CN215892301U

CN215892301U - Thick oil thermal recovery steam injection system based on multi-energy complementation

Info

Publication number: CN215892301U
Application number: CN202122211031.XU
Authority: CN
Inventors: 白章; 郑博; 巩亮; 胡文鑫
Original assignee: China University of Petroleum East China
Current assignee: China University of Petroleum East China
Priority date: 2021-09-13
Filing date: 2021-09-13
Publication date: 2022-02-22
Anticipated expiration: 2031-09-13

Abstract

The present disclosure provides a thickened oil thermal recovery steam injection system based on multi-energy complementation, including: a geothermal subsystem, a solar subsystem, a wind energy subsystem and a steam production subsystem; the system comprises a geothermal subsystem, a steam production subsystem, a solar subsystem and a wind energy subsystem, wherein the geothermal subsystem comprises a primary heat pump and a secondary heat pump, the steam production subsystem comprises a first steam generator and a steam heat exchanger, the geothermal subsystem is in heat exchange connection with the steam production subsystem through the primary heat pump, the solar subsystem is in heat exchange connection with the first steam generator, and the wind energy subsystem is electrically connected with the steam heat exchanger; the geothermal subsystem is in heat exchange connection with the solar subsystem through a secondary heat pump; the wind energy subsystem is also electrically connected with the primary heat pump and the secondary heat pump respectively; the geothermal subsystem, the solar subsystem and the wind subsystem respectively generate geothermal energy, first energy and second energy with sequentially increased energy quality; the steam production subsystem is used for comprehensively and stepwisely utilizing geothermal energy, the first energy and the second energy to heat softened water in a segmented mode to produce steam.

Description

Thick oil thermal recovery steam injection system based on multi-energy complementation

Technical Field

The utility model relates to a viscous crude thermal recovery technical field especially relates to an supplementary viscous crude thermal recovery steam injection system based on multipotency source is complementary.

Background

The conventional steam injection heavy oil thermal recovery needs to consume a large amount of steam and steam to produce fuel, reduces the production energy consumption of the part, and plays an important role in improving the recovery efficiency and reducing the environmental pollution. Solar energy, wind energy and geothermal energy are widely utilized renewable resources at present, are inexhaustible in terms of reserves, have the advantages of being available on site, free of transportation and environment-friendly, and have wide prospects in the fields of auxiliary steam production and the like.

The solar energy utilization technology is mainly divided into two aspects of photovoltaic power generation and solar heat utilization. The solar heat utilization technology is used for converging dispersed solar radiation into radiant energy with a high light concentration ratio and providing high-temperature heat for a system. The heat collection is mainly divided into the following steps according to the light condensation form: disc type, tower type, groove type and linear Fresnel type. The parabolic trough collector is the most widely commercially available one, and the development of the parabolic trough collector is mature commercially. In the field of heavy oil thermal recovery, steam generation technology assisted by Solar trough power has begun to operate in some areas, wherein the GlassPoint Solar company in the united states has built a heavy oil thermal recovery commercial project dominated by Solar trough power in the middle east and california, etc. The solar steam generator is characterized in that the solar steam generator is greatly influenced by the environment, and meanwhile, the heat generated by the device is unstable due to seasonal period and day and night alternation, so that steam cannot be injected at a constant speed; the low intensity of solar radiation directly affects the economic efficiency of the device operation, so that equipment with higher heat collection efficiency is urgently needed to improve the economic efficiency of the device operation.

Wind energy is another form of solar energy with strong complementarity in the time-varying distribution. In the daytime, when the sunlight is the strongest, the wind power is smaller, and at night, the illumination is weak, but the wind energy is strengthened due to large surface temperature difference change; in summer, the sunlight intensity is high and the wind power is low, and in winter, the opposite is true. The time complementarity of solar energy and wind energy enables the solar energy and wind energy to have good matching property in resource utilization.

Geothermal energy is the natural heat energy extracted from the earth's crust in geological motion, which exists in the form of heat, and is the energy that causes volcanic eruptions and earthquakes. The temperature inside the earth can be as high as 7000 c, and at depths of 80-100km, the temperature drops to 650 c to 1200 c. Under significant pressure, high temperature heat energy is transferred to the formation at a location relatively close to the surface, heating the nearby groundwater to high temperatures, which eventually seep out of the surface and even out of the surface. The heat sources are directly taken to exchange heat in the heat exchanger, and the method is the simplest and most economical method. The technology of providing heat energy by combining electric energy and low-temperature geothermal energy has been gradually developed in the fields of domestic heating, agricultural production and the like. The development scale of geothermal energy represented by ground source heat pumps in China is in the leading position in the world.

Similar to geothermal resources, there is a large amount of waste heat of sewage in the process of heavy oil production. The oil extraction sewage is oil-containing sewage which is produced by extracting water, water condensed by injected steam or water existing in an original stratum along with crude oil when an oil field is exploited. The temperature level is mostly distributed at 45-65 ℃, and the method is closely related to oil field production. Compared with the conventional geothermal resources, the waste heat of the sewage does not need additional drilling engineering and tail water recharging engineering investment, and the cost of hot water extraction and tail water recharging can be saved. And the modern oil extraction process stably controls the water quality of the sewage, has weak tendency of corrosion and scaling after treatment, and is an energy source with potential comprehensive utilization.

The problems of huge energy consumption, serious environmental pollution and the like exist in the field of thickened oil thermal recovery, and meanwhile, rich renewable resources and waste heat resources exist in thickened oil development areas. From the viewpoint of stability, the wind energy and the solar energy fluctuate along with time, the geothermal energy is very stable, and the wind energy, the solar energy and the geothermal energy are sequentially decreased in energy grade. Therefore, the thickened oil thermal recovery steam injection system which complementarily utilizes wind, light and geothermal energy can not only greatly reduce the damage of direct combustion of fuel to the ecological environment, but also comprehensively utilize high-grade development of wind energy and low-grade geothermal and waste heat, promote the development and utilization of new energy, and has good development prospect.

SUMMERY OF THE UTILITY MODEL

Technical problem to be solved

In view of the prior art, the present disclosure provides a thickened oil thermal recovery steam injection system based on multi-energy complementation, which is used to at least partially solve the above technical problems.

(II) technical scheme

The present disclosure provides a thickened oil thermal recovery steam injection system based on multi-energy complementation, including: a geothermal subsystem, a solar subsystem, a wind energy subsystem and a steam production subsystem; the system comprises a geothermal subsystem, a steam production subsystem, a solar subsystem and a wind energy subsystem, wherein the geothermal subsystem comprises a primary heat pump and a secondary heat pump, the steam production subsystem comprises a first steam generator 4 and a steam heat exchanger, the geothermal subsystem is in heat exchange connection with the steam production subsystem through the primary heat pump and is used for carrying out primary heating on softened water, the solar subsystem is in heat exchange connection with the first steam generator 4 and is used for carrying out secondary heating on the softened water, and the wind energy subsystem is electrically connected with the steam heat exchanger and is used for carrying out tertiary heating on the softened water; the geothermal subsystem is in heat exchange connection with the solar subsystem through a secondary heat pump; the wind energy subsystem is also electrically connected with the primary heat pump and the secondary heat pump respectively; the system comprises a geothermal subsystem, a solar subsystem and a wind subsystem, wherein the geothermal subsystem, the solar subsystem and the wind subsystem respectively generate geothermal energy, first energy and second energy; the energy quality of the geothermal energy, the first energy and the second energy is increased in sequence, and the steam production subsystem is used for comprehensively and stepwisely utilizing the geothermal energy, the first energy and the second energy to heat softened water in a segmented mode to produce steam.

Optionally, the geothermal subsystem further comprises: an underground mining device 6 and a three-stage heat pump; the underground mining device 6 is used for mining geothermal energy and inputting the geothermal energy into the three-level heat pump; the primary heat pump comprises a first condenser 11, a secondary evaporator 8, a first compressor 10 and a first throttle valve 12; the secondary evaporator 8 is in heat exchange connection with the tertiary heat pump, and is used for absorbing heat energy of geothermal energy and using the heat energy for evaporation of heat pump cycle media, the geothermal subsystem is in heat exchange connection with the steam production subsystem through the first condenser 11, the first compressor 10 is electrically connected with the wind energy subsystem and is used for improving pressure of the heat pump cycle media, energy quality of the geothermal energy is improved through the second energy, a first mixed energy is obtained, and the first throttle valve 12 is used for reducing pressure of the heat pump cycle media output by the first condenser 11.

Optionally, the steam production subsystem further comprises a preheater 7, and the tertiary heat pump is further in heat exchange connection with the preheater 7.

Optionally, the secondary heat pump comprises: a second evaporator 13, a second compressor 14, a second condenser 15, and a second throttle valve 16; the second evaporator 13 is in heat exchange connection with the primary heat pump and used for absorbing heat energy of the first mixed energy and using the heat energy for evaporation of a circulating working medium of the secondary heat pump, the second compressor 14 is electrically connected with the wind energy subsystem and used for improving the pressure of the circulating working medium of the heat pump and improving the energy quality of the first mixed energy by using the second energy to obtain second mixed energy, the second condenser 15 is in heat exchange connection with the solar subsystem and used for storing the second mixed energy to the solar subsystem, and the second throttle valve 16 is used for reducing the pressure of the circulating working medium of the heat pump output by the second condenser 15; the second condenser 15 is also in heat exchange connection with a steam heat exchanger.

Optionally, the solar subsystem comprises: a solar heat collector 1 and a heat storage device; the solar heat collector 1, the heat storage device and the first steam generator 4 are connected with each other through a tee joint, the second condenser 15 is in heat exchange connection with the heat storage device, and the heat storage device is used for storing and releasing high-temperature working media after absorbing geothermal energy, the first energy and the second energy and low-temperature working media after heat exchange.

Optionally, the heat storage device comprises: a high-temperature storage tank 2 and a low-temperature storage tank 3; wherein, the heat pump cycle working medium flows out from the low-temperature storage tank 3, exchanges heat with the second condenser 15 and then flows into the high-temperature storage tank 2.

Optionally, the wind energy subsystem comprises: a wind generating set 19, an electric control device 20 and a control center 25; wherein, the wind generating set 19 is electrically connected with the electric control device 20, the steam heat exchanger, the primary heat pump and the secondary heat pump respectively; the electric control device 20 is in communication with the control centre 25 for controlling the second energy source to heat the softened water three times and to improve the energy quality of the geothermal energy source and to connect to an external power grid 21.

Optionally, the geothermal subsystem further comprises a produced wastewater water supply S2; the primary heat pump further comprises a primary evaporator 9, the primary evaporator 9 is in heat exchange connection with the oil extraction sewage water supply device S2 and used for absorbing the waste heat of the oil extraction sewage, and the energy quality of the waste heat of the oil extraction sewage is improved by utilizing a second energy in the circulation of the primary heat pump, so that a first mixed energy is obtained.

Optionally, the steam heat exchanger comprises: a second steam generator 22 and a steam superheater 23; the steam production subsystem further comprises: a control valve; wherein the second steam generator 22 and the steam superheater 23 are used for heating the softened water for three times by using the second energy source, and the control valve is used for controlling the geothermal energy source, the utilization ratio of the first energy source and the second energy source, and the generated steam flow.

(III) advantageous effects

The utility model provides a thickened oil thermal recovery steam injection system based on multi-energy complementation, compared with the prior art, the thickened oil thermal recovery steam injection system at least has the following beneficial effects:

(1) through comprehensive gradient utilization of geothermal energy, solar energy and wind energy, the characteristics of stability of geothermal energy, high energy grade of solar energy and wind energy and the like can be fully exerted, damage of direct combustion of fuel to the ecological environment is greatly reduced, and the utilization efficiency of various renewable energy sources is improved.

(2) The heat pump mode is adopted to combine the electric energy generated by wind power, low-temperature geothermal energy and the residual heat energy of the oil extraction sewage, so that the grade of the low-temperature heat energy is improved, and the full utilization of different grades of energy sources is realized.

(3) The fluctuation of wind energy and solar energy is reduced through various heat storage modes, heat energy and electric energy in a distribution system can be flexibly controlled according to production requirements, the technical flexibility is high, the adaptability is strong, the stable operation of the system operation is guaranteed, and the system can be well popularized and applied.

Drawings

The above and other objects, features and advantages of the present disclosure will become more apparent from the following description of embodiments of the present disclosure with reference to the accompanying drawings, in which:

FIG. 1 schematically illustrates a composition diagram of a heavy oil thermal recovery steam injection system based on multi-energy complementation according to an embodiment of the disclosure;

FIG. 2 schematically illustrates a system energy cascade utilization schematic in accordance with an embodiment of the disclosure;

FIG. 3 schematically illustrates an operational control subsystem block diagram according to an embodiment of the present disclosure.

[ description of reference ]

1-solar heat collector

2-high temperature storage tank

3-low temperature storage tank

4-first steam generator

5-first working medium circulating pump

6-underground mining device

7-preheater

8-two-stage evaporator

9-first-stage evaporator

10-first compressor

11-first condenser

12-first throttle valve

13-second evaporator

14-second compressor

15-second condenser

16-second throttle valve

17-water storage tank

18-water supply pump

19-wind generating set

20-electric control device

21-external grid

22-second steam generator

23-steam superheater

24-steam injection well

25-control center

26-oil extraction machine

27-second working medium circulating pump

28-third working medium circulating pump

29-first control valve

30-second control valve

31-third control valve

32-fourth control valve

33-fifth control valve

34-sixth control valve

35-seventh control valve

A-first control Module

B-second control Module

C-third control module

D-fourth control Module

S1-softened water supply device

S2-oil extraction sewage water supply device

Detailed Description

For the purpose of promoting a better understanding of the objects, aspects and advantages of the present disclosure, reference is made to the following detailed description taken in conjunction with the accompanying drawings.

It should be noted that in the drawings or description, the same drawing reference numerals are used for similar or identical parts. Features of the embodiments illustrated in the description may be freely combined to form new embodiments without conflict, and each claim may be individually referred to as an embodiment or features of the claims may be combined to form a new embodiment, and in the drawings, the shape or thickness of the embodiment may be enlarged and simplified or conveniently indicated. Further, elements or implementations not shown or described in the drawings are of a form known to those of ordinary skill in the art. Additionally, while exemplifications of parameters including particular values may be provided herein, it is to be understood that the parameters need not be exactly equal to the respective values, but may be approximated to the respective values within acceptable error margins or design constraints.

Unless a technical obstacle or contradiction exists, the above-described various embodiments of the present disclosure may be freely combined to form further embodiments, which are all within the scope of protection of the present disclosure.

While the present disclosure has been described in connection with the accompanying drawings, the embodiments disclosed in the drawings are intended to be illustrative of the preferred embodiments of the disclosure, and should not be construed as limiting the disclosure. The dimensional proportions in the drawings are merely schematic and are not to be understood as limiting the disclosure.

Although a few embodiments of the present general inventive concept have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the general inventive concept, the scope of which is defined in the claims and their equivalents.

The term "heat exchange connection" in the present disclosure refers to a connection manner of heat exchange between different systems or devices through pipes or other devices in contact with or close to each other. "electrically connected" refers to the manner in which a power generation system is associated with supplying power to a power consuming system.

Fig. 1 schematically shows a composition diagram of a heavy oil thermal recovery steam injection system based on multi-energy source complementation according to an embodiment of the disclosure.

According to the embodiment of the present disclosure, as shown in fig. 1, a heavy oil thermal recovery steam injection system based on multi-energy source complementation, for example, includes: and the geothermal subsystem is used for providing geothermal energy. A solar subsystem for converting solar energy into a first energy source. And the wind energy subsystem is used for converting wind energy into a second energy source. And the steam production subsystem is used for comprehensively and stepwisely utilizing the geothermal energy, the first energy and the second energy to heat softened water in a segmented manner to produce steam. The energy quality of the geothermal energy source, the first energy source and the second energy source is increased in sequence, and the second energy source is also used for improving the energy quality of the geothermal energy source. The first energy source is, for example, thermal energy converted from solar energy and the second energy source is, for example, electrical energy converted from wind energy. The quality of the heat energy can be measured by the temperature.

According to the embodiment of the present disclosure, the geothermal subsystem can provide stable and reliable medium-low temperature heat energy for the system, as shown in fig. 1, the geothermal subsystem includes, for example, an underground mining device 6, a first working medium circulating pump 5, a preheater 7, a secondary evaporator 8 constituting a primary heat pump cycle of a ground source heat pump, a primary evaporator 9, a first compressor 10, a first condenser 11 and a first throttle valve 12, and a second steam generator 13, a second compressor 14, a second condenser 15 and a second throttle valve 16 constituting a secondary heat pump cycle of a ground source heat pump.

The underground mining device 6 is used for mining the geothermal energy of the middle-deep layer and lifting the geothermal energy to the ground through working media such as geothermal water and the like. The underground mining device 6 is, for example, a heat-collecting shaft, an insulating layer is covered outside the shaft, and the heat-conducting working medium is utilized to circulate in the sleeve to extract geothermal energy such as sedimentary rock heat energy in a middle-deep layer range to the ground. The first working medium circulating pump 5 drives the heat-conducting working medium to circulate by utilizing mechanical energy or electric energy provided by the system. The ground source heat pump improves low-grade geothermal energy into higher-temperature heat energy, and provides higher-grade heat energy resources for steam production.

According to the embodiment of the disclosure, the ground device utilizes geothermal energy by adopting two utilization modes, namely a direct heat exchange mode and a double-stage heat pump mode. The direct heat exchange method can be, for example: the produced geothermal temperature is about 50-150 ℃, and from the economical point of view, the low-temperature softened water supplied by the softened water supply device S1 is preheated by adopting a direct heat exchange mode. A portion of the heat energy produced in the underground mining installation 6 is passed through the third control valve 31 into the demineralized water preheater 7 for direct heating of the demineralized water. The complexity of system equipment can be reduced by adopting a direct heat exchange mode, and the economical efficiency of the system is improved.

The heat pump utilization may be, for example: the two-stage evaporator 8, the one-stage evaporator 9, the first compressor 10, the first condenser 11 and the first throttle valve 12 constitute a one-stage heat pump, and the second evaporator 13, the second compressor 14, the second condenser 15 and the second throttle valve 16 constitute a two-stage heat pump. For example, a part of geothermal energy produced by geothermal exploitation and waste heat of sewage separated in the crude oil exploitation process are respectively absorbed by a secondary evaporator 8 and a primary evaporator 9, the heat energy is transferred to a heat pump circulating working medium, the heat pump circulating working medium absorbs heat and then evaporates into a gas state, and then enters a first compressor 10, the electric energy provided by a wind energy subsystem, namely the first compressor 10 driven by a second energy source, improves the pressure of the heat pump circulating working medium, the second energy source is utilized to improve the heat energy grade of the geothermal energy and the waste heat of the oil extraction sewage, a first mixed energy source is formed, and the energy quality of the geothermal energy and the waste heat of the oil extraction sewage is improved while the oil extraction sewage is recovered. The compressed high-temperature working medium enters the first condenser 11 to release heat, and the heat energy is used as a primary heating heat source for softening water. The heat pump circulating working medium is condensed in the first condenser 11 to release heat, then is throttled by the first throttle valve 12, and the decompressed heat pump circulating working medium enters the secondary evaporator 8 and the primary evaporator 9 again to realize heat pump circulation.

When the second energy is sufficient, the first mixed energy can be used for providing a primary heating heat source for steam production, and the second mixed energy can be used for providing a secondary heating heat source for steam production.

The working medium circulation process of the second-stage heat pump heating is similar to that of the first-stage heat pump, and the heat pump circulating working medium is evaporated after absorbing the medium-temperature heat energy of the first mixed energy through the second evaporator 13 and enters the second compressor 14 to increase the pressure and the temperature. And the second energy provided by the wind power generation subsystem is utilized to promote the first hybrid energy into second hybrid energy with higher quality. The high-temperature circulating working medium releases heat and condenses in the second condenser 15, and the second mixed energy is used for secondary heating of steam production or is stored in a high-temperature storage tank. Finally, the heat pump cycle working medium is depressurized through a second throttle valve 16 and returns to the second evaporator, thereby forming a heating cycle.

The difference between the secondary heat pump cycle and the primary heat pump cycle is that the heat released by the primary heat pump cycle is used as a low-temperature heat source of the working medium in the secondary heat pump cycle, and the heat energy temperature of the second mixed energy generated by the secondary heat pump cycle is higher than that of the primary heat pump, so that the secondary heat pump can be used for secondary heating in the steam production process, and can also be used as high-quality heat energy to be stored in a high-temperature storage tank 2, wherein the high-temperature storage tank 2 is a heat storage tank, for example.

According to the embodiment of the disclosure, the heat recovery well used by the underground mining device 6 is similar to the oil recovery well and the steam injection well 24 in structure, and the outside of the well barrel is covered with an insulating layer. In different stages of thermal recovery, the steam injection/production wells often need to be built in batches, while the production/injection wells in earlier projects are often left unused at a later stage. Therefore, the underground mining device 6 can fully utilize the resources of the abandoned well, transform or directly utilize the existing steam injection well/oil extraction well as a geothermal collecting well of later engineering, and can reduce the system construction cost.

According to the embodiment of the disclosure, considering that the wind power generation amount fluctuates continuously along with time and the geothermal energy is relatively stable, the geothermal resource can provide corresponding thermal load for the system as required, and the geothermal subsystem can adopt different operation load strategies according to the change of the wind power generation power:

the minimum load, which is supplemented by the external power grid 21 for example when the wind power generation is low or missing, comprises the minimum power consumption of the first working medium circulation pump 5 and the first compressor 10. In the utilization of geothermal energy, for example, the preheater 7 is designed for a fixed heat load, and the minimum heat energy required by the secondary evaporator 8 is controlled, for example, by the operation control subsystem.

And when the wind power generation amount is in a normal range, the basic load is used, because the temperature difference of the secondary heat pump is high, the heating efficiency is relatively low, the secondary heat pump stops running, only the primary heat pump runs, and the energy utilization efficiency of the system is improved. And determining the load of the first compressor 10 and the flow of the first working medium circulating pump 5 according to the wind power generation capacity.

The maximum load is that when the wind power generation capacity is abundant or the solar subsystem is insufficient in heat energy supply, the heat load of steam production is mainly provided by electric energy and geothermal energy, the exploitation amount of the geothermal energy is obviously increased compared with the basic load, the primary heat pump and the secondary heat pump run simultaneously, one part of the intermediate temperature heat energy of the first mixed energy obtained by the primary heat pump is used for heating softened water through the first condenser 11, and the other part of the intermediate temperature heat energy is used as the low temperature heat source of the secondary heat pump in the second evaporator 13 (the evaporator of the secondary heat pump). In the secondary heat pump cycle, the medium-temperature heat energy is promoted to be higher-temperature heat energy, namely a second mixed energy source, and is used in a secondary heating stage with higher requirement on the quality of a heat source in the steam production process, or the heat storage working medium is heated to store wind energy and geothermal energy into high-temperature heat energy, so that the complementary storage of high-grade and low-grade energy sources is realized.

According to an embodiment of the present disclosure, the solar subsystem obtains clean thermal energy, i.e. the first energy source, for example, using trough solar collection technology. As shown in fig. 1, the solar subsystem is composed of, for example, a solar collector 1, a first steam generator 4, a heat storage device (high-temperature storage tank 2, low-temperature storage tank 3 being, for example, a cooling tank), a second working medium circulation pump 27 and a third working medium circulation pump 28. The solar collector 1 is for example a trough solar collector. Trough solar collectors include, for example: the trough type solar heat collecting mirror field is composed of a plurality of parabolic trough type light and heat collecting units, and each unit comprises a trough type condenser (a condenser), a vacuum heat collecting pipe (a heat collector), a tracking driving device and the like. The inner wall of the solar heat collecting pipe, namely the vacuum heat collecting pipe, is coated with a radiation absorption coating, and an interlayer of the inner pipe and the outer pipe is a vacuum heat insulating layer, for example. The solar heat collecting mirror field is used for collecting solar radiant energy with large area and low energy quality into radiant energy with certain area and high energy quality. The solar heat collecting pipe is used for converting solar radiation energy with high energy quality into high-temperature heat energy and transferring the heat energy to heat conducting working media or water vapor. The tracking driving device is controlled by the control module A, for example, and tracks the solar radiation light source in real time.

According to the embodiment of the present disclosure, the solar subsystem provides heat energy for steam production through working medium circulation after absorbing solar radiation energy and transferring the solar radiation energy to the heat-conducting working medium by the solar heat collector 1. The solar subsystem can convert redundant solar heat collection or other redundant energy of the system into heat energy to be stored in the heat storage device so as to adjust the heat energy supply fluctuation of the system. Solar radiation is converged to the inner pipe wall of the vacuum heat collecting pipe through the groove type condenser, converted into heat energy and then transmitted to the heat conducting working medium. The heat conducting working medium can be molten salt, heat conducting oil, metal and alloy thereof. The heat-absorbed high-temperature working medium is driven by a second working medium circulating pump 27, the high-temperature working medium is controlled by a first control valve 29 to enter the first steam generator 4 to release heat energy, and the heat-exchanged low-temperature working medium enters the groove type mirror field again to circulate. The high-temperature working medium after heat absorption by the groove type condenser field can be stored by system control. The heat storage part adopts a method of double-tank heat storage by using a high-temperature storage tank 2 and a low-temperature storage tank 3, for example, the heated high-temperature working medium is stored in the high-temperature storage tank 2, and the heat-exchanged low-temperature working medium is stored in the low-temperature storage tank 3. Examples of heat storage materials include water vapor, heat transfer oil, concrete, molten salts, metals and their alloys.

Preferably, molten salt or heat conducting oil is used as a heat conducting and storing working medium to absorb solar radiation heat energy in the groove type heat collecting mirror field.

According to the embodiment of the present disclosure, according to the energy scheduling requirement of the system, for example, the system may be controlled to adjust the working states of the second working medium circulation pump 27 and the first and

second control valves

29 and 30 to switch different working medium flow modes to realize heat storage and heat release of solar energy:

heat storage and flowing: when the solar radiation heat collection amount, i.e. the first energy, is larger than the heat load demand of the first steam generator 4, the working medium pump transmits the heat conducting working medium from the outlets of the low-temperature storage tank 3 and the first steam generator 4 to the mirror field to absorb the solar radiation heat by adjusting the second control valve 30, then the heated working medium is divided into two parts by the first control valve 29, one part meets the heat demand of steam production through the first steam generator 4, and the other part of the high-temperature working medium is transmitted to the high-temperature storage tank 2 to store heat.

Exothermic flow: contrary to the working fluid in the regenerative flow mode, heat energy is released from the high temperature storage tank 2 when the solar radiation heat collection, i.e. the first energy source, is less than the heat load demand of the first steam generator 4. The working medium of the heat collecting mirror field and the working medium of the high-temperature storage tank 2 jointly flow into the first steam generator 4 by adjusting the first control valve 29, the working medium after heat exchange is divided into two parts by the second control valve 30, one part flows into the low-temperature storage tank 3, and the other part enters the groove type heat collecting mirror field to be circulated again.

The heat pump stores heat and flows: the low-temperature heat storage working medium in the low-temperature storage tank 3 is driven by a third working medium circulating pump 28 to enter a second condenser 15 of the secondary heat pump to absorb heat energy and then enter the high-temperature storage tank 2 to be stored. The heat pump heat storage flow and the heat storage flow can be operated simultaneously.

According to an embodiment of the present disclosure, as shown in fig. 1, a wind energy subsystem comprises, for example: a wind generating set 19, an electric control device 20 and an external power grid 21. Among these, the wind power generator unit 19 is, for example, a horizontal axis wind power generator unit, and each wind power generator includes, for example: impellers, gearboxes, generators, towers, etc., for collecting wind energy and converting mechanical energy into electrical energy usable by the system. The electric control device 20 is composed of, for example, a controller, a transformer, an inverter, a power transmission line, and the like, and is responsible for controlling wind power conversion, power transmission, and reasonable allocation with the external power grid 21. The wind generating set 19 converts wind power energy into electric energy, i.e. a second energy source, and a part of the generated electric energy (the second energy source) is used in the geothermal subsystem (for example, used for driving the first compressor 10, the second compressor 14 and the first working medium circulating pump 5), and the other part of the generated electric energy (the second energy source) is used for power consumption of electric equipment (for example, the second steam generator 22 and the steam superheater 23) in the steam production subsystem, so as to meet the power demand of the system. The fluctuation of the wind power generation amount can be matched by adjusting different load modes by the geothermal subsystem. When the electric power (second energy) is extremely deficient, the system power utilization can be supplemented through the external power grid 21, and correspondingly surplus wind power can also transmit power to the external power grid 21. The electric energy (second energy) of the wind energy subsystem is a heat energy source for tertiary heating, and meanwhile, the electric energy of the wind energy subsystem is also indirectly used as an energy source for primary heating and secondary heating through the primary heat pump and the secondary heat pump.

According to an embodiment of the present disclosure, as shown in fig. 1, the steam generation subsystem includes, for example, a water storage tank 17, a feedwater pump 18, a preheater 7, a first condenser 11, a first steam generator 4, a second steam generator 22, a steam superheater 23, and a control valve. The water storage tank 17 is used, for example, to store softened water that meets steam production standards. The feed pump 18 is used to provide the pressure required for the heavy oil thermal recovery injection steam. The control valve includes, for example: the first control valve 29, the second control valve 30, the third control valve 31, the fourth control valve 32, the fifth control valve 33, the sixth control valve 34 and the seventh control valve 35 are used for changing the steam flow and the steam production mode so as to match the steam production heat load with the system energy supply.

The production of steam for example uses a tertiary heating mode: the primary heating is carried out by the geothermal subsystem through the direct heating of the preheater 7 and the heating (the heating by the first mixed energy source) through the first condenser 11 in the heat pump, the secondary heating is mainly carried out by the first steam generator 4 by utilizing the radiant heat energy (the first energy source) of the solar subsystem, and the tertiary heating is carried out by mainly utilizing the electric energy (the second energy source) of the wind energy subsystem to drive the second steam generator 22 and the steam superheater 23 for heating. The high-temperature steam obtained by the primary heating, the secondary heating and the tertiary heating is injected into the underground heavy oil through the steam injection well 24, for example, to improve the oil recovery efficiency of the oil recovery machine 26.

FIG. 2 schematically illustrates a system energy cascade utilization schematic in accordance with an embodiment of the disclosure.

According to an embodiment of the present disclosure, as shown in fig. 2, the energy quality of wind power, solar heat and geothermal energy (and oil extraction wastewater residual heat) is reduced in sequence. In an ideal situation, the steam production process can comprehensively utilize solar radiation energy, wind energy, geothermal energy and oil extraction sewage waste heat, and the advantages of different energy qualities are fully exerted. In the primary heating, the geothermal energy can firstly carry out primary preheating on the softened water through the preheater 7, one part of the geothermal energy is utilized in the most economical mode, and the other part of the geothermal energy and the waste heat of the oil extraction sewage supplied by the oil extraction sewage water supply device S2 are used as subsequent heating sources after being lifted to the first mixed energy source with higher heat quality through heat pump circulation. The primary heating is used as a medium-low temperature heating process, the heat energy in each temperature range is utilized in a gradient mode, and the advantage that wind energy is used as high-quality energy is fully exerted by utilizing a heat pump. The secondary heating utilizes the solar heat energy (first energy) absorbed in the heat collecting mirror field as the main heat source of the middle and high temperature section, and the high temperature storage tank 2 can make up the deficiency of the solar heat collecting energy (first energy) at night. The third heating is driven by electric energy, for example, wind power electric energy (second energy) is used as a main heat source of the high-temperature section, thermal parameters of steam are improved in the second steam generator 22 and the steam superheater 23, the characteristic of flexible electric energy scheduling is fully exerted, and the quality of injected high-temperature steam is ensured. The steam production subsystem comprehensively utilizes various heat energy provided by the system, and adopts a multi-section heating mode to cascade utilize energy sources with different qualities to produce steam meeting the requirements.

According to the embodiment of the disclosure, various energy supply subsystems and various energy consumption subsystems need to be regulated and controlled in real time to meet different meteorological conditions and production requirements. The heavy oil thermal recovery steam injection system based on multi-energy source complementation also comprises an operation control subsystem, for example, the operation control subsystem comprises various sensors, a central controller, control valves and other equipment control devices. As shown in fig. 3, the operation control subsystem includes, for example, A, B, C, D four control modules, which are used to properly schedule the system energy to match the steam production process by monitoring the steam injection parameters required by the production process in real time, in combination with the meteorological conditions and the system energy storage conditions. The first control module a can be used to adjust the light-gathering angle of the solar collector 1 in the solar subsystem, and adjust the heat energy utilization and storage process of the solar subsystem according to the system requirement. The second control module B may for example be used to regulate the wind power generation process, scheduling system power usage according to production needs. The third control module C may for example be used to control geothermal production of a geothermal subsystem and the cycling process of a ground source heat pump. The fourth control module D may be used, for example, to adjust the heat load of steam production and the complementary relationship of system electrical energy, geothermal energy, solar radiant heat energy. The operation control subsystem is in communication connection with the control center 25, and the control center 25 controls the operation of each subsystem in a unified manner.

Specifically, the first control module a, for example, adopts a sun-viewing trajectory tracking, and the external radiation sensor continuously collects the incident angle and the radiation intensity of solar energy at each time, and outputs a tracking signal after being processed by the control center 25, so as to drive the tracking device to adjust the mirror field tracking angle, thereby ensuring the optimal heat collection efficiency. Meanwhile, the heat collection amount of solar energy can be predicted according to the solar irradiation intensity condition, and the second working medium circulating pump 27, the first control valve 29 and the second control valve 30 are adjusted in time in combination with the heat load required by the first steam generator 4 to control the flow and the circulating mode of the heat conducting working medium, so that the heat storage and discharge control of the heat storage module is completed. The heat storage and release methods are described in the solar subsystem and will not be described herein.

The second control module B can regulate the wind energy subsystem, and can control the operation of the wind turbine generator system 19 according to the wind power, and the generated electric energy can be regulated and transmitted by the electric control device 20, for example, the electric load of the first compressor 10, the second compressor 14 and the first working medium circulating pump 5 is preferably satisfied, the surplus electric quantity can be transmitted to the external power grid 21, and the electric energy input from the external power grid 21 can be controlled when the power supply of the wind energy subsystem is insufficient. The electric energy dispatching method is already described in the wind energy subsystem, and is not described herein again.

The third control module C adjusts the geothermal subsystem, and can adjust the flow rate of the first working medium circulating pump 5 according to the amount of electric energy generated by wind power generation, so as to control the exploitation amount of geothermal energy.

The fourth control module D controls the steam production process, and can reasonably match the energy supply of each heating stage in the steam production according to the fluctuation conditions of wind power and solar radiation heat energy. The specific energy scheduling method will be described in the steam production subsystem, and will not be described herein.

According to the embodiment of the disclosure, the subsystems can be coordinated and complemented with each other by the operation control subsystem in a coordinated manner, for example, in consideration of instability of wind energy and solar energy and fluctuation with time. The operation control subsystem adopts a multi-objective optimization algorithm, for example, and simultaneously optimizes a plurality of objectives of the solar subsystem and the wind power generation subsystem, such as energy utilization efficiency, heat storage efficiency, system overall energy utilization efficiency and steam production parameters, and implements an energy scheduling process. And in the operation strategy, the steam production is stably carried out, and meanwhile, the energy utilization efficiency and exergy efficiency of the system are maximized. Through mutual complementation among geothermal energy, solar energy and wind energy, fluctuation is adjusted to enable wind, light and geothermal energy resources to meet the energy requirement of the steam production subsystem, meanwhile, the solar energy subsystem can store surplus energy in the energy storage device in a thermal energy mode, and releases thermal energy in the energy storage device for complementation when other energy is insufficient, so that the fluctuation of energy supply is reduced. Wind power electric energy which is high in energy quality, but unstable and difficult to store is preferentially utilized, fluctuation of wind energy and solar heat energy is absorbed in modes of directly adjusting electric energy load, indirectly supplementing heat energy and the like, and the wind power electric energy and geothermal energy are preferentially combined by utilizing a heat pump, so that the advantage of high-quality energy is fully exerted.

According to the embodiment of the present disclosure, the steam production process needs to be dynamically adjusted in real time according to the change of meteorological conditions and the requirement of steam production heat load of the system, and the following operation modes can be classified according to different operation states.

According to embodiments of the present disclosure, during daytime, there may be situations where the solar energy (first energy source) is too much and the wind power generation (second energy source) is insufficient. The heat load for the steam production in the high-temperature section is then largely provided, for example, by the first steam generator 4. For example, the sixth control valve 34 and the seventh control valve 35 are adjusted to close the passage of the steam through the second condenser 15, the circulation flow rate of the heat-conducting working medium in the first steam generator 4 is increased, the heat load of the secondary heating is increased, and a small amount of electric energy (second energy) generated by the wind energy subsystem can be used for the tertiary heating of the steam, so that the real-time adjustment of steam parameters is ensured. In the primary heating process, the power consumption of the first compressor 10 of the heat pump is properly reduced according to the supply of the wind power generation amount, and the circulation flow of the first working medium circulating pump 5 is correspondingly reduced so as to reduce the electric load. The steam production process is, for example: the water storage tank 17 is pressurized by the feed pump 18, and then passes through the preheater 7, the first condenser 11, the first steam generator 4, the second steam generator 22 and the steam superheater 23 in sequence to become superheated steam, and finally is injected into the well.

According to the embodiments of the present disclosure, when there occurs a situation where solar radiation thermal energy (first energy) is insufficient and wind power generation (second energy) is increased, steam production is mostly provided by, for example, one heating and three heats in a high temperature section. In this case, a complementary flow of heat storage can be used in the solar subsystem to supplement the heat load requirement of the first steam generator 4 in the secondary heating stage. Part of the electric energy (second energy) generated by the wind energy subsystem is used for heating for three times, part of the electric energy is supplied to a load of a heat pump in the geothermal subsystem, and the rest of the electric energy can be boosted by the electric control device 20 and then input into an external power grid 21, so that the full utilization of the electric energy is ensured. The geothermal subsystem can obtain sufficient electric energy to ensure stable one-time heating. The steam production process is, for example: the water storage tank 17 is pressurized by the feed pump 18, then sequentially passes through the preheater 7 and the first condenser 11, is shunted to the first steam generator 4 and the second condenser 15 through the control valve 34, then converges to the second steam generator 22 and the steam superheater 23 through the control valve 35 to become superheated steam, and finally is injected into the well.

According to an embodiment of the present disclosure, when a complete loss of thermal energy from the solar subsystem occurs, the thermal load to the system is provided by, for example, geothermal energy and electrical energy, and the full electrical energy can still be provided by the external grid 21 even under extreme meteorological conditions where wind power generation is completely lost. At the moment, the wind energy subsystem supplements electric energy through an external power grid 21, and guarantees the electric loads of a steam generator 22 and a steam superheater 23 of the tertiary heating section and the electric loads of a primary heating geothermal subsystem. The heat load of the secondary heating section is for example entirely replaced by three heats, the sixth control valve 34 is adjusted, and the seventh control valve 35 closes the passage of steam to the first steam generator 4. The steam production process is, for example: the water storage tank 17 is pressurized by a water feeding pump 18, then passes through a preheater 7, a first condenser 11, a second condenser 15, a steam generator 22 and a steam superheater 23 in sequence to become superheated steam, and finally is injected into the well.

In summary, the embodiment of the present disclosure provides a heavy oil thermal recovery steam injection system based on multi-energy complementation, which includes subsystems with multiple energy sources. Through the tight connection among the subsystems, an energy cascade utilization method can be adopted, the electric energy generated by the wind energy subsystem is combined with different grade heat energy provided by the solar subsystem and the geothermal subsystem, the energy grade of geothermal energy is improved by utilizing the electric energy, and the electric energy is used as a heat source for supplementing heating of the geothermal subsystem. The high-temperature heat energy generated or stored by the solar subsystem is used as intermediate-grade heat energy to provide heat energy for heating in the intermediate-temperature section, and finally the electric energy generated by the wind energy subsystem is used as high-grade energy to be provided for the high-temperature steam heating/overheating section in the steam production subsystem, so that the cascade comprehensive utilization of different qualities of energy is realized.

It should be understood that the specific order or hierarchy of steps in the processes disclosed is an example of exemplary approaches. Based upon design preferences, it is understood that the specific order or hierarchy of steps in the processes may be rearranged without departing from the scope of the present disclosure. The accompanying method claims present elements of the various steps in a sample order, and are not intended to be limited to the specific order or hierarchy.

It should also be noted that directional terms, such as "upper", "lower", "front", "rear", "left", "right", etc., mentioned in the embodiments are only directions referring to the drawings, and are not intended to limit the scope of the present disclosure. Throughout the drawings, like elements are represented by like or similar reference numerals. Conventional structures or constructions will be omitted when they may obscure the understanding of the present disclosure. And the shapes, sizes and positional relationships of the components in the drawings do not reflect the actual sizes, proportions and actual positional relationships.

In the foregoing detailed description, various features are grouped together in a single embodiment for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments of the subject matter require more features than are expressly recited in each claim. Rather, as the following claims reflect, the disclosure may lie in less than all features of a single disclosed embodiment. Thus, the following claims are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the disclosure.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present disclosure, "a plurality" means at least two, e.g., two, three, etc., unless explicitly specifically limited otherwise. To the extent that the term "includes" is used in either the detailed description or the claims, such term is intended to be inclusive in a manner similar to the term "comprising" as "comprising" is interpreted when employed as a transitional word in a claim. Any use of the term "or" in the specification of the claims is intended to mean a "non-exclusive or".

The above-mentioned embodiments are intended to illustrate the objects, aspects and advantages of the present disclosure in further detail, and it should be understood that the above-mentioned embodiments are only illustrative of the present disclosure and are not intended to limit the present disclosure, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present disclosure should be included in the scope of the present disclosure.

Claims

1. A thickened oil thermal recovery steam injection system based on multi-energy complementation is characterized by comprising:

a geothermal subsystem, a solar subsystem, a wind energy subsystem and a steam production subsystem;

the geothermal subsystem comprises a primary heat pump and a secondary heat pump, the steam production subsystem comprises a first steam generator (4) and a steam heat exchanger, the geothermal subsystem is in heat exchange connection with the steam production subsystem through the primary heat pump and is used for carrying out primary heating on softened water, the solar subsystem is in heat exchange connection with the first steam generator (4) and is used for carrying out secondary heating on the softened water, and the wind energy subsystem is electrically connected with the steam heat exchanger and is used for carrying out tertiary heating on the softened water;

the geothermal subsystem is in heat exchange connection with the solar subsystem through the secondary heat pump;

the wind energy subsystem is also electrically connected with the primary heat pump and the secondary heat pump respectively;

the geothermal subsystem, the solar subsystem and the wind energy subsystem respectively generate geothermal energy, first energy and second energy; the energy quality of the geothermal energy source, the energy quality of the first energy source and the energy quality of the second energy source are sequentially increased, and the steam production subsystem is used for comprehensively and stepwisely utilizing the geothermal energy source, the energy quality of the first energy source and the energy quality of the second energy source to heat softened water in a segmented mode to produce steam.

2. The heavy oil thermal recovery steam injection system based on multi-energy complementation according to claim 1, wherein the geothermal subsystem further comprises:

an underground mining device (6) and a three-stage heat pump;

wherein the underground mining device (6) is used for mining the geothermal energy source and inputting the geothermal energy source into the three-stage heat pump;

the primary heat pump comprises a first condenser (11), a secondary evaporator (8), a first compressor (10) and a first throttle valve (12);

the secondary evaporator (8) is in heat exchange connection with the tertiary heat pump and used for absorbing heat energy of geothermal energy and using the heat energy for evaporation of a heat pump cycle fluid, the geothermal subsystem is in heat exchange connection with the steam production subsystem through the first condenser (11), the first compressor (10) is electrically connected with the wind energy subsystem and used for improving pressure of the heat pump cycle fluid, energy quality of the geothermal energy is improved by using the second energy to obtain first mixed energy, and the first throttle valve (12) is used for reducing pressure of the heat pump cycle fluid output by the first condenser (11).

3. The heavy oil thermal recovery steam injection system based on multi-energy complementation as recited in claim 2, characterized in that the steam production subsystem further comprises a preheater (7), and the three-stage heat pump is further connected with the preheater (7) in a heat exchange manner.

4. The heavy oil thermal recovery steam injection system based on multi-energy complementation according to claim 2, wherein the secondary heat pump comprises:

a second evaporator (13), a second compressor (14), a second condenser (15) and a second throttle valve (16);

the second evaporator (13) is in heat exchange connection with the primary heat pump and is used for absorbing heat energy of the first mixed energy and using the heat energy for evaporation of a circulating working medium of the secondary heat pump, the second compressor (14) is electrically connected with the wind energy subsystem and is used for improving pressure of the circulating working medium of the heat pump, energy quality of the first mixed energy is improved by using the second energy to obtain second mixed energy, the second condenser (15) is in heat exchange connection with the solar energy subsystem and is used for storing the second mixed energy to the solar energy subsystem, and the second throttle valve (16) is used for reducing pressure of the circulating working medium of the heat pump output by the second condenser (15);

the second condenser (15) is also in heat exchange connection with the steam heat exchanger.

5. The heavy oil thermal recovery steam injection system based on multi-energy complementation according to claim 4, wherein the solar subsystem comprises:

a solar heat collector (1) and a heat storage device;

the solar energy heat collector (1), the heat storage device and the first steam generator (4) are connected with each other through a tee joint, the second condenser (15) is in heat exchange connection with the heat storage device, and the heat storage device is used for storing, releasing and absorbing high-temperature working media behind the geothermal energy, the first energy and the second energy and low-temperature working media behind the heat exchange.

6. The heavy oil thermal recovery steam injection system based on multi-energy complementation, according to claim 5, wherein the heat storage device comprises:

a high-temperature storage tank (2) and a low-temperature storage tank (3);

and the heat pump circulating working medium flows out of the low-temperature storage tank (3), exchanges heat with the second condenser (15), and flows into the high-temperature storage tank (2).

7. The heavy oil thermal recovery steam injection system based on multi-energy complementation according to claim 1, wherein the wind energy subsystem comprises:

the wind power generation system comprises a wind generating set (19), an electric control device (20) and a control center (25);

the wind generating set (19) is electrically connected with the electric control device (20), the steam heat exchanger, the primary heat pump and the secondary heat pump respectively;

the electric control device (20) is in communication connection with the control center (25) and is used for controlling the second energy source to heat softened water for three times, improving the energy quality of the geothermal energy source and connecting an external power grid (21).

8. The heavy oil thermal recovery steam injection system based on multi-energy complementation according to claim 2, wherein the geothermal subsystem further comprises a produced water supply device (S2);

the primary heat pump further comprises a primary evaporator (9), the primary evaporator (9) is in heat exchange connection with the oil extraction sewage water supply device (S2) and used for absorbing the waste heat of the oil extraction sewage, the energy quality of the waste heat of the oil extraction sewage is improved by the aid of the second energy in circulation of the primary heat pump, and the first mixed energy is obtained.

9. The heavy oil thermal recovery steam injection system based on multi-energy complementation according to claim 1, wherein the steam heat exchanger comprises:

a second steam generator (22) and a steam superheater (23);

the steam production subsystem further comprises:

a control valve;

wherein the second steam generator (22) and the steam superheater (23) are used for heating softened water for three times by using the second energy source, and the control valve is used for controlling the geothermal energy source, the utilization ratio of the first energy source and the second energy source and the generated steam flow.