A new intelligent electronic nose system for measuring and analysing livestock and poultry farm odours

This paper introduces a new portable intelligent electronic nose system developed especially for measuring and analysing livestock and poultry farm odours. It can be used in both laboratory and field. The sensor array of the proposed electronic nose consists of 14 gas sensors, a humidity sensor, and a temperature sensor. The gas sensors were especially selected for the main compounds from the livestock farm odours. An expert system called “Odour Expert” was developed to support researchers’ and farmers’ decision making on odour control strategies for livestock and poultry operations. “Odour Expert” utilises several advanced artificial intelligence technologies tailored to livestock and poultry farm odours. It can provide more advanced odour analysis than existing commercially available products. In addition, a rank of odour generation factors is provided, which refines the focus of odour control research. Field experiments were conducted downwind from the barns on 14 livestock and poultry farms. Experimental results show that the predicted odour strengths by the electronic nose yield higher consistency in comparison to the perceived odour intensity by human panel. The “Odour Expert” is a useful tool for assisting farmers’ odour management practises. Supported by Ontario Pork, Natural Sciences and Engineering Research Council (NSERC), and Ontario Ministry of Agriculture and Food (OMAF) of Canada.     

The influence of the methods of measuring odours nuisance on the quality of life

Quality of life in urban space has become an increasingly common problem arising from cooperation between various stakeholders, especially in the context of increasing odour nuisance. That is why it is extremely important to know and shape the expectations and perceptions of residents regarding quality of life by accepting the place of residence, especially in the context of the development of cities and urban areas.The analysis of the previous research has revealed a research gap that results from the imperfections of existing odour measurement methods and the lack of an objective measurement methodology that would allow for objectification of the subjective feelings of people to the extent of perception of unpleasant odours.The purpose of this article is to verify the hypothesis about the possibility of objectifying the assessment of odour nuisance based on the comparison of quantitative research results based on the opinions of residents and sensory tests. The specific objective is to verify residents' assessments of odour nuisance by an expert team and identify a gap in those assessments.The analysis of discrepancies gives the opportunity to identify the imperfections of various research methods and look for ways to improve them. The analysis of compliance of results, on the other hand, gives the opportunity to objectify measurements and build a methodology that may be used for the purpose of assessing odour nuisance by various stakeholders.Systematic measurement of odours in a public space may serve the basis for resolving local conflicts, creating maps of odour nuisance, assessing the attractiveness of places to live, work, spending free time and tourist value, as well as conscious actions of public authorities in shaping local policies in a specific area.     

The use of sensor arrays for environmental monitoring: interests and limitations

Continuous, in situ monitoring of air, water and land quality is fundamental to most environmental applications. Low cost and non-invasive chemical sensor arrays provide a suitable technique for in situ monitoring. Their ability and performance under realistic conditions is discussed in this paper. Published studies report promising results despite a number of limitations that are associated with both the technology itself and its application in ever changing ambient conditions. Early investigations include the analysis of single substances as well as odour and wastewater organic load monitoring. Reported applications typically highlight the sensitivity of the currently available sensors to changes in temperature, humidity and flow rate. Two types of approaches are recommended to deal with these effects: either working under fixed experimental conditions or measuring the external parameters to numerically compensate for their change. The main challenge associated with the use of non-specific sensor arrays lies in establishing a relationship between the measured multivariate signals and the standards metrics that are traditionally used for quality assessment of gas mixtures. For instance, odour monitoring requires calibration against olfactometric measurements while investigations of wastewater samples still need to be correlated with organic pollution parameters such as BOD, COD or TOC. On the other hand, results obtained in the field have demonstrated how sensor arrays can be readily used as simple alarm devices or as early warning systems based on a general air/water quality index.     

Assessment of odour problem in sewage-treated effluent in a closed loop irrigation system

Uses of wastewater drives significant economic activity, supports countless livelihoods particularly those for developing countries. While using wastewater, the challenge is to identify practical, affordable safeguards that do not threaten the health of users. In Yanbu Al-Sinaiyah, treated sewage effluent (TSE) is used for landscape purposes. In the present study, the odour problem caused by TSE in community area has been addressed. Samples were collected and analysed for total coliform, odour, trihalomethanes (THMs), total organic carbon (TOC) and other physicochemical parameters. Results show that in distribution network, residual chlorine was below the detection limit, turbidity, THMs, TOC and total coliform concentration was much higher than point source, and concentration of these parameters was further increased in problematic areas. It was also observed that areas with odourous problem were at the tail of irrigation network. This indicates that odour problem was due to less residual chlorine high turbidity, high rate of coliform and TOC. In odourous water samples, carbon disulphide and dimethyl sulphide were also identified by GC/MS, while in other areas where there was no odour, both these compounds were not detected. Odour problem was successfully resolved by improving sand filtration system to minimise turbidity the main cause of odour, increasing the residual chlorine at the treatment plant and regularly flushing the distribution network.     

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.     

铁链厂总排废水中氰化物来源解析

为追溯铁链厂生产废水总排口中检出氰化物的原因,从生产工艺、废水组成、废水处理工艺、所用物料以及分析方法等环节一一进行分析,最终发现氰化物是发黑工艺过程中物料发生化学反应而产生的,通过调整工艺路线,彻底解决了氰化物污染问题。     

绍兴市典型印染废水中重金属锑排放现状及排放源调查

分析和统计的86家印染工业企业当中,废水总排口中的总锑超标率为25.6%,质量浓度0.050 mg/L以下较低排放浓度所占比例最大,达62.8%。印染废水锑排放源主要有涤棉和涤纶化纤类布料的染色、印花工艺废水,碱减量工艺废水等,工业液碱、废酸以及硫酸铝污水处理剂等原料当中含锑浓度较高。印染废水经污水处理厂集中纳管深度处理后,锑排放浓度较低,锑去除效率最高达到88.0%,大大降低了环境地表水体锑污染的风险。     

Evaluation of Olfactory Sensing in the Water Industry

On behalf of a consortium of water companies and manufacturers, an electronic olfactory sensor was evaluated for its potential application to on-line analysis within the water industry. Early results are encouraging. The sensor has the ability to detect contaminants in raw water which cause taste and odour problems, such as 2,4,6-trichloroanisole and some hydrocarbons. It can also discriminate between three different raw water sources.     

厌氧-缺氧-好氧处理工艺的污水处理厂进出水的毒性评价

为了准确评估厌氧-缺氧-好氧（A²/O）处理工艺对废水毒性的削减效率,采用斑马鱼胚胎急性毒性实验、发光细菌急性毒性实验和小鼠L929细胞毒性实验进行测试,结合理化指标,通过毒性当量（TU）法、平均毒性（AvTx）法、毒性指数（TxPr）法、最敏感测试（MST）法和潜在生态毒性效应（PEEP）法对常州市6家污水处理厂（生活污水、综合废水、化工废水、制药废水）进水和出水的生物毒性进行了评价。结果表明,斑马鱼胚胎的毒性敏感程度最高,3种受试生物的毒性评价结果具有较好的一致性。理化达标的污水处理厂出水仍存在一定的生物毒性效应,出水毒性较大的是综合污水处理厂,排入受纳水体后可能会对周围的生态环境产生潜在的生态风险。A²/O处理工艺对各污水处理厂进水的毒性削减较好,其中对制药废水的毒性削减最高,AvTx、TxPr、MST和PEEP的毒性削减率分别为99.45%、99.64%、99.48%和69.66%。与AvTx、TxPr、MST法相比,PEEP法能够更综合地评价废水毒性。     

Bacterial biosensors for rapid and effective monitoring of biodegradation of organic pollutants in wastewater effluents

Significant amounts of toxic substances which are hazardous to animals, plants, microorganisms, and other living organisms including humans are released annually into aquatic and terrestrial environments, mostly from improper wastewater discharges. Early detection of such pollutants in wastewater effluents and proper monitoring before their final release into the environment is therefore necessary. In this study, two whole-cell bacterial biosensors were constructed by transforming competent cells of Shigella flexneri and Shigella sonnei with pLUX plasmids and evaluated for their potential to monitor wastewater samples undergoing degradation by measuring bioluminescence response using a microplate luminometer. Both bacterial biosensors were found to be extremely sensitive to the wastewater samples, with different patterns, concomitant with those of the COD removals demonstrated at the different days of the degradation. Generally higher bioluminescence values were obtained at the later days of the degradation period compared to the initial values, with up to 571.76% increase in bioluminescence value obtained at day 5 for 0.1% (v/v) effluent concentration. Also, a steady decrease in bioluminescence was observed for the bacterial biosensors with increasing time of exposure to the wastewater effluent for all the sampling days. These biosensor constructs could therefore be applicable to indicate the bioavailability of pollutants in a way that chemical analysis cannot, and for in situ monitoring of biodegradation. This has great potential to offer a risk assessment strategy in predicting the level of bioremediation required during municipal wastewater treatment before their final discharge into the aquatic milieu.     

气浮+磷酸铵镁化学沉淀法处理铝材行业氟化氢铵表面处理废水

针对铝材企业NH4HF2表面处理废水含有高浓度的NHs-N和F-等特点,采用气浮+磷酸铵镁(MAP)化学沉淀法对NH4HF2废水进行预处理,可达到目标处理效果,再引入氧化废水池进一步处理,继而达标排放.经验证,该方法是一种技术可行、经济合理的NH4 HF2废水处理方法.     

Evaluation of efficiency of aircraft liquid waste treatment and identification of daily inspection indices: a case study in Changchun, China

Evaluation of the efficiency of aircraft liquid waste treatment has previously been conducted to prevent pollution of the environment. The current study aimed to provide a set of practical methods for efficient airport sanitary supervision. Aircraft liquid waste was collected at Longjia International Airport, Changchun from multiple flights. The efficiency of liquid waste treatment as well as the water quality of the wastewater processed via a second-stage wastewater facility were examined by measuring a number of physical, chemical, and biological indices. Our results indicated that treatment solely via resolvable sanitizing liquid was not sufficient. Although the contents of first-class pollutants all met the requirements of the standard criteria, the contents of a number of second-class pollutants did not satisfy these criteria. However, after further treatment via a second-stage wastewater facility installed at the airport, all indices reached second-grade requirements of the discharge standard. We suggest that daily inspection and quarantine indices at airports should include the suspension content, biological oxygen demands after 5 days, chemical oxygen demand total organic carbon content, amino nitrogen content, total phosphorous content, and the level of fecal coliforms.     

Lognormality of trace contaminant concentrations in sewage effluents

It is important to understand the statistical distribution of monitoring data for them to be of value in determining the parameters of environmental models. No such distributional information has been available for many trace contaminants in sewage effluents. This paper applies the data of a major UK sewage works’ effluent monitoring programme to determine the validity of the common assumption that data are lognormally distributed. Effluent quality was monitored at 162 wastewater treatment works over 1 year, generating over 3,000 results for each of over 40 substances, including metals, trace organic substances and pharmaceuticals. It is demonstrated that the lognormal assumption is clearly justified for the great majority of substances in the spatial case—for annual average effluent concentrations across different treatment works. In the site-specific, temporal case—for individual determinations of concentration at a single site over an annual period—lognormality is generally supported but not demonstrated so unequivocally for all site/substance combinations. The principal source of uncertainty was lack of sufficient numbers of observations reported to adequately low reporting limits.     

Bacteriological Purification of the Finnish River Kymi

With its total drainage basin of 37 107 km2 and mean annual discharge of 307 m3 s-1, the River Kymi is one of the largest in Finland. Presently it receives treated domestic wastewaters of about 160 000 inhabitants through eight treatment plants and treated industrial effluents from four paper mills, two cardboard mills and one pulp mill. In the 1960s all the wastewaters were discharged untreated to the river. However, the construction of domestic wastewater treatment plants began in the 1970s and mechanical wastewater treatment became common in industry. By the end of the 1980s practically all the wastewaters discharged to the river were treated in activated sludge processes. The aim of this paper was to investigate the influence of wastewater purification on the bacteriological quality of the river during these three decades. The bacteriological quality of the river was evaluated on the basis of annual medians of fecal streptococci (FS) calculated for 15 sites on the basis of 4804 FS enumerations from the years 1964-1992. The results show that the bacteriological quality improved steadily as the number of treatment plants increased and wastewater treatment became more effective. In the beginning of the 1960s the annual FS medians in the central part of the river were typically 1000-1500 CFU/100 ml, whereas in the 1990s they had decreased to 30-40 CFU/100 ml (CFU = colony forming units). The results indicate that FS input to the river was mainly of domestic origin.     

Disinfection by-product formation potentials in wastewater effluents and their reductions in a wastewater treatment plant

Disinfection by-product formation potentials (DBPFPs) in wastewater effluents from eight wastewater treatment plants (WWTPs) were investigated. In addition, a WWTP with one primary effluent and two different biological treatment processes was selected for a comparative study. Formation potential tests were carried out to determine the levels of DBP precursors in wastewater. WWTPs that achieved better organic matter removal and nitrification tended to result in lower DBPFPs in effluents. For the WWTP with two processes, haloacetic acid, trihalomethane, and chloral hydrate precursors were predominant DBP precursors in the primary and secondary effluents. The percent reductions of haloacetonitrile and haloketone formation potentials averaged at 96% which was high in comparison to the reductions of other classes of DBPFPs. In addition, biological treatment changed the DBPFP speciation profile by lowering the HAAFP/THMFP ratio. The eight plant survey and the comparative analysis of the WWTP with two processes implied that besides nitrification, there may be other confounding factors impacting DBPFPs. Oxic and anoxic conditions, formation and degradation of soluble microbial products had impacts on the DBPFP reductions. This information can be used by water and wastewater professionals to better control wastewater-derived DBPs in downstream potable water supplies.     

废水中可吸附有机卤化物的来源、测定方法及去除技术的研究进展

简述了废水中可吸附有机卤化物(AOX)的定义、来源和危害,以及国内外废水中AOX排放的相关法规。详细介绍了微库仑法、中子活化法、三维荧光法等AOX测定方法,以及物理法、化学法、生物法3种AOX去除技术的研究进展。并对工业废水中AOX的检测、表征及其针对性处理提出了今后的研究方向。     

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.     

Monitoring of trace metals and pharmaceuticals as anthropogenic and socio-economic indicators of urban and industrial impact on surface waters

The research focuses on the monitoring of trace metals and pharmaceuticals as potential anthropogenic indicators of industrial and urban influences on surface water. This study includes analysis of tracers use for the indication of water pollution events and discussion of the detection method of these chemicals. The following criteria were proposed for the evaluation of indicators: specificity (physical chemical properties), variability (spatial and temporal), and practicality (capacity of the sampling and analytical techniques). The combination of grab and passive water sampling (i.e., diffusive gradient in the thin film and polar organic chemical integrated samplers) procedure was applied for the determination of dissolved and labile trace metals (Ag, Cd, Cr, Cu, Ni, Pb, and Zn) and pharmaceuticals (carbamazepine, diazepam, paracetamol, caffeine, diclofenac, and ketoprofen). Samples were analyzed using inductively coupled plasma mass spectrometry (MS; trace metals) and liquid chromatography–tandem MS electrospray ionization+/? (pharmaceuticals). Our results demonstrate the distinctive spatial and temporal patterns of trace elements distribution along an urban watercourse. Accordingly, two general groups of trace metals have been discriminated: “stable” (Cd and Cr) and “time varying” (Cu, Zn, Ni, and Pb). The relationship Cd???Cu?>?Ag?>?Cr?≥?Zn was proposed as an anthropogenic signature of the industrial and urban activities pressuring the environment from point sources (municipal wastewaters) and the group Pb–Ni was discussed as a relevant fingerprint of the economic activity (industry and transport) mainly from non-point sources (runoff, atmospheric depositions, etc.). Pharmaceuticals with contrasting hydro-chemical properties of molecules (water solubility, bioaccumulation, persistence during wastewater treatment processes) were discriminated on conservative, labile, and with combined properties in order to provide information on wastewater treatment plant efficiency, punctual events (e.g., accidents on sewage works, runoff), and uncontrolled discharges. Applying mass balance modeling, medicaments were described as relevant socio-economic indicators, which can give a picture of main social aspects of the region.     

Odour emission characteristics of 22 recreational rivers in Nanjing

The odour emission characteristics of 22 recreational rivers in Nanjing were investigated and analysed. Eight odorous compounds (ammonia (NH₃), hydrogen sulphide (H₂S), sulphur dioxide (SO₂), carbon disulphide (CS₂), nitrobenzene (C₆H₅NO₂), aniline (C₆H₅NH₂), dimethylamine (C₂H₇N), and formaldehyde (HCHO)) were measured in odour emission samples collected using a custom-made emission flux hood chamber. The results showed that all odorants were detected in all monitoring rivers. NH₃ was the main odorant, with emission rates ranging from 4.86 to 15.13 μg/min m². The total odour emission rate of the Nan River, at 1 427.07 OU/s, was the highest of the all investigated rivers. H₂S, NH₃ and nitrobenzene were three key odour emission contributors according to their contributions to the total odour emission. A correlation analysis of the pollutants showed there was a significant positive correlation between the emission rate of NH₃ and the concentration of ammonia nitrogen (NH₄ ⁺-N) and total nitrogen (TN). The H₂S and SO₂ emission rates had a significant positive correlation with sulphides (S^2?) and available sulphur (AS) in the water and sediment. The content of TN, NH₄ ⁺-N, S^2? and AS in the water and sediment affected the concentration of H₂S, SO₂ and NH₃ in the emission gases. NH₄ ⁺-N, S^2? and AS are suggested as the key odour control indexes for reducing odours emitted from these recreational rivers. The study provides useful information for effective pollution control, especially for odour emission control for the recreational rivers of the city. It also provides a demonstrate example to show how to monitor and assess a contaminated river when odour emission and its control need to be focused on.     

不同规模造纸企业主要水污染物排放特征对比研究

造纸行业是废水污染物减排重点行业。以2011—2014年全国环境统计调查数据为基础,对不同规模造纸企业废水治理运行费用和绩效进行了分析,对COD、氨氮排放强度及减排潜力进行了对比。结果表明,不同规模企业污染治理与排放特征存在差异,大中型企业产排污强度低,废水治理投入大;若造纸行业企业全部达标排放,COD排放量在2014年水平上减排21.4%~47.2%,氨氮排放量降低27.7%。