Download or read book CHaracterization of in Situ Hydrates and the Experimental Measurement of the Rate of Methane Hydrate Dissociation written by Jeffrey W. Ullerich and published by . This book was released on 1985 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Masters Theses in the Pure and Applied Sciences written by Wade H. Shafer and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 414 pages. Available in PDF, EPUB and Kindle. Book excerpt: Masters Theses in the Pure and Applied Sciences was first conceived, published, SIld disseminated by the Center for Information and Numerical Data Analysis and Synthesis (CINDAS) * at Purdue University in 1957, starting its coverage of theses with the academic year 1955. Beginning with Volume 13, the printing and dissemination phases of the activity were transferred to University Microfilms/Xerox of Ann Arbor, Michigan, with the thought that such an arrangement would be more beneficial to the academic and general scientific and technical community. After five years of this joint undertaking we had concluded that it was in the interest of all con cerned if the printing and distribution of the volumes were handled by an interna and broader dissemination. tional publishing house to assure improved service Hence, starting with Volume 18, Masters Theses in the Pure and Applied Sciences has been disseminated on a worldwide basis by Plenum Publishing Cor poration of New York, and in the same year the coverage was broadened to include Canadian universities. All back issues can also be ordered from Plenum. We have reported in Volume 30 (thesis year 1985) a total of 12,400 theses titles from 26 Canadian and 186 United States universities. We are sure that this broader base for these titles reported will greatly enhance the value of this important annual reference work.
Download or read book Natural Gas Hydrates written by Yuguang Ye and published by Springer Science & Business Media. This book was released on 2012-09-11 with total page 407 pages. Available in PDF, EPUB and Kindle. Book excerpt: “Natural Gas Hydrates: Experimental Techniques and Their Applications” attempts to broadly integrate the most recent knowledge in the fields of hydrate experimental techniques in the laboratory. The book examines various experimental techniques in order to provide useful parameters for gas hydrate exploration and exploitation. It provides experimental techniques for gas hydrates, including the detection techniques, the thermo-physical properties, permeability and mechanical properties, geochemical abnormalities, stability and dissociation kinetics, exploitation conditions, as well as modern measurement technologies etc. This book will be of interest to experimental scientists who engage in gas hydrate experiments in the laboratory, and is also intended as a reference work for students concerned with gas hydrate research. Yuguang Ye is a distinguished professor of Experimental Geology at Qingdao Institute of Marine Geology, China Geological Survey, China. Professor Changling Liu works at the Qingdao Institute of Marine Geology, China Geological Survey, China.
Download or read book In Situ Sampling and Characterization of Naturally Occurring Marine Methane Hydrate Using the D written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The primary accomplishments of the JOI Cooperative Agreement with DOE/NETL in this quarter were the deployment of tools and measurement systems for testing on ODP Leg 201, which is intended to study hydrate deposits on the Peru margin as part of other scientific investigations. Additional accomplishments were related to the continuing evolution of tools and measurements systems in preparation for deployment on ODP Leg 204, Hydrate Ridge, offshore Oregon in July 2002. The design for PCS Gas Manifold was finalized and parts were procured to assemble the gas manifold and deploy this system with the Pressure Core Sampler (PCS) tool on ODP Leg 201. The PCS was deployed 17 times during ODP Leg 201 and successfully retrieved cores from a broad range of lithologies and sediment depths along the Peru margin. Eleven deployments were entirely successful, collecting between 0.5 and 1.0 meters of sediment at greater than 75% of hydrostatic pressure. The PCS gas manifold was used in conjunction with the Pressure Core Sampler (PCS) throughout ODP Leg 201 to measure the total volume and composition of gases recovered in sediment cores associated with methane hydrates. The results of these deployments will be the subject of a future progress report. The FUGRO Pressure Corer (FPC), one of the HYACE/HYACINTH pressure coring tools, and two FUGRO engineers were deployed on the D/V JOIDES Resolution during ODP Legs 201 to field-test this coring system at sites located offshore Peru. The HYACINTH project is a European Union (EU) funded effort to develop tools to characterize methane hydrate and measure physical properties under in-situ conditions. The field-testing of these tools provides a corollary benefit to DOE/NETL at no cost to this project. The opportunity to test these tools on the D/V JOIDES Resolution was negotiated as part of a cooperative agreement between JOI/ODP and the HYACINTH partners. The DVTP, DVTP-P, APC-methane, and APC-Temperature tools (ODP memory tools) were deployed onboard the R/V JOIDES Resolution and used extensively during ODP Leg 201. Preliminary results indicate successful deployments of these tools. An infrared-thermal imaging system (IR-TIS) was delivered to JOI/ODP for testing and use on ODP Leg 201 to identify methane hydrate intervals in the recovered cores. The results of these experiments will be the subject of a future progress report. This report presents an overview of the primary methods used for deploying the ODP memory tools and PCS on ODP Leg 201 and the preliminary operational results of this leg. Discussions regarding the laboratory analysis of the recovered cores and downhole measurements made during these deployments will be covered in a future progress report.
Download or read book Gas Hydrates 1 written by Daniel Broseta and published by John Wiley & Sons. This book was released on 2017-08-07 with total page 309 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gas hydrates, or clathrate hydrates, are crystalline solids resembling ice, in which small (guest) molecules, typically gases, are trapped inside cavities formed by hydrogen-bonded water (host) molecules. They form and remain stable under low temperatures – often well below ambient conditions – and high pressures ranging from a few bar to hundreds of bar, depending on the guest molecule. Their presence is ubiquitous on Earth, in deep-marine sediments and in permafrost regions, as well as in outer space, on planets or comets. In addition to water, they can be synthesized with organic species as host molecules, resulting in milder stability conditions: these are referred to as semi-clathrate hydrates. Clathrate and semi-clathrate hydrates are being considered for applications as diverse as gas storage and separation, cold storage and transport and water treatment. This book is the first of two edited volumes, with chapters on the experimental and modeling tools used for characterizing and predicting the unique molecular, thermodynamic and kinetic properties of gas hydrates (Volume 1) and on gas hydrates in their natural environment and for potential industrial applications (Volume 2).
Download or read book Natural Gas Hydrates written by Yuguang Ye and published by Springer Science & Business Media. This book was released on 2012-09-14 with total page 407 pages. Available in PDF, EPUB and Kindle. Book excerpt: “Natural Gas Hydrates: Experimental Techniques and Their Applications” attempts to broadly integrate the most recent knowledge in the fields of hydrate experimental techniques in the laboratory. The book examines various experimental techniques in order to provide useful parameters for gas hydrate exploration and exploitation. It provides experimental techniques for gas hydrates, including the detection techniques, the thermo-physical properties, permeability and mechanical properties, geochemical abnormalities, stability and dissociation kinetics, exploitation conditions, as well as modern measurement technologies etc. This book will be of interest to experimental scientists who engage in gas hydrate experiments in the laboratory, and is also intended as a reference work for students concerned with gas hydrate research. Yuguang Ye is a distinguished professor of Experimental Geology at Qingdao Institute of Marine Geology, China Geological Survey, China. Professor Changling Liu works at the Qingdao Institute of Marine Geology, China Geological Survey, China.
Download or read book In Situ Sampling and Characterization of Naturally Occurring Marine Methane Hydrate Using the D V JOIDES Resolution written by Frank R. Rack and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Cooperative Agreement DE-FC26-01NT41329 between Joint Oceanographic Institutions and DOE-NETL was divided into two phases based on successive proposals and negotiated statements of work pertaining to activities to sample and characterize methane hydrates on ODP Leg 204 (Phase 1) and on IODP Expedition 311 (Phase 2). The Phase 1 Final Report was submitted to DOE-NETL in April 2004. This report is the Phase 2 Final Report to DOE-NETL. The primary objectives of Phase 2 were to sample and characterize methane hydrates using the systems and capabilities of the D/V JOIDES Resolution during IODP Expedition 311, to enable scientists the opportunity to establish the mass and distribution of naturally occurring gas and gas hydrate at all relevant spatial and temporal scales, and to contribute to the DOE methane hydrate research and development effort. The goal of the work was to provide expanded measurement capabilities on the JOIDES Resolution for a dedicated hydrate cruise to the Cascadia continental margin off Vancouver Island, British Columbia, Canada (IODP Expedition 311) so that hydrate deposits in this region would be well characterized and technology development continued for hydrate research. IODP Expedition 311 shipboard activities on the JOIDES Resolution began on August 28 and were concluded on October 28, 2005. The statement of work for this project included three primary tasks: (1) research management oversight, provided by JOI; (2) mobilization, deployment and demobilization of pressure coring and core logging systems, through a subcontract with Geotek Ltd.; and, (3) mobilization, deployment and demobilization of a refrigerated container van that will be used for degassing of the Pressure Core Sampler and density logging of these pressure cores, through a subcontract with the Texas A & M Research Foundation (TAMRF). Additional small tasks that arose during the course of the research were included under these three primary tasks in consultation with the DOE-NETL Program Manager. All tasks outlined in the original statement of work were accomplished except for the deployment and use of the X-ray CT system under Subtask 2-2. This reduction in scope provided resources that were applied to other activities to support the overall project. Post-expedition analysis of results and report writing will continue beyond this reporting period, however, all field deployments associated with this project have been successfully concluded as of this writing.
Download or read book Gas Hydrates 2 written by Livio Ruffine and published by John Wiley & Sons. This book was released on 2018-04-16 with total page 387 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gas hydrates in their natural environment and for potential industrial applications (Volume 2).
Download or read book Advances in the Study of Gas Hydrates written by Charles E. Taylor and published by Springer Science & Business Media. This book was released on 2007-05-08 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book had its genesis in a symposium on gas hydrates presented at the 2003 Spring National Meeting of the American Institute of Chemical Engineers. The symposium consisted of twenty papers presented in four sessions over two days. Additional guest authors were invited to provide continuity and cover topics not addressed during the symposium. Gas hydrates are a unique class of chemical compounds where molecules of one compound (the guest material) are enclosed, without bonding chemically, within an open solid lattice composed of another compound (the host material). These types of configurations are known as clathrates. The guest molecules, u- ally gases, are of an appropriate size such that they fit within the cage formed by the host material. Commonexamples of gas hydrates are carbon dioxide/water and methane/water clathrates. At standard pressure and temperature, methane hydrate contains by volume 180 times as much methane as hydrate. The United States Geological Survey (USGS) has estimated that there is more organic carbon c- tained as methane hydrate than all other forms of fossil fuels combined. In fact, methane hydrates could provide a clean source of energy for several centuries. Clathrate compounds were first discovered in the early 1800s when Humphrey Davy and Michael Faraday were experimenting with chlorine-water mixtures.
Download or read book Gas Hydrates 2 written by Livio Ruffine and published by John Wiley & Sons. This book was released on 2018-06-19 with total page 389 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gas hydrates in their natural environment and for potential industrial applications (Volume 2).
Download or read book Methane Gas Hydrate written by Ayhan Demirbas and published by Springer Science & Business Media. This book was released on 2010-02-28 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gas hydrates represent one of the world’s largest untapped reservoirs of energy and, according to some estimates, have the potential to meet global energy needs for the next thousand years. "Methane Gas Hydrate" examines this potential by focusing on methane gas hydrate, which is increasingly considered a significant source of energy. "Methane Gas Hydrate" gives a general overview of natural gas, before delving into the subject of gas hydrates in more detail and methane gas hydrate in particular. As well as discussing methods of gas production, it also discusses the safety and environmental concerns associated with the presence of natural gas hydrates, ranging from their possible impact on the safety of conventional drilling operations to their influence on Earth’s climate. "Methane Gas Hydrate" is a useful reference on an increasingly popular energy source. It contains valuable information for chemical engineers and researchers, as well as for postgraduate students.
Download or read book Controls on Gas Hydrate Formation and Dissociation written by Miriam Kastner and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The main objectives of the project were to monitor, characterize, and quantify in situ the rates of formation and dissociation of methane hydrates at and near the seafloor in the northern Gulf of Mexico, with a focus on the Bush Hill seafloor hydrate mound; to record the linkages between physical and chemical parameters of the deposits over the course of one year, by emphasizing the response of the hydrate mound to temperature and chemical perturbations; and to document the seafloor and water column environmental impacts of hydrate formation and dissociation. For these, monitoring the dynamics of gas hydrate formation and dissociation was required. The objectives were achieved by an integrated field and laboratory scientific study, particularly by monitoring in situ formation and dissociation of the outcropping gas hydrate mound and of the associated gas-rich sediments. In addition to monitoring with the MOSQUITOs, fluid flow rates and temperature, continuously sampling in situ pore fluids for the chemistry, and imaging the hydrate mound, pore fluids from cores, peepers and gas hydrate samples from the mound were as well sampled and analyzed for chemical and isotopic compositions. In order to determine the impact of gas hydrate dissociation and/or methane venting across the seafloor on the ocean and atmosphere, the overlying seawater was sampled and thoroughly analyzed chemically and for methane C isotope ratios. At Bush hill the pore fluid chemistry varies significantly over short distances as well as within some of the specific sites monitored for 440 days, and gas venting is primarily focused. The pore fluid chemistry in the tub-warm and mussel shell fields clearly documented active gas hydrate and authigenic carbonate formation during the monitoring period. The advecting fluid is depleted in sulfate, Ca Mg, and Sr and is rich in methane; at the main vent sites the fluid is methane supersaturated, thus bubble plumes form. The subsurface hydrology exhibits both up-flow and down-flow of fluid at rates that range between 0.5 to 214 cm/yr and 2-162 cm/yr, respectively. The fluid flow system at the mound and background sites are coupled having opposite polarities that oscillate episodically between 14 days to {approx}4 months. Stability calculations suggest that despite bottom water temperature fluctuations, of up to {approx}3 C, the Bush Hill gas hydrate mound is presently stable, as also corroborated by the time-lapse video camera images that did not detect change in the gas hydrate mound. As long as methane (and other hydrocarbon) continues advecting at the observed rates the mound would remain stable. The {_}{sup 13}C-DIC data suggest that crude oil instead of methane serves as the primary electron-donor and metabolic substrate for anaerobic sulfate reduction. The oil-dominated environment at Bush Hill shields some of the methane bubbles from being oxidized both anaerobically in the sediment and aerobically in the water column. Consequently, the methane flux across the seafloor is higher at Bush hill than at non-oil rich seafloor gas hydrate regions, such as at Hydrate Ridge, Cascadia. The methane flux across the ocean/atmosphere interface is as well higher. Modeling the methane flux across this interface at three bubble plumes provides values that range from 180-2000 {_}mol/m{sup 2} day; extrapolating it over the Gulf of Mexico basin utilizing satellite data is in progress.
Download or read book Development of Geophysical Methods to Characterize Methane Hydrate Reservoirs on a Laboratory Scale written by Mike Priegnitz and published by . This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gas hydrates are crystalline solids composed of water and gas molecules. They are stable at elevated pressure and low temperatures. Therefore, natural gas hydrate deposits occur at continental margins, permafrost areas, deep lakes, and deep inland seas. During hydrate formation, the water molecules rearrange to form cavities which host gas molecules. Due to the high pressure during hydrate formation, significant amounts of gas can be stored in hydrate structures. The water-gas ratio hereby can reach up to 1:172 at 0°C and atmospheric pressure. Natural gas hydrates predominantly contain methane. Because methane constitutes both a fuel and a greenhouse gas, gas hydrates are a potential energy resource as well as a potential source for greenhouse gas. This study investigates the physical properties of methane hydrate bearing sediments on a laboratory scale. To do so, an electrical resistivity tomography (ERT) array was developed and mounted in a large reservoir simulator (LARS). For the first time, the ERT array was applied to hydrate saturated sediment samples under controlled temperature, pressure, and hydrate saturation conditions on a laboratory scale. Typically, the pore space of (marine) sediments is filled with electrically well conductive brine. Because hydrates constitute an electrical isolator, significant contrasts regarding the electrical properties of the pore space emerge during hydrate formation and dissociation. Frequent measurements during hydrate formation experiments permit the recordings of the spatial resistivity distribution inside LARS. Those data sets are used as input for a new data processing routine which transfers the spatial resistivity distribution into the spatial distribution of hydrate saturation. Thus, the changes of local hydrate saturation can be monitored with respect to space and time. This study shows that the developed tomography yielded good data quality and resolved even small amounts of hydrate saturation inside the sediment sample. The conversion algorithm transforming the spatial resistivity distribution into local hydrate saturation values yielded the best results using the Archie-var-phi relation. This approach considers the increasing hydrate phase as part of the sediment frame, metaphorically reducing the sample's porosity. In addition, the tomographical measurements showed that fast lab based hydrate formation processes cause small crystallites to form which tend to recrystallize. Furthermore, hydrate dissociation experiments via depressurization were conducted in order to mimic the 2007/2008 Mallik field trial. It was observed that some patterns in gas and water flow could be reproduced, even though some setup related limitations arose. In two additional long-term experiments the feasibility and performance of CO2-CH4 hydrate exchange reactions were studied in LARS. The tomographical system was used to monitor the spatial hydrate distribution during the hydrate formation stage. During the subsequent CO2 injection, the tomographical array allowed to follow the CO2 migration front inside the sediment sample and helped to identify the CO2 breakthrough.
Download or read book In Situ Sampling and Characterization of Naturally Occurring Marine Methane Hydrate Using the D V JOIDES Resolution written by Frank Rack and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The primary accomplishments of the JOI Cooperative Agreement with DOE/NETL in this quarter were that: (1) Frank Rack, Anne Trehu, and Tim Collett presented preliminary results and operational outcomes of ODP Leg 204 at the American Association of Petroleum Geologists annual meeting in Salt Lake City, UT; (2) several Leg 204 scientists participated in special hydrate sessions at the international EGS/AGU/EUG meeting in Nice, France and presented initial science results from the cruise, which included outcomes arising from this cooperative agreement; and, (3) postcruise evaluation of the data, tools and measurement systems that were used during ODP Leg 204 continued in the preparation of deliverables under this agreement. At the EGS/EUG/AGU meeting in Nice, France in April, Leg 204 Co-chiefs Anne Trehu and Gerhard Bohrmann, as well as ODP scientists Charlie Paull, Erwin Suess, and Jim Kennett, participated in a press conference on hydrates. The well-attended press conference entitled ''Gas Hydrates: Free methane found and controversy over the 'hydrate gun''' led to stories in Nature on-line and BBC radio, among others. There were six (6) oral and fifteen (15) poster presentations on ODP Leg 204 hydrate science at the EGS/AGU/EUG Meeting in Nice, France on April 6-11, 2003. This was a very strong showing at a meeting just over six month following the completion of the drilling cruise and highlighted many of the results of the leg, including the results obtained with instruments and equipment funded under this cooperative agreement. At the AAPG annual meeting in Salt Lake City, UT on May 11-14, 2003, Anne Trehu gave an oral presentation about the scientific results of Leg 204, and Frank Rack presented a poster outlining the operational and technical accomplishments. Work continued on analyzing data collected during ODP Leg 204 and preparing reports on the outcomes of Phase 1 projects as well as developing plans for Phase 2.
Download or read book Petrophysical Characterization and Reservoir Simulator for Methane Gas Production from Gulf of Mexico Hydrates written by John Shillinglaw and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Gas hydrates are crystalline, ice-like compounds of gas and water molecules that are formed under certain thermodynamic conditions. Hydrate deposits occur naturally within ocean sediments just below the sea floor at temperatures and pressures existing below about 500 meters water depth. Gas hydrate is also stable in conjunction with the permafrost in the Arctic. Most marine gas hydrate is formed of microbially generated gas. It binds huge amounts of methane into the sediments. Estimates of the amounts of methane sequestered in gas hydrates worldwide are speculative and range from about 100,000 to 270,000,000 trillion cubic feet (modified from Kvenvolden, 1993). Gas hydrate is one of the fossil fuel resources that is yet untapped, but may play a major role in meeting the energy challenge of this century. In this project novel techniques were developed to form and dissociate methane hydrates in porous media, to measure acoustic properties and CT properties during hydrate dissociation in the presence of a porous medium. Hydrate depressurization experiments in cores were simulated with the use of TOUGHFx/HYDRATE simulator. Input/output software was developed to simulate variable pressure boundary condition and improve the ease of use of the simulator. A series of simulations needed to be run to mimic the variable pressure condition at the production well. The experiments can be matched qualitatively by the hydrate simulator. The temperature of the core falls during hydrate dissociation; the temperature drop is higher if the fluid withdrawal rate is higher. The pressure and temperature gradients are small within the core. The sodium iodide concentration affects the dissociation pressure and rate. This procedure and data will be useful in designing future hydrate studies.
Download or read book Development of Geophysical Methods to Characterize Methane Hydrate Reservoirs on a Laboratory Scale written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Gas hydrates are crystalline solids composed of water and gas molecules. They are stable at elevated pressure and low temperatures. Therefore, natural gas hydrate deposits occur at continental margins, permafrost areas, deep lakes, and deep inland seas. During hydrate formation, the water molecules rearrange to form cavities which host gas molecules. Due to the high pressure during hydrate formation, significant amounts of gas can be stored in hydrate structures. The water-gas ratio hereby can reach up to 1:172 at 0°C and atmospheric pressure. Natural gas hydrates predominantly contain methane. Because methane constitutes both a fuel and a greenhouse gas, gas hydrates are a potential energy resource as well as a potential source for greenhouse gas. This study investigates the physical properties of methane hydrate bearing sediments on a laboratory scale. To do so, an electrical resistivity tomography (ERT) array was developed and mounted in a large reservoir simulator (LARS). For the first time, the ERT array was applied to hydrate saturated sediment samples under controlled temperature, pressure, and hydrate saturation conditions on a laboratory scale. Typically, the pore space of (marine) sediments is filled with electrically well conductive brine. Because hydrates constitute an electrical isolator, significant contrasts regarding the electrical properties of the pore space emerge during hydrate formation and dissociation. Frequent measurements during hydrate formation experiments permit the recordings of the spatial resistivity distribution inside LARS. Those data sets are used as input for a new data processing routine which transfers the spatial resistivity distribution into the spatial distribution of hydrate saturation. Thus, the changes of local hydrate saturation can be monitored with respect to space and time. This study shows that the developed tomography yielded good data quality and resolved even small amounts of hydrate saturation inside the sediment sample. The conversion algorithm transforming the spatial resistivity distribution into local hydrate saturation values yielded the best results using the Archie-var-phi relation. This approach considers the increasing hydrate phase as part of the sediment frame, metaphorically reducing the sample's porosity. In addition, the tomographical measurements showed that fast lab based hydrate formation processes cause small crystallites to form which tend to recrystallize. Furthermore, hydrate dissociation experiments via depressurization were conducted in order to mimic the 2007/2008 Mallik field trial. It was observed that some patterns in gas and water flow could be reproduced, even though some setup related limitations arose. In two additional long-term experiments the feasibility and performance of CO2-CH4 hydrate exchange reactions were studied in LARS. The tomographical system was used to monitor the spatial hydrate distribution during the hydrate formation stage. During the subsequent CO2 injection, the tomographical array allowed to follow the CO2 migration front inside the sediment sample and helped to identify the CO2 breakthrough.
Download or read book Quantification of Physical Properties and Dissociation Characteristics for Natural Gas Hydrate Systems written by Yurong Jin and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: With the hydrate development stepping into the field trials, technical challenges and operational concerns arise at the same time including the risk of geological disasters, unstable/discontinuous gas production rates, low energy efficiencies, and high sand influxes. To safely, economically, and efficiently develop a natural gas hydrate (NGH) reservoir in the future, it is of fundamental and practical importance to determine its physical properties, characterize the dynamic attributes along with hydrate extraction, and design and optimize the operational parameters for different dissociation techniques at both laboratory- and field-scales. An equivalent resistance model is proposed and validated to determine hydrate saturation based on the experimentally measured resistivity with consideration of sandstone skeleton, brine salinity, and formation tortuosity. Compared to the classic Archie formula, such an equivalent resistance model shows a better agreement with the experimental measurements and has a less dependence on the accuracy of porosity. Experimental and theoretical techniques have been developed to determine the dissociation front (i.e., the boundary where hydrate saturation is decreased to 0) for hydrate development by combining depressurization and hot brine stimulation. Simulation techniques are employed to determine the decay rate and relative permeability by fitting the experimental measurements and then extended to field applications by applying two different development methods. Two dissociation fronts are found to form separately near the producer and the injector for the combination method. Then, hydrate dissociation behaviour in a brine system by reducing the pressure below the quadruple point is both experimentally and numerically quantified. By approximating the energy contributions, it is found that sensible heat is supplied for hydrate dissociation at the initial stage and that heat conduction from boundary and ice fusion accelerates hydrate dissociation at the final stage. The fluid flow and hydrate dissociation kinetics are found to play a dominant role above the freezing point, while, below the freezing point, the significance of heat conduction from boundary and ice fusion are enhanced during the experiments. Experimentally, sand detachment, migration within matrix, invasion to gravel packing, and production are microscopically observed for openhole gravel-packing with the clayey-silt sediments collected from the Shenhu area of the northern South China Sea. Fractures, wormholes, and fluidized channels are successively developed with a large amount of sand production as well as variations on inlet pressure. Subsequently, the experimental techniques are further modified and improved to eliminate the associated uneven strain-stress effect to microscopically depict sand failure dynamics, sand flow paths, and sand production for wormholes. Theoretically, a wormhole growth model has been proposed to reproduce the sand production for both hydrate-free and hydrate-bearing sandpacks by considering a pressure-gradient-based (PGB) sand failure criterion as well as the porosity and permeability alteration models. The experimental measurements show that a predesigned hydraulic slotting after well completion would decrease the hydraulic gradient near the wellbore and thus decrease the possibility of sand failure. Similar to hydrate production, sand production is also divided into three stages, i.e., before hydrate dissociation, during hydrate dissociation, and after hydrate dissociation.
