Comparison of and uncertainties in raw sewage COD measurements by laboratory techniques and field UV-visible spectrometry.

A comprehensive investigation of the uncertainty of different COD analysis methods (DIN, small tube tests (STT) and UV-visible spectrometry methods) has been carried out on potassium hydrogen phthalate standard solutions and raw sewage samples from a large wastewater treatment plant. The UV-visible method allows estimating COD equivalent concentration from the measured absorption spectra by means of site specific regression and correlation functions. CODdin and CODstt methods showed equivalent global results but specific calibration relationships are necessary when high accuracy is required. The CODstt method is suitable for immediate COD analysis in the field. Sub-sampling is the main source of uncertainty. Spectrometry is able to estimate CODeq with an uncertainty of the same order of magnitude as the uncertainty in CODdin.     

Identification of humic acid-like and fulvic acid-like natural organic matter in river water using fluorescence spectroscopy

Identifying the extent of humic acid (HA)-like and fulvic acid (FA)-like natural organic matter (NOM) present in natural water is important to assess disinfection by-product formation and fouling potential during drinking water treatment applications. However, the unique fluorescence properties related to HA-like NOM is masked by the fluorescence signals of the more abundant FA-like NOM. For this reason, it is not possible to accurately characterize HA-like and FA-like NOM components in a single water sample using direct fluorescence EEM analysis. A relatively simple approach is described here that demonstrates the feasibility of using a fluorescence excitation-emission matrix (EEM) approach for identifying HA-like and FA-like NOM fractions in water when used in combination with a series of pH adjustments and filtration steps. It is demonstrated that the fluorescence EEMS of HA-like and FA-like NOM fractions from the river water sample possessed different spectral properties. Fractionation of HA-like and FA-like NOM prior to fluorescence analysis is therefore proposed as a more reasonable approach.     

Wastewater treatment in tsunami affected areas of Thailand by constructed wetlands.

The tsunami of December 2004 destroyed infrastructure in many coastal areas in South-East Asia. In January 2005, the Danish Government gave a tsunami relief grant to Thailand to re-establish the wastewater management services in some of the areas affected by the tsunami. This paper describes the systems which have been built at three locations: (a) Baan Pru Teau: A newly-built township for tsunami victims which was constructed with the contribution of the Thai Red Cross. Conventional septic tanks were installed for the treatment of blackwater from each household and its effluent and grey water (40 m3/day) are collected and treated at a 220 m2 subsurface flow constructed wetland. (b) Koh Phi Phi Don island: A wastewater collection system for the main business and hotel area of the island, a pumping station and a pressure pipe to the treatment facility, a multi-stage constructed wetland system and a system for reuse of treated wastewater. The constructed wetland system (capacity 400 m3/day) consists of vertical flow, horizontal subsurface flow, free water surface flow and pond units. Because the treatment plant is surrounded by resorts, restaurants and shops, the constructed wetland systems are designed with terrains as scenic landscaping. (c) Patong: A 5,000 m2 constructed wetland system has been established to treat polluted water from drainage canals which collect overflow from septic tanks and grey water from residential areas. It is envisaged that these three systems will serve as prototype demonstration systems for appropriate wastewater management in Thailand and other tropical countries.     

Wastewater characteristics from Greek wineries and distilleries.

The present paper deals with the characterization of wastewater generated from Greek wineries and wine distilleries. The quantity and the quality of the wastewater of a distillery depends on the type of wine (white or red), on the processes followed for the production of wine as well as on the volume of the tanks that are used. The total production of wastewater from a winery is about 1.2 times greater than the production of wine with BOD5 1740 mg/l and 1970 mg/l for white and red wine respectively, while the corresponding prices for COD are 3112 mg/l and 3997 mg/l and for the total phenolic compounds 280 and 1440 mg/l respectively. From these results, it is expected that the biological treatment of wastewater from white wines will be more efficient than that from red wines. The characteristics from the waste (vinasses) from the distillation of wines and wine lees are also presented.     

微机自动准同期原理及优越性分析

叙述发电机投入电力系统并列运行时间期操作采用的微机自动准同期原理及实现方法，并与常规的同期装置进行对比，分析微机自动准同期的优越性。     

光催化与生化组合工艺联合处理染料废水研究

通过研究两种染料活性艳红X— 3B和阳离子艳红 5GN的光催化和生化降解特性 ,发现阳离子艳红可生化降解而难光催化降解 ,而活性艳红较易光催化降解 ,生化降解性能差。将两种染料配成模拟染料废水 ,用光催化预处理去除某些易光催化但难生化降解的成分 ,或者破坏难生化降解成分 ,使之可生化性提高 ,然后采用生化工艺处理。试验结果表明 ,采用光催化与生化组合工艺处理印染模拟废水 ,脱色率达到 94 % ,而COD去除率为 94 0 9% ,在COD去除率和脱色率上远比单独用光催化或生化处理优越。     

Catchment-scale fluorescence water quality determination.

Chemical water quality determinants and river water fluorescence were determined on the River Tyne, northeast England. Statistically significant relationships between nitrate (r = 0.87), phosphate (r = 0.80), ammonia (r = 0.70), biochemical oxygen demand (BOD) (r = 0.85) and dissolved oxygen (r = -0.65) and tryptophan-like fluorescence intensity were observed. The strongest correlations are between tryptophan-like intensity and nitrate and phosphate, which in the Tyne catchment derive predominantly from point and diffuse source sewage inputs. The correlation between BOD and the tryptophan-like fluorescence intensity suggests that this fluorescence centre is related to the bioavailable or fluorescence intensity and ammonia concentration and dissolved oxygen. The weaker correlation with ammonia is due to good ammonia treatment within the wastewater treatment plants within the catchment, and that with dissolved oxygen due to the natural aeration of the river such that this is not a good indicator of water quality. Mean annual tryptophan-like fluorescence intensity, measured by both bench and portable spectrometers, agrees well with the General Water Quality Assessment as determined by the England and Wales environmental regulators, the Environment Agency.     

Detection of fatty acid beta-oxidizing syntrophic bacteria by fluorescence in situ hybridization.

A new 16S rRNA-targeted oligonucleotide probe, specific for the cluster of fatty acid beta-oxidizing syntrophic bacteria of the family Syntrophomonadaceae was designed for fluorescence in situ hybridization. This probe was evaluated with target as well as non-target cultures. Moreover this probe was assessed with butyrate and oleate degrading enrichment cultures and methanogenic sludges from full-scale plants. The results showed that the probe revealed the presence of fatty acid beta-oxidizing syntrophic bacteria in some of the samples analyzed. However, cell quantification was possible only in enrichment cultures and in a flocculent sludge from a reactor that treats lipid-rich wastewaters, but not in methanogenic granular sludges from upflow anaerobic sludge blanket reactors.     

复合生物反应器对焦化废水中典型污染物处理特性的研究

采用厌氧缺氧好氧工艺，并在好氧段投入球形填料形成复合反应器处理焦化废水，重点对好氧复合反应器中两相污泥的污染物降解活性进行了比较。试验结果表明好氧复合反应器中附着相污泥浓度高于悬浮相污泥浓度；附着相污泥对焦化废水中苯酚、喹啉和氨氮三种代表性污染物的降解能力和抗抑制性能力均高于悬浮相污泥。     

沈阳华润三洋压缩机有限公司工业废水处理及回用工程实践

沈阳华润三洋压缩机有限公司 (简称沈阳三洋公司 )依照清洁生产原则 ,实施生产废水分路收集净化处理 ,既节约原料消耗 ,提高水循环利用率 ,又减少废水排放量 ,取得了显著的经济和环境效益     

厌氧-接触氧化-稳定塘工艺处理化工制药废水

某化工制药废水含有对生物有毒性的有机氯化物和高浓度的有机化合物 ,根据当地的地理气候等自然条件采用厌氧 接触氧化 稳定塘工艺进行处理取得了成功。介绍了该工艺设计参数和工程运行的效果     

原子荧光测定水中砷汞的方法

文章阐述了用原子荧光法同时测定水中重金属砷和汞的原理、溶液的配制、仪器的选择、使用条件及测定的结果作了分析.深入研究了不同种类的酸度对砷汞的影响以及共存离子的干扰、线性范围、检出限、精密度、准确度、回收率等.     

Wastewater reclamation systems in small communities.

The demands established in the rules and regulations by the administration in Catalonia seem to exclude small communities from wastewater reclamation and reuse, due to the comparatively high costs associated with the practice at small scale. In the framework of the DRAC project (Demonstration on Wastewater Reclamation and Reuse in Catalonia) two different pre-treatment systems, one extensive (infiltration-percolation) and another intensive (ring filter), each one followed by chlorine dioxide disinfection, were tested in order to be applied for small communities wastewater reclamation and reuse. The results of this study show that infiltration-percolation systems remove very efficiently physico-chemical contaminants and microorganisms. The ring filter system does not show a significant removal rate of contaminants, The use of infiltration-percolation as a pre-treatment for advanced chemical disinfection allows reducing the dose of disinfectant and the contact time needed to achieve a specific water quality, and diminishes disinfection byproducts (DBPs) generation. Therefore, this reclamation line is suitable for small communities due to its efficiency and low cost. However, further studies are needed in relation to the removal mechanisms of microorganisms, organic compounds in IP systems and the possible DBPs formation using chlorine dioxide.     

Wastewater dissolved organic matter: characteristics and sorptive capabilities.

An evaluation of the mobility of organic pollutants with wastewater dissolved organic matter (DOM) is essential to better understanding their fate and toxicity to the environment. In this study, DOM from two wastewater treatment plants (in Lachish and Netanya, Israel) were fractionated to hydrophobic-acid (HoA) and hydrophobic-neutral (HoN) fractions. The fractions were characterised and their sorptive capabilities for s-triazine herbicides and polycyclic aromatic hydrocarbons (PAHs) were studied. For all sorbates, binding to the HoN fractions was much higher than to HoA fractions. The high binding coefficients obtained for the studied triazines by the HoN fractions suggested that their sorption is governed by hydrophobic-like interactions rather than H-bonding. The binding coefficients of PAHs measured for the HoN fractions were within the range reported for humic acids and much higher than for the HoA fraction, suggesting that the HoN fraction plays an important role in the overall sorption of these compounds by DOM. Higher sorption coefficients were measured for the Netanya DOM sample containing a higher level of hydrophobic fractions (HoA + HoN) than the Lachish DOM, suggesting that the sorption of hydrophobic organic compounds by DOM is governed by the relative content of these structural substances.     

Wastewater treatment with anaerobic membrane bioreactor and reverse osmosis.

Domestic wastewater from a new city district in Stockholm has been treated by an anaerobic membrane bioreactor (AMBR) followed by reverse osmosis (RO). The main objectives were to study the gas production, the reduction of organic matter and nutrient recovery. The AMBR was operated at 22 degrees C (equal to the average temperature in the influent) and a hydraulic retention time of 0.6 d. The results show that the reduction of organic matter, nitrogen and phosphorus over the AMBR was approximately 92, 9 and 9%, respectively. A stable gas production was registered throughout the evaluation period. The overall removal efficiency, i.e. including the RO, was >99% for TOC, >91% for Kj-N and about 99% for P. Adding a reverse osmosis (RO) unit to the AMBR makes it possible to produce a concentrated, nutrient rich product well suited for agricultural use. The quality of the concentrate is, in terms of nutrient concentration and heavy metal content, similar to source separated human urine, i.e. nitrogen content about 3 g N/L and <2 mg Cd/kg P. However, addition of acid is required to prevent precipitation/fouling of the RO. The total electricity use for operation for the system, including the RO-unit, is estimated to be 3-6 kWh/m3.     

Wastewater treatment with activated pre-clarifier and planted soil filters.

With a series of buffer tank, activated pre-clarifier (SBR) and planted soil filters, it is possible to get a stable degradation and good effluent values in the case of unsteady inflow and changing concentrations. In the process presented here the activated pre-clarifier is working as a denitrification tank and the soil filter as a nitrification reactor. An automatic control manages the storm-water runoff, the water-recirculation returns the nitrate and provides a minimal feed. Experiences with this plant from 1999 to 2005 are given in this paper, research has been done in the project "Planted soil filters as a Biotechnological Process", founded by the German Federal Environment Foundation (DBU). A full scale pilot plant was built to treat wastewater from composting sides, with a 42 m3 SBR and a bed area of 2 x 550 m2 of the planted soil filters. Now, after six years of operation, the results are still satisfactory. Besides this pilot plant, landfill leakage and municipal wastewater have been treated in a technical scale plant with the same process in an 80 L SBR and 0.75 m2 vertical flow soil filter with good results.     

同频法计算控制站地表径流汇出特征分析

利用均匀分布的特征降水与汇出径流同频假定计算控制站地表径流的汇出特征,回避了区域水资源开发利用调查给汇出地表径流系列带来的偏差,并应用次方法计算了天津市入境特征水量,回避了上游水资源开发不同阶段不同程度对径流系列的影响以及该影响给入境水量计算带来的困难。另外,针对不同阶段不同程度的降水径流关系,利用同频法还可以计算和复核相应阶段相应程度下的区域汇出径流水平特征和水资源开发差值,为分析区域建设和规划的基础数据提供相应的计算方法。     

奥贝尔氧化沟处理炼油厂废水应注意的几个问题

就长岭炼油化工有限公司奥贝尔氧化沟设计、施工及运行过程中出现的氧化沟空池上浮、充氧设备配置失当及主轴断裂等问题及其造成的运行后果进行了讨论 ,阐述了设计、施工过程中出现的偏差对氧化沟溶解氧控制所带来的影响 ,并就溶解氧分配时应注意的事项及大型构筑物防空池上浮等问题提出了建议。     

A/O工艺稳定运行初期对城市污水污染物净化特性的研究

利用调试的A/O工艺处理城市污水,结果表明调试后的A/O工艺能很好的去除城市污水中的COD、氨氮和SS等污染物,COD、BOD和SS去除率达到80%以上.,经过A/O工艺处理后污水中COD、氨氮和SS等污染物在运行过程中绝大部分时间能达到<污水综合排放标准>(B类)(18919-2002)标准,甚至90%以上的运行时间能达到<污水综合排放标准>(A类)(18919-2002)标准.