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991.
Chun Wai Lee Dennis G. Tabor Kenneth A. Cowen 《Journal of Material Cycles and Waste Management》2008,10(1):38-45
The performance of four dioxin emission monitors, including two long-term sampling devices, the Dioxin-MonitoringSystem (DMS)
and AMESA (the adsorption method for sampling dioxins and furans), and two semireal-time continuous monitors, the resonance
ionization with multimirror photon accumulation time-of-flight mass spectrometer (RIMMPA-TOFMS) and the jet resonance-enhanced
multiphoton ionization (jet-REMPI) system were tested. A package boiler burning a simulated chlorinated hazardous waste was
used for a total of nine tests. Reference samples were collected during each test and analyzed for polychlorinated dibenzodioxins
and dibenzofurans (PCDDs/Fs) using gas chromatography mass spectrometry. The PCDD/F concentrations of the reference samples
measured by EPA Method 23 ranged from 0.9 to 6.0 ng toxic equivalence (TEQ)/dry standard cubic meter. The relative accuracies
achieved by DMS, AMESA, and jet-REMPI varied from 22.6% to 78.2%, with 100% data completeness. The RIMMPA-TOFMS produced no
quantifiable results due to various difficulties associated with the instrument during the testing. The two long-term samplers
were easy to install and operate and provided a cumulative, averaged emission for the sampling period. The operations of the
two semi-real-time continuous monitors were relatively complex, but one of them provided on-site, real-time data for PCDD/F
emissions from measurement of a TEQ correlative indicator compound. This article summarizes results from the individual Environmental
Technology Verification reports for the four dioxin monitors.
This work was presented, in part, at the Fourth International Conference on Combustion, Incineration/Pyrolysis and Emission
Control (i-CIPEC) 相似文献
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饮用水源水库铁锰垂直分布规律及原因 总被引:6,自引:0,他引:6
经对水温分层型季节性缺氧水库铁、锰污染的研究表明,Fe、Mn分布随着季节变化、水库水温分层而变化,呈现明显的垂直分布规律:高浓度Fe、Mn主要出现在水温分层期水库中、下层,与库底缺氧、pH值下降、基岩溶蚀、沉积物高浓度Fe、Mn释放造成的二次污染等密切相关,从而为自来水厂实施优化分层取水和污染控制提供了依据. 相似文献
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Temporal and Spatial Trends in Nutrient and Sediment Loading to Lake Tahoe,California‐Nevada,USA 下载免费PDF全文
Robert Coats Jack Lewis Nancy Alvarez Patricia Arneson 《Journal of the American Water Resources Association》2016,52(6):1347-1365
Since 1980, the Lake Tahoe Interagency Monitoring Program (LTIMP) has provided stream‐discharge and water quality data—nitrogen (N), phosphorus (P), and suspended sediment—at more than 20 stations in Lake Tahoe Basin streams. To characterize the temporal and spatial patterns in nutrient and sediment loading to the lake, and improve the usefulness of the program and the existing database, we have (1) identified and corrected for sources of bias in the water quality database; (2) generated synthetic datasets for sediments and nutrients, and resampled to compare the accuracy and precision of different load calculation models; (3) using the best models, recalculated total annual loads over the period of record; (4) regressed total loads against total annual and annual maximum daily discharge, and tested for time trends in the residuals; (5) compared loads for different forms of N and P; and (6) tested constituent loads against land use‐land cover (LULC) variables using multiple regression. The results show (1) N and P loads are dominated by organic N and particulate P; (2) there are significant long‐term downward trends in some constituent loads of some streams; and (3) anthropogenic impervious surface is the most important LULC variable influencing water quality in basin streams. Many of our recommendations for changes in water quality monitoring and load calculation methods have been adopted by the LTIMP. 相似文献
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Over the past few years, antibiotics have been considered emerging pollutants due to their continuous input and persistence in the aquatic ecosystem even at low concentrations. They have been detected worldwide in environmental matrices, indicating their ineffective removal from water and wastewater using conventional treatment methods. To prevent this contamination, several processes to degrade/remove antibiotics have been studied. This review addresses the current state of knowledge concerning the input sources, occurrence and mainly the degradation and removal processes applied to a specific class of micropollutants, the antibiotics. In this paper, different remediation techniques were evaluated and compared, such as conventional techniques (biological processes, filtration, coagulation, flocculation and sedimentation), advanced oxidation processes (AOPs), adsorption, membrane processes and combined methods. In this study, it was found that ozonation, Fenton/photo-Fenton and semiconductor photocatalysis were the most tested methodologies. Combined processes seem to be the best solution for the treatment of effluents containing antibiotics, especially those using renewable energy and by-products materials. 相似文献
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为提高多段进水A/O生物膜工艺的脱氮效率,按照进入各缺氧池的COD量与硝态氮量的比值相同,且等于一最优比值的原则进行流量分配,按照容积负荷相等的原则设计各反应单元,对多段进水A/O生物膜工艺的流量分配和反应单元容积分配同时进行优化,并采用三段进水A/O生物膜反应器试验了等流量分配模式下运行和优化模式下运行的出水水质的差异.试验结果表明,当多段进水A/O生物膜工艺在两种模式下采用相同参数运行时,优化模式下总氮(TN)去除率明显高于等流量模式,其分别为88.8%和80.3%.优化模式与等流量分配模式对COD和总凯氏氮的去除率差别不大(均可达到97%和98%以上).采用该优化设计方法可以显著提高该工艺的TN去除效率. 相似文献