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Collaborating Authors
Zhao, Yue
Research on Formation Resistance of Underwater Vehicles Based on CFD
Zhao, Yue (Marine Design & Research Institute of China) | Wan, Wenchao (Marine Design & Research Institute of China) | Peng, Yinghao (Marine Design & Research Institute of China) | Chen, Siyuan (Marine Design & Research Institute of China) | Jiang, Yichen (Dalian University of Technology)
ABSTRACT This study investigates the resistance of underwater vehicles in serial and in parallel formation based on CFD simulations. The influence of hull spacing and the existence of propeller on resistance is analyzed. According to the simulation results, the formation mode of of underwater vehicles with the minimum resistance is suggested, and the resistance of each hull is quantified. The results of this study can provide insights for improving the endurance of underwater vehicles in formation navigation. INTRODUCTION With the rapid development of computer technology, communication technology, battery technology and artificial intelligence technology, AUV, which integrates these technologies, has also been greatly improved and has more application scenarios. For example, in the civil aspect, AUV can conduct submarine survey, underwater search, underwater equipment maintenance, drilling support, etc; On the military side, AUV can conduct underwater reconnaissance, arrange mines, and clear mines. In practical application, endurance is a very important performance index of AUV. It is of great significance for both civil and military AUV to work longer in water and travel longer distances. The resistance of an AUV has a direct impact on its endurance. The smaller the resistance, the longer the endurance. The drag reduction of AUV can be considered from two aspects. On the one hand, the streamlined shape is used to achieve drag reduction through the excellent design of the front and rear shape of the AUV boat (Wang Y.X (2015), Stevenson P et al (2007)). On the other hand, inspired by the formation migration of birds in nature, let multiple auvs in a specific formation form forward, to achieve drag reduction. Many studies have been done on formation resistance of multiple auvs: Muhamad H et al (2009) studied the resistance of two AUV systems with different distances in serial, and also studied the resistance of three AUVs in parallel in a triangular arrangement. The results show that the distance of the hull has little influence on the AUV resistance, while the AUV arrangement has a great influence on the AUV resistance; Pareecha R et al (2014) studied the resistance of two, three and four hulls in parallel with different transverse and longitudinal distances, and divided the spacing into different areas according to the resistance results of the second hulls, and determined the best distance area with the least resistance. These studies provide a theoretical basis for the arrangement of the multi vehicle system, but the current studies are limited to the drag reduction effect under the condition of bare hull. In actual work, there will be a rotating propeller behind the AUV, and the propeller in front of the AUV will produce a complex flow field, which will have a certain impact on the AUV resistance behind. Savas S et al (2018) and Chase N et al (2013) conducted research on the flow field simulation of AUV with propeller propulsion. The results show that the propeller can greatly change the pressure and velocity fields around the AUV, and the CFD calculation results are in good agreement with the experimental results, verifying the accuracy of CFD calculation of the flow field around the self-propulsion AUV. In order to study the drag reduction effect of AUV formation and determine the influence of propeller, this paper uses the CFD method to calculate the resistance of AUV with and without propeller in serial and in parallel formation, and makes a comparative analysis in combination with the flow field.
Deposit Prevention of Mineral Scales Using a Universal Dispersant of Carboxymethyl Cellulose
Ko, Saebom (Department of Civil and Environmental Engineering, Rice University (Corresponding author)) | Zhao, Yue (Department of Civil and Environmental Engineering, Rice University) | Wang, Xin (Department of Civil and Environmental Engineering, Rice University) | Dai, Zhaoyi (Joey) (Hubei Key Laboratory of Critical Zone Evolution, School of Earth Sciences, China University of Geosciences, Wuhan) | Paudyal, Samridhdi (Department of Civil and Environmental Engineering, Rice University) | Dai, Chong (Department of Civil and Environmental Engineering, Rice University) | Kan, Amy (Department of Civil and Environmental Engineering, Rice University) | Tomson, Mason (Department of Civil and Environmental Engineering, Rice University)
Summary As the world’s demands for energy and water increase, innovative technologies have been implemented to produce more energy and water, sometimes in unconventional fields. It brought in new challenges of highly saline water formation and souring of wellbore or formation. Under these circumstances, the conventional threshold inhibition methods might be ineffective in controlling mineral scales. To develop a new feasible method to manage more difficult mineral scale problems, we investigated a single approach to prevent complex mineral scales from deposition using a water-soluble polymer of carboxymethyl cellulose (CMC). We also examine the effect of the combination of conventional threshold scale inhibitors and CMC for complex mineral scale control. Our results showed that a polymeric dispersant of CMC successfully prevented zinc and lead sulfide, barium and calcium sulfate, and calcium and iron carbonate scales from deposition, similar to what we had observed previously with iron sulfide. CMC combined with phosphonate inhibitors of diethylenetriamine penta(methylene phosphonic) acid (DTPMP) or hexamethylene diamine tetra(methylene phosphonic) acid (HDTMP) also enhanced the inhibition performance of phosphonate inhibitors. PbS and ZnS were successfully dispersed in the presence of CMC as low concentrations of CMC as 2 mg/L for PbS and 5 mg/L for ZnS in solution passed through a 1.2-μm pore-size membrane. For barite scale control, the combination of CMC and DTPMP inhibited barite formation for 2 hours, while CMC for only 5 minutes and DTPMP for 18 minutes. The mass of barite deposit on 316 stainless steel was reduced by three-order magnitudes in the combination of DTPMP and CMC, compared with DTPMP alone. The scanning electron microscope (SEM) image of barite precipitated in CMC and DTPMP showed that its morphology was no longer a rhombic plate. According to the transmission electron microscope (TEM) image, the surface of barite was covered by CMC, and after a 6-hour reaction, its size was 45.6 nm, which was slightly larger than that at induction time (10–35 nm). Gypsum crystal formation was also inhibited for at least 6 hours in combining CMC and HDTMP. For calcite scale control in the presence of 20 mg/L of CMC, calcite formations and growth were prevented for 134 minutes, and particle sizes remained in the nanosize range (average particle size of 396 nm) for a 15-hour reaction. Iron carbonate treated with 200 mg/L of CMC-250k and CMC-700k was dispersed for at least 2 hours under our experimental conditions. This study demonstrated that CMC effectively performed as a universal dispersant bringing a new feasible method to manage complex mineral scale problems.
- Materials > Chemicals (1.00)
- Energy > Oil & Gas > Upstream (1.00)
- Water & Waste Management > Water Management > Constituents > Salts/Sulphates/Scales (0.49)
- North America > United States > West Virginia > Appalachian Basin > Marcellus Shale Formation (0.99)
- North America > United States > Virginia > Appalachian Basin > Marcellus Shale Formation (0.99)
- North America > United States > Texas > Permian Basin > Yeso Formation (0.99)
- (27 more...)
Novel Barite Crystallization and Inhibition Model Based on Surface Adsorption
Dai, Zhaoyi (State Key Laboratory of Biogeology and Environmental Geology, School of Earth Sciences, China University of Geosciences) | Zhao, Yue (Department of Civil and Environmental Engineering, Rice University (Corresponding author)) | Wang, Xin (Department of Civil and Environmental Engineering, Rice University) | Kan, Amy T. (Research Institute of Petroleum Processing, SINOPEC) | Tomson, Mason (Department of Civil and Environmental Engineering, Rice University)
Summary Inorganic mineral crystallization is a critical process for numerous industrial and geoengineering processes, including oil and gas production and transportation, geothermal energy exploitation, membrane filtration, cooling tower, heat exchanger, to mention a few. Its unexpected formation can cause significant engineering, economic, and safety issues. Scale inhibitors have been widely used in various geoengineering projects as one of the most efficient and economic methods for mineral scale control. However, after decades of research, the inhibition mechanisms still remain unknown. This study applied a newly developed mechanistic mineral crystallization and inhibition model to barite, one of the most difficult mineral scales to be remediated. This new model assumes that inhibitors prolong the crystallization induction time by adsorbing onto the nucleus surface following a Langmuir-type adsorption isotherm and increasing the surface tension. The new model accurately predicts the barite crystallization induction time without or with 10 commonly used scale inhibitors. More importantly, the adsorption affinity constants (i.e., KL) fitted with the new model from the barite crystallization induction time matched well with those fitted from the direct inhibitor adsorption testing and from measuring barite crystal growth rate changes due to various inhibitors. A good correlation was also observed between the KL values of various inhibitors with barite from this study and those with other minerals (i.e., hydroxyapatite and calcite) from the literature. Such good agreements and correlations validated the adsorption mechanism adopted in the new mechanistic model. This study will deepen the understanding of mineral crystallization and inhibition mechanisms and improve scale management in various industrial and geoengineering processes.
- Europe (0.67)
- North America > United States > Texas (0.46)
- Materials > Chemicals (1.00)
- Energy > Oil & Gas > Upstream (1.00)
- Water & Waste Management > Water Management > Constituents > Salts/Sulphates/Scales (0.59)
A New Kinetic Assay Method for Effective Scale Inhibitor Concentration Determination with Low Detection Limit
Dai, Zhaoyi (Hubei Key Laboratory of Critical Zone Evolution, School of Earth Sciences, China University of Geosciences (Corresponding author) | Ko, Saebom (Equal contributor)) | Wang, Xin (Rice University (Equal contributor)) | Dai, Chong (Rice University) | Paudyal, Samridhdi (Rice University) | Zhao, Yue (Rice University) | Li, Wei (Rice University) | Leschied, Cianna (Rice University) | Yao, Xuanzhu (Rice University) | Lu, Yi-Tsung (Rice University) | Kan, Amy (Rice University) | Tomson, Mason (Rice University)
Summary Scale inhibitors are widely used for mineral scale control in various industries, including oil and gas productions, geothermal energy acquisitions, and heat exchanger scale control to mention a few. In most applications, these scale inhibitors are effective at substoichiometric concentrations (e.g., 1 mg/L or lower), and the optimization of these applications is based on the ability to accurately measure the effective inhibitor concentration at such low concentrations. For example, the continuous treatment injection rate, the squeeze treatment frequency, or the batch treatment schedule need to be optimized to ensure the minimum inhibitor concentration (MIC) is achieved during production. However, the non- or low-phosphorous polymeric scale inhibitor concentration determination is difficult using inductively coupled plasma (ICP)-optic emission spectroscopy/mass spectrometry or ion chromatography, especially at mg/L level concentrations due to their high detection limits. The recently developed hyamine method or high-pressure liquid chromatography (HPLC) method involves intensive labor and high costs. Furthermore, in the complex oilfield operational conditions, the presence of other chemicals (e.g., surfactants, biocides, and corrosion inhibitors), the potential degradation of scale inhibitors and the use of combination scale inhibitors require the measurement of effective scale inhibitor concentration, which cannot be accomplished by the traditional methods. In this study, a new kinetic assay method has been developed to determine the effective scale inhibitor concentration with limits of detection (LODs) less than or around 0.1 mg/L for most cases. This method uses a continuous stirring tank reactor (CSTR) apparatus and is developed based on the linear correlation between the effective inhibition concentration and the measured critical time when laser signal changes. The results show that the inhibitor concentrations of various non- or low-phosphorous polymeric scale inhibitors in synthetic field brine, laboratory solutions, and real oilfield brines can be accurately determined at mg/L level, or lower, with less than 10% error. The method is robust, accurate, and much less time- or labor-consuming than other existing methods especially for non- or low-phosphorous polymeric scale inhibitors.
- Water & Waste Management > Water Management > Water & Sanitation Products (1.00)
- Water & Waste Management > Water Management > Constituents > Salts/Sulphates/Scales (1.00)
- Materials > Chemicals > Specialty Chemicals (1.00)
- Energy > Oil & Gas > Upstream (1.00)
- North America > United States > Texas > Permian Basin > Yeso Formation (0.99)
- North America > United States > Texas > Permian Basin > Yates Formation (0.99)
- North America > United States > Texas > Permian Basin > Wolfcamp Formation (0.99)
- (21 more...)
Laminar structure differences and heterogeneities in reservoirs in continental organic-rich shales: The Cretaceous Nenjiang Formation in the Songliao Basin
Hua, Ganlin (China University of Geoscience (Beijing), China National Petroleum Corporation (CNPC)) | Wu, Songtao (China National Petroleum Corporation (CNPC)) | Zhang, Jinyou (Research Institute of Exploration and Development of Daqing Oilfield Company Ltd.) | Yu, Xinghe (China University of Geoscience (Beijing)) | Guan, Modi (China National Petroleum Corporation (CNPC)) | Zhao, Yue (China University of Geoscience (Beijing), China National Petroleum Corporation (CNPC)) | Liu, Rongchang (China National Petroleum Corporation (CNPC))
Abstract Shale has a unique laminar structure that is currently the focus of considerable interest and a great deal of research in the academic community and industry. Studies have focused primarily on the differences among laminar combinations, whereas only a few have investigated the structure of individual lamina. In this study, we use typical organic-rich shale from the Cretaceous Nenjiang Formation in the Songliao Basin as an example and analyze each individual lamina of the shale on a millimeter scale. We have investigated heterogeneities among the different laminae by using X-ray fluorescence analysis, rock slicing, laser scanning confocal microscopy, field emission scanning electron microscopy, total organic carbon (TOC), rock pyrolysis, X-ray diffraction mineral analysis, electronic computer tomography (nano-CT), nitrogen adsorption, and other experimental methods. Four laminar units — composed of clay minerals, feldspar-quartz, and calcite — are distinguished based on their different levels of Ca, K, and Fe. We designate these units as UA, UB, UC, and UD (from the top to bottom in the formation). The palaeoenvironment, organic geochemical parameters, and mineral compositions of the different laminar structures are “two-stage” in character. From UD to UA, TOC values indicate a slightly decreasing trend, whereas the calcite content indicates a substantial increase, which is related to gradual reduction in the paleodepth, increasing aridity of the climate, increase of salinity, and decrease of reducibility during the sedimentary period. Different laminae correspond to different pore structures. The pore types in units UC and UD are mainly clay mineral-related pores and pyrite intergranular pores. In contrast, calcite dissolution pores are common in units UA and UB. Nitrogen adsorption and nano-CT data indicate that the pore development degree and pore size of organic matter in units UC and UD are better than those of units UA and UB. The porosity of UD is 2.6 times higher than that of UA. Laminae have an important influence on shale quality. The traditional approach to shale evaluation takes laminar combinations in shale strata as the research unit. Switching the focus to the heterogeneity of individual lamina could help in the selection of “sweet spots” and identification of optimal locations for shale oil exploration and development.
- Asia > China > Heilongjiang Province (0.85)
- North America > United States > Texas (0.67)
- North America > United States > North Dakota (0.67)
- Phanerozoic > Paleozoic (1.00)
- Phanerozoic > Mesozoic > Cretaceous (1.00)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock > Mudrock > Shale (1.00)
- Geology > Mineral (1.00)
- Materials (1.00)
- Energy > Oil & Gas > Upstream (1.00)
- Government > Regional Government > Asia Government > China Government (0.47)
- Government > Regional Government > North America Government > United States Government (0.46)
- South America > Argentina > Patagonia > Neuquén > Neuquen Basin > Vaca Muerta Shale Formation (0.99)
- North America > United States > West Virginia > Appalachian Basin > Utica Shale Formation (0.99)
- North America > United States > Texas > Fort Worth Basin > Barnett Shale Formation (0.99)
- (22 more...)
- Reservoir Description and Dynamics > Unconventional and Complex Reservoirs > Shale oil (1.00)
- Reservoir Description and Dynamics > Unconventional and Complex Reservoirs > Shale gas (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Exploration, development, structural geology (1.00)
- (2 more...)
Comparisons of pyrolysis parameters between source rocks and their clay-sized fractions: Implication for source material of hydrocarbon generation
Zhu, Xiaojun (Tongji University) | Cai, Jingong (Tongji University) | Liu, Feng (SINOPEC) | Zhou, Qisheng (Tongji University) | Zhao, Yue (Tongji University, Qilu University of Technology (Shandong Academy of Sciences)) | Dong, Zhe (Shanghai Branch of CNOOC Ltd.) | Liu, Qing (SINOPEC) | Li, Zheng (SINOPEC)
Abstract In natural environments, organic-clay interactions are strong and cause organo-clay composites (a combination between organic matter [OM] and clay minerals) to be one of the predominant forms for OM occurrence, and their interactions greatly influence the hydrocarbon (HC) generation of OM within source rocks. However, despite occurring in nature, dominating the OM occurrence, and having unique HC generation ways, organo-clay composites have rarely been investigated as stand-alone petroleum precursors. To improve this understanding, we have compared the Rock-Eval pyrolysis parameters derived from more than 100 source rocks and their corresponding <2 μm clay-sized fractions (representing organo-clay composites). The results show that all of the Rock-Eval pyrolysis parameters in bulk rocks are closely positively correlated with those in their clay-sized fractions, but in clay-sized fractions the quality of OM for HC generation is poorer, in that the pyrolysable organic carbon levels and hydrogen index values are lower, whereas the residual organic carbon levels are higher than those in bulk rocks. Being integrated with the effects of organic-clay interactions on OM occurrence and HC generation, our results suggest that organo-clay composites are stand-alone petroleum precursors for HC generation occurring in source rocks, even if the source rocks exist in great varieties in their attributes. Our source material for HC generation comprehensively integrates the original OM occurrence and HC generation behavior in natural environments, which differs from kerogen and is much closer to the actual source material of HC generation in source rocks, and it calls for further focus on organic-mineral interactions in studies of petroleum systems.
- Geology > Mineral > Silicate > Phyllosilicate (1.00)
- Geology > Geological Subdiscipline > Geochemistry (1.00)
- Geology > Geological Subdiscipline > Economic Geology > Petroleum Geology (1.00)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock > Mudrock > Shale (0.31)
- North America > United States > Oklahoma > Anadarko Basin > Cana Woodford Shale Formation (0.99)
- Asia > China > Shandong > North China Basin > Shengli Field (0.99)
- Asia > China > Bohai Basin (0.99)
Deposit Prevention of Mineral Scales Using a Universal Dispersant of Carboxymethyl Cellulose
Ko, Saebom (Department of Civil and Environmental Engineering, Rice University (Corresponding author)) | Zhao, Yue (Department of Civil and Environmental Engineering, Rice University) | Wang, Xin (Department of Civil and Environmental Engineering, Rice University) | Dai, Zhaoyi (Joey) (Hubei Key Laboratory of Critical Zone Evolution, School of Earth Sciences, China University of Geosciences, Wuhan) | Paudyal, Samridhdi (Department of Civil and Environmental Engineering, Rice University) | Dai, Chong (Department of Civil and Environmental Engineering, Rice University) | Kan, Amy (Department of Civil and Environmental Engineering, Rice University) | Tomson, Mason (Department of Civil and Environmental Engineering, Rice University)
Summary As the world’s demands for energy and water increase, innovative technologies have been implemented to produce more energy and water, sometimes in unconventional fields. It brought in new challenges of highly saline water formation and souring of wellbore or formation. Under these circumstances, the conventional threshold inhibition methods might be ineffective in controlling mineral scales. To develop a new feasible method to manage more difficult mineral scale problems, we investigated a single approach to prevent complex mineral scales from deposition using a water-soluble polymer of carboxymethyl cellulose (CMC). We also examine the effect of the combination of conventional threshold scale inhibitors and CMC for complex mineral scale control. Our results showed that a polymeric dispersant of CMC successfully prevented zinc and lead sulfide, barium and calcium sulfate, and calcium and iron carbonate scales from deposition, similar to what we had observed previously with iron sulfide. CMC combined with phosphonate inhibitors of diethylenetriamine penta(methylene phosphonic) acid (DTPMP) or hexamethylene diamine tetra(methylene phosphonic) acid (HDTMP) also enhanced the inhibition performance of phosphonate inhibitors. PbS and ZnS were successfully dispersed in the presence of CMC as low concentrations of CMC as 2 mg/L for PbS and 5 mg/L for ZnS in solution passed through a 1.2-μm pore-size membrane. For barite scale control, the combination of CMC and DTPMP inhibited barite formation for 2 hours, while CMC for only 5 minutes and DTPMP for 18 minutes. The mass of barite deposit on 316 stainless steel was reduced by three-order magnitudes in the combination of DTPMP and CMC, compared with DTPMP alone. The scanning electron microscope (SEM) image of barite precipitated in CMC and DTPMP showed that its morphology was no longer a rhombic plate. According to the transmission electron microscope (TEM) image, the surface of barite was covered by CMC, and after a 6-hour reaction, its size was 45.6 nm, which was slightly larger than that at induction time (10–35 nm). Gypsum crystal formation was also inhibited for at least 6 hours in combining CMC and HDTMP. For calcite scale control in the presence of 20 mg/L of CMC, calcite formations and growth were prevented for 134 minutes, and particle sizes remained in the nanosize range (average particle size of 396 nm) for a 15-hour reaction. Iron carbonate treated with 200 mg/L of CMC-250k and CMC-700k was dispersed for at least 2 hours under our experimental conditions. This study demonstrated that CMC effectively performed as a universal dispersant bringing a new feasible method to manage complex mineral scale problems.
- Materials > Chemicals (1.00)
- Energy > Oil & Gas > Upstream (1.00)
- Water & Waste Management > Water Management > Constituents > Salts/Sulphates/Scales (0.49)
- North America > United States > West Virginia > Appalachian Basin > Marcellus Shale Formation (0.99)
- North America > United States > Virginia > Appalachian Basin > Marcellus Shale Formation (0.99)
- North America > United States > Texas > Permian Basin > Yeso Formation (0.99)
- (27 more...)
A New Mechanistic Model for Mineral Crystallization and Inhibition Kinetics and Its Application to Celestite
Zhao, Yue (Rice University) | Dai, Zhaoyi (Rice University (Corresponding author)) | Wang, Xin (Rice University) | Dai, Chong (Rice University) | Paudyal, Samridhdi (Rice University) | Ko, Saebom (Rice University) | Kan, Amy T. (Rice University) | Tomson, Mason (Rice University)
Summary Scale inhibitors are frequently used to control the mineral scale formations during industrial processes. However, few kinetic models with a mechanistic understanding of the inhibition mechanism have been developed. In this study, a new mechanistic model is developed to predict the kinetics of the mineral scale crystallization with and without inhibitors. In this new model, it is proposed that the inhibitors can adsorb on the nucleus surfaces following a Langmuir type isotherm and increase the nucleus interfacial energy, resulting in the prolongation of the induction time. The new model is applied to predict the crystallization and inhibition kinetics of celestite, which has been observed more frequently during various industrial processes with few quantitative models developed. The predicted induction times show close agreement with the experimental data produced in this study. Moreover, the fitted Langmuir-type adsorption reaction constant between celestite and the three inhibitors is comparable with the reported values in the previous studies, implying the reliability of the proposed inhibition mechanism of this new model. This new mechanistic model could be widely adopted in various disciplines, such as elucidation of the inhibition mechanisms, predicting the minimum inhibitor concentration, or new scale inhibitors design guidance, to mention a few.
- Asia > Middle East > UAE (0.28)
- North America > United States > Texas (0.28)
- North America > United States > New Jersey (0.28)
- Materials > Chemicals (1.00)
- Energy > Oil & Gas > Upstream (1.00)
- Government > Regional Government (0.93)
- Water & Waste Management > Water Management > Constituents > Salts/Sulphates/Scales (0.57)
- Reservoir Description and Dynamics (1.00)
- Production and Well Operations > Production Chemistry, Metallurgy and Biology > Inhibition and remediation of hydrates, scale, paraffin / wax and asphaltene (1.00)
- Facilities Design, Construction and Operation > Flow Assurance > Solids (scale, sand, etc.) (1.00)
Dispatch Optimization of Maritime Rescue Forces in Arctic Shipping Based on the Comparison of TOPSIS and the Weighted Scoring Method
Chen, Yinglong (Naval Architecture and Ocean Engineering College, Dalian Maritime University, Dalian / State Key Laboratory of Fluid Power and Mechatronic Systems, Zhejiang University, Hangzhou) | Li, Jun (Naval Architecture and Ocean Engineering College, Dalian Maritime University, Dalian) | Hao, Xinjuan (Naval Architecture and Ocean Engineering College, Dalian Maritime University, Dalian) | Zhao, Yue (Naval Architecture and Ocean Engineering College, Dalian Maritime University, Dalian) | Gong, Yongjun (Naval Architecture and Ocean Engineering College, Dalian Maritime University, Dalian)
ABSTRACT In order to improve the emergency handling ability of Marine rescue in the Arctic, this paper proposes to use TOPSIS (Technique for order preference by similarity to ideal solution) and the Weighted scoring method, respectively, to identify the dispatching rank of Marine rescue forces. By comparing the two methods of dispatch sorting result, the better method is identified. Firstly, according to the environmental characteristics of the Arctic, the evaluation indexes of the dispatching rescue force is selected, and the weight coefficient of the evaluation indexes is determined comprehensively by the AHP (Analytic hierarchy process) and the Entropy weight method; Then, a typical accident situation in the Arctic Sea is set up, and the Weighted scoring method and TOPSIS are used to rank maritime rescue forces stationed in Murmansk respectively. Finally, taking the rank results obtained by the Weighted scoring method as a reference, the rank results obtained by TOPSIS are compared with it. It is concluded that the rescue forces dispatch rank obtained by TOPSIS is more reasonable, which shows that TOPSIS can effectively be used to identify the selection of rescue forces and provide valuable advice to the Arctic Maritime authorities on their search and rescue operations in the Arctic Sea. INTRODUCTION The accelerated melting of Arctic Sea ice is making Arctic shipping lanes more open and polar operations are growing rapidly (Rottem, 2013). In the Arctic region, the environment is cold and harsh, and maritime accidents on ships seriously affect the safety of people on board. Therefore, it is urgent to enhance effective and quick maritime rescue (James and David, 2019). In order to ensure safe operation of polar shipping, scientific research, resource development and other activities, we should improve the efficiency of rescue and support operations, and minimize the risk of accidents (Bercha, 2006). It is necessary to carry out research on polar rescue forces dispatch, so as to achieve the optimal rescue effect in the shortest time.
- Asia > China (0.48)
- Europe > Russia > Northwestern Federal District > Murmansk Oblast > Murmansk (0.26)
Zinc Sulfide Solubility Modeling in Aqueous Solution at High Temperature, Pressure, and Ionic Strength
Wang, Xin (Rice University - Brine Chemistry Consortium) | Dai, Zhaoyi (Rice University - Brine Chemistry Consortium) | Zhao, Yue (Rice University - Brine Chemistry Consortium) | Dai, Chong (Rice University - Brine Chemistry Consortium) | Ko, Saebom (Rice University - Brine Chemistry Consortium) | Paudyal, Samridhdi (Rice University - Brine Chemistry Consortium) | Yao, Xuanzhu (Rice University - Brine Chemistry Consortium) | Leschied, Cianna (Rice University - Brine Chemistry Consortium) | Kan, Amy T. (Rice University - Brine Chemistry Consortium) | Tomson, Mason B. (Rice University - Brine Chemistry Consortium)
Abstract In this study, the solubility of zinc sulfide has been collected from the literature at pH 2 to 11, temperature 23 to 250 °C, pressure 0.6 to 150 bar, and ionic strength 0 to 4.6 m. A solubility model has been developed based on the combination of Pitzer theory calculated activity coefficient and speciation of the Zn-HS-OH-Cl aqueous system. In total, around 230 solubility data were collected as the input database, the model was fitted in Matalab 2020a with the particle-swarm optimization. The updated model is able to predict the ZnS solubility saturation index (SI) with 95% confidence interval 0.04 SI unit, which suggested good accuracy under model conditions. Due to the extremely low solubility of the ZnS itself, these errors correspond to only around 0.07 ppm of [Zn(II)], which is less than the error of measurement for field samples. For all pH conditions, Zn-HS complexes and Zn-Cl complexes have strong influence on the aqueous soluble zinc solubility. This new model with accurate ZnS solubility prediction will help field operators to better control the ZnS scaling and corrosion problem. Introduction The increasing need for fossil fuels has resulted in more aggressive drilling and exploitation in oil and gas production industry . As new explorations at more extreme conditions (i.e. high temperature and high pressure) become more frequent, new challenges arise in terms of drilling equipment, operation conditions and safe production . Among those challenges, the mineral scale deposition, as one of the serious problems both for the surface and subsurface oilfields, can cause pipelines plugging, equipment failure and decrease in production efficiency, even emergency shutdown . Compared to the conventional drilling conditions, the scaling problems in these extreme conditions are mainly caused by changes in temperature and pressure during the production. The rapid temperature and pressure drop from the reservoir to the surface: 1. alters the equilibrium of the ions in the formation water; 2. causes water evaporation; and 3. redistributes the balance with CO2 and/or H2S gases. These changes result in mineral scale formation .
- North America > United States (1.00)
- Europe > United Kingdom > North Sea (0.29)
- Research Report > New Finding (0.89)
- Research Report > Experimental Study (0.54)
- Europe > United Kingdom > North Sea > Central North Sea > Central Graben > Block 29/5b > Elgin Franklin Field > Fulmar Formation (0.99)
- Europe > United Kingdom > North Sea > Central North Sea > Central Graben > Block 22/30c > Elgin Franklin Field > Fulmar Formation (0.99)
- Europe > United Kingdom > North Sea > Central North Sea > Central Graben > Block 22/30b > Elgin Franklin Field > Fulmar Formation (0.99)
- (3 more...)