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391.
聚磷硫酸铁的制备及在稠油污水处理中的应用 总被引:3,自引:0,他引:3
无机高分子聚合硫酸铁(PFS),用于处理稠油污水,沉降性能较差,脱色效果不好。在实验室制备了含磷酸根的聚合硫酸铁(PPFS),通过处理稠油污水,对影响产品絮凝效果的主要因素进行了研究。实验证明:PPFS代替PFS处理稠油污水,可得到良好的絮凝效果。 相似文献
392.
改性土壤对模拟含油废水中油的吸附 总被引:19,自引:1,他引:18
研究季铵盐阳离子表面活性剂四甲基铵离子 ( TMA)和十六烷基三甲基铵离子 ( HDTMA)改性的土壤 (黑土、黄棕壤、红壤 )对水中油的吸附作用 .结果表明 :改性土壤和未改性土壤均可吸附水中的油 ,但改性土壤对水中油的吸附能力明显高于未改性土壤 .改性土壤吸附油能力的顺序依次为 :1 CEC- HDTMA黑土 >1 CEC-HDTMA黄棕壤 >1 CEC- HDTMA红壤 >1 CEC-TMA黑土 >1 CEC-TMA黄棕壤 >1 CEC- TMA红壤 .未改性土壤和 HDTMA改性土壤对油的吸附通过分配来进行 ,吸附等温线可由 Henry方程表示 ,得出 logKSOM为 2.69,logKHDTMA为 3.35;TMA改性土壤对油的吸附符合 Langmuir方程 ,其对油的饱和吸附量分别为 1150 mg/kg( TMA黑土 ) ,751 mg/kg( TMA黄棕壤 ) ,172 mg/kg( TMA红壤 ) 相似文献
393.
含油污泥生物处理技术研究 总被引:14,自引:1,他引:13
含油污泥的成分非常复杂,主要是石油烃、沉积物、重金属和水的复杂混合物,对周围环境和人类健康产生危害,且处理难度大,一直是困扰油田的一大难题。目前所采用的处理方法主要有3种:物理化学处理、生物处理和综合利用。由于生物处理法具有节约能源、投资少、运行费用低等优点,成为最具应用潜力的含油污泥处理方法之一。论文介绍了含油污泥的危害及处理方法,简要分析了目前几种处理方法的特点,综述了4种生物处理技术的研究与应用现状,并探讨了含油污泥生物处理的影响因素。 相似文献
394.
Ram Kailash P. Yadav Efimia M. Papatheodorou Katerina Karamanoli Helen-Isis A. Constantinidou Despoina Vokou 《Chemoecology》2008,18(4):217-226
Summary. We studied the epiphytic bacterial communities of the summer leaves of eight perennial species naturally occurring in a Mediterranean
ecosystem. The species differ in essential-oil content (from rich in essential oil to non-producers) and composition, and
also in life form (from herbaceous species to tall shrubs). We compared the epiphytic bacterial communities on the basis of
(i) their abundance, (ii) their metabolic profile (derived by use of the BIOLOG Ecoplate system) and (iii) richness and diversity
of substrates that they use, as a measure of functional diversity. Among all species, the aromatic Melissa officinalis was the most abundantly colonized. The bacterial communities on the leaves of the aromatic Myrtus communis, Calamintha nepeta and Melissa officinalis, and also of Cistus incanus catabolized all 31 substrates offered; those on the evergreen-sclerophyllous species, Arbutus unedo and Quercus coccifera, catabolized only 14 and 17 substrates, respectively. Carbohydrates were consistently used abundantly by all communities,
whereas carboxylic acids were most variably used. On average, the group of aromatic plants scored higher regarding bacterial
abundance, and richness and diversity of substrates used by the bacterial communities on their leaves; the lowest values for
both substrate-use indices were recorded in A. unedo. Bacterial abundance or richness or diversity of substrates used did not vary with leaf oil content. Abundance was positively
correlated with both substrate-use indices. Results support claims that the antimicrobial effects of essential oils are not
exerted so much under natural conditions as reports based on biassays with pathogens usually show. Although essential oils
play a part in the microbial colonization of the phyllosphere, it is not likely that inhibition of phyllosphere bacteria is
essential oils’ primary role, at least in the Mediterranean environment. 相似文献
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397.
测定了江苏油田黄珏污水站原水中油珠粒径分布,为合理选择和设计污水处理工艺与装置提供了必要的基础数据。实验测定江苏油田黄珏污水站原水含油量为62.3 mg/L。该站的三相分离器具有较好的油水分离能力。原水中浮油(粒径≥99.4μm)占8.3%,粒径≥28.4μm的分散油占14.3%,而粒径≤28.4μm的分散油、浮化油等约占77.4%。单纯采用重力沉降法可除去原水中22.6%的含油量。同时对油珠粒径分布测定方法进行了改进。新方法减少了水样含油量的测定工作量,且设备简单、操作方便。 相似文献
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400.
Molly K. Chambers Daniel M. White Michael R. Lilly Larry D. Hinzman Kristie M. Hilton Robert C. Busey 《Journal of the American Water Resources Association》2008,44(2):316-327
Abstract: Lakes are important water resources on the North Slope of Alaska. Freshwater is required for oilfield production as well as exploration, which occurs largely on ice roads and pads. Since most North Slope lakes are shallow, the quantity and quality of the water under ice at the end of winter are important environmental management issues. Currently, water‐use permits are a function of the presence of overwintering fish populations, and their sensitivity to low oxygen concentrations. Sampling of five North Slope lakes during the winter of 2004‐2005 shed some light on the winter chemistry of four lakes that were used as water supplies and one undisturbed lake. Field analysis was conducted for oxygen, conductivity, pH, and temperature throughout the lake depth, as well as ice thickness and water depth. Water samples were retrieved from the lakes and analyzed for Na, Ca, K, Mg, Fe, dissolved‐organic carbon, and alkalinity in the laboratory. Lake properties, rather than pumping, were the best predictors of oxygen depletion, with the highest dissolved‐oxygen levels maintained in the lake with the lowest concentration of constituents. Volume weighted mean dissolved‐oxygen concentrations ranged from 4 to 94% of saturation in March. Dissolved oxygen and specific conductance data suggested that the lakes began to refresh in May. 相似文献