Hasil untuk "Petroleum refining. Petroleum products"

C. Gunathilake, Ibrahim Soliman, Dhruba Panthi et al.

The transformation from combustion-based to renewable energy technologies is of paramount importance due to the rapid depletion of fossil fuels and the dramatic increase in atmospheric CO2 levels resulting from growing global energy demands. To achieve the Paris Agreement's long-term goal of carbon neutrality by 2050, the full implementation of clean and sustainable energy sources is essential. Consequently, there is an urgent demand for zero or low-carbon fuels with high energy density that can produce electricity and heat, power vehicles, and support global trade. This review presents the global motivation to reduce carbon dioxide by utilizing hydrogen technology, which is key to meeting future energy demands. It discusses the basic properties of hydrogen and its application in both prototype and large-scale efficient technologies. Hydrogen is a clean fuel and a versatile energy carrier; when used in fuel cells or combustion devices, the final product is water vapor. Hydrogen gas production methods are reviewed across renewable and non-renewable sources, with reaction processes categorized as green, blue, grey, black, pink, and turquoise, depending on the reaction pathway and CO2 emissions management. This review covers the applications of hydrogen technology in petroleum refining, chemical and metrological production, hydrogen fuel cell electric vehicles (HFCEVs), backup power generation, and its use in transportation, space, and aeronautics. It assesses physical and material-based hydrogen storage methods, evaluating their feasibility, performance, and safety, and comparing HFCEVs with battery and gasoline vehicles from environmental and economic perspectives. Finally, the prospects and challenges associated with hydrogen production, handling, storage, transportation, and safety are also discussed.

Yang Qi, Wang Haizhou, Chen Changkui et al.

To solve the problem of large section damage of ø139.7 mm casing in low-permeability reservoirs due to corrosion,small(ø88.9 mm)casing is usually adopted for secondary cementing.However,there is still a possibility of secondary casing damage,and the 76 mm inner diameter of small casing is not convenient for maintenance.In this paper,structural design and full-scale hydrostatic test were conducted on glass fiber reinforced resin(GFRR)based nonmetallic large section sticking-plugging pipe,and the cementing material with narrow gap and high obdurability was selected.The results show that the test pipe meets the field requirements in terms of the pressure bearing performance at different temperatures,and the sealing performance of the pipe body and the threaded connector,and the selected cementing material has a compressive strength of 62 MPa.Supported by appropriate safeguard measures for sticking-plugging operation,a set of sophisticated nonmetallic large section sticking-plugging technology was formed.Field application in 7 wells show that the cementing success rate is 100%,the cementing acceptability is over 99%,and the daily incremental production per well is 3.2 t,indicating remarkable achievements.The proposed technology improves the recovery efficiency of low-permeability reservoirs,and also provides additional option for treatment of casing damaged well.

Dileep Kumar Balaga, Jayanta Mondal, Sandeep D. Kulkarni

Abstract To maintain performance of an aqueous-based drilling muds (ABDMs), it was imperative to understand the decay mechanism of the incorporated synthetic polymers, when exposed to the elevated temperatures. The understanding of the decay mechanism could provide a polymer replenishment strategy for the fluid to retain a specific rheology and filtrate control performance. In this context, thermal-degradation of various acrylamide co-polymers was investigated in different monovalent brines. The acrylamide co-polymers were custom synthesized, and their molecular weight and % sulfonic substitution was verified using the capillary viscometer and nuclear magnetic resonance spectroscopy techniques respectively. The co-polymer thermal degradation mechanism (i.e., polymer hydrolysis) in various monovalent brines (KCl, NaCl and NaBr) was quantified by novel titration for temperature range {121 °C, 177 °C}. The degradation response of the co-polymers was then correlated with their rheology and HPHT (high-pressure-high-temperature) filtrate performance; for instance, the titration studies showed that co-polymer degradation was 12–15% and 44–47% after sixteen hours aging at 121 °C and 177 °C respectively; correspondingly the co-polymer performance in ABDM, exhibited HPHT filtrate of 12–18 mL and 38–40 mL at those respective temperatures after sixteen hours of aging. The quantified understanding of the co-polymer thermal degradation was used to device a new approach for co-polymer replenishment strategy; it was illustrated that a 7% replenishment of the co-polymer for every eight hours, at 121 °C, enabled sustained HPHT filtrate of 12–18 mL for the studied evaluation period of thirty-two hours. The replenishment approach presented in the study would provide a valuable tool for drilling automation to ensure sustained fluid performance.

Shunsuke Tsubaki, Daisuke Niizumi, Daiki Takeuchi et al.

The aim of this research is to refine knowledge transfer on audio-image temporal agreement for audio-text cross retrieval. To address the limited availability of paired non-speech audio-text data, learning methods for transferring the knowledge acquired from a large amount of paired audio-image data to shared audio-text representation have been investigated, suggesting the importance of how audio-image co-occurrence is learned. Conventional approaches in audio-image learning assign a single image randomly selected from the corresponding video stream to the entire audio clip, assuming their co-occurrence. However, this method may not accurately capture the temporal agreement between the target audio and image because a single image can only represent a snapshot of a scene, though the target audio changes from moment to moment. To address this problem, we propose two methods for audio and image matching that effectively capture the temporal information: (i) Nearest Match wherein an image is selected from multiple time frames based on similarity with audio, and (ii) Multiframe Match wherein audio and image pairs of multiple time frames are used. Experimental results show that method (i) improves the audio-text retrieval performance by selecting the nearest image that aligns with the audio information and transferring the learned knowledge. Conversely, method (ii) improves the performance of audio-image retrieval while not showing significant improvements in audio-text retrieval performance. These results indicate that refining audio-image temporal agreement may contribute to better knowledge transfer to audio-text retrieval.

Junjie Chen, Jiebin Yan, Yuming Fang et al.

Category-agnostic pose estimation (CAPE) aims to predict keypoints for arbitrary classes given a few support images annotated with keypoints. Existing methods only rely on the features extracted at support keypoints to predict or refine the keypoints on query image, but a few support feature vectors are local and inadequate for CAPE. Considering that human can quickly perceive potential keypoints of arbitrary objects, we propose a novel framework for CAPE based on such potential keypoints (named as meta-points). Specifically, we maintain learnable embeddings to capture inherent information of various keypoints, which interact with image feature maps to produce meta-points without any support. The produced meta-points could serve as meaningful potential keypoints for CAPE. Due to the inevitable gap between inherency and annotation, we finally utilize the identities and details offered by support keypoints to assign and refine meta-points to desired keypoints in query image. In addition, we propose a progressive deformable point decoder and a slacked regression loss for better prediction and supervision. Our novel framework not only reveals the inherency of keypoints but also outperforms existing methods of CAPE. Comprehensive experiments and in-depth studies on large-scale MP-100 dataset demonstrate the effectiveness of our framework.

Bin Han, Kuang Yu

Recently, machine learning potentials (MLP) largely enhances the reliability of molecular dynamics, but its accuracy is limited by the underlying $\textit{ab initio}$ methods. A viable approach to overcome this limitation is to refine the potential by learning from experimental data, which now can be done efficiently using modern automatic differentiation technique. However, potential refinement is mostly performed using thermodynamic properties, leaving the most accessible and informative dynamical data (like spectroscopy) unexploited. In this work, through a comprehensive application of adjoint and gradient truncation methods, we show that both memory and gradient explosion issues can be circumvented in many situations, so the dynamical property differentiation is well-behaved. Consequently, both transport coefficients and spectroscopic data can be used to improve the density functional theory based MLP towards higher accuracy. Essentially, this work contributes to the solution of the inverse problem of spectroscopy by extracting microscopic interactions from vibrational spectroscopic data.

A. Saqib, Tze-Haw Chan, A. Mikhaylov et al.

Growing energy demand but stagnant production followed by volatile exchange rate leads Pakistan to energy imbalances and potential economic contraction. Yet, studies on sectoral energy imports are limited and inconclusive without accessing the asymmetric effect of currency fluctuations. We examine the impacts of Pakistani rupee volatility on monthly energy imports based on the nonlinear autoregressive distributed lag (NARDL) estimations. Augmented Dickey–Fuller and Phillips–Perron tests were used to conduct unit root testing, and the bound testing approach was used to examine the long-term cointegration. The long-run asymmetry was tested with the Wald test, and using the NARDL model, we examined both short-run and long-run asymmetric effects of exchange rate volatility on energy imports. The bound test was established and supported through E C M t − 1 (t-test), cointegrating the relationship between exchange rate volatility and energy imports in a long term. Among others, both short-run and long-run asymmetric effects were found for crude oil, coal, electricity, and petroleum products. Rupee depreciation increased crude oil and electricity imports, while the appreciation effects were insignificant. Overall, the empirical assessment reveals that the foreign exchange volatility effect is sectoral specific and asymmetric in Pakistan. It offers new insights into re-strategizing the energy policy and refining the import substitution plan.

Tamer Hassan, Ahmad M.K. Basal, Mohammad A. Omran et al.

The main objective of this paper is to construct a static model that compress the uncertainties of the stochastic distribution of the reservoir properties of the Bahariya Formation in Heba field, at the northeastern portion of the Western Desert. This model has been constructed through the integration of the interpretations of the eighteen 2D seismic sections and the analysis of well logs data for four wells (HEBA 300X, E.BAH-E−1X, E.BAH-D-1X, and HEBA 10X) drilled in the study area. This set of data was implemented in a harmonic workflow. Structural framework was the first step created on the basis of the seismic and well log interpretations. Model zonation was mainly managed by the marine flooding events took place during the Cenomanian period. The trapping faults position uncertainty has been compressed through the tying of the seismic profiles with the identified fault cuts in the well data. Effective porosity spectrum was broke up into three reservoir qualities. The results showed heterogeneous facies qualities for oil production in specific five zones in the topmost part of the Bahariya Formation. The effective porosity model was generated stochastically considering the normal distribution for each reservoir quality. Water saturation was distributed by two methods; 1) Sequential Gaussian Simulation that was co-simulated by porosity model. 2) Log-based saturation height function for each reservoir quality. This methodology provided as accurate as possible estimates for the volume calculation by quantifying the sensitivity of the important parameters such as oil contact. Additionally, the model was prepared to be used as a front end for dynamic simulation.

M.G. Gab-Allah, Ahmed H. El-Ged, E.A. Badr et al.

Three Gemini amphiphiles had prepared through reaction of amide of succinic acid with different bromo olefins. Their chemical structure was emphasized different spectroscopic methods. the surface tension measurements were investigated at 20, 40 and 60 °C. The Gemini surfactant with the longest tail clarified enhancement of surface parameters values with elevating mixture temperature.Both (ΔGoads) & (ΔGomic) data are negative, providing spontaneously occurrence of adsorption and micellization processes while the positivity of (ΔSoads) &(ΔSomic) revealing more order for both processes. Thermodynamic behaviour increases by raising chain length. All of fabricated amphiphiles exhibited antimicrobial activity against bacteria and fungi.

Suriatie Mat Yusuf, Radzuan Junin, Mohd Akhmal Muhamad Sidek et al.

The aim of this research is to study the effect of hydrophilic silica nanoparticles, sizes as CO2 foam stabilizer in the presence of nonionic TX100 surfactant. Two nanosilica sizes, 15 and 70 nm, have been examined thoroughly. Physisorption of TX100 on silica nanoparticles (nanosilica) was characterized by adsorption isotherm and surface tension measurement, while CO2 foams stability was quantified based on their foamability, foam stability, particle partitioning in the foams, and bubble sizes. Results show that direct contact of TX100 with nanosilica does altered the wettability of hydrophilic nanosilica surface, enable them to lengthen CO2 foams life at certain surfactant and nanoparticles concentrations. For 15 nm nanosilica, CO2 foam stability shows excellent performance at 0.1 and 0.5 wt% TX100 concentrations. As for 70 nm nanosilica, CO2 foam demonstrates longer lifetime at much lower TX100 concentration, 0.01 wt%. Without the presence of TX100, CO2 foams exhibit undesirable lifetime performances for both nanosilica sizes. Nanosilica partitioning in CO2 foams structures demonstrate consistent relation with contact angle measurement. Estimated bubble sizes shows insignificant effect on CO2 foams life. With the assists of nanosilica and TX100, enhanced oil recovery via CO2 foam injection succeeds in increasing oil production by 13–22% of original oil-in-place (OOIP).

M. Goeree, Eric A. Helland

Every year thousands of firms are engaged in research joint ventures (RJV), where all knowledge gained through R&D is shared among members. Most of the empirical literature assumes members are non-cooperative in the product market. But many RJV members are rivals leaving open the possibility that firms may form RJVs to facilitate product market collusion. We examine this by exploiting variation in RJV formation generated by a policy change that affects the collusive benefits but not the research synergies associated with a RJV. We use data on RJVs formed between 1986 and 2001 together with firm-level information from Compustat to estimate a RJV participation equation. After correcting for the endogeneity of R&D and controlling for RJV characteristics and firm attributes, we find the decision to join is impacted by the policy change. We also find the magnitude is significant: the policy change resulted in an average drop in the probability of joining a RJV of $41\%$ among computer and semiconductor manufacturers, $34\%$ among telecommunications firms, and $33\%$ among petroleum refining firms. Our results are consistent with research joint ventures serving a collusive function.

M. Wahid, S. E. Hosseini, Hasanen M. Hussen et al.

Pengpeng Zhang, Lixiao Zhang, Yan Hao et al.

Abstract: With the increasing urbanization but growing resource scarcities, the securing provision of fundamental resources as food, energy and water (FEW) has become a unique challenge for urban sustainability. This is not only because of continuous demand of resource imports from different regions for urban areas, but also due to the complex interrelationships among FEW systems. In such context, exploring the interactions between FEW resources and economic activities when investigating FEW provisions to meet urban demand through trade is very essential to find effective policy intervention points and priority areas for actions. This paper investigates external binding FEW resource flows with internal certain interlinkages driven by final demand of Beijing city at different nodes along their supply chains, by combing structural path analysis and multi-regional input-output model of China 2010. The results show that the key source regions present overall neighborhood pattern that Hebei, Inner Mongolia, Anhui, Jiangsu, and Shandong near Beijing are the five leading contributors of tran-regional FEW provisions. The top 20 nexus paths are identified and the most important nexus pathways start with the other services in Beijing. Besides this, the critical supply chains appear divergent directions for FEW flows, driven by food, construction and agriculture industries respectively. Moreover, the key nodes mainly concentrate on less developed regions and energy-related sectors. For example, non-metal products manufacturing in Hebei, petroleum refining and coking in Heilongjiang, and coal mining and washing in Inner Mongolia have larger impacts on all of FEW flows across the supply chains. These results are very informative to targeting our efforts to address the urban FEW nexus issue both from the perspective of supply side and demand side.

Debin Xia, Zhengming Yang, Tiening Gao et al.

Abstract Porosity is the most common form of reservoirs, and its size, shape, and connectivity directly affect the capacity of oil and gas storage and production. To study the micro–nano-pore structure characteristics of shale oil reservoirs and quantitatively characterize its heterogeneity, this work uses high-precision high-pressure mercury intrusion (HPMI) experimental techniques to study the micro–nano-pore structure characteristics of shale oil, and based on the experimental data, fractal theory is used to quantitatively characterize its heterogeneity. The results of the study show that the micro–nano-pores in the shale oil reservoir are concentrated and continuous, and the pore radius is mainly distributed among the range of 30–500 nm, nanoscale pores are an important part of the pores of the shale oil reservoir. The fractal dimension of the shale oil reservoir is larger than the fractal dimension of typical tight oil reservoirs, indicating that the heterogeneity of shale oil reservoir is stronger. The research results have some theoretical and practical significance for the production of inter-salt shale oil reservoirs.

Shu Zheng, Liao Dong, Zhao Wensen et al.

For the polymer flooding in offshore oilfields, the mixing performance of the static mixer used for mixing high-concentration polymer mother liquor with high-pressure water greatly affects the oil recovery efficiency. The offshore platform has limited space and load-bearing capacity. To enable the static mixer to efficiently mix high-concentration polymer mother liquor and high-pressure water, a dispersive premixer was developed. Based on the theory of computational fluid mechanics, the fluid flow and mixing in the pipeline were studied through numerical simulation and field test, and compared with the pre-mixing performance of the three-way on the platform. The results of the study show that:high-concentration polymer mother liquor and high-pressure water can be efficiently mixed within 0.60 m of the outlet of the dispersive premixer. The uniformity of polymer solution mixing after the dispersive premixer is added in front of the static mixer on the platform is improved by 14.29%. The dispersive premixer can meet the requirements of polymer flooding for offshore platforms.

Li Huan, Li Peng, Fan Song et al.

As the key equipment of the floating drilling riser system, difficult anti-recoil control test, high cost and uncontrollable risk of the domestic riser tensioner restricts its industrial application process. To reduce the risk of sea trial application and improve the anti-recoil control effect of the riser tensioner, the AMESim software is used as the simulation platform to build models of anti-recoil valve, tensioner, riser string and control systems based on the riser system of a floating drilling platform in South China Sea. The anti-recoil control system is also built to study the influence of control parameters and emergency disconnection time against anti-recoil control. The study results show that the cylinder position-main valve opening control curve is the key factor for the anti-recoil control. Different emergency disconnection times have a great influence on the anti-recoil control effect of the tensioner. To avoid the local bending of the riser string when disconnected, it is recommended to select the emergency disconnection time in the vicinity of the 180° phase of the platform heave curve. The study results can provide a basis for the control logic optimization and sea trial application of the riser tensioner.

Chenjun Huang, Geyun Liu, Yongsheng Ma et al.

The Tahe oilfield, located in the southwest of the Akekule nosing structure, northern Tarim basin, was the most prolific oilfield targeting at the Ordovician carbonate reservoirs in China. The reservoir space was dominant with fracture-cave systems commonly induced by tectonics and karstification. Although hydrocarbon production had proceeded for two decades in the Tahe oilfiled, the control of oil and gas accumulations was still doubtful. In this work, the periodic fluid flow induced by cyclic tectonic stresses was proposed as the mechanism of hydrocarbon migration in the fracture-cave systems of carbonate reservoirs. The fracture networks formed conduits for fluid flow, and the fluid pressure in caves transmitted from stress field provided the driving force. The constitutive equations were established among stresses, fracture densities and flow velocities. Four quasi-3D geological models were constructed to simulate the flow velocities on the Ordovician surface of Akekule nosing structure in the critical tectonic stages. The simulated results supplied indicative information on oil and gas migration and accumulation in the tectonic stages. Combining with the oil and gas charge history, a conceptual model was built to reveal the multi-stage oil and gas charge and accumulation in the Ordovician of Akekule nosing structure. Keywords: Fracture-cave system, Periodic fluid flow, Numerical modeling, Oil and gas accumulation, Akekule nosing structure, Tarim Basin

Ebong D. Ebong, Anthony E. Akpan, Stephen E. Ekwok

Abstract Three-dimensional models of petrophysical properties were constructed using stochastic methods to reduce ambiguities associated with estimates for which data is limited to well locations alone. The aim of this study is to define accurate and efficient petrophysical property models that best characterize reservoirs in the Niger Delta Basin at well locations and predicting their spatial continuities elsewhere within the field. Seismic data and well log data were employed in this study. Petrophysical properties estimated for both reservoirs range between 0.15 and 0.35 for porosity, 0.27 and 0.30 for water saturation, and 0.10 and 0.25 for shale volume. Variogram modelling and calculations were performed to guide the distribution of petrophysical properties outside wells, hence, extending their spatial variability in all directions. Transformation of pillar grids of reservoir properties using sequential Gaussian simulation with collocated cokriging algorithm yielded equiprobable petrophysical models. Uncertainties in petrophysical property predictions were performed and visualized based on three realizations generated for each property. The results obtained show reliable approximations of the geological continuity of petrophysical property estimates over the entire geospace.

Laura Midgley, Luc J. Bourhis, Oleg Dolomanov et al.

We have implemented a procedure that allows the use of non-spherical atomic form factors in a standard crystallographic X-Ray refinement. We outline the procedure for their use, alongside a mathematical justification of their viability.

C. Wannaz, P. Fantke, J. Lane et al.