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Collaborating Authors
Reservoir Fluid Dynamics
The hydrogeological survey was executed in a small granite island for the construction of underground oil storage caverns. In spite of many cracks and fissures, the permeability of the bedrock was relatively low (10 to 10 cm/sec.) and thus the level of groundwater table was very high. As for the groundwater flow, the authors measured the groundwater pressure in the bore holes and described the potential distribution. The measuring result of environmental tritium concentration in groundwater also supported the existence of the groundwater flow from center to circumference of the island. Furthermore, the potential distribution of groundwater was calculated by the numerical analysis of finite element method using the measured permeability distribution and the estimated rate of recharge from the water balance calculation, and the reasonable groundwater flow enough to account the actual measurement was reproduced. The authors also investigated the environmental influence of the drawdown of groundwater in excavating of the caverns. In case that there exists the relatively permeable layer near the ground surface such as weathered zone of the present study and also that the rate of recharge is relatively large in a humid climate like Japan, the influence of the drawdown by excavation is seemed to be very little. INTRODUCTION The conservation of an oil material in underground caverns using its surrounding groundwater has been carrying out for long period. In this case, the role of groundwater in the bedrock is very important but there is almost no systematic measurement regarding the movement of this groundwater and a number of unclarified problems are still existed. In the bed rock, there exist many cracks and fissures originated from crust diastrophism. The groundwater is stored in them or moves downwards through them by a gravity. Cracks and fissures in the bedrock have very different shapes such as tubular or plate-type, and they cross, expand and connect each other making a very complex structure. Nevertheless from a macroscopic point of view the network of these cracks and fissures compose the storage zone or pervious layer. In case that many irregular and non-homogeneous fissures exist in the bedrock and make a network of fissures, it may be reasonable to consider this bedrock hydraulically homogeneous. As for the groundwater flow in isotropy and homogeneous media, Hubbert (1940) solved the groundwater flow analytically. After then, Toth (1962) and Freeze and his co-workers (1967) tried to estimate the flow in the more complex pervious layer using computer simulation. However, the actual measurement of the groundwater flow was observed only that by Meyboom (1966) in an aluvium deposit, and the groundwater flow in the bedrock has not been measured by now. The purpose of the present study is to understand the regime of the groundwater in the bedrock by the actual measurement and mathematical modeling, and also to estimate the influence on the environment by excavation. In the present study, the authors investigated the flow characteristics of the groundwater in bedrock using the potential distribution measured by double packered groundwater pressure measuring apparatus, and the concentration of environmental tritium containing in the groundwater. study is shown in Fig. 1.
- Geology > Geological Subdiscipline (0.69)
- Geology > Rock Type > Igneous Rock > Granite (0.62)
- Reservoir Description and Dynamics > Reservoir Fluid Dynamics > Flow in porous media (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization (1.00)
- Data Science & Engineering Analytics > Information Management and Systems (0.84)
Study On Seepage Flow Through Rock Mass Surrounding Caverns For Petroleum Storage
Komada, H. (Central Research Institute of Electric Power Industry) | Nakagawa, K. (Central Research Institute of Electric Power Industry) | Kitahara, Y. (Central Research Institute of Electric Power Industry) | Hayashi, M. (Central Research Institute of Electric Power Industry)
In unlined underground rock caverns, liquid petroleum and petroleum gas can be stored by making use of natural or artificial ground water pressure. In case of applying the unlined underground storage caverns to the cracky rock mass, it seems to be most important that the behaviour of the ground water through the rock mass surrounding the caverns is studied in advance. This study, therefore, discusses the following subjects concerning unlined underground oil storage caverns.The numerical study on the effects of natural ground water pressure on the storage caverns. The numerical study on the effects of artificial ground water pressure on the storage caverns. Model experiment about gas leakage into the crack of rock mass. INTRODUCTION Unlined underground storage system of petroleum has been proven to be efficient in the effective exploitation, environmental preservation, safety and economy. The system has already many past references in Europe and America. However, in case when the said system is adopted to the cracky rock mass, it is necessary to study and examine the nature of the rocks, the structure of fuel storage tank and the influence over the environment. This report is intended to describe the results of the analysis and experiments on the seepage flow made in relation to the matters most important for the construction of the unlined underground storage tank for petroleum, that is to say, the water pressure required for preventing leakage of oil and gas, the lowered level of ground water liable to give influence over the environment, and the water leakage volume indispensable for determining the capacity and the economy of the equipments and apparatuses to be involved. NUMERICAL STUDY ON THE EFFECT OF NATURAL GROUND WATER PRESSURE ON THE STORAGE CAVERNS The petroleum like heavy oil and light oil having low vapor pressure can be stored under the atmospheric pressure when the underground caverns are not found in the state completely covered with ground water. This is to say, there happens no gas leakage and no oil leakage even if the ground water level reaches the cavern. On the other hand, when the underground caverns are excavated in the rock mass beneath the natural ground water level, the seepage flow into the caverns through the surrounding rock mass will be happened. Consequently, it is worried that the ground water level on the upper part of the caverns will fall down after the excavation of the cavern. Therefore, it is necessary to understand the behaviour of natural ground water around the cavern in case when heavy oil, light oil, etc. are to be stored under natural ground water only. In this chapter the behaviour of ground water around the cavern will be analyzed through two dimensional analysis of seepage flow in saturated-unsaturated porous media (Komada, 1978) and the possibility of unlined underground storage under natural ground water only will be examined.
- Reservoir Description and Dynamics > Storage Reservoir Engineering > Natural gas storage (1.00)
- Reservoir Description and Dynamics > Reservoir Fluid Dynamics > Flow in porous media (1.00)
- Facilities Design, Construction and Operation > Natural Gas Conversion and Storage > Liquified natural gas (LNG) (0.87)
The field testing requirements of nuclide transport models are changing The existing methods of measuring hydraulic conductivity in-situ are reviewed and their relevance to modelling requirements assessed. Within the field of multiple borehole methods, some techniques, suitably adapted from the original oilfield environment, are suggested. The limited methods available to carry out three dimensional testing are supplemented with a new method based on propagating a sinusoidal pressure pulse. The distances over which testing could be accomplished are assessed together with the range of the rock parameters within which the test is practical It is concluded that the new method has interesting possibilities and could provide a series of hydraulic diffusivity vectors. INTRODUCTION The last ten years have seen the increasing use of computer models and techniques within hydrogeology in general, and solute transport investigations in particular. The nuclide transport models produced so far are still in their infancy but show a trend towards increasing complexity which is likely to continue. The tendency is to add more and more effects, such as thermally induced flows, radioactive decay and rock stress effects, onto the basic groundwater flow model. As yet most groundwater flow models are of the porous medium type and assume that Darcys law broadly applies within the scale of interest. Some work though, has been carried out on a model involving flow through a system of blocks bounded by shear zones, and the results (Axelsson and Carlsson, 1979) differ considerably from the homogenous case (Stokes, 1979). Whatever the particular type of model involved, all require field measurements of those factors which delimit the velocity and direction of groundwater movements within quite large volumes of rock. In the simpler models, where groundwater is assumed to flow horizontally in response to a regional hydraulic gradient, equivalent to the average dip of a water table, the field measurements required are straight forward. However, as the models become more complex, the requirements on field investigations become more exacting and, although the basic hydrogeological parameters of hydraulic conductivity, hydraulic potential, porosity and dispersivity are still relevant, the nature of their variation is coming under closer scrutiny. It is the intention here to examine the changing methods relating to the field measurements of hydraulic conductivity in fractured crystalline rocks and their likely relevance. EXISTING SINGLE BOREHOLE TECHNIQUES Average values of hydraulic conductivity are the usual basis of most porous medium models and can be obtained by either injecting or abstracting water from a completely open borehole. In an attempt to measure the variation of hydraulic conductivity with depth, straddle packer systems are currently being employed by many investigators (e.g. Davison, 1980, BRGM, 1979 and Carlsson,1979). These packer results tend to apply to individual fractures near the borehole, and only by averaging large numbers of results, is it possible to infer a depth-dependent permeability relationship. The use of short spacing straddle packer measurements does mean however, that the spatial variability of hydraulic conductivity can be deduced.
- Reservoir Description and Dynamics > Reservoir Fluid Dynamics > Flow in porous media (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization (1.00)
Thermal Effects On Groundwater Flow Around A Radioactive Waste Depository In Hard Rock
Robinson, P.C. (Atomic Energy Research Establishment, Harwell, Oxfordshire, UK) | Hodgkinson, D.P. (Atomic Energy Research Establishment, Harwell, Oxfordshire, UK) | Rae, J. (Atomic Energy Research Establishment, Harwell, Oxfordshire, UK)
The heat output from high level radioactive waste buried in hard rock can give rise to groundwater convection currents. These flows can change the natural groundwater flows for thousands of years after the decommissioning and sealing of a depository. This paper presents the results of some recent calculations of this effect and discusses the possible consequences for water-borne leakage of radionuclides back to the biosphere. INTRODUCTION One of the proposed options for disposing of radioactive waste from the nuclear power industry is to bury it in depositories deep in hard rock (KBS. 1977; Roberts. 1979). The heat generated by the decaying radionuclides in high level waste would be dissipated largely by thermal conduction using the rock mass as a heat sink. For a depository' containing a three-dimensional array of waste canisters, the resulting temperature field would extend several hundred meters into the rock, and rise and fall on a timescale of centuries (Beale, Bourke and Hodgkinson. 1979). The most likely way in which radioactivity could reach Man from such a depository is by groundwater leaching radionuclides from the waste and transporting them to the biosphere. This leakage path is inhibited by a number of in-series barriers including the high leach resistance of the waste form. its containment in a corrosion resistant canister and the impermeability and absorptivity of the rock mass (Hill and Grimwood. 1978). This paper addresses one aspect of this problem namely the perturbation of the existing groundwater flow paths by buoyancy flows driven by the above temperatures. NATURAL GROUNDWATER FLOW A vertical section through a hypothetical region, is used to illustrate the hydrogeological effects of a high level waste depository on its surroundings. The rock mass is treated as a porous medium with constant values of permeability (10m) and flowing porosity (10) chosen to be representative of those measured in fractured hard rock masses (Axelsson and Carlsson. 1979; Davison. 1979; Lundstrom and Stille. 1978). It is assumed that precipitation far exceeds the infiltration into this low permeability rock mass so that the water table is always coincident with the land surface which therefore acts as a constant pressure boundary. THERMAL EFFECTS The temperature field around a depository will cause water in the fractures of the rock to rise because of buoyancy effects. Such upward flows are of concern because they could shorten the time taken by radionuclides, leached from the waste, to reach the surface. Temperature profiles along the vertical centreline of a depository are shown. The temperature rise near the centre of the depository reaches a maximum of 6l °C after about a century and then slowly decays as heat is distributed over an ever increasing volume of rock. However, the total amount of heat contained in the rock mass has not started to decay at the times shown. This heat energy has the potential to cause buoyancy flows long after the temperature rise at the centre of the depository has fallen to a fraction of its maximum value.
- Water & Waste Management (1.00)
- Energy > Power Industry > Utilities > Nuclear (1.00)
- Reservoir Description and Dynamics > Reservoir Fluid Dynamics > Flow in porous media (1.00)
- Health, Safety, Environment & Sustainability > Environment > Naturally occurring radioactive materials (1.00)
Ground water flow through an underground repository for nuclear waste located 500 m below the ground surface as proposed by Swedish authorities may be considerably reduced by surrounding the repository with a zone of constant potential like Faraday's cage in electricity. The zone consists of tunnels and boreholes between them. INTRODUCTION It is proposed that nuclear waste from Swedish power plants be permanently stored in an underground repository. This should consist of a system of storage tunnels located 500 metres below the ground surface; and the nuclear waste should be enclosed in special canisters surrounded by compacted bentonite. The canisters are calculated to last for many thousands of years. However, if the canisters should be destroyed, radioactive material would be transported with groundwater to the biosphere in wells, rivers and lakes, or the sea. Therefore, the requirement is that the rock as the last barrier should have such very low permeability that the movement of the groundwater should take many hundreds or thousands of years from the storage to the biosphere. The Swedish Government has approved this project and accepted the judgement by the State Nuclear Power Safety Board that acceptable rock for a storage of nuclear waste is available. However, many people have protested against this decision, and different opinions exist about rock quality and the long-term effect of the storage. HYDRAULIC CAGE In primary rock such as granite etc. there exist small micro-cracks along mineral particles. Therefore, it is true that groundwater flow will occur in such rock but only to a very small extent. The permeability of such as homogeneous considered rock is very low, in fact so low that the rock can be considered to be impervious, and that the ground water flows in open cracks only. If the cracks are distributed evenly in different directions and the distance between the cracks is not too great, we may calculate the groundwater flow by using Darcy''s formula:q = k.S m/s per m area (1) where k = coefficient of permeability, m/sS = hydraulic gradient, m/m The velocity of the water in the system of cracks isv = q/n = 1/n. k. s m/s (2) where n = effective porosity. The effective porosity is not equal to the total porosity of the rock. The porosity of. the "homogeneous" rock should not be included, and neither cracks running laterally to the direction of the groundwater flow. The porosity, n, is difficult to determine at the site, but may be assumed to be between 0.001 and 0.0001 for very good hard rock. The formulae show that the intensity of the groundwater flow is proportional to the hydraulic gradient. A method to reduce the groundwater flow and its velocity and thereby to reduce the requirement regarding the permeability of the rock is to reduce the hydraulic graient around the repository.
- Reservoir Description and Dynamics > Reservoir Fluid Dynamics > Flow in porous media (1.00)
- Reservoir Description and Dynamics > Formation Evaluation & Management (1.00)
Mining Technology Development For Hard Rock Excavation
Hustrulid, W. (Colorado School of Mines) | Cudnick, R. (Battelle Memorial Insititute) | Trent, R. (Colorado School of Mines) | Holmberg, R. (SveDeFo) | Sperry, P.E. (Woodland Hills) | Hutchinson, R. (Colorado School of Mines) | Rosasco, P. (Colorado School of Mines)
A research facility has been established in the granitic gneiss of the CSM Experimental Mine at Idaho Springs, Colorado, for the purpose of evaluating/ developing mining, geologic and geotechnical procedures appropriate for use in establishing nuclear waste repositories in hard rock. An experimental room has been excavated using careful blasting procedures. The extent and magnitude of blast damage is being evaluated. Structural geology is being mapped to assess continuity. INTRODUCTION The Colorado School of Mines under sponsorship of the Department of Energy through the Office of Nuclear Waste Isolation has established a hard rock research facility at its Experimental Mine near Idaho Springs, Colorado. This facility which is located in the Idaho Springs formation (a granitic gneiss) is presently being used for the following purposes:evaluate and develop techniques for careful excavation in hard rock. develop the mapping techniques required for adequately describing the structural geology. evaluate the structural continuity in granitic gneiss. evaluate the structural damage done to the rock mass by blasting. develop techniques for evaluating fracture permeability. evaluate the permeability changes in the rock mass due to blasting. Although specifically oriented towards nuclear waste storage/disposal, the techniques and procedures being developed/evaluated have wide applicability to all underground excavations in hard rock. THE CSM EXPERIMENTAL MINE The Edgar Mine (the proper name for the CSM Experimental Mine) is located at an elevation of about 2,30Om at Idaho Springs, Colorado, approximately 40km from the CSM campus at Golden. Geologically, the mine is located in an area which has been varyingly affected by seven tectonic and/or structural events dating back 1.750 b.y. Three of the seven events appear to have played a dominant role in establishing the structural trends present. The Boulder Creek Orogeny (1.750–1.690 b.y.) initially resulted in regional dynamothermal metamorphism of the Precambrian basement rocks and formed a structural trend still existent today. A younger, un-named Precambrian deformation (1.30 b.y.) was dominantly cataclastic accompanied by minor and local recrystallization and folding. A third event during the Late Cretaceous to Early Tertiary time (70–40 m.y.) not only resulted in an undetermined amount of reopening of Precambrian, age fracture sets but also was responsible for superposition of a younger set of fractures on a regional basis throughout the Precambrian basement rocks. The younger Precambrian cataclastic event and the Late Cretaceous-Early Tertiary Laramide Orogeny resulted in the rocks of the central Colorado Front Range having undergone brittle failure. The ores for which the Edgar was developed are thought to have been deposited at that time. The Edgar Mine was named after the Edgar vein which strikes N65°E on the average and dips 70–85 N.W. It consisted of a crushed wall rock, primarily a schist of the Idaho Springs Formation, from a few inches to three feet in width. It was slightly silcified and contained disseminated pyrite. Records from the 1870's revealed that the first class ores of the Edgar Mine averaged 16 gms/t gold, 151 gms/t silver and seldom less than 45 to 50 percent lead.
- North America > United States > Idaho (1.00)
- North America > United States > Colorado (1.00)
- Geology > Rock Type > Metamorphic Rock > Gneiss (0.65)
- Geology > Structural Geology > Tectonics > Plate Tectonics (0.44)
- Geology > Structural Geology > Tectonics > Compressional Tectonics > Fold and Thrust Belt (0.44)
- Materials > Metals & Mining (1.00)
- Energy > Oil & Gas > Upstream (1.00)
- Energy > Power Industry > Utilities > Nuclear (0.96)
- Reservoir Description and Dynamics > Reservoir Characterization (1.00)
- Reservoir Description and Dynamics > Reservoir Fluid Dynamics > Flow in porous media (0.58)
- Data Science & Engineering Analytics > Information Management and Systems > Data mining (0.51)
The Stripa mine test site, located approximately 200 km west-northwest of Stockholm, Sweden, is the focal point of a detailed fracture-hydrology study. Preliminary results from three of the five main components of this program are discussed in this paper. These three components are a detailed borehole testing program to determine the directional permeabilities of the fractured granite, a macro permeability experiment - an attempt to measure the average permeability of a large volume of the fractured granite, and a detailed study of the groundwater geochemistry to determine the origin and age of the groundwater both in and around the immediate mine area. Preliminary analysis of the borehole tests gave equivalent porous media hydraulic conductivities that ranged from 10 to 10 cm/sec. Preliminary results from the macro permeability experiment suggests bulk rock mass hydraulic conductivities of about 10–9cm/sec. Environmental isotope and chemical analysis of waters collected from water bearing fractures in the granite show that the groundwaters are many thousands of years old and their salinity increases with depth. It is not yet clear whether the deep groundwaters (>338m) belong to local or regional flow systems. INTRODUCTION Fractured crystalline and argillaceous rocks have been proposed as alternative host rocks for storage or disposal of high-level radioactive waste. To evaluate this proposal, one must obtain an accurate description of the hydrology of fractured rocks. Thus, one must begin to develop data bases that permit one to answer questions such as: what is the role of fractures in determining the nature (isotropic or anisotropic) of fractured rock permeability? and under what conditions, if any, can fractured rock masses be treated as porous media or equivalent porous media? The first question dictates that we must develop methods of characterizing a fracture system and its role in determining the hydrology of fracture systems in order to provide a framework within which to interpret local and large scale flow systems in fractured rock masses. Answers to the second question determine the type of borehole testing programs that will be undertaken in concept verification studies. Borehole testing programs must provide the data needed to develop hydraulic parameters that clearly describe how fluids move and the rate at which they move through fractured rocks. based on porous media concepts will not provide sufficient data if, as is permeability of fractured rocks is highly anisotropic. Borehole testing programs generally agreed, the The volumes and rates of groundwater movement through fractured rock masses, predicted from borehole tests, must be supported by data obtained from other field studies. Such supporting data can be obtained from large-scale tunnel or shaft pumping tests, that perturb a volume of the rock mass many times larger than that tested by a single borehole, and through detailed studies. of the geochemistry and isotopic composition of the groundwaters. Groundwater flow systems configuration, calculated from measured distributions of permeabilities, porosities and hydraulic head boundary conditions, must be consistent with data of the evolution of groundwater geochemistry in fractured rocks and the distribution of ages inferred from isotope analysis.
- Europe > Sweden (0.68)
- North America > United States > California > Alameda County > Berkeley (0.47)
- Geology > Geological Subdiscipline > Geochemistry (1.00)
- Geology > Rock Type > Igneous Rock > Granite (0.67)
- Geology > Geological Subdiscipline > Environmental Geology > Hydrogeology (0.64)
A preliminary study is presented for final storage for low- and medium-level waste in crystalline rock at shallow depth. The study deals with a suitable transport- and handling system for waste packages, design of three different types of rock cavities and varying manmade barriers, the activity dispersion through the man-made barriers, dilution conditions in the groundwater and doses to individual and mankind. The study shows that large rock vaults will give the lowest costs and the doses to individual and mankind is far below the natural radiation. BACKGROUND Over the past few years, considerable efforts have been devoted to solving the question of how the high-level waste is to be finally disposed of with adequate safety. The problem of disposal (final storage) of the low-level waste has only been dealt with cursorily. It is true that similar problems exist for both types of waste, but there are nonetheless a number of important differences. For many reasons, which we cannot go into here, it is best if the high-level waste is not placed in terminal storage for another 30–40 years. In the interim, the waste will be stored in CLAB (central temporary storage facility for spent fuel), which is to be built in Oskarshamn. As far as the low-level waste is concerned, existing storage facilities will have to be expanded within the near future. The temporary storage facilities located at the nuclear power stations are normally designed to accommodate the waste from 5 or, at the most 10 years of production. Since additional storage facilities have to be built anyway, it would be clearly advantageous if they could be designed to function as final storage facilities in the future as well. This would also permit valuable experience to be gained for the storage of the more complicated high-level waste later on. The amount of low-level waste is many times greater than the amount of high-level waste. For this reason, even though the demands on the storage premises are considerably lower, great economic gains can be made by an earlier final storage of the low-level waste. The National Council for Radioactive Waste (PRAV) has therefore been studying the transportation and final storage of the low-level waste for 2 1/2 years now. The risks of dispersal 1n nature have also been studied, and the ~of adverse impact on biological life have been assessed. The goal has been to have a final repository finished by the time the temporary storage facilities at the nuclear power stations are filled (1986–88), but this would now appear to be impossible. It will probably be necessary to expand the temporary storage facilities to accommodate an additional 2 years of production at most nuclear power stations. The geological conditions necessary for an underground final repository in Sweden exist only in crystalline rock. There are small formations of sediment in some parts of the country, but these formations are generally relatively near the surface and situated in areas of high population density, and are therefore judged to be less suitable for the location of a final repository for the waste.
- Europe > Sweden (0.72)
- Europe > Norway > Norwegian Sea (0.24)
- Reservoir Description and Dynamics > Reservoir Fluid Dynamics (0.47)
- Health, Safety, Environment & Sustainability > Environment > Naturally occurring radioactive materials (0.35)
- Health, Safety, Environment & Sustainability > Environment > Waste management (0.35)
An almost spherical rock cavern is surrounded at some distance by a fairly thick clay barrier. Nuclear waste canisters are mounted in cylindrical holes traversing large concrete balls. These are stored in the cavern together with similar concrete balls filling up the entire cavern space. The clay barrier prevents ground water circulation for a very long time, enhances ion-exchange, and increases the repository resistance against future tectonic movements and earthquakes. Calculations of heat balance, thermal effects, clay barrier function and costs have been performed. One repository (Fig. 1) accommodates one year's unreprocessed waste from 12 nuclear 1000 MWe reactors assuming 10 years of interim storage. Construction operations are outlined. Various advantages of the concept are emphasized (see list at end of paper). INTRODUCTION The WP-CAVE concept was first published in the ROCKSTORE 77 Proceedings (Akesson and Hök, 1977). From that on the concept has been developed through theoretical calculations and feasibility studies. The present state of the project is given in a fairly comprehensive report which is available (Akesson, Bergman and Sagefors, 1979). GENERAL DESCRIPTIONS An overall-view of a WP-CAVE repository is given in Fig. 1. As shown in Fig. 2., the storage cavern proper is almost spherical and has a cylindrical heat stack placed in its centre. The space around the stack is filled with porous concrete balls (Fig. 2). The waste canisters to be stored are porously mounted in large concrete balls (Fig. 2). The balls loaded with the waste are lowered into the cavern through the shaft (Fig. 1) and placed in the bottom half of the stack (Fig. 2). The upper half of the stack is filled with empty balls. The shaft can then be plugged and sealed (no ventilation is needed). Without any monitoring from the outside the sealed and abandoned cavern will remain dry and porous for more than 1000 years. Natural convection through the stack and the ball filling (Fig. 2) will transport the heat released from the loaded balls (dotted in Fig. 2) to the cavern wall. The stack and the balls are designed to stay substantially intact for the first 100-200 years. If desired the loaded balls can during this period of time be hoisted through the shaft (the seal first having been broken) and the stored waste retrieved. After these first 100-200 years the heating power of the stored waste will have decreased to only a few percent of its starting value and there will be no further need for the (convective mechanism. A gradual collapse of the balls, the stack and the cavern wall will then do no harm and can be accepted. The excavation of the slot for the barrier will start from below (Fig. 1) and the slot will successively be filled with a compacted compound of sodium bentonite and quartz sand. This compound tends to expand when absorbing water and will therefore gradually develop a strong pressure against the slot walls. The clay barrier will thus remain continuous and tight for a very long time.
- Geology > Mineral > Silicate (1.00)
- Geology > Rock Type (0.94)
- Geology > Geological Subdiscipline (0.93)
- Geology > Structural Geology > Tectonics > Plate Tectonics > Earthquake (0.54)
- Water & Waste Management > Solid Waste Management (1.00)
- Energy > Power Industry > Utilities > Nuclear (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Reservoir geomechanics (0.46)
- Reservoir Description and Dynamics > Reservoir Fluid Dynamics > Flow in porous media (0.46)
The disparity between energy production and demand has led to increased research into the use of aquifers for the long-term, large-scale storage of thermal energy. Currently, there are several field experiments and feasibility studies under way in which the technical, economic, and environmental aspects of aquifer storage are being researched. The present paper surveys the recent theoretical efforts in aquifer storage research and the impact their results may have on these field projects. Major work is highlighted according to three categories: semianalytic studies, numerical modeling studies, and site-specific studies. INTRODUCTION The need for energy storage arises from the disparity between energy production and demand. The development of viable storage methods will play a significant role in our ability to implement alternative energy technologies and use what is now waste heat. The ability to provide heat at night and during inclement weather is a key factor in the development of solar energy. Conversely, winter cold, in the form of melted snow or water cooled to winter air temperatures, can be used as a coolant or for air-conditioning. Practical storage systems would also allow us to capture the heat that occurs as a by-product of industrial processes and power production. Industrial plants and electric utilities generate tremendous amounts of waste heat, which is usually dissipated through an expensive network of cooling towers or ponds to avoid thermal pollution. Because periods of heat demand do not generally coincide with electricity generation or industrial production, a viable storage method is essential if this heat is to be used. Such a method would not only provide for the use of what is now waste heat, but would significantly decrease the necessary investment in cooling and backup heating systems. In recent years, aquifers have been studied as a very promising means for the long-term, large-scale storage of thermal energy. Aquifers are porous underground formations which contain and conduct water. Confined aquifers are bounded above and below by impermeable clay layers and are saturated by water under pressure. They are physically well suited to thermal energy storage because of their low heat conductivities, large volumetric capacities (on the order of 109m), and their ability to contain water under high pressures. Aquifers are also attractive storage sites because of their widespread availability. Aquifer storage is not a new concept. Over the last few decades aquifers have been used to store fresh water, oil products, natural gas, and liquid wastes. However, it has only been in recent years that their use for thermal energy has been suggested. Initial studies were conducted by Rabbimov, Umarov, and Zakhidov (1971), Meyer and Todd (1972), Kazmann (1971), and Hausz (1974). A good source of information about more recent work is the proceedings of the Thermal Energy Storage in Aquifers Workshop (Berkeley, 1978). Current research and development activities are reviewed in the quarterly ATES Newsletter prepared by Lawrence Berkeley Laboratory. Recent work includes field experiments at Mobile, Alabama (USA), Gaud (Fance), Bonnaud (France), College Station (USA).
- Europe (1.00)
- North America > United States > Alabama > Mobile County > Mobile (0.24)
- North America > United States > Gulf of Mexico > Central GOM (0.16)
- Energy > Renewable > Geothermal (1.00)
- Energy > Oil & Gas > Upstream (1.00)
- Energy > Energy Storage (1.00)
- North America > United States > West Virginia > Auburn Field (0.99)
- North America > Canada > Alberta > French Field > Arl French 16-26-64-1 Well (0.99)
- Europe > Russia > Northwestern Federal District > Komi Republic > Timan-Pechora Basin > Pechora-Kolva Basin > Usa Field (0.89)
- Reservoir Description and Dynamics > Reservoir Fluid Dynamics (1.00)
- Reservoir Description and Dynamics > Improved and Enhanced Recovery (1.00)
- Production and Well Operations > Well & Reservoir Surveillance and Monitoring (1.00)
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