap water over the past 12 yr

A relative comparison study of mutagenicity in Japanese tap water was conducted for 1993 and 2005 surveys. It intended to assess the effects of advanced water treatment installations to water works, improvement of raw water quality and improvement of residual HOCl concentration controlling. Sampling points (taps) were the same in both surveys. The results of 245 samples obtained by the Ames Salmonella mutagenicity test (Ames test) were analyzed. The Ames tests were conducted by using Salmonella typhimurium TA98 and TA100 strains with and without exogenous activation (S9). With the exception of TA100-S9, the other conditions needed no discussion as a factor in the mutagenicity level change. The average mutagenicity in 1993 and 2005 under the conditions of TA100-S9 were 2600 and 1100 net revertant L⁻¹, respectively. This indicated that the mutagenicity level of Japanese tap water decreased during the 12-yr period. Particularly a remarkable decrease in mutagenicity was observed in the water works where the advanced water treatments were installed during the 12-yr period. The advanced water treatments were effective in decreasing the mutagenicity of tap water. Mutagenicity also decreased in the water works with conventional water treatments; the improvement of residual HOCl concentration controlling was also considered to be effective in decreasing the mutagenicity of tap water.     

The transfer of trichloroethylene (TCE) from a shower to indoor air: experimental measurements and their implications

Experiments were performed to measure the transfer of trichloroethylene (TCE), a volatile organic compound (VOC), from tap water in showers to indoor air. In these experiments, the loss of TCE from tap water in the shower is based on the difference between influent and effluent concentrations. We have developed and previously published a three-compartment model, which we use to simulate the 24-h concentration history of VOCs in the shower, bathroom, and remaining household volumes resulting from the use of contaminated tap water. An important input to this model is the transfer efficiency of the VOC from water to air. The experiments reveal that the transfer efficiency of TCE from shower water to air has an arithmetic mean value of 61 percent and an arithmetic standard deviation of 9 percent. Analysis of the results shows that there is no statistically significant difference between the transfer efficiency measured with hot (37 degrees C) or cold (22 degrees C) shower water and that there is no statistically significant change in transfer efficiency with time during a 20-min shower. The implications for exposure assessment are considered.     

The transfer of trichloroethylene (TCE) from a shower to indoor air: experimental measurements and their implications

Experiments were performed to measure the transfer of trichloroethylene (TCE), a volatile organic compound (VOC), from tap water in showers to indoor air. In these experiments, the loss of TCE from tap water in the shower is based on the difference between influent and effluent concentrations. We have developed and previously published a three-compartment model, which we use to simulate the 24-h concentration history of VOCs in the shower, bathroom, and remaining household volumes resulting from the use of contaminated tap water. An important input to this model is the transfer efficiency of the VOC from water to air. The experiments reveal that the transfer efficiency of TCE from shower water to air has an arithmetic mean value of 61 percent and an arithmetic standard deviation of 9 percent. Analysis of the results shows that there is no statistically significant difference between the transfer efficiency measured with hot (37 degrees C) or cold (22 degrees C) shower water and that there is no statistically significant change in transfer efficiency with time during a 20-min shower. The implications for exposure assessment are considered.     

The Transfer of Trichloroethyene (TCE) from a Shower to Indoor Air: Experimental Measurements and Their Implications

Experiments were performed to measure the transfer of trlchloroethylene (TCE), a volatile organic compound (VOC), from tap water In showers to Indoor air. In these experiments, the loss of TCE from tap water in the shower is based on the difference between Influent and effluent concentrations. We have developed and previously published a three-compartment model, which we use to simulate the 24-h concentration history of VOCs in the shower, bathroom, and remaining household volumes resulting from the use of contaminated tap water. An important input to this model is the transfer efficiency of the VOC from water to air. The experiments reveal that the transfer efficiency of TCE from shower water to air has an arithmetic mean value of 61 percent and an arithmetic standard deviation of 9 percent. Analysis of the results shows that there Is no statistically significant difference between the transfer efficiency measured with hot (37°C) or cold (22°C) shower water and that there Is no statistically significant change In transfer efficiency with time during a 20-mln shower. The implications for exposure assessment are considered.