Oil extraction and water reduction combined multi-source heating system

Abstract

The invention relates to the technical field of oil extraction and water reduction, in particular to an oil extraction and water reduction combined multi-source heating system which comprises an oil storage and water reduction separator, a liquid inlet is formed in one side of the top of the oil storage and water reduction separator, an exhaust port is formed in the middle of the top of the oil storage and water reduction separator, and a water outlet and an oil outlet are formed in one side of the bottom of the oil storage and water reduction separator. The oil storage and water reduction separator is used for receiving produced liquid with high water content in an oil well, removing a water phase and a gas phase through physical separation, outputting an intermediate oil phase with low water content to the heating furnace, and conveying the separated high-temperature water phase to the multi-source heat pump unit for heat recovery. Compared with the prior art, the oil storage and water reduction separator is arranged to be matched with the waste heat recovery multi-source heat exchange unit, most of water phases in produced liquid are rapidly removed, the follow-up treatment burden is relieved, the conveying efficiency is improved, multi-source cooperative energy supply is achieved, dependence on traditional fossil energy is reduced, and the energy utilization efficiency is improved; the environment-friendly property and the sustainability are good.

Description

Technical Field

[0001] The present invention relates to the technical field of oil production water reduction, and particularly to an oil production water reduction combined with a multi-source heating system. Background Art

[0002] During the current oilfield exploitation process, the produced crude oil liquid generally has the characteristics of high water content and deep emulsification degree. Especially in the middle and late exploitation stages, the water content in the produced liquid can be as high as more than 90%. If it is directly transported to the joint station for treatment without preliminary separation, it will not only increase the transportation energy consumption and equipment wear, but also cause the overloading of the treatment system, affecting the overall operation efficiency and stability.

[0003] In the prior art, most oil production systems usually adopt gas-fired heating furnaces or air-source heat pump heating methods for centralized heating and separation, lacking a front-end separation and water reduction mechanism, resulting in a large amount of redundant water phase existing in the whole transportation and treatment links, not only increasing the overall operation cost and reducing production safety; At the same time, traditional heating systems generally rely on natural gas or fuel oil furnaces as heat sources, with a single energy structure, low energy efficiency utilization rate, and without fully integrating renewable energy or waste heat resources, resulting in a large consumption of fossil energy, low heating efficiency, large energy consumption indicators, and being unfavorable for the realization of the goals of green oilfield exploitation and energy conservation and carbon reduction. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to propose an oil production water reduction combined with a multi-source heating system to solve the problems that existing oil production systems generally lack a front-end water reduction and multi-source energy supply mechanism, resulting in redundant water phase transportation, a single energy structure, and increased energy consumption.

[0005] Based on the above purpose, the present invention provides an oil production water reduction combined with a multi-source heating system, including an oil storage and water reduction separator. One side of the top of the oil storage and water reduction separator is provided with a liquid inlet, the middle of the top of the oil storage and water reduction separator is provided with an exhaust port, one side of the bottom of the oil storage and water reduction separator is provided with a water outlet and an oil outlet. The oil storage and water reduction separator is used to receive the produced liquid with high water content in the oil well, remove the water phase and gas phase through physical separation, output the intermediate oil phase with a lower water content to the heating furnace, and the separated high-temperature water phase is transported to a multi-source heat pump unit for heat recovery; A waste heat recovery multi-source heat exchange unit, one side of the waste heat recovery multi-source heat exchange unit is connected to the oil production heating furnace; A heating furnace, the heating furnace is connected to the oil outlet of the oil storage and water reduction separator, and a pumping pump body is arranged between the oil outlet and the heating furnace. The heating furnace can use the heat provided by the waste heat recovery multi-source heat exchange unit to increase the temperature of the exported crude oil; Injection well, which is a transformed abandoned oilfield well or a newly drilled well. The injection layer of the injection well for re-injecting sewage is consistent with the oil production layer to prevent pollution of other formation layers. Intermediate heat exchanger, one side of which is connected to the waste heat recovery multi-source heat exchanger unit, and the other side is connected to the water outlet in the oil storage and water reduction separator. A pumping pump body is arranged between the intermediate heat exchanger and the waste heat recovery multi-source heat exchanger unit. The intermediate heat exchanger is used to reduce the temperature of the high-temperature water separated by the water reduction separator and then re-inject it into the injection well. The waste heat recovery multi-source heat exchanger unit uses the heat absorbed from the intermediate heat exchanger to heat the oil production furnace. Control unit, which is interconnected with the temperature sensors, flow meters, and pressure sensors in the waste heat recovery multi-source heat exchanger unit, the heating furnace, and the oil storage and water reduction separator. It is used to dynamically calculate the heat source priority and coordinate the scheduling of each heat source according to the real-time heat source output, oil temperature demand, and injection pressure, and to provide real-time feedback on the heat exchange efficiency and perform closed-loop control in combination with heat load response and energy efficiency evaluation. Among them, the oil storage and water reduction separator includes a cyclone separation component and a gravity sedimentation component.

[0006] Preferably, the waste heat recovery multi-source heat exchanger unit includes: Multi-stage heat exchanger, the first stage recovers the sensible heat of the water phase, and the second stage absorbs solar thermal energy and air source thermal energy; Water temperature control valve, which automatically adjusts the water flow according to the injection well pressure to meet: , where K = 0.5−1.2 is the well pressure correction coefficient, is the real-time data of the injection well pressure sensor.

[0007] Preferably, the first stage of the multi-stage heat exchanger is a double helix countercurrent tube, with the water phase flowing through the inner tube and the oil phase flowing in the opposite direction through the outer tube.

[0008] Preferably, the waste heat recovery multi-source heat exchanger unit includes a combined structure of a plate heat exchanger and a shell-and-tube heat exchanger, and a bypass valve group is provided, which can dynamically switch different heat exchange circuits according to the temperature difference between the inlet and outlet water and the flow demand to optimize the heat recovery efficiency.

[0009] Preferably, the heating furnace includes a heat source priority control strategy: a. Priority is given to using waste heat as the main heat source, and the proportion of waste heat in the total heating energy is not less than 80%; b. When the waste heat supply is insufficient, other heat sources are supplemented in the following order and proportion: ① Solar energy is enabled, and its supplementary amount is 10% of the total required supplementary energy. At the same time, an air source heat pump is enabled, and its supplementary amount reaches 90% of the total required supplementary energy; ②When the solar heat is insufficient, the air source heat pump can make up 100% of the total supplementary energy required.

[0010] Preferably, the control unit includes an intelligent heat source collaborative scheduling module used in conjunction with the heating furnace to execute a dynamic energy distribution strategy.

[0011] Preferably, the control unit has an error closed-loop regulation logic, including the following steps: S1: Collect the oil outlet temperature and the target temperature in real time, and calculate the temperature difference. S2: Determine whether the error tolerance is exceeded. If so, enter the compensation regulation. S3: Select one or more heat sources to participate in the regulation according to the compensation intensity level. S4: Recalculate the energy contribution rate and update the control coefficient every cycle. S5: If the error does not return to zero for more than three cycles, lock the heat source call ratio to the current effective range and send a fault prompt signal at the same time.

[0012] Preferably, the control unit is integrated with a thermal energy abnormal response mechanism. When the output power fluctuation of any heat source exceeds 30%, the reinjection pressure rises beyond the limit, or the heat exchange efficiency is lower than 75%, the following response process is triggered: enable the redundant heat source to temporarily replace the main heat source; record the fault point characteristic code and push the abnormal information to the remote control platform; if the abnormality is not resolved within three consecutive cycles, automatically switch to the full-load operation mode of the air source heat pump and trigger an alarm signal at the same time.

[0013] Preferably, the water inlet of the oil storage and water separation device has an inlet baffle for stabilizing the water flow and preventing the subsequent liquid inlet from disturbing the liquid in the tank. Inside the oil storage and water separation device, automatic separation is carried out by relying on the different densities of water, oil, and gas under the action of gravity. The gas outlet controls the on-off of the gas pipeline through a pressure control valve, and the low-water-content crude oil and the separated high-temperature sewage pipeline control the size of the external output flow through a liquid level control valve.

[0014] Preferably, the reinjection well meets the requirements of low-pressure reinjection and has a filtering device and a degassing device for stabilizing the water flow and reducing the impurities and gas content of the reinjected sewage.

[0015] The beneficial effects of the present invention: This oil production and water reduction combined multi-source heating system, by setting up an oil storage and water separation device in cooperation with a waste heat recovery multi-source heat exchange unit, can achieve efficient oil-water separation of the produced fluid and the recycling of energy. The oil storage and water separation device, through the dual separation mechanisms of cyclone and gravity, quickly removes most of the water phase in the produced fluid, reduces the subsequent treatment burden, and improves the transportation efficiency. The separated hot water enters the waste heat recovery multi-source heat exchange unit, and the heat in the water is recovered through heat exchange technology for heating the exported crude oil. At the same time, the system combines renewable energy sources such as solar energy and air source heat pumps for heating crude oil, realizes multi-source collaborative energy supply, reduces the dependence on traditional fossil energy, improves energy utilization efficiency, and has good environmental protection and sustainability.

[0016] This oil production and water reduction combined multi-source heating system is equipped with a control unit, which can achieve dynamic coordination and compensation control of multiple heat sources. In the case of fluctuations in waste heat supply, energy mutations or system abnormalities, it can quickly respond and automatically adjust the energy distribution ratio. By matching the characteristics of different heat sources, such as the fast response of solar energy and the stable output of heat pumps, it effectively alleviates the intermittency problem of renewable energy. At the same time, an energy stability index is introduced to quantify the system safety margin. In addition, the control unit has an error closed-loop adjustment mechanism, which can dynamically adjust the heat source participation strategy according to the temperature difference to achieve high-precision temperature control. When a heat source is abnormal, redundant heat sources are automatically enabled, effectively improving the stability, safety and energy efficiency level of the system, and significantly reducing the fault response time and the frequency of manual intervention. Brief Description of the Drawings

[0017] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only those of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0018] Figure 1 It is a schematic diagram of the system flow of the present invention; Figure 2 It is a schematic diagram of the error closed-loop adjustment logic flow of the present invention; Figure 3 It is a schematic diagram of the system flow of the present invention; Figure 4 It is a schematic diagram of the heat energy abnormal response mechanism flow of the present invention. Detailed Description of the Embodiments

[0019] To make the purpose, technical solutions and advantages of the present invention clearer and more understandable, the following further elaborates on the present invention in combination with specific embodiments.

[0020] It should be noted that unless otherwise defined, the technical terms or scientific terms used in the present invention shall have the ordinary meanings understood by those of ordinary skill in the field to which the present invention pertains. The "first", "second" and similar terms used in the present invention do not denote any order, quantity or importance, but are only used to distinguish different components. Words such as "including" or "comprising" mean that the elements or objects appearing before this word cover the elements or objects listed after this word and their equivalents, without excluding other elements or objects. Words such as "connected" or "coupled" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Upper", "lower", "left", "right", etc. are only used to represent relative position relationships. When the absolute position of the object being described changes, the relative position relationship may also change accordingly.

[0021] As Figures 1 to 4 shown, the oil production and water reduction combined multi-source heating system includes an oil storage and water reduction separator. One side of the top of the oil storage and water reduction separator is provided with a liquid inlet. The middle of the top of the oil storage and water reduction separator is provided with an exhaust port. One side of the bottom of the oil storage and water reduction separator is provided with a water outlet and an oil outlet. The oil storage and water reduction separator is used to receive the produced liquid with a high water content in the oil well, remove the water phase and gas phase through physical separation, and output the intermediate oil phase with a lower water content to the heating furnace. The separated high-temperature water phase is transported to a multi-source heat pump unit for heat recovery; a waste heat recovery multi-source heat exchanger unit, with one side of the waste heat recovery multi-source heat exchanger unit connected to the oil production heating furnace; a heating furnace, with the heating furnace connected to the oil outlet of the oil storage and water reduction separator, and a pumping pump body is arranged between the oil outlet and the heating furnace. The heating furnace can use the heat provided by the waste heat recovery multi-source heat exchanger unit to increase the temperature of the exported crude oil; an injection well, with the injection well being a reformed abandoned well in the oilfield or a newly drilled well. The layer where the injection well injects sewage is consistent with the oil production layer to prevent pollution of other layer formations; an intermediate heat exchanger, with one side of the intermediate heat exchanger connected to the waste heat recovery multi-source heat exchanger unit and the other side connected to the water outlet in the oil storage and water reduction separator. A pumping pump body is arranged between the intermediate heat exchanger and the waste heat recovery multi-source heat exchanger unit. The intermediate heat exchanger is used to reduce the temperature of the high-temperature water separated by the water reduction separator and then inject it into the injection well. The waste heat recovery multi-source heat exchanger unit uses the heat absorbed from the intermediate heat exchanger to heat the oil production heating furnace; a control unit, with the control unit interconnected with the temperature sensors, flow meters, and pressure sensors in the waste heat recovery multi-source heat exchanger unit, the heating furnace, and the oil storage and water reduction separator. It is used to dynamically calculate the heat source priority and coordinate the scheduling of each heat source according to the real-time heat source output, oil temperature demand, and injection pressure, and to provide real-time feedback on the heat exchange efficiency and perform closed-loop control in combination with heat load response and energy efficiency evaluation; After crude oil is produced from the oil well, it enters the oil storage and water reduction separator through the liquid inlet in a state of high water content (about 90%). Inside the separator, physical separation of the oil phase, water phase and gas phase is achieved through the control of the density difference and flow rate difference between oil and water. The upper gas phase is discharged and recovered through the exhaust port, and the bottom high-temperature water phase and the middle oil-containing liquid are respectively led out from the water outlet and the oil outlet; the discharged water phase is transported to the intermediate heat exchanger under the condition of less heat loss, and its sensible heat is transferred to the waste heat recovery multi-source heat exchange unit through the heat exchange process. After the water temperature drops from about 50°C to 40°C, it is pumped by the pumping pump to the formation recharge well. The recharge well is obtained by newly drilling or transforming an abandoned oil well, and its injection horizon is consistent with the oil production horizon, avoiding pollution of other formations and maintaining the formation pressure; at the same time, the intermediate oil phase from the separator is sent to the heating furnace through the oil outlet. Under the coordinated scheduling of the intelligent control unit, the heating furnace preferentially absorbs the heat from the waste heat recovery multi-source heat exchange unit, and sequentially calls renewable energy sources such as solar energy and air source heat pumps according to the oil temperature demand and the available state of the heat source to achieve coordinated temperature rise. After the oil temperature is raised from about 50°C to 60°C, it is transported to the joint station; in the above process, as the core scheduling module, the control unit real-time collects the oil temperature, flow rate, pressure and the output parameters of each heat source, dynamically calculates the heat source priority and conducts proportional scheduling, and at the same time establishes a heat load response model and an energy efficiency evaluation mechanism, and combines the heat exchange efficiency feedback to perform error closed-loop adjustment on the heat source output and the pump operation, so as to ensure the stability of the heating process, the maximization of energy efficiency and the intelligent adaptability of the system to the operating conditions.

[0022] As Figure 1 shown, the waste heat recovery multi-source heat exchange unit includes: A multi-stage heat exchanger, the first stage recovers the sensible heat of the water phase, and the second stage absorbs solar heat energy and air source heat energy; A water temperature control valve that automatically adjusts the water flow according to the pressure of the recharge well to meet: , where K = 0.5 - 1.2 is the well pressure correction coefficient, is the real-time data of the recharge well pressure sensor; The first stage of the multi-stage heat exchanger is a double spiral countercurrent tube. The inner tube of the double spiral countercurrent tube passes the water phase, and the outer tube passes the oil phase in the reverse direction; The advantage of this setting is to achieve the dual effects of energy cascade utilization and flow optimization. The double spiral countercurrent tube structure forms strong convective heat transfer through the reverse flow of the inner and outer tubes, so that the sensible heat released when the water phase temperature drops from 50°C to 40°C is efficiently absorbed by the oil phase (raising the oil temperature by 5 - 10°C), and the efficiency is increased by more than 70% compared with the traditional single tube heat exchanger; the water temperature control valve is based on the flow formula dynamically corrected by the well pressure , it can accurately maintain the balance of reinjection pressure, prevent water channeling caused by formation pressure fluctuations, and ensure that the heat exchanger always operates within the optimal Reynolds number range (2000 < Re < 5000), avoiding the decrease in heat transfer efficiency caused by laminar flow. The arrangement of the water phase flowing through the inner tube and the oil phase flowing through the outer tube utilizes the high viscosity characteristics of the oil phase. The secondary circulation generated by the spiral flow channel enhances the turbulence effect, increasing the heat transfer coefficient to 2.3 times that of traditional straight tubes and reducing the pumping energy consumption.

[0023] As Figure 1 shown, the waste heat recovery multi-source heat exchange unit includes a combined structure of a plate heat exchanger and a shell-and-tube heat exchanger, and a bypass valve group is set up. It can dynamically switch different heat exchange circuits according to the temperature difference and flow requirements of the inlet and outlet water to optimize the heat recovery efficiency; The plate heat exchanger is suitable for rapid heat exchange under large temperature difference conditions and can efficiently handle large flow fluids; the shell-and-tube heat exchanger is more suitable for stable heat exchange of small temperature difference and high viscosity fluids. The advantages of the two complement each other, significantly improving the heat recovery efficiency of the overall system. The intelligent bypass valve group can automatically adjust the flow path according to real-time working condition parameters, giving priority to using the plate heat exchanger when the temperature difference is large and automatically switching the pipeline when the flow fluctuates greatly, ensuring that the system is always in the best operating state, avoiding energy waste and ensuring heat exchange stability.

[0024] As Figure 1 、 Figure 4 shown, the heating furnace includes a heat source priority control strategy: (a) Give priority to calling waste heat as the main heat source, and the proportion of waste heat in the total heating energy is not less than 80%; (b) When the waste heat supply is insufficient, supplement other heat sources in the following order and proportion: ① Enable solar energy, and its supplement amount is 10% of the total required supplementary energy. At the same time, enable the air source heat pump, and its supplement amount reaches 90% of the total required supplementary energy; ② When the solar heat is insufficient, the air source heat pump's supplement amount reaches 100% of the total required supplementary energy; By mandating that the proportion of waste heat is not less than 80%, the stable supply of basic energy is ensured, meeting the rigid requirements of oilfield production for energy continuity. When the waste heat is insufficient, a two-level compensation mechanism of "solar energy first + heat pump backup" is adopted. When solar energy is available, it undertakes 10% of the supplementary amount (utilizing free energy and avoiding the risk of photovoltaic fluctuations), and the heat pump undertakes 90% simultaneously to form a reliable combination of "small photovoltaic regulation + large heat pump stability". When solar energy is insufficient, the fully controllable heat pump takes over 100%. This stepped compensation design not only ensures absolute energy stability in extreme situations (such as at night without light), but also reduces the heating cost by 10% when photovoltaic is available during the day.

[0025] As Figure 1As shown, the control unit includes an intelligent heat source collaborative scheduling module for use with the heating furnace, which is used to execute a dynamic energy distribution strategy; This module is used to automatically trigger dynamic compensation when the heat source fluctuates by more than ±15%. It is an emergency and dynamic adjustment mechanism, not a basic scheduling strategy under normal conditions. A static priority strategy (such as a heat source priority control strategy) is adopted during the normal operation stage. In the scenario of unstable heat sources or sudden increase in demand, the intelligent heat source collaborative scheduling module dynamically compensates and coordinates the loads of each heat source to ensure heating continuity and energy efficiency optimization. Specifically, the control unit monitors the waste heat supply in real time. When the fluctuation exceeds ±15%, solar thermal energy compensation and heat pump compensation are immediately started. The solar compensation quickly responds to sudden changes in light; the heat pump compensation is used to adapt to the heat conduction delay, and at the same time, the energy stability index is calculated. When S < 0.8, the energy storage buffer system (such as a molten salt tank or a backup battery pack) is automatically activated to temporarily fill the energy gap; the characteristics of solar energy (quick response) and heat pumps (periodic tuning) are respectively matched to solve the intermittency problem of renewable energy, compensate for the response speed, and control the temperature fluctuation. In addition, the energy stability index S quantifies the system safety margin, and the energy storage buffer intervenes in advance to avoid shutdown losses.

[0026] Such as Figures 1 to 3 As shown, the control unit has an error closed-loop regulation logic, including the following steps: S1: Collect the outlet oil temperature and the target temperature in real time, and calculate the temperature difference; S2: Determine whether the error tolerance is exceeded. If so, enter the compensation regulation; S3: Select one or more heat sources to participate in the regulation according to the compensation intensity level; S4: Recalculate the energy contribution rate and update the control coefficient every cycle; S5: If the error does not return to zero for more than three cycles, lock the heat source call ratio to the current effective range, and at the same time send a fault prompt signal; The control unit integrates a thermal energy abnormal response mechanism. When the output power fluctuation of any heat source exceeds 30%, the backfill pressure drops beyond the limit, or the heat exchange efficiency is lower than 75%, the following response process is triggered: enable the redundant heat source to temporarily replace the main heat source; record the characteristic code of the fault point and push the abnormal information to the remote control platform; if the abnormality is not resolved within three consecutive cycles, automatically switch to the full-load operation mode of the air source heat pump, and at the same time trigger an alarm signal; When the control unit executes error closed-loop regulation, it collects the outlet oil temperature of the heating furnace in real time, and collects the outlet oil temperature of the heating furnace in real time and the target temperature and then calculate the temperature difference When When the temperature difference ΔT > 1.5°C, compensation control is triggered. According to the value of ΔT, heat sources are activated in grades (solar energy is enabled at 1.5 - 2.0°C, solar energy + heat pump are linked at 2.0 - 3.0°C, and all heat sources cooperate when ΔT > 3.0°C). The energy contribution rate is updated every 45 - second cycle. If ΔT > 1°C does not recover for three consecutive cycles (135 seconds), the heat source call ratio is locked to the current effective range, and an audible and visual alarm is issued simultaneously. At the same time, when it is detected that the power fluctuation of any heat source exceeds 30% of the rated value, the backfill pressure suddenly increases by more than 20%, or the heat exchange efficiency is less than 75%, the air - source heat pump is immediately enabled to replace the faulty source. If the abnormality persists for three cycles without being eliminated, an alarm signal is triggered.

[0027] As Figure 1 As shown, the inlet of the oil - storage and water - reducing separator has an inlet baffle to stabilize the water flow and prevent the subsequent incoming liquid from disturbing the liquid in the tank. Inside the oil - storage and water - reducing separator, automatic separation is carried out by gravity according to the different densities of water, oil, and gas. The gas outlet controls the on - off of the gas pipeline through a pressure control valve. The pipelines of low - water - content crude oil and separated high - temperature sewage control the size of the external - transportation flow through a liquid - level control valve. The reinjection well meets the requirements of low - pressure reinjection and has a filtering device and a degassing device to stabilize the water flow, reduce the impurities and gas content of the reinjected sewage. The crude oil production fluid with a relatively high water content enters the oil - storage and water - reducing separator through the inlet pipe. First, the inlet baffle weakens the kinetic energy of the incoming liquid, preventing the high - speed liquid from directly impacting the liquid level inside the tank and causing liquid - level fluctuations or a decrease in separation efficiency. Subsequently, inside the tank, natural stratification separation occurs under the action of gravity due to the density differences of the oil, water, and gas phases. The gas floats to the top due to the lowest density and is discharged from the gas outlet equipped with a pressure control valve. This control valve automatically adjusts the gas release frequency according to the pressure change in the tank, preventing overpressure and avoiding energy waste. In the liquid part, the oil phase is in the middle, and the low - water - content crude oil is stably exported through the middle outlet by the liquid - level control valve to ensure a constant - flow of oil into the heating section. The separated water phase settles at the bottom due to the highest density and is transported to the subsequent intermediate heat exchanger and reinjection system through the bottom water outlet. Its flow rate is also dynamically regulated by the liquid - level control valve, making the overall external - transportation process stable without cavitation or backflow. At the same time, the reinjection well has the ability of low - pressure reinjection. It removes suspended particles and mechanical impurities through the built - in filtering device and releases residual gas through the degassing device, ensuring the purity and continuity of the injected fluid, avoiding impurity blockage of formation pores or gas formation causing gas blockage, improving the reinjection efficiency and ensuring formation safety. The system realizes three - phase separation while having functions such as pressure stability, precise liquid - level control, flow - balance regulation, and reinjected - water purification, thus significantly improving the oil - water separation quality, reducing the burden on subsequent equipment, and enhancing the system's safety and automatic operation ability.

[0028] Those of ordinary skill in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the present invention (including the claims) is limited to these examples; under the concept of the present invention, the technical features in the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations in different aspects of the present invention as described above, which are not provided in detail for the sake of brevity.

[0029] The present invention is intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. An oil production water reduction combined multi-source heating system, characterized in that, Including: An oil storage and water separation device, on one side of the top of which there is a liquid inlet, in the middle of the top there is an exhaust port, on one side of the bottom there are a water outlet and an oil outlet. The oil storage and water separation device is used to receive the produced liquid with high water content from the oil well, remove the water phase and gas phase through physical separation, output the intermediate oil phase with lower water content to the heating furnace, and the separated high-temperature water phase is transported to a multi-source heat pump unit for heat recovery. A waste heat recovery multi-source heat exchange unit, with one side connected to the oil production heating furnace. A heating furnace, which is connected to the oil outlet of the oil storage and water separation device, and there is a pumping pump body between the oil outlet and the heating furnace. The heating furnace can use the heat provided by the waste heat recovery multi-source heat exchange unit to increase the temperature of the exported crude oil. A reinjection well, which is a reformed abandoned oilfield well or a newly drilled well. The formation where the reinjection well reinjects sewage is consistent with the oil production layer to prevent pollution of other formation layers. An intermediate heat exchanger, with one side connected to the waste heat recovery multi-source heat exchange unit and the other side connected to the water outlet in the oil storage and water separation device. There is a pumping pump body between the intermediate heat exchanger and the waste heat recovery multi-source heat exchange unit. The intermediate heat exchanger is used to lower the temperature of the high-temperature water separated by the water separation device and then reinject it into the reinjection well. The waste heat recovery multi-source heat exchange unit uses the heat absorbed from the intermediate heat exchanger to heat the oil production heating furnace. A control unit, which is interconnected with the temperature sensors, flow meters, and pressure sensors in the waste heat recovery multi-source heat exchange unit, the heating furnace, and the oil storage and water separation device. It is used to dynamically calculate the heat source priority and coordinate the scheduling of each heat source according to the real-time heat source output, oil temperature demand, and reinjection pressure, and to provide real-time feedback on the heat exchange efficiency and perform closed-loop control in combination with the heat load response and energy efficiency evaluation.

2. The oil production and water reduction combined multi-source heating system according to claim 1, wherein The waste heat recovery multi-source heat exchange unit includes: A multi-stage heat exchanger, with the first stage recovering the sensible heat of the water phase and the second stage absorbing solar thermal energy and air source thermal energy. A water temperature control valve, which automatically adjusts the water flow according to the reinjection well pressure to meet: ， where K = 0.5−1.2 is the well pressure correction coefficient, and is the real-time data of the pressure sensor of the recharge well.

3. The oil production and water reduction combined multi-source heating system according to claim 2, wherein, The first stage of the multi-stage heat exchanger is a double spiral countercurrent tube, with the water phase flowing through the inner tube and the oil phase flowing reversely through the outer tube.

4. The oil production and water reduction combined multi-source heating system according to claim 1, wherein The waste heat recovery multi-source heat exchange unit includes a combined structure of a plate heat exchanger and a shell-and-tube heat exchanger, and a bypass valve group is provided, which can dynamically switch different heat exchange circuits according to the temperature difference and flow demand between the inlet and outlet to optimize the heat recovery efficiency.

5. The oil production and water reduction combined multi-source heating system according to claim 1, characterized in that, The heating furnace includes a heat source priority control strategy: a. Prioritize the use of waste heat as the main heat source, and the proportion of waste heat in the total heating energy is not less than 80%. b. When the waste heat supply is insufficient, supplement other heat sources in the following order and proportion: ① Enable solar energy, with its supplementary amount being 10% of the total required supplementary energy, and at the same time enable the air source heat pump, with its supplementary amount reaching 90% of the total required supplementary energy. ② When the solar heat is insufficient, the supplementary amount of the air source heat pump reaches 100% of the total required supplementary energy.

6. The oil production and water reduction combined multi-source heating system according to claim 5, wherein The control unit includes an intelligent heat source coordinated scheduling module for use with the heating furnace, which is used to execute the dynamic energy distribution strategy.

7. The oil production and water reduction combined multi-source heating system according to claim 6, wherein The control unit is equipped with an error closed-loop regulation logic, including the following steps: S1: Collect the oil outlet temperature and the target temperature in real time, and calculate the temperature difference; S2: Determine whether the error tolerance is exceeded. If so, enter the compensation regulation; S3: Select one or more heat sources to participate in the regulation according to the compensation intensity level; S4: Recalculate the energy contribution rate and update the control coefficient every cycle; S5: If the error does not return to zero for more than three cycles, lock the heat source call ratio to the current effective range, and at the same time send a fault prompt signal.

8. The oil production and water reduction combined multi-source heating system according to claim 7, wherein The control unit is integrated with a thermal energy abnormal response mechanism. When the output power fluctuation of any heat source exceeds 30%, the backfill pressure rises beyond the limit, or the heat exchange efficiency is lower than 75%, the following response process is triggered: enable the redundant heat source to temporarily replace the main heat source; record the fault point signature and push the abnormal information to the remote control platform; If the abnormality is not resolved within three consecutive cycles, it will automatically switch to the full-load operation mode of the air source heat pump, and at the same time trigger an alarm signal.

9. The oil production and water reduction combined multi-source heating system according to claim 1, wherein The inlet of the oil storage and water separation device has an inlet baffle for stabilizing the water flow and preventing the subsequent liquid inlet from disturbing the liquid in the tank. Inside the oil storage and water separation device, automatic separation is carried out by relying on the different densities of water, oil, and gas under the action of gravity. The gas outlet controls the on-off of the gas pipeline through a pressure control valve, and the low-water-content crude oil and the separated high-temperature sewage pipeline control the size of the external output flow through a liquid level control valve.

10. The oil production and water reduction combined multi-source heating system according to claim 1, characterized in that The reinjection well meets the requirements of low-pressure reinjection and is equipped with a filtering device and a degassing device for stabilizing the water flow and reducing the impurities and gas content of the reinjected sewage.

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