Temperature control device for gas storage and parameter determination method thereof

Abstract

The invention belongs to the technical field of gas storage temperature control, and particularly discloses a temperature control device for a gas storage and a parameter determination method of the temperature control device. The parameter determination method comprises the steps that the temperature difference of an inlet and an outlet of a heat exchange pipe in the temperature control device is obtained, and the gas internal energy difference before and after gas inflation of the gas storage is determined; the temperature control device is arranged in a lining layer of the gas storage; the overflowing diameter of the heat exchange tube is determined according to the temperature difference and the gas internal energy difference; and the minimum wall thickness of the heat exchange tube is determined according to the overflowing diameter of the heat exchange tube, the allowable stress and the maximum pressure borne by the heat exchange tube. Redundant heat can be taken away when the gas storage is inflated, and heat is supplemented into the gas storage when the gas storage is deflated, so that the temperature of the gas storage is relatively stable, the influence of temperature load on a lining layer is reduced, the reliability of the gas storage is improved, and the service life of the gas storage is prolonged. And meanwhile, the inflating and deflating efficiency can be ensured, so that the gas storage can operate normally.

Description

Technical Field

[0001] The invention discloses a temperature control device for a gas storage and a parameter determination method thereof, belonging to the technical field of temperature control of gas storage. Background Art

[0002] In the operation process of underground gas storage, accurate and efficient temperature control has become an indispensable element to ensure the safe, stable and efficient operation of the system. In the frequent gas filling and degassing cycles, the gas state undergoes drastic changes. When filling, the gas is affected by the work of the compressor, and the pressure and amount of matter increase sharply. Following the laws of thermodynamics, the internal energy rises, causing the temperature in the storage to rise sharply; in the degassing stage, the gas expands and does work externally, the internal energy decreases sharply, and the temperature drops sharply. This large fluctuation in temperature has led to many difficult problems.

[0003] On the one hand, the drastic temperature fluctuations impose strong thermal stress on the lining structure of the gas storage reservoir. After long-term accumulation, the lining material cannot bear the stress, fatigue damage is aggravated, cracks initiate and expand, and seriously endanger the structural integrity and sealing of the gas storage reservoir. Once the lining fails, it will not only cause gas leakage and reduce energy storage efficiency, but it is also likely to cause geological safety hazards and threaten the surrounding environment.

[0004] On the other hand, unstable temperature conditions interfere with the physical properties of compressed air, such as density and viscosity, which hinders gas compression, storage and subsequent efficient release and utilization, reduces the overall performance of the energy storage system, and increases energy loss and operation and maintenance costs.

[0005] In order to reduce the negative impact of large temperature fluctuations on gas storage facilities, the existing technology usually adjusts the operating conditions, which has the problem of affecting gas storage efficiency and affecting the normal operation of the gas storage facilities. Summary of the invention

[0006] The purpose of the present invention is to provide a temperature control device for a gas storage and a parameter determination method thereof, so as to solve the technical problems in the prior art of achieving temperature control of the gas storage by adjusting the operating conditions, which affect the gas storage efficiency and the normal operation of the gas storage.

[0007] A first aspect of the present invention provides a method for determining parameters of a temperature control device for a gas storage reservoir, comprising: obtaining the temperature difference between the inlet and outlet of a heat exchange tube in the temperature control device and determining the internal energy difference of the gas before and after the gas storage reservoir is inflated, wherein the temperature control device is arranged in a lining layer of the gas storage reservoir; determining the flow diameter of the heat exchange tube according to the temperature difference and the internal energy difference of the gas; determining the minimum wall thickness of the heat exchange tube according to the flow diameter of the heat exchange tube, the allowable stress and the maximum pressure that the heat exchange tube can withstand.

[0008] Preferably, determining the difference in gas internal energy before and after the gas storage is inflated specifically includes: determining an inflation correction coefficient based on inflation parameters of the gas storage; and determining the difference in gas internal energy before and after the gas storage is inflated based on the inflation correction coefficient and the temperature of the gas storage before and after the gas storage is inflated.

[0009] Preferably, the inflation parameters include at least one of inflation speed, inflation pressure, inflation time and constant volume specific heat capacity.

[0010] Preferably, the difference in gas internal energy before and after the gas storage reservoir is inflated is determined based on the inflation correction coefficient and the temperature of the gas storage reservoir before and after inflation, specifically including: determining the gas internal energy before the gas storage reservoir is inflated based on the product of the temperature before the gas storage reservoir is inflated and the inflation correction coefficient; determining the gas internal energy after the gas storage reservoir is inflated based on the product of the temperature after the gas storage reservoir is inflated and the inflation correction coefficient; determining the difference between the gas internal energy after the gas storage reservoir is inflated and the gas internal energy before the gas storage reservoir is inflated, to obtain the gas internal energy difference.

[0011] Preferably, the flow diameter of the heat exchange tube is determined according to the temperature difference and the internal energy difference of the gas, specifically including: determining the volume flow rate of the heat exchange tube according to the temperature difference and the internal energy difference of the gas; determining the flow diameter according to the volume flow rate and the flow velocity of the heat exchange medium in the heat exchange tube.

[0012] Preferably, the volume flow rate of the heat exchange tube is determined according to the temperature difference and the internal energy difference of the gas, specifically including: determining the mass flow rate of the heat exchange tube according to the temperature difference and the internal energy difference of the gas; determining the volume flow rate of the heat exchange tube according to the mass flow rate and the density of the heat exchange medium.

[0013] Preferably, the minimum wall thickness of the heat exchange tube is determined according to the flow diameter of the heat exchange tube, the allowable stress and the maximum pressure that the heat exchange tube can withstand, specifically including: determining the product of the flow diameter of the heat exchange tube and the maximum pressure that the heat exchange tube can withstand; and determining the minimum wall thickness of the heat exchange tube according to the quotient of the product and the allowable stress.

[0014] The second aspect of the present invention provides a temperature control device for a gas storage reservoir, whose parameters are determined by using the parameter determination method of the temperature control device for a gas storage reservoir mentioned above, wherein the heat exchange pipe includes a heat exchange inlet pipe and a heat exchange outlet pipe; the heat exchange inlet pipe is a spiral structure, which is wound in the lining layer of the gas storage reservoir along the axial direction of the gas storage reservoir, and the inlet of the heat exchange inlet pipe extends out of the lining layer; the heat exchange outlet pipe is pre-buried in the lining layer, one end of which is connected to the outlet of the heat exchange inlet pipe, and the other end extends out of the lining layer.

[0015] Preferably, the ratio of the thickness of the lining layer to the distance between the heat exchange inlet pipe and the inner surface of the lining layer is 1:0.3-0.4.

[0016] Preferably, the pitch of the spiral structure is 1m-2m and is greater than or equal to a preset multiple of the thickness of the lining layer.

[0017] Compared with the prior art, the temperature control device for gas storage and the parameter determination method thereof of the present invention have the following beneficial effects: The present invention can take away excess heat when the gas storage is inflated, and replenish heat into the gas storage when the gas storage is deflated, thereby making the temperature of the gas storage relatively stable, reducing the impact of temperature load on the lining layer, and improving the reliability and service life of the gas storage. At the same time, it can ensure the efficiency of inflation and deflation, so that the gas storage can operate normally. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a flow chart of a method for determining parameters of a temperature control device for a gas storage according to an embodiment of the present invention.

[0019] Figure 2 Schematic diagram of the structure of the gas storage in an embodiment of the present invention.

[0020] In the figure: 1 is the heat exchange inlet pipe; 2 is the lining layer; 3 is the sealing layer; 4 is the sealing door; 5 is the plug; 6 is the heat exchange outlet pipe; 7 is the inlet valve; 8 is the outlet valve; 9 is the inlet thermometer; 10 is the outlet thermometer. DETAILED DESCRIPTION

[0021] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present invention. However, it should be clear to those skilled in the art that the present invention may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present invention.

[0022] A first aspect of an embodiment of the present invention provides a method for determining parameters of a temperature control device for a gas storage, such as Figure 1 As shown, including: Step 1: Obtain the temperature difference between the inlet and outlet of the heat exchange tube in the temperature control device and determine the gas internal energy difference before and after the gas storage is filled, wherein the temperature control device is arranged in the lining layer of the gas storage, specifically including: Step 1.1: Determine the internal energy difference of the gas before and after the gas storage is filled, including: Step 1.1.1, determine the inflation correction coefficient according to the inflation parameters of the gas storage reservoir.

[0023] Taking into account that the inflation correction coefficient is related to factors such as inflation speed, inflation equipment, gas properties, operating conditions, etc., the inflation parameters defined in the embodiment of the present invention include at least one of inflation speed, inflation pressure, constant volume specific heat capacity and inflation time that can reflect the above factors.

[0024] Exemplarily, the method for determining the inflation correction coefficient is described by taking the inflation parameters including the inflation speed, the inflation pressure, the constant volume specific heat capacity and the inflation time as an example.

[0025] Inflation correction factor of the embodiment of the present invention Determined according to the following first formula.

[0026] (1) In the formula is the inflation speed, is the maximum inflation speed that can be achieved under the operating conditions of the inflation equipment and gas storage. Indicates the relative size of the inflation speed; is the inflation pressure, is the initial pressure of the gas storage reservoir, The maximum pressure that the inflatable device can reach. Reflects the degree of pressure applied by the inflatable equipment; is the specific heat at constant volume, is the average value of the constant volume specific heat capacity of common gases, where common gases can be air and carbon dioxide. It reflects the influence of the specific heat capacity characteristics of a particular gas on the inflation; Design time for inflation, The maximum possible time for one inflation operation. Indicates the relative length of inflation time; is the weight coefficient of each factor, is a constant term, taking into account the complexity of the gas storage structure. The weight coefficient distribution is shown in Table 1.

[0027] Table 1 Weight coefficient

[0028] Step 1.1.2, determine the difference in gas internal energy before and after the gas storage reservoir is filled with gas according to the filling correction coefficient and the temperature of the gas storage reservoir before and after the filling.

[0029] The above-mentioned gas internal energy difference in the embodiment of the present invention will be converted into heat to increase the temperature in the gas storage, so it is the heat that needs to be taken away by the heat exchange pipe. Since the inner wall of the gas storage can be considered to be a constant temperature within a certain range during long-term operation, the heat absorbed by the inner wall is ignored in the embodiment of the present invention. Similarly, the heat that needs to be supplemented during the degassing process can also be calculated.

[0030] According to the gas state equation of formula (2), the embodiment of the present invention can respectively determine the temperature of the gas storage before and after filling.

[0031] (2) In the formula, is the inflation pressure, i.e. the internal pressure of the gas storage, is the volume of the gas storage reservoir, is the amount of gaseous substance, is the universal gas constant, It is the temperature. During the inflation process, the inflation pressure and the amount of material increase, and the temperature also rises.

[0032] In the embodiment of the present invention, the pressure of the gas storage before inflation is the atmospheric pressure, and the pressure after inflation is the design pressure. Therefore, the temperature of the gas storage before inflation can be determined according to the above formula (2): and the temperature after inflation .

[0033] For an ideal gas, the internal energy is proportional to the temperature. Therefore, the embodiment of the present invention is based on the temperature of the gas storage before filling. and inflation correction factor The product of determines the internal energy of the gas before filling the gas storage tank , as shown in formula (3).

[0034] (3) In the formula, is the inflation correction factor, is the specific heat at constant volume, It is the amount of gas in the gas storage before inflation, that is, the amount of air. The temperature of the gas reservoir before filling it.

[0035] According to the temperature of the gas storage after filling and inflation correction factor The product of determines the internal energy of the gas after the gas storage is filled , as shown in formula (4).

[0036] (4) In the formula, is the inflation correction factor, is the specific heat at constant volume, is the amount of gas in the gas storage after inflation, The temperature of the gas storage after filling.

[0037] In getting and Finally, determine the difference between the internal energy of the gas after the gas storage is filled and the internal energy of the gas before the gas storage is filled. , we get the gas internal energy difference, as shown in formula (5).

[0038] (5) The above gas internal energy difference determined by the embodiment of the present invention is is the heat that needs to be taken away by the heat exchange tube during the inflation process. If it is the deflation process, then The heat required to be supplemented by the heat exchange tube during the deflation process.

[0039] Step 1.2, obtaining the temperature difference between the inlet and outlet of the heat exchange tube in the temperature control device.

[0040] The heat exchange tube in the embodiment of the present invention includes a heat exchange inlet tube and a heat exchange outlet tube, so that the heat exchange medium flows into the heat exchange inlet tube and flows out from the heat exchange outlet tube. The temperature difference between the inlet and outlet of the heat exchange tube is the temperature difference between the inlet of the heat exchange inlet tube and the outlet of the heat exchange outlet tube. , The value is determined based on the actual project or the performance of the cooling system, usually between 5° and 10°.

[0041] The heat exchange medium in the embodiment of the present invention may be water or heat transfer oil.

[0042] Step 2: Determine the flow diameter of the heat exchange tube according to the temperature difference and the gas internal energy difference, specifically including: Step 2.1: Determine the volume flow rate of the heat exchange tube according to the temperature difference and the gas internal energy difference, specifically including: Step 2.1.1: Determine the mass flow rate of the heat exchange tube based on the temperature difference and the gas internal energy difference , as shown in formula (6).

[0043] (6) In the formula, is the heat, which is approximately equal to , is the specific heat capacity of the heat transfer medium, The temperature difference between the inlet and outlet of the heat exchange tube.

[0044] Step 2.1.2: Determine the volume flow rate of the heat exchange tube based on the mass flow rate and the density of the heat exchange medium. , as shown in formula (7).

[0045] (7) In the formula, is the mass flow rate of the heat exchange tube, is the density of the heat transfer medium.

[0046] Step 2.2: Determine the flow diameter of the heat exchange tube according to the volume flow rate and the flow rate of the heat exchange medium in the heat exchange tube. .

[0047] In the embodiment of the present invention, the flow diameter of the heat exchange tube is determined When calculating the flow rate of the heat exchange medium in the heat exchange tube, it is also necessary to consider the flow rate of the heat exchange medium in the heat exchange tube. Too high a flow rate will lead to excessive resistance, increase the energy consumption of the heat exchange pump and the wear of the heat exchange tube; too low a flow rate may cause uneven flow and affect the heating and cooling effect. It is best to control it between 1m / s and 3m / s. The flow area can be determined according to the following formula (8): .

[0048] (8) The heat exchange tube in the embodiment of the present invention is a round tube, and the flow area can be Determine the flow diameter of the heat exchange tube .

[0049] Step 3: Determine the minimum wall thickness of the heat exchange tube according to the flow diameter of the heat exchange tube, the allowable stress and the maximum pressure that the heat exchange tube can withstand, specifically including: determining the product of the flow diameter of the heat exchange tube and the maximum pressure that the heat exchange tube can withstand; determining the minimum wall thickness of the heat exchange tube according to the quotient of the product and the allowable stress , as shown in formula (9): (9) In the formula, is the maximum pressure that the heat exchange tube can withstand, which is the maximum pressure obtained by comprehensively considering the internal pressure of the gas storage reservoir, the internal pressure of the heat exchange tube, and the external soil and rock pressure. is the flow diameter, The embodiment of the present invention takes into account the corrosion allowance of the pipe material, so the wall thickness of the heat exchange tube is selected according to the principle of rounding up.

[0050] The present invention starts from the perspective of heat exchange calculation, closely follows the two main points of gas state and charging rate, and thus provides a basis for subsequent heat exchange tube arrangement and parameter design.

[0051] The present invention can achieve precise temperature control, and through accurate heat exchange calculation, the temperature control device can better adapt to different working conditions. Whether it is the temperature increase caused by the increase in gas internal energy during inflation, or the heat required to be supplemented during deflation, effective heat regulation can be performed through the heat exchange tube.

[0052] The present invention comprehensively considers the heat demand, the temperature difference between the inlet and outlet of the heat exchange tube, and the flow rate of the heat exchange medium in the heat exchange tube. By reasonably selecting the flow diameter and controlling the flow rate, it ensures that there is enough heat exchange medium to take away or provide the required heat, and avoids the problems of excessive resistance and increased energy consumption of the water pump caused by too high a flow rate, as well as unevenness and poor heating and cooling effects caused by too low a flow rate, thereby improving the energy utilization efficiency of the entire system and achieving efficient energy utilization and energy saving.

[0053] A second aspect of the present invention provides a temperature control device for a gas storage reservoir, the parameters of which are determined using the parameter determination method for the temperature control device for a gas storage reservoir described above.

[0054] The structure of the gas storage in the embodiment of the present invention is as follows Figure 2 As shown, it includes an air storage chamber and a plug 5, wherein a sealing door 4 is provided between the plug 5 and the air storage chamber.

[0055] The inner wall of the gas storage chamber is provided with a sealing layer 3 and a lining layer 2 from the inside to the outside, wherein the lining layer 2 is a reinforced concrete structure.

[0056] The heat exchange tube in the temperature control device of the embodiment of the present invention comprises a heat exchange inlet tube 1 and a heat exchange outlet tube 6; the heat exchange inlet tube 1 is a spiral structure, which is wound in the lining layer 2 of the gas storage reservoir along the axial direction of the gas storage reservoir, the inlet of the heat exchange inlet tube 1 extends out of the lining layer 2, and an inlet valve 7, an inlet flow meter and an inlet thermometer 9 are arranged on the extended end; the heat exchange outlet tube 6 is pre-buried in the lining layer 2, one end of which is connected to the outlet of the heat exchange inlet tube 1, and the other end extends out of the lining layer 2, and an outlet valve 8, an outlet flow meter and an outlet thermometer 10 are arranged on the extended end.

[0057] The temperature control device for a gas storage reservoir of the present invention can take away excess heat when the gas storage reservoir is inflated, and replenish heat into the gas storage reservoir when the gas storage reservoir is deflated, thereby making the temperature of the gas storage reservoir relatively stable, reducing the impact of temperature load on the lining structure, and improving the reliability and service life of the gas storage reservoir. At the same time, there is no need to adjust the inflation or deflation process according to the temperature of the gas storage reservoir as in the prior art. Therefore, the efficiency of inflation and deflation can be guaranteed, so that the gas storage reservoir can operate normally.

[0058] The embodiment of the present invention defines that the ratio of the thickness of the lining layer 2 to the distance between the heat exchange inlet pipe 1 and the inner surface of the lining layer 2 is 1:0.3~0.4, and the pitch L0 of the spiral structure is 1m~2m and is greater than or equal to a preset multiple of the thickness of the lining layer 2, and the preset multiple can be 1.5 times~2.5 times, preferably 2 times. The pitch of the spiral heat exchange inlet pipe 1 of the present invention and the relative position design with the lining contribute to the uniform distribution of heat in the gas storage reservoir, making the cooling or heating effect more uniform and avoiding local overheating or overcooling.

[0059] In order to ensure the stability of the heat exchange tube, the embodiment of the present invention pre-buries anchor steel rings around the tube, and the steel rings are firmly welded to the lining steel bars to form an overall force-bearing structure to limit the displacement of the heat exchange tube. In this way, the safety and service life of the water pipe can be taken into account while ensuring the temperature control effect, and the spacing of the heat exchange tubes can be increased at the sudden change of the gas storage body.

[0060] Relying on interdisciplinary theoretical support such as thermodynamics, fluid mechanics, material mechanics and structural engineering, the present invention has carefully constructed a set of comprehensive and refined gas storage temperature control devices and parameter determination methods, laying a solid foundation for the long-term and reliable operation of compressed air energy storage power stations.

[0061] The above are only several embodiments of the present invention and are not intended to limit the present invention in any form. Although the present invention is disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Any technician familiar with the profession, without departing from the scope of the technical solution of the present invention, using the above disclosed technical content to make slight changes or modifications are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A method for determining parameters of a temperature control device for a gas storage, characterized in that: include: Obtaining the temperature difference between the inlet and outlet of the heat exchange tube in the temperature control device and determining the difference in gas internal energy before and after the gas storage is filled, wherein the temperature control device is arranged in the lining layer of the gas storage; Determining the flow diameter of the heat exchange tube according to the temperature difference and the gas internal energy difference; The minimum wall thickness of the heat exchange tube is determined according to the flow diameter of the heat exchange tube, the allowable stress, and the maximum pressure that the heat exchange tube can withstand.

2. The method for determining parameters of a temperature control device for a gas storage according to claim 1, characterized in that: Determine the difference in gas internal energy before and after the gas storage is filled, including: Determine the inflation correction coefficient according to the inflation parameters of the gas storage reservoir; The difference in gas internal energy before and after the gas storage reservoir is filled is determined based on the filling correction coefficient and the temperature of the gas storage reservoir before and after the filling.

3. The method for determining parameters of a temperature control device for a gas storage according to claim 2, characterized in that: The inflation parameters include at least one of inflation speed, inflation pressure, inflation time and constant volume specific heat capacity.

4. The method for determining parameters of a temperature control device for a gas storage according to claim 2, characterized in that: Determining the gas internal energy difference before and after the gas storage is filled with gas according to the inflation correction coefficient and the temperature of the gas storage before and after the gas storage is filled with gas, specifically includes: Determining the gas internal energy of the gas storage before filling according to the product of the temperature of the gas storage before filling and the filling correction coefficient; Determining the gas internal energy of the gas storage after the gas storage is inflated according to the product of the temperature of the gas storage after the gas storage is inflated and the inflation correction coefficient; The difference between the internal energy of the gas after the gas storage reservoir is filled with gas and the internal energy of the gas before the gas storage reservoir is filled with gas is determined to obtain the gas internal energy difference.

5. The method for determining parameters of a temperature control device for a gas storage according to claim 1, characterized in that: Determining the flow diameter of the heat exchange tube according to the temperature difference and the gas internal energy difference specifically includes: Determining the volume flow rate of the heat exchange tube according to the temperature difference and the gas internal energy difference; The flow diameter is determined according to the volume flow rate and the flow velocity of the heat exchange medium in the heat exchange tube.

6. The method for determining parameters of a temperature control device for a gas storage according to claim 5, characterized in that: Determining the volume flow rate of the heat exchange tube according to the temperature difference and the gas internal energy difference specifically includes: Determining the mass flow rate of the heat exchange tube according to the temperature difference and the gas internal energy difference; The volume flow rate of the heat exchange tube is determined according to the mass flow rate and the density of the heat exchange medium.

7. The method for determining parameters of a temperature control device for a gas storage according to claim 1, characterized in that: The minimum wall thickness of the heat exchange tube is determined according to the flow diameter, allowable stress and maximum pressure of the heat exchange tube, specifically including: Determine the product of the flow diameter of the heat exchange tube and the maximum pressure that the heat exchange tube can withstand; The minimum wall thickness of the heat exchange tube is determined according to the quotient of the product and the allowable stress.

8. A temperature control device for a gas storage, wherein the parameters of the temperature control device are determined by the method for determining the parameters of the temperature control device for a gas storage according to any one of claims 1 to 7, characterized in that: The heat exchange tube includes a heat exchange inlet tube and a heat exchange outlet tube; The heat exchange inlet pipe is a spiral structure, which is wound in the lining layer of the gas storage reservoir along the axial direction of the gas storage reservoir, and the inlet of the heat exchange inlet pipe extends out of the lining layer; The heat exchange outlet pipe is pre-buried in the lining layer, one end of which is connected to the outlet of the heat exchange inlet pipe, and the other end extends out of the lining layer.

9. The temperature control device for a gas storage according to claim 8, characterized in that: The ratio of the thickness of the lining layer to the distance between the heat exchange inlet pipe and the inner surface of the lining layer is 1:0.3-0.

4.

10. The temperature control device for a gas storage according to claim 8, characterized in that: The pitch of the spiral structure is 1m-2m and is greater than or equal to a preset multiple of the thickness of the lining layer.

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