110 results about "Geothermal fluid" patented technology

The invention discloses a deep geothermal fluid cause and migration path tracing method, and relates to the technical field of earth scientific exploration, and the method specifically comprises the following steps: A1, collecting a geothermal fluid sample, A2, fusing high-precision three-dimensional seismic data, logging data and drilling data, constructing a multi-scale fracture network model, quantifying fracture connectivity and permeability anisotropy, and calculating the fracture connectivity and permeability anisotropy according to the fracture connectivity and permeability anisotropy. A3, developing a long short-term memory (LSTM) network model, inputting temperature, pressure and chemical field data monitored in real time, dynamically predicting a fluid migration path, and introducing a generative adversarial network (GAN) optimization model, and A4, deploying a distributed optical fiber sensor network. According to the sensing method for the aviation high-speed moving target, through the core-shell structure tracer agent, high fluorescence efficiency and geological compatibility are considered, a complete innovation chain is formed in the aspects of material design, detection method and environmental adaptability of the nano tracer agent, and the precision and sustainability of tracing of a migration path of deep geothermal fluid are remarkably improved.

Methods are provided for extracting thermal energy from a geothermal reservoir having at least one feature extending therethrough, which involve drilling or accessing a production well that intersects the at least one feature, wherein the at least one feature provides a flow path of pressurized geothermal fluid into the production well. Well log data can be analyzed to determine position of the at least one feature in the production well. One or more interventions, or combinations of interventions, can be performed to open the feature or otherwise enhance the flow rate of pressurized geothermal fluid carried by the feature into the production well. The intervention(s) can be performed on multiple features that connect to the production well. The method can also be applied to multiple production wells.

The present disclosure provides a non-condensable gas reduction system that reduces the effects of atmospheric components contained in gas that is reduced in the reduction well. [Solution] A non-condensable gas reduction system in a geothermal power plant returns non-condensable gas that remains uncondensed when cooled from a first gas contained in geothermal fluid that springs from a production well to a reinjection well. The non-condensable gas reduction system comprises: a pump that pressurizes the first liquid sent to the reinjection well; an ejector that is driven by the first liquid, attracts the non-condensable gas, and discharges a second liquid that is a mixture of the first liquid and the non-condensable gas; and a gas separator connected downstream of the ejector that separates the second gas containing atmospheric components that has been mixed into the second liquid, and discharges the second gas into the atmosphere while discharging the second liquid into the reinjection well.

The invention provides a green compound scale inhibitor for geothermal fluid. The compound scale inhibitor comprises modified polyaspartic acid, high-hydrolysis polymaleic anhydride, polyepoxysuccinic acid and polyacrylic acid. According to the environment-friendly compound scale inhibitor for the geothermal fluid, the modified polyaspartic acid, the high-hydrolysis polymaleic anhydride, the polyepoxysuccinic acid and the polyacrylic acid are compounded, a good synergistic effect is achieved, scale inhibition is achieved through chelation solubilization and lattice distortion, the scale inhibition advantage in actual geothermal water is obvious, and the environment-friendly compound scale inhibitor has a good actual popularization value.

The invention discloses a cationic polymer scale inhibitor as well as a preparation method and application thereof, and relates to the field of scale inhibitors in geothermal pipelines, the scale inhibitor limits easy-to-scale metal from adhering and scaling on a coating through cationic groups on polymer molecule side chains, meanwhile, the surface contact angle of the coating is increased through functional components with low surface energy, and the scale inhibitor can be used for inhibiting scale formation of the coating. The cationic polymer-based scale inhibitor has the advantages that the cationic polymer-based scale inhibitor is added into the geothermal fluid, so that some granular solid components of the geothermal fluid are difficult to accumulate on the coating to form a crystallized nucleation center, the problems of scaling and accumulation are fundamentally solved, in addition, the cationic polymer-based scale inhibitor has excellent adhesive force with the geothermal pipeline, and guarantee is provided for the corrosion resistance and the long-term effect of the coating.

Various examples are provided related to airlift pumping of downhole geothermal fluids. In one example, an airlift system includes a compressor; a gas sparger head in a wellbore of a geothermal well, and a pressure head recycle assembly. The sparger head produces artificial lift of the geothermal fluids by injecting a gas resulting in a difference in density downhole. The entrained gas can be extracted by the pressure head recycle assembly, compressed, and reinjected downhole. The geothermal fluid at the well head can be used in direct use applications or in a thermodynamic cycle to make shaft power. The gas sparger head can include a venturi shaped passage extending through the gas sparger head and a bubble orifice including gas orifices radially spaced about a narrow portion of the venturi shaped passage. The gas orifices can have a corresponding resonant chamber through which the gas (e.g., air) is provided.

The invention relates to the field of energy engineering, in particular to a comprehensive energy utilization system combining a pumped storage power station and a hydrothermal type geothermal resource development system, comprising: a pumped storage power station for storing energy during the off-peak period of power grid load and generating power during the peak period; the hydrothermal type geothermal resource development system is used for collecting and utilizing geothermal energy and comprises a water injection well forming fluid circulation, a hot water reservoir, a water pumping well and a geothermal utilization system. The pressure coupling device is used for connecting a water drainage pipeline of the pumped storage power station with a water injection well of the hydrothermal geothermal resource development system and driving geothermal fluid to circulate by utilizing pressure generated during water drainage; and the energy conversion and control system is used for monitoring the load of the power grid, the operation condition of the geothermal well and the energy storage state of the pumped storage power station in real time, and regulating and controlling the working mode of the pumped storage power station and the collection and utilization of geothermal energy according to the monitored operation data.

A method for removing scale that is precipitated from geothermal fluid containing dissolved silica and becomes adherent in a geothermal power plant including: a water supply pump for pumping the geothermal fluid from a production well; a gas-water separator for separating the geothermal fluid into geothermal water and geothermal steam; and a turbine for rotating by being supplied with the geothermal steam separated by the gas-water separator includes: forming a surface of a location in the geothermal power plant contacted by the geothermal fluid from diamond-like carbon in a first region extending from the production well to the turbine; forming at least the surface of the location in the geothermal power plant from at least one selected from diamond-like carbon, polytetrafluoroethylene, and polyvinyl chloride in a region other than the first region; and injecting a scale removing liquid into a flow path including the surface of the location.

The invention belongs to the technical field of efficient mining of closed mine terrestrial heat, and particularly relates to an efficient mining device and method for closed mine terrestrial heat, the efficient mining device comprises an inner pipe, an outer pipe is arranged outside the inner pipe, the outer wall of the outer pipe is fixedly connected with a high-temperature-resistant lining layer, and the outer wall of the high-temperature-resistant lining layer is fixedly connected with an efficient heat preservation layer; the outer wall of the efficient heat preservation layer is fixedly connected with a protective outer layer. The inner pipe adopts a spiral shape and covers the fins, the outer pipe constructs a multi-layer protection system, and the inner pipe and the outer pipe cooperate to lay a foundation for efficient heat exchange and energy transmission. The inner pipe is made of aluminum bronze, heat of geothermal fluid can be rapidly absorbed by means of the high heat conductivity coefficient of 35-50 W / (m.K) of the inner pipe, the fluid flowing path is ingeniously prolonged by means of the spiral structure design, the fluid turbulence degree is enhanced in cooperation with fins, the heat exchange area is remarkably increased, and the heat exchange efficiency is improved by 30% or above compared with a traditional straight pipe structure.

The present disclosure provides a non-condensable gas reduction system that returns non-condensable gas contained in highly maintainable geothermal fluid to a reinjection well. 【Solution means】A gas-liquid separator that separates geothermal fluid gushing out from a production well into a first gas and a first liquid, an evaporator that exchanges heat between the first gas and a working medium, a turbine that is rotated by the working medium discharged from the evaporator, and a condenser that cools the working medium that has rotated the turbine and condenses the working medium into a liquid. A non-condensable gas reduction system used in a geothermal power plant, comprising a pump that pressurizes a third liquid sent to a reinjection well, a plurality of ejectors that are driven by the third liquid, attract non-condensable gas contained in the first gas and remaining uncondensed in the evaporator, and discharge a fourth liquid in which the third liquid and the non-condensable gas are mixed, and a plurality of ejectors including any one of the plurality of ejectors. A non-condensable gas reduction system provided in parallel, in which the first liquid and the fourth liquid are mixed and sent to a reinjection well.

The present disclosure provides a non-condensable gas reduction system that returns non-condensable gas contained in highly maintainable geothermal fluid to a reinjection well. **Solution**: A non-condensable gas reduction system used in a geothermal power plant, comprising: a gas-liquid separator that separates geothermal fluid gushing out from a production well into a first gas and a first liquid; a turbine rotated by the first gas; and a condenser that cools the first gas rotated by the turbine and condenses vapor contained in the first gas into a second liquid, the non-condensable gas reduction system further comprising: a pump that pressurizes a third liquid sent to a reinjection well; a plurality of ejectors driven by the third liquid, attracting non-condensable gas contained in the first gas and remaining uncondensed in the condenser, and discharging a fourth liquid in which the third liquid and the non-condensable gas are mixed; and a plurality of lines provided in parallel, including any one of the plurality of ejectors, wherein the first liquid and the fourth liquid are mixed and sent to the reinjection well.

The invention discloses a geothermal fluid source discrimination method based on geochemical index and machine learning fusion, and relates to the technical field of geothermal resource intelligent exploration, and the method comprises the steps: firstly collecting and calculating multi-dimensional geochemical indexes, and constructing a standardized feature sequence; establishing an end member feature library by using unsupervised clustering; identifying the source type of the fluid through a discrimination model fused with an attention mechanism; aiming at the mixed source fluid, constructing an optimization model embedded with physical and chemical constraints, and quantitatively inverting the contribution proportion of each end member; and finally, on the basis of the time sequence proportion data obtained by inversion, predicting a future evolution trend by adopting a time convolutional network-long and short-term memory network model fused with an attention mechanism. According to the geothermal fluid source discrimination method based on geochemical index and machine learning fusion provided by the invention, the whole-process intelligent analysis of the geothermal fluid source from qualitative identification to quantitative prediction is realized.

The application discloses a hydrogen production system of geothermal water source and belongs to the technical field of hydrogen production. The system comprises a geothermal fluid circulation unit, an electrolyte preheating unit and an electrolytic hydrogen production unit. The geothermal fluid circulation unit realizes the recycling of geothermal water through a geothermal well, a recharge well and a geothermal heat exchanger; the electrolyte preheating unit connects an electrolyte storage tank and the second side of the geothermal heat exchanger through a second circulation pipeline to form a preheating circulation; the electrolytic hydrogen production unit comprises an electrolytic tank and a hydrogen purification device and receives the preheated electrolyte to produce hydrogen by electrolysis. In the preferred scheme, a flash evaporation pressurization and heat supplement unit is further included, the geothermal tail water is subjected to waste heat recovery through a flash tank and a steam compressor to generate high-temperature steam for auxiliary heating of the electrolytic tank. The application uses geothermal energy to replace electric heating to preheat electrolyte, significantly reduces the energy consumption of hydrogen production, has the advantages of reasonable structure, high automation degree, environmental protection and water saving and is suitable for hydrogen production application in areas rich in geothermal resources.

The present application relates to the field of geothermal energy supply technology, and provides a geothermal energy supply system for developing and utilizing geothermal reservoirs using an open U-shaped well, including a geothermal component and an energy supply mechanism. The geothermal component has a connected screen and a heat exchanger to form a geothermal loop. The screen is set in the formation and filled with gravel on both sides of the screen. The screen has screen holes connecting the inside and outside. Heat conduction is formed between the screen, gravel and the formation. The geothermal fluid circulates in the geothermal loop and is heated by the screen, gravel and formation. The first energy supply unit in the energy supply mechanism is connected to the geothermal loop, and converts the kinetic energy and thermal energy of the geothermal fluid into electrical energy output. The second energy supply unit and the heat exchanger are correspondingly arranged, and convert the thermal energy of the geothermal fluid into electrical energy output. The third energy supply unit and the heat exchanger are correspondingly arranged, and the thermal energy of the geothermal fluid is transferred to the preset liquid in the third energy supply unit and output as thermal energy. Through such an arrangement, the charging efficiency and utilization rate of the geothermal fluid are improved.

The present invention discloses an integrated system for geothermal energy-driven CO2 hybrid heating power generation and storage, including a geothermal water circulation pump, which is used to extract and transfer the hot water from the production well to the contact mixing heater. A liquid distribution pipe is arranged in the contact mixing heater, and the outlet end of the liquid distribution pipe is located inside the mixing heater. The liquid outlet end of the mixing heater is used to connect to the reinjection well; the liquid distribution pipe is used to receive CO 2； The swirl chamber is connected to the top of the contact mixing heater. The liquid outlet of the swirl chamber is connected to the bottom of the contact mixing heater. The top gas outlet of the swirl chamber is connected to the inlet of the expander. The outlet of the expander is connected to the inlet of the condenser. The outlet of the condenser is connected to the liquid distribution pipe. The circulating working medium CO2 directly exchanges heat with the geothermal fluid through the liquid distribution pipe and the liquid outlet. Compared with the traditional indirect contact heat exchange, the heat transfer efficiency is greatly improved, the heat transfer area is greatly reduced, and the investment cost is reduced.

The present invention discloses a heat exchange sleeve device and method for efficiently exploiting geothermal resources, and relates to the technical field of energy recovery equipment. The present invention includes a geothermal layer, wherein a geothermal pipe is installed inside the geothermal layer, and a heat-absorbing metal sheet is installed on the bottom surface of the geothermal pipe; a circulation component is provided on the top of the geothermal layer, and the circulation component includes a main water tank. The present invention can circulate and recover the heat energy in the geothermal layer through the setting of the circulation component. When the working medium circulating fluid enters the geothermal pipe, it forms convection around the geothermal fluid, realizes heat transfer, and effectively improves the utilization efficiency of thermal energy. Through the setting of the diversion component, the opening and closing of the first circulation pipe and the second circulation pipe can be controlled. By changing the circulation direction of the second circulation pipe, the working medium circulating fluid can be concentratedly introduced into the auxiliary water tank, which is convenient for use in an external low-temperature environment, further improving the utilization efficiency of thermal energy.

System, method, and apparatus for harnessing geothermal power from superhot geothermal fluid (SHGF) and magma reservoirs. An exemplary apparatus can include a well screen coupled to an end of a casing string. The well screen, which is at least partially submerged within an underground reservoir, defines a volume in the underground reservoir that can be filled with superhot geothermal fluid. A slidable casing is aligned coaxially with the well screen and configured to be repositioned relative to the well screen. A draw pipe extending through the slidable casing is configured to convey SHGF from the underground reservoir towards the surface in response to the slidable casing being repositioned to obstruct more of a set of apertures in the well screen and an increase in pressure within a cavity of the slidable casing.

The invention relates to the field of heat supply control, in particular to a terrestrial heat and solar energy coupling heat supply control method and system. The method comprises the following steps: acquiring heat supply load prediction data and solar radiation prediction data of a target area, dynamically formulating and executing pre-preparation operation of a cascade flash evaporation reactor based on the data, and generating a reactor dynamic preheating scheme set; on this basis, geothermal fluid is introduced into a fluid self-flashing chamber, geothermal fluid self-flashing triggered based on pressure drop is executed, and a primary basic flashing information set is generated; on this basis, the remaining liquid fluid is guided to an enhanced boiling flash chamber, contact type enhanced boiling flash operation triggered based on the significant temperature difference is executed, and a secondary enhanced flash information set is generated; on the basis, multi-parameter dynamic feedback of geothermal fluid flow, chamber pressure and heat storage release rate is collected, and a collaborative optimization heat supply control set is generated. In the multi-energy coupling heat supply process, the heat supply quality can be guaranteed.

The invention provides a method for determining in-situ composition of geothermal water, and belongs to the technical field of geothermal energy development. Geothermal water, geothermal gas and spring bloom or scale samples are collected, chemical composition analysis of the geothermal water, component analysis of the geothermal gas (including absolute content of CO2 and H2S) and mineral composition analysis of the spring bloom or scale are carried out, and then according to the geochemical process of mother geothermal fluid rising from a deep reservoir to the earth surface, the geothermal gas is analyzed. And determining whether cold water mixing, gas escape and mineral precipitation occur in the geothermal water, finally correcting the influence of the generated geochemical action on the chemical components of the geothermal water, and calculating the chemical components of the in-situ geothermal fluid. According to the invention, the problem that the scaling property, corrosivity and thermal storage temperature evaluation of the thermal storage fluid are inaccurate due to the fact that the chemical composition of the mother geothermal fluid cannot be represented due to the geochemical effect of changing the composition of the existing surface thermal spring water or borehole geothermal well water in the upflow process can be solved.

A geothermal power system generates electricity using a geothermal fluid. The geothermal fluid is produced from, and then injected into, fractures in a subterranean formation such that pressures inside the fractures are maintained between the corresponding closure pressures propagation pressures of the fractures. In some aspects, the fractures are devoid of proppant, and are maintained open by the pressure of the fluid within the fractures.

The invention discloses a multi-energy co-production system based on geothermal energy and LNG cold energy. The multi-energy co-production system comprises a geothermal dual-ORC power generation module and an LNG cold energy comprehensive utilization module. The geothermal dual-ORC power generation module comprises a first power generation cycle and a second power generation cycle, working medium fluid of the first power generation cycle absorbs heat of geothermal fluid for power generation, and working medium fluid of the second power generation cycle absorbs heat of the working medium fluid of the first power generation cycle for power generation. And the LNG cold energy comprehensive utilization module is used for generating power by using heat energy of the working medium fluid of the second power generation cycle, and is used for re-heating natural gas by using heat of the geothermal fluid used by the first power generation cycle for subsequent use. The method has the advantage of improving the energy utilization rate.

Methods and systems are disclosed herein. A method may include operating a closed-loop geothermal system (100) disposed in a well (101). The well (101) includes a wellbore (102) penetrating the geothermal heat source (104), a casing string (120), a control valve (125), and a temperature sensor (127). An annulus (107) is formed between the closed-loop geothermal system (100) and the casing string (120). The method includes measuring, using the temperature sensor (127) a first temperature of the geothermal fluid. The method includes opening, when the first temperature is lower than a first predetermined temperature, the control valve (125) in order to discharge geothermal fluid from the annulus (107).

The invention relates to the technical field of hydrogen production, in particular to a waste organic matter hydrogen development system under deep high-temperature geothermal energy, which comprises a deep stratum heat storage and temperature control unit, the deep stratum heat storage and temperature control unit comprises a heat storage shell, a geothermal fluid circulation pipeline and an electric auxiliary heating module, and the heat storage shell is made of a high-temperature-resistant composite geological material; collected geothermal fluid is conveyed through a geothermal fluid circulation pipeline in the deep stratum heat storage and temperature control unit, and a stable high-temperature field at the temperature of 400-600 DEG C is maintained in cooperation with an electric auxiliary heating module. According to the development system and method, the stable high-temperature field at the temperature of 400-600 DEG C is maintained through the geothermal fluid circulation pipeline and the electric auxiliary heating module through the deep stratum heat storage and temperature control unit; geothermal resources serve as a main heat source, energy consumption is reduced by 30%-40% compared with a traditional process, the U-shaped reaction unit is covered with the thermal stress buffer layer, the thermal stress buffer layer is made of a memory alloy and flexible ceramic composite material, and the rigidity can be automatically adjusted along with thermal stress.

The utility model relates to the technical field of energy exploitation, and discloses a desander for geothermal well drilling, which comprises a charging barrel, a sealing cover is arranged on the upper surface of the charging barrel, a feeding pipe is arranged in the middle of the upper surface of the sealing cover, and a throttling component is arranged on the lower surface of the charging barrel. The movable block can be driven to move in the auxiliary groove through the electric push rod, when the movable block moves, the movable block can drive the flow baffle to move together, the exposed area of the conical discharge port can be adjusted through movement of the flow baffle, underground hot water can flow out through the conical discharge port at the moment, and the larger the exposed area of the conical discharge port is, the larger the discharge flow is. According to the underground hot water filtering device, personnel can adjust the flow and the flow speed of underground hot water in time according to actual working requirements, so that solid particles in the hot water are more effectively intercepted, filtering holes of the second-stage filtering net are smaller, the solid particles in geothermal fluid filtered by the first-stage filtering net can be secondarily screened, and the filtering effect on the solid particles is ensured.

The invention relates to the technical field of geothermal fluid water-vapor separation, and discloses a geothermal well high-temperature geothermal fluid sample water-vapor separation device and method.The geothermal well high-temperature geothermal fluid sample water-vapor separation device comprises a shell and a bottom plate, the bottom plate is arranged on one side of the shell, the front side of the shell is fixedly connected with a feeding pipe, and the top of the shell is fixedly connected with a box. Through the design of the gas collecting mechanism, after geothermal fluid passing through the interior of the shell is subjected to water vapor separation, separated gas enters the detachable gas storage units, the detachable gas storage unit at the tail end can be expanded firstly, and after the detachable gas storage unit on the edge side is expanded to the maximum value, the detachable gas storage unit at the tail end can be expanded to the maximum value. After the valve, facing one end of the detachable gas storage unit, of the adjacent detachable gas storage unit can be closed, the detachable gas storage unit on the outermost side can be taken down and replaced, and in the replacement process, the whole separation work of the device does not need to be closed, and the other detachable gas storage units can continue to store gas, so that the separation efficiency is guaranteed; and the detachable gas storage units are relatively light in weight, so that more labor is saved in the carrying process of workers.

The present disclosure relates to systems and methods for geothermal energy systems utilizing underground geothermal fluid transmission and distribution pipelines. In some examples, underground geothermal fluid transmission and distribution pipelines may be installed with underground expansion loops and a central anchor block that allows for controlled thermal expansion without exceeding the strength of the pipe material used for the pipelines.

The invention relates to the technical field of comprehensive utilization of clean energy, and discloses a thermal power generation cascade heat exchange method and system based on geothermal preheating, and the method comprises the following steps: S1, extracting geothermal fluid of which the temperature is greater than or equal to 120 DEG C, and preheating boiler feed water of a thermal power generation system to 120-160 DEG C by using the geothermal fluid; s2, the terrestrial heat tail water obtained after boiler feed water preheating in the step S1 is fed into an evaporator of an organic Rankine cycle system so as to drive an organic working medium to generate electricity; s3, the cooling water side of a condenser of the organic Rankine cycle system and the cooling water side of a condenser of the thermal power generation system are connected in parallel and connected into the same cooling tower for heat dissipation; and S4, conveying heat discharged by the organic Rankine cycle system to a thermally driven absorption tower of a carbon capture system for amine liquid regeneration. The invention aims to realize the coupling of fuel saving, efficiency improvement and carbon emission reduction; efficiency loss generated in the thermal power peak regulation process is compensated through terrestrial heat, and the overall energy utilization efficiency can be guaranteed.

The invention discloses a method for calculating the total heat loss of geothermal fluid in the flowing process of a geothermal shaft. According to the method, the influence of phase change heat transfer and fouling heat resistance on the total heat loss of the geothermal fluid is considered at the same time. The result shows that the total heat loss is gradually increased along with the shallow depth of the geothermal shaft, and once the geothermal fluid is flashed, the total heat loss is rapidly increased. In addition, according to an energy conservation equation, the total heat loss of the geothermal fluid is mainly divided into three parts which are respectively caused by specific enthalpy, kinetic energy and potential energy. The calculation result can deduce that the specific enthalpy is the main reason causing the total heat loss, and the change trend of the specific enthalpy is basically consistent with the total heat loss. The calculation result is mainly used for revealing main factors causing the total heat loss of the geothermal fluid, the total heat loss of the geothermal fluid is reduced by improving a shaft structure, a geothermal exploitation mode and other measures, and finally the overall utilization efficiency of geothermal energy is improved.

The present invention relates to an adsorbent for lithium extraction, its preparation method and application, belonging to the field of material technology. First, a precursor solution is prepared; then, a spinel-type lithium magnesium aluminum oxide is prepared; finally, an adsorbent for high-temperature lithium extraction is obtained. The adsorbent of the present invention can achieve efficient adsorption of lithium ions in geothermal fluid. At about 80 °C, the saturated adsorption capacity of this adsorbent for Li + is greater than 40 mg / g, and the saturated adsorption capacity is greater than 35 mg / g after 30 cycles of reuse.

The invention relates to the technical field of geothermal gas collection, in particular to a high-temperature geothermal fluid sampling device and method. The sampling device comprises a sampling unit, a monitoring unit and a gas collecting unit, wherein the sampling unit comprises a gas collecting hood, a movable rod piece, a waterproof breathable film and a transmission pipeline; the monitoring unit comprises a temperature sensor, a gas flowmeter and a film gauge; the gas collection unit comprises a tail gas collector, a sampler and a power source. The sampling device is simple in overall structure and good in sealing performance, and is provided with a power source, so that the sampling requirements of different types of samples can be met, and the sampling efficiency can be improved on the basis of ensuring the sampling purity. The sampling method is simple to operate, and the accuracy of the sample collection time is improved by innovating a sampling time calculation formula.