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741.
K. Abbaspour V. Matta P. Huggenberger C. A. Johnson 《Journal of contaminant hydrology》2000,40(4):196
The investigation of contaminated sites is usually a long and expensive process. It is therefore desirable to use a combination of methodologies in an integrative approach that can reduce redundant information gathering. The objective of this study was to examine the usefulness of 2 non-intrusive exploration techniques in a contaminated site investigation. Borehole positioning based on geophysical measurements was compared to positioning based on the Bayesian expert system for flow-field modeling. The goal set at the field site was the assessment of the type and load of contaminants transported from the landfill site to the adjacent aquifer and the extent of leachate plumes within the groundwater. The two methods made different demands on information gathering and were found to be complementary. The geophysical approach focused attention on the waste compartments at the site and on mixing plumes in the adjacent aquifer but could not, without prior information, provided information on the flow field. The Bayesian approach to flow-field modeling determined areas of greatest model uncertainty at the model boundaries. The model highlighted areas of greatest uncertainty that might otherwise have been overlooked and provided information on the most likely mean direction of the leachate plumes. It was concluded that both methods contribute to a site investigation and should be used before additional drilling is carried out. 相似文献
742.
743.
Effect of the water–oil ratio on brine/surfactant/alcohol/oil systems optimized for soil remediation
The optimum middle-phase microemulsion used for remediation of oily contaminated soils is often obtained by mixing a certain
amount of a surfactant/alcohol mixture with oil and adjusting the salinity concentrations at a constant water–oil ratio. Upon
introduction to the subsurface, however, the system may not be in the optimum state throughout the remediation process owing
to the change in the water–oil ratio. This research has attempted to investigate the effect of the water–oil ratio on the
phase behavior of systems containing brine, anionic surfactant, alcohols, and different oils. By systematically changing the
water–oil ratio, while keeping the others variables constant, the systems exhibited different phase behavior. The results
revealed that the effect of the water–oil ratio on system behavior was significant, and analogous to that of salinity. Increasing
the water–oil ratio led the system change from winsor I → winsor III → winsor II. The greater the water–oil ratio the lower
the salinity required to produce the middle-phase microemulsion, but the narrower the salinity range of the three-phase region.
An empirical correlation has been developed in order to predict the changes in phase behavior with the changes in water–oil
ratio. This provides a useful tool for designing optimum formulations suitable for soil remediation.
Received: October 5, 1999 / Accepted: March 27, 2000 相似文献
744.
745.
746.
解脂耶氏酵母菌处理含油废水的研究 总被引:9,自引:2,他引:7
利用解脂耶氏酵母菌在最佳降解条件下分别处理色拉油、餐饮油等油脂类废水和柴油、机油等石油类废水50 h.结果表明:该菌株能快速降解油脂,在油质量浓度≤2 000 mg/L时生化反应属于一级反应,对色拉油、餐饮油中油脂的降解率分别为93.30%和85.08%,同时菌体细胞大量生长,其生物量分别为1 652.7和1 940.0 mg/L,废水处理过程中pH稳定在3~4之间;但该菌对石油的降解率低,生成的生物量少,处理后废水pH维持在6~7之间.解脂耶氏酵母菌对油的降解与自身生物量的生成有关,该菌株降解油脂类和石油类物质的途径不同,产生的脂酶系统不同,使得废水的pH变化规律不相同. 相似文献
747.
748.
为了实现油(气)田(特别是环境敏感地区)开发的可持续发展,在原有基础上,针对水网地区油田开发环境的特点,就现在环境保护技术工作中存在的重点难点问题进行进一步的研究和探讨,完善和发展了整套污染防治工艺、处理技术及处理装备。 相似文献
749.
廊坊市环境保护局认真贯彻落实《河北省陆上石油勘探开发环境保护管理办法》,对石油企业勘探开发生产过程实施较全面的环境监督管理工作,督促石油企业积极采取措施减少和治理污染,有效地遏制了石油勘探开发生产过程中所产生的污染对生态环境造成的破坏和影响,使廊坊地区的生态环境明显转好。 相似文献
750.
新疆油气田开发对环境的影响及其对策 总被引:4,自引:0,他引:4
该文论述了新疆油气田开发对大气环境,土壤,地下水以及生态环境的不同程度的影响,重点论述了对生态环境的影响,并提出了一些对策和建议,这些对新疆乃至对全国的油气田环境保护工作都具有一定的参考和借鉴作用。 相似文献