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811.
废弃油基钻井液无害化处理技术与工艺进展   总被引:4,自引:2,他引:2  
文章分析了近几年国内外废弃油基钻井液处理技术的研究进展,重点介绍了热解吸技术、摩擦热解吸技术、超临界流体萃取技术、化学反应-强化分离+无害化处理技术、超声波与化学破乳剂相结合技术以及除油剂-闪蒸回收技术等。分别对其处理废弃油基钻井液的作用原理、主要过程、处理效率及技术优缺点进行阐述,并对各种技术的优缺点进行了比较。  相似文献   
812.
高95井硫化氢处理及防治措施研究   总被引:1,自引:0,他引:1  
文章分析总结了硫化氢对钻井的影响及在钻井中应注意的事项,并结合胜利油田高95井现场取芯钻井过程中硫化氢六次高显示的处理工艺,提出了主要防治措施,对该区块的高含硫化氢井有参考借鉴价值。  相似文献   
813.
Liu H  Zhao H  Quan X  Zhang Y  Chen S  Zhao H 《Chemosphere》2011,84(4):512-518
Hydroxylated polybrominated diphenyl ethers (HO-PBDEs) have received significant attention due to their toxicities and universal presence in the environmental matrices. However, their origins are not fully understood. We explored the feasibility of the generation of HO-PBDEs through photochemical processes from bromophenol, a commonly detected pollutant with anthropogenic source in freshwater and natural source in the marine environment. The results showed that when 2,4-dibromophenol (2,4-diBP) was irradiated in aquatic solutions under simulated sunlight, significant amounts of 2′-hydroxy-2,3′,4,5′-tetrabromodipheyl ether (2′-HO-BDE68) were rapidly formed as the dimeric product of 2,4-diBP. The formation of 2′-HO-BDE68 intensified with the increase of light intensity and with the initial concentration increase of 2,4-diBP, whereas it weakened with an increase in pH. Moreover, Fe(III) and fulvic acid played important roles in the formation of 2′-HO-BDE68. This study provides important insight into a possible source of HO-PBDEs from bromophenols in natural aquatic systems through photochemical approaches.  相似文献   
814.
In this study, an Alcaligenes sp. strain DG-5 that can effectively degrade dichlorodiphenyltrichloro-ethanes (DDTs) under aerobic conditions was isolated from DDTs-contaminated sediment. Various factors that affect the biodegradation of DDTs by DG-5 were investigated. About 88 %, 65 % and 45 % of the total DDTs were consumed within 120 h when their initial concentrations were 0.5, 5 and 15 mg L?1, respectively. However, almost no degradation was observed when their concentration was increased to 30 mg L?1, but the addition of nutrients significantly improved the degradation, and 66 % and 90 % of the total DDTs were degraded at 336 h in the presence of 5 g L?1 peptone and yeast extract, respectively. Moreover, the addition of 20 mM formate also enhanced the ability of DG-5 to transform DDTs, and its DDT transformation capacity (T(c)) value was increased by 1.8 - 2.7 fold for the pure (p,p'-DDT or o,p'-DDT only) and mixed systems (p,p'-DDT, o,p'-DDT, p,p'-DDD and p,p'-DDE). Furthermore, it was found that competitive inhibition in the biodegradation by DDT compounds occurred in the mixed system.  相似文献   
815.

Introduction  

More attention has been paid to tetracycline contamination in view of its rapid increasing concentration in the environment. Therefore, it is important to set up rapid, simple, and accurate methods for monitoring tetracycline ecotoxicity.  相似文献   
816.
A precise estimate of polarization induced by surface is crucial for polarized remote sensing dedicated to monitoring aerosol properties over urban area. The accurate knowledge of interaction between surface and aerosol polarized reflectance is essential for accurately achieving aerosol properties. In order to study surface and aerosol polarized reflectance for aerosol retrievals over urban area, a new airborne directional polarimetric camera (DPC) with high spatial resolution (4 m at 4000 m a.g.l) was developed. The surface polarized reflectance over distinct surface covers of urban area (forest, shrub, and soil) were studied using DPC measurements during a field campaign in the Pearl River Delta (PRD), China. The large variations were found in surface polarized reflectance of distinct urban covers due to surface type variability. For all surface types, the empirical BPDF model cannot describe accurately surface polarized reflectance at all possible illumination and observation geometries. From the quantitatively study of relationship between surface and aerosol polarized contribution to DPC measurements, we show that the polarized contributions of aerosol, which optical properties were defined by ground-based measurements, are much larger than the polarized contribution of surface, and found that the polarized contribution of surface covers increases with decreasing NDVI. The effect of polarization accuracy of measurements on aerosol retrieval was also investigated using DPC measurements, and found that 0.1% polarization accuracy of measurements can be neglected when AOD is retrieved using polarized measurements. Based on the information of effects of polarized reflectance differences between distinct surface covers and polarization accuracy of polarized measurements on retrieved aerosols over urban area, we found that the accuracy of aerosol retrieval over forest covers is higher than other surface types using polarized remote sensing.  相似文献   
817.
利用化学强化分离-无害化技术处理废弃油基钻井液   总被引:12,自引:2,他引:10  
废弃油基钻井液因其含有油类、重金属、有机物等污染物,属国家危险废弃物,处理难度大.通过大量室内实验研究,首次采用化学强化分离-无害化技术处理废弃油基钻井液,研制了新型清油剂和无害化处理药剂,回收了废弃油基钻井液中的油类,油回收率达90%以上.回收油的品质好,除机械杂质和灰分指标外,所测的几项指标均达到GB252-200...  相似文献   
818.
一体化A/O生物膜反应器脱氮特性研究   总被引:1,自引:0,他引:1  
采用新型的一体化A/O生物膜反应器,对生活污水进行脱氮处理实验.研究了溶解氧(DO)质量浓度对硝化和反硝化作用的影响,并对反应器的脱氮特性和降解机理进行了探讨.结果表明:DO对一体化A/O反应器脱氮影响较大,随着好氧区DO的增加,NH3-N和TN的去除率相应增加.当DO为2~4 mg/L时,发生同步硝化反硝化作用,NH...  相似文献   
819.
氧化锌(ZnO)纳米粉体是一种重要的可用来降解有机污染物的光催化剂。然而,纯的ZnO仅仅能够吸收紫外光和部分可见光,不能够充分利用太阳光。采用了一种络合凝胶法来合成掺杂Al的ZnO纳米粉体。所制备出来的纳米颗粒尺寸在20~50 nm之间,它不仅对波长范围在200~400 rm之间的紫外光有很强的吸收,而且对波长范围在4...  相似文献   
820.
通过烧杯溶胞实验,考察了ClO2处理SBR剩余污泥上清液△SCOD随处理时间的变化,以确定ClO2溶胞最佳方式;在SBR中试系统,把系统排出剩余污泥的50%经ClO2处理后回流至处理系统,运行50 d,考察处理系统的污泥减量效果及其对系统污水处理效果的影响.结果表明,ClO2具有良好的溶胞作用,在最佳投量为8 mg C...  相似文献   
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