油田酸化压裂废液中F^-在土壤中的迁移规律研究

通过土柱实验研究了大庆油田酸化压裂废液中氟离子（F^-）对土壤环境的影响,考察了酸化压裂废液中不同浓度的F^-在土壤中的迁移转化规律,以及不同酸度、不同的土壤质地对F^-在土壤中的迁移规律的影响,并探讨了相关作用机理。结果表明,油田酸化压裂废液中F^-对土壤环境产生明显的影响,随着废液中v浓度增加,F^-在黑钙土中的迁移深度增加;沿土壤深度方向发展,土层中F^-含量呈现降低趋势;随着F^-浓度的变化,F^-在黑钙土中的迁移基本符合负指数y=yo＋a·exp（-x/t）规律;而随着压裂废液中酸度的增加,土壤中粘土矿物Ca^2＋、Al^3＋等阳离子浓度增高,与水中氟形成难溶化合物,从而使得F^-在土壤环境中的迁移深度反而降低;F-在大庆地区3种典型土壤中的迁移深度符合黑钙土〉黄土〉碱土的规律;油田酸化压裂废液中F^-主要存在于在10cm深度的土壤表面层。     

固体废物处理厂地下水污染预测及控制模拟

[目的]以江苏省镇江市新区大港片区某固体废物处理厂为研究对象,对地下水污染情况进行模拟研究,为同类建设项目及企业的地下水污染预测和防治提供参考。[方法]通过系统分析该固体废物处理厂野外水位和水质观测数据以及水文地质条件等资料,利用Visual Modflow软件构建了地下水水流和溶质运移模型。[结果]对厂区污水处理站防渗破损后特征污染物CODMn和氨氮运移情况以及地表硬化污染控制措施对污染物的阻隔效果进行预测评价,数值模拟预测污染物的影响范围、超标范围和最大运移距离。预测时间20a后,污染物影响范围最大,运移距离最远,且CODMn影响范围较氨氮大,运移距离较远;地表硬化后,20a后污染羽未超出评价范围。[结论]污染物主要沿水流方向迁移,对水环境的影响随时间逐渐增大,污染物浓度随着迁移距离的增加而减小,不同污染物在地下水含水层中的溶质运移范围和迁移距离不同。地表硬化措施能有效控制污染物扩散。     

Experimental Study of Tidal Effects on Coastal Groundwater and Pollutant Migration

The problem of current urban groundwater pollution is very serious, which has influenced social development and people’s daily life. Around the land-sea interface, tide obviously changes nearshore the groundwater flow regime and makes the pollutant migration process become more complex. In the present study, the effect of tide-induced groundwater table fluctuations and on the pollutants migration in beach aquifers is investigated by constructing a two-dimensional sand trough physical experimental model. The model considered brackish-water density differences and the tide by controlling experimental medium properties and boundary conditions. The results showed that the groundwater table fluctuation cycle is the same as the tidal cycle and the fluctuation lag time increases linearly with the increase of the offshore distance. Tidal fluctuation flattens brackish-freshwater interface, widens the dispersion zone, and generates the upper saline and the freshwater belt. Time lag corresponding relationships between saline water and tidal fluctuation was observed. With the pollutant approaching the saline water area, the profile of the pollutant migration is gradually developed into a spindle shape until the strip shape, and the pollutant enters the saline water body along the curved edge of the upper part of the saline water. The transverse dispersion of pollutants is larger than the longitudinal dispersion in a tidal cycle and its outline presents a strip shape development. No mixing or exchange between the pollutants and the saline water body happened during the whole process. This study can provide scientific references for nearshore groundwater pollution prevention and control in the future.     

Occurrence of PPCPs at a Wastewater Treatment Plant and in Soil and Groundwater at a Land Application Site

Pharmaceuticals and personal care products (PPCPs) can reach soil and aquatic environments through land application of wastewater effluent and agricultural runoff. The objective of this research was to assess the fate of PPCPs at field scale. PPCPs were measured systematically in a wastewater treatment plant (WWTP), and in soil and groundwater receiving treated effluent from the WWTP. A land application site in West Texas was used as the study site; it has received treated wastewater effluent from the WWTP for more than 70 years in order to remove additional nutrients and irrigate non-edible crops. Target compounds (estrone, 17??-estradiol, estriol, 17??-ethynylestradiol, triclosan, caffeine, ibuprofen, and ciprofloxacin) in wastewater, sewage sludge, soil, and groundwater were determined using HPLC/UV with qualitative confirmatory analyses using GC/MS. Samples were collected quarterly over 12 months for wastewater and sludge samples and over 9 months for soil and groundwater samples. Results indicated that concentrations of PPCPs in wastewater influent, effluent, sludge solid phase, and sludge liquid phase were in the range of non-detected (ND)-183 ??g/L, ND-83 ??g/L, ND-19 ??g/g, and ND-50 ??g/L, respectively. Concentrations in soil and groundwater samples were in the range of ND-319 ng/g and ND-1,745 ??g/L, respectively. GC/MS confirmation data were consistent with the results of HPLC/UV analyses. Overall, data indicate that PPCPs in the wastewater effluent from the WWTP transport both vertically and horizontally in the soil, and eventually reach groundwater following land application of the effluent.     

Review of Groundwater Pollution and Protection in Karst Areas

Karst groundwater (the water in a karst aquifer) is a major water resource in many regions of some countries. Water requirements for most of the settlements in the karstic regions are supplied from karst aquifers. Karst environments are also used for the disposal of liquid and solid domestic agricultural, and industrial wastes, which result in karst groundwater pollution. Karst aquifers have specific hydraulic and hydrogeologic characteristics that render them highly vulnerable to pollution from human activities. Karst groundwater becomes polluted more easily and in shorter time periods than water in non-karstic aquifers. Thus, protection measures are required to preserve the quality and quantity of karst groundwater that specifically consider the vulnerability of the karst environment. In order to preserve karst groundwater, the geological, hydrological and hydrogeological characteristics of the karst area must be investigated and information on polluting activities and sources must be collected. Then, a comprehensive protection and control system must be developed consisting of the following six components: (1) develop and implement a groundwater monitoring system, (2) establish critical protection zones, (3) develop proper land use strategies, (4) determine the reasonable development capacity of the karst aquifer, (5) control and eliminate when necessary sources of pollution, (6) increase public awareness of the value and vulnerability of karst aquifers.     

将乐县地下水资源状况与开发保护

将乐县地下水类型为松散岩孔隙水、碎屑岩类孔隙水、碳酸盐类裂隙洞水、基岩裂隙水。大气降水是将乐县地下水的主要补给来源。其地下水资源可分为山间盆地水文地质区、岩溶水文地质区、低山丘陵水文地质区、中低山水文地质区 ,另外还有两处地下热水。根据将乐县地下水资源实际状况提出了开发保护对策。     

广东某硫酸厂含铊冶炼废渣堆放场土壤铊剖面特征及迁移行为

重点研究了广东某硫酸工业废渣堆放场周围土壤剖面中铊的污染特征及迁移影响因素。研究表明,铊污染物主要集中在土壤0~16.5cm范围,并且表现出沿垂直方向向下迅速降低的特点。土壤中铊污染物活动态的比例很高,主要以铊的铁锰氧化物结合态(TlFe/MnOx)存在,铊的可交换态(Tlexc)、铊的碳酸盐结合态(Tlcar)、TlFe/MnOx在土壤中迁移性强,而铊的有机结合态(Tlorg)和铊的残余态(Tlres)迁移性相对较弱。土壤pH值是影响铊污染物在土壤中迁移的主要因素,铁锰氧化物/氢氧化物、有机质、土壤粒度组成、CEC(阳离子交换容量)是影响铊迁移的次要因素。     

Performance and Bacterial Community Diversity of a Full-Scale Biofilter Treating Leachate Odor in a Sanitary Landfill Site

Odors, such as the malodorous and toxic hydrogen sulfide (H₂S), are released during leachate collection, storage, and treatment. A full-scale biofilter was applied to treat H₂S emitted from a leachate equalization basin in a sanitary landfill site. The inlet concentration of H₂S was 26.3?C213.0?mg?m^?3. In steady state, total removal efficiency was over 90?% in summer and over 80?% in winter. The maximum elimination capacity achieved 9.1?g?m^?3?h^?1 at a loading rate of 10.5?g?m^?3?h^?1. The biofilter was effective at reducing H₂S. Factors on the level of H₂S inlet concentration and performance of the biofilter were investigated. The H₂S inlet load and removal efficiency relied on ambient and biofilter temperature, respectively. The water containing rate and relative humidity presented seasonal variation, according to which the interval period of irrigation could be optimized. The main product of H₂S degradation was sulfate, and sulfur also could be observed from the biofilter. Spatial and temporal shifts in bacterial community composition in the biofilter were determined by polymerase chain reaction-denaturing gradient gel electrophoresis followed by DNA sequence analysis. The present study revealed a correlation between biofilter performance and bacterial community structure, especially in a real application case.     

滇东南弥勒盆地蓄水构造特征分析及找水方向

蓄水构造是富集地下水的地质构造形式,它是地下水形成、运动和蓄存的场所。在干旱地区寻找地下水主要是寻找有利的蓄水构造。通过分析弥勒盆地及其周边蓄水构造的特征,能为今后弥勒地区干旱年份寻找地下水提供水文地质依据。该文在对区域地质条件、地下水系统资料进行详尽分析并结合野外现场调查的基础上,基于蓄水构造的三要素,对滇东南弥勒盆地蓄水构造类型及其特征进行了分析,认为区内主要有汇水型蓄水构造、阻水型蓄水构造和风化带型蓄水构造三类,在干旱年份岩性分界面阻水型蓄水构造、断裂型蓄水构造和风化带型蓄水构造中的地下水具有供水意义。     

大同市地下水水质现状及保护措施

水资源是基础性的自然资源和战略性的经济资源,是人类赖以生存和发展的宝贵财富。大同市水资源贫乏,是全国110座严重缺水城市之一。随着工业的发展,大同市地下水水源地的水质受到不同程度的污染,给工农业用水特别是居民生活的饮水安全造成严重威胁。根据大同市地下水水源地水质监测情况,分析了污染物的来源,提出了地下水水源的保护措施。     

不同干燥方式下黄牛肉水分分布迁移规律研究

为探索不同干燥方式对宁夏泾源黄牛肉水分分布特性及迁移规律的影响,本试验采用低场核磁共振技术(LF-NMR)结合干燥曲线,对中红外联合电加热(MICEH)、中红外(MI)、低温真空(LTV)3种干燥方式进行对比研究.结果表明,相同加热功率下泾源黄牛肉湿基含水率由72％降至20％以下所需时间分别为330、420和450 m...     

Evaluation of Groundwater Quality Characteristics near Two Waste Sites in Ibadan and Lagos,Nigeria

Two industrial and highly populated cities namely Ibadan and Lagos, both located in Southwestern Nigeria have urban migrationproblems and resource limitations. As a result, the development of residential areas near waste sites and the indiscriminate dumping of municipal waste are common in both cities. Orita-Aperin and Oworonsoki neighborhoods in Ibadan and Lagos,respectively, both located near a waste site were studied. The two areas relied on the wells as sources of drinking water hence poor drinking water quality may have health consequences. A totalof 51 ground-water samples (30 wells in Ibadan and 21 wells in Lagos) were monitored seasonally for two years in Ibadan and a year in Lagos. Results from this study revealed that some of theground-water quality constituents determined exceeded the World Health Organization (WHO) standards for drinking water irrespective of source of pollution. Some of the ground-water samples were poor in quality in terms of pH, conductivity, totaldissolved solids, chloride, nitrate, ammonia, COD, Al, Cd, Cr, Fe, Pb, Ni and total coliforms recorded. Thus, ground-water fromsome of these private wells requires further purification to ensure its fitness for human consumption.F-test, one-way parametric analysis of variance (ANOVA), Mann-Whitney `T' test and Kruskal-Wallis H-test applied to upgradient and downgradient concentrations suggest impact ofthe waste sites on ground-water quality. The Mann-Whitney testonly suggests that the downgradient values of Fe (Ibadan: dryseason (1), sulfate (Ibadan: rainy season (2) and pH (Lagos: dry season (2) were significant at 5% level of significance. For Ibadan wells, the Kruskal-Wallis test showed that variances ofspecific conductivity, dissolved solids, and chloride for Ibadanupgradient and downgradient values were unequal. Also variances of specific conductivity and dissolved solids for upgradient anddowngradient values in Lagos were unequal at 5% level of significance. Three downgradient wells in Lagos and four downgradient wells in Ibadan had significant impact due to leachate migration into drinking wells.     

Migration of nonylphenol from plastic containers to water and a milk surrogate

Nonylphenol (NP) is used as an antioxidant and plasticizer in some plastic products. After the discovery of its endocrine-disrupting potential, concern over human exposure to this chemical has increased. Recently, a group in Germany estimated the average daily intake of NP from food (7.5 microg/day), excluding water. In the present study, NP, octylphenol (OP), and their respective ethoxylates (1-5) were measured in spring water bottled in three different types of plastic (HDPE, PET, and PVC). NP was present in water from HDPE and PVC containers, at 180 and 300 ng/L respectively, which represent 4.8% and 8% of the value calculated by the German group assuming a consumption of 2 L of water per day. OP was found in water from HDPE extracts in lower amounts, 12 ng/L, and neither the NP- nor the OP-ethoxylates were detected in any of the samples. Attempts to measure these compounds in tap water were unsuccessful, probably because reaction with residual chlorine results in the formation of chlorinated byproducts. Migration of NP from HDPE containers to a milk surrogate was also evaluated; results indicate that the amounts of NP leaching into milk might be similar to those in bottled water.     

温度耦合驱动下土壤-地下水有机污染物迁移规律与模拟研究进展

场地土壤-地下水有机污染空间分布受场地温度场、水动力场、化学场和生物场等多场控制。明晰有机污染物在土壤-地下水系统中的空间分布规律和驱动机制，定量模拟污染迁移过程，是有效开展污染控制与修复的前提。在众多的影响因素中，温度通过改变有机污染物的理化性质及多相流、化学/生物作用驱动参数，进而影响其在土水介质中的迁移及空间分布。本文综述了有机污染物理化性质（密度、黏度、溶解度）和有机污染化学/生物驱动（挥发、吸附和生物降解）关键参数与温度之间的解析关系，及考虑温度影响的土壤-地下水中有机污染传质过程模拟的研究进展，并针对目前模拟研究的不足提出了耦合温度场的土壤-地下水有机污染物迁移数学模型，为定量探究温度耦合驱动下的有机污染物迁移转化过程和规律提供启示。     

我国南方某典型有机化工污染场地土壤与地下水健康风险评估

以某典型有机化工污染场地为例,开展了多层次健康风险评估,推算了土壤与地下水的筛选值和修复目标值,确定了污染修复范围及修复量。结果表明:土壤与地下水均存在不同程度的有机污染,关注污染物氯仿、四氯化碳、苯、氯苯在0~1 m的土壤修复目标值分别为0.03、0.05、0.35、6.51 mg/kg;1~3 m的土壤修复目标值分别为0.07、0.30、0.90、13.49 mg/kg;3~5 m的土壤修复目标值分别0.14、0.46、1.69、20.45 mg/kg;5~9 m的土壤修复目标值分别为0.25、0.79、2.99、36.27 mg/kg,地下水修复目标值分别为0.32、0.51、3.43、21.80 mg/L。土壤中氯仿、四氯化碳、氯苯的超标点位随深度增加而增多,其风险或危害随之增大;地下水污染区域集中,GW6号点位4种污染物均超标,其中氯仿污染最严重,致癌风险高达1.11×10–3,非致癌危害商为9.8。     

谈喷射护坡绿化技术

喷射护坡绿化方法是近年来传入我国的新技术,具有机械化程度高、生产能力大的优点,在短短几年时间里,迅速推广应用。首先回顾了喷射护坡绿化方法的发展历程,对其进行了归纳总结,随后根据喷射混合料的状态、配方以及与其他绿化方法和材料配合情况探索了喷射护坡绿化技术的分类,同时规范了喷射护坡绿化技术专业术语。     

地表水-地下水交互下傍河土壤硝酸盐氮迁移规律试验研究

为了研究地表水与地下水不同补给关系下硝酸盐氮在傍河农田的迁移规律,选取大沽河河床沙样作为沙槽试验介质,设计地表水与地下水相互补给装置,模拟无补给、地表水补给地下水和地下水补给地表水3种方式下硝酸盐氮在土壤中的迁移,通过测定各取样点硝酸盐氮含量和到达时间,分析了其迁移规律。结果表明:纯淋洗实验中,淋洗强度与沙样颗粒越小,硝酸盐氮在表层沙中的累积越明显,硝酸盐氮的迁移也越慢。地表水与地下水相互补给试验中,补给水位上升,硝酸盐氮的积累量增加、迁移到饱水带的时间缩短;补给水力坡度为0.5时,硝酸盐氮在细沙饱水带中迁移速度约为5.3 cm/min;水力坡度变为0.7时,迁移速度约为9.4 cm/min;补给水力坡度为0.5时,硝酸盐氮在中沙饱水带的迁移速度约为12.3 cm/min。硝酸盐氮在包气带中的积累量随着沙层深度的增加而减少;淋洗强度、水力坡度及沙样颗粒越大,硝酸盐氮在包气带和饱水带中的迁移速度越快;补给水位越高,硝酸盐氮迁移至饱水带的时间越短。     

绿化植物废弃物对重金属迁移的影响

采用土柱模拟实验,比较研究了覆盖绿化植物废弃物与土壤之上和绿化植物废弃物与土壤混合处理对城市绿地土壤中重金属淋溶的影响。结果表明,Zn、Pb和Cd均在80天后淋溶完全,而Cu有所不同,在80天后又有增加的趋势,原因可能跟重金属与有机质的结合能力有关。此外,绿化植物废弃物与土壤相混合能抑制Cu、Zn、Pb和Cd向下淋溶,而绿化植物废弃物覆盖于土壤之上则有促进Cu、Zn、Pb和Cd淋溶的趋势,且不论是混合处理还是覆盖处理,20cm厚绿化植物废弃物的处理均比10cm厚绿化植物废弃物处理对Cu、Zn、Pb和Cd的促进或抑制作用大。研究还得知,Cu、Zn、Pb和Cd的迁移还与土壤pH有关,低pH土壤有利于重金属的淋溶。     

Ba2+处理对减少堆置铬渣Cr6+溶出的初步研究

通过试验，分析了用钡盐法对铬渣解毒的可行性。探讨模拟酸雨淋洗对解毒后铬渣溶出特性的影响。为铬渣安全堆置提供科学依据。     

Bioavailability of Reversibly Sorbed and Desorption-Resistant 1,3-Dichlorobenzene from a Louisiana Superfund Site Soil

Microcosm batch studies were conducted to study the biodegradation of 1,3-dichlorobenzene (1,3-DCB) from the aqueous (soil free) and soil phases. For soil phase experiments, a freshly contaminated soil and a soil containing only the desorption-resistant or irreversibly bound or non-labile fraction of the contaminant were used. These experiments were designed to simulate biodegradation at Superfund site assuming sorption/desorption equilibrium was reached. The presence of the soil reduced the rates of biodegradation significantly. Nearly 100% of the total 1,3-DCB in the aqueous phase was biodegraded by enriched bacterial cultures within 7 days compared to about 55% over a 6-week incubation period from the freshly contaminated soil. The biodegradation in the soils containing only the desorption-resistant fraction of the contaminant was considerably lower (about 30%). It is believed that for freshly contaminated soil, 1,3-DCB readily desorbed into the aqueous phase and was available for microbial consumption whereas for soils containing mostly the desorption-resistant fraction of 1,3-DCB, the contaminant availability was limited by the mass transfer into the aqueous phase. Our earlier studies concluded that about 20–30% of the sorbed contaminant is tightly bound (even larger for weathered or aged soils) and is not easily extractable. This fraction is typically present in micropores or chemically bound to soil humic matter and thus is not readily accessible for microbial utilization. The findings presented here for 1,3-DCB are in agreement with those reported for other chemicals in the literature and could have implications to the current remedy, the monitored natural attenuation at the Petro Processors Inc. Superfund site in Louisiana.