International Meeting on
Petroleum Engineering
Scientific Program
Keynote Session:
Title: Mechanism for conversion from methane hydrate over to carbon dioxide dominated hydrate during injection of carbon dioxide into methane hydrate filled sediments
Biography:
Bjorn Kvamme has obtained his MSc in Chemical Engineering (1981) and PhD in Chemical Engineering (1984) from the Norwegian University of Technology and Natural Sciences. After a short period with SINTEF and two years at Bergen University College, he was appointed as Full Professor in 1987. He was appointed as a Professor in Gas Processing at the Department of Physics, University of Bergen in 2000. He is the author/co-author of 422 publications during last 25 years, of which 148 are in good international scientific journals.
Abstract:
Huge amounts of methane are trapped in ice-like structures (hydrate) around the world. Estimated amounts vary but the most recent estimates indicate that the energy trapped in these hydrates may be as much as twice the energy of conventional fossil fuels. 99% of these hydrates are almost pure methane hydrate since the dominant sources are biogenic methane form the upper crust. CO2 forms the same structure of hydrate water as methane but the thermodynamic stability of carbon dioxide hydrate is higher. This implies that injection of CO2 into natural methane hydrates in sediments will lead to a conversion of the in situ methane hydrate over to a mixed hydrate dominated by CO2. This is a win-win situation in which the methane is released as energy source while leaving CO2 stored as a solid phase in underground sediments. There are two primary mechanisms that can lead to this conversion. The first of these is a solid state mechanism in which the CO2 gradually replace the filling of methane in primarily the 75% largest water cavities in the structure. This is a very slow process and practically not important. Another mechanism involves the formation of a new hydrate from available free in the sediment pores. This formation process releases heat which will distribute and assist in dissociation of in situ methane hydrate. In order to verify the latest mechanism we utilize Phase Field Theory (PFT) modeling. In simplified terms this corresponds to a minimization of free energy under the constraints of mass- and heat-transport. In this modeling we have placed liquid water of various thickness around and initial hydrate and then sampled the dynamics of the reformation process. It is observed that the more available liquid water around the initial methane hydrate core, the longer and fast conversion is retained. When this initial liquid water layer is consumed the slow mechanism takes over.
Title: PCP2AFE: Algorithms in dual-transforming between corner point grid of PETREL and finite element grid of ANSYS
Biography:
Mao Pan, the honoured dean of school of space and earth sciences, Peking University, director of Institute of Oil and Gas, Peking University. Hisresearch area is mainly focused on the theory and application of petroleum geology, environmental geology and information geology. At present, professor Pan, as the lead (or participation member),has successfullyin completion more than 20 scientific researches and projects(10 projects are by national ministry and province department), received 15 scientific awards (4 awards are ministerial and provincial level), published more than 90 scientific papers and research reportsand 7 abstracts of conference journal.As editor or editorial member professor Pan has already published 11 monograph and textbook.The current research work is mainly related to information geology, 3D GIS, disaster geology and petroleum geology.
Abstract:
Stress distribution analysis is crucial in oil and gas field development, especially in the unconventional oil and gas reservoir which affects the distribution of artificial fracture during hydraulic fracturing. Stress simulation based on finite element analysis is applied because of its flexibility and accuracy. While due to the incompatibility model grid format between software, geological modeling process cannot be effectively integrated with finite element analysis. Here, in face of the aforementioned problems, PCP2AFE software, several algorithms, is developed to fulfill the dual-transforming between corner grid model built by PETREL and finite element grid model generated by ANSYS. A series of models are imported to testify the validity and efficiency of the software, including both structured and unstructured grids with and without heterogeneous Furthermore, with the development of PCP2AFE software, stress simulation process can directly operate based on geological model without re-modeling in finite element analysis software. Also, the simulation results can be re-converted and linked to geological model based on corner point grid for subsequent analysis and as a result to effectively link PETREL and ANSYS software. Initially, the software is developed to perform models dual-transforming built by PETREL and ANSYS, slight modifications can be operated to make some more extensions in linking more software combinations which based on corner point grid and finite element grid. Meanwhile, models from previous are imported to perform the stress field distribution simulation. At last, several important conclusions and discussions for subsequent analysis are included.
Title: Vibration effects on submarine pipelines and steel catenary risers
Biography:
Chiew Yee Meng is currently a Professor in the School of CEE at the Nanyang Technological University, has more than 35 years of research experience in sediment transport, turbulence, hydraulics and coastal/offshore engineering. He particularly is interested in scour at hydraulic structures such as bridge piers, submarine pipelines, monopiles, ship propellers, jets, etc. and how such erosion affects the integrity of the surrounding structures and sediment bed. His research interests also include turbulence effects in fluvial and coastal hydraulics and the influence of seepage on the turbulence characteristics. He has more than 160 archival publications and serves as
an Associate Editor for Journal of Hydraulic Engineering, ASCE and International Journal for Sediment Research. Throughout his career, he has acted as a Specialist Consultant to numerous international and local companies and governmental organizations, offering his expert advice to solve challenging engineering projects.
Abstract:
Submarine pipelines are indispensable features in the offshore and marine industry for conveying hydrocarbons from one location to another. A scour hole may form on an erodible seabed around underwater pipelines due to the action of waves and currents. The development of scour holes can compromise the integrity of pipelines and it often is the main cause of pipeline Consequently, the prediction of pipeline scour is an important design consideration and this subject has been studied extensively for several decades. During the early stages of pipeline research, were devoted to the development of empirical equations for the prediction of 2-dimensional scour depth. In more recent years, research works has progressed investigating the development of 3-dimensional scour hole because the span that forms beneath the pipeline was recognized to be a more important variable in affecting pipeline failure. Notwithstanding the progress, those researches still were confined to a static pipeline. In the past 5 years, the effect of vibration on scour hole development has attracted more attention because the touchdown point of a vibrating steel catenary, for example, likely will have a profound effect on scour hole development. Recent laboratory research findings using a truncated riser subjected to a vertical sinusoidal motion of varying amplitude frequency have shown important variations between static and vibrating pipelines, resulting in the formation of fundamentally different scour profiles. Using both Acoustic Doppler Velocimetry (ADV) Profilers and Particle Image Velocimetry (PIV) techniques to measure the flow, the surrounding flow field is shown to be markedly modified by pipeline and riser vibrations. The augmented fluctuating velocity considerably increases local turbulence, thereby promoting scour. The maximum scour depth increases significantly with both vibration amplitude and frequency, with frequency exerting a more profound influence. This talk presents the state-of-the-art findings on vibration effects on pipeline scour.
Oral Session 1:
- Petroleum Geology | Geophysical Exploration | Hydraulic Fracturing | Advanced Drilling Technologies | Petroleum Refineries | Computer Applications in Petroleum Engineering | Computational Modelling | Petroleum Desulphurization
Chair
Jiang Yang
Xian Petroleum University, China
Title: CO2 minimum miscibility pressure (MMP) correlation predicts slim tube experimental data very precisely
Biography:
Maqsood Iqbal is a Senior Reservoir Engineer with 20 years of diversified experience; skills encompass Reservoir Engineering, enhancedoil recovery (/IOR), Production Operations/Optimization and Petroleum Economics. Exclusive aptitudes; Well Test Analysis (WTA), Decline Curve Analysis (DCA),Material Balance Calculations, Temperature Logs Interpretations, Pressure-Volume-Temperature (PVT) studies, Non-Parametric Regression and Artificial Neural Networks. He holds M.Sc. Petroleum Engineering degree from Kuwait University.
Abstract:
Miscible gas injection is one of the effective enhanced oil recovery (EOR) methods. MMP is the most important parameter to successfully design CO2 flooding, local displacement efficiency from gas injection is also highly MMP dependent, which is traditionally measured through time consuming, expensive and cumbersome experiments. A new CO2 MMP correlation based on multiple-linear-regression modeling technique has been developed to more accurately estimate the CO2 MMP for a wide range of live and heavy crude oils. The proposed CO2 MMP correlation is originated from CO2 MMP data in addition to database from the worldwide published literature that covers 33 pure CO2 MMP data for various live and dead oil samples. The proposed model trained by exploiting 66% (22 data points) of the data bank. This correlation is expressed as a function of temperature, mole fractions of in situ reservoir CO2 along with two of its hydrocarbon components (C1 and C3). A set of experimental data pool from the literature is collected to evaluate and compare the results of the developed correlation with pre-existing correlations through statistical and graphical error analyses. A statistical comparison is performed for both training data set (22 data points) as well as testing data set (11 data points). It is found that the proposed CO2 MMP correlation provides the best reproduction of MMP data with a percentage average absolute error of 11.46% and 11.92% for training and testing categories respectively. Further the correlation coefficient for the proposed correlation for training and testing data are 0.957 and 0.929, respectively. Finally, by employing the relevancy factor, it is found that the after temperature both light and intermediate (C1 and C3) components of crude oil have the most significant impact on the CO2 MMP estimation.
Title: Development of possible leakage pathways for CO2 in between well cement and injection pipeline during injection of CO2 for aquifer storage
Biography:
Bjorn Kvamme has obtained his MSc in Chemical Engineering (1981) and PhD in Chemical Engineering (1984) from the Norwegian University of Technology and Natural Sciences. After a short period with SINTEF and two years at Bergen University College, he was appointed as Full Professor in 1987. He was appointed as a Professor in Gas Processing at the Department of Physics, University of Bergen in 2000. He is the author/co-author of 422 publications during last 25 years, of which 148 are in good international scientific journals.
Abstract:
Aquifer storage of CO2 is one option for reducing CO2 emissions to the atmosphere. Offshore Norway this is being utilized for storing 1 Million ton CO2 per year from the Sleipner hydrocarbon production of hydrocarbons. A slightly smaller amount (0.7 million tons per year) is being stored in another field (Snohvit) offshore Norway. On a nano to micro scale there are flow channels in between the well completion cement and the rusty injection pipeline. During year of CO2 injection water with dissolved CO2 as well as some separate CO2 phase will be dragged into these channels. This can lead to dissolution of the cement minerals, as well as corrosion of the pipeline. As a first step in modeling these processes it is important to understand how water, CO2, H+ and HCO3- will distribute on the surfaces of rust (Hematite is used as a model) and cement. These distributions can then provide a basis for setting up realistic Quantum mechanical modeling for studies of reaction kinetics and associated parameters (activation energies, etc.) needed for kinetic models in reactive flow modeling of the pathways from injection point of the pipeline to the seafloor. It is found that CO2 adsorbs well on cement but not directly on rust. Bicarbonate and H+ adsorbs on both surfaces but compete with water and natural ions in groundwater.
Title: Hydraulic fracturing in soils with immiscible and miscible fluids
Biography:
Hosung Shin has his expertise in development of numerical simulators. He has developed multi-dimensional FEM simulator Geo-COS (Geo-Coupled Simulator) specifically developed to investigate coupled phenomena in porous media and jointed rock-mass subjected to multi-phase flow.
Abstract:
Fluid-driven hydraulic fracturing in soils has been explained either as tensile failure or shear failure. It is in part due to similar fracture pattern and simple explanation from fracture mechanics on solid materials. However, these hypotheses contradict the inherent effective stress frictional behavior of soils and fail to justify experimental observations. In this study, experiments, particle-scale analyses and macro-scale simulation provide unprecedented insight into hydraulic fracture initiation and growth in granular materials. Distinct particle-level analysis develops whether the invading fluid is miscible or immiscible with the host fluid. The miscibility of the invading fluid with the host fluid leads distinct localization processes that depend on the balance between particlelevel skeletal forces (effective stress-dependent), capillary forces (the invasion of the interfacial membrane when immiscible fluids are involved) and seepage drag forces (associated with fluid flow velocity). Positive feedback mechanisms at defects on the soil surface and fracture tips that promote fracture initiation and sustain fracture propagation. These include increased porosity at the tip due to strains preferentially normal to the fracture alignment, either eased membrane invasion (immiscible fluids) or higher hydraulic conductivity (miscible fluids) and the emergence of particle-level forces that promote opening-mode particle displacement. This effective stress compatible sequence of events helps identify the parameters that govern fluid-driven fracture formation in soils, and explain experimental observations.
Title: Elastic seismic imaging using acoustic propagators
Biography:
Yunyue Elita Li has joined the Department of Civil and Environmental Engineering at the National University of Singapore as an Assistant Professor in 2016. She did her Postdoctoral Research at Massachusetts Institute of Technology, holding a joint position in the Earth Resources Laboratory and the Department of Mathematics. She has received her PhD and MS degrees in Geophysics from Stanford University in 2014 and 2010, respectively. She has obtained her BS degree (Highest Honors) in Information and Computational Science from China University of Petroleum, Beijing in 2008.
Abstract:
Elastic wave imaging has been a significant challenge in the exploration industry due to the complexities in wave physics and in numerical implementation. In this paper, we derive the elastic wave equations without the assumptions of homogeneous Lame parameters to capture the mode conversion between the P- and S-waves in an isotropic, constant-density medium. The resulting set of two coupled second-order equations for P- and S-potentials clearly demonstrates that mode conversion only occurs at the discontinuities of the shear modulus. Applying Born approximation to the new equations, we derive PP and PS imaging conditions as the first gradients of waveform matching objective functions. The resulting images are consistent with the perturbations of the elastic parameters and hence are automatically free of the polarity reversal artifacts in the converted images. When implementing reverse time migration (RTM), we show that scalar wave equations can be to back propagate the recorded P-potential, as well as individual components in the vector field of the S-potential. Compared with conventional elastic RTM, the proposed elastic RTM implementation using acoustic propagators not only simplifies the imaging condition, but also reduces the computational cost. We demonstrate the accuracy of the proposed method using both 2D and 3D numerical examples.
Title: Molecular simulations of surfactant-modified interfaces: Numerical tools and analysis
Biography:
Bjorn Kvamme has obtained his MSc in Chemical Engineering (1981) and PhD in Chemical Engineering (1984) from the Norwegian University of Technology and Natural Sciences. He is appointed as a Professor in Gas Processing at the Department of Physics, University of Bergen in March 2000. He is the author/co-author of 422 publications during last 25 years, of which 148 are in good international scientific journals. He has 2270 citations as per May 1, 2017 and has numerous papers at international conferences.
Abstract:
Carbon dioxide is one of the two main components of the alternating water/CO2 flooding technique which has proven highly effective for improving the efficiency of enhanced oil recovery (EOR). However, carbon dioxide from smaller sources, such as CO2 separated from hydrocarbon streams originating in CO2 rich fields, is still considered to be a waste and often released into atmosphere. It is our belief that we can achieve a similar effect via injecting emulsion like mixture of water, CO2 and a dual-action agent. The dual nature of the surface active component refers to its affinity towards both water/CO2 and water/hydrocarbon interfaces. A portion of injected CO2 will remain inside the reservoir and thus safely stored underground, with remaining injected fluids contributing to enhanced petroleum recovery. The proposed approach will be financially feasible for small carbon dioxide sources, while effectively combining CO2 storage with EOR. The success of this technology will rely on pinpointing surfactant candidates with desired properties, i.e., identifying components exhibiting interfacial activity for both interfaces. We have chosen molecular dynamics (MD) as our main scientific tool for evaluation of various surfactant structures, their behavior and relative impact on the interfaces of interest. MD simulations are computationally intensive at relevant system sizes, so we have established a computational framework allowing a desktop to perform at speeds until recently only possible for supercomputers. Benchmarks showed that our consumer-grade desktop with eight core Intel CPU and two Nvidia GPUs routinely outperformed four Cray XE6m supercomputer nodes. Evaluation of surfactants involves sophisticated analysis of MD data describing the interfacial systems. Traditional techniques involving density profiles have proven to be insufficient to capture the structure of roughened interfaces. We have implemented a more advanced method providing a more accurate description of interface involved, allowing us to study about their structure properties in detail.
Title: Natural hydrocarbon reservoir modeling: Advantages and disadvantages of different geostatistical methods for borehole data interpolation
Biography:
Evgeniy Kovalevsky has graduated from the Moscow Physical-Technical Institute and he has completed his Postgraduate study in the Institute of Oceanology of the Russian Academy of Sciences. Further, he has worked in the Department of Geophysics in the Institute of Marine Engineering Geology, Riga. He has also worked in the Central Geophysical Expedition in Moscow, dealing with development of DV-Geo geological modeling system. His area of interests includes geological models of natural hydrocarbon reservoirs, fuzzy geological models, geostatistics, hydrodynamic modeling, abiogenic theory of petroleum origin and has published more than 30 scientific works.
Abstract:
An interpolation of well data require taking into account the following: (1) A geological environment is of a categorical nature and it is thus impossible for the quantitative properties to be interpolated among different categories. The quality of property interpolation in such an environment is controlled by comparing histograms. (2) The interpolated values should represent the actual variability of a geological environment, where the term actual means meeting a certain criterion. This requirement can be achieved only by means of multiple stochastic realizations. Where a variogram is used as a mentioned criterion, the quality of interpolation is controlled by comparing variograms. (3) It is geostatistical techniques that are mostly applied to compute stochastic realizations. In all these methods it is assumed that the geological environment is statistically uniform. Is a real geological environment statistically uniform? Certainly, it is not. So, in stochastic methods, the key to a successful implementation is dividing the interpolated parameter into deterministic (non-random) and random components. (4) The deterministic features of initial well data (trends, categories, anomalous zones, etc.) are not obvious and if not specially marked, will be erased in the realizations. Stochastic realizations are sterile with respect to the deterministic features and for this reason are not preferred by geologists. (5) In order to overcome this sterility, a number of non-classical (heuristic) geostatistical methods have been developed. The object modeling technique generates realizations which include sand bodies of a particular shape. Being able to manage the shape of individual bodies, the geologist however cannot manage the configuration of the set thereof. (6) To enable managing such combinations, multiple-point statistics (MPS) has been introduced and employed. Its heuristics consists in using a training image. Advantages and disadvantages of different geostatistical methods for borehole data interpolation are discussed.
Title: Molecular simulations of surfactant-modified H2O/CO2 and H2O/hydrocarbon interfaces
Biography:
Bjorn Kvamme has obtained his MSc in Chemical Engineering (1981) and PhD in Chemical Engineering (1984) from the Norwegian University of Technology and Natural Sciences. After a short period with SINTEF and two years at Bergen University College, he was appointed as Full Professor in 1987. He was appointed as a Professor in Gas Processing at the Department of Physics, University of Bergen in 2000. He is the author/co author of 422 publications during last 25 years, of which 148 are in good international scientific journals.
Abstract:
Phenomenological continuum theories of Ginzburg-Landau type have been successfully applied before to address complex interfacial phenomena involving emulsion formation in aqueous systems relevant for enhanced oil recovery (EOR). Molecular simulations were proven crucial for calibration of model parameters required to both validate the theory and produce reasonable equation of state. Our molecular simulation work focused on surfactant-modified H2O/CO2 and H2O/oil systems central for an earlier proposed technique that combines EOR and safe storage of carbon dioxide. Viscosity contrast between asphaltenes and the bulk liquids will heavily influence the coalescence of oil droplets and thus offer an alternative, kinetically driven mechanism for emulsion formation and reformation triggered by dual action surfactants. Analysis needed to evaluate the structural details and fluctuations dominating the interfacial regions requires knowing the exact locations of interfaces between all the relevant liquid phases. We have deployed an intuitive technique allowing us to find intrinsic surfaces defining liquid-liquid interfaces through the analysis of instantaneous and time averaged molecular configurations. While fairly straightforward in case of simple liquids, such approach becomes more complicated when the size and the shape of molecules start playing a significant role. We have thus augmented our analysis of large-multicomponent systems by studying several smaller ternary systems with the non-aqueous component varying in size and molecular complexity from carbon dioxide to asphaltenes to investigate the possible impact of different broadening parameters.
Keynote Session:
Title: Fracturing fluid with cellulose nanofiber and viscoelastic surfactant
Biography:
Jiang Yang is a Professor at Xi'an Petroleum University, China. Previously, he has worked in Baker Hughes and PetroChina for over 10 years. His research interests include oilfield chemicals such as corrosion inhibitors, fracturing fluid, surfactant, foam, emulsion, etc. He holds a PhD degree in Chemistry from the University of Missouri-Rolla. He has authored and/or coauthored more than 80 technical papers and holds 40 patents.
Abstract:
The viscoelastic surfactant (VES) fluids have been used in stimulation for many years. VES fluids have low formation damage as it is originated from entanglement of wormlike micelle from selfassociation of small surfactant molecule. In comparison, the metallic cross-linked guar fracturing fluids have residues which cause formation damage. However, VES fluids are used at much higher concentration than that of crosslinked guar fluids. The application of VES fluid is also limited below 130°C. This paper studies a new fracturing fluid based on mixture of cellulose nanofiber and VES with reduced VES concentration and higher temperature limit. The cellulose nanofiber with 4-10 in diameter is an environmental-friendly and biodegradable material, which is the unit in plant cell wall. The VES is an ultralong-chain betaine surfactant. Cellulose nanofibers with hydroxyl group, carboxylate and quaternary derivatives were studied. It was found that the cellulose nanofibers with carboxylate derivatives give better enhancement in viscosity of VES fluid. The more carboxylate group in the cellulose nanofibers is, the higher viscosity in the mixture will be. Addition of 0.2% cellulose nanofibers to 1.4% VES fluid increases the upper temperature limit from 130 to 150°C. In comparison, there is no enhanced and upper temperature limit with conventional cellulose. The increased viscosity and higher temperature limit for the mixed fluid of cellulose nanofiber and VES is due to their cooperative force among hydrogen bonding and electrostatic interaction with nanoscale fiber. The mixed fluid is more shear thinning than cellulose and has high viscosity at low shear rates and low viscosity at high shear rates. This rheological property gives good proppant suspension at flow rate in the fracture and low friction during high shear pumping in the wellbore. The gel can be completely broken by breaker as VES itself. Hence, fluid with cellulose nanofibers and viscoelastic surfactant could be an effective fracturing fluid for fracturing operation.
Oral Session 1:
- Reservoir Engineering & Reservoir Simulation | Advanced Natural Gas Engineering | Petrophysics & Petrochemistry | New frontiers in Petroleum Engineering | Major Challenges in Petroleum Industry | Environmental Impacts in Petroleum Engineering | Petroleum Substitutes | Petroleum Economics
Chair
Mao Pan
Peking University, China
Title: Modeling CO2 hydrate formation during aquifer storage and during storage in CH4 hydrate with associated CH4 production
Biography:
Bjorn Kvamme has obtained his MSc in Chemical Engineering (1981) and PhD in Chemical Engineering (1984) from the Norwegian University of Technology and Natural Sciences. He is appointed as a Professor in Gas Processing at the Department of Physics, University of Bergen in March 2000. He is the author/co-author of 422 publications during last 25 years, of which 148 are in good international scientific journals. He has 2270 citations as per May 1, 2017 and has presented numerous papers at international conferences.
Abstract:
Storing CO2 in aquifers is already a practice offshore Norway and a very promising concept for reducing emissions of CO2 to the atmosphere. Possible future storage reservoir may contain thermodynamic regions of temperature and pressure that
facilitate formation of CO2 hydrate locally. This might be a positive effect since it might reduce vertical migration but the question is whether it also has negative impact on horizontal spreading of CO2 in the reservoir. Another option for underground storage of CO2 is to inject it into CH4 hydrate deposits. CH4 hydrate filled sediments are located worldwide in huge amounts. These hydrates are crystalline structures in which CH4 is entrapped into cavities formed by hydrogen bonded water molecules. CO2 also makes a hydrate with water and the same macroscopic structure as CH4 but with increased thermodynamic stability as compared to CH4 hydrate. Injection of CO2 into hydrate filled sediments will therefor lead to a conversion from the initial CH4 hydrate over to CO2 dominated hydrate with simultaneous release of CH4 gas from the in situ CH4 hydrate. In order to model the two types of systems in realistic reservoir flow situations there is a need for a simulator that can handle non-equilibrium thermodynamics and competing phase transitions which involves hydrate formation and dissociations. (RCB) is the only reservoir simulator for hydrate which handles that so far. The basic feature of the simulator is discussed and relevant examples are presented. In particular we that a reservoir with hydrate formation zones will narrow the CO2 flux both verticsall and horizontally and as such have both positive and negative effects on CO2 storage
Title: PCP2AFE: Algorithms in dual-transforming between corner point grid of PETREL and finite element grid of ANSYS
Biography:
Yuyang Liu has received his Bachelor’s degree of Petroleum Engineering at School of Petroleum Engineering, China University of Petroleum (East) and worked as a visiting student at University of New South Wales. He is now working as PhD candidate at School of Earth and Space Sciences of Peking University and has his expertise in Informational Geology, Petroleum Geology and Petroleum Engineering, in detail, included stress filed simulation, 3D geological modeling and visualizing, self adaption meshing method development, hydraulic fracture simulation and related software development.
Abstract:
Stress distribution analysis is crucial in oil and gas field development, especially in the unconventional oil and gas reservoir which affects the distribution of artificial fracture during hydraulic fracturing. Stress simulation based on finite element analysis is widely applied because of its flexibility and accuracy. While due to the incompatibility model grid format between different software, geological modeling process cannot be effectively integrated with finite element analysis. Here, in face of the aforementioned problems, PCP2AFE software, integrated several algorithms, is developed to fulfill the dual-transforming between corner point grid
model built by PETREL and finite element grid model generated by ANSYS. A series of models are imported to testify the validity and efficiency of the software, including both structured and unstructured grids with and without heterogeneous properties. Furthermore, with the development of PCP2AFE software, stress simulation process can directly operate based on geological model without re-modeling in finite element analysis software. Also, the simulation results can be re-converted and linked to geological model based on corner point grid for subsequent analysis and as a result to effectively link PETREL and ANSYS software. Initially, the software is developed to perform models dual-transforming built by PETREL and ANSYS, slight modifications can be operated to make some more extensions in linking more software combinations which based on corner point grid and finite element grid. Meanwhile, models from previous researches are imported to perform the stress field distribution simulation. At last, important conclusions and discussions for subsequent analysis are included.
Title: Technology of pulse hydraulic fracturing
Biography:
Shipulin Alexander Vladimirovich has completed his graduation from the Leningrad Mining Institute in 1976. He has worked as the Head of the Laboratory and as the Teacher in Mining Institute for 30 years. He has published 130 scientific works, 3 books and holds 96 patents for inventions. Presently, he is an individual Businessman-Researcher
Abstract:
The most effective ways of processing of a well hydraulic fracturing, torpedoing, chemical processing is most expensive, ecologically dangerous technologies. In most cases creation of long cracks of hydraulic fracturing is unprofitable gives low effect and leads to flood. I suggest applying the pulsing hydraulic fracturing pressure to creation of a network of short cracks. The reasons for applying the pulsing hydraulic fracturing pressure are as follows: It is economic, the constant high pressure is not required, powerful pump units are not used, the technology of multistage hydraulic fracturing is not applied, large number of people and equipment is not required, Cracks extend in all directions inflow of oil is carried out from all directions, On it is required to fix cracks proppant. After repeated processing yes the end are not closed by crack pressure. The chemical reactants which are negatively influencing ecology are not applied. Application for production of slate oil and gas is especially effective. Example: The technology of pulse and wave processing for delivery wells which I developed is repeatedly tested on crafts of the Volga region, Kazakhstan and China. For work hoisting works are not used, 2 cars are used, work is carried out by 2 persons. The technology is successfully applied. Together with National Mineral resources university work on creation of hydraulic fracturing in coal layers for preliminary removal of methane is carried out. Calculations which are confirmed with tests are carried out.
Title: Energy recovery from natural gas hydrates: Effect of horizontal flow conduit incorporation on gas and water production
Biography:
Zheng Rong Chong is a PhD candidate in the Department of Chemical and Biomolecular Engineering at the National University of Singapore. His research interest is in the area of experimental investigation on energy recovery from natural gas hydrates.
Abstract:
Natural gas hydrates found beneath permafrost and continental margin have been regarded as a potential source of future energy. Driven by the abundance of hydrate resources (~3000 TCM), a number of scientific production tests and experimental studies have been conducted to elucidate the production behavior from hydrate bearing layers. However, due to the complexity of events that occur simultaneously during hydrate dissociation in porous media (e.g., multiphase transport across porous media of varying porosity, secondary hydrate formation, etc.), the current understanding on the gas and water production behavior from hydrate bearing sediment is still limited. Therefore, more experimental data is required to calibrate the reservoir simulators. In this study, we compared gas and water production kinetics from hydrate bearing sediments with 40% hydrate saturation between no well (N1-N3) and horizontal well (H1-H3) configuration via depressurization. A miniature horizontal production wellbore with multiple boreholes of 2 mm diameter was incorporated within the hydrate bearing sand to investigate how it would alter gas and water production. The surrounding temperature was 281.5 K, and 3 bottom hole pressures (3.5, 4.0 and 4.5 MPa) were experimented. Our experimental results clearly shown that gas and water production kinetics were significantly affected by the incorporation of wellbore: gas production was prolonged to ~10 hour at 4.5 MPa condition; whereas water production ceased within 2 hours-demonstrating that incorporation of flow conduit indeed facilitated gas to flow out of the sediment. For all experimental pressures, the incorporation of horizontal flow conduits (H1-H3) caused an increase in cumulative gas production by ~10% and a decrease in water production by ~20%. The simultaneous increase in gas production and decrease in water production is desirable as water is produced as a by-product during field exploration, consuming pumping power and requiring treatment before its discharge.
Title: Energy recovery from natural gas hydrates: Numerical modeling of natural gas hydrate dissociation in porous media by depressurization with parametric study
Biography:
Zhenuan Yin is a PhD student in the Department of Chemical and Biomolecular Engineering at National University of Singapore. His research interests are in the areas of numerical modeling of natural gas hydrate formation and dissociation kinetic behavior, hydrate reservoir simulator (TOUGH+Hydrate) and multiphase fluids flow in porous media and pipeline.
Abstract:
Natural gas hydrates (NGH) are stable under low temperature and high-pressure conditions. They are abundant in nature located at permafrost and deep-water locations. With the current estimation of ~20,000 trillion cubic meter natural gas trapped in hydrate-form, NGH are considered as a very promising next-generation fuel source. This has provided a strong research impetus for understanding the kinetic behavior of NGH dissociation in porous media and the corresponding gas and water production. In this work, a 2D cylindrical axi-symmetric model was constructed to simulate NGH dissociation in porous media by depressurization method. The simulation domain accurately describes the geometry of the 1.0 L hydrate reactor used in one of our recent experimental studies. The physics involved includes multi-component heat and mass transfer, multi phase fluids flow through porous media and NGH dissociation intrinsic kinetic rate. The initial condition of the simulation is at temperature of 281.4 K and pressure of 6.1 MPa, with pore volume saturation of 40% hydrate, 56% aqueous and 4% gas. The bottom hole pressure of the outlet is maintained at 4.0 MPa during hydrate dissociation. The cumulative gas production is estimated and validated against experimental data, showing a good agreement between observations and numerical predictions. The predictions of the spatial distributions of temperature, hydrate saturation and gas saturation over time show that hydrate dissociates layer by layer with a diffusive hydrate dissociation front. Excess gas from reactor is produced initially before production of gas dissociated from hydrate. In addition, a parametric study on critical heat and fluid transport parameters, i.e. thermal conductivity, intrinsic permeability, are conducted to elucidate their effects on hydrate dissociation and gas production behavior.
Title: Possible application of enhanced oil recovery technology in low permeability carbonate reservoir
Biography:
A Y Zekri has received his BSc, MS and PhD degrees from the University of Southern California, USA. He has spent more than two decades in the petroleum industry. He has worked as a Consultant to the management committees of Waha Oil Co. and Agip Oil Company. He has authored and/or co-authored more than 90 papers on new developments and technical issues in the areas of improved oil recovery, flow through porous media and environmental aspects of petroleum production, petroleum contracts and enhanced oil recovery and has edited and refereed technical papers in widely respected journals. He has also completed a number of research projects in the area of IOR/EOR to UAE and International Petroleum Industries. Currently, he is working as Coordinator of Oil and Gas Technologies, Emirates Center for Energy and Environment Research and Professor of Petroleum Engineering at the United Arab Emirates University.
Abstract:
For low permeability reservoirs (permeability in range of 0.1 to 1 mD), innovative exploration/exploitation strategy is required for optimal hydrocarbon recovery. Many reservoirs or layers discovered have very low permeability. These reservoirs or layers are ignored by local and regional oil companies due to many discoveries of easy oil, i.e., reservoirs with high permeability’s. This project discusses about a low permeability reservoir of AB Field, which has a substantial reserve base and potential for exploration/exploitation. The primary recovery methods are expected not to produce the desired results. Several enhanced oil recovery options are tested through core flooding experiments including sea water flooding, low salinity flooding, surfactant flooding, nitrogen flooding and carbon dioxide injection. Phase behavior studies, contact angle and interfacial tension experiments were performed. Laboratory core flooding indicated that Carbon dioxide flooding is the optimal flooding scheme for the candidate reservoir. Oil price of carbon dioxide sensitivity analysis indicated that a $ 35/bbl is the critical value for the implementation of carbon dioxide flooding for the selected low permeability oil reservoir. Based on the results of our experimental work the following conclusions are reached: Optimum surfactant concentration for our reservoir is 0.3 weight % and Sea water with salinity of 50,000 ppm is the optimum salinity for the selected surfactant. Sea water shows higher displacement efficiency than formation water. Carbon flooding can significantly enhance oil recovery from low permeability formations. Super critical nitrogen gas flooding can lead to higher displacement efficiency than sea water but ultimately recovers less oil than carbon dioxide flooding. Low salinity flooding can be effective in improving the displacement efficiency of low permeability limestone oil reservoir, but requires a good understanding of the complex interactions between rock, brine and oil. Surfactant flooding recovers oil through interfacial tension reduction.
Title: Pressure interference identification and well spacing optimization for a multi-well pad in Zhaotong Shale, China
Biography:
Junlei Wang has received his BS and MS degrees in Petroleum Geology from China University of Geosciences and PhD degree in Petroleum Engineering from Research Institute of Petroleum Exploration & Development, China. His research work focuses on transient-pressure analysis of horizontal well and fractured well, complex fracture network, reservoir characterization and simulation. He has published over 20 papers in the oil and gas development fields.
Abstract:
For the purpose of enhancing recovery and economics of shale resource, it is a critical task for petroleum engineers to determine the optimal well spacing in the industry development of shale play. By using various approaches including analogs, numerical simulation and economic assessment, this paper integrated interference response simulation based on multi-well pattern with history data matching to establish a comprehensive workflow for identifying production interference and optimizing well spacing. The workflow is threefold: first, a general semi-analytical model for the distance of pressure investigation was presented to calculate the interference time through fracture and rock matrix; next, a method of interference measurement was introduced to quantify production interference by searching for changes in buildup trends while wells are staggered on/ production and finally, a numerical model of coupling geological and fracture geometry information was proposed to optimize well spacing in multiple-well pattern with purpose of maximizing the objective function of net present value. Based on typical geological and fracturing properties of Zhaotong Shale, design of experiment method (DoE) was utilized to perform sensitivity study to quantify the rank of important parameters including fracture height, conductivity, length, spacing and distance between neighboring wells, reservoir permeability and porosity with reasonable range. Subsequently, Response Surface Methodology (RSM) was employed to fit a response surface of NPV as the objective function, which provided the optimization results of well placement and fracturing treatment design. The results show that: (1) fracture conductivity is more important in short-term production period, while fracture half-length becomes more significant at long-term production period. And the interaction of fracture length and conductivity is more important than other interaction parameters, (2) there is a potential of decreasing well spacing from current 400~500 m to future 300~400 m, with the increasing the number of production wells by 30% and enhancing recovery of reservoirs by 10% and (3) the value of NPV would increase with the production period elongating, but the optimal well spacing kept constant regardless of the duration of production period. This framework provided guidance for engineers to modify the design of fracturing treatment and to determine the optimal number of horizontal wells for a specified play. In addition, this paper provided further research targets such as the impact of fracture interference, alternative fracturing pattern and drawdown management on the optimization of well spacing.
Title: Research on reservoir characteristics in Zhaotong area Wufeng formation-Longmaxi 11 formation high quality shale
Biography:
He Yuan has received his BS degree in Yangtze University, China and MS degree in Petroleum Engineering from Research Institute of Petroleum Exploration & Development, China. Presently, he is engaged with shale gas geology research in China and focuses on geological characteristics, sedimentary model and reservoir characterization. He has published over 6 papers in the oil and gas development fields.
Abstract:
There are two sets of organic-matter marine shale containing upper Ordovician Wufeng Formation and the lower Silurian Longmaxi Formation in southern China. These resources provide the basis of building several commercial zones of shale gas development. Zhaotong area is in the southern margin of the Sichuan basin, Jianwu syncline south wing. In the area of high quality shale section, thickness of Wufeng and Longmaxi 11 formation ranges from 35 to 40m. By use of well drilling date and core samples, these samples were analyzed throughout incorporating a variety of test methods. The results show that: (1) the content of clay is highest in the mineral composition in the Zhaotong area, average 34.21%, (2) brittleness minerals is quartz the most content, feldspar ranking the 2nd and then calcite, dolomite and a small amount of pyrite, (3) Type II1 dominates in all organic materials, while Type II2 dominates in the upper formation, (4) The maturity of organic matter is on the range of 2~3.5%, reaching a mature stage of generating dry gas, (5) TOC content is about 2.9~14.0% by using actual measurement, average of 7.0%, (6) Logging results show that the porosity of high quality shale is 2.05~5.45%, average of 4.50% and (7) Brittleness index of shale is 54.5~61.1% by calculating the brittleness index, average of 57.4%. The comprehensive results indicate that Wufeng and Longmaxi 11 formations possess the highest brittle mineral content and a larger brittle index, has an enormous potential of hydrocarbon generation and has a larger formation porosity, which demonstrates the practice of establishing a commercial shale plays.
Title: Pendulum swing: Local content requirements in the oil and gas sectors and the law of unintended consequences
Biography:
Berryl Claire Asiago is a Doctoral researcher working in International and European Energy Law in University of Eastern Finland.
Abstract:
The paper considers public policy interventions in the petroleum sector as leverage to further develop and diversify a country’s economy. Specifically, it addresses rules and principles formulated in relation to areas such as employment and the procurement of goods and services that are commonly referred to as local content (LC) requirements in the petroleum sector. These requirements are now among the main challenges facing both companies working within and the governments of natural resource-rich countries, not withstanding the fact that their application has resulted to mixed outcomes. Significantly, the general lack of consideration by governments and international institutions over, pertinent issues such as energy economics and market realities that often exerts a strong influence on interventions to the point that unintended (and often negative) consequences is alarming. Thus, this article argues that although LC, as a form of government intervention, is premised on spill-over effects, it needs to be implemented within the realm of the law of unintended consequences. Thus, governments need to separate those issues that they are realistically able to resolve from those that they cannot by incorporating credible LC requirements. Therefore, this article concludes that ignore the ‘diagnostic model’, which involves the extreme difficulty associated with ensuring efficient policies have actual spill-over effects. Governments embrace short-term rather than long-term remedies to problems and continue to ignore previous experiences of, and detriment caused by, LC requirements, especially when the rules in question are not responsive to an enclave industry such as petroleum.
