A direct condensing geothermal fluid vapor-liquid ratio measurement system

Abstract

The utility model belongs to the technical field of energy engineering, concretely relates to the proportional measurement of geothermal fluid. A kind of direct condensing geothermal fluid vapor-liquid proportional measurement system, including main output pipe, condensing unit, separation unit, cooling water unit, measurement unit;Condensing unit includes the direct condensing condenser for receiving heat source fluid;Cooling water unit is used to output cooling water to direct condensing condenser;Separation unit includes gas-liquid separator;Gas-liquid separator includes the gas phase output pipe for outputting gas and the liquid phase output pipe for outputting liquid, and the liquid phase output pipe is connected with measurement tank;Heat source fluid and cooling water are directly mixed and heat exchanged in the direct condensing condenser, and the obtained mixed fluid is output to gas-liquid separator.The utility model provides the system and method using direct condensing method, and the original proportion of water, steam and incondensable gas in wellhead geothermal fluid can be accurately measured.

Description

Technical Field

[0001] This utility model belongs to the field of energy engineering technology, specifically relating to the proportional measurement of geothermal fluids. Background Technology

[0002] Geothermal resources are characterized by large reserves, wide distribution, stability and reliability, and high utilization rate, and have become a key focus of current new energy development. They are now mostly used in geothermal heating and geothermal power generation. However, the performance of geothermal power generation is greatly affected by the gas-liquid ratio of geothermal fluid in the production well.

[0003] The geothermal fluid produced at the wellhead of a geothermal production well is typically a two-phase gas-liquid mixture composed of non-condensable gases, water vapor, and geothermal water. The content of geothermal water affects its flow within the pipes; higher geothermal water content results in greater flow resistance and heat loss. The heat used for geothermal power generation primarily comes from the heat carried by the water vapor in the geothermal fluid, influencing the well's production efficiency and the generator set design. The content of non-condensable gases significantly impacts the performance of the heat exchanger and the design of the generator set's exhaust system. Furthermore, the thermodynamic and thermal properties of geothermal water, water vapor, and non-condensable gases differ considerably. If the proportions of each component in the geothermal fluid produced at the wellhead cannot be determined, directly using it as a heat source for power generation will affect the generator set's safety and power generation performance.

[0004] To address the aforementioned technical challenges, the industry has proposed a method of flash-separating and then condensing the geothermal fluid at the wellhead. The proportions of each component are determined by monitoring the temperature, pressure, and flow rate at the wellhead, after the gas-liquid separator, and after condensation. For example, document CN112031751B discloses a bypass-type gas-liquid separation geothermal production capacity testing system, including a production well, wellhead valves, a gas-liquid separator, a condenser, a cooling tower, a cooling pump, a booster pump, and a reinjection well. One heat source outlet of the production well is connected to the inlet of the gas-liquid separator, and the other outlet is connected to the reinjection well. The liquid outlet of the gas-liquid separator is connected to the inlet of the booster pump. The gas outlet of the gas-liquid separator is connected to the inlet of the condenser. The gas outlet of the condenser is connected to the atmosphere. The condensate outlet of the condenser is connected to the inlet of the cooling tower. The outlet of the cooling tower is connected to the inlet of the cooling pump. The outlet of the cooling pump is connected to the condensate inlet of the condenser. The liquid outlet of the condenser is connected to the inlet of the booster pump. The outlet of the booster pump is connected to the reinjection well.

[0005] However, the "flash separation followed by condensation" method destroys the original properties of the fluid, i.e., its chemical composition. After flash evaporation, the fluid is permanently separated into gas and liquid phases with different chemical compositions. This process destroys and redistributes the original material composition of the fluid. Some of the original water is directly converted into gas during flash evaporation, and this change is irreversible. Therefore, it is impossible to calculate the proportion of original water that has been converted into gas. Thus, the ultimate goal of this method is to obtain the two separated fluids for use (such as power generation and utilization), rather than to accurately measure the chemical composition of the original fluid. Utility Model Content

[0006] To address the aforementioned problems, the purpose of this invention is to provide a direct condensation geothermal fluid vapor-liquid ratio measurement system, aiming to accurately measure the original ratio of water, steam, and non-condensable gases in the geothermal fluid at the wellhead using the direct condensation method.

[0007] The specific technical solution of this utility model is as follows: A direct condensing geothermal fluid vapor-liquid ratio measurement system includes a main output pipe, a condensation unit, a separation unit, a cooling water unit, and a measurement unit. The main output pipe outputs the heat source fluid. The condensation unit includes a direct condensing condenser for receiving the heat source fluid. The cooling water unit outputs cooling water into the direct condensing condenser. The separation unit includes a gas-liquid separator, which includes a gas phase output pipe for outputting gas and a liquid phase output pipe for outputting liquid. The liquid phase output pipe is connected to a measurement tank. The heat source fluid and cooling water are directly mixed in the direct condensing condenser. The heat exchange is combined, and the resulting mixed fluid is output to the gas-liquid separator; the measuring unit includes a first pressure measuring instrument, a first temperature measuring instrument, and a first flow meter installed at the input end of the direct condenser receiving the heat source fluid; a second temperature measuring instrument and a second flow meter installed at the input end of the direct condenser receiving cooling water; a third temperature measuring instrument installed at the output end of the direct condenser for discharging the mixed fluid; a weighing module installed at the measuring tank; and a third flow meter, a second pressure measuring instrument, and a fourth temperature measuring instrument installed at the gas phase output pipe.

[0008] Generally, direct condensation involves directly mixing the coolant with the geothermal fluid. Steam condenses instantaneously on the surface of the cooling water droplets, and the entire process is completed within a container, maintaining all components of the original fluid (water, steam, and non-condensable gases) within a single system for final separation and measurement. The entire process does not alter the fluid's overall material composition. All non-condensable gases ultimately enter the gas phase and are measured, allowing for accurate determination of the total mass of non-condensable gases in the original fluid. Furthermore, compared to indirect heat exchange condensers, it avoids the problem of non-condensable gases forming a gas film, which significantly reduces heat transfer efficiency. The heat source fluid is a two-phase mixture of non-condensable gases, water vapor, and liquid water. In a direct condenser, the heat source fluid and cooling water are mixed and exchange heat, causing water vapor to transform into a liquid phase, significantly reducing the proportion of the gas phase and overcoming the difficulty of transporting the original two-phase fluid within the system piping. The non-condensable gases remain in the gas phase and, after processing by a gas-liquid separator, can be directly separated from the liquid phase and measured separately, improving measurement accuracy. The process is simple and easy to implement. The mixed liquid phase obtained after gas-liquid separation consists only of water. The ratio of water vapor to liquid water can be determined through simple parameter detection, offering advantages such as simplicity and high accuracy. This provides a simple, low-initial-investment, and highly accurate testing platform for measuring the vapor-liquid ratio of heat source fluids.

[0009] As a further preferred embodiment of this invention, the main output pipe is further provided with a pretreatment unit for adjusting the pressure of the heat source fluid input into the direct condenser; and the adjustment pressure of the pretreatment unit is greater than the flash pressure of the heat source fluid.

[0010] Flash pressure is the absolute pressure at which the heat source fluid begins to boil and generate steam bubbles at the current temperature. It is primarily determined by the fluid's temperature and chemical composition, and is generally slightly lower than the saturated vapor pressure of pure water at that temperature. Therefore, under conservative estimates, ensuring that the pretreatment unit's regulating pressure is greater than the saturated vapor pressure of pure water at that temperature can completely suppress flash evaporation, providing a stable and controllable thermodynamic environment for subsequent equipment, especially measuring instruments, and ensuring that all subsequent measurements are performed under known and stable pressures. Although controlling the pressure alters the thermodynamic state of the heat source fluid, it does not change the fluid's overall chemical composition, which still follows the thermodynamic laws of isenthalpic processes; therefore, it can be calculated retrospectively.

[0011] As a further preferred embodiment of this invention, the pretreatment unit includes a pressure reducing valve and a back pressure valve connected in sequence. The pressure reducing valve is mainly used to withstand the fluctuating high pressure (up to tens of bar) from the main output pipe, protecting the downstream back pressure valve and precision testing instruments from the impact of drastic pressure fluctuations upstream. The back pressure valve is mainly used to control the outlet pressure (i.e., regulate the pressure) to ensure its stability at the set value.

[0012] As a further preferred embodiment of this invention, the direct condenser internally includes: a cooling water spray array at the top, and a heat source fluid distributor at the lower end of the cooling water spray array. The intended effect of the heat source fluid distributor is to uniformly spray the heat source fluid downwards, making counter-current contact with the cooling water flowing downwards, thereby enhancing the mixing efficiency.

[0013] As a further preferred embodiment of this utility model, the cooling water unit includes a condenser unit and a cooling water storage tank connected in sequence; the receiving end of the cooling water storage tank is used to receive the cooling water output by the condenser unit, and the output end of the cooling water storage tank outputs cooling water to the direct condenser.

[0014] As a further preferred embodiment of this utility model, a liquid level detector is provided inside the gas-liquid separator, and a control valve is provided on the liquid phase output pipe.

[0015] As a further preferred embodiment of this invention, a first sampling tube is provided at the gas phase output pipe. The first sampling tube can directly sample the gas phase and analyze its components, thereby helping to determine the enthalpy of the gas.

[0016] As a further preferred embodiment of this invention, a dryer is provided on the gas phase output pipe, and the dryer is located in front of the third flow meter, the second pressure measuring instrument, and the fourth temperature measuring instrument. The dryer is used to remove residual water vapor in the gas phase, thereby improving the accuracy of detection.

[0017] As a further preferred embodiment of this invention, a main valve located at the front end of the pretreatment unit is also provided on the main output pipe. The main valve is used to completely cut off the heat source fluid, facilitating the installation, maintenance, and replacement of the system. The main valve should be fully open during normal system operation.

[0018] The above system can be used in conjunction with methods for measuring the proportion of geothermal fluids, specifically including the following steps: S1. Direct Data Acquisition: The pressure P1 of the heat source fluid is acquired through the first pressure measuring instrument; the temperature T1 of the heat source fluid is acquired through the first temperature measuring instrument; and the mass flow rate M1 of the heat source fluid is acquired through the first flow meter. The temperature T2 of the cooling water is acquired through the second temperature measuring instrument; and the mass flow rate M2 of the cooling water is acquired through the second flow meter. The temperature T3 of the mixed fluid is acquired through the third temperature measuring instrument; the mass M3 of the mixed fluid is acquired through the weighing module; and the volumetric flow rate V4 of the gas is acquired through the third flow meter; the pressure P4 of the gas is acquired through the second pressure measuring instrument; and the temperature T4 of the gas is acquired through the fourth temperature measuring instrument. S2. Obtain the gas at the gas phase output pipe and perform composition analysis, and calculate the gas mass M4 and specific enthalpy h4; S3. Calculate the mass MS of water vapor in the heat source gas: MS=[M1*h1-(M3-M2) *hL-M4*h4] / (hS-hL); Where MS refers to the mass of water vapor, in kg; M1 refers to the mass of the heat source fluid, in kg; M2 refers to the mass of the cooling water, in kg; M3 refers to the mass of the mixed fluid, in kg; and M4 refers to the mass of the non-condensable gas, in kg. h1 refers to the specific enthalpy of the heat source gas under the pressure conditions before the direct condenser, in kJ / kg; hS refers to the specific enthalpy of water vapor in the heat source gas under the pressure conditions before the direct condenser, in kJ / kg; hL refers to the specific enthalpy of liquid water in the heat source gas under the pressure conditions before the direct condenser, in kJ / kg; h4 is the specific enthalpy of the non-condensable gas, in kJ / kg. S4. Calculate the mass of liquid water (ML): ML = M3 - M2 - MS; where ML refers to the mass of liquid water in the heat source fluid, in kg. S5. Calculate the mass percentage: Liquid water ratio = ML / M1 * 100%; Water vapor ratio = MS / M1 * 100%; Non-condensable gas ratio = M4 / M1 * 100%.

[0019] The derivation process of the above measurement method, especially the equation for S3, is as follows: 1. First, the core equation is: Total mass conservation: M1 = ML + MS + M4 ………………………………………(1; Liquid mass conservation: M3 = ML + MS + M2 ……………………………………(2; Thermodynamic heat conservation: E=M1*h1=ML*hL+MS*hS+M4*h4………………(3; 2. Solve by combining equations (2) and (3): From equation (2), we get: ML = M3 - M2 - MS. Substituting this into equation (3), we get: M1*h1=(M3-M2-MS)*hL+MS*hS+M4*h4, expanding and rearranging the equation, we get: MS*(hS-hL) = M1*h1-(M3-M2)*hL-M4*h4; Simplifying, we obtain the above formula: MS = [M1*h1 - (M3 - M2) *hL - M4*h4] / (hS - hL); where (hS - hL) is the latent heat of vaporization: the energy required for a unit mass of liquid to completely vaporize into a gas at a constant temperature, which can be directly known. h1 can be directly found in a table, or calculated and determined given the dryness fraction of the heat source fluid. h4 can be calculated based on the molar enthalpy of the non-condensable gas obtained from the measured molar fraction of the non-condensable gas, then by looking up the average specific heat capacity of each component gas at the inlet temperature, then calculating the molar enthalpy of the non-condensable gas, and finally dividing the molar enthalpy of the non-condensable gas by the average molar mass of the non-condensable gas.

[0020] The beneficial effects of this utility model are as follows: The measurement system established by this invention, compared with the existing technology which uses the "flash evaporation separation followed by condensation" method, directly mixes the coolant and geothermal fluid in the condenser. The entire process is completed in one container, keeping all the components of the original fluid in one system without changing the original material composition of the heat source fluid. It follows the laws of mass conservation and thermodynamic energy conservation, so only simple data needs to be detected and monitored. With the help of calculation software, more accurate and true component measurement results can be obtained.

[0021] The measurement system established by this invention only requires controlling and calculating the heat source fluid input to the direct condenser through the main output pipe and controlling and calculating the cooling water input to the direct condenser through the cooling water unit. It is easy to implement and the investment and operating costs of the equipment are within a controllable range. Attached Figure Description

[0022] Appendix Figure 1 This is a schematic diagram of the structure of this utility model.

[0023] Appendix Figure 2 This is a schematic diagram of the preprocessing unit of this utility model.

[0024] Appendix Figure 3 This is a schematic diagram of the passage distribution structure of the direct condenser of this utility model.

[0025] Appendix Figure 4 This is a schematic diagram of the cooling water unit of this utility model.

[0026] Appendix Figure 5 This is a schematic diagram of the structure of the gas phase output pipe of this utility model.

[0027] Figure description: 1. Main output pipe; 2. Pretreatment unit; 3. Direct condenser; 4. Gas-liquid separator; 5. Measuring tank; 6. Cooling water unit; 7. Wastewater collection and treatment system. Pressure reducing valve 210, back pressure valve 220; Cooling water spray array 310, heat source fluid distributor 320; Liquid level detector 410, control valve 420; Weighing module 510; Condensing unit 610, cooling water storage tank 620; Dryer 810; First pressure measuring instrument 31, first temperature measuring instrument 32, first flow meter 33, second temperature measuring instrument 34, second flow meter 35, third temperature measuring instrument 37, third flow meter 81, second pressure measuring instrument 82, fourth temperature measuring instrument 83. Detailed Implementation

[0028] In the description of this utility model, it should be understood that the terms "upper", "lower", "inner", "outer", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship that the utility model product is usually placed in during use, or the orientation or positional relationship that is commonly understood by those skilled in the art. They are only used to facilitate the description of this utility model and to simplify the description, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0029] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, terms such as "set" and "connection" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0030] As one embodiment, a direct condensing geothermal fluid vapor-liquid ratio measurement system includes a main output pipe 1, a condensation unit, a separation unit, a cooling water unit 6, and a measurement unit. The main output pipe 1 is used to output the heat source fluid. The condensation unit includes a direct condensing condenser 3 for receiving the heat source fluid. The cooling water unit 6 is used to output cooling water into the direct condensing condenser 3. The separation unit includes a gas-liquid separator 4. The gas-liquid separator 4 includes a gas phase output pipe for outputting gas and a liquid phase output pipe for outputting liquid, and the liquid phase output pipe is connected to a measurement tank 5. The heat source fluid and cooling water are directly mixed and exchange heat in the direct condensing condenser 3. The resulting mixed fluid is output to the gas-liquid separator 4; the measuring unit includes a first pressure measuring instrument 31, a first temperature measuring instrument 32 and a first flow meter 33 installed at the input end of the direct condenser 3 that receives the heat source fluid, a second temperature measuring instrument 34 and a second flow meter 35 installed at the input end of the direct condenser 3 that receives cooling water, a third temperature measuring instrument 37 installed at the output end of the direct condenser 3 for discharging the mixed fluid, a weighing module 510 installed at the measuring tank 5, and a third flow meter 81, a second pressure measuring instrument 82 and a fourth temperature measuring instrument 83 installed at the gas phase output pipe.

[0031] The main output pipe 1 should be made of corrosion-resistant and temperature-resistant materials, such as titanium, 316L stainless steel, or 2205 duplex steel. Rock wool or aluminum silicate insulation can be installed on the outside of the output pipe to prevent heat loss and avoid burns. A first sampling pipe is installed at the gas phase output pipe. This first sampling pipe is used to directly sample the geothermal fluid. The material of the sampling pipe can be the same as that of the main output pipe 1, and it also needs to be covered with an insulation layer. A plug needs to be installed at the first sampling pipe at the end of sampling. A main valve 11 is also installed on the main output pipe 1 at the very front. The main valve 11 is used to completely cut off the heat source fluid, facilitating system installation, maintenance, and replacement. The main valve should be fully open during normal system operation.

[0032] The direct condenser 3 is preferably a vertical cylindrical container, made of corrosion-resistant and temperature-resistant materials such as titanium, 316L stainless steel, or 2205 duplex steel. Rock wool or aluminum silicate insulation can also be installed on the outside of the container. A transparent, pressure-resistant sight glass can be installed on the container for easy observation of the internal mixing. A safety valve interface can be installed at the top of the container to connect to an additional safety valve for monitoring and controlling the pressure inside the container. A thermometer interface and a level gauge interface can also be installed on the container to monitor the temperature and liquid level inside. In some preferred embodiments, the direct condenser 3 internally includes: a cooling water spray array 310 at the top, and a heat source fluid distributor 320 at the lower end of the cooling water spray array 310. The heat source fluid distributor 320 can be a ring pipe located in the upper middle part of the container. Multiple small holes or downward-spraying nozzles are opened below the ring pipe, allowing the heat source fluid to be sprayed downwards evenly, facilitating counter-current contact with the cooling water mist from above and enhancing mixing efficiency.

[0033] The cooling water unit 6 provides a constant, sufficient, and low-temperature cooling water supply to the direct-condensing condenser 3. It includes a condensing unit 610 and a cooling water storage tank 620 connected in sequence. The receiving end of the cooling water storage tank 620 receives the cooling water output from the condensing unit 610, and the output end of the cooling water storage tank 620 outputs cooling water to the direct-condensing condenser 3. The condensing unit 610 can be a constant-temperature water bath circulating unit (with compressor refrigeration), and the cooling water storage tank 620 can be an insulated water tank with a level gauge. A pump can be installed on the pipeline connecting the cooling water storage tank 620 and the direct-condensing condenser 3 to control the required water pressure and flow rate entering the direct-condensing condenser 3. The second temperature measuring instrument 34 can be a commonly used, high-precision thermometer such as a PT100 platinum resistance thermometer. The second flow meter 35 also needs to be a high-precision mass flow meter such as a Coriolis mass flow meter. The third temperature measuring instrument 37 can also be a PT100 platinum resistance thermometer, used to obtain the temperature of the condenser outlet. By monitoring this temperature, it is ensured that it does not exceed the saturation temperature, ensuring complete condensation of water vapor. Through the operation of the cooling water unit 6, the temperature of the cooling water input to the condenser 3 is kept within a stable low-temperature range (30-40℃), ensuring that water vapor can be almost completely condensed.

[0034] The weighing module 510 can use a high-precision weighbridge or load cell to continuously output weight signals. By calculating the increase in weight per unit time, the mass flow rate of the liquid can be obtained. The measuring tank 5 has an output port for connecting to a wastewater collection and treatment system 7, such as a commonly used neutralization tank or sedimentation tank.

[0035] The third flow meter 81 can be a wet gas flow meter or a thermal mass flow meter, the second pressure measuring instrument 82 can be a pressure transmitter or other common instruments, and the fourth temperature measuring instrument 83 can be a PT100 thermometer or other common instruments. More preferably, a second sampling tube is also provided on the main output pipe 1, located at the front end of the pretreatment unit 2. A plug can also be provided at the second sampling tube to seal it. The gas sampled through the second sampling tube can be easily measured offline, such as obtaining the mole fraction of each component of the gas using a gas chromatograph. As a further preferred embodiment, a dryer 810 is provided on the gas phase output pipe, located at the front end of the third flow meter 81, the second pressure measuring instrument 82, and the fourth temperature measuring instrument 83. The dryer 810 can be a container filled with silica gel or molecular sieve desiccant to ensure that the gas is completely dried and to prevent water vapor from being measured as condensed gas. Furthermore, since the mass of water vapor in the gas is extremely small compared to the total mass of the measuring tank 5, it has almost no impact on the data at the measuring tank 5.

[0036] It is understood that each instrument in the aforementioned measuring unit can be connected to a data acquisition and control system, such as a PLC (equipped with a display screen), and control programs can be written to achieve automatic adjustment and data recording (such as cooling water temperature and liquid level in the gas-liquid separator). These configurations are technologies known to those skilled in the art, and therefore will not be elaborated further.

[0037] As a further preferred embodiment, the main output pipe 1 is also equipped with a pretreatment unit 2 for regulating the pressure of the heat source fluid input to the direct condenser 3; the regulating pressure of the pretreatment unit 2 is greater than the flash pressure of the heat source fluid. The pretreatment unit 2 should be located at the rear end (downstream) of the first sampling pipe, including a pressure reducing valve 210 and a back pressure valve 220 connected in sequence. The pressure reducing valve 210 is mainly used to withstand the fluctuating high pressure (up to tens of bar) from the main output pipe 1, protecting the downstream back pressure valve 220 and precision testing instruments from the impact of drastic pressure fluctuations upstream. The back pressure valve 220 is mainly used to control the outlet pressure (i.e., the regulating pressure) to ensure that it is stable at the set value. The first pressure measuring instrument 31, the first temperature measuring instrument 32, and the first flow meter 33 are all located at the rear end of the back pressure valve. The first pressure measuring instrument 31 can be a commonly used device such as a piezoresistive pressure transmitter, the first temperature measuring instrument 32 can be a commonly used high-precision thermometer such as a PT100 platinum resistance thermometer, and the first flow meter 33 can be a commonly used instrument such as a wedge flow meter.

[0038] As a further preferred embodiment, a liquid level detector 410 is installed inside the gas-liquid separator 4, and a control valve 420 is installed on the liquid phase output pipe. The gas-liquid separator 4 is a commonly used device by those skilled in the art and can be directly purchased, so it will not be described in detail. The liquid level detector 410 can be a commonly used instrument such as a radar level gauge, mainly used to monitor the liquid level in order to control the opening and closing state of the control valve 420, thereby maintaining the liquid level in a stable state.

[0039] The above-mentioned direct condensing geothermal fluid vapor-liquid ratio measurement system can be used in conjunction with the measurement method, specifically including the following steps: S1. Direct Data Acquisition: The pressure P1 of the heat source fluid is acquired through the first pressure measuring instrument 31; the temperature T1 of the heat source fluid is acquired through the first temperature measuring instrument 32; and the mass flow rate M1 of the heat source fluid is acquired through the first flow meter 33. The temperature T2 of the cooling water is acquired through the second temperature measuring instrument 34; and the mass flow rate M2 of the cooling water is acquired through the second flow meter 35. The temperature T3 of the mixed fluid is acquired through the third temperature measuring instrument 37. The mass M3 of the mixed fluid is acquired through the weighing module 510. The volumetric flow rate V4 of the gas is acquired through the third flow meter 81; the pressure P4 of the gas is acquired through the second pressure measuring instrument 82; and the temperature T4 of the gas is acquired through the fourth temperature measuring instrument 83. S2. Obtain the gas at the gas phase output pipe and perform composition analysis, and calculate the gas mass M4 and specific enthalpy h4; S3. Calculate the mass MS of water vapor in the heat source gas: MS=[M1*h1-(M3-M2)* hL-M4*h4] / (hS-hL); Where MS refers to the mass of water vapor, in kg; M1 refers to the mass of the heat source fluid, in kg; M2 refers to the mass of the cooling water, in kg; M3 refers to the mass of the mixed fluid, in kg; and M4 refers to the mass of the non-condensable gas, in kg. h1 refers to the specific enthalpy of the heat source gas under the pressure conditions before the direct condenser, in kJ / kg; hS refers to the specific enthalpy of water vapor in the heat source gas under the pressure conditions before the direct condenser, in kJ / kg; hL refers to the specific enthalpy of liquid water in the heat source gas under the pressure conditions before the direct condenser, in kJ / kg; h4 is the specific enthalpy of the non-condensable gas, in kJ / kg. S4. Calculate the mass of liquid water (ML): ML = M3 - M2 - MS; where ML refers to the mass of liquid water in the heat source fluid, in kg. S5. Calculate the mass percentage: Liquid water ratio = ML / M1 * 100%; Water vapor ratio = MS / M1 * 100%; Non-condensable gas ratio = M4 / M1 * 100%.

[0040] Where (hS-hL) corresponds to the latent heat of vaporization, which can be directly looked up in the latent heat of vaporization table. hL can also be found in a table (such as the NIST standard database). h4 is the specific enthalpy of the noncondensable gas, which can be calculated. One method for calculating h4 has been discussed above, and the method for calculating the enthalpy of a gas mixture disclosed in application number 2023106953132 can also be used. Therefore, the values ​​of MS and ML can be obtained through simple calculations. Due to the complex composition of noncondensable gases, the calculation of M4 is relatively complex. A commonly used calculation formula in this field can be used, as follows: M4=(P4*V4*M_avg) / (R*T4); V4, P4, and T4 are already known from the above; M_avg is the average molar mass, in kJ / mol, which can be determined by calculating the gas composition when calculating h4, and can be obtained by calculating the average molar mass of the mixed gas; R is the gas constant, a constant value, in J / (mol·K). The specific embodiments described herein are merely illustrative examples of the spirit of this utility model. Those skilled in the art to which this utility model pertains can make various modifications or additions to the described specific embodiments or use similar methods to replace them, but without departing from the spirit of this utility model or exceeding the scope defined by the appended claims.

Claims

1. A direct condensing geothermal fluid vapor-liquid ratio measurement system, comprising a main output pipe (1), a condensation unit, a separation unit, a cooling water unit (6), and a measurement unit; characterized in that: The main output pipe (1) is used to output the heat source fluid; the condensation unit includes a direct condenser (3) for receiving the heat source fluid; the cooling water unit (6) is used to output cooling water into the direct condenser (3); the separation unit includes a gas-liquid separator (4); the gas-liquid separator (4) includes a gas phase output pipe for outputting gas and a liquid phase output pipe for outputting liquid, the liquid phase output pipe being connected to the measuring tank (5); the heat source fluid and the cooling water are directly mixed and exchanged heat in the direct condenser (3), and the resulting mixed fluid is output into the gas-liquid separator (4); The measuring unit includes a first pressure measuring instrument (31), a first temperature measuring instrument (32), and a first flow meter (33) installed at the input end of the direct condensing condenser (3) for receiving heat source fluid; a second temperature measuring instrument (34) and a second flow meter (35) installed at the input end of the direct condensing condenser (3) for receiving cooling water; a third temperature measuring instrument (37) installed at the output end of the direct condensing condenser (3) for discharging the mixed fluid; a weighing module (510) installed at the measuring tank (5); and a third flow meter (81), a second pressure measuring instrument (82), and a fourth temperature measuring instrument (83) installed at the gas phase output pipe.

2. The direct condensation geothermal fluid vapor-liquid ratio measurement system according to claim 1, characterized in that: The main output pipe (1) is also provided with a pretreatment unit (2) for adjusting the pressure of the heat source fluid input into the direct condenser (3).

3. The direct condensation geothermal fluid vapor-liquid ratio measurement system according to claim 2, characterized in that: The pretreatment unit (2) includes a pressure reducing valve (210) and a back pressure valve (220) connected in sequence.

4. The direct condensing geothermal fluid vapor-liquid ratio measurement system according to claim 1, characterized in that: The direct condenser (3) is internally provided with: a cooling water spray array (310) located at the top, and a heat source fluid distributor (320) located at the lower end of the cooling water spray array (310).

5. The direct condensation geothermal fluid vapor-liquid ratio measurement system according to claim 1, characterized in that: The cooling water unit (6) includes a condenser unit (610) and a cooling water storage tank (620) connected in sequence; the receiving end of the cooling water storage tank (620) is used to receive the cooling water output by the condenser unit (610), and the output end of the cooling water storage tank (620) outputs cooling water to the direct condenser (3).

6. The direct condensing geothermal fluid vapor-liquid ratio measurement system according to claim 1, characterized in that: The gas-liquid separator (4) is equipped with a liquid level detector (410), and a control valve (420) is installed on the liquid phase output pipe.

7. The direct condensing geothermal fluid vapor-liquid ratio measurement system according to claim 1, characterized in that: A dryer (810) is provided on the gas phase output pipe, and the dryer (810) is located in front of the third flow meter (81), the second pressure measuring instrument (82) and the fourth temperature measuring instrument (83).

8. The direct condensing geothermal fluid vapor-liquid ratio measurement system according to claim 1, characterized in that: A first sampling tube is installed at the gas phase output pipe.

9. A direct condensing geothermal fluid vapor-liquid ratio measurement system according to claim 2, characterized in that: The main output tube (1) is also provided with a second sampling tube located at the front end of the preprocessing unit (2).

10. A direct condensing geothermal fluid vapor-liquid ratio measurement system according to claim 2, characterized in that: The main output pipe (1) is also equipped with a main valve (11) located at the front end of the pretreatment unit (2).

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