煤矸石浸泡污染物溶解释放规律研究--阜新市新邱露天煤矿不同风化煤矸石在不同固液比条件下浸泡实验

论文对新邱露天矿不同风化程度的煤矸石在不同固液比条件下溶解释放污染物的规律进行了浸泡实验研究。结果表明:煤矸石溶解释放的主要污染物为总硬度(CaCO3)、硫酸盐(SO42-)、钠(Na )、总溶解性固体(TDS)、氟化物(F-)、耗氧量(OC)和总铁(Fe)等,氯化物(Cl-)、锰(Mn)、锌(Zn)等少量,其它重金属和砷等微量。pH值接近中性。煤矸石风化程度越高,溶解释放的无机盐类污染物量越多,新鲜混合煤矸石溶解释放出较高的氟化物(F-)、耗氧量(OC)和总铁(Fe);固液比对煤矸石中污染物的溶解释放有重要影响。固液比越小,浸泡液中污染物浓度越低,越有利于煤矸石中污染物的溶解释放,单位质量煤矸石溶解释放的污染物量越多,煤矸石中污染物的溶解释放规律受扩散控制;在同一固液比条件下,各污染物浓度变化与浸泡时间成对数曲线关系,即Ct=a bLogt。     

Cd, Cr, Cu, Ni and Pb in the water column and sediments of the Ob-Irtysh Rivers, Russia

Concentrations of Cd, Cr, Cu, Ni and Pb were determined in filtered water, suspended particulate matter, and bottom sediments from a 2000 km section of the Ob and Irtysh Rivers. Dissolved Cd, Cr, Cu and Ni concentrations are similar to, or higher than, results from other Russian Arctic and large world river-estuaries. Concentrations of Cd, Cr, Cu, Ni and Pb in suspended particulate matter are generally comparable to results from other Russian Arctic and large world rivers and estuaries. Comparison of trace metal ratios in crustal material and suspended particulate matter and bottom sediment suggests that the source of Cr, Cu and Ni is continental weathering. Particulate Cd and Pb are elevated relative to their crustal abundance, suggesting a source of these metals to the Ob-Irtysh in addition to continental weathering.     

高密度蓝藻厌氧分解过程与污染物释放实验研究

采用批次培养实验模拟高密度蓝藻堆积发生的厌氧分解过程,分析蓝藻的分解速率及污染物释放规律.厌氧分解实验中,设置三组蓝藻初始密度分别为2.23×1012、1.19×1013、4.47×1013cells/L,得到叶绿素a的分解速率常数分别为0.074、0.133、0.081 d-1.蓝藻厌氧分解过程中水体呈酸性,电导率呈上升趋势,最高值为949μS/cm.化学需氧量持续升高,而UV254值先升高后降低,说明水体中有机物浓度增大,并逐渐由大分子分解为小分子有机物.蓝藻厌氧分解释放出大量溶解态氮、磷,溶解态有机氮逐渐被降解为无机氮,铵态氮含量占90%以上.研究表明,高密度蓝藻堆积发生厌氧分解可释放大量有机物和溶解态营养盐至水体中,并且随着蓝藻密度升高,污染物释放强度增大.因此水华期间应及时打捞蓝藻,以避免蓝藻大量堆积死亡导致水源区水质下降并影响自来水出水质量.     

Emerging organic contaminants (EOCs) in freshwaters in Dunedin,New Zealand

Emerging organic contaminants (EOCs) in New Zealand freshwaters are not well documented for regulatory assessments. We collected water and sediment samples for measurement of 26 EOC compound concentrations at four waterways within the city of Dunedin (Otago province). Compounds measured ranged from stimulants and depressants to pain-killers and insect repellants. Sampling was conducted before and after the student ‘Orientation Week’ at the University of Otago. Most compounds were below detection limits in all samples. However, caffeine, carbamazepine, cotinine and DEET were all measured at concentrations above detection limits. In general, concentrations of EOC compounds were ～20% higher following the influx of students to the University though student effects varied by site and additional sampling is needed to better assess temporal variation in concentrations. These data indicate that some EOCs are present in New Zealand freshwater ecosystems.     

随机波浪下斯托克司漂移速度是否引起水面漂移物离散的研究

漂浮于自由水面的污染物的的迁移、扩散会受到天然随机海浪的影响。之前的研究（以Herterich和Hasselmann（1982）为代表）普遍认为,随机波浪作用下的斯托克司漂移速度会引起水面污染物的离散,这个离散甚至有可能跟风和海流引起的离散同一量级。本研究就随机波浪作用下的斯托克司漂移速度是否会引起水面漂移物的离散进行理论和试验探讨。从理论推导可知,随机波浪下的质量输移速度是个定常分量,因此它不会随时间变化而引起水面漂移物的离散。随后我们在实验室水槽中进行了漂移物在随机波浪（P-M谱）作用下的漂移过程的测量。试验结果也印证了随机波浪作用下的斯托克司漂移速度不会引起水面漂移物离散的结论。     

Is there a significant diffusive “salt-pump mechanism” for the transport of organic contaminants from the marine environment into fresh water aquifers? A discussion contribution

We analyse recent claims of an additional risk of diffusive intrusion by marine organic contamination (OC) into coastal aquifers, and discuss the activity-driven “salt-pump mechanism” which is claimed to accelerate this diffusion. The reported accelerations of transport of OC out of saltwater are far too large to be due to activity effects on simple diffusion. There probably is a small acceleration of diffusion out of saltwater, but there is no direct experimental evidence for this. Possible experimental artefacts are suggested. Larger effects on diffusion in the literature are shown to be not relevant to this problem. Diffusion of suspended OC, present in the experiments, is too slow to be significant; however, this suspended material is shown to have serious implications for the proposed interpretation of the results. Until these results are better understood, no conclusions about any possible environmental implications can be drawn from them.

Characteristics of distribution and transport of petroleum contaminants in fracture-karst water in Zibo Area, Shandong Province, China

Fracture-karst water is an important water resource for the water supply in North China. Petroleum contamination is one of the most problematic types of the groundwater pollution. The characteristics of distribution and transport of the petroleum contaminants in fracture-karst water are different from those in porous water. The flow velocity of fracture-karst water is much faster than the velocity of porous water on an average. Therefore, contaminant transport in fracture-karst water is an absolute advection-dominated problem. The plume of the petroleum contamination may extend to several kilometers from pollution sources. It was not caused by the oil pool floating on the water table but by the oil components dissolved and scattered in groundwater. The distribution of the petroleum contaminants over space are concentrated in the strong conductive zone on the plane. On the vertical section the highest concentration of the oil contaminants appeared in the strata where the contamination sources were located. The concentrations of the oil contaminants in wells changed greatly over time. Therefore, the curves of concentration versus time fluctuated greatly. The reasons are as follows. (a) Fracture-karst water has a very great velocity. (b) Local flow fields which were caused by pumping and stoppage in some wells changed frequently. (c) In fracture-karst aquifer the transport channels are complicated. (d) Residual oil in vadose zone was leached after rainfall. It is of great practical value for the control and remediation of petroleum contamination in fracture-karst aquifer to understand those characteristics.     

Chemostatic behaviour of major ions and contaminants in a semiarid spring and stream system near Los Alamos,NM, USA

Recent studies have focused on the relationship between solute concentrations and discharge in streams, demonstrating that concentrations can vary little relative to changes in discharge (chemostatic behaviour). Chemostatic behaviour is dependent on catchment characteristics (e.g., lithology, geomorphology, and vegetation) and chemical characteristics of the solute (e.g., availability, reactivity, and mobility). An investigation of 3 springs and a stream near Los Alamos, NM, reveals that springs can behave in a chemostatic fashion as stream systems tend to do. Another unique finding of this study is that the anthropogenic contaminants barium and the high explosive RDX (hexahydro‐1,3,5‐trinitro‐1,3,5‐triazine) can also behave chemostatically. The chemostatic behaviour of a contaminant has important implications for the residence time of contaminants in a system as well as having a major control on contaminant flux and mass transport. Redox (reduction–oxidation) and biogeochemically sensitive analytes (e.g., Fe, SO₄, and NO₃) display a combination of chemostatic and chemodynamic behaviour, showing the influence of temporally variable conditions on stream and spring chemistries.     

Characterization of Organic Contaminants in New York/New Jersey Harbor Sediments Using FTIR‐ATR and Synchrotron FTIR

Dredging and remediation of contaminated Harbor sediments requires characterization of organic pollutants. In this paper, we apply a combination of Fourier transform IR attenuated total reflectance (FTIR‐ATR) and synchrotron FTIR techniques to the investigation of sediments and related materials from New York/New Jersey Harbor and other locations. The FTIR techniques give information on the functional groups of the compounds found in the sediments and make possible measurements with a spatial resolution of about 0.015 mm. Comparisons of natural organic materials namely, river and groundwater humic substances, recent marine and lacustrine sediments, and ancient sedimentary kerogen show that contaminated NY/NJ Harbor sediments display a strong and distinct absorption in their IR spectra at 2850–2950 cm^?1 identified as a C? H stretching band, indicative of the presence of anthropogenic hydrocarbons. We suggest that the presence of this band could be used for rapid screening for the presence of contaminant organic compounds in sediments encountered in dredging operations and/or as an indicator for the efficacy of sediment decontamination technologies used for treatment of dredged material.     

Application of generalized contaminant retardation factor to a multi‐phase system

In this study, a generalized contaminant retardation factor applicable to a multiphase system where various types of colloids exist simultaneously with contaminants is derived and incorporated into an equilibrium model which is successfully applied to experimental data for which phenanthrene was used as hydrophobic organic contaminants and dissolved organic matter (DOM) or bacteria as mobile carriers. Based on the parameter values for the experimental data regarding the association of phenanthrene with solid matrix, DOM and various bacterial isolates, numerical experiments are performed to examine the transport behaviour of hydrophobic organic contaminants in various types of the multiphase system. Numerical experiments demonstrate that the extent of contaminant transport enhancement depends on the adsorption affinity of the colloid, its concentration and its mobility, and that the importance of a third phase to contaminant transport needs to be evaluated carefully with respect to the relevance of experimental conditions applied to realistic environmental conditions. Copyright © 2003 John Wiley & Sons, Ltd.