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411.
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   
412.
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   
413.
较为全面地介绍了A/O生化池和BAF生物滤池两级生化合并的应用原理和效果,对两级生化的进出水水质进行了分析,并对系统运行中存在的问题进行了阐述。  相似文献   
414.
Although polychlorinated biphenyls have never been manufactured in Ghana, it has been used extensively as dielectric fluid in electric transformers and capacitors. However, very little is known of its health and environmental impacts by both managers of these transformers and capacitors and also the general public. This work therefore seeks to explore INAA as a possible alternative to screening transformer oils for PCBs by determining the total chlorine content. The total chlorine content of transformer oil samples from Ghana that tested positive and some randomly selected samples that tested negative from screening using CLOR-N-OIL test kits, have had their total chlorine estimated. INAA using the Research Reactor located at the Ghana Atomic Energy Commission was used to estimate the total chlorine content of the oil samples. Neutron Activation and gamma ray spectroscopy using HPGe detector coupled to MAESTRO 32 software was used to determine the total chlorine content by integrating the peak area of the spectrum into a simplified program that was developed from the activation equation. Instrumental Neutron Activation Analysis was able to validate the result obtained from the test kits screening with accuracy 7.5%.The minimum total chlorine content of the positive samples determined by NAA was 71.34 μg g−1.  相似文献   
415.
We examined the relationship between cotinine measures in follicular fluid (FF) and urine to inform our exposure assessment strategy for an ongoing epidemiological study of secondhand tobacco smoke (STS) exposure and early pregnancy loss. Among subjects undergoing in vitro fertilization (IVF), we compared cotinine levels in paired urine and FF samples from the same women and examined FF cotinine levels over time. We found a weak rank-order relationship (Spearman r < 0.2) and poor agreement for classifying nonsmoking individuals as exposed to STS (sensitivity = 0.29-0.71; specificity = 0.35-0.72) between cotinine concentrations in FF and urine. We observed fair reliability (ICC = 0.42-0.52) in FF cotinine concentrations from women undergoing multiple IVF cycles. If available, FF cotinine concentrations may be desired as a biomarker of low-level tobacco smoke exposure over urinary cotinine in studies of early reproduction. Collection of multiple FF samples for cotinine analysis may be needed to accurately represent long-term STS exposure.  相似文献   
416.
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   
417.
Quartz crystal nanobalance (QCN) technique is considered as a powerful mass sensitive sensor for monitoring of materials in the sub-nanogram level. In the current study, a method based on QCN technique developed to determine Telone in air. Various coating materials including methyl phenyl silicon, 75% phenyl (OV25) and molecularly imprinted polymer (MIP) were employed. The frequency shift of OV25-modified quartz crystal was found to be linear against organohalogen compounds [Telone (soil fumigant), Koril (Herbicide), Endosulfan (organochlorine insecticide) and Chloroform (solvent)] concentrations in the range of 2.4 to 48 mg L?1 for Telone vapor and 4.8–24 mg L?1 for three other vapors. The correlation coefficients for Telone, Koril, Endosulfan and Chloroform were 0.992, 0.996, 0.989 and 0.991, respectively. The principal component analysis was also utilized to process the frequency response data of the organic vapors. Using principal component analysis, it was found that more than 93.85% of the data variance could still be explained by use of two principal components (PC1 and PC2). Subsequently, the successful discrimination of Telone and other compounds was quite possible through the principal component analysis of the transient responses of the OV25-modified electrode. In the second method, a molecularly imprinted polymer-coated sensor for Telone was developed. Molecularly imprinted polymer coated quartz crystal (MIP-QCN) showed a selective response to Telone and gave a linear relationship between frequency shift and amount of Telone from 1 to 48 mg L?1. In this investigation, the proficiency of MIP-QCN and OV25-modified QCN sensors were compared.  相似文献   
418.
废弃油基钻井液热化学破乳-离心分离实验   总被引:5,自引:1,他引:4  
废弃油基钻井液是一种含油量较高的油包水稳定体系,具有回收利用价值。采用热化学破乳-离心分离的方法,考察了破乳剂加量、破乳温度、离心机转速、破乳时间、离心时间和破乳剂浓度对废弃油基钻井液分离的影响。通过实验确定了破乳效果最好的破乳剂为巴斯夫L62,并对热化学破乳-离心分离废弃油基钻井液的影响因素进行了优化实验研究。实验结果表明,在破乳剂加量300 mg/L、离心机转速8 000 r/min、破乳温度80℃、破乳时间3 h、离心时间25 min和破乳剂质量浓度0.25%的条件下,热化学破乳-离心法处理废弃油基钻井液的脱水率达75%、脱油率达72.73%。热化学破乳-离心分离方法回收废弃油基钻井液中的油具有潜在的应用价值。  相似文献   
419.
Rice can be a major contributor to dietary arsenic exposure because of the relatively high total arsenic concentration compared to other grains, especially for people whose main staple is rice. This study employed in vitro gastrointestinal fluid digestion to determine bioaccessible or gastrointestinal fluid extractable arsenic concentration in rice. Thirty-one rice samples, of which 60 % were grown in the United States, were purchased from food stores in New York City. Total arsenic concentrations in these samples ranged from 0.090 ± 0.004 to 0.85 ± 0.03 mg/kg with a mean value of 0.275 ± 0.161 mg/kg (n = 31). Rice samples with relatively high total arsenic (>0.20 mg/kg, n = 18) were treated by in vitro artificial gastrointestinal fluid digestion, and the extractable arsenic ranged from 53 % to 102 %. The bioaccessibility of arsenic in rice decreases in the general order of extra long grain, long grain, long grain parboiled, to brown rices.  相似文献   
420.
Salmonella and Escherichia coli are two bacteria that are important causes of human and animal disease worldwide. Chlorate is converted in the cell to chlorite, which is lethal to these bacteria. An HPLC procedure was developed for the rapid analysis of chlorate (ClO3 ?), nitrate (NO3 ?), and nitrite (NO2 ?) ions in bovine ruminal fluid samples. Standard curves for chlorite, nitrite, nitrate, and chlorate were well defined linear curves with R2 values of 0.99846, 0.99106, 0.99854, and 0.99138, respectively. Concentrations of chlorite could not be accurately determined in bovine ruminal fluid because chlorite reacts with or binds a component(s) or is reduced to chloride in bovine ruminal fluid resulting in low chlorite measurements. A standard curve ranging from 25 to 150 ppm ClO3 ? ion was used to measure chlorate fortified into ruminal fluid. The concentration of chlorate was more rapidly lowered (P < 0.01) under anaerobic compared to aerobic incubation conditions. Chlorate alone or chlorate supplemented with the reductants sodium lactate or glycerol were bactericidal in anaerobic incubations. In anaerobic culture, the addition of sodium formate to chlorate-fortified ruminal fluid appeared to decrease chlorate concentrations; however, formate also appeared to moderate the bactericidal effect of chlorate against E. coli. Addition of the reductants, glycerol or lactate, to chlorate-fortified ruminal fluid did not increase the killing of E. coli at 24 h, but may be useful when the reducing equivalents are limiting as in waste holding reservoirs or composting systems required for intense animal production.  相似文献   
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