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91.
通过对目前已出台油气田含油污泥处理相关标准的解析,针对标准之间存在着适用范围不一致、检测项目名称及限值不一致、检测方法不统一以及计算基础不统一等,造成油气田环保工作者和管理者认识上的混乱,对含油污泥处理技术的选用和治理市场的管理带来诸多问题。为加快促进油气田含油污泥处理减量化、资源化、无害化技术的发展,建议尽快出台有针对性、普适性强、统一的油气田含油污泥污染控制标准,确保含油污泥处理既科学合理,又经济可行;同时制定针对性强的含油污泥污染物检测方法,检测方法统一、计算公式一致,保证结果真实可靠,具有可比性。 相似文献
92.
Kumar PR 《Environmental monitoring and assessment》2006,117(1-3):215-233
In this paper, an attempt has been made to highlight an experimental methodology for monitoring contaminant transport through
locally available silty soil and commercially available clay in geotechnical centrifuge models, for different compaction states.
Use of multiple depth sensors to determine depth distribution of sodium chloride in the soil column has been detailed. The
obtained results have been compared with argentometric method. To validate the centrifuge modelling, modelling of models has
been used. The test setup developed can simulate contaminant transport mechanisms through the soil mass, which is approximately
10 m deep, over a period of 600 days. R
e and P
e are found to be N times higher in the centrifuge models. These numbers are found to be several orders less than unity. This indicates that
laminar flow prevails and the dominating Cl− transport mechanism in centrifuge is diffusion. The study also highlights the fact that the geotechnical centrifuge modelling
can be used as a viable alternative to field scale experimentation. 相似文献
93.
为避免因腐蚀导致油气管道失效,针对因管道特性和腐蚀尺寸的不确定性使得管道剩余强度成为概率模型的特点,建立了腐蚀管道强度损失随机模型;借助可靠性理论,通过分析管道腐蚀进程的时变性特点,将管道系统由损伤积累和抗力衰减导致的剩余强度随机化;提出基于穿越率的腐蚀油气管道失效评定及安全寿命预测方法。研究结果表明:腐蚀速率和运行压力对管道失效概率及安全寿命影响显著,管道尺寸影响适中,而相关系数和拉伸强度影响较小;若腐蚀速率Va=0.2 mm/a,VL=10 mm/a或局部腐蚀缺陷半径达到管道壁厚的0.5倍时,建议作为重点风险段监测并检修。所建方法是对腐蚀油气管道运营监控和风险评估的有益补充。 相似文献
94.
Used engine oils contain metals, which upon entering soils may pose risks to human health or the environment. In this study, previously published concentrations of 23 metals in 213 used engine oil samples from the early 1970s to the mid-1990s are statistically evaluated. Neat (100%) used engine oils were found to contain relatively high concentrations of lead, calcium, and zinc, attributable to piston blow-by of leaded gasoline, calcium salt detergent additives, and zinc-bearing anti-corrosion/anti-oxidation additives, respectively. Wear metal concentrations were lower. The lead concentration in used engine oils in the U.S. declined between the 1970s and early 1990s, potentially providing a basis to constrain the “age” of used engine oil(s) in soils. The concentrations of 23 metals in used engine oils were compared to soil risk benchmarks in 15 representative jurisdictions in the U.S., Canada, Australia, and Europe. The maximum concentrations in neat (100%) used engine oil of eight metals – Be, Co, Fe, Mn, Ni, Se, Ag, and Ti – were lower than their collective minimum benchmarks in soils for the jurisdictions surveyed, indicating their concentrations in soils could not be reasonably expected to exceed any soil benchmarks. Nine metals (As, Ba, Cd, Cr, Cu, Pb, Sn, V and Zn), but particularly arsenic, cadmium, lead, tin, and zinc, were identified as potential contaminants of concern (PCOC) for soils from locations impacted with used engine oils, owing to their higher median concentrations (i.e., 2.5, 1.4, 1038, 5.0, and 922 mg/kg in oil, respectively) relative to most soil benchmarks. Site-specific benchmarks and metal concentrations at reasonable oil in soil concentrations require consideration when developing the suite of PCOC metal analytes for conducting site assessments of soils impacted by used engine oil. 相似文献
95.
活性半焦用于油田含油污水除油的研究 总被引:3,自引:0,他引:3
以经济廉价的半焦为原料,制备用于处理油田含油污水的吸附剂。采用高温焙烧活化、水蒸气活化、高压水热活化以及硝酸、氢氧化钾活化等方法对半焦进行活化处理,通过静态吸附实验测定除油率来评价活化效果,重点讨论了氢氧化钾活化条件对除油效果的影响。结果表明:KOH与半焦质量比为6∶1,80℃浸渍3 h,550℃焙烧1.5 h时,制备的活性半焦吸附除油效果最好,除油率可以达到75.6%;活性半焦对油的吸附符合Freund lich吸附方程。利用酸碱滴定法对样品表面酸碱官能团进行分析,发现KOH活化后半焦表面碱性亲油官能团明显增多;通过SEM对半焦的微观结构进行分析,发现KOH活化后半焦产生大量有利于吸附的孔结构。 相似文献
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100.
V.S. Yaliwal P.G. Tewari S.Y. Adaganti 《International Journal of Sustainable Engineering》2014,7(3):269-282
Renewable and alternative fuels have numerous advantages compared with fossil fuels as they are renewable and biodegradable and provide food and energy security and foreign exchange savings besides addressing environmental concerns and socio-economic issues (Yaliwal et al. 2013. International Journal of Sustainable Engineering, doi:10.1080/19397038.2013.801530. Zhu et al. 2011a, Applied Thermal Engineering 31 (14–15): 2271–2278; Zhu et al. 2011b, Fuel 90: 1743-1750; Banapurmath, Tewari, and Hosmath 2008, Renewable Energy 33: 2007-2018; Banapurmath 2009, “Performance, Combustion and Emission Characteristics of a Single Cylinder Direct Injection CI Engine Operated on Dual Fuel Mode Using Honge Oil and Producer Gas.” PhD thesis, 1–195; Banapurmath et al. 2011, Waste and Biomass Valorization 2: 1–11). In this context, the main objective of the present work is to study methods of biofuel production such as Honge oil methyl ester (HOME) using a conventional transesterification process and bioethanol from the Calliandra calothyrsus shrub using a new pretreatment method known as hydrothermal explosion. Further, experimental investigations were carried out on a single-cylinder, four-stroke, direct-injection stationary diesel engine operating in a dual-fuel mode using HOME, bioethanol and producer gas combinations to determine its performance, combustion and emission characteristics. The performance of the dual-fuel engine was analyzed at optimized engine conditions. HOME-Bioethanol (BE) blends such as HOME+ 5% bioethanol (BE5), HOME+ 10% bioethanol (BE10) and HOME+ 15% bioethanol (BE15) were prepared by adding bioethanol to HOME (on volume basis) in different proportions ranging from 5 to 15% with an increment of 5%. In this present work, the effect of different BE blends on the performance of producer gas fuelled dual fuel engine was studied. Experimental investigation on dual fuel engine using BE5-Producer gas operation resulted in up to 4–9% increased brake thermal efficiency with decreased hydrocarbon (HC), carbon monoxide (CO) and marginally increased nitric oxide (NOx) emission levels compared to HOME-Producer gas, BE10-producer gas and BE15-producer gas mode of operation. However, it was observed that, the overall performance of BE-producer gas operation was found to be lower compared to diesel-producer gas operation. 相似文献