Non-condensable gas reduction system

Abstract

In a system for reducing non-condensable gases, this technology provides a mechanism for maintaining an environment that facilitates the dissolution of the non-condensable gas to be dissolved. [Solution] A non-condensable gas reduction system for returning non-condensable gas from a geothermal power plant to an injection well, comprising: a pump for pressurizing a first liquid sent to the injection well; a compressor for pressurizing non-condensable gas discharged from a condenser; a mixing unit for mixing the first liquid and the non-condensable gas discharged from the compressor and discharging the mixed fluid; a pressure regulating valve for adjusting the pressure of the mixed fluid; a first flow meter for measuring the flow rate of the first liquid; a second flow meter for measuring the flow rate of non-condensable gas supplied to the mixing unit; a thermometer for measuring the temperature of the mixed fluid; a pressure meter for measuring the pressure of the mixed fluid; a recycling line for recycling gases contained in the mixed fluid on the suction side of the compressor; and a control device, wherein the control device monitors the dissolution state of the non-condensable gas in the mixed fluid and controls the gas-liquid ratio and pressure based on the degree of supersaturation of the target gas to be dissolved contained in the non-condensable gas.

Description

Technical Field

[0001] The present disclosure relates to a non-condensable gas reduction system.

Background Art

[0002] Patent Document 1 discloses a method for disposing of non-condensable gas generated in a geothermal power generation facility, in which the non-condensable gas generated in a condenser provided downstream of a steam turbine is injected into a reduction well for hot water reduction, and is reduced underground together with the reduction hot water.

[0003] Patent Document 2 discloses a geothermal power generation plant including a reduction water flow path for transporting reduction water to a reduction well, a gas extraction device for extracting gas from a condenser, and a gas flow path for supplying the gas extracted from the condenser to the reduction water flow path and mixing it into the reduction water.

[0004] Patent Document 3 discloses a non-condensable gas reduction system used in a so-called binary geothermal power plant, in which non-condensable gas remaining uncondensed in an evaporator is sent to a reduction well.

[0005] Patent Document 4 discloses a non-condensable gas reduction system used in a so-called flash geothermal power plant, in which non-condensable gas remaining uncondensed in a condenser is sent to a reduction well. Each of Patent Document 3 and Patent Document 4 discloses that the non-condensable gas reduction system includes an ejector that attracts non-condensable gas and discharges a liquid mixed with a pressurized liquid, and returns the liquid discharged by the ejector to the reduction well, thereby returning the non-condensable gas to the reduction well.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

[0007] As disclosed in Patent Documents 1 and 2, it has been proposed that non-condensable gases such as carbon dioxide or hydrogen sulfide be returned to a reinjection well along with reinjecting hot water in geothermal power generation. For example, when returning non-condensable gases to a reinjection well, there is a need to return them efficiently to the reinjection well. For example, in the non-condensable gas reduction systems disclosed in Patent Documents 3 and 4, respectively, it is disclosed that non-condensable gases are returned to a reinjection well by an ejector.

[0008] When reducing a non-condensable gas by dissolving it in a solution, it is necessary to sufficiently dissolve the non-condensable gas in the solution.

[0009] This disclosure provides a technology for maintaining an environment in which non-condensable gases are easily dissolved in a solution in a system for reducing non-condensable gases. [Means for solving the problem]

[0010] This disclosure provides a non-condensable gas reduction system for a geothermal power plant, in which non-condensable gas that remains uncondensed when cooled in a condenser in a first gas contained in geothermal fluid that springs from a production well is returned to a reinjection well, comprising: a pump for pressurizing a first liquid sent to the reinjection well; a compressor for pressurizing the non-condensable gas discharged from the condenser; a mixing unit for mixing the first liquid and the non-condensable gas discharged from the compressor and discharging a mixed fluid; a pressure regulating valve for adjusting the pressure of the mixed fluid; a first flow meter for measuring the flow rate of the first liquid; a second flow meter for measuring the flow rate of the non-condensable gas supplied to the mixing unit; a thermometer for measuring the temperature of the mixed fluid; a pressure meter for measuring the pressure of the mixed fluid; a recycling line for recycling the gas contained in the mixed fluid on the suction side of the compressor; and a control device, wherein the control device monitors the dissolution state of the non-condensable gas in the mixed fluid and controls the gas-liquid ratio and pressure based on the degree of supersaturation of the target gas to be dissolved contained in the non-condensable gas, providing a non-condensable gas reduction system. [Effects of the Invention]

[0011] According to this disclosure, an environment can be maintained in which the non-condensable gas to be dissolved is easily dissolved. [Brief explanation of the drawing]

[0012] [Figure 1] Figure 1 is a schematic diagram showing the configuration of a geothermal power plant equipped with a non-condensable gas reduction system according to this embodiment. [Figure 2] Figure 2 is a schematic diagram showing the configuration of the non-condensable gas reduction system according to this embodiment. [Figure 3] Figure 3 illustrates the process performed by the control device of the non-condensable gas reduction system according to this embodiment. [Modes for carrying out the invention]

[0013] The embodiments will be described below with reference to the attached drawings. However, this disclosure is not limited to these examples and is intended to include all modifications within the meaning and scope of the claims as indicated by the claims.

[0014] In addition, regarding the descriptions and drawings of each embodiment, components having substantially the same or corresponding functional configurations may be denoted by the same reference numerals, thereby omitting redundant explanations. Furthermore, for ease of understanding, the scale of each part in the drawings may differ from that of the actual parts.

[0015] A non-condensable gas reduction system according to an embodiment of this disclosure will now be described. The non-condensable gas reduction system according to an embodiment of this disclosure is a system in a geothermal power plant that returns non-condensable gas, which remains uncondensed when cooled in the condenser, to the injection well, from the first gas contained in the geothermal fluid that springs from the production well. The non-condensable gas reduction system according to an embodiment of this disclosure comprises a pump that pressurizes the first liquid sent to the injection well, a compressor that pressurizes the non-condensable gas discharged from the condenser, and a mixing unit that mixes the first liquid and the non-condensable gas discharged from the compressor and discharges the mixed fluid. Furthermore, the non-condensable gas reduction system according to an embodiment of this disclosure comprises a pressure control valve that adjusts the pressure of the mixed fluid, a first flow meter that measures the flow rate of the first liquid, a second flow meter that measures the flow rate of the non-condensable gas supplied to the mixing unit, and a thermometer that measures the temperature of the mixed fluid. In addition, the non-condensable gas reduction system according to an embodiment of this disclosure comprises a pressure gauge that measures the pressure of the mixed fluid, a recycling line that recycles the gas contained in the mixed fluid on the suction side of the compressor, and a control device. Furthermore, the control device in the non-condensable gas reduction system according to the embodiment of this disclosure monitors the dissolution state of the non-condensable gas in the mixed fluid and controls the gas-liquid ratio and pressure based on the degree of supersaturation of the target gas to be dissolved contained in the non-condensable gas.

[0016] As a non-condensable gas (NCG: Non-Condensable Gas) underground reduction system for a geothermal power plant, a non-condensable underground reduction system is disclosed that attracts and dissolves non-condensable gas by an ejector driven by reduced water (reduced hot water, cooling surplus water, reduced pit stored water, etc.) without discharging it into the atmosphere through improvements in the configuration and structure of above-ground equipment (for example, Patent Document 3, Patent Document 4, etc.).

[0017] In geothermal power generation, when non-condensable gases such as carbon dioxide and hydrogen sulfide are contained in steam, non-condensable gas accumulates in the upper part of the condenser directly below the turbine. When non-condensable gas accumulates in the upper part of the condenser directly below the turbine, the degree of vacuum decreases. To prevent the decrease in the degree of vacuum, the non-condensable gas accumulated in the upper part of the condenser directly below the turbine is removed by a gas extractor or the like. Currently, generally, it is sent from the condenser to the cooling tower, mixed with air, and discharged into the atmosphere.

[0018] In geothermal power generation, although much less than power generation by other renewable energies, carbon dioxide is mainly discharged as a non-condensable gas. For example, about 90% of the non-condensable gas is carbon dioxide.

[0019] Overseas, for example, in New Zealand, a carbon tax is already imposed on carbon dioxide discharged from geothermal power generation. In the future, there is a possibility that the cost of geothermal power generation will also increase in Japan.

[0020] Although a method of reducing non-condensable gas underground is shown, specific operating conditions and control methods are not shown.

[0021] The non-condensable gas reduction system according to this embodiment constantly measures the flow rate of non-condensable gas, the flow rate of water to be dissolved, the temperature and pressure of non-condensable gas dissolved water, and performs dissolution failure detection (condition monitoring) based on the supersaturation degree of the gas to be dissolved contained in the non-condensable gas. In the non-condensable gas reduction system according to this embodiment, the composition of the non-condensable gas uses a value analyzed in advance. Further, the non-condensable gas reduction system according to this embodiment optimally maintains the gas-liquid ratio and pressure, and maintains an environment (concentration difference at the gas-liquid interface) where dissolution is easy.

[0022] The non-condensable gas reduction system according to this embodiment can stably dissolve non-condensable gases and return them underground in response to changes in plant operation. Therefore, by applying the non-condensable gas reduction system according to this embodiment, geothermal power generation facilities can be operated while avoiding the carbon tax that has already been implemented overseas.

[0023] Furthermore, the non-condensable gas reduction system according to the disclosed embodiment can be applied in common to non-condensable gas underground reduction systems in geothermal power plants of the so-called flash type and binary type.

[0024] The non-condensable gas reduction system according to this embodiment will be described in detail with reference to the drawings. Figure 1 is a schematic diagram of the configuration of a geothermal power plant 1 equipped with a non-condensable gas reduction system 50, which is an example of a non-condensable gas reduction system according to this embodiment.

[0025] Geothermal power plant 1 comprises a gas-liquid separator 10, a power generation unit 20, a condenser 30, a cooling unit 40, a non-condensable gas reduction system 50, and a control unit 60. Geothermal power plant 1 is a so-called flash-type geothermal power plant. Geothermal power plant 1 also comprises valves 81 and 82 and a pump 91.

[0026] [Gas-liquid separator 10] The gas-liquid separator 10 separates the geothermal fluid GF ejected from the production well PWL into steam ST and hot water HW. The geothermal fluid GF ejected from the production well PWL is either allowed to flow or blocked by the valve 81. The steam ST discharged from the gas-liquid separator 10 is sent to the power generation unit 20. The hot water HW discharged from the gas-liquid separator 10 is discharged into the reinjection well RWL. The pressure gauge 71, described later, measures the pressure of the hot water HW.

[0027] Here, steam ST is not pure water vapor, but includes gases emitted from the production well PWL, such as carbon dioxide and hydrogen sulfide.

[0028] [Power generation unit 20] The power generation unit 20 generates electricity using steam ST. The power generation unit 20 comprises a turbine 21 and a generator 22. The turbine 21 is rotated by the steam ST. More specifically, the turbine 21 rotates due to the pressure difference between the pressure from the steam ST and the pressure reduced by the condensation of water vapor contained in the steam ST in the condenser 30. The generator 22 is connected to the turbine 21. When the turbine 21 rotates, the rotating shaft of the generator 22 rotates and generates electricity. The electricity generated by the generator 22 is supplied to the outside.

[0029] [Condenser 30] The condenser 30 cools the steam ST discharged from the turbine 21 with coolant CW, more specifically coolant CW1, supplied from the cooling unit 40. The condenser 30 is a so-called surface contact condenser. The condenser 30 performs heat exchange between the coolant CW1 and the steam ST. By performing heat exchange between the coolant CW1 and the steam ST, the steam ST is cooled. As the steam ST is cooled in the condenser 30, it condenses into water. In the surface contact condenser 30, for example, the coolant CW1 cools the steam ST by flowing inside the piping of the heat exchanger, and the coolant CW1 does not come into direct contact with the steam ST. The water condensed from the steam ST is discharged outside the condenser (not shown). Alternatively, a direct contact condenser, in which the coolant comes into contact with the steam, may be used as the condenser 30. In a direct contact condenser, the water condensed from the steam ST is sent to the cooling unit together with the coolant.

[0030] Non-condensable gases (NCGs) such as carbon dioxide and hydrogen sulfide contained in the steam ST accumulate at the top of the condenser 30. When non-condensable gases NCG accumulate, the pressure in the condenser 30 increases. When the pressure in the condenser 30 increases, the driving force for rotating the turbine 21 decreases. When the driving force for rotating the turbine 21 decreases, the power generation efficiency of the power generation unit 20 decreases. Therefore, it is desirable to discharge the non-condensable gases NCG accumulated in the condenser 30 from the condenser 30.

[0031] In geothermal power plant 1, the non-condensable gas (NCG) that accumulates in the condenser 30 is drawn in by the non-condensable gas reduction system 50 and discharged into the reinjection well (RWL).

[0032] [Cooling section 40] The cooling unit 40 supplies coolant CW to cool the steam ST in the condenser 30. The cooling unit 40 is, for example, a cooling tower. The coolant CW1 cooled in the cooling unit 40 is sent to the condenser 30 by the pump 91. In the condenser 30, the coolant CW2 whose temperature has risen due to heat exchange with the steam ST returns to the cooling unit 40 to be cooled.

[0033] [Non-condensable gas reduction system 50] The non-condensable gas reduction system 50 will now be described. Figure 2 is a schematic diagram of the configuration of the non-condensable gas reduction system 50, which is an example of the non-condensable gas reduction system according to this embodiment.

[0034] The non-condensable gas reduction system 50 induces and discharges non-condensable gas (NCG) from the condenser 30. The non-condensable gas reduction system 50 includes a gas-liquid separator 51, a mixing unit 54, a control device 58, pressure gauges 71 and 74, a thermometer 75, flow meters 76 and 77, valves 83 and 84, and a primary pressure regulating valve 86. The non-condensable gas reduction system 50 also includes a pump 55, a compressor 56, and a check valve 57.

[0035] The non-condensable gas reduction system 50 is equipped with a check valve 57 upstream of the compressor 56 and valve 83. The check valve 57 prevents coolant CWa and hot water HW from flowing back into the condenser 30.

[0036] The mixing unit 54 mixes the coolant CW, more specifically the coolant CWa which is a part of the coolant CW1, with the non-condensable gas NCG and discharges the mixed liquid MW. The mixing unit 54 is, for example, an ejector, a static mixer, or a tank. According to the non-condensable gas reduction system 50, the dissolved state can be easily maintained when an ejector, a static mixer, or a tank is used as the mixing unit.

[0037] Pump 55 pressurizes and supplies the coolant CWa, which is the liquid to be dissolved, to the mixing unit 54. Pump 55 is, for example, an axial flow pump.

[0038] The compressor 56 pressurizes and supplies the non-condensable gas (NCG) discharged from the condenser 30 to the mixing unit 54.

[0039] Pressure gauge 71 measures the pressure of the hot water HW discharged from the gas-liquid separator 10. Pressure gauge 74 measures the pressure of the mixed liquid MW discharged from the mixing section 54. Thermometer 75 measures the pressure of the mixed liquid MW discharged from the mixing section 54.

[0040] Flow meter 76 measures the flow rate of non-condensable gas (NCG) discharged from condenser 30. Flow meter 77 measures the flow rate of coolant (CWa) discharged from pump 55.

[0041] Each of the flow meters 76 and 77 is, for example, a differential pressure flow meter, a vortex flow meter, an ultrasonic flow meter, a wet gas meter, or a dry gas meter.

[0042] Valve 83 is installed in the flow path of non-condensable gas NCG between the condenser 30 and the mixing section 54. Valve 84 is installed in the recycle line that returns from the gas-liquid separator 51 to the upstream of the compressor 56. Valve 84 is a flow control valve. By installing the recycle line, the non-condensable gas NCG that could not be dissolved can be dissolved.

[0043] The primary pressure regulating valve 86 controls the pressure so that the back pressure downstream of the mixing section 54 becomes the desired back pressure.

[0044] (Control device 58) The control device 58 is primarily composed of a computer, including, for example, a processor, memory or other storage devices, auxiliary storage devices, and an external input / output interface device. The processor is, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), or an MPU (Micro Processing Unit). The control device 58 may also be, for example, a programmable logic controller (PLC).

[0045] For example, the control device 58 includes composition data 58d as a database stored in the storage device. The control device 58 also includes characteristic data 58s as a database stored in the storage device. The characteristic data 58s shows, for example, the solubility SL of a gas contained in a non-condensable gas NCG at a predetermined pressure (P), temperature, and density. For example, lines L1, L2, and L3 show the solubility SL at a predetermined density and pressure P. Note that lines L1, L2, and L3 have different temperatures. For example, lines L1, L2, and L3 are arranged in descending order of temperature.

[0046] The processing of the control device 58 will now be described. Figure 3 is a diagram illustrating the processing performed by the control device 58 of a noncondensable gas reduction system 50, which is an example of a noncondensable gas reduction system according to this embodiment.

[0047] The control device 58 determines the dissolution state of the non-condensable gas NCG by directly analyzing it, or by calculating the degree of supersaturation based on the gas-liquid ratio, temperature, pressure, and target dissolution amount. The control device 58 can easily determine the dissolution state of the non-condensable gas NCG by directly analyzing it, or by calculating the degree of supersaturation based on the gas-liquid ratio, temperature, pressure, and target dissolution amount.

[0048] First, the control device 58 controls the system to set a dissolution target. Specifically, for example, the control device 58 reads a set value and sets the dissolution target. Hereafter, let's call the dissolution target A. Dissolution target A is, for example, the volumetric solubility.

[0049] [Calculation of basic characteristics (Processing ProcM)] The control device 58 calculates pressure characteristics from temperature measurements taken by the thermometer 75 by executing the process ProcM. Specifically, it calculates the pressure of the non-condensable gas NCG from the temperature measurements using selected basic characteristics. Basic characteristics are data indicating the solubility of the gas to be dissolved at pressure, temperature, and concentration. Basic characteristics can be determined, for example, from Henry's Law. Alternatively, a database of basic characteristics may be constructed experimentally.

[0050] The control device 58 calculates the volume ratio of a specific gas, such as carbon dioxide, contained in the noncondensable gas NCG from the composition data of the noncondensable gas NCG.

[0051] The control device 58 then corrects the basic characteristics described above for specific gases contained in the non-condensable gas NCG, such as carbon dioxide and its partial pressure.

[0052] Furthermore, the control device 58 calculates the correlation between the gas-liquid ratio and the theoretical dissolution amount from the composition and density of the non-condensable gas NCG. In particular, the control device 58 calculates the correlation between the gas-liquid ratio and the theoretical dissolution amount for a specific gas contained in the non-condensable gas NCG, such as carbon dioxide.

[0053] The control device 58 obtains the flow rate (G) of the non-condensable gas NCG from a flow meter 76, which is a gas flow meter that measures the flow rate of the non-condensable gas NCG. The control device 58 also obtains the flow rate (L) of the coolant CWa, which is the liquid to be dissolved, from a flow meter 77, which is a liquid flow meter that measures the flow rate of the coolant CWa.

[0054] The control device 58 then calculates the gas-liquid ratio (=G / L). The gas-liquid ratio is determined by the volume ratio of the gas volume to the liquid volume. The control device 58 also calculates the theoretical solubility (B) from the correlation between the gas-liquid ratio and the theoretical solubility.

[0055] [Detection of dissolution failure (condition monitoring) (Processing ProcA)] The control device 58 calculates the theoretical supersaturation X (=BA). Then, the control device 58 compares the recommended supersaturation (Y) with the theoretical supersaturation to detect solubility deficiency. If the theoretical supersaturation X is equal to or greater than the recommended supersaturation (Y), the control device 58 determines that there is sufficient supersaturation and executes process ProcB. If the theoretical supersaturation X is less than the recommended supersaturation (Y), the control device 58 determines that there is insufficient supersaturation.

[0056] The following describes the processing performed by the control device 58 based on the degree of supersaturation.

[0057] [Minimizing the amount of recycled material (Processing ProcB)] If the theoretical supersaturation (X) is equal to or greater than the recommended supersaturation (Y), there is considered to be sufficient dissolution capacity. Therefore, the flow rate of the coolant CWa, which is the liquid to be dissolved, is increased to reduce the amount of recycled gas.

[0058] Specifically, the control device 58 calculates the optimal gas-liquid ratio, converts the optimal gas-liquid ratio into a liquid flow rate, and uses PID control to control the output of the liquid transfer pump 55. The control device 58 also controls the flow rate of the non-condensable gas NCG flowing through the recycling line using a flow control valve 84.

[0059] [Decrease in the flow rate of the solution to be dissolved (Processing ProcC)] In process ProcA, if the theoretical supersaturation X is less than the recommended supersaturation (Y), the control device 58 determines whether the compressor output is less than 100%. If the compressor output is not less than 100%, in other words, 100% or more, the control device 58 determines that the compressor has no reserve capacity. In the above example, the control device determines whether the compressor output is less than 100%, but the threshold can be set appropriately within a range that does not overload the compressor.

[0060] Furthermore, if the compressor output is not less than 100%, in other words, if it is 100% or more, the control device 58 reduces the operating output of the liquid transfer pump to decrease the liquid flow rate.

[0061] Specifically, the control device 58 calculates the optimal gas-liquid ratio, converts the optimal gas-liquid ratio into a liquid flow rate, and uses PID control to control the output of the liquid transfer pump 55.

[0062] [Increase in gas flow rate (processing ProcD)] In process ProcA, if the theoretical supersaturation X is less than the recommended supersaturation (Y), the control device 58 determines whether the compressor output is less than 100%. If the compressor output is less than 100%, the control device 58 determines that the compressor has reserve capacity.

[0063] Furthermore, if the compressor output is less than 100%, the control device 58 increases the operating output of the compressor to increase the gas volume.

[0064] Specifically, the control device 58 calculates the optimal gas-liquid ratio, converts the optimal gas-liquid ratio into a gas flow rate, and performs PID control on the output of the compressor 56. If the PID control value (MV) is 100% or higher, the determination is made again. If the PID control value (MV) is less than 100%, the control continues.

[0065] [Constant back pressure (Processing ProcE)] The non-condensable gas reduction system 50 uses a primary pressure regulating valve 86 to adjust the back pressure downstream of the mixing section 54 to maintain it at a desired pressure.

[0066] In process ProcA, the control device 58 determines the dissolution pressure based on the results of correcting for specific gases contained in the non-condensable gas NCG, such as carbon dioxide, and their partial pressures, regarding the basic characteristics. Then, the control device 58 controls the primary pressure regulating valve 86 to achieve the determined dissolution pressure.

[0067] As described above, for example, the control device 58 determines a target control pressure that reflects the partial pressure of carbon dioxide contained in the non-condensable gas NCG based on the pressure characteristics of the solubility of carbon dioxide contained in the non-condensable gas NCG, which are determined by Henry's Law, and controls the pressure. The control device 58 can accurately control the pressure by controlling it based on the pressure characteristics of the solubility of carbon dioxide contained in the non-condensable gas NCG, which are determined by Henry's Law.

[0068] The control device 58 controls the flow rate of the pump 55 and the compressor 56 so that the difference between the theoretical dissolution amount at each pressure, determined from the gas composition contained in the non-condensable gas NCG, and the system's target dissolution amount is greater than or equal to a predetermined value. By controlling the flow rate of the pump 55 and the compressor 56 so that the difference between the theoretical dissolution amount at each pressure, determined from the gas composition contained in the non-condensable gas NCG, and the system's target dissolution amount is greater than or equal to a predetermined value, the gas-liquid ratio can be maintained at an appropriate state, and the dissolution state can be maintained.

[0069] According to the non-condensable gas reduction system of this embodiment, in a system for reducing non-condensable gases, it is possible to maintain an environment in which the non-condensable gas to be dissolved is easily dissolved.

[0070] The embodiments disclosed herein should be considered in all respects as illustrative and not restrictive. The above embodiments may be omitted, replaced, or modified in various ways without departing from the scope and spirit of the appended claims. [Explanation of Symbols]

[0071] 1. Geothermal power plant 10, 51 Gas-liquid separator 20 Power Generation Department 30 Condenser 40 Cooling section 50 Non-condensable gas reduction system 54 Mixing section 55, 91 pumps 56 Compressor 57 Check valve 58 Control device 60 Control Unit 71, 74 Pressure gauge 75 Thermometer 76, 77 Flowmeter 81, 82, 83, 84 valves 86 Primary pressure regulating valve CW, CW1, CW2, CWa Coolant GF geothermal fluid HW hot water MW mixture NCG (Non-condensable gas) PWL production well RWL Reinforcement Well ST Steam

Claims

1. In a geothermal power plant, a non-condensable gas reduction system returns the non-condensable gas that remains after cooling in the condenser in the first gas contained in the geothermal fluid that springs from the production well back to the reinjection well. A pump for pressurizing the first liquid sent to the injection well, A compressor for pressurizing the non-condensable gas discharged from the condenser, A mixing unit that mixes the aforementioned first liquid with the non-condensable gas discharged from the compressor and discharges the mixed fluid, A pressure regulating valve for adjusting the pressure of the mixed fluid, A first flow meter for measuring the flow rate of the first liquid, A second flow meter for measuring the flow rate of the non-condensable gas supplied to the mixing section, A thermometer for measuring the temperature of the mixed fluid, A pressure gauge for measuring the pressure of the mixed fluid, A recycling line for recycling the gas contained in the mixed fluid is provided on the suction side of the compressor. Control device and Equipped with, The control device monitors the dissolution state of the non-condensable gas in the mixed fluid and controls the gas-liquid ratio and pressure based on the degree of supersaturation of the target gas contained in the non-condensable gas. Non-condensable gas reduction system.

2. The control device determines the dissolution state of the noncondensable gas by directly analyzing it, or by calculating the degree of supersaturation based on the gas-liquid ratio, temperature, pressure, and target dissolution amount. The non-condensable gas reduction system according to claim 1.

3. The mixing unit is either an ejector, a static mixer, or a tank. The non-condensable gas reduction system according to claim 1.

4. The second flow meter is one of the following: a differential pressure flow meter, a vortex flow meter, an ultrasonic flow meter, a wet gas meter, or a dry gas meter. The non-condensable gas reduction system according to claim 1.

5. The control device determines a target control pressure that reflects the partial pressure of carbon dioxide contained in the noncondensable gas, based on the pressure characteristics of the solubility of carbon dioxide contained in the noncondensable gas determined by Henry's Law, and controls the pressure accordingly. The non-condensable gas reduction system according to claim 1.

6. The control device controls the flow rate of the pump and the flow rate of the compressor so that the difference between the theoretical dissolution amount at each pressure, determined from the composition of the gas contained in the noncondensable gas, and the system's target dissolution amount is greater than or equal to a predetermined value. The non-condensable gas reduction system according to claim 1.

7. The recycling line is equipped with a flow control valve, and the control device controls the flow rate of the gas flowing through the recycling line using the flow control valve. The non-condensable gas reduction system according to claim 1.

Images