Salt Cavern Storage Research Articles

Developments in Researches on the Disasters during Cavern Construction in Salt Beds with Multi-Interlayer

This study analyses the developments in researches on the disasters during cavern construction in salt beds with multi-interlayer. Relative to the foreign large salt dome landscape, there are many layers of mudstone in salt beds which has a thin single layer. And such special geological conditions increase the difficulty of solution mining in the control of cavity shape and stability of the cavity, which easily leads to disasters. To statistical analysis the disasters in process of cavern building with multi-interlayer in china, it show that: taking Chinese geological conditions for example, the disasters during cavern construction in salt beds with multi-interlayer caused the failure of cavity can be divided into three categories: geological conditions in beds; the damage of cavity wall in the process of cavity building; the distortion of cavity shape expansion. To analyze predisposing factors lead to salt cavern storage failure in detail, the mechanism of the corresponding factors lead to disaster has been summarized. Finally , some suggestions has been proposed to avoid the disaster maybe happened.

Stability Analysis of Storage Caverns in Bedded Salt Rock Formation

Salt cavern storage is usually in bedded salt rock formation except salt dome, in particular in China. The rocks composing a bedded salt rock formation, e.g., mudstone, rock salt, interlayer, etc., often present viscoelastic-plastic behaviors, which is an important influencing factor of the long-term stability of salt caverns in it. Modelling the rheological behavior with the Druck-Prager creep model, an example of stability analysis of four salt caverns at Jintan Salt Mine of China with the finite element method is elaborated in this paper. The results show that besides the inevitable loss of effective storage room with time due to creep deformation, which decreases evidently with internal pressure but decreases slowly at a certain pressure value, the variation of operating internal pressure in each cavern can cause the change of volumes of other nearby caverns and then affect the stability of all the caverns. The internal pressure difference should be as small as possible during the operation of salt caverns.

Large-scale hydrogen energy storage in salt caverns

Large-scale energy storage methods can be used to meet energy demand fluctuations and to integrate electricity generation from intermittent renewable wind and solar energy farms into power grids. Pumped hydropower energy storage method is significantly used for grid electricity storage requirements. Alternatives are underground storage of compressed air and hydrogen gas in suitable geological formations. Underground storage of natural gas is widely used to meet both base and peak load demands of gas grids. Salt caverns for natural gas storage can also be suitable for underground compressed hydrogen gas energy storage. In this paper, large quantities underground gas storage methods and design aspects of salt caverns are investigated. A pre-evaluation is made for a salt cavern gas storage field in Turkey. It is concluded that a system of solar-hydrogen and natural gas can be utilised to meet future large-scale energy storage requirements.

Numerical Study of the Influence of Interlayer Mechanical Properties on Salt Cavern Storage Stability

Numerical and experimental studies including different soft and hard layer thickness were conducted under different pressures for analyzing the effect of interlayers on stability of salt cavern considering shrinkage rate, plastic zone and displacement vectors. The results indicate that: Cavern shrinkage rate is increased appreciably with increased of soft layer thickness and decreased significantly with increased of hard layer thickness. The plastic zone change is not obviously with increased of soft layer thickness but obviously with hard layer and plastic zone are significant differences at layer while cavern including soft layer and hard layer, the soft layer effect on plastic zone is less than hard layer and it is more sensitive to pressure increasing, the fracture of hard layer is more easily than soft layer. Maximum displacements happen at layer while cavern including soft layer and at salt rock while cavern including hard layer. Comprehensive differences effects of soft layer and hard layer to stability of salt cavern storage find that fine hard layer and heavy soft layer are more unfavorable. The results are important to oil-gas storage cavern modeling analysis in laminated salt rock.

Study on tri-axial creep experiment and constitutive relation of different rock salt

To evaluate the effect of the long-term operation of a salt cavern in a given construction on rock deformation and its stability, tri-axial creep tests to the glauberite, anhydrite, and argillaceous rock salt are conducted, from which the creep curves as well as exponential functions of strain rate during the steady creep stage and creep constitutive equations of different rock salt in the experimental process derived are obtained. The study results show that: (i) Under the same deviatoric stress, the strain rate of argillaceous rock salt is lower than the glauberite and anhydrite, and the difference becomes larger with the increase of the deviatoric stress; (ii) The creep constitutive equations of different kinds of rock salt are in good agreement with the Burgers model, besides which the respective characteristics of these two creep models are compared. The change of creep parameters also illustrates the discrepancy of rock salt. The researching results can provide some references for long-term stability analysis of gas storage in salt caverns.

A Review of Fatigue Crack Growth for Pipeline Steels Exposed to Hydrogen.

Hydrogen pipeline systems offer an economical means of storing and transporting energy in the form of hydrogen gas. Pipelines can be used to transport hydrogen that has been generated at solar and wind farms to and from salt cavern storage locations. In addition, pipeline transportation systems will be essential before widespread hydrogen fuel cell vehicle technology becomes a reality. Since hydrogen pipeline use is expected to grow, the mechanical integrity of these pipelines will need to be validated under the presence of pressurized hydrogen. This paper focuses on a review of the fatigue crack growth response of pipeline steels when exposed to gaseous hydrogen environments. Because of defect-tolerant design principles in pipeline structures, it is essential that designers consider hydrogen-assisted fatigue crack growth behavior in these applications.

Natural gas storage valuation and optimization: A real options application

AbstractIn this article, we present an algorithm for the valuation and optimal operation of natural gas storage facilities. Real options theory is used to derive nonlinear partial‐integro‐differential equations (PIDEs), the solution of which give both valuation and optimal operating strategies for these facilities. The equations are designed to incorporate a wide class of spot price models that can exhibit the same time‐dependent, mean‐reverting dynamics, and price spikes as those observed in most energy markets. Particular attention is paid to the operational characteristics of real storage units. These characteristics include working gas capacities, variable deliverability and injection rates, and cycling limitations. We illustrate the model with a numerical example of a salt cavern storage facility that clearly shows how a gas storage facility is like a financial straddle with both put and call properties. Depending on the amount of gas in storage the relative influence of the put and call components vary. © 2009 Wiley Periodicals, Inc. Naval Research Logistics 2009

New procedure for tightness tests (MIT) of salt cavern storage wells: Continuous high accuracy determination of relevant parameters, without the need to use radioactive tools

Abstract In performing the mechanical integrity test (MIT) on salt cavern storage wells the most used method worldwide is the In-Situ Balance method (ISB). The principal sources of errors in the execution and evaluation of the test are the depth change of the gas/liquid interface and the surface area of the interface. In the past, the interface depth has been predominantly determined using radioactive methods, i.e. gamma-gamma, neutron-gamma and neutron-neutron tools. The disadvantages of these methods are the low measurement accuracy and the need to perform several tool runs during the test period, which introduces an additional source of error, because cost factors normally prevent continuous measurements. A new method (SoMIT) is presented based on ultrasonic techniques in which the interface depth, the temperature and the differential pressure at the interface depth can be measured continuously during the tightness test while achieving much greater levels of accuracy than was previously the case. In the SoMIT method a tool is fixed in place throughout the entire test period such that the problems associated with several tool runs are also avoided. The advantages for users are to be found in the greater accuracy available to verify the tightness of the well and also in the reduced test period.

Gas Storage and Operations in Single-Bedded Salt Caverns: Stability Analyses

Summary Bedded salt formations are located throughout the U.S., providing valuable storage capacity for natural gas and other hydrocarbons. To increase gas-storage capabilities and provide operators with improved geotechnical design and operating guidelines for these caverns, stability analyses of single-bedded salt caverns have been completed and are described in this paper. This work is a part of integrated efforts initiated and sponsored by the U.S. Department of Energy (DOE), the Gas Technology Institute (GTI), and Pipeline Research Council International, Inc. Numerical geomechanical models have been developed to investigate single-cavern deformation and bedding-plane slip for a variety of cavern configurations. A viscoplastic salt model has been developed based on an empirical creep law developed for the Waste Isolation Pilot Plant (WIPP) Program and combined with a Drucker-Prager model for damage and failure. The nonsalt materials are described with either a traditional Mohr-Coulomb model, or an elastic model, depending on layer properties. A baseline model with specified geometric dimensions is first selected and subjected to 1-year cyclic pressure operations. The amount of damage around the cavern wall and roof is evaluated and used as a comparison in the study. Then, the operations are extended to 15 years to study cavern stability for long-term gas storage and operations. In addition to the baseline model, parametric studies have been performed to investigate cavern damage as a function of salt roof thickness, overburden stiffness, interface properties, and cavern geometries. Each cavern simulation includes 1 year of pressure cycling with a minimum, mean, and maximum cavern pressure of 6.1 MPa (884.5 psi), 8.8 MPa (1,276 psi) and 14.9 MPa (2,160.5 psi), respectively. Different operation conditions (e.g., hydrostatic, cyclic, and direct-pressure drawdown) are compared and evaluated in terms of cavern stability. These analyses can be a basis to selecting the best salt cavern candidate for gas storage and operations as well as helping to assess critical cavern design parameters for thin-bedded salt formations.

Performance Prediction of Underground Gas Storage in Salt Caverns

Underground gas storage is a common activity in countries with major transport and distribution gas pipeline infrastructures, which allows to efficiently resolve demand seasonality problems. Subsurface caverns in salt formations are being increasingly used for storage of natural gas. In this study, a real salt cavern having the potential for being an underground gas storage unit was evaluated. A model of the salt cavern was constructed within the gas simulator established for the purposes of this study. The simulator IMEX that is CMG's (Computer Modelling Group) new generation adaptive implicit explicit simulator was used to investigate the production and injection performance and depth of caverns. Grid description of the salt cavern was used. Theoretically a cylindrical prism was chosen for modelling of the salt cavern. The production and injection well was set in the middle of the salt cavern. The place of the salt cavern was chosen in Tuz Gölü field in central Turkey. The data of this field and old wells were reviewed. In calculations, the actual data of the field was used. The data includes formation and salt characteristics (densities, limiting stress of salt, temperature). The selection of the cavern depth is one of the most critical points. The depth determines the cavern pressure. Six depth intervals were chosen for the top level of cavern. From various selected depths, the depth of the cavern was optimized and found as 1,275 m. It was seen that as depth increased maximum cavern pressure increased but also allowable minimum cavern pressure increased. For various flow rates, maximum numbers of injection and production days were obtained. At the end of simultaneous optimum production flow rate was found as 17.66 MMSCF/D, and optimum injection flow rate was found as 14.13 MMSCF/D for the optimum cavern depth.

Geological Sequestration of Anthropogenic Carbon Dioxide in the Western Canada Sedimentary Basin: Suitability Analysis

Abstract Geological sequestration of anthropogenic carbon dioxide is a potential solution to the release into the atmosphere of CO2, a greenhouse gas thought of as significantly contributing to the global warming trend observed since the beginning of the industrial revolution. Basically, CO2 can be sequestered in geological media:through enhanced oil recovery (EOR),by storage in depleted oil and gas reservoirs,through replacement by CO2 of methane in deep coal beds (ECBMR),by injection into deep saline aquifers, and by storage in salt caverns. Criteria in assessing the suitability of a sedimentary basin for CO2 sequestration are:tectonism and geology,the flow of formation waters and geothermal regime, andthe existence of storage media (hydrocarbon reservoirs, coal seams, deep aquifers and salt structures). Generally, the Western Canada Sedimentary Basin is suitable for CO2 sequestration by all means because it is tectonically stable, it has regional-scale aquifers confined by aquitards or aquicludes, and it has oil and gas reservoirs in various stages of depletion, uneconomic coal seams, and extensive salt beds. However, various regions in the basin have different degrees of suitability, ranging from not suitable along the eastern edge of the basin, to extremely suitable in southwestern and central Alberta. Most major CO2 producers, such as power plants and refineries around Edmonton, are found in regions that are unsuitable for CO2 sequestration in geological media; however, some, such as the oil sands plants in the Athabasca area, are in regions that are not suitable. This analysis of the suitability of the Western Canada Sedimentary Basin for CO2 sequestration in geological media should provide industry and governments with essential information needed for developing plans and policies in response to climate change effects of anthropogenic greenhouse gas emissions into the atmosphere. Introduction Human activity since the industrial revolution had the effect of increasing atmospheric concentrations of gases with a greenhouse effect, such as carbon dioxide (CO2) and methane (CH4), leading to climate warming and weather changes(1, 2). Because of its relative abundance compared with the other greenhouse gases, CO2 is by far the most important, being responsible for about 64% of the enhanced "greenhouse effect"(1). On a sectoral basis, the energy sector contributes globally the most (45%) to anthropogenic (produced by human activity) effects on climate change(3). The high use of fossil fuels (85% of the world's energy needs), foreseen to continue well into the future(2, 4), is the major contributor to increased emissions of CO2 into the atmosphere. Thus, a major challenge in mitigating anthropogenic (man-made) effects on climate change is the reduction of these emissions. Figure 1 shows Canada's profile in CO2 emissions by sector and by province. The profile of CO2 emissions in the Western Canada Sedimentary Basin is different from the national and other regions' profile because the basin is a major North American producer of fossil fuels.

Recent Salt Related Uplift and Subsidence at Sour Lake Salt Dome, Hardin County, Texas

ABSTRACT Sour Lake is a large piercement salt dome located in southern Hardin County, Texas. Recent deformation of the cellar and wellhead of one of the salt cavern storage wells initiated a geologic investigation into the cause of the deformation and its future impact. Unlike many of the other Gulf Coast salt diapirs that have a flat or inclined upper salt surface, the upper surface of the salt at Sour Lake is strongly domed with over 1000ft of relief. The geologic investigation showed that the diapir has maintained a near-surface position since at least Yegua time and appears to be characterized by a passive or down-building stage. However, the central area of the diapir has been an area of active uplift since late Frio time resulting in a complex graben system forming over the central area of the dome. The cause of the 1929 sinkhole occurrence at Sour Lake was re-evaluated and provided the basis for mapping the changes in ground level between 1923 and 1965. These changes in elevation show areas of uplift and subsidence that correspond to the underlying graben system. In addition to being located in the area of active uplift, the storage well experiencing the deformation is also located on a smaller and more active area of salt uplift (a salt spine). Since the late 1960's, this spine has begun moving and has resulted in the over-pressuring of the caprock and adjacent sands. Active salt movement at Sour Lake has resulted in uplift and extension of the overlying strata and has produced surface subsidence.

Sequestration of CO 2 in geological media: criteria and approach for site selection in response to climate change

Anthropogenic effects on climate can be mitigated through various measures, among them being CO 2 sequestration in geological media. Geological sinks for CO 2 do not really need any major technological development because the technology has already been developed and applied by the upstream energy industry for hydrocarbon exploration and production. The challenge is rather to identify the best methods and sites for long term CO 2 sequestration. There are various ways to sequester CO 2 in geological media: utilization in EOR operations, disposal in disused oil and gas reservoirs, replacement of methane in coal beds, injection in deep saline aquifers and storage in salt caverns. Several criteria have to be considered when evaluating the potential of a sedimentary basin for CO 2 sequestration: its tectonic setting and geology, the basin geothermal regime, the hydrodynamic regime of formation waters, the hydrocarbon potential and basin maturity, economic aspects relating to access and infrastructure and socio–political conditions. The range of sedimentary basins suitable for CO 2 sequestration is significantly reduced if these criteria and climatic conditions, accessibility, infrastructure and cost of CO 2 capture and injection are taken into account. A systematic approach is proposed for the assessment and selection of method and sites for CO 2 sequestration in geological media.

French gas-storage project nearing completion

Geomethane, jointly formed by Gaz de France and Geostock, is currently converting 7 of 36 solution-mined salt cavities at Manosque in southeast France from liquid hydrocarbon storage to natural-gas storage. In view of the large diameter (13 3/8 in.) of the original production wells and safety requirements, a unique high-capacity well completion has been developed for this project. It will have two fail-safe valves and a flow crossover 30 m below ground to isolate the production well in the event of problems at the surface. The project lies in the wooded Luberon Nature Reserve and due consideration has been given to locating the surface plant and blending it with the surroundings. The production wellheads are extra-low designs, the main plant was located outside the sensitive area, and the pipeline routes were landscaped. The paper discusses the history of salt cavern storage of natural gas; site characteristics; Manosque salt geology; salt mining and early storage; siting; engineering and construction; completion and monitoring; nature reserve protection; and fire and earthquake hazard mitigation.

Potential for Future Development of Salt Cavern Storage in the Upper Silurian Syracuse Formation of South-Central New York: ABSTRACT

Although depleted reservoirs remain the dominant structures used for storage fulfilling the demand for base load gas supply during the heating season, the current general surge in storage projects, nationwide, takes advantage of opportunities in Order 636, and makes greater use of salt caverns for gas storage. This reflects the increasing need by gas users, local distribution companies in particular, to quickly cycle a storage facility`s gas supply for services such as peak shaving, emergency supply, and system balancing to meet hourly swings. Occurrence of thick deposits of bedded salt deposits provides New York the capability to develop high deliverability salt cavern storage facilities. Furthermore, New York is uniquely positioned at the gateway to major northeastern markets to provide peak load storage services of natural gas supply. The thickest units of bedded salt in New York occur in the {open_quotes}F{close_quotes} horizon of the Upper Silurian Syracuse Formation. Three bedded salt cavern storage facilities have been recently proposed in New York. Two of these projects is much larger (with 5 Bcfg ultimate capacity), is under construction, and will provide valuable storage service to the Ellisburg-Leidy market center hub in Pennsylvania. Identification of possible sites for future salt cavern storage projects hasmore » been achieved chiefly by defining areas of thick beds of salt at sufficient depths close to gas transmission lines, with access to a freshwater supply for leaching, and possessing an acceptable method of brine disposal.« less

Storage in lined hard-rock cavens: results of a pilot study

Spiraling natural gas consumption has increased the demand for high-pressure underground gas storage facilities. The proven methods of gas storage in porous geological formations and salt caverns are limited to locations with suitable geological conditions. At present, innovative techniques for high-pressure underground gas storage in lined hard rock caverns are being investigated in order to increase the number of potential sites and raise supply security. Because of the permeability of the generally jointed hard rock masses, these caverns have to be sealed by a lining system. This paper reports the results of a feasibility study of high-pressure gas storage in lined hard rock caverns. The paper commences with a look at the potential uses of hard rock caverns for gas storage, and pertinent design requirements. A preliminary concept for the caverns and the gas plant is discussed, with specific emphasis on geological boundary conditions, rock mechanics and construction. The paper concludes with a discussion of technical and economic feasibility considerations for this storage concept. La consommation de gaz a naturel a augmenté la demande pour des centres de stockages souterrains de gaz haute-pression. Les méthodes bien connues du stockage du gaz dans les formations géologiques poreuses ou dans les cavernes de sel sont limitées à des regions ayant des conditions géologiques appropriées. A présent, des innovations techniques pour le stockage souterrain du gaz à haute pression dans des cavernes creusées dans de la roche dure ont été recherchées de façon augmenter le nombre de sites potentiels et la sécurité d'approvisionnement. A cause de la perméabilité de la matrice rocheuse généralement fracturée, ces cavernes doivent être rendues étanches par un systéme de revêtement. Cet article rend compte de résultats de l'étude de faisabilité du stockage du gaz à haute-pression dans les cavernes creusées dans la roche dure. Cet article débute en s'intéressant à l'utilisations potentielle de ce type de caverne pour le stockage de gaz, et aux conditions requises pour un design pertinent. Une conceptions préliminaire des cavernes et de l'usineé gaz est discuté, en insistant particuliérement sur les conditions géologiques limites, la mécanique des roches et la construction. L'article conclut par une discussion sur des considérations de faisabilité au point de vue technique et économique pour ce concept de stockage.

Stability of gasolines during storage in salt caverns

Stability of gasolines during storage in salt caverns

Economic Considerations Concerning the Use of Salt Caverns for Natural Gas Storage by an Integrated Natural Gas Transmission and Distribution System

Abstract The system under discussion, that of the Saskatchewan Power Corporation, transmits and distributes natural gas to customers whose numbers are small inrelation to the transmission distances involved. The severe continental climate coupled with the long transmission distances make the expense of meeting the peak demands imposed on the system particularly onerous. Although the systemhas available depleted gas fields that are satisfactory for storage, both in adeveloped and in a potential state, none of these reservoirs are close enoughto the load centers to alleviate the demand on major transmission systems. Much of southern Saskatchewan is underlain by the Prairie Evaporite formation, which consists mainly of potassium and sodium chlorides. This formation occurs in thicknesses of up to 600 feet, and at depths ranging from 2,500 to 7,000 feet. The Corporation has undertaken to develop natural gas storage in caverns that have been washed from the Prairie Evaporite formation by a solution mining process. Two of these caverns are presently in operation, and a third is in theprocess of being washed out. The economic considerations for developing these caverns are quite different from the considerations governing the development of a conventional storage field. The differences in these considerations arise, first, from the fact that the size of the reservoir is controllable and, secondly, because this type of reservoir has a relatively limited total volume compared to its delivery capability. This paper will outline the techniques bywhich the Corporation has attempted to analyse the relationship between pipe-line capacity arid cavern storage volume in order to fulfill the system requirements at minimum cost. The Corporation's System The Saskatchewan Power Corporation's natural gas transmission system extends throughout the populated area of Saskatchewan. With service to all of Saskatchewan's cities and most towns, the total number of customers served at year-end 1964 was 105,251.

The Use of Salt Cement Blends as an Aid to Better Cementing in Formations Containing Fresh Water Sensitive Clays

Abstract The application of salt for primary cementing in Western Canada has been restricted largely to salt cavern storage wells and to the development of potash reserves in south-central Saskatchewan. The value of salt cement blendsin cementing through fresh water sensitive formations has recently broughtabout wide usage of this technique in certain areas of the United States, andthere is good reason to believe that there are several areas in Canada wherethe success of primary cementing could be improved by the use of saltcements. There has been considerable work done on the applicability of salt cement, with emphasis on improved cement-formation bonding and the minimization offormation deterioration by water contact. Field results have shown that saltcements have improved the success of primary and squeeze cementing jobs. Laboratory work has been done to evaluate the change in slurry properties with the addition of varying concentrations of salt to commonly used cementing blends. Introduction The use of salt cements in Canada has been quite limited and, as a result, the primary purpose of the information presented here is to illustrate theadvantage of salt for primary cementing of oil and gas wells where the formations encountered contain fresh water sensitive clays and shales. The first known use of salt cements in Western Canada occurred within thepast ten years. Initially, salt cements came into use because of the failure toset fresh water cement abandonment plugs in the salt and potash zonesencountered in potash test holes. Earlier experience in the U.S.A. proved that a good cement-formation bond through a salt section could only be achieved byusing a salt cement. Figure 1 illustrates the bonding of cement to rocksalt. The illustration shows how a fresh water slurry will dissolve a portionof the salt, with the result that there is no bond between the salt and cement, while the saturated salt slurry does not dissolve any portion of the salt, resulting in good contact and bonding between the salt and the cement. Operators in Saskatchewan found that casing could be cemented successfully in salt cavern gas storage wells with a sodium chloride slurry; more recentwork has employed a sodium chloride and potassium chloride (potash) saturated slurry (1). Later, casing was set into the potash for a solution mining project, and again salt cements were used to obtain a good primary cement job.