163 results about "Underground gas storage" patented technology

The invention relates to a construction method for a gas storage reservoir in a rock salt cavity, belongs to the salt mine mining and the rock salt cavity utilization fields, and mainly used for the dissolution construction of an underground gas storage reservoir in a eutectic salt deposit. The construction method is characterized in that a method for down-flow type gas storage reservoir construction comprises the following steps: fresh water is infused into a salt deposit by a water injection pump and through a water injection pipe, the rock salt is dissolved from up to down, and at the same time, the natural gas is infused; the expenses for oil consumption of the original oil cushion method and the cost for brine purification treatment can be saved by using the method; and the method is more economical and more environment-friendly. The gas storage reservoir can be used from the beginning of construction; the single well oil cushion method with three to five years of construction cycle is not required for constructing the gas storage reservoir; the construction of the gas storage reservoir needs no cycle basically; the reservoir storage capacity is small in the beginning period; the gas storage reservoir can be used as a large gas storage reservoir in the middle and the late periods; the problems of long period for the construction of the gas storage reservoir by using the oil cushion method, difficult detection of the oil water interface, as well as other relative technical problems are thoroughly solved; and the construction method is an ideal method for rapid dissolution construction of the gas storage reservoir in the rock salt deposit.

The invention relates to a correction method for reasonable productivity prediction of an underground gas storage well. The method comprises the following steps that a gas well binomial productivity equation (inflow curves) represents the supply capacity of a stratum; the flowing capacity of an oil pipe under the condition of limited pipe diameter of the oil pipe is determined through the oil pipe flowing capacity (outflow curve); the maximum flowing capacity of a gas well under the condition of the oil pipe can be obtained through combined intersections of the curves; for the production capacity of the gas well, limits to reasonable production pressure differences also shall be taken into consideration besides the capacity of the intersections of the inflow curves and the outflow curve. According to the invention, the intersections of the inflow curves and the outflow curve are corrected through establishing reasonable production pressure differences of the gas well, and the reasonable productivity of the gas well is obtained after correction. The method is simple in calculation, conforms to the actual situation, and can further guide the design of the gas storage effectively.

The invention discloses a salt-cavern gas storage twin-well building method, and belongs to the technical field of technology for building salt-cavern gas storages. The salt-cavern gas storage twin-well building method comprises the steps of: first, respectively drilling a first well and a second well, wherein the distance between the center lines of the first and second wells is 15m-30m; second, communicating the first and second wells through a natural dissolution method, and circularly building cavities for the first and second wells; third, injecting gas into the first well, discharging brine water from the second well; fourth, performing gas injection and recovery to the first or second well, or simultaneously performing gas injection and recovery to the first and second wells. According to the salt-cavern gas storage twin-well building method, respectively through injecting water into the first well and discharging brine water from the second well, the water injection volume is increased, the cavity building speed is enhanced, and the storage building period is shortened; respectively performing solution mining to the cavities of first and second wells by a single well convection method, the storage is built by fully utilizing salt beds, the dissolution volume of the cavity is enlarged, the cavity form and stability are ensured, and thus the gas storage is ensured to operate safely.

A method for constructing an underground gas storage by a depleted oil-gas reservoir includes the steps: firstly, drilling a well; secondly, performing injection-production well completion interaction; thirdly, controlling injection-production well safety; fourthly, optimizing corrosion prevention; fifthly, monitoring formation parameters; sixthly, plugging an old well; and seventhly, expanding water drainage capacity. The method has the advantages that reservoir protection effects are obvious, matching technology is safe, environment-friendly and energy-saving, a well field and a wellhead are reasonably arranged, drilling speed is high, complex well drilling accidents are prevented, the requirements of an injection-production well on safety production and operation can be met, and the underground gas storage is large in storage volume, high in mobility and wide in peak-shaving range.

A system and method are provided for short term trading in gas and/or gas derivatives. In a preferred embodiment, the system provides a plurality of shallow depth salt gas storage facilities. Each of the facilities is typically operated at pressures in a range close to the pipeline pressure, typically within a range of 20 to 80 bars. If trading results in a difference to be made up, then computers operating the facilities respond quickly to add or remove gas from the pipelines, as required, with a response time as low as two minutes to change the net direction of flow of gas into or out of the storage facilities.

The invention relates to a gas storage and heat storage integrated hot dry rock reheating compressed air energy storage system. The gas storage and heat storage integrated hot dry rock reheating compressed air energy storage system comprises a plurality of compressors and a plurality of expansion units, wherein the compressors are connected with a motor through couplings; the adjacent compressors are connected with one another through heat accumulators; the last-stage compressor is connected with an inlet of an underground gas storage well group; an outlet of the underground gas storage well group is connected with the first expansion unit; the first expansion unit is connected with a gas flow inlet of a heat exchanger through a heat accumulator; a gas flow outlet of the heat exchanger is connected with the second expansion unit; a working medium inlet and a working medium outlet of the heat exchanger are connected with a hot dry rock heat collecting system through pipes to form a circulation loop; the heat exchanger and the hot dry rock heat collecting system form a reheating system; when the number of the expansion units is greater than 2, reheating systems are separately arranged among the adjacent expansion units behind the first expansion unit. Heat of interstage cooling of the compressors is recycled in a compression stage, air of interstage reheating is preheated in an energy releasing stage, heat loss of the system is reduced effectively, and the efficiency of the system is improved.

Disclosed is an old well plugging method for constructing an underground gas storage by a depleted oil-gas reservoir. In order to prevent natural gas injected into the gas storage from channeling to a position close to an old well borehole along a gas reservoir, or vertically migrating along a first interface and a second interface of an oil well cement ring or channeling into a shaft along a perforated hole and migrating towards a non-gas-storage layer and a wellhead, the gas reservoir is plugged by a high-pressure squeezing process, a multi-stage cement plug is driven into the shaft to plug the shaft, and the length of a continuous cement plug above a top boundary of the gas reservoir is larger than or equal to 300m. If the top of cement above the top boundary of the gas reservoir is larger than 200m and a continuous cement bond section below a cap rock of the top boundary of the gas reservoir is larger than 25m, the continuous cement plug can be directly injected in a sectioned manner. If the top of cement above the top boundary of the gas reservoir is smaller than 200m and the continuous cement bond section below the cap rock of the top boundary of the gas reservoir is smaller than 25m, the cap rock above the top boundary of the gas reservoir is forged and milled by a casing, the forging and milling length is larger than or equal to 30m, and the continuous cement plug is injected in a sectioned manner after forging and milling. The old well plugging method has the advantage that the natural gas entering the casing is effectively prevented from migrating towards the non-gas-storage layer and the wellhead.

The present invention relates to a metal shaft detection device of the underground gas storage well, and belongs to the technical field of security detection of the underground gas storage well. The detection device comprises a ground processing part and an underground detection part; wherein, the ground processing part mainly comprises a data receiving unit, a winch unit, a host computer and a display; the underground detection part comprises a magnetic flux leakage sensor, a magnetic flux leakage signal processing module, a first A/D conversion unit, an ultrasonic sensor, an ultrasonic signal processing module, and a second A/D conversion unit; the magnetic flux leakage sensor, the magnetic flux leakage signal processing module and the first A/D conversion unit are connected in sequence; the ultrasonic sensor, the ultrasonic signal processing module and the second A/D conversion unit are connected with each other; one end of the two A/D conversion units is connected with an embedded computer system, and the other end is connected with a position distance recording unit. The detection device integrates the characteristics of the magnetic flux leakage detection and the ultrasonic detection, can effectively detect the corrosion, fatigue crack and other phenomena of the metal shaft in use, and has the advantages of high reliability and strong on-site adaptability.

The invention discloses an internal-pressure fatigue test device for a well-completion pipe string of an underground gas storage reservoir and a test method thereof and belongs to the technical field of petroleum drilling well completion. The test device includes a pressure transmission mechanism, enclosed cavity mechanisms, a control system, leakage detection systems and a pipe string sample. The pressure transmission mechanism passes through an internal cavity of the pipe string sample from top to bottom. The upper and lower ends of the pipe string sample are packaged through the enclosed cavity mechanisms. The enclosed cavity mechanisms are connected with the control system. The leakage detection system is installed on the pipe string sample. Therefore, a test device of a simulating gas storage reservoir well-completion pipe string in a gas injection and gas production process is formed so that radial pressure change data of the well-completion pipe string are obtained. The internal-pressure fatigue test device for the well-completion pipe string of the underground gas storage reservoir and the test method thereof are capable of detecting the sealing performance and fatigue strength of well-completion pipe string joints under a plurality of changes of an internal pressure through use of a fatigue test machine so as to obtain the radial pressure change data and thus a design basis is provided to oil-field work personnel and operating parameters of the gas storage reservoir are optimized.

The invention discloses an installation method of a double-walled sleeve suspended type high pressure gas underground gas storage well, and a structure thereof, wherein, the method comprises the following steps: well drilling is carried out; an outer mineshaft body is welded and sunk into the drilled well, the upmost end of the outer mineshaft body is connected with a lower-side heteromorphic equipment flange with a groove in a welding way; cement is injected to form a well cementation layer and a groundwork layer, and the groundwork layer is pre-embedded with a plurality of anchor bolts; the anchor bolts are connected and fixed with the lower-side heteromorphic equipment flange; an internal mineshaft is installed in the outer mineshaft body; two split heteromorphic equipment flanges are compressed on the upper end face of the upmost section hoop, and then the split heteromorphic equipment flanges are clamped with the lower-side heteromorphic equipment flange by bolts; and nitrogen is introduced between the internal mineshaft and the outer mineshaft body. By adopting the device and the well cementation method, the stored gas can be prevented from leaping to the outside of the well, sinking and leakage, and the gas storage well can bear the corrosion of the outer wall of the mineshaft, thus guaranteeing the axial elongation of the gas storage well when bearing pressure.

The invention relates to a method for fixing underground gas storage well cylinder, which comprises a well cylinder whose bottom has a one-way valve and a fixing bracket inside the basic well; a irrigating device for mounting insertion tube and modulating the cement via the cement pump, insertion tube, and one-way valve to fill cement into the cylinder and the well wall; then removing the irrigating device; and waiting the cement be solidified. The invention can avoid pollution on the inner chamber of well cylinder, to eliminate the washing process. And it can improve the safety and service life of well cylinder.

The invention relates to a mine shaft of high-pressure gas underground storage well and the fixed method. The mine shaft comprises shaft body, connecting sleeve, four-way control head, one-way sealing head and foundation fixed bracket on the bottom, and drainage pipe. The fixed method comprises drilling base well, setting shaft body, producing cement slurry, cement slurry perfusion along inner cavity of mine shaft and one-way valve, installing drainage pipe and four-way control head. Because of one-way valve applied as bottom sealing head of mine shaft, base fixed bracket added, and cement slurry perfusion improved, it is provided with reasonable structure design, convenient and stable operation for perfusion, fixed connection between the mine shaft and well wall, good safety, convenient repair and maintenance, and longer service life so on. Inconvenient assembling and fixing well shaft, small attachment force with cement, bad stability of perfusion fixing technology, uneasy operation, mine shaft rotating or moving in working and bad safety are conquered.

The invention belongs to the technical field of well drilling and discloses an underground natural gas storage injection-production pipe column designing method. By comprehensively considering the influence on a pipe column from self weight of a pipe body, the temperature effect, the pressure effect and the friction effect generated by fluid flowing, on the basis of design of an existing pipe column, compression loads are considered and matched with the compression efficiency of a pipe column connector to design an underground natural gas storage injection-production pipe column, it is ensured that the compression efficiency of a connector of the designed pipe column meets the operation compression load and sealing requirements, and meanwhile as the triaxial stress of the pipe column is considered for design, the overall structural intensity of the injection-production pipe column can meet the operation load requirement. The underground natural gas storage injection-production pipe column designing method not only can meet the airtightness under stretching loads, but also can meet the airtightness of the pipe column after stretching and compression loads interchange, improve the sealing performance of the pipe column under the interchanged loads and ensure long-term safety operation of the injection-production pipe column.

The invention discloses a site selection assessment method for a water-bearing stratum underground gas storage and belongs to the technical field of natural gas resource exploration and development. The method comprises the steps that suitability degrees corresponding to technical indexes of candidate sites of the water-bearing stratum gas storage are obtained according to the site selection technology, the geology safety, the economy and the social environment characteristic; an analytic hierarchy process is adopted for determining weight values of all the technical indexes; according to the suitability degrees corresponding to all the technical indexes and the weight values of all the technical indexes, the comprehensive storage construction suitability degree of each candidate site of the water-bearing stratum gas storage is obtained; the assessment result is obtained according to a preset classification list of the suitability degrees of the site selection indexes of the water-bearing stratum gas storage. According to the method, the technical principle, the determining method and steps of the site selection of the water-bearing stratum underground gas storage are defined, the measurability is high, and the scientific and reasonable technical method is provided for exploration and construction of the water-bearing stratum gas storage.

The invention relates to a method for detecting a setting effect of a packer in a salt-cavern gas storage. The method comprises the following steps: 1) washing a well after tripping in an injection-production casing; 2) injecting nitrogen into an annulus between the injection-production casing and a production casing, pressurizing brine in the annulus to below a packer setting position; 3) after setting the packer, continuing to inject nitrogen into the annulus to pressurize so that an annulus pressure of the packer at least is 1.1 times greater than an upper limit pressure of the salt-caverngas storage; 4) tripping in a gas-liquid interface inspection device in the injection-production casing, and detecting a gas-liquid interface below the packer between the injection-production casing and the production casing; 5) detecting and recording the depth of the gas-liquid interface, the wellhead pressure of the injection-production casing and the annulus pressure; and 6) judging the setting effect of the packer according to change situations of the gas-liquid interface below the packer, the wellhead pressure of the injection-production casing and the annulus wellhead pressure. The method is strong in practicability, simple to operate, high in airtightness detection precision, and helpful for effectively verifying the setting effect of the packer, so as to prolong the life of the salt-cavern underground gas storage and ensure safe and effective operation of the same.

The invention relates to a simulation experiment device for a fault with multi-period alternating stress, and mainly solves a problem of low possibility of judging fault sealing property of an existing underground gas storage. The simulation experiment device is characterized by comprising a core preparation system, a vacuumizing assembly, a host model system, a data collection and analysis system and a pressure injection system. The device can not only test sealing property parameters of a fault sample of the storage but also realize simulation of a stress state and the like of the sample of the storage under a multi-period alternating stress condition for real-time continuous monitoring, and further can perform comprehensive evaluation on sealing conditions of the fault of the storage under the multi-period alternating stress operation condition in combination with other geological conditions (such as lithologic characters, fault fillers, fault parameters and the like) of the storage.

The invention discloses a method for manufacturing an underground gas storage device for storing special gas. The method includes the following steps that S1, materials are selected, and it is guaranteed that material components of a low-alloy structure steel assembly of the underground gas storage device meet the requirement; S2, degreasing and passivating are conducted on the underground gas storage device; S3, examination and acceptance inspection are conducted; S4, the low-alloy structure steel assembly of the underground gas storage device is assembled, a pipe opening is sealed, the sealed pipe is placed downwards into an uncased hole well, well cementation is conducted, and a well opening device is mounted. The method has the advantages that special gas such as hydrogen, oxygen, helium or industrial exhaust gas are stored through an underground gas storage well, a prepared acid cleaning agent, a degreasing agent, passivator and a circulating degreasing agent are adopted, the cleaning and passivation effects of the underground gas storage device are guaranteed, and the applicability and stability of the device for storing the special gas are guaranteed.

The invention relates to the field of development of horizontal wells of underground gas storage wells, and particularly relates to a device for measuring the frictional resistance coefficient of gas in the underground gas storage well and monitoring the vibration of a tubular column. A system comprises four parts of a gas control unit, a pipeline testing unit, a vibration device unit and an acquisition control unit, wherein the gas control unit comprises a screw compressor, a buffer tank and a gas mass flow controller, the buffer tank is connected between the screw compressor and the gas mass flow controller; the pipeline testing unit comprises a simulating pipeline and a sensor; and the vibration device unit comprises a vibration sensor group and an upper computer, and a vibration sensor comprises an acceleration sensor. The acquisition control unit is realized by connecting a computer with a test device in series. The frictional resistance coefficient of the gas in the tubular column of the underground gas storage well is measured, the vibration performances of the tubular column under the working conditions of injection and extraction are monitored, and the structure integrity of the tubular column of the underground gas storage well and the safety of the whole well are guaranteed.