水和废水中阴离子表面活性剂测定干扰因素试验研究

对二氮杂菲萃取分光光度法测定水和废水中阴离子表面活性剂的主要干扰因素进行了试验研究.设计了温度过低、浑浊带色和混溶乳化3种干扰试验方案,探讨了各干扰因素在不同工况下的试验结果、影响程度及消除措施.提出温度过低须在测定前提高环境温度,以确保显色反应完全;浑浊带色须在测定中采用色(浊)度校正法消除干扰;混溶乳化可在测定中利...     

Statistical evaluation of photon count rate data for nanoscale particle measurement in wastewaters

The dynamic light scattering (DLS) technique can detect the concentration and size distribution of nanoscale particles in aqueous solutions by analyzing photon interactions. This study evaluated the applicability of using photon count rate data from DLS analyses for measuring levels of biogenic and manufactured nanoscale particles in wastewater. Statistical evaluations were performed using secondary wastewater effluent and a Malvern Zetasizer. Dynamic light scattering analyses were performed equally by two analysts over a period of two days using five dilutions and twelve replicates for each dilution. Linearity evaluation using the sixty sample analysis yielded a regression coefficient R(2) = 0.959. The accuracy analysis for various dilutions indicated a recovery of 100 ± 6%. Precision analyses indicated low variance coefficients for the impact of analysts, days, and within sample error. The variation by analysts was apparent only in the most diluted sample (intermediate precision ~12%), where the photon count rate was close to the instrument detection limit. The variation for different days was apparent in the two most concentrated samples, which indicated that wastewater samples must be analyzed for nanoscale particle measurement within the same day of collection. Upon addition of 10 mg l(-1) of nanosilica to wastewater effluent samples, the measured photon count rates were within 5% of the estimated values. The results indicated that photon count rate data can effectively complement various techniques currently available to detect nanoscale particles in wastewaters.     

Performance of an electrochemical COD (chemical oxygen demand) sensor with an electrode-surface grinding unit

An electrochemical COD (chemical oxygen demand) sensor using an electrode-surface grinding unit was investigated. The electrolyzing (oxidizing) action of copper on an organic species was used as the basis of the COD measuring sensor. Using a simple three-electrode cell and a surface grinding unit, the organic species is activated by the catalytic action of copper and oxidized at a working electrode, poised at a positive potential. When synthetic wastewater was fed into the system, the measured Coulombic yields were found to be dependent on the COD of the synthetic wastewater. A linear correlation between the Coulombic yields and the COD of the synthetic wastewater was established (10-1000 mg L(-1)) when the electrode-surface grinding procedure was activated briefly at 8 h intervals. When various kinds of wastewater samples obtained from various sewage treatment plants were measured, linear correlations (r(2)> or = 0.92) between the measured EOD (electrochemical oxygen demand) value and COD of the samples were observed. At a practical wastewater treatment plant, the measurement system was successfully operated with high accuracy and good stability over 3 months. These experimental results show that the application of the measurement system would be a rapid and practical method for the determination of COD in water industries.     

典型行业废水特征有机污染物排放控制标准探讨

通过对典型行业废水有机污染物排放现状的调查研究，探讨我国现有污水排放标准存在的问题，即现有的标准不能有效控制废水特征有机污染物排放。依据美国环保局多介质环境模型，用不同方法计算水介质排放环境目标值，用该值作为标准限值，评价典型行业废水有机污染物监测结果。针对典型行业废水有机污染物排放特征，提出制订排放控制标准的建议。     

Determining the ventilation and aerosol deposition rates from routine indoor-air measurements

Measurement of air exchange rate provides critical information in energy and indoor-air quality studies. Continuous measurement of ventilation rates is a rather costly exercise and requires specific instrumentation. In this work, an alternative methodology is proposed and tested, where the air exchange rate is calculated by utilizing indoor and outdoor routine measurements of a common pollutant such as SO₂, whereas the uncertainties induced in the calculations are analytically determined. The application of this methodology is demonstrated, for three residential microenvironments in Athens, Greece, and the results are also compared against ventilation rates calculated from differential pressure measurements. The calculated time resolved ventilation rates were applied to the mass balance equation to estimate the particle loss rate which was found to agree with literature values at an average of 0.50 h^?1. The proposed method was further evaluated by applying a mass balance numerical model for the calculation of the indoor aerosol number concentrations, using the previously calculated ventilation rate, the outdoor measured number concentrations and the particle loss rates as input values. The model results for the indoors’ concentrations were found to be compared well with the experimentally measured values.     

Influence of different textile fibers on characterization of dyeing wastewater and final effluent

Textile industry needs to recover and reuse its wastewater as to fulfil the demand of increasingly strict regulations. The characterization of dyeing wastewater samples according to textile fiber and final textile effluent enables the application of different treatment methods. This study aims to characterize dyeing wastewater in black color of polyamide, polyester, and viscose fibers and final textile effluent. Samples were collected and characterized completely for major pollution indicator parameters. Dyeing wastewater of polyester showed higher values for some parameters, e.g., 4994.44% (49,944,400 mg L^?1 and 917 NTU) of turbidity and 4100.00% of phenol when compared to dyeing wastewater of other fibers. Other parameters such as pH, alkalinity, color, phosphorus, nitrogen, sulfides, chlorides, oil and grease, dissolved solids, and chemical and biochemical oxygen demand were also assessed. In addition to individual characterization, this study also presents a correlation of the contribution of each parameter to the final textile effluent. Although dyeing wastewater of polyamide contributes the most in terms of quantity for the final effluent, this study revealed that dyeing wastewater of polyester influenced the most on the final composition of the textile wastewater when evaluating color, turbidity, total iron, biochemical oxygen demand, chemical oxygen demand, phenol, mercury, oil and grease, and total phosphorus. The present study is focused on bringing new insights to provide future research with other strategies to improve the treatment of dyeing wastewater. In addition, some suggestions are also given for wastewater treatments according to type of textile fiber.     

Development and preparation of lead-containing paint films and diagnostic test materials

Lead in paint continues to be a threat to children's health in cities across the United States, which means there is an ongoing need for testing and analysis of paint. This ongoing analytical effort and especially development of new methods continue to drive the need for diagnostic testing materials that provide the analytical challenges of real-world paints. To this end, 31 different types of paint test materials were developed and prepared. Preparation of the materials included development of lead-containing paint films yielding an overall relative standard error for one individual test sample being less than 10%. The 31 diagnostic test materials prepared with these paint films included two lead pigments; lead concentrations from nominally 0 to 2.0 mg lead/cm(2) (0 to 5% lead by weight); overlayers of both "lead-free," oil-based and water-based paints; Al, Ba, and Mg as potential chemical interferents; red and black potential color interferents; and substrates of wood, metal, masonry, and plaster. These materials challenge each step in method development and evaluation, including paint sample collection and preparation, lead extraction, and measurement of solubilized lead. When the materials were used to test performance of a new lead-in-paint testing method based on extraction using a rotor/stator method and measurement using turbidimetry, the results agreed to within ±20% of the expected lead values for 30 out of 31 of the diagnostic test materials, thereby demonstrating their levels of quality and utility.     

基于Sentinel-3 OLCI影像的渤海FUI水色指数遥感提取及应用

水色是水体水文学特征的基本要素之一。水色测定主要是采用福莱尔比色表(Forel-Ule Scale)将自然水体按颜色从深蓝到红棕共分为21个级别,用以观测、记录海洋和内陆水体的颜色。基于2020—2021年大辽河口、黄河口西南及秦皇岛近岸海域的现场实测数据和同步Sentinel-3 OLCI影像,验证了FUI水色指数遥感提取结果的准确性,发现当现场测量时间与卫星过境时间接近时,FUI水色指数遥感提取结果与实测结果基本一致。利用2021年1—12月Sentinel-3 OLCI影像,提取了渤海月均FUI水色指数遥感产品,发现渤海FUI水色指数的主要变化区间为5~17,整体呈现辽东湾、渤海湾及莱州湾沿岸海域高,秦皇岛海域及其他离岸海域低的空间分布特征,且存在秋冬季高、春夏季低的时间变化规律。此外,FUI水色指数对诸多海洋生态环境问题具有显著的指示功能。尝试将其应用于海洋水色异常和海水水质类别观测,均取得了较好的应用效果。由此可见,FUI水色指数遥感提取将在今后的海洋生态环境监测与评价方面发挥重要作用。     

太湖湖泛现象的卫星遥感监测

2010年8月20日太湖地区Landsat ETM影像显示,太湖西部沿岸带存在湖泛黑水团现象,对该景遥感影像进行了大气校正,提取了湖泛样区、其他水体样区的ETM各波段光谱反射率数据统计特征。结果表明,湖泛样区在可见光波长的ETM波段1、2、3具有很低的反射率,水色暗黑,与人眼观察一致,而在反射红外波长的ETM波段4则有比波段3高的反射率,差异植被指数DVI>0,其原因为湖泛黑水团中,虽然大量蓝藻死亡分解,然而水中还残留有一定数量的活体蓝藻,残余叶绿素及细胞造成了虽然较弱、但仍较为稳定的反射红外波长处的光谱反射能力。提出了识别湖泛现象的遥感判据为ρ0.485<0.05 andρ0.56<0.08 andρ0.66<0.065 and(ρ0.83-ρ0.66)>0 andρ0.83<0.1。     

Examination of the operator and compensator tank role in urban wastewater treatment using activated sludge method

No doubt, operator is one of the main fundaments in wastewater treatment plants. By identifying the inadequacies, the operator could be considered as an important key in treatment plant. Several methods are used for wastewater treatment that requires spending a lot of cost. However, all investments of treatment facilities are useable when the expected efficiency of the treatment plant was obtained. Using experienced operator, this goal is more easily accessible. In this research, the wastewater of an urban community contaminated with moderated, diluted and highly concentrated pollution has been treated using surface and deep aeration treatment method. Sampling of these pilots was performed during winter 2008 to summer 2009. The results indicate that all analyzed parameters were eliminated using activated sludge and surface aeration methods. However, in activated sludge and deep aeration methods in combination with suitable function of operator, more pollutants could be eliminated. Hence, existence of operator in wastewater treatment plants is the basic principle to achieve considered efficiency. Wastewater treatment system is not intelligent itself and that is the operator who can organize even an inefficient system by its continuous presence. The converse of this fact is also real. Despite the various units and appropriate design of wastewater treatment plant, without an operator, the studied process cannot be expected highly efficient. In places frequently affected by the shock of organic and hydraulic loads, the compensator tank is important to offset the wastewater treatment process. Finally, in regard to microbial parameters, existence of disinfection unit is very useful.     

长江南通段水环境容量核定及总量控制研究

近年来南通市废水排放量逐年增大，一旦污染物排放量超过水环境容量，将影响到南通市供水水源的安全性，因此，对长江南通段进行水环境容量核定及总量控制研究十分必要。探讨了适用于长江水体的水环境容量计算方法和模型参数，对长江南通段水环境容量、污染物入江量及剩余环境容量进行了测算，并提出控制污染物入江量、合理利用水环境容量的措施建议。     

Quantitative detection of nitrate in water and wastewater by surface-enhanced Raman spectroscopy

The presence of inorganic nitrogen species in water can be unsuitable for drinking and detrimental to the environment. In this study, a surface-enhanced Raman spectroscopy (SERS) method coupled with a commercially available gold nanosubstrate (a gold-coated silicon material) was evaluated for the detection of nitrate and nitrite in water and wastewater. Applications of SERS coupled with gold nanosubstrates resulted in an enhancement of Raman signals by a factor of ～10⁴ compared to that from Raman spectroscopy. The new method was able to detect nitrate with linear ranges of 1–10,000 mg NO₃ ^?/L (R ²?=?0.978) and 1–100 mg NO₃ ^?/L (R ²?=?0.919) for water and wastewater samples, respectively. Among the common anions, phosphate appeared to be the major interfering anion affecting nitrate measurement. Nevertheless, the percentage error of nitrate measurement in wastewater by the proposed SERS method was comparable to that by ion chromatography. The nitrate detection limits in water and wastewater samples were about 0.5 mg/L. The SERS method could simultaneously detect sulfate, which may serve as a reference standard in water. These results suggested that the SERS coupled with nanosubstrates is a promising method to determine nitrate concentrations in water and wastewater.     

Evaluation of a fast wastewater odour characterisation procedure using a chemical sensor array

Sewage treatment works are one of the major sources that cause atmospheric odour pollution. The increase in the number of complaints about odour nuisance is due to the increase in environmental concerns. Unfortunately, the legislation on odour nuisance from sewage treatment works is very limited. In order to determine suitable thresholds on which to base legal standards, reliable and efficient odour measurement methods need to be defined. A chemical sensor array was developed for the purpose of measuring wastewater odour. This paper describes the development of the chemical sensor system which is specifically tuned to odours of wastewater origin and which can give an electronic measure of the wastewater odours. Odour emissions from a wastewater treatment facility were detected by using a quartz crystal microbalance (QCM) sensor array. The array consists of nine sensor elements, which were coated with different materials. In this paper, the usage of these novel instruments in the water industry was shown.     

Corrections for measurements of tritium in subterranean vapor using silica gel

Hazardous contaminants buried within vadose zones can accumulate in soil gas. The concentrations and spatial extent of these contaminants are measured to evaluate potential transport to groundwater for public risk evaluation. Tritium is an important contaminant found and monitored for in vadose zones across numerous sites within the US nuclear weapons complex, including Los Alamos National Laboratory. The extraction, collection, and laboratory analysis of tritium from subterranean soil gas presents numerous technical challenges that have not been fully studied. Particularly, the lack of moisture in the soil gas in the vadose zone makes it difficult to obtain enough sample (e.g., >5 g) to provide for the required measurement sensitivity, and often, only small amounts of moisture can be collected. Further, although silica gel has high affinity for water vapor and is prebaked prior to sampling, there is still sufficient residual moisture in the prebaked gel to dilute the relatively small amount of sampled moisture; thereby, significantly lowering the ??true?? tritium concentration in the soil gas. This paper provides an evaluation of the magnitude of the bias from dilution, provides methods to correct past measurements by applying a correction factor (CF), and evaluates the uncertainty of the CF values. For this, 10,000 Monte Carlo calculations were performed, and distribution parameters of CF values were determined and evaluated. The mean and standard deviation of the distribution of CF values were 1.53 ± 0.36, and the minimum, median, and maximum values were 1.14, 1.43, and 5.27, respectively.     

差减法和直接法对水中总有机碳测定结果比较

为了比较差减法和直接法对水中总有机碳测定结果,分别配制差减法和直接法的工作曲线,并分别通过差减法和直接法对不同水体中的总有机碳含量进行测定。比较测定结果,发现差减法和直接法对较清洁水体样品的TOC测定结果误差不大,而对废水样品的TOC测定结果误差较大。     

水质 色度测定——稀释倍数法探讨

稀释倍数法是测定污水色度的国家标准方法,通过对稀释次数、稀释方法的比较实验等对色度的测定方法进行探讨,提出几点体会,在色度的测定中有一定的实用性。     

YSI6600V2水质多参数仪现场快速法与实验室分光光度法测定湖泊藻类叶绿素的比较

通过将YSI6600V2水质多参数仪测得的叶绿素a值与实验室分光光度法叶绿素a测定值进行比较,分析了YSI6600V2多参数水质监测仪测定叶绿素a的准确性与局限性。结果表明,YSI6600V2测定值多数偏低,且相关性较差。将YSI6600V2测得的蓝藻密度样本分为2类后,相关性得到显著提升。提出了利用蓝藻密度对样本进行分类后,分别进行叶绿素a校正的方法,并说明了此种校正方法的局限性。     

皮革铬鞣废水回收利用中铬渣的铬量测定

本文研究了皮革铬鞣废水中铬的定性特征曲线。利用吸光度加合定律对大量实测数据进行统计处理。建立测定铬的实验室校准直线方程，相关系数γ＝０．９９６０．以此作为测定铬鞣废水及回收铬渣中铬量的实验室回归直线方程。并对本法的可靠性进行研究，结果令人满意。本法不仅大大简化了铬量测定的步骤．而且在提高分析效率的同时获得同等的检测结果。     

Effect Of Reagent (Dye) Addition In Wet Chemical Method Of Sulfur Dioxide Determination In Ambient Air

For measurement of sulfur dioxide (SO₂) in ambient air, the United States Environment Protection Agency (US EPA) had recommended the PRA dye-based colorimetric method as a reference technique. The method has been developed and applied in many countries for a longtime; however information regarding the sensitivity of the method with respect to sampling and analysis conditions is not available. Collaborative studies conducted in some of the South East Asian countries indicated substantial variations (of the order of 50%) in the measured concentrations against the true values. It was observed that dye used for color development plays an important role and even a slight variation in the way the dye solution is prepared can cause substantial variation in the measured SO₂ concentration. Because a major objective of air quality measurements is to relate air pollution concentration to the effects of air pollution, it is important that the method used should yield accurate levels of the pollutant, so that appropriate management plans can be devised and implemented effectively. In the present investigation, therefore, the role of dye used in SO₂ monitoring method has been highlighted. Different makes of dyes prepared in different modes were used to study the variation in the measured SO₂ concentration levels. Specifications of all the dyes were also tested. Need for use of certified reference material (CRM) for SO₂ has also been emphasized.     

分光光度法测定叶绿素a的比较

比较了《水和废水监测分析方法》(第四版)和ISO 10260:1992(E)中测定叶绿素a的典型方法,结果表明两种方法的测定结果之间既存在显著性差异,又有一定的相关性,从提取方法、提取溶剂和计算公式等方面讨论了原因,指出ISO方法提取效率更高,操作更简便。