排序方式： 共有32条查询结果，搜索用时 46 毫秒
1.
BTEX异常对海域油气藏指示作用的研究 总被引：2，自引：0，他引：2
常规的油气化探方法一般是应用烷烃类作为油气勘探的基本指标,但是烷烃类易受人类活动和生物活动的干扰,使常规的化探技术在油气勘探中一直受到限制。人们开始考虑采用直接的生物标记化合物来预测油气藏,如芳烃系列中的苯系化合物苯(benzene)、甲苯(toluene)、乙苯(ethylbenzene)、二甲苯(xylem),简称BTEX。国内外研究表明,BTEX基本不受人类活动和生物活动的干扰,对油气藏具有良好的指示作用。依据南海某区的实测资料,采用自主研发的油气化探可视化评价软件进行数据处理,剥离背景异常,圈出有效的BTEX异常,并与靶区地层剖面进行了对比,结果证实了BTEX对海域油气藏具有良好的指示作用。 相似文献
2.
It is a conventional method for petroleum prospecting to generally use paraffin hydrocarbon as basic indexes of oil and gas. This conventional geochemical technology, however, shows some limits in the prospecting as paraffin is vulnerable to influences from human and biologic activities. Consequently, BTEX (short for benzene, toluene, ethyl benzene and xylem, which are direct biomarkers) among aromatic hydrocarbon series has been taken into account for the oil and gas prediction. Domestic and foreign study results demonstrate that BTEX is hardly disturbed and can well indicate oil and gas reservoirs. Based on measured data from a South China Sea area, the present authors have used self-developed visual assessment software for petroleum prospecting has been used to process data, strip background anomalies, and outline significant BTEX anomalies. By comparison with stratigraphic profiles of the target area, it is confirmed that BTEX is a good indication of marine oil and gas during the petroleum prospecting. 相似文献
3.
Two biodegradation models are developed torepresent natural attenuation of fuel－hydrocarbon contaminants as observed in a comprehensive natural-gradient tracer test in a heterogeneous aquifer on the Columbus Air Force Basein Mississippi,USA．The first, a first-order mass loss model,describes the irreversible losses of BTEX and its individual components, i．e．,benzene（B）,toluene（T）,ethyl benzene（E）,and xylene（X）．The second, a reactive pathway model,describe ssequential degradation pathways for BTEX utilizing multiple electron acceptors,including oxygen,nitrate,iron and sulfate,and via methanogenesis．The heterogeneous aquifer is represented by multiple hydraulic conductivity（ K） zones delineated on the basis of numerous flowmeter K measurements．A direct propagation artificial neural network（DPN）is used as an inverse modeling tool to estimate the biodegradation rate constants associated with each of the K zones．In both the mass loss model and the reactive pathway model,the biodegradation rate constants show an increasing trend with the hydraulic conductivity．The finding of correlation between biodegradation kinetics and hydraulic conductivity distributions is of general interest and relevance to characterization and modeling of natural attenuation of hydrocarbons in other petroleum-product contaminated sites． 相似文献
4.
某石化污染场地含水层自然降解BTEX能力评估 总被引：1，自引：0，他引：1
地下水污染问题是国家关注的重要环境问题之一,监测与评估含水层自然降解污染物能力是防治地下水污染的基本手段,也是国外地下水中修复技术研究热点课题。以华北平原某石油化工类场地为案例,通过调查场地水文地质条件、土壤及地下水污染现状,监测场地地下水中苯系物(BTEX)浓度及相关化学参数变化,运用微生物水文地球化学方法和水文地质方法,估算了该场地含水层自然降解苯系物量。这一研究成果为评估我国石油类场地地下水污染的自然修复能力提供了实证和基础数据。 相似文献
5.
岩溶含水系统遭受石油烃污染的环境问题十分普遍。相对于多孔含水介质,石油烃BTEX在石灰岩含水介质中的生
物可降解性还不确定。为此,本研究开展了BTEX在石灰石和岩溶地下水介质中的静态微元体实验。经过77天的实验检测
分析,结果表明：（1） BTEX化合物在可利用电子受体溶解氧或硝酸盐存在条件下具有生物可降解性;（2） 向系统中补充
电子受体硝酸盐,具有促进生物降解的作用,其对BTEX的去除率可高达94%;（3） 未发现补充硫酸盐能够促进BTEX生物
可降解性;（4） 甲苯和二甲苯容易被生物降解,但苯的去除具有一定的难度。 相似文献
6.
7.
近年来,应用于修复石油烃污染地下水的监测自然衰减技术得到了广泛深入研究,同时质量通量方法已逐渐成为评
估地下水燃油污染场地自然衰减监测修复效能的重要手段。通过在室内砂槽中添加乙醇汽油组分,监测其自然衰减,利用
质量通量方法,得出了BTEX和乙醇的质量减少率、自然衰减速率常数K;结合非反应示踪剂溴离子,评价了BTEX和乙醇
自然衰减因素中吸附和微生物的联合降解效应。结果表明,自然衰减是地下水中燃油组分修复的重要机制,质量通量方法
是评估自然衰减的有效方法之一。BTEX和乙醇在自然衰减过程中被去除的比例分别为78.88%和98.71%,其中约98%的
BTEX 因吸附和生物降解联合作用被去除,接近100%的乙醇因内在生物降解作用被去除;BTEX 的自然衰减速率为
0.077d-1~0.167d-1,乙醇为0.353d-1,自然条件下乙醇比BTEX更容易衰减。 相似文献
8.
Monitored natural attenuation can be a viable option for remediation of groundwater contamination by BTEX compounds. Under
the field conditions, the rate of contaminant mass attenuation through natural processes, such as biodegradation, to a large
extent affected by the groundwater flow regime, which is primarily controlled by the aquifer heterogeneity. Numerical simulation
techniques were used to describe quantitatively the relationship between biodegradation rate of BTEX and aquifer heterogeneity.
Different levels of aquifer heterogeneity were described by random hydraulic conductivity fields (K) having different statistical
parameters, the coefficient of variation (CV) and the correlation length (h). The Turning Bands Algorithm was used to generate
such K fields. Visual MODFLOW/RT3D was used to simulate the fate and transport of dissolved BTEX plume within heterogeneous
aquifers. The multispecies reactive transport approach described BTEX degradation using multiple terminal electron-accepting
processes. First-order biodegradation rate constants were calculated from simulated BTEX plumes in heterogeneous flow fields.
The results showed that aquifer heterogeneity significantly affected biodegradation rate; it decreased with increasing CV
when h was in the range of up to 12 m, whereas it increased with increasing CV when h was greater than about 12 m. For well characterized aquifers, this finding could be of great value in assessing the effectiveness
of natural attenuation during feasibility studies at BTEX contaminated sites. 相似文献
9.
Concentrations of total lead as high as 1,600 g/L were detected in gasoline-contaminated and uncontaminated groundwater at three gasoline-release sites in South Carolina. Total lead concentrations were highest in turbid groundwater samples from gasoline-contaminated and uncontaminated wells, whereas lower turbidity groundwater samples (collected using low-flow methods) had lower total lead concentrations. Dissolved lead concentrations in all wells sampled, however, were less than 15 g total lead/L, the current United States Environmental Protection Agency (US EPA) maximum contaminant level (MCL). Because many total lead concentrations exceeded the MCL, the source of lead to the groundwater system at two of the three sites was investigated using a stable lead isotope ratio approach. Plots of the stable isotope ratios of lead (Pb) in groundwater as 207Pb/206Pb versus 208Pb/206Pb, and 208Pb/204Pb versus 206Pb/204Pb were similar to ratios characteristic of lead-based minerals in local rocks of the southeastern US, and were not similar to the stable lead isotopes ratios characteristic of distant lead ore deposits such as Broken Hill, Australia, used to produce tetraethyl lead in gasoline products prior to its phase-out and ban in the United States. Moreover, the isotopic composition of dissolved lead was equivalent to the isotopic composition of total lead in turbid samples collected from the same well, suggesting that the majority of the lead detected in the groundwater samples was associated with sediment particulates of indigenous aquifer material, rather than lead associated with spilled leaded gasoline. The results of this investigation indicate that (1) lead detected at some gasoline-release sites may be derived from the local aquifer material, rather than the gasoline release, and consequently may affect site-specific remediation goals; (2) non-low flow groundwater sampling methods, such as a disposable bailer, may result in turbid groundwater samples and high total lead concentrations, and; (3) stable lead isotopes can be used to clarify the source of lead detected above permissible levels in gasoline-contaminated groundwater systems. 相似文献
10.
Laleh Seifi Ali Torabian Hossein Kazemian Gholamreza Nabi Bidhendi Ali Akbar Azimi Shapoor Nazmara Mohammad AliMohammadi 《洁净——土壤、空气、水》2011,39(10):939-948
In this paper, a novel adsorbent developed by means of granulating of natural zeolite nanoparticles (i.e., clinoptilolite) was evaluated for possible removal of the petroleum monoaromatics (i.e., benzene, toluene, ethylbenzene, and xylene, BTEX). To do this, the natural zeolite was ground to produce nanosized particulate, then modified by two cationic surfactants and granulated. The effect of various parameters including temperature, initial pH of the solution, total dissolved solids (TDS), and concentration of a competitive substance (i.e., methyl tert‐butyl ether, MTBE) were studied and optimized using a Taguchi statistical approach. The results ascertained that initial pH of the solution was the most effective parameter. However, the low pH (acidic) was favorable for BTEX adsorption onto the developed adsorbents. In this study, the experimental parameters were optimized and the best adsorption condition by determination of effective factors was chosen. Based on the S/N ratio, the optimized conditions for BTEX removal were temperature of 40°C, initial pH of 3, TDS of 0 mg/L, and MTBE concentration of 100 µg/L. At the optimized conditions, the uptake of each BTEX compounds reached to more than 1.5 mg/g of adsorbents. 相似文献