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1.
处理含酚废水,普遍采用有机溶剂萃取法、吸附法、生物氧化法,这些方法均存在一定的缺陷。作者以江苏省神农集团合成分厂为例,从回收处理呋喃酚废水的治理人手,详细论述了采用离心器及络合萃取剂回收处理污水的工作原理、工艺流程及投资收益。试验结果:该回收处理呋喃酚污水方法运行效果好,确保处理后的废水含酚量在0.5mg/L以下,酚回收率大于95%,具有可观的经济效益、社会效益和环境效益。  相似文献   

2.
粉末活性炭-生物处理技术及工程应用   总被引:8,自引:0,他引:8  
粉末活性炭-生物处理技术是一种强化生物工艺。本文介绍了该工艺的设计方法以及作者在不同化工废水处理中的应用实例,表明该技术在处理难生物降解的工业废水中有很好的应用前景,而且经济上可行。  相似文献   

3.
厌氧生物反应器的设计,启动和运行控制方法   总被引:7,自引:0,他引:7  
厌氧生物反应器的设计,启动和运行控制受施工因素的影响。根据作者的使用体会论述了利用实验室工作数据,指导有效地启动和稳定运行厌氧生物反应器的方法,提供了便于操作的工作程序以及厌氧生物反应器设计的基本方法,作者还就常用的厌氧生物反应器的特性,运行要点提出了建议。  相似文献   

4.
作者在查明该区水文地质条件的基础上,提出了化工区水质预测的两种数学模型,一是有限单元法数值离散模型,二是统计模型,并以前者为主要方法,后者作为宏观验证成果的依据对化工区地下水污染进行预测研究。预测结果可靠。  相似文献   

5.
对厌氧消化中硫化氢毒性的控制   总被引:1,自引:0,他引:1  
在厌氧消化处理高浓度硫酸盐废水时,不但存在硫酸盐还原菌与产甲烷菌之间发生基质竞争的问题,而且硫酸盐还原菌将硫酸盐还原时产生的硫化氢对产甲烷菌产生毒性作用。作者介绍了硫化氢对产甲烷菌产生毒性作用的动力学方程,并详细分析了在厌氧消化条件下,硫化氢对产甲烷菌产生毒性作用的机理,重点阐述了用气体吹脱法、化学沉淀法和生物除硫法三种控制硫化氢毒性的方法。  相似文献   

6.
粉末活性炭-生物处理技术及工程应用   总被引:1,自引:0,他引:1  
粉末活性炭 生物处理技术是一种强化生物工艺。本文介绍了该工艺的设计方法以及作者在不同化工废水处理中的应用实例 ,表明该技术在处理难生物降解的工业废水中有很好的应用前景 ,而且经济上可行。  相似文献   

7.
紫外光消毒法是一种重要的污水深度处理方法,消毒器内部辐射强度的分布情况、微生物的停留时间及其运动轨迹对灭菌效果起着至关重要的作用。本文首次在国内系统介绍了采用计算流体动力学(CFD)手段对紫外光消毒器进行数值模拟研究的理论基础和技术路线,指出辐射强度的计算和停留时间的确定是其中的关键。以特定结构的紫外光消毒器为对象,对其内部流场进行了模拟计算,讨论了挡板位置不同所引起的消毒器内部速度场的变化情况;应用离散坐标辐射模型(DO)对紫外光辐射强度分布进行了模拟,同时加入离散粒子模型(DPM)来模拟消毒器内微生物的停留时长和运动轨迹,为最终计算微生物所受紫外光辐射剂量奠定了坚实的基础。  相似文献   

8.
论生活垃圾处理与污染防治技术   总被引:3,自引:0,他引:3  
详细分析了国内外生活垃圾污染途径和处理方法,根据中国生活垃圾的现状和特点,就国内外现有不同处理方式,提出了较为町行的生恬垃圾卫生填埋和污染防治技术。  相似文献   

9.
提高灰色预测精度的关键在于增加原始离散数据的光滑性。文章大介绍灰色模型的基础上,给出了寻找提高原始数据序列光滑度的变换的途径,并随文给出了一些新的变换,实例应用和误差分析充分展望了这一方法非常有效。  相似文献   

10.
我国有机磷农药废水的生化法处理研究进展   总被引:6,自引:1,他引:6  
农药废水的污染已受到国内外环保工作者的重视,我国也不例外。各种处理方法层出不穷,而生化法是处理方法中的重要方法,本文仅就我国生化法处理有机磷农药废水的研究进展作一概述。  相似文献   

11.
To advance the accuracy of bioremediation measurements, it is useful before specific experiments to attribute or estimate the influence of both experimental as well as field conditions on the expected magnitudes of microbial degradation rate coefficients. This paper analyzes the numerical contribution, or influence, of categories of conditions, such as bacterial adaptive state, electron acceptor type, mixing, generalized sorption conditions, and biodegradation temperature, on published phenanthrene biodegradation rates as an example of our regression approach. A fundamental microbial degradation rate equation is transformed to an additive model, then using multiple linear regression on published data, coefficients (of categorical variables) and a linear model are presented that estimate first-order biodegradation rate coefficients to within a factor of 3. Numerical estimates of how much bacterial adaptive state and presence of a sorption phase, the two most statistically significant factors, alter the phenanthrene biodegradation rate are presented. The influence of some measurement or field conditions, for example, the influence of oxygen reduction versus optimal nitrate reduction, cannot be distinguished statistically given the available data and range. The regression model is tested using conditions from newly published papers to estimate a priori the expected rate, which compares very favorably to measurements reported in the papers. Due to limited published data and range for extreme cases, the current coefficients do not apply to degradation of very aged phenanthrene nor very low concentrations of electron acceptors. As estimating tools, however, the coefficients themselves and the regression approach have very beneficial roles in design of experiments for both laboratory and field settings. Our method can be applied to other PAHs as sufficient data become available.  相似文献   

12.
Detailed knowledge of the quantity and composition of urban emissions is a prerequisite for successful application of atmospheric models to predict transport and distribution of primary and secondary air pollutants in the troposphere. We investigate the prospects and limitations of aircraft measurements in the determination of emission fluxes from urban areas. Our analysis focuses on data collected in September 1994 in and around Athens, Greece. Generally, emission fluxes from cities can be quantified with aircraft and with the minimum acceptable precision (uncertainty better than a factor of 2) only under very favorable meteorological conditions, namely in a homogeneous flow field in a well-mixed boundary layer. Better accuracy can be achieved only through ensemble averaging of repeated measurements. From our measurements in the Athens area, we deduced relative emission ratios of pollutant gases. With the support of ground-based measurements in a street canyon, the emission ratios NOx/CO, SO2/CO, and volatile organic compounds/CO (34 individual VOCs) could be determined with high precision. These results are very useful in analyzing differences between various existing emission inventories. Our data for VOCs reveal that the non-traffic emissions are of the same magnitude as the emissions originating from traffic.  相似文献   

13.
Measures of horizontal extinction were initiated at the Lowell Observatory at Flagstaff, Arizona In January of 1972, and by October of 1973 an instrumental accuracy compatible with the best observing conditions was achieved. Excellent data obtained in a horizontal direction during a seven night run are compared with long term highly standardized astronomical measures of extinction obtained at Flagstaff during the period 1955–1972. The data obtained both vertically and horizontally suggest that the extinction and scattering due to aerosols were at times as low as 10% of that caused by molecular (Rayleigh) scattering alone. The vertical extinction seems to correspond (with several months lag) to rough estimates of volcanic loading; the effect of the March 17, 1963 outburst of Mount Agung, a volcano on the island of Bali, very probably caused abnormally high extinction in late summer of that year. A generally high extinction level was observed throughout 1964-1965 with a rather slow decay to a “normal” level showing up by 1966. The very high level of transparency and abnormally blue sky found in 1961 was again observed in 1972. These data strongly suggest that man-made aerosols are not yet the major contributor to the particulate matter in the upper atmosphere.  相似文献   

14.
Dioxin analysis in food and feed can be characterized as an analytical application where very high accuracy is required at very low levels of contamination. Gas chromatography (GC) in combination with 13C-label isotope dilution (ID) high resolution mass spectrometry (HRMS) is the reference congener-specific technique characterized by pronounced selectivity, precision and trueness at parts-per-trillion (ppt) and sub-parts-per-trillion (sub-ppt) levels. The quality of the analytical data produced routinely by a laboratory should be adequate for its intended purpose, i.e., one will seek a compromise between the cost and time needed and the consequences of incorrect decisions due to erroneous results. The requirements for reproducibility are usually dependent on the analyte concentrations and have been expressed in various empirical functions. While Horwitz or modified functions are widely useful for many purposes, it would be difficult to expect these functions to cover every analytical problem. This study reports on precision characteristics achieved by the GC-ID-HRMS reference method for polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in food and feed in two interlaboratory method-performance studies among expert laboratories with long-standing experience in this field. Striking linear functions in log scale between reproducibility standard deviation and congener's level over a concentration range of 10(-8)-10(-14)g per g fresh weight are observed. The data fit very well to a Horwitz-type function of the form sR=0.153c0.904, where sR and c are dimensionless mass ratios expressed in pg g(-1) on fresh weight, regardless of the nature of the toxic congeners, food and feed matrices, or sample preparation methods. We demonstrate that the proposed function is suitable for use as a fitness-for-purpose criterion for proficiency assessment in interlaboratory comparisons on dioxins and related compounds in food.  相似文献   

15.
Monte Carlo simulations were conducted on a set of flux chamber measurements at a landfill to estimate the relationship between the number of flux chamber samples and study area size on the emission rate measurement accuracy. The spatial variability of flux was addressed in the study by utilizing an existing flux chamber measurement data set that is one of the most dense flux chamber sampling arrays published to date for a landfill. At a probability of 95%, the Monte Carlo simulations indicated that achieving an accuracy within 10% with the flux chamber method is highly unlikely. An accuracy within 20% was achieved for small areas of less than about 0.2 hectares using 220 flux chamber measurements, but achieving this level of accuracy for area emission sources, of similar or greater variability, that are larger than this is highly unlikely. An accuracy within 30% was achieved up to the Full Area of about 0.4 hectares if more than approximately 120 samples were obtained. Even for an accuracy within 50%, at least 40 flux chamber measurements were needed for the Full Area of about 0.4 hectares. Available methods of estimating the number of samples required were compared to the Monte Carlo simulation results. The Monte Carlo simulations indicate that, in general, more samples are required than determined from an existing statistical method, which is a function of the mean and standard deviation of the population. Specifying the number of samples based on a regulatory method results in very poor accuracy. A modification to the statistical method for estimating the number of samples, or for estimating an accuracy for a given probability and number of samples, is proposed.

Implications: The flux chamber method is the most widely used method of measuring fugitive emission rates from area sources. However, extrapolation of a set of individual flux chamber samples to a larger area results in area flux measurement values of unknown accuracy. Quantification of the accuracy of the extrapolation of a set of flux chamber measurements would be beneficial for understanding the confidence that can be placed on the measurement results. Guidance as to the appropriate number of flux chamber measurements to achieve a desired level of accuracy would benefit flux chamber method practitioners.  相似文献   


16.
Deficiencies with the current European reference method for the analysis using inductively couple plasma-mass spectrometry of metals in samples from stationary emissions sources are presented based on experimental data obtained from real samples. The effect of these deficiencies on the quality and accuracy of data is highlighted with biases of up to 40% being observed in real samples. Suggestions to improve the performance of the standard method are presented. In particular, the beneficial effect of using a drift correction procedure to account for the decrease in instrument sensitivity observed during an analytical measurement series is demonstrated. It is shown that this corrective procedure results in substantial improvements to the accuracy of data produced.  相似文献   

17.
环境监测现场室管理工作是环境监测中一项基础性管理和技术工作,监测现场的管理工作是否科学有序,关系到环境监测效率的高低,对环境监测数据质量的准确性、可靠性、可比性、完整性和公正性也有着十分重要影响。因此,做好环境监测现场室管理工作已成为环境监测管理工作者必须掌握的一项基础性科学技术。文中从环境监测现场室管理工作的实践经验出发,进一步进行探索研究,力求环境监测现场室管理工作高效可行。  相似文献   

18.
An assessment of the accuracy of emission measurements is fundamental to an understanding of the ability of an organization to comply with emission regulations. Without a knowledge of the measurement accuracy, the significance of observed differences cannot be assessed. In addition, the average emission level that a group of engines must achieve for compliance is a function of the accuracy of the measurement of the exhaust constituents; i.e., the less accurate the measurement, the lower the average level must be to assure that essentially all engines pass the compliance tests. The accuracy assessment specifically included: 1) test instrument precision, 2) calibration gas accuracy and 3) sample error due to the distribution of data resulting from gas concentrations that are spatially non-uniform. In addition, the accuracy assessment required the consideration of the following general topics: the propagation of errors in a calibration hierarchy, the proper choice of error units, surveys of instrument precision, the evaluation of the significance of various instrument errors, the assessment of the significance of sampling error, and the consideration of methods for demonstrating representative samples and improving instrument precision. An accuracy assessment considering those factors resulted in the following conclusions: 1) Emission instrument precision is best expressed as percent of full scale. 2) The proper units for bias errors are percent of point. 3) Calibration-to-calibration repeatability may be utilized to estimate instrument precision. 4) Instrument precision shows wide variations from day to day. 5) Correcting past data by post-test calibration adjustments will not, in general, improve emission data altered by instrument drift. 6) Sampling error due to the distribution of emission concentrations in space is the single largest source of uncertainty in gas turbine emission measurements.  相似文献   

19.
A numerical particulate matter (PM) measurement model is developed to characterize and evaluate PM sampling methods. Simulations are conducted using the model to evaluate currently widely used PM samplers, including Federal Reference Method (FRM) samplers. The simulations show that current PM samplers are very vulnerable to both changes in measurement target (i.e., natural variability of particle size distribution) and the sampler's design, manufacturing, and operating conditions, potentially resulting in significant errors in the monitoring data. The numerical model is used in conjunction with two types of commercially available PM monitoring devices to form a Comprehensive Particulate Matter Monitoring System (CPMMS). The first type of device can be any mass-based PM monitor with a well-defined sampling efficiency curve. The second type of device is one capable of measuring particle size distribution with a reasonably good relative accuracy between size categories but not necessarily accurate in measuring absolute mass concentrations. This study shows that CPMMS can produce much higher quality PM monitoring data than the current PM samplers under the same conditions. In addition, unlike past and current PM monitoring data such as total suspended particulates, coarse PM (PM10), fine PM (PM2.5), etc., the CPMMS monitoring data will survive changes in PM regulatory definition. A new concept, dosimetry-based PM metrics and standards, is proposed to define ambient PM level based on the deposition fraction of particles in the human respiratory tract. The dosimetry-based PM metrics is more meaningful because it correlates the ambient PM level with the portion that can be deposited in the respiratory tract without an arbitrary cutoff particle diameter. CPMMS makes dosimetry-based PM metrics and standards feasible.  相似文献   

20.
In the event of an accidental atmospheric release of radionuclides from a nuclear power plant, accurate real-time forecasting of the activity concentrations of radionuclides is acutely required by the decision makers for the preparation of adequate countermeasures. Yet, the accuracy of the forecasted plume is highly dependent on the source term estimation. Inverse modelling and data assimilation techniques should help in that respect. However the plume can locally be thin and could avoid a significant part of the radiological monitoring network surrounding the plant. Deploying mobile measuring stations following the accident could help to improve the source term estimation. In this paper, a method is proposed for the sequential reconstruction of the plume, by coupling a sequential data assimilation algorithm based on inverse modelling with an observation targeting strategy. The targeting design strategy consists in seeking the optimal locations of the mobile monitors at time t + 1 based on all available observations up to time t.The performance of the sequential assimilation with and without targeting of observations has been assessed in a realistic framework. It focuses on the Bugey nuclear power plant (France) and its surroundings within 50 km from the plant. The existing surveillance network is used and realistic observational errors are assumed. The targeting scheme leads to a better estimation of the source term as well as the activity concentrations in the domain. The mobile stations tend to be deployed along plume contours, where activity concentration gradients are important. It is shown that the information carried by the targeted observations is very significant, as compared to the information content of fixed observations. A simple test on the impact of model error from meteorology shows that the targeting strategy is still very useful in a more uncertain context.  相似文献   

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