CN112031751B - Bypass type gas-liquid separation type geothermal energy productivity test system - Google Patents

Abstract

The invention discloses a bypass type gas-liquid separation type geothermal energy production testing system, which includes a production well, a wellhead valve, a gas-liquid separator, a condenser, a cooling tower, a cooling pump, a booster pump and a recharge well; The inlet is connected to the heat source outlet of the production well, and the end is provided with a tee; one outlet of the tee is connected to the inlet of the gas-liquid separator, and the other outlet is connected to the recharge well; the liquid outlet of the gas-liquid separator is connected to the inlet of the booster pump Connected; the gas outlet of the gas-liquid separator is connected with the inlet of the condenser; the gas outlet of the condenser is connected with the atmosphere; the condensed water outlet of the condenser is connected with the inlet of the cooling tower; the outlet of the cooling tower is connected with the inlet of the cooling pump; the cooling The outlet of the pump is connected with the condensed water inlet of the condenser; the liquid outlet of the condenser is connected with the inlet of the booster pump; the outlet of the booster pump is connected with the recharge well. The system is equipped with a wellhead valve to adjust the outlet flow to obtain the geothermal fluid flow and composition at the wellhead and the geothermal production value.

Description

A bypass type gas-liquid separation geothermal energy production testing system

technical field

The invention belongs to the technical field of geothermal energy production testing, in particular to a bypass type gas-liquid separation geothermal energy production testing system.

Background technique

In recent years, geothermal resources have gradually entered our field of vision with a series of advantages such as abundant reserves, low environmental pollution, and renewable. Geothermal resources are mainly divided into hydrothermal resources and hot dry rocks. At present, the development of geothermal resources mainly focuses on hot dry rocks. Hot dry rock is a high-temperature rock mass buried 3-10 km underground, with a temperature generally greater than 200 °C, and has economic development value. Hot dry rock resources have the characteristics of wide distribution, low pollution emissions, renewable, good thermal energy continuity, and are not restricted by seasons and climatic conditions. Studies have shown that the energy in shallower hot dry rock resources includes oil and natural gas. More than 300 times the energy of all fossil fuels including coal. Putting hot dry rock geothermal resources into operation for power generation is of great significance to energy conservation and emission reduction, and has certain commercial feasibility.

The geothermal productivity of hot dry rock is an important index to evaluate the quality of geothermal reservoirs, and the efficient heat exchange cycle between wells is the prerequisite for geothermal productivity testing. The geothermal fluid produced by the wellhead of the high-grade medium-high temperature geothermal recovery well is usually a multi-component gas-liquid two-phase containing a part of non-condensable gas. Since the thermophysical parameters and thermodynamic properties of non-condensable gas, water vapor, and geothermal water are quite different, if the composition of the geothermal fluid produced by the hot dry rock wellhead cannot be determined, it will be very difficult to use it as a heat source for power generation at this time. uncertainty.

Contents of the invention

Aiming at the deficiencies of the prior art, the technical problem to be solved by the present invention is to provide a bypass type gas-liquid separation type geothermal energy production testing system.

The technical solution of the present invention to solve the technical problem is to provide a bypass type gas-liquid separation type geothermal energy production test system, which is characterized in that the test system includes production wells, wellhead valves, gas-liquid separators, condensers, cooling towers , cooling pumps, booster pumps and recharge wells;

The heat source outlet of the production well is connected with the inlet of the wellhead valve; the outlet pipeline of the wellhead valve is equipped with a temperature sensor, a pressure sensor and a flow meter, and a tee is installed at the end; one outlet of the tee is connected with the inlet of the gas-liquid separator through the pipeline , a flowmeter is set on the pipeline; the other outlet of the tee is connected to the reinjection well; the liquid outlet of the gas-liquid separator is connected to the inlet of the booster pump through the pipeline, and a temperature sensor, a pressure sensor and a flowmeter are set on the pipeline ;The gas outlet of the gas-liquid separator communicates with the inlet of the condenser through a pipeline, and a temperature sensor, a pressure sensor and a flow meter are arranged on the pipeline; the gas outlet of the condenser communicates with the outside atmosphere through a pipeline, and a temperature sensor is arranged on the pipeline , pressure sensor and flowmeter; the condensate outlet of the condenser is connected with the inlet of the cooling tower through a pipeline, and a temperature sensor is installed on the pipeline; the outlet of the cooling tower is connected with the inlet of the cooling pump through a pipeline, and a flowmeter is installed on the pipeline The outlet of the cooling pump communicates with the condensed water inlet of the condenser through a pipeline, and a temperature sensor is arranged on the pipeline; the liquid outlet of the condenser communicates with the inlet of the booster pump through a pipeline, and a temperature sensor, a pressure sensor and a pressure sensor are arranged on the pipeline. flow meter; the outlet of the booster pump communicates with the reinjection well.

Compared with the prior art, the present invention has the beneficial effects of:

(1) The test system is equipped with a wellhead valve. By controlling the opening of the wellhead valve and reasonably adjusting the flow rate at the wellhead outlet, the mass flow rate of the geothermal fluid at the wellhead of the geothermal well, the composition of the geothermal fluid, and the ratio of vapor to liquid can be obtained, so as to obtain the flow rate at the wellhead. Geothermal production values such as total enthalpy and energy flow curves of geothermal fluids provide reliable basic data for the design of hot dry rock geothermal power generation systems.

(2) The test system is equipped with a gas-liquid separator, which can cause the heat-carrying fluid to flash in the gas-liquid separator to realize gas-liquid separation.

(3) The test system is equipped with a condenser, which is used to condense and separate the gas after gas-liquid separation from the non-condensable gas, so as to obtain the content of the non-condensable gas.

(4) The test system is equipped with temperature sensors, pressure sensors and flow meters at wellhead valves, gas-liquid separator outlets, and condenser outlets, which can more accurately monitor the temperature, pressure and flow of geothermal fluids.

(5) The test system is equipped with a booster pump, which can pressurize the low-pressure fluid flowing out of the liquid outlet of the condenser and the low-pressure fluid separated from the liquid outlet of the gas-liquid separator.

Description of drawings

Fig. 1 is a schematic diagram of a bypass type gas-liquid separation geothermal energy production testing system of the present invention.

In the figure: 1-production well; 2-wellhead valve; 3-gas-liquid separator; 4-condenser; 5-cooling tower; 6-cooling pump; 7-boosting pump; 8-reinjection well.

Detailed ways

Specific examples of the present invention are given below. The specific embodiments are only used to further describe the present invention in detail, and do not limit the protection scope of the claims of the present application.

The present invention provides a bypass type gas-liquid separation type geothermal productivity testing system (referred to as the testing system, see Figure 1), which is characterized in that the testing system includes a production well 1, a wellhead valve 2, a gas-liquid separator 3, and a condenser 4. Cooling tower 5, cooling pump 6, booster pump 7 and recharge well 8;

The heat source outlet of the production well 1 is communicated with the inlet of the wellhead valve 2; the outlet pipeline of the wellhead valve 2 is provided with a temperature sensor, a pressure sensor and a flow meter, and a tee is provided at the end; an outlet of the tee is connected with the gas-liquid separator 3 The inlet of the pipe is connected through a pipeline, and a flow meter is arranged on the pipeline; the other outlet of the tee is connected with the recharge well 8; the liquid outlet at the bottom of the gas-liquid separator 3 is connected with the inlet of the booster pump 7 through a pipeline, and A temperature sensor, a pressure sensor and a flowmeter are provided; the gas outlet at the top of the gas-liquid separator 3 communicates with the inlet of the condenser 4 through a pipeline, and a temperature sensor, a pressure sensor and a flowmeter are arranged on the pipeline; the gas outlet of the condenser 4 It communicates with the outside atmosphere through a pipeline, and a temperature sensor, a pressure sensor and a flow meter are arranged on the pipeline; the condensed water outlet of the condenser 4 is communicated with the inlet of the cooling tower 5 through a pipeline, and a temperature sensor is arranged on the pipeline; The outlet communicates with the inlet of the cooling pump 6 through a pipeline, and a flow meter is arranged on the pipeline; the outlet of the cooling pump 6 communicates with the condensed water inlet of the condenser 4 through a pipeline, and a temperature sensor is arranged on the pipeline; the liquid outlet of the condenser 4 The pipeline is connected with the inlet of the booster pump 7 , and the pipeline is provided with a temperature sensor, a pressure sensor and a flow meter; the outlet of the booster pump 7 is connected with the recharge well 8 .

The function of the wellhead valve 2 is to adjust the opening of the valve to control the flow rate of the produced heat-carrying fluid.

The function of the gas-liquid separator 3 is to cause the heat-carrying fluid to flash and separate gas and liquid through decompression and capacity expansion.

Preferably, a temperature sensor, a pressure sensor and a flow meter are sequentially arranged on the outlet pipeline of the wellhead valve 2 .

Preferably, a temperature sensor, a pressure sensor and a flow meter are sequentially arranged on the pipeline between the liquid outlet of the gas-liquid separator 3 and the inlet of the booster pump 7 .

Preferably, a temperature sensor, a pressure sensor and a flow meter are sequentially arranged on the pipeline between the gas outlet of the gas-liquid separator 3 and the inlet of the condenser 4 .

Preferably, a temperature sensor, a pressure sensor and a flow meter are sequentially arranged on the pipeline between the gas outlet of the condenser 4 and the outside atmosphere.

Preferably, a temperature sensor, a pressure sensor and a flow meter are sequentially arranged on the pipeline between the liquid outlet of the condenser 4 and the inlet of the booster pump 7 .

The working principle and working process of the present invention are: after the fluid exchanges heat with the underground hot dry rock, it becomes a high-temperature and high-pressure dry hot rock heat-carrying fluid, which is output from the production well 1 and flows to the tee after passing through the wellhead valve 2; Before the tee, the temperature, pressure and flow rate of the heat-carrying fluid flowing through the wellhead valve 2 are respectively measured by the temperature sensor, pressure sensor and flow meter; part of the heat-carrying fluid flowing through the tee enters the gas-liquid separator 3, and passes The flow meter in front of the liquid separator 3 is used to monitor the flow rate of the heat-carrying fluid entering the gas-liquid separator 3; the heat-carrying fluid is flashed through the gas-liquid separator 3 to realize gas-liquid separation; the separated steam and non-condensable The gas flows out through the gas outlet of the gas-liquid separator 3, and flows into the condenser 4 after measuring the temperature, pressure and flow rate of the separated steam and non-condensable gas through a temperature sensor, a pressure sensor and a flow meter respectively; The steam and non-condensable gas are condensed through the condenser 4, and the non-condensable gas is discharged from the gas outlet of the condenser 4, and the temperature, pressure and flow rate of the non-condensable gas are respectively detected by a temperature sensor, a pressure sensor and a flow meter before being discharged; separation The outgoing steam is condensed into liquid condensed water in the condenser 4, and the condensed water flows out from the condensed water outlet of the condenser 4 and flows into the cooling tower 5 for cooling; a temperature sensor is installed in front of the cooling tower 5 to measure the condensed water temperature; the cooled condensed water flows out from the cooling tower 5 and enters the cooling pump 6 for pressurization; a flow meter is arranged in front of the cooling pump 6 to measure the flow rate of the cooled condensed water; the pressurized condensed water is The pump is pumped into the condenser 4, and a temperature sensor is installed in front of the condenser 4 to measure the temperature of the condensed water after pressurization; the steam flowing out of the gas outlet of the gas-liquid separator 3 becomes a low-temperature and low-pressure fluid after condensation and heat exchange It is discharged from the liquid outlet of the condenser 4, and after the temperature sensor, pressure sensor and flow meter respectively measure the temperature, pressure and flow rate of the fluid after condensation and heat exchange, the liquid outlet of the separator 3 passes through the temperature sensor, pressure sensor and flow rate The temperature, pressure and flow measured by the meter are mixed and then pressurized by the booster pump 7, and then injected into the reinjection well 8 together with another part of the heat-carrying fluid from the tee branch. The heat transfer fluid produced from the production well 1 is finally reinjected into the reinjection well 8 .

Example

Taking the Yangyidi thermal power station in Tibet as an example, the heat-carrying fluid of dry hot rock produced at the wellhead of production well 1 is tested by adjusting the opening of the wellhead valve 2 and reducing the total flow rate by 10% each time. Adjust the time interval according to the on-site test situation, and reduce it in turn until it reaches 30% of the total flow, and complete the variable working condition test.

Through the test results of different flow rates, it is finally calculated that the temperature of the hot dry rock heat-carrying fluid produced at the wellhead of production well 1 is 168°C, and the pressure is 0.76PMa. The geothermal water, geothermal water steam and The flow rates of non-condensable gases are 581.3m ³ /s, ^{42.74m 3} /s and 0.96m ³ /s respectively, and then the proportions of geothermal water, geothermal steam and non-condensable gases are respectively 93%, 6.846% and 0.154%.

What is not mentioned in the present invention is applicable to the prior art.

Claims (6)

1. A bypass type gas-liquid separation type geothermal energy production test system, characterized in that the test system includes production wells, wellhead valves, gas-liquid separators, condensers, cooling towers, cooling pumps, booster pumps and recharge wells ; The heat source outlet of the production well is connected with the inlet of the wellhead valve; the outlet pipeline of the wellhead valve is equipped with a temperature sensor, a pressure sensor and a flow meter, and a tee is installed at the end; one outlet of the tee is connected with the inlet of the gas-liquid separator through the pipeline , a flowmeter is set on the pipeline; the other outlet of the tee is connected to the reinjection well; the liquid outlet of the gas-liquid separator is connected to the inlet of the booster pump through the pipeline, and a temperature sensor, a pressure sensor and a flowmeter are set on the pipeline ;The gas outlet of the gas-liquid separator communicates with the inlet of the condenser through a pipeline, and a temperature sensor, a pressure sensor and a flow meter are arranged on the pipeline; the gas outlet of the condenser communicates with the outside atmosphere through a pipeline, and a temperature sensor is arranged on the pipeline , pressure sensor and flowmeter; the condensate outlet of the condenser is connected with the inlet of the cooling tower through a pipeline, and a temperature sensor is installed on the pipeline; the outlet of the cooling tower is connected with the inlet of the cooling pump through a pipeline, and a flowmeter is installed on the pipeline The outlet of the cooling pump communicates with the condensed water inlet of the condenser through a pipeline, and a temperature sensor is arranged on the pipeline; the liquid outlet of the condenser communicates with the inlet of the booster pump through a pipeline, and a temperature sensor, a pressure sensor and a pressure sensor are arranged on the pipeline. flow meter; the outlet of the booster pump communicates with the reinjection well. 2. The bypass-type gas-liquid separation geothermal productivity testing system according to claim 1, characterized in that a temperature sensor, a pressure sensor and a flow meter are sequentially arranged on the outlet pipeline of the wellhead valve. 3. The bypass-type gas-liquid separation geothermal production capacity testing system according to claim 1, characterized in that a temperature sensor and a pressure sensor are sequentially arranged on the pipeline between the liquid outlet of the gas-liquid separator and the inlet of the booster pump and flow meter. 4. The bypass type gas-liquid separation type geothermal energy production testing system according to claim 1, characterized in that the pipeline between the gas outlet of the gas-liquid separator and the inlet of the condenser is sequentially provided with a temperature sensor, a pressure sensor and a flow meter. 5. The bypass-type gas-liquid separation geothermal energy production testing system according to claim 1, characterized in that a temperature sensor, a pressure sensor and a flow meter are sequentially arranged on the pipeline between the gas outlet of the condenser and the outside atmosphere. 6. The bypass-type gas-liquid separation geothermal production capacity testing system according to claim 1, characterized in that the pipeline between the liquid outlet of the condenser and the inlet of the booster pump is sequentially provided with a temperature sensor, a pressure sensor and a flow rate count.

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