119 research outputs found

    Модернизация установки подготовки нефти на Игольско-Таловом месторождении

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    Объект исследования – водонефтяная эмульсия, технология промысловой подготовки нефти Игольско-Талового месторождения. Цель работы – модернизация установки подготовки нефти Игольско-Талового месторождения для повышения эффективности разделения нефтяной эмульсии, а также снижения себестоимости нефти за счет увеличения производительности установки и снижения расхода деэмульгатора. Для достижения этой цели предлагается в существующую схему обезвоживания и обессоливания нефти после двух параллельно работающих отстойников включить электродегидратор. Рассчитана производительность электродегидратора с учетом свойств нефти месторождения «Игол», производительность составляет 437 т/час; а также определено остаточное содержание воды на выходе из электродегидратора, которое составляет 0,6% при исходном содержании воды равном 5%. Внедрение электродегидратора позволяет получать стабильные результаты по содержанию воды в нефти на выходе, тогда как в настоящее время содержание воды в нефти после отстойников колеблется в пределах 1,5-10%.Purpose – modernization of installation of preparation of oil Galskogo field to improve the efficiency of separation of oil emulsion and reduce the cost of oil by increasing plant performance and reduce the consumption of demulsifier. To achieve this goal is proposed in the existing scheme of dehydration and desalting of crude oil after two clarifiers operating in parallel to enable electrical dehydrator. The calculated performance of a desalter based on the properties of oil fields, "Igol", the performance is 437 tons/hour; and also defined the residual water content at the outlet of the desalter, which is 0.6% at an initial water content equal to 5%. The introduction of the desalter allows to obtain stable results for water content in oil output at the present time, the water content in the oil after the sump is in the range of 1.5-10%. The payback period is 3 years and 10 months

    Imprint of past and present environmental conditions on microbiology and biogeochemistry of coastal Quaternary sediments

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    To date, North Sea tidal-flat sediments have been intensively studied down to a depth of 5 m below seafloor (mbsf). However, little is known about the biogeochemistry, microbial abundance, and activity of sulfate reducers as well as methanogens in deeper layers. In this study, two 20 m-long cores were retrieved from the tidal-flat area of Spiekeroog Island, NW Germany. The drill sites were selected with a close distance of 900 m allowing to compare two depositional settings: first, a paleo-channel filled with Holocene sediments and second, a mainly Pleistocene sedimentary succession. Analyzing these cores, we wanted to test to which degree the paleo-environmental imprint is superimposed by present processes. <br><br> In general, the numbers of bacterial 16S rRNA genes are one to two orders of magnitude higher than those of <i>Archaea</i>. The abundances of key genes for sulfate reduction and methanogenesis (<i>dsr</i>A and <i>mcr</i>A) correspond to the sulfate and methane profiles. A co-variance of these key genes at sulfate-methane interfaces and enhanced ex situ AOM rates suggest that anaerobic oxidation of methane may occur in these layers. Microbial and biogeochemical profiles are vertically stretched relative to 5 m-deep cores from shallower sediments in the same study area, but still appear compressed compared to deep sea sediments. Our interdisciplinary analysis shows that the microbial abundances and metabolic rates are elevated in the Holocene compared to Pleistocene sediments. However, this is mainly due to present environmental conditions such as pore water flow and organic matter availability. The paleo-environmental imprint is still visible but superimposed by these processes

    Summary of findings and research recommendations from the Gulf of Mexico Research Initiative

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    © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Wilson, C. A., Feldman, M. G., Carron, M. J., Dannreuther, N. M., Farrington, J. W., Halanych, K. M., Petitt, J. L., Rullkotter, J., Sandifer, P. A., Shaw, J. K., Shepherd, J. G., Westerholm, D. G., Yanoff, C. J., & Zimmermann, L. A. Summary of findings and research recommendations from the Gulf of Mexico Research Initiative. Oceanography, 34(1), (2021): 228–239, https://doi.org/10.5670/oceanog.2021.128.Following the Deepwater Horizon explosion and oil spill in 2010, the Gulf of Mexico Research Initiative (GoMRI) was established to improve society’s ability to understand, respond to, and mitigate the impacts of petroleum pollution and related stressors of the marine and coastal ecosystems. This article provides a high-level overview of the major outcomes of the scientific work undertaken by GoMRI. This i scientifically independent initiative, consisting of over 4,500 experts in academia, government, and industry, contributed to significant knowledge advances across the physical, chemical, geological, and biological oceanographic research fields, as well as in related technology, socioeconomics, human health, and oil spill response measures. For each of these fields, this paper outlines key advances and discoveries made by GoMRI-funded scientists (along with a few surprises), synthesizing their efforts in order to highlight lessons learned, future research needs, remaining gaps, and suggestions for the next generation of scientists

    Precision of the current methods to measure the alkenone proxy UK'37 and absolute alkenone abundance in sediments : results of an interlaboratory comparison study

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    Measurements of the UK'37 index and the absolute abundance of alkenones in marine sediments are increasingly used in paleoceanographic research as proxies of past sea surface temperature and haptophyte (mainly coccolith-bearing species) primary productivity, respectively. An important aspect of these studies is to be able to compare reliably data obtained by different laboratories from a wide variety of locations. Hence the intercomparability of data produced by the research community is essential. Here we report results from an anonymous interlaboratory comparison study involving 24 of the leading laboratories that carry out alkenone measurements worldwide. The majority of laboratories produce data that are intercomparable within the considered confidence limits. For the measurement of alkenone concentrations, however, there are systematic biases between laboratories, which might be related to the techniques employed to quantify the components. The maximum difference between any two laboratories for any two single measurements of UK'37 in sediments is estimated, with a probability of 95%, to be <2.18C. In addition, the overall within-laboratory precision for the UK'37 temperature estimates is estimated to be <1.68C (95% probability). Similarly, from the analyses of alkenone concentrations the interlaboratory reproducibility is estimated at 32%, and the repeatability is estimated at 24%. The former is compared to a theoretical estimate of reproducibility and found to be excessively high. Hence there is certainly scope and a demonstrable need to improve reproducibility and repeatability of UK'37 and especially alkenone quantification data across the community of scientists involved in alkenone research

    Oceanic response to Pliensbachian and Toarcian magmatic events: Implications from an organic-rich basinal succession in the NW Tethys

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    The Bächental bituminous marls (Bächentaler Bitumenmergel) belonging to the Sachrang Member of the Lower Jurassic Middle Allgäu Formation were investigated using a multidisciplinary approach to determine environmental controls on the formation of organic-rich deposits in a semi-restricted basin of the NW Tethys during the Early Jurassic. The marls are subdivided into three units on the basis of mineralogical composition, source-rock parameters, redox conditions, salinity variations, and diagenetic processes. Redox proxies (e.g., pristane/phytane ratio; aryl isoprenoids; bioturbation; ternary plot of iron, total organic carbon, and sulphur) indicate varying suboxic to euxinic conditions during deposition of the Bächental section. Redox variations were mainly controlled by sea-level fluctuations with the tectonically complex bathymetry of the Bächental basin determining watermass exchange with the Tethys Ocean. Accordingly, strongest anoxia and highest total organic carbon content (up to 13%) occur in the middle part of the profile (upper tenuicostatum and lower falciferum zones), coincident with an increase in surface-water productivity during a period of relative sea-level lowstand that induced salinity stratification in a stagnant basin setting. This level corresponds to the time interval of the lower Toarcian oceanic anoxic event (T-OAE). However, the absence of the widely observed lower Toarcian negative carbon isotope excursion in the study section questions its unrestricted use as a global chemostratigraphic marker. Stratigraphic correlation of the thermally immature Bächental bituminous marls with the Posidonia Shale of SW Germany on the basis of C27/C29 sterane ratio profiles and ammonite data suggests that deposition of organic matter-rich sediments in isolated basins in the Alpine realm commenced earlier (late Pliensbachian margaritatus Zone) than in regionally proximal epicontinental seas (early Toarcian tenuicostatum Zone). The late Pliensbachian onset of reducing conditions in the Bächental basin coincided with an influx of volcaniclastic detritus that was possibly connected to complex rifting processes of the Alpine Tethys and with a globally observed eruption-induced extinction event. The level of maximum organic matter accumulation in the Bächental basin corresponds to the main eruptive phase of the Karoo-Ferrar large igneous province (LIP), confirming its massive impact on global climate and oceanic conditions during the Early Jurassic. The Bächental marl succession is thus a record of the complex interaction of global (i.e., LIP) and local (e.g., redox and salinity variations, basin morphology) factors that caused reducing conditions and organic matter enrichment in the Bächental basin. These developments resulted in highly inhomogeneous environmental conditions in semi-restricted basins of the NW Tethyan domain during late Pliensbachian and early Toarcian time

    Evaluation of triterpenols and sterols as organic matter biomarkers in a mangrove ecosystem in Northern Brazil

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    Mangrove leaves, sediment, and excrement from the land crab Ucides cordatus (swamp ghost crab) from the coastal mangrove areas of Bragança peninsula in North Brazil were analysed to determine suitable biomarkers for mangrove-derived organic matter. Leaves of Rhizophora mangle (red mangrove), the dominant species in the area, were characterised by high amounts of b-amyrin, germanicol, taraxerol, and lupeol. Avicennia germinans (black mangrove) mainly contained betulin, lupeol, and b-sitosterol, whereas significant quantities of b-sitosterol and lupeol were typical of Laguncularia racemosa (white mangrove), the locally least abundant species. Except for betulin, the excrement of U. cordatus contained all of the above substances, but most strongly reflected the triterpenol signature of R. mangle leaves, the predominant diet of this crab. Surface sediments from various mangrove locations had relatively uniform compositions that possibly reflect tidal mixing. Sediment extracts were dominated by taraxerol and contained smaller amounts of b-amyrin, germanicol, and lupeol. Only sediments in a marsh area, dominated by Sporobolus virginicus (seashore dropseed) and Eleocharis sp. (spikerush), revealed a different biomarker distribution. Core samples of subrecent sediment (up to 4000 14C yr BP), for which previous pollen analysis indicated vegetation dominated by mangroves, had compositions similar to that of surface sediment. Taraxerol was the main component in the examined mangrove sediments and may be a marker for mangrove matter in this region, although analysis of plant material did not unequivocally support this. Germanicol is suggested to be a biomarker for organic matter from R. mangle in North Brazil. It was detected in older sediments and apparently not significantly affected by ingestion by land crabs
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