Energy and temperature management system and method for whole process of injection and production of superficial ultra-heavy oil

Abstract

The invention provides an energy and temperature management system and method for the whole process of injection and production of shallow ultra-heavy oil, the energy and temperature management system in the steam injection process designs the lowest heating temperature of an oil reservoir and the energy demand corresponding to the periodic steam injection development radius, designs the lowest steam parameter at the bottom of a well, and monitors the steam parameters of a wellhead and a ground pipeline inlet in real time; the outlet parameters of the boiler are controlled to meet the lowest steam injection requirement of the oil reservoir; in the production process, the oil reservoir and produced fluid energy and temperature management system monitors the wellhead temperature and flow, analyzes to obtain the well bottom oil reservoir temperature, judges whether to continue production or turn round according to the well bottom oil reservoir temperature, and ensures that the produced fluid temperature in the production process is greater than the flowing temperature, so that the produced fluid is smoothly conveyed from the oil reservoir to a shaft and then to a united station. Ineffective energy heat loss of an oil layer is reduced, the effectiveness of oil reservoir injection energy is brought into full play, and an efficient development mode of quick injection and quick production of superficial ultra-heavy oil is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of enhanced oil recovery in thermal recovery of heavy oil, and particularly to an energy and temperature management system and method for the whole process of injection and production of shallow extra-heavy oil. Background Art

[0002] The basic principle of developing heavy oil by steam huff and puff is to develop heavy oil by the action of heat. Heavy oil is sensitive to temperature. Whether in the reservoir, wellbore or surface pipeline transportation process, as long as the temperature of the crude oil is ensured to reach the temperature requirement for crude oil flow, the crude oil in the reservoir can flow smoothly to the bottom of the well, lift smoothly along the bottom of the well to the wellhead, and be transported by the surface pipeline at the wellhead to the central processing facility for treatment and external transportation.

[0003] In the western oil area of Shengli Oilfield, such as Block Haqian 1 in Chunhui Oilfield and Alade Oilfield, the reservoir is shallowly buried, the formation temperature is only 23°C, and the viscosity of the formation crude oil is greater than 100×10 4 mPa·s. Only the steam huff and puff method can be used for production. Extra-heavy oil has extremely strong temperature sensitivity, and the crude oil flow has strict requirements for temperature. During the production process, due to the low formation temperature, it is difficult for the crude oil to flow to the bottom of the well; due to the low wellbore temperature, effective lifting cannot be achieved; due to the low temperature of the surface oil pipeline, high pipeline back pressure, wall hanging and blockage and other phenomena also seriously affect the oil transportation effect. Only when each node from the oil layer to the wellbore and even the surface pipeline is unblocked can the normal operation of the entire oil production system be ensured. During the steam injection process, based on the flow conditions of the formation crude oil, sufficient energy is required to heat the formation crude oil so that the crude oil can reach the bottom of the well smoothly. The steam at the boiler outlet needs to pass through the heat loss of the surface steam pipeline and the wellbore steam injection pipeline to ensure that the energy or temperature finally reaching the bottom of the well meets the requirements of the reservoir energy. Therefore, how to manage the temperature of the steam injection system and the production system is the key to the development of shallow extra-heavy oil.

[0004] How to ensure that the steam heat / temperature at the bottom of the well raises the temperature of the crude oil within the effective radius of the reservoir above the flowing temperature, so that the crude oil can flow smoothly to the bottom of the well is the primary problem in developing extra-heavy oil. To achieve the steam heat / temperature at the bottom of the well, it is necessary to manage the steam injection link in the wellbore and the steam transportation link on the ground, and finally put forward requirements for the outlet parameters of the boiler. The heat of steam is reflected by two parameters: temperature and dryness. The higher the temperature and dryness of the steam, the stronger the working ability of the steam. Managing the steam parameters is to reduce the heat loss in the whole process from the boiler outlet to the bottom of the well. Fundamentally, it is to manage the temperature of the steam well. Therefore, the essence of the thermal recovery process of extra-heavy oil is to manage the temperature of steam and produced fluid well, so as to improve the thermal recovery efficiency.

[0005] In the Chinese patent application with the application number: CN201711181127.8, it involves a method for estimating the steady-state operation status of a steam heating pipeline considering a hydrophobic model, belonging to the technical field of the operation and control of integrated energy systems. First, the steam heating pipeline and the steam trap are equivalent to two pipelines, and a Γ-type equivalent model of the steam heating pipeline considering the hydrophobic model is established. Then, an objective function for estimating the steady-state operation status of the steam heating pipeline considering the hydrophobic model is established, and the steady-state operation status of the steam heating pipeline is estimated according to the objective function. The method of the present invention considers the hydrophobic phenomenon caused by the condensation of part of the steam in the steam heating pipeline, can effectively monitor the operation status of the steam heating pipeline, give a quantitative estimate of the amount of hydrophobic water, complete the measurement under the non-full measurement configuration, identify bad data, and provide detailed data support for the energy management system and the dispatching management system.

[0006] In the Chinese patent application with the application number: CN202010239940.1, it involves a calculation method for the actual heat consumption of a heavy oil steam stimulation reservoir. The calculation method for the actual heat consumption of the heavy oil steam stimulation reservoir includes: Step 1, measure the bottom hole temperature and calculate the temperature of the heating zone near the bottom hole; Step 2, measure the steam injection temperature at the wellhead and calculate the total heat enthalpy of the steam injection at the wellhead; Step 3, calculate the heat loss of the wellbore according to the thermal insulation material of the wellbore; Step 4, measure the temperature of the produced fluid, the oil production and the water production, and calculate the increased heat enthalpy of the produced fluid; Step 5, estimate the heat loss of the top, bottom and cover layers; Step 6, calculate the actual heat consumption of the reservoir in this cycle. The calculation method for the actual heat consumption of the heavy oil steam stimulation reservoir provides a fast, simple and effective method for on-site technical personnel to judge the quality of cyclic steam injection, the heat utilization rate of the reservoir, and the evaluation of the cyclic development effect, and provides a basis for reservoir managers to macroscopically grasp the cyclic stimulation development law and carry out macro development decisions.

[0007] In the Chinese patent application with the application number: CN201510837567.9, it involves a method and device for obtaining the wellbore temperature field of a hot water circulation heating viscosity reduction process. Among them, the method includes: determining data parameters; using the data parameters to obtain the formation thermal resistance, cement sheath thermal resistance, casing wall thermal resistance, heat convection thermal resistance between the liquid and the inner wall of the casing, heat convection thermal resistance between the air and the inner wall of the casing, heat conduction thermal resistance between the inner and outer walls of the tubing, heat convection thermal resistance between the crude oil and the inner wall of the tubing, heat convection thermal resistance between the inner and outer walls of the hollow rod, heat convection thermal resistance between the hot fluid and the inner wall of the hollow rod, heat convection thermal resistance between the inner and outer walls of the inner pipe, and heat convection thermal resistance between the hot fluid and the inner pipe; using the thermal resistance information to determine the radial heat loss per unit length of the wellbore unit; using the radial heat loss per unit length of the wellbore unit to determine the hot water temperature field of the inner pipe, the hot water temperature field of the hollow rod, and the temperature field of the crude oil in the tubing under the conditions of forward injection and / or reverse injection.

[0008] The above prior arts are quite different from the present invention and fail to solve the technical problems we want to address. Therefore, we have invented a new energy and temperature management system and method for the entire process of injecting and producing shallow extra - heavy oil. Summary of the Invention

[0009] The object of the present invention is to provide an energy and temperature management system for the entire process of injecting, producing, and transporting fluids in the steam injection thermal recovery process of shallow extra - heavy oil reservoirs, which establishes a management system for the energy and temperature of fluids in the entire process of injection, production, and transportation, and forms an energy and temperature management system and method for the entire process of injecting and producing shallow extra - heavy oil for the energy and temperature management of fluids in the entire process of injection, production, and transportation.

[0010] The object of the present invention can be achieved by the following technical measures: An energy and temperature management system for the entire process of injecting and producing shallow extra - heavy oil. This energy and temperature management system for the entire process of injecting and producing shallow extra - heavy oil includes an energy and temperature management system for the steam injection process, an energy and temperature management system for the reservoir and produced fluid during the production process. The energy and temperature management system for the steam injection process designs the minimum heating temperature of the reservoir and the energy requirements corresponding to the cyclic steam injection development radius, designs the minimum steam parameters at the bottom of the well, real - time monitors the steam parameters at the wellhead and the inlet of the surface pipeline, and controls the outlet parameters of the boiler to meet the minimum steam injection requirements of the reservoir; The energy and temperature management system for the reservoir and produced fluid during the production process monitors the wellhead temperature and flow rate, analyzes to obtain the reservoir temperature at the bottom of the well, determines whether to continue production or switch cycles based on the reservoir temperature at the bottom of the well, and ensures that the temperature of the produced fluid during the production process is greater than the flowing temperature to achieve the smooth transportation of the produced fluid from the reservoir through the wellbore to the gathering station.

[0011] The object of the present invention can also be achieved by the following technical measures:

[0012] The energy and temperature management system for the steam injection process includes an oil - layer flowing temperature processing unit and an oil - reservoir steam parameter analysis unit. The oil - layer flowing temperature processing unit is connected to the oil - reservoir steam parameter analysis unit, collects the ground viscosity data μ of the crude oil in the development well, and designs the minimum flowing temperature T of the oil layer based on the ground viscosity data μ 流动 . The oil - reservoir steam parameter analysis unit collects the initial temperature t of the oil reservoir zw , sets the effective heating radius r, and designs the minimum steam temperature t at the bottom of the well based on the minimum flowing temperature T of the oil layer 流动 and the minimum heat injection rate H sw . W .

[0013] The energy and temperature management system for the steam injection process also includes a bottom - hole steam parameter monitoring and analysis unit. The bottom - hole steam parameter monitoring and analysis unit is connected to the oil - reservoir steam parameter analysis unit. Based on the minimum steam temperature t sw and the minimum heat injection rate H W , it designs the bottom - hole steam parameters, including the steam injection rate G and the steam pressure Psw 、Steam quality x w 。

[0014] The energy and temperature management system for the steam injection process further includes a wellhead steam parameter monitoring and analysis unit and a steam parameter monitoring and analysis unit at the inlet of the surface steam transmission pipeline. The wellhead steam parameter monitoring and analysis unit and the steam parameter monitoring and analysis unit at the inlet of the surface steam transmission pipeline monitor the steam parameters at the wellhead and the inlet of the surface pipeline in real time. The wellhead steam parameter monitoring and analysis unit predicts the lowest steam parameters at the wellhead based on the designed steam parameters at the bottom of the well and the heat loss in the wellbore; the steam parameter monitoring and analysis unit at the inlet of the surface steam transmission pipeline predicts the lowest inlet steam parameters of the surface pipeline based on the heat loss of the surface pipeline.

[0015] The energy and temperature management system for the steam injection process further includes a steam parameter command transceiver unit and a boiler outlet parameter control system. The steam parameter command transceiver unit is connected to the steam parameter monitoring and analysis unit at the bottom of the well, the wellhead steam parameter monitoring and analysis unit, and the steam parameter monitoring and analysis unit at the inlet of the surface steam transmission pipeline. When any one of the steam parameters at the bottom of the well, the wellhead steam parameters, and the pipeline inlet steam parameters is lower than the lowest design parameter, the steam parameter command transceiver unit receives and sends commands to the boiler outlet parameter control system to control the outlet parameters of the boiler to meet the minimum steam injection requirements of the reservoir and achieve efficient steam injection in the reservoir.

[0016] The energy and temperature management system for the steam injection process further includes a steam injection terminal processing unit. The steam parameter command transceiver unit is connected to the boiler outlet parameter control system and the steam injection terminal processing unit. The steam injection terminal processing unit receives the information of the total steam injection volume and stops steam injection and switches to the next cycle when the designed steam injection time is reached.

[0017] The energy and temperature management system for the reservoir and produced fluid during the production process includes a wellhead produced fluid temperature and flow monitoring unit, a bottom-hole produced fluid temperature processing unit, a reservoir and produced fluid temperature command transceiver control unit, and a production control system. The wellhead produced fluid temperature and flow monitoring and processing unit monitors the wellhead temperature and flow and provides the data to the bottom-hole produced fluid temperature processing unit. The bottom-hole produced fluid temperature processing unit analyzes to obtain the reservoir temperature at the bottom of the well, transmits the reservoir temperature at the bottom of the well to the reservoir and produced fluid temperature command transceiver control unit, and is transmitted by the reservoir and produced fluid temperature command transceiver control unit to the production control system. The production control system determines whether to continue production or switch to the next cycle based on the reservoir temperature at the bottom of the well.

[0018] The reservoir and produced fluid energy and temperature management system for this production process further includes a wellbore produced fluid temperature monitoring unit, an oil pipeline produced fluid temperature monitoring and analysis unit, a wellbore electric heating control unit, and a surface pipeline electric heating control unit. The temperatures at various points in the wellbore and the surface oil pipeline obtained by monitoring and analyzing by the wellbore produced fluid temperature monitoring unit and the oil pipeline produced fluid temperature monitoring and analysis unit are transmitted to the reservoir and produced fluid temperature command transceiver and control unit. When the wellbore temperature is lower than the flowing temperature T 流动 , the reservoir and produced fluid temperature command transceiver and control unit sends a command to the production control system to start the wellbore electric heating control unit to start heating up the wellbore; when the temperature of the surface oil pipeline is lower than the flowing temperature T 流动 , the reservoir and produced fluid temperature command transceiver and control unit sends a command to the production control system to start the surface pipeline electric heating control unit to start heating up the pipeline.

[0019] The reservoir and produced fluid energy and temperature management system for this production process further includes a joint station and a shutdown and cycle conversion command transceiver unit. The wellbore electric heating control unit judges the wellbore heating depth Z H and designs the wellbore heating power N 1 to implement wellbore heating and temperature increase. The surface pipeline electric heating control unit judges the pipeline heating depth l H and designs the wellbore heating power N 2 to implement pipeline heating and temperature increase. The joint station processes the produced fluid. When the bottom-hole produced fluid temperature is lower than the flowing temperature T 流动 , the shutdown and cycle conversion command transceiver unit sends a shutdown command to the reservoir flowing temperature processing unit to enter the steam injection link of the next cycle.

[0020] The object of the present invention can also be achieved by the following technical measures: an energy and temperature management method for the steam injection process. The energy and temperature management method for the steam injection process adopts an energy and temperature management system for the whole process of shallow ultra-heavy oil injection and production, including:

[0021] Step 1: Use the reservoir flowing temperature processing unit to collect the crude oil viscosity, establish the flow correspondence relationship between the heavy oil viscosity and temperature, and clarify the flowing temperature T 流动 ;

[0022] Step 2: Use the reservoir steam parameter analysis unit to collect the reservoir temperature, design the heating radius, and predict the lowest bottom-hole steam temperature t sw and the heat injection rate Hw;

[0023] Step 3: Use the bottom-hole steam parameter monitoring and analysis unit to collect the bottom-hole steam parameters. The bottom-hole steam parameter monitoring and analysis unit judges whether the bottom-hole heat injection rate Hw and the steam temperature t sw meet the heating radius requirements;

[0024] Step 4: Send instructions to the boiler outlet parameter control system through the steam parameter instruction transceiver unit to adjust the boiler parameters;

[0025] Step 5: Use the wellhead steam parameter monitoring and analysis unit to collect wellhead steam parameters and determine whether the minimum bottom-hole heat injection rate meets the design requirements;

[0026] Step 6: Use the steam parameter monitoring and analysis unit at the inlet of the surface steam pipeline to collect pipeline inlet steam parameters and determine whether the pipeline heat loss is lower than the design value;

[0027] Step 7: When the injection parameters at the injection terminal meet the design requirements for the heating radius, stop the injection, complete the temperature and energy management from the boiler to the bottom hole, and transfer to production operation management.

[0028] The object of the present invention can also be achieved by the following technical measures:

[0029] In step 1, the reservoir flow temperature processing unit collects the ground viscosity data μ of the crude oil in the development well o , and the calculation formula (1) provides the corresponding relationship between the crude oil viscosity μ of heavy oil with different viscosities o and the flow temperature T 流动 , and T 流动 is simultaneously used as the minimum heating temperature of the reservoir:

[0030] T 流动 = 9.7266×ln(0.97μ o ) - 35.093 (1).

[0031] In step 2, collect the initial reservoir temperature t zw , and the reservoir steam parameter analysis unit designs an effective heating radius r of the reservoir for a huff and puff cycle, requiring that the reservoir temperature Tr within the effective heating radius r ≥ T 流动 ; determine the bottom-hole heat injection rate and the steam temperature entering the reservoir according to r and T 流动 .

[0032] In step 3, use the reservoir steam parameter analysis unit to establish the requirements for the minimum steam parameters at the bottom hole for the heating radius and the heating temperature T 流动 , including the injection rate G, the steam temperature t sw , and the steam dryness x w . When the bottom-hole heat injection rate and the steam temperature meet the heating radius requirements, maintain the current injection status. When they do not meet the heating radius requirements, enter step 4.

[0033] In step 4, send instructions to the boiler outlet parameter control system through the steam parameter instruction transceiver unit to adjust the boiler outlet parameters and increase one or more steam parameters at the boiler outlet to achieve the target values.

[0034] In step 5, the wellhead steam parameter monitoring and analysis unit is used to collect the wellhead steam parameters, and the minimum wellhead steam parameters are inversely deduced based on the minimum heat injection rate at the bottom of the well and the bottom-hole steam temperature; the wellhead steam parameter monitoring and analysis unit determines whether the wellhead steam parameters meet the design requirements; if not, it indicates that the wellhead steam parameters do not meet the standards, and the process proceeds to step 4; if they meet the requirements, the process proceeds to step 6.

[0035] In step 6, the steam parameter monitoring and analysis unit at the inlet of the surface steam transmission pipeline is used to collect the pipeline inlet steam parameters, i.e., the boiler outlet steam parameters, and the minimum steam parameters H at the inlet of the designed injection pipeline, i.e., the boiler outlet, are inversely deduced based on the wellhead injection parameters and the heat insulation condition of the surface pipeline 锅炉 and the minimum heat loss of the pipeline; the steam parameter monitoring and analysis unit at the inlet of the steam transmission pipeline determines whether the pipeline heat loss is lower than the design value; if it is not lower than the design value, it indicates that the heat loss is large and the boiler outlet parameters are low, and the process proceeds to step 4; if it is lower than the design value, the process proceeds to step 7.

[0036] In step 7, when the injection volume reaches the design requirements, the injection steam terminal processing unit stops the steam injection. The designed injection volume is the basis for periodic injection stoppage. At this time, the temperature and energy management from the boiler to the bottom of the well for one cycle of the steam injection process is completed; it enters the temperature and energy management subsystem in the production stage.

[0037] The object of the present invention can also be achieved by the following technical measures: a temperature and energy management method in the production stage, which adopts an energy and temperature management system for the whole process of shallow extra-heavy oil injection and production, including:

[0038] In step 21, the wellhead produced liquid temperature and flow monitoring unit is used to collect the wellhead temperature;

[0039] In step 22, the bottom-hole produced liquid temperature t is inversely deduced w , and it is judged whether t w ≥T 流动 ;

[0040] In step 23, the produced liquid temperature monitoring unit in the wellbore is used to collect the temperature along the wellbore, and it is judged whether at any monitoring point t z ≥T 流动 ;

[0041] In step 24, an instruction is sent to the production control system through the reservoir and produced liquid temperature instruction transceiver and control unit to start the wellbore electric heating viscosity reduction process;

[0042] In step 25, the produced liquid temperature monitoring and analysis unit for the oil transmission pipeline is used to collect the temperature along the surface pipeline, and it is judged whether at any monitoring point t lh ≥T 流动 ;

[0043] Step 26: Send an instruction to the production control system through the reservoir and produced fluid temperature instruction transceiver control unit to start the pipeline electric heating viscosity reduction process;

[0044] Step 27: When the temperature t at any monitoring point in the wellbore and pipeline z / t lh ≥T 流动 carry out production, realizing the smooth transportation of the produced fluid from the reservoir to the wellbore and then to the gathering station.

[0045] The object of the present invention can also be achieved by the following technical measures:

[0046] In step 22, the bottom-hole produced fluid temperature processing unit calculates the bottom-hole produced fluid temperature t 0 by backtracking from the collected wellhead produced fluid temperature t w ,t w obtained by the calculation formula (18). The bottom-hole produced fluid temperature t w reflects the reservoir temperature in the near-wellbore area at different production times;

[0047]

[0048] In the formula:

[0049] t 0 : The temperature of the produced fluid at the wellhead of the oil well, obtained by testing;

[0050] t w : The bottom-hole produced fluid temperature of the oil well, approximately equal to the reservoir temperature in the near-wellbore area;

[0051] K 1 : The heat transfer coefficient of the production well;

[0052] m: Low-temperature gradient;

[0053] W: The water equivalent of the produced fluid;

[0054] Z: Depth.

[0055] In step 22, determine whether t w ≥T 流动 is satisfied; the bottom-hole produced fluid temperature processing unit transmits the data to the reservoir and produced fluid temperature instruction transceiver control unit. If t w ≥T 流动 is not satisfied, the reservoir and produced fluid temperature instruction transceiver control unit sends a production stop and cycle change instruction to the production control system, and the production control system implements the production stop operation and waits to enter the next cycle of injection and production cycle; if t w ≥T 流动 is satisfied, the continuous production of the reservoir can be maintained; the process enters step 23.

[0056] In step 23, the wellbore produced fluid temperature monitoring unit is used to collect the wellbore temperature along the way and transmit the data to the reservoir and produced fluid temperature command transceiver control unit. The reservoir and produced fluid temperature command transceiver control unit determines whether t z ≥T 流动 is satisfied at any monitored wellbore position; if satisfied, normal production is carried out, and if not satisfied, the process proceeds to step 24.

[0057] In step 24, the reservoir and produced fluid temperature command transceiver control unit sends a command to the production control system. The production control system issues a command to the wellbore electric heating control unit to start the wellbore electric heating viscosity reduction process; the wellbore electric heating control unit adjusts the wellbore electric heating power N H infinitely according to the heating depth z 1 and the real-time monitored produced fluid data, ensuring that the produced fluid temperature t z >T 流动 along the entire wellbore length, so as to realize the smooth lifting of the fluid in the wellbore from the bottom of the well to the wellhead.

[0058] In step 25, the produced fluid temperature monitoring and analysis unit of the oil pipeline is used to collect the temperature of the oil pipeline along the ground and transmit the data to the reservoir and produced fluid temperature command transceiver control unit. The reservoir and produced fluid temperature command transceiver control unit determines whether t lH ≥T 流动 is satisfied at any monitored pipeline position; if satisfied, normal production is carried out, and if not satisfied, the process proceeds to step 26.

[0059] In step 26, the reservoir and produced fluid temperature command transceiver control unit sends a command to the production control system. The production control system issues a command to the ground pipeline electric heating control unit to start the ground oil pipeline electric heating viscosity reduction process; the ground pipeline electric heating control unit adjusts the oil pipeline electric heating power N 2 infinitely according to the heating length and the real-time monitored produced fluid data, ensuring that the produced fluid temperature t lH >T 流动 along the entire pipeline length, so as to realize the smooth pipeline transportation of the produced fluid from the wellhead to the gathering station.

[0060] In step 27, when the wellbore produced fluid temperature monitoring unit and the produced fluid temperature monitoring and analysis unit of the oil pipeline monitor that t z / t lH ≥T 流动 at any monitored position, normal production and transportation are maintained, realizing the smooth transportation of the produced fluid from the reservoir to the wellbore and then to the gathering station during the cyclic production process. At this time, the temperature and energy management from the reservoir to the wellbore and then to the gathering station during the cyclic production process is completed.

[0061] The energy and temperature management system and method for the whole process of injection and production of shallow extra - heavy oil in the present invention establish a fluid energy and temperature management system for the whole process of injection, production, and transportation in view of the temperature influencing factors of injection and production fluids during the steam injection thermal recovery process of shallow extra - heavy oil reservoirs, and form an energy and temperature management system and method for the whole process of injection and production of shallow extra - heavy oil with fluid energy and temperature management for the whole process of injection, production, and transportation.

[0062] The present invention establishes the corresponding relationship between crude oil viscosity and flowing temperature, clarifies the corresponding relationship between temperature and flow, and establishes the core indexes of temperature and energy management. Based on the bucket law, the present invention provides a systematic management method for the whole process of injection, production, and transportation of extra - heavy oil, utilizes the synergy effect of each node in the whole process of injection, production, and transportation, effectively avoids the short - board effect of difficult wellbore lifting and surface pipeline transportation, reduces the operation risk of pipeline blockage caused by thick oil, reduces the ineffective energy heat loss of the oil reservoir, gives full play to the effectiveness of the injected energy of the oil reservoir, and realizes the efficient development mode of fast injection and fast production of shallow extra - heavy oil. Brief Description of the Drawings

[0063] Figure 1 It is a structural diagram of a specific embodiment of the energy and temperature management system for the whole process of injection and production of shallow extra - heavy oil of the present invention;

[0064] Figure 2 It is the energy and temperature management method and flow chart for the steam injection process in a specific embodiment of the present invention;

[0065] Figure 3 It is the energy and temperature management method and flow chart for the production process in a specific embodiment of the present invention. Detailed Description of the Invention

[0066] It should be noted that the following detailed description is exemplary and is intended to provide further illustration of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs.

[0067] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular forms are also intended to include the plural forms. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they specify the presence of features, steps, operations, and / or combinations thereof.

[0068] The energy and temperature management system for the whole process of injection and production of shallow extra - heavy oil of the present invention consists of 2 subsystems, namely injection and production subsystems, as shown in Figure 1 : Subsystem 1 is the energy and temperature management system for the steam injection process, and Subsystem 2 is the energy and temperature management system for the oil reservoir and produced fluid during the production process.

[0069] Subsystem 1 consists of an oil reservoir flow temperature processing unit, an oil reservoir steam parameter analysis unit, a bottom-hole steam parameter analysis unit, a wellhead steam parameter monitoring and analysis unit, a ground steam transmission pipeline inlet steam parameter monitoring and analysis unit, a steam parameter command transceiver unit, a boiler outlet parameter control system, and an injection steam terminal processing unit. Subsystem 1 designs the minimum heating temperature of the oil reservoir and the energy requirement corresponding to the cyclic steam injection development radius through the oil reservoir flow temperature processing unit and the oil reservoir steam parameter analysis unit. The bottom-hole steam parameter analysis unit designs the minimum bottom-hole steam parameters based on the oil reservoir heating radius and heating temperature. The wellhead steam parameter monitoring and analysis unit and the ground steam transmission pipeline inlet steam parameter monitoring and analysis unit monitor the steam parameters at the wellhead and the ground pipeline inlet in real time to determine whether they can meet the designed minimum bottom-hole steam parameters. The boiler outlet parameters are controlled through the steam parameter command transceiver unit to meet the minimum steam injection requirements of the oil reservoir and achieve efficient steam injection in the oil reservoir.

[0070] Subsystem 2 consists of a wellhead produced fluid temperature and flow rate monitoring unit, a bottom-hole produced fluid temperature processing unit, a wellbore produced fluid temperature monitoring unit, an oil transmission pipeline produced fluid temperature monitoring and analysis unit, an oil reservoir and produced fluid temperature command transceiver and control unit, a production control system, a wellbore electric heating control unit, a ground pipeline electric heating control unit, a combined station terminal processing unit, a production stop and cycle conversion command transceiver unit, and an oil reservoir flow temperature processing unit. Subsystem 2 monitors the wellhead temperature and flow rate through the wellhead produced fluid temperature and flow rate monitoring and processing unit and provides the data to the bottom-hole produced fluid temperature processing unit. The bottom-hole produced fluid temperature processing unit analyzes to obtain the bottom-hole oil reservoir temperature and transmits it to the oil reservoir and produced fluid temperature command transceiver and control unit. The production control system determines whether to continue production or convert the cycle based on the bottom-hole oil reservoir temperature. The bottom-hole temperature is transmitted to the oil reservoir and produced fluid temperature command transceiver and control unit based on the temperatures at various points obtained from the wellbore produced fluid temperature monitoring unit and the oil transmission pipeline produced fluid temperature monitoring and analysis. The production control system determines whether to start heating to increase temperature and reduce viscosity. Subsystem 2 realizes the efficient lifting and transportation of crude oil in the oil reservoir during the high-temperature potential development period of the oil reservoir. After the development potential is exhausted, it promptly converts the cycle to achieve the efficient development of shallow extra-heavy oil.

[0071] Subsystem 1 and Subsystem 2 form a closed loop in the oil reservoir flow temperature processing unit to complete the energy and temperature management of the entire injection-production process of a shallow extra-heavy oil huff and puff cycle.

[0072] The present invention establishes an energy and temperature management method for the injection, production, and transportation system nodes. The energy and temperature management method for the injection, production, and transportation system nodes includes the energy and temperature management method and process during the steam injection process as shown in Figure 2 , and the energy and temperature management method and process during the production process as shown in Figure 3 .

[0073] In step 101, the oil reservoir flowing temperature processing unit collects the ground viscosity data μ of the crude oil from the development well o , and the calculation formula (1) provides the crude oil viscosity μ of heavy oil with different viscosities o and the corresponding relationship with the flowing temperature T 流动 , and T 流动 is simultaneously used as the minimum heating temperature of the oil reservoir:

[0074] T 流动 -9.7266×ln(0.97μo)-35.093 (1)

[0075] The error between the calculated temperature and the measured temperature is controlled within ±5%, fully meeting the requirements of the engineering working conditions. The process enters step 102

[0076] In step 102, the oil reservoir steam parameter analysis unit is used to collect the initial temperature t of the oil reservoir zw , and an effective heating radius r of the oil reservoir for a huff and puff cycle is designed, requiring that the oil reservoir temperature Tr within the effective heating radius r is ≥ T 流动 . Based on r and T 流动 the bottom-hole heat injection rate and the steam temperature entering the oil reservoir are determined. The determination method is as follows:

[0077] The oil reservoir temperature Tr corresponding to the effective heating radius r is calculated by the calculation formula (2), and thus the corresponding relationship between the effective heating radius r, the oil reservoir temperature Tr, and the flowing temperature T 流动 is established:

[0078]

[0079] From the calculation formula (2), the calculation formula (3) is deduced, and the minimum requirement of the oil reservoir temperature Tr within the effective heating radius r for the bottom-hole steam temperature t sw is established:

[0080]

[0081] In the formula:

[0082] Tr: The oil reservoir temperature corresponding to the heating radius r, °C;

[0083] t sw : The steam temperature at the bottom hole or in the oil reservoir, °C;

[0084] t zw : The initial temperature of the oil reservoir, °C;

[0085] r: The effective heating radius, m.

[0086] R case : The thermal resistance of the casing, (m.°C) / m;

[0087] R: Total thermal resistance of the heat injection system, (m·℃) / m.

[0088] Tr, r, t sw A one-to-one correspondence is formed. First, the bottom-hole steam temperature t must be ensured. sw , and secondly, ensure that Tr ≥ T 流动 , so as to ensure that the extra-heavy oil within the radius r can be smoothly produced.

[0089] The effective heating radius r is achieved by the energy injected into the oil reservoir. Through the calculation formula (4), the corresponding relationship between the heating radius r and the reservoir injection energy H W is established as follows:

[0090]

[0091] In the formula:

[0092] H w ——Bottom-hole heat injection rate, w;

[0093] h——Perforated oil layer thickness, m;

[0094] β——Heat capacity ratio of the bottom and top covers Dimensionless;

[0095] F(x)——Dimensionless time function,

[0096]

[0097] t D Dimensionless time,

[0098] α——Formation thermal diffusivity, m 2 / h;

[0099] r——Injection time, h;

[0100] erfc(X)——Complementary error function,

[0101] λ s ——Rock thermal conductivity, w / (m·K);

[0102] For the corresponding heating radius r, the bottom-hole heat injection rate H W must satisfy:

[0103]

[0104] The process enters step 103.

[0105] In step 103, using the bottom-hole steam parameter analysis module, the corresponding relationship between the heating radius and the heating temperature T 流动The requirements for the lowest steam parameters at the bottom of the well, including the steam injection rate G, steam temperature t sw , steam quality x w , etc. The establishment method is as follows:

[0106] The heat injection rate H at the bottom of the well W can be calculated through the bottom hole temperature t sw , and thus the heat injection rate H at the bottom of the well is obtained W and the corresponding relationship with the bottom hole temperature t sw is shown in calculation formula (6):

[0107] H w = G(i w + r w x w - i z ) (6)

[0108] The enthalpy i of saturated water w is calculated by calculation formula (7):

[0109]

[0110] The latent heat of vaporization r w is calculated by calculation formula (8):

[0111]

[0112] The enthalpy i of water corresponding to the reservoir temperature t zw is calculated by calculation formula (9): z i

[0113] i z = 1.712842383×t zw (9)

[0114] The steam injection parameters at the bottom of the well or in the reservoir, including the steam injection rate G, steam temperature t sw , steam quality x w Judgment formula (10):

[0115]

[0116] Judge whether the heat injection rate of bottom hole steam and the steam temperature meet the requirements of the heating radius r. If it is satisfied, it means that the bottom hole steam parameters meet the standards and the current steam injection status can be maintained. If it is not satisfied, the process enters step 104.

[0117] In step 104, send an instruction to the boiler outlet parameter control system through the steam parameter instruction transceiver unit to adjust the boiler outlet parameters (steam injection rate, dryness, etc.) to increase one or more steam parameters at the boiler outlet to achieve the target value. The process enters step 105.

[0118] In step 105, the wellhead steam parameter monitoring and analysis unit is used to collect the wellhead steam parameters, and the minimum wellhead steam parameters are inversely deduced based on the minimum heat injection rate at the bottom of the well and the bottom-hole steam temperature. The inverse deduction method is as follows: Combining the heat transfer conditions of the steam injection string in the wellbore, the minimum wellhead heat injection rate H at the wellhead is inversely deduced from the calculation formula (11) o :

[0119]

[0120] In the formula:

[0121] t s0 : Wellhead steam temperature, °C;

[0122] t sw : Bottom-hole steam temperature, °C;

[0123] K 2 : Heat transfer coefficient of the steam injection pipeline in the wellbore, w / (m·°C);

[0124] The corresponding relationship between the wellhead heat injection rate H o and the wellhead temperature t so is obtained from formula (12):

[0125] H o = G(i o + r o x o ) (12)

[0126] Saturated water i o is calculated by the calculation formula (13):

[0127]

[0128] The latent heat of vaporization r w is calculated by the calculation formula (14):

[0129]

[0130] The calculation formula (15) establishes the corresponding relationship between the wellhead steam parameters and the bottom-hole steam parameters, ensuring that:

[0131]

[0132] the requirements for the steam heat and temperature of the effective heating radius r can be met.

[0133] Judge whether the wellhead steam parameters meet the design requirements. If not, it means that the wellhead steam parameters do not meet the standards, and the process enters step 104. If they meet, the process enters step 106.

[0134] In step 106, the ground steam injection pipeline inlet steam parameter monitoring and analysis unit is used to collect the pipeline inlet steam parameters, i.e., the boiler outlet steam parameters, and based on the wellhead steam injection parameters and the heat insulation condition of the ground pipeline, the lowest steam parameter H at the inlet of the designed injection pipeline, i.e., the boiler outlet, is deduced backwards. 锅炉 And the lowest heat loss of the pipeline, the derivation method is as follows:

[0135] First, based on the wellhead heat injection rate H o , the pipeline inlet steam parameter, i.e., the boiler outlet heat injection rate H, is deduced backwards from the calculation formula (16). 锅炉 :

[0136]

[0137] In the formula:

[0138] K 3 : The heat transfer coefficient of the ground steam injection pipeline;

[0139] t f : The ground environmental temperature;

[0140] t 锅炉 : The steam temperature of the ground steam injection pipeline or the boiler outlet temperature;

[0141] L, l: The total length and the calculated length of the ground steam injection pipeline;

[0142] Based on the corresponding relationship between the heat injection rate and the steam parameters, the corresponding relationship between the heat loss Q of the ground pipeline, the boiler outlet steam parameters, and the wellhead steam parameters is obtained, which satisfies the calculation formula (17): l

[0143]

[0144] Judge whether the pipeline heat loss is lower than the designed value. If it is not lower than the designed value, it means that the heat loss is large and the boiler outlet parameters are low, and the process enters step 104. If it is lower than the designed value, the process enters step 107.

[0145]

[0145] In step 107, when the steam injection volume reaches the designed requirement, the steam injection is stopped. The designed steam injection volume is the basis for periodic steam injection shutdown. At this time, the temperature and energy management from the boiler to the bottom of the well for one cycle of steam injection process is completed. Enter the temperature and energy management subsystem in the production stage of subsystem 2.

[0146] In step 201, the wellhead produced liquid temperature and flow rate monitoring unit is used to collect the wellhead produced liquid temperature. The process enters step 202.

[0147] In step 202, the bottom hole produced liquid temperature processing unit deduces the bottom hole produced liquid temperature t 0 backwards from the collected wellhead produced liquid temperature t w , tw Calculated from the calculation formula (18), the bottom-hole produced fluid temperature t w Also reflects the reservoir temperature in the near-wellbore area at different production times.

[0148]

[0149] In the formula:

[0150] t 0 : The temperature of the produced fluid at the wellhead of the oil well, obtained by testing;

[0151] t w : The bottom-hole produced fluid temperature of the oil well, approximately equal to the reservoir temperature in the near-wellbore area;

[0152] K 1 : The heat transfer coefficient of the production well.

[0153] Judge whether it satisfies tw≥T 流动 . The bottom-hole produced fluid temperature processing unit transmits the data to the reservoir and produced fluid temperature command transceiver control unit. If tw≥T is not satisfied 流动 , the reservoir and produced fluid temperature command transceiver control unit sends a shutdown and cycle change command to the production control system, and the production control system implements a shutdown operation and waits to enter the injection and production cycle of the next period. If tw≥T is satisfied 流动 , the continuous production of the reservoir can be maintained. The process enters step 203.

[0154] In step 203, use the wellbore produced fluid temperature monitoring unit to collect the wellbore temperature along the way and transmit the data to the reservoir and produced fluid temperature command transceiver control unit. The reservoir and produced fluid temperature command transceiver control unit judges whether it satisfies tz≥T at any monitored wellbore position 流动 . If satisfied, normal production. If not satisfied, the process enters step 204.

[0155] In step 204, send a command to the production control system through the reservoir and produced fluid temperature command transceiver control unit. The production control system issues a command to the wellbore heating equipment to start the wellbore electric heating viscosity reduction process. The wellbore electric heating system adjusts the wellbore electric heating power N infinitely according to the heating depth z H and the real-time monitored produced fluid data (produced fluid, water cut, wellhead temperature are the monitored data), 1 N 1 The adjustment method of N is:

[0156] Corresponding to the depth z H t H ≤T 流动 For the well section from 0 to z H , wellbore heating and viscosity reduction measures need to be implemented. The produced fluid temperature t after electric heating zCalculated from the calculation formula (19):

[0157]

[0158] In the formula:

[0159] t z : The produced fluid temperature at the corresponding depth z, °C;

[0160] t 0 : The produced fluid temperature measured at the wellhead, °C;

[0161] t H : The produced fluid temperature at the heating point, °C;

[0162] z H : The depth of the heating point, m;

[0163] W: The water equivalent of the produced fluid, W / °C;

[0164] m: The geothermal gradient, °C / m;

[0165] K 1 : The heat transfer coefficient of the production well, W / (m·°C);

[0166] N 1 : The wellbore heating power, W;

[0167] The heating length z H The corresponding minimum heating power N 1 Determined by the calculation formula (20):

[0168]

[0169] The wellbore electric heating system adjusts the wellbore electric heating power N steplessly according to the heating depth and the real-time monitored produced fluid data 1 , ensuring that the produced fluid temperature t z > T 流动 in the whole wellbore length, and realizing the smooth lifting of the fluid in the wellbore from the bottom to the wellhead. The process enters step 205.

[0170] In step 205, the produced fluid temperature monitoring and analysis unit of the oil pipeline is used to collect the temperature of the oil pipeline along the ground and transmit the data to the reservoir and produced fluid temperature command transceiver control unit. The reservoir and produced fluid temperature command transceiver control unit judges whether t lH ≥T 流动 is satisfied at any monitored pipeline position. If it is satisfied, normal production is carried out. If not, the process enters step 206.

[0171] In step 206, an instruction is sent to the production control system through the reservoir and produced fluid temperature instruction transceiver control unit. The production control system issues an instruction to the oil pipeline heating equipment to start the electro-heating viscosity reduction process for the ground oil pipeline. The electro-heating system for the ground oil pipeline adjusts the electro-heating power N of the oil pipeline steplessly according to the heating length and the real-time monitored produced fluid data. 2 , N 2 The regulation method of

[0172] During the pipeline transportation, when l = l H , the produced fluid temperature t is detected Lh ≤T 流动 , it is necessary to implement electro-heating viscosity reduction for the l H section of the oil pipeline. The corresponding minimum heating power N H corresponding to the heating length l 2 is determined by the calculation formula (21):

[0173]

[0174] In the formula:

[0175] N 2 : Heating power of the ground oil pipeline, W;

[0176] K 4 : Heat transfer coefficient of the ground oil pipeline, W / (m·°C);

[0177] t lH : Produced fluid temperature corresponding to the length l H point, m;

[0178] t f : Ground environmental temperature, taking the average temperature of the corresponding season, °C;

[0179] l: Total length of the ground oil pipeline, m;

[0180] l H : Heating length, m.

[0181] The electro-heating system for the ground oil pipeline adjusts the electro-heating power N of the wellbore steplessly according to the heating length l H and the real-time monitored produced fluid data to ensure that the produced fluid temperature t 2 at the entire pipeline length is lH >T 流动 , and the produced fluid is smoothly transported from the wellhead to the gathering station through the pipeline. The process enters step 207.

[0182] In step 207, when the wellbore and the ground oil pipeline satisfy tz / t at any monitored position lH ≥T 流动During production, the smooth transportation of the produced fluid from the reservoir to the wellbore and then to the central processing facility is achieved in a cyclic production process. At this time, the temperature and energy management from the reservoir to the wellbore and then to the central processing facility in the cyclic production process is completed.

[0183] Through steps 201 - 207, the smooth transportation of the produced fluid from the reservoir - wellbore - surface pipeline - central processing facility in a cyclic production process is completed. Once the reservoir temperature is lower than T 流动 , shut - in the well and switch to the next cycle in a timely manner to ensure the efficient development of shallow extra - heavy oil.

[0184] Through the systematic management of temperature and energy in the entire injection, production, and transportation system of shallow extra - heavy oil reservoirs, the efficient operation of injection and production is realized. By applying the bucket law, the short - board effect in the wellbore lifting or surface pipeline transportation links during the production process is avoided, and the efficient operation of such reservoirs is achieved.

[0185] The following are several specific embodiments of applying the present invention

[0186] Embodiment 1

[0187] In a specific Embodiment 1 of applying the present invention, the energy - temperature management method for the entire injection - production process of shallow extra - heavy oil of the present invention includes:

[0188] 1. First, determine the flowing temperature T of the crude oil in the reservoir according to statistical formula (1) 流动 . For safety, it can be increased by 5%, that is, the designed flowing temperature T 流动 = 1.05×T 流动 . The higher the viscosity of the crude oil, the higher the corresponding flowing temperature T 流动 .

[0189] 2. The effective oil - supply radius r during the steam stimulation process of heavy oil is usually ≤ 25m. If the radius is designed too large, the steam injection parameters are too large, the steam injection time is too long, and the heat loss of the reservoir is large, which affects the economy. The higher the viscosity of the crude oil, the higher the corresponding flowing temperature, and the smaller the effective oil - supply radius. Generally, for extra - heavy oil with a viscosity greater than 100000 mPa·s, the designed effective oil - supply radius is about 15m; for super - heavy oil with a viscosity greater than 50000 mPa·s, the designed effective oil - supply radius is about 20m; for thick oil with a viscosity greater than 30000 mPa·s, the designed effective oil - supply radius is about 23m; for ordinary thick oil with a viscosity less than 30000 mPa·s, the designed effective oil - supply radius is about 25m. Design the effective oil - supply radius r according to the viscosity of the crude oil in the block.

[0190] 3. According to the effective oil - supply radius r and the flowing temperature T 流动 , design the lowest bottom - hole steam injection temperature t sw according to calculation formula (3), and at the same time design the lowest bottom - hole heat injection rate H W according to calculation formula (5).

[0191] 4. According to the steam injection wellbore structure, design the lowest wellhead heat injection rate H according to the calculation formula (11). 0 .

[0192] 5. According to the surface steam transmission pipeline structure, design the lowest boiler outlet heat injection rate H by the calculation formula (16). 锅炉 .

[0193] 6. Each link of steam injection effectively heats the reservoir under the condition of meeting the lowest heat injection rate.

[0194] 7. During the production process, the liquid production temperature t at the wellhead is monitored in real time. 0 , when t 0＜ T 流动 , wellbore viscosity reduction measures should be implemented.

[0195] 8. According to the depth z where the monitored wellbore liquid production temperature is lower than T 流动 , determine the minimum wellbore heating power N according to the calculation formula (20) H , ensuring that the liquid production temperature at any point within the heated well section is greater than T 1 . 流动 .

[0196] 9. According to the length l where the detected surface steam transmission pipeline liquid production temperature is lower than T 流动 , determine the minimum surface pipeline transportation heating power N according to the calculation formula (21) H , ensuring that the liquid production temperature at any point within the surface pipeline transportation pipeline from the heating point to the joint station is greater than T 2 , ensuring that the liquid production reaches the joint station smoothly. 流动 .

[0197] Example 2

[0198] For an extra - super heavy oil well, the main parameters are as follows:

[0199] The ground crude oil viscosity is 350000 mPa·s, the oil layer depth is 488 m, the static pressure of the oil layer is 4.78 MPa, the effective thickness of the oil layer is 12 m. High - vacuum heat - insulated tubing of 76 * 114.3 mm is used for steam injection and production. The surface steam transmission pipeline is 69 * 89 mm, the thickness of the thermal insulation layer is 35 mm, the length of the steam transmission pipeline is 120 m, the oil transportation pipeline is 76 * 89 mm tubing, and the length is 500 m. The heat transfer coefficient K of the wellbore production system 1 = 0.67 w / (m·℃), the heat transfer coefficient K of the wellbore steam injection system 2 = 0.37 w / (m·℃), the heat transfer coefficient K of the surface steam transmission pipeline 3 = 0.27 w / (m·℃), the heat transfer coefficient K of the surface oil transportation pipeline 4 = 1.17 w / (m·℃), and the ground temperature gradient m = 0.022℃ / m.

[0200] (1) Calculate the flowing temperature of crude oil

[0201] Calculate the flowing temperature of crude oil from the calculation formula (1) of viscosity and flowing temperature:

[0202] T 流动 = 9.7266×ln(0.97×350000) - 35.093

[0203] T 流动 = 85.46°C, design T 流动 = 1.05×85.46 = 93.21°C

[0204] (2) Design the effective oil supply radius

[0205] r = 17m, and at the same time, determine the lowest bottom-hole steam injection temperature t from the calculation formula (3) sw≥ 310°C.

[0206] (3) Temperature and energy management during the steam injection process

[0207] ① Design the lowest bottom-hole heat injection rate

[0208] From the calculation formula (5)

[0209]

[0210] Calculate to obtain:

[0211] H W ≥5969659W

[0212] Speculate the lowest bottom-hole steam parameters from the calculation formula (6):

[0213] H w = G(i w + r w x w - i z )

[0214] Table 1 The lowest bottom-hole steam parameters

[0215]

[0216] Parameters such as the steam injection rate, steam injection time, and bottom-hole steam dryness higher than the values in the table can meet the requirements of the lowest bottom-hole heat injection rate.

[0217] ② Predict the lowest wellhead steam parameters

[0218] From the calculation formula (11), calculate to reach H W ≥5969659W, and the corresponding lowest wellhead steam parameter is H 0≥6783172 W.

[0219]

[0220] Table 2 Minimum Wellhead Steam Parameters

[0221]

[0222] With the injection rate unchanged, on the premise of ensuring the bottom-hole injection pressure, appropriately reduce the injection pressure to reduce the heat dissipation loss term. Increasing the wellhead steam dryness can increase the heat injection rate H at the bottom hole. W .

[0223] ③ Predict the minimum parameters at the boiler outlet

[0224] From calculation formula (15), predict the minimum steam parameters H at the boiler outlet. 锅炉 ≥6802683 W

[0225]

[0226] Table 3 Minimum Steam Parameters at the Boiler Outlet

[0227]

[0228] With the injection rate unchanged, on the premise of ensuring the wellhead injection pressure and heat injection rate H 0 , increase the wellhead steam dryness, strengthen the heat insulation performance of the pipeline, and reduce K 3 , and reduce the heat dissipation loss term. It can increase the heat injection rate H at the wellhead. 0 .

[0229] On the premise of ensuring ① - ③, the mobilization of heavy oil within the effective heating radius r can be achieved.

[0230] (4) Temperature Management during the Production Process

[0231] ① Initial production stage: For extra - heavy oil, usually within about 20 days after the well is opened, the reservoir temperature is high, the liquid production is large (30 t / d), the water cut is high (more than 85%), the wellhead temperature is high, and the measured wellhead temperature is greater than the flowing temperature t 0 ≥T 流动 . During the wellbore lifting process, there is no lifting problem, and the liquid production and heavy oil at the bottom hole can reach the wellhead smoothly. During the surface pipeline transportation process, the back pressure is normal, and the temperature reaching the gathering station is higher than the flowing temperature, and the pipeline transportation is normal. In this process, it is not necessary to calculate the temperature, and only the measured wellhead temperature, the pumping unit load, and the wellhead back pressure need to be judged.

[0232] ② Wellbore temperature management in the middle and late production stage: The reservoir temperature remains at a relatively high level, the liquid production rate decreases, the water cut decreases, and the temperature of the produced liquid reaching the wellhead gradually drops below the flowing temperature. The load of the pumping unit increases by 15%, and measures for reducing viscosity by electric heating need to be applied. First, based on the measured wellhead temperature t 0 Back-calculate the temperature t of the produced liquid at any point from the wellhead to the bottom of the well z , from the calculation formula (19)

[0233]

[0234] For example: Given a daily liquid production of 35 t / d, a water cut of 75%, and the measured wellhead temperature t 0 = 65.22 °C, back-calculate according to formula (19):

[0235] t 0 = 65.22 °C

[0236] t 417 = 93.32 °C

[0237] t 450 = 98.01 °C

[0238] From the designed flowing temperature T 流动 = 93.21 °C, viscosity reduction measures need to be implemented in the well section above 417 m. Taking electric heating as an example, the designed wellhead temperature after heating is T 流动 = 93.21 °C, the heating depth is 417 m, from the calculation formula of wellbore heating power (20):

[0239]

[0240] Predict the corresponding total heating power as N 1 = 39 KW, the heating power per meter is 93.52 W / m. After heating, the wellhead temperature t 0 = 96 °C.

[0241] The heating power is a dynamic value and needs to be adjusted in real time according to the changes in the produced liquid temperature at the wellhead and the load of the pumping unit.

[0242] ③ Temperature management of surface oil pipelines

[0243] The surface oil transportation process is a heat dissipation process. During the pipeline transportation, the temperature of the produced liquid will inevitably gradually decrease. The temperature of the produced liquid at the wellhead is the initial temperature of the surface oil pipeline. From the calculation formula

[0244]

[0245] For a daily liquid production of 35 t / d, a water cut of 75%, and the measured wellhead temperature t 0 = 96 °C, and a pipeline length of 500 m, the calculated temperature is:[[]]

[0246] 0m:t l0 = 96 °C

[0247] 175m:t l75 = 93.22 °C

[0248] 500m:t 500 = 74.01 °C

[0249] After 175 m of the oil pipeline, the produced fluid temperature is lower than the flowing temperature T 流动 , resulting in an increase in the wellhead backpressure. Electrical heating tracing for viscosity reduction needs to be implemented. From the calculation formula (22):

[0250]

[0251] Determine the electrical heating for 325 m of the oil pipeline and the total heating power N 2 = 15.3 KW, the heating power per meter is 47.67 W / m. After heating, 500m:t 500 = 93.01 °C

[0252] Example 3

[0253] In the specific Example 3 of applying the present invention, the ground crude oil viscosity is 1050000 mPa·s, the oil layer depth is 268 m, the original formation temperature is 21.3 °C, the effective thickness of the oil layer is 7.5 m, the injection and production pipelines in the wellbore use 76*114.3 mm high-vacuum heat-insulating oil pipes, the ground steam pipeline is 69*89 mm, the thickness of the thermal insulation layer is 45 mm, the length of the steam pipeline is 55 m, the oil pipeline is 76*89 mm oil pipe, and the length is 200 m. The heat transfer coefficient K of the wellbore 1 = 0.39 w / (m·°C), the heat transfer coefficient K of the wellbore steam injection system 2 = 0.37 w / (m·°C), the heat transfer coefficient K of the ground steam pipeline 3 = 0.22 w / (m·°C), the heat transfer coefficient K of the ground oil pipeline 4 = 0.47 w / (m·°C), the geothermal gradient m = 0.022 °C / m, and the atmospheric temperature is 19 °C

[0254] (1) Calculate the flowing temperature of the crude oil

[0255] Calculate the flowing temperature of the crude oil from the calculation formula (1) of viscosity and flowing temperature:

[0256] T 流动 = 9.7266 × ln(0.97 × 1050000) - 35.093

[0257] T 流动 = 99.49 °C, design T 流动= 1.05 × 99.49 = 104.46 °C

[0258] (2) Design the effective oil supply radius

[0259] r = 15 m. At the same time, the lowest steam injection temperature at the bottom of the well is determined by calculation formula (3) as t sw ≥ 352 °C.

[0260] (3) Temperature and energy management during the steam injection process

[0261] ① Design the lowest heat injection rate at the bottom of the well

[0262] From calculation formula (5)

[0263]

[0264] The calculation shows that:

[0265] H W ≥ 6796678 W

[0266] Speculate the lowest steam parameters at the bottom of the well from calculation formula (6):

[0267] H w = G(i w + r w x w - i z )

[0268] Table 4 The lowest steam parameters at the bottom of the well

[0269]

[0270] Parameters such as the steam injection rate, steam injection time, and steam dryness at the bottom of the well higher than the values in the table can meet the requirements of the lowest heat injection rate at the bottom of the well.

[0271] ② Predict the lowest steam parameters at the wellhead

[0272] From calculation formula (11), calculate to reach H W ≥ 6796678 W, and the corresponding lowest wellhead steam parameter is H 0 ≥ 7760471 W.

[0273]

[0274] Table 5 The lowest wellhead steam parameters

[0275]

[0276] Increase the steam injection rate and reduce the heat dissipation loss Increase the steam dryness at the wellhead, and all can achieve an increase in the heat injection rate H at the bottom of the well W .

[0277] ③Predict the lowest parameters at the boiler outlet

[0278] From the calculation formula:

[0279]

[0280] Predict the lowest steam parameters H at the boiler outlet 锅炉 ≥7774439 W.

[0281] Table 6 Lowest steam parameters at the boiler outlet

[0282]

[0283] Increasing the steam injection rate of the boiler, increasing the steam dryness at the wellhead, strengthening the heat insulation performance of the pipeline, extending the steam injection time, etc. can all increase the heat injection rate H at the wellhead 0 , and finally realize the production of heavy oil within the effective heating radius r.

[0284] (4) Temperature management during the production process

[0285] ①In the initial stage of production: The oil well is shallow, the heat loss along the wellbore is small. About 16 days after opening the well, the daily liquid production ≥ 11 t / d. The reservoir temperature is high and the liquid supply capacity is strong. The wellhead temperature ≥ 110 °C, realizing the smooth lifting of the wellbore. The ground oil transportation distance is short, and the heat insulation effect of the oil transportation pipeline is good. During the ground pipeline transportation process, the back pressure is normal, and the temperature reaching the gathering station ≥ 105 °C, and the pipeline transportation is normal. There is no need to heat the produced liquid temperature of the wellbore and the pipeline.

[0286] ②In the middle and late stages of production: The reservoir temperature and the liquid production volume gradually decrease. The liquid volume is 10.7 t / d and the wellhead temperature is 95 °C, which is lower than the flowing temperature of 104.46 °C. The load of the pumping unit increases significantly, and the reservoir temperature is inversely deduced to be about 119 °C. The reservoir temperature > T 流动 , and there is the potential for continued production. It is necessary to implement downhole electrical heating to achieve efficient lifting. First, based on the measured wellhead temperature t 0 Inversely deduce the produced liquid temperature t at any point from the wellhead to the bottom of the well z , from the calculation formula (19)

[0287]

[0288] For example: Given a daily liquid production of 10.7 t / d, a water cut of 75%, and the measured wellhead temperature t 0 = 95 °C, inversely deduce:

[0289] t 0 = 95.02 °C

[0290] t 150 = 99.42 °C

[0291] t 268 = 119 °C

[0292] From the designed flow temperature T 流动 = 99.49 °C, for the well section above 150 m, heating design needs to be implemented. The wellhead temperature after heating is T 流动 = 106 °C, the heating depth is 150 m. From the calculation formula (20) of the heating power of the wellbore:

[0293]

[0294] Predict the corresponding total heating power as N 1 = 17 KW, the heating power per meter is 113 W / m, and the wellhead temperature t after heating 0 = 106 °C.

[0295] ③ Temperature management of the surface oil pipeline

[0296] For a daily liquid volume of 10.7 t / d, a water content of 55%, and a wellhead temperature t 0 = 106 °C, there is a problem of increasing back pressure in the surface oil pipeline. From the calculation formula

[0297]

[0298] The temperature distribution along the pipeline is tested and analyzed as follows:

[0299] 0 m: t l0 = 106 °C

[0300] 105 m: t 105 = 99.22 °C

[0301] 200 m: t 500 = 94.01 °C

[0302] After 105 m of the oil pipeline, the produced liquid temperature is lower than the flow temperature T 流动 , and electric heating tracing for viscosity reduction needs to be implemented. From the calculation formula (21):

[0303]

[0304] Determine that the oil pipeline is electrically heated for 95 m, and the total heating power N 2 = 9.3 KW, and the heating power per meter is 97.9 W / m. After heating, at 200 m: t 200 = 105.2 °C.

[0305] Finally, it should be noted that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

[0306] Except for the technical features described in the specification, the rest are well-known technologies to those skilled in the art.

Claims

1. Energy and temperature management system for the whole process of shallow extra - heavy oil injection and production, Characterized in that, This energy and temperature management system for the whole process of shallow extra - heavy oil injection and production includes an energy and temperature management system for the steam injection process, and an energy and temperature management system for the reservoir and produced fluid during the production process. The energy and temperature management system for the steam injection process designs the minimum heating temperature of the reservoir and the energy demand corresponding to the cyclic steam injection development radius, designs the minimum steam parameters at the bottom of the well, monitors the steam parameters at the wellhead and the inlet of the surface pipeline in real time, and controls the outlet parameters of the boiler to meet the minimum steam injection requirements of the reservoir; The energy and temperature management system for the reservoir and produced fluid during the production process monitors the wellhead temperature and flow rate, analyzes to obtain the reservoir temperature at the bottom of the well, determines whether to continue production or switch cycles based on the reservoir temperature at the bottom of the well, and ensures that the temperature of the produced fluid during the production process is greater than the flowing temperature to achieve the smooth transportation of the produced fluid from the reservoir to the wellbore and then to the gathering station.

2. The energy and temperature management system for the whole process of shallow extra - heavy oil injection and production according to claim 1, Characterized in that, The energy and temperature management system for the steam injection process includes an oil reservoir flow temperature processing unit and an oil reservoir steam parameter analysis unit. The oil reservoir flow temperature processing unit is connected to the oil reservoir steam parameter analysis unit, collects the ground viscosity data μ of the crude oil in the development well, and designs the minimum flow temperature T of the oil reservoir based on the ground viscosity data μ 流动 , and the oil reservoir steam parameter analysis unit collects the initial temperature t of the oil reservoir zw , sets the effective heating radius r, and designs the minimum bottom-hole steam temperature t 流动 and the minimum heat injection rate H sw based on the minimum flow temperature T of the oil reservoir W .

3. The energy and temperature management system for the whole process of shallow extra - heavy oil injection and production according to claim 2, Characterized in that, The energy and temperature management system for the steam injection process further includes a bottom-hole steam parameter monitoring and analysis unit, which is connected to the reservoir steam parameter analysis unit. Based on the lowest steam temperature t sw and the lowest heat injection rate H W , the bottom-hole steam parameters are designed, including the steam injection rate G, the steam pressure P sw , and the steam quality x w .

4. The energy and temperature management system for the whole process of shallow extra - heavy oil injection and production according to claim 3, Characterized in that, This energy and temperature management system for the steam injection process further includes a wellhead steam parameter monitoring and analysis unit and a surface steam pipeline inlet steam parameter monitoring and analysis unit. The wellhead steam parameter monitoring and analysis unit and the surface steam pipeline inlet steam parameter monitoring and analysis unit monitor the steam parameters at the wellhead and the inlet of the surface pipeline in real time. The wellhead steam parameter monitoring and analysis unit predicts the minimum wellhead steam parameters based on the designed steam parameters at the bottom of the well and the heat loss in the wellbore; The surface steam pipeline inlet steam parameter monitoring and analysis unit predicts the minimum inlet steam parameters of the surface pipeline based on the heat loss of the surface pipeline.

5. The energy and temperature management system for the whole process of shallow extra - heavy oil injection and production according to claim 4, Characterized in that, This energy and temperature management system for the steam injection process further includes a steam parameter command transceiver unit and a boiler outlet parameter control system. The steam parameter command transceiver unit is connected to the bottom - hole steam parameter monitoring and analysis unit, the wellhead steam parameter monitoring and analysis unit, and the surface steam pipeline inlet steam parameter monitoring and analysis unit. When any one of the bottom - hole steam parameters, wellhead steam parameters, and pipeline inlet steam parameters is lower than the minimum designed parameters, the steam parameter command transceiver unit receives and sends commands to the boiler outlet parameter control system to control the outlet parameters of the boiler, meet the minimum steam injection requirements of the reservoir, and achieve efficient steam injection in the reservoir.

6. The energy and temperature management system for the whole process of shallow extra - heavy oil injection and production according to claim 5, Characterized in that, This energy and temperature management system for the steam injection process further includes a steam injection terminal processing unit. The steam parameter command transceiver unit is connected to the boiler outlet parameter control system and the steam injection terminal processing unit. The steam injection terminal processing unit receives the total steam injection volume information and stops steam injection and switches cycles when the designed steam injection time is reached.

7. The energy and temperature management system for the whole process of shallow extra - heavy oil injection and production according to claim 2, It is characterized in that the reservoir and produced fluid energy and temperature management system for this production process includes a wellhead produced fluid temperature and flow rate monitoring unit, a bottomhole produced fluid temperature processing unit, a reservoir and produced fluid temperature command transceiver control unit, and a production control system. The wellhead produced fluid temperature and flow rate monitoring and processing unit monitors the wellhead temperature and flow rate, provides the data to the bottomhole produced fluid temperature processing unit. The bottomhole produced fluid temperature processing unit analyzes to obtain the bottomhole reservoir temperature, transmits the bottomhole reservoir temperature to the reservoir and produced fluid temperature command transceiver control unit, and is transmitted by the reservoir and produced fluid temperature command transceiver control unit to the production control system. The production control system determines whether to continue production or switch cycles based on the reservoir temperature at the bottom of the well.

8. The energy and temperature management system for the whole process of injection-production of shallow extra-heavy oil according to claim 7, It is characterized in that The reservoir and produced fluid energy and temperature management system for this production process further includes a wellbore produced fluid temperature monitoring unit, an oil pipeline produced fluid temperature monitoring and analysis unit, a wellbore electric heating control unit, and a surface pipeline electric heating control unit. The temperatures at various points in the wellbore and surface oil pipeline obtained by monitoring and analyzing by the wellbore produced fluid temperature monitoring unit and the oil pipeline produced fluid temperature monitoring and analysis unit are transmitted to the reservoir and produced fluid temperature command transceiver and control unit. When the wellbore temperature is lower than the flowing temperature T 流动 , the reservoir and produced fluid temperature command transceiver and control unit sends a command to the production control system to start the wellbore electric heating control unit to start heating up the wellbore; when the surface oil pipeline temperature is lower than the flowing temperature T 流动 , the reservoir and produced fluid temperature command transceiver and control unit sends a command to the production control system to start the surface pipeline electric heating control unit to start heating up the pipeline.

9. The energy and temperature management system for the whole process of injection-production of shallow extra-heavy oil according to claim 8, It is characterized in that The reservoir and liquid production energy and temperature management system for this production process further includes a combined station and a shutdown and cycle conversion instruction transceiver unit. The wellbore electric heating control unit determines the wellbore heating depth Z H and designs the wellbore heating power N 1 to implement wellbore heating for temperature rise. The surface pipeline electric heating control unit determines the pipeline heating depth l H and designs the wellbore heating power N 2 to implement pipeline heating for temperature rise. The combined station processes the produced liquid. When the bottom-hole produced liquid temperature is lower than the flowing temperature T 流动 , the shutdown and cycle conversion instruction transceiver unit sends a shutdown instruction to the reservoir flowing temperature processing unit to enter the steam injection link of the next cycle.

10. The energy and temperature management method for the steam injection process, It is characterized in that the energy and temperature management method for the steam injection process adopts the energy and temperature management system for the whole process of injection-production of shallow extra-heavy oil described in claim 1, including: Step 1: Use the reservoir flow temperature treatment unit to collect the crude oil viscosity, establish the flow correspondence relationship between the heavy oil viscosity and temperature, and clarify the flow temperature T 流动 ; Step 2: Using the reservoir steam parameter analysis unit, collect the reservoir temperature, design the heating radius, and predict the minimum bottom-hole steam temperature t sw and the heat injection rate Hw; Step 3: Use the bottom-hole steam parameter monitoring and analysis unit to collect the bottom-hole steam parameters. The bottom-hole steam parameter monitoring and analysis unit determines whether the bottom-hole heat injection rate Hw and the steam temperature t sw meet the heating radius requirement; Step 4: Send commands to the boiler outlet parameter control system through the steam parameter command transceiver unit to adjust the boiler parameters; Step 5: Use the wellhead steam parameter monitoring and analysis unit to collect the wellhead steam parameters and determine whether the minimum heat injection rate at the bottom of the well meets the design requirements; Step 6: Use the steam parameter monitoring and analysis unit at the inlet of the surface steam transmission pipeline to collect the steam parameters at the pipeline inlet and determine whether the pipeline heat loss is lower than the design value; Step 7: The steam injection terminal processing unit stops steam injection when the steam injection parameters for the heating radius design are met, completes the temperature and energy management from the boiler to the bottom of the well, and transfers to the production operation management.

11. The energy and temperature management system for the whole process of injection-production of shallow extra-heavy oil according to claim 10, It is characterized in that In step 1, the oil reservoir flow temperature treatment unit collects the ground viscosity data μ of the crude oil from the development well o , and the calculation formula (1) provides the crude oil viscosity μ of heavy oil with different viscosities o and the corresponding relationship with the flow temperature T 流动 , and T 流动 simultaneously serves as the minimum heating temperature of the reservoir: T 流动 = 9.7266 × ln(0.97μ o ) - 35.093 (1).

12. The energy and temperature management system for the whole process of injection-production of shallow extra-heavy oil according to claim 10, It is characterized in that In step 2, the initial temperature t of the reservoir is collected. zw The steam parameter analysis unit of the reservoir designs an effective heating radius r of the reservoir for a huff and puff cycle, and requires that the reservoir temperature Tr within the effective heating radius r ≥ T. 流动 Based on r and T. 流动 The bottom-hole heat injection rate and the steam temperature entering the reservoir are determined.

13. The energy and temperature management system for the whole process of injection-production of shallow extra-heavy oil according to claim 10, It is characterized in that In step 3, using the reservoir steam parameter analysis unit, the demand for the minimum steam parameters at the well bottom, including the steam injection rate G, the steam temperature t 流动 and the steam quality x sw w is established. When the heat injection rate and the steam temperature at the well bottom meet the heating radius requirement, the current steam injection status is maintained. When the heating radius requirement is not met, step 4 is entered.​ 14. The energy and temperature management system for the whole process of injection-production of shallow extra-heavy oil according to claim 10, It is characterized in that In step 4, send commands to the boiler outlet parameter control system through the steam parameter command transceiver unit to adjust the boiler outlet parameters, and increase one or more steam parameters at the boiler outlet to achieve the target value.

15. The energy and temperature management system for the whole process of injection-production of shallow extra-heavy oil according to claim 10, It is characterized in that In step 5, use the wellhead steam parameter monitoring and analysis unit to collect the wellhead steam parameters, and inversely deduce the minimum wellhead steam parameters based on the minimum heat injection rate at the bottom of the well and the bottomhole steam temperature; the wellhead steam parameter monitoring and analysis unit determines whether the wellhead steam parameters meet the design requirements; if not, it indicates that the wellhead steam parameters do not meet the standards, and the process enters step 4; if they meet, the process enters step 6.

16. The energy and temperature management system for the whole process of injection-production of shallow extra-heavy oil according to claim 10, It is characterized in that In step 6, a steam parameter monitoring and analysis unit at the ground steam pipeline inlet is used to collect the steam parameters at the pipeline inlet, i.e., the steam parameters at the boiler outlet, and based on the wellhead steam injection parameters and the insulation condition of the ground pipeline, the minimum steam parameter H at the inlet of the injection pipeline, i.e., the boiler outlet, is inversely deduced and designed; 锅炉 and the minimum heat loss of the pipeline; the steam parameter monitoring and analysis unit at the steam pipeline inlet judges whether the heat loss of the pipeline is lower than the designed value; If it is not lower than the design value, it indicates that the heat loss is large and the boiler outlet parameters are low, and the process enters step 4; If it is lower than the design value, the process enters step 7.

17. The energy temperature management system for the whole process of shallow extra - heavy oil injection and production according to claim 10, It is characterized in that In step 7, when the steam injection terminal processing unit determines that the steam injection volume reaches the design requirement, the steam injection is stopped. The designed steam injection volume is the basis for periodic steam injection suspension. At this time, the temperature and energy management from the boiler to the bottom of the well for one cycle of steam injection process is completed; Enter the temperature and energy management subsystem in the production stage.

18. The temperature and energy management method in the production stage, It is characterized in that The temperature and energy management method in the production stage adopts the energy temperature management system for the whole process of shallow extra - heavy oil injection and production described in claim 1, including: Step 21, using the wellhead liquid production temperature and flow monitoring unit to collect the wellhead temperature; Step 22, back-calculate the bottom-hole produced fluid temperature t w , and determine t w ≥T 流动 ; Step 23: Use the wellbore fluid production temperature monitoring unit to collect the wellbore temperature along the way and judge whether the temperature t at any monitoring point z ≥T 流动 ; Step 24, sending an instruction to the production control system through the reservoir and liquid production temperature instruction transceiver control unit to start the down - viscosity process of wellbore electric heating; Step 25: Use the liquid production temperature monitoring and analysis unit of the oil pipeline to collect the temperature of the pipeline along the ground and determine whether the temperature t at any monitoring point lh ≥T 流动 ; Step 26, sending an instruction to the production control system through the reservoir and liquid production temperature instruction transceiver control unit to start the down - viscosity process of pipeline electric heating; Step 27, when t at any monitoring point of the wellbore and pipeline z / t lh ≥T 流动 production is carried out to achieve the smooth transportation of the produced fluid from the reservoir to the wellbore and then to the central processing facility.

19. The energy temperature management system for the whole process of shallow extra - heavy oil injection and production according to claim 18, It is characterized in that In step 22, the bottom-hole produced fluid temperature processing unit back-calculates the bottom-hole produced fluid temperature t 0 from the collected wellhead produced fluid temperature t w ,t w obtained by calculating with the calculation formula (18). The bottom-hole produced fluid temperature t w simultaneously reflects the reservoir temperature in the near-wellbore area at different production times; Where: t 0 : The temperature of the fluid produced at the wellhead of the oil well, obtained through testing; t w : The temperature of the fluid produced at the bottom of the oil well, which is approximately equal to the reservoir temperature in the near-wellbore zone; K 1 : Heat transfer coefficient of production well; m: Low - temperature gradient; W: Water equivalent of the produced liquid; Z: Depth.

20. The energy temperature management system for the whole process of shallow extra - heavy oil injection and production according to claim 19, It is characterized in that In step 22, it is judged whether t w ≥T 流动 ; the bottom-hole produced fluid temperature processing unit transmits the data to the reservoir and produced fluid temperature command transceiver control unit. If t w ≥T 流动 is not satisfied, the reservoir and produced fluid temperature command transceiver control unit sends a production suspension and cycle conversion command to the production control system, and the production control system implements the production suspension operation and waits to enter the injection and production cycle of the next cycle; if t w ≥T 流动 is satisfied, the continuous production of the reservoir can be maintained; the process enters step 23.

21. The energy temperature management system for the whole process of shallow extra - heavy oil injection and production according to claim 18, It is characterized in that In step 23, the wellbore fluid production temperature monitoring unit is used to collect the temperature of the wellbore along the way and transmit the data to the reservoir and fluid production temperature command transceiver control unit. The reservoir and fluid production temperature command transceiver control unit determines whether t z ≥T 流动 is satisfied at any monitored wellbore position; if it is satisfied, normal production is carried out, and if it is not satisfied, the process proceeds to step 24.

22. The energy temperature management system for the whole process of shallow extra - heavy oil injection and production according to claim 18, It is characterized in that In step 24, the reservoir and produced fluid temperature instruction transceiver control unit sends an instruction to the production control system, and the production control system issues an instruction to the wellbore electric heating control unit to start the wellbore electric heating viscosity reduction process; the wellbore electric heating control unit adjusts the wellbore electric heating power N steplessly according to the heating depth z H and the produced fluid data monitored in real time 1 to ensure that the produced fluid temperature t z > T 流动 along the entire wellbore length, so as to realize the smooth lifting of the fluid in the wellbore from the bottom of the well to the wellhead.

23. The energy temperature management system for the whole process of shallow extra - heavy oil injection and production according to claim 18, It is characterized in that In step 25, the oil pipeline produced fluid temperature monitoring and analysis unit is used to collect the temperature of the oil pipeline along the ground, and transmit the data to the reservoir and produced fluid temperature command transceiver and control unit. The reservoir and produced fluid temperature command transceiver and control unit determines whether t lH ≥T 流动 is satisfied at any monitored pipeline position; if it is satisfied, normal production is carried out, and if it is not satisfied, the process proceeds to step 26.

24. The energy temperature management system for the whole process of shallow extra - heavy oil injection and production according to claim 18, It is characterized in that In step 26, the reservoir and produced fluid temperature instruction transceiver control unit sends an instruction to the production control system, and the production control system issues an instruction to the ground pipeline electric heating control unit to start the electric heating viscosity reduction process for the ground oil pipeline; the ground pipeline electric heating control unit steplessly adjusts the electric heating power N of the oil pipeline according to the heating length and the produced fluid data monitored in real time 2 , ensuring that the produced fluid temperature t lH > T 流动 , and realizing the smooth pipeline transportation of the produced fluid from the wellhead to the joint station.

25. The energy temperature management system for the whole process of shallow extra - heavy oil injection and production according to claim 18, It is characterized in that In step 27, when the wellbore liquid production temperature monitoring unit and the oil pipeline liquid production temperature monitoring and analysis unit monitor that any monitored position t z / t lH ≥T 流动 maintain normal production and transportation, and achieve the smooth transportation of the produced liquid from the reservoir to the wellbore and then to the joint station during the cyclic production process. At this time, the temperature and energy management of the cyclic production process from the reservoir to the wellbore and then to the joint station is completed.

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