Offshore crude oil treatment device and method

Abstract

The invention discloses an offshore crude oil treatment device and method, the device comprises a primary separator, a heat pump device and a secondary separator, the primary separator is provided with an initial crude oil inlet and a low-temperature crude oil intermediate product outlet; the heat pump device comprises a condenser, a low-temperature crude oil intermediate product inlet and a high-temperature crude oil intermediate product outlet are formed in the condenser, and the low-temperature crude oil intermediate product outlet of the primary separator is communicated with the low-temperature crude oil intermediate product inlet of the condenser through a pipeline; the secondary separator is provided with a high-temperature crude oil intermediate product inlet; and the high-temperature crude oil intermediate product outlet of the condenser is communicated with the high-temperature crude oil intermediate product inlet of the secondary separator through a pipeline. The heat pump device replaces an electric heater to be applied to offshore crude oil treatment, electricity consumption is basically not needed, electricity consumption is reduced, compared with an existing electric heater, heating and energy efficiency is higher, and the problem that current offshore crude oil treatment is high in electricity consumption is solved.

Description

Technical Field

[0001] The present invention relates to the field of waste heat utilization in offshore oil and gas fields, and in particular to an offshore crude oil processing device and method. Background Art

[0002] Crude oil produced from offshore oil fields usually contains water, associated gas and solid impurities, and needs to go through a processing process to improve the quality and production efficiency of the crude oil, including crude oil separation and dehydration. An oil-gas-water three-phase separator is used for the initial separation of crude oil. In order to achieve a better separation effect, electric heaters are usually used to reduce the viscosity of the crude oil and accelerate the sedimentation of water droplets. The design is integrated into an "separation-heating-re-separation" design to reduce the footprint of offshore platforms. However, electric heaters consume a lot of power, and the separated high-temperature production water is directly discharged into the sea, which not only wastes heat, but also affects the growth of phytoplankton and zooplankton, affecting the marine ecological environment. The offshore crude oil processing process is the core link in offshore oil and gas development. How to strike a balance between efficiency, safety and environmental protection is the technical direction for achieving green, low-carbon and economic development of offshore platforms.

[0003] In short, the current offshore crude oil processing process uses electric heaters to heat the crude oil to dehydrate and reduce its viscosity. The high-temperature water generated is directly discharged into the sea, resulting in high power consumption and waste of low-grade heat sources. Summary of the Invention

[0004] In response to the above problems, the present invention aims to provide an offshore crude oil processing device and method to solve the current offshore crude oil processing process that uses electric heaters to heat the crude oil to dehydrate and reduce its viscosity. The resulting high-temperature water is directly discharged into the sea, resulting in high power consumption and waste of low-grade heat sources.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] In a first aspect, the present invention discloses an offshore crude oil processing device, comprising

[0007] A first-stage separator is provided with an initial crude oil inlet and a low-temperature crude oil intermediate product outlet;

[0008] The heat pump device includes a condenser, wherein the condenser is provided with a low-temperature crude oil intermediate product inlet and a high-temperature crude oil intermediate product outlet, and the low-temperature crude oil intermediate product outlet of the primary separator is connected to the low-temperature crude oil intermediate product inlet of the condenser through a pipeline;

[0009] a secondary separator provided with a high-temperature crude oil intermediate product inlet and a target crude oil outlet, wherein the high-temperature crude oil intermediate product outlet of the condenser is connected to the high-temperature crude oil intermediate product inlet of the secondary separator via a pipeline;

[0010] Wherein, the initial crude oil import is used to receive the initial crude oil;

[0011] The initial crude oil is separated and processed in a primary separator to produce a low-temperature crude oil intermediate product;

[0012] The low-temperature crude oil intermediate product is converted into a high-temperature crude oil intermediate product through heat exchange in a heat pump device;

[0013] The high-temperature crude oil intermediate product is separated and processed in a secondary separator to generate the target crude oil;

[0014] The target crude oil outlet is used to discharge the target crude oil.

[0015] Preferably, the heat pump device further comprises a compressor, an expansion valve and an evaporator, wherein the compressor, the condenser, the expansion valve and the evaporator each comprise a refrigerant inlet and an outlet, and the refrigerant inlets and outlets of the compressor, the condenser, the expansion valve and the evaporator are connected end to end in sequence to form a refrigerant circulation loop;

[0016] Among them, the high-temperature crude oil intermediate product will also produce high-temperature water after separation and treatment in the secondary separator;

[0017] The secondary separator is also provided with a high-temperature water outlet, and the evaporator is also provided with a high-temperature water inlet and a low-temperature water outlet for discharging into the sea, and the low-temperature water outlet for discharging into the sea is connected to the high-temperature water inlet, and the high-temperature water outlet of the secondary separator is connected to the high-temperature water inlet of the evaporator through a pipeline;

[0018] When the high-temperature water flowing out of the high-temperature water outlet of the secondary separator passes through the evaporator, it transfers heat to the refrigerant in the evaporator and turns into low-temperature water, which is discharged through the low-temperature water outlet.

[0019] Preferably, the refrigerant inlet and outlet of the compressor are respectively a high-temperature, low-pressure gaseous refrigerant inlet and a high-temperature, high-pressure gaseous refrigerant outlet;

[0020] The refrigerant inlet and outlet of the condenser are respectively a high-temperature and high-pressure gaseous refrigerant inlet and a low-temperature and high-pressure liquid refrigerant outlet.

[0021] The refrigerant inlet and outlet of the expansion valve are respectively a low-temperature and high-pressure liquid refrigerant inlet and a low-temperature and low-pressure liquid refrigerant outlet.

[0022] The refrigerant inlet and outlet of the evaporator are respectively a low-temperature and low-pressure liquid refrigerant inlet and a high-temperature and low-pressure gaseous refrigerant outlet.

[0023] The high-temperature and high-pressure gaseous refrigerant outlet of the compressor is connected to the high-temperature and high-pressure gaseous refrigerant inlet of the condenser through a pipeline, the low-temperature and high-pressure liquid refrigerant outlet of the condenser is connected to the low-temperature and high-pressure liquid refrigerant inlet of the expansion valve through a pipeline, the low-temperature and low-pressure liquid refrigerant outlet of the expansion valve is connected to the low-temperature and low-pressure liquid refrigerant inlet of the evaporator through a pipeline, and the high-temperature and low-pressure gaseous refrigerant outlet of the evaporator is connected to the high-temperature and low-pressure gaseous refrigerant inlet of the compressor through a pipeline, thereby forming a refrigerant circulation loop;

[0024] The compressor is used to compress the high-temperature, low-pressure gaseous refrigerant into a high-temperature, high-pressure gaseous refrigerant.

[0025] The condenser is used to transfer the heat of the high-temperature and high-pressure gaseous refrigerant to the intermediate product of crude oil, so that the high-temperature and high-pressure gaseous refrigerant is cooled and condensed into a liquid state, becoming a low-temperature and high-pressure liquid refrigerant, and at the same time releases heat to heat the intermediate product of crude oil, so that the low-temperature intermediate product of crude oil is heated and turned into a high-temperature intermediate product of crude oil;

[0026] The expansion valve is used to throttle and reduce the pressure of the low-temperature and high-pressure liquid refrigerant, returning it to a low-temperature and low-pressure state, and turning it into a low-temperature and low-pressure liquid refrigerant;

[0027] The evaporator is used to absorb the heat released when high-temperature water passes through the evaporator to heat the low-temperature, low-pressure liquid refrigerant, so that the low-temperature, low-pressure liquid refrigerant is converted into a high-temperature, low-pressure gaseous refrigerant, and at the same time the temperature of the high-temperature water is reduced to low-temperature water.

[0028] Preferably, the primary separator is an oil-water two-phase separator, which is also provided with a free water outlet.

[0029] The free water outlet is used to discharge free water generated when the initial crude oil is separated and processed by the primary separator.

[0030] Preferably, the secondary separator is an oil-gas-water three-phase separator, which is also provided with a gas outlet.

[0031] The gas outlet is used to discharge the gas released when the high-temperature crude oil intermediate product is separated and processed by the secondary separator.

[0032] In a second aspect, the present invention also discloses a method for processing offshore crude oil, which uses the above-mentioned offshore crude oil processing device, comprising:

[0033] The initial crude oil enters the primary separator through the initial crude oil inlet of the primary separator;

[0034] The first-stage separator performs preliminary separation on the initial crude oil, removes some free water, and generates low-temperature crude oil intermediates;

[0035] The low-temperature crude oil intermediate product flows out from the low-temperature crude oil intermediate product outlet and enters the condenser through the low-temperature crude oil intermediate product inlet of the condenser;

[0036] The condenser transfers the heat of the refrigerant to the intermediate product of crude oil to increase the temperature of the intermediate product of crude oil, thereby increasing the temperature of the low-temperature intermediate product of crude oil to become a high-temperature intermediate product of crude oil;

[0037] The high-temperature crude oil intermediate product flows out from the high-temperature crude oil intermediate product outlet of the condenser and enters the secondary separator through the high-temperature crude oil intermediate product inlet of the secondary separator;

[0038] The secondary separator separates the high-temperature crude oil intermediate product to generate liquid target crude oil, which flows out through the target crude oil outlet.

[0039] Preferably, while the secondary separator is performing a three-phase separation process on the high-temperature crude oil intermediate product, the refrigerant is circulated in the refrigerant circulation loop, and the circulation steps are as follows:

[0040] The high-temperature, low-pressure gaseous refrigerant enters the compressor and is compressed into a high-temperature, high-pressure gaseous refrigerant by the compressor;

[0041] The high-temperature and high-pressure gas refrigerant enters the condenser, which transfers the heat of the refrigerant to the intermediate product of crude oil, cooling and condensing the high-temperature and high-pressure gas refrigerant into liquid, turning it into low-temperature and high-pressure liquid refrigerant. At the same time, the heat is released to heat the intermediate product of crude oil, causing the low-temperature intermediate product of crude oil to heat up and turn into high-temperature intermediate product of crude oil.

[0042] The low-temperature and high-pressure liquid refrigerant passes through the expansion valve to throttle and reduce the pressure, returning to a low-temperature and low-pressure state, and becomes a low-temperature and low-pressure liquid refrigerant;

[0043] The low-temperature, low-pressure liquid refrigerant enters the evaporator and exchanges heat with the high-temperature water produced by separating the high-temperature crude oil intermediate products in the secondary separator. The low-temperature, low-pressure liquid refrigerant absorbs heat and evaporates into gas, becoming a high-temperature, low-pressure gaseous refrigerant. The high-temperature, high-pressure gas refrigerant re-enters the compressor, forming a refrigerant circulation in the heat pump device.

[0044] Preferably, when the primary separator performs preliminary separation treatment on the initial crude oil, the separated free water flows out from the free water outlet;

[0045] When the secondary separator separates the high-temperature crude oil intermediate product, gas is also released and high-temperature water is generated. The released gas flows out through the released gas outlet, and the high-temperature water flows out through the high-temperature water outlet.

[0046] Preferably, during the circulation of the refrigerant in the refrigerant circulation loop, the condenser simultaneously receives the high-temperature and high-pressure refrigerant and the low-temperature crude oil intermediate product flowing out from the low-temperature crude oil intermediate product outlet of the first-level separator. The low-temperature crude oil intermediate product exchanges heat with the high-temperature and high-pressure refrigerant in the condenser, and the low-temperature crude oil intermediate product becomes a high-temperature crude oil intermediate product, while the high-temperature and high-pressure refrigerant becomes a low-temperature and high-pressure refrigerant.

[0047] Preferably, during the circulation of the refrigerant in the refrigerant circulation loop, the evaporator simultaneously receives high-temperature water and low-temperature, low-pressure liquid refrigerant flowing out from the high-temperature water outlet of the secondary separator, the low-temperature, low-pressure liquid refrigerant exchanges heat with the high-temperature water, the low-temperature, low-pressure liquid refrigerant becomes a high-temperature, low-pressure gaseous refrigerant, and at the same time the temperature of the high-temperature water is reduced to become low-temperature water, which flows out from the low-temperature water discharge outlet of the evaporator and is discharged into the sea.

[0048] Compared with the prior art, the present invention has the following beneficial effects:

[0049] (1) The present invention discloses an offshore crude oil processing device, comprising a primary separator, a heat pump device, and a secondary separator, wherein the primary separator is provided with an initial crude oil inlet and a low-temperature crude oil intermediate product outlet; the heat pump device comprises a condenser, wherein the condenser is provided with a low-temperature crude oil intermediate product inlet and a high-temperature crude oil intermediate product outlet, the low-temperature crude oil intermediate product outlet of the primary separator being connected to the low-temperature crude oil intermediate product inlet of the condenser via a pipeline; and the secondary separator is provided with a high-temperature crude oil intermediate product inlet and a target crude oil outlet, the high-temperature crude oil intermediate product outlet of the condenser being connected to the high-temperature crude oil intermediate product inlet of the secondary separator via a pipeline. During the refrigerant circulation in the refrigerant circulation loop, the condenser simultaneously receives high-temperature and high-pressure refrigerant and the low-temperature crude oil intermediate product flowing out of the low-temperature crude oil intermediate product outlet of the primary separator, the low-temperature crude oil intermediate product undergoes heat exchange with the high-temperature and high-pressure refrigerant in the condenser, and the low-temperature crude oil intermediate product becomes a high-temperature crude oil intermediate product, while the high-temperature and high-pressure refrigerant becomes a low-temperature and high-pressure refrigerant. The present invention discloses an offshore crude oil processing device that uses a heat pump device instead of an electric heater for offshore crude oil processing. This device requires virtually no electricity, thus reducing power consumption and achieving higher energy efficiency than current electric heater heating. This device solves the current problem of high power consumption in offshore crude oil processing, which involves using crude oil to heat the crude oil for dehydration and viscosity reduction.

[0050] (2) The present invention discloses a method for processing offshore crude oil. During the refrigerant circulation process in the refrigerant circulation loop, the evaporator simultaneously receives high-temperature water and low-temperature, low-pressure liquid refrigerant flowing out of the high-temperature water outlet of the secondary separator. The low-temperature, low-pressure liquid refrigerant exchanges heat with the high-temperature water, and the low-temperature, low-pressure liquid refrigerant becomes a high-temperature, low-pressure gaseous refrigerant. At the same time, the temperature of the high-temperature water decreases and becomes low-temperature water. The low-temperature water flows out of the low-temperature water discharge outlet of the evaporator and is discharged into the sea. The present invention discloses a method for processing offshore crude oil. The crude oil is heated by recycling the waste heat of the generated high-temperature water. This is not only to achieve the utilization of low-grade heat sources, but also more energy-saving and environmentally friendly. It also reduces the discharge temperature of the produced water into the sea, alleviating the impact of the high-temperature water discharge into the sea on the marine ecological environment.

[0051] (3) The present invention discloses an offshore crude oil processing method, which aims at energy-saving optimization of offshore crude oil processing technology. By applying the waste heat removed from the produced water during the crude oil processing process to heat pump technology, the discharge temperature into the sea is reduced, and the heat waste caused by directly discharging high-temperature produced water into the sea and affecting the marine ecological environment is reduced. It shows good application prospects in the energy-saving transformation plan of offshore crude oil processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 A schematic structural diagram of an offshore crude oil processing unit provided in Example 1 of the present invention;

[0053] Figure 2 This is a schematic diagram of the internal structure of the heat pump device provided in Example 1 of the present invention.

[0054] Description of reference numerals:

[0055] 1-primary separator, 10-initial crude oil inlet, 11-low-temperature crude oil intermediate product outlet, 12-free water outlet;

[0056] 2-heat pump device, 20-compressor, 21-condenser, 22-expansion valve, 23-evaporator, 230-low-temperature water discharge outlet;

[0057] 3-secondary separator, 31-high-temperature crude oil intermediate product inlet, 32-target crude oil outlet, 33-high-temperature water outlet, 34-extracted gas outlet. DETAILED DESCRIPTION

[0058] Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. Rather, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0059] Heat pumps do not generate heat directly through electricity or fuel. Instead, they absorb low-grade heat energy from the environment through the phase change cycle of the refrigerant, compress it to increase the temperature, and then release it to the target area. It has a higher energy efficiency ratio and is more energy-efficient than electric heaters. The main components of a heat pump include an evaporator 23, a compressor 20, a condenser 21, and an expansion valve 22. Heat transfer is achieved through four steps: evaporation, compression, condensation, and expansion. Most of the previous patents involving crude oil processing processes focused on crude oil dehydration and separation devices, and did not introduce heat pumps into the high-temperature production water waste heat recovery and crude oil reheating processes in the crude oil separation process. Heat pumps have the advantages of high efficiency, energy saving, and environmental protection, improving the overall energy efficiency of the system and providing a green, low-carbon, and safe solution for offshore crude oil processing.

[0060] The present invention discloses an offshore crude oil processing device that uses a heat pump device instead of an electric heater for offshore crude oil processing. This device requires virtually no electricity, thus reducing power consumption and achieving higher energy efficiency than current electric heater heating. This device solves the current problem of high power consumption in offshore crude oil processing, which involves using crude oil to heat the crude oil for dehydration and viscosity reduction.

[0061] Example 1: An offshore crude oil processing device

[0062] Embodiment 1 of the present invention provides an offshore crude oil processing device, and its structure is described in detail below with reference to the accompanying drawings.

[0063] refer to Figure 1 The offshore crude oil processing device includes a primary separator 1, a heat pump device 2 and a secondary separator 3.

[0064] The primary separator 1 is provided with an initial crude oil inlet 10 , a low-temperature crude oil intermediate product outlet 11 and a free water outlet 12 .

[0065] The heat pump device 2 includes a condenser 21, an expansion valve 22, an evaporator 23 and a compressor 20. The condenser 21, the expansion valve 22, the evaporator 23 and the compressor 20 all include a refrigerant inlet and an outlet. The refrigerant inlets and outlets of the condenser 21, the expansion valve 22, the evaporator 23 and the compressor 20 are connected end to end in sequence to form a refrigerant circulation loop.

[0066] The secondary separator 3 is an oil, gas and water three-phase separator, which is provided with a high-temperature crude oil intermediate product inlet 31 and a target crude oil outlet 32 .

[0067] The condenser 21 is also provided with a low-temperature crude oil intermediate product inlet and a high-temperature crude oil intermediate product outlet. The low-temperature crude oil intermediate product outlet 11 of the primary separator 1 is connected to the low-temperature crude oil intermediate product inlet of the condenser 21 via a pipeline, and the high-temperature crude oil intermediate product outlet of the condenser 21 is connected to the high-temperature crude oil intermediate product inlet 31 of the secondary separator 3 via a pipeline.

[0068] Among them, the initial crude oil import 10 is used to receive the initial crude oil;

[0069] The initial crude oil is separated and processed in the first-stage separator 1 to produce a low-temperature crude oil intermediate product;

[0070] The low-temperature crude oil intermediate product is converted into a high-temperature crude oil intermediate product through heat exchange by the heat pump device 2;

[0071] The high-temperature crude oil intermediate product is separated and processed in the secondary separator 3 to produce the target crude oil;

[0072] The target crude oil outlet 32 is used to discharge the target crude oil.

[0073] The oil-gas-water three-phase separator uses gravity settling, fluid dynamics, and interphase control to efficiently separate oil, gas, and water from mixed fluids. Efficiency is improved through structural optimization, such as the gravity settling zone, coalescing elements, and control of parameters such as pressure, temperature, and residence time.

[0074] The heat pump device 2 is based on a reverse Carnot cycle and transfers heat from a low-temperature heat source to a high-temperature heat source by consuming mechanical energy.

[0075] refer to Figure 2 The heat pump device 2 also includes a compressor 20, an expansion valve 22 and an evaporator 23. The compressor 20, the condenser 21, the expansion valve 22 and the evaporator 23 all include a refrigerant inlet and an outlet. The refrigerant inlets and outlets of the compressor 20, the condenser 21, the expansion valve 22 and the evaporator 23 are connected end to end in sequence to form a refrigerant circulation loop.

[0076] Among them, the high-temperature crude oil intermediate product will also produce high-temperature water after being separated and processed by the secondary separator 3.

[0077] In order to discharge the generated high-temperature water, a high-temperature water outlet 33 is further provided on the secondary separator 3 .

[0078] In order to use the generated high-temperature water as a heat source in the evaporator 23 of the heat pump device 2, to promote the evaporation of the low-temperature and low-pressure liquid refrigerant into a gaseous state, and to facilitate the discharge of the high-temperature water into the sea after the temperature is reduced, a high-temperature water inlet and a low-temperature water sea outlet 230 are also provided on the evaporator 23, and the low-temperature water sea outlet 230 is connected to the high-temperature water inlet, and the high-temperature water outlet 33 of the secondary separator 3 is connected to the high-temperature water inlet of the evaporator 23 through a pipeline.

[0079] When the high-temperature water flowing out of the high-temperature water outlet 33 of the secondary separator 3 passes through the evaporator 23 , it transfers heat to the refrigerant in the evaporator 23 and turns into low-temperature water, which is then discharged through the low-temperature water outlet 230 .

[0080] The heat pump device 2 is a conventional technology, which includes a cycle of evaporation, compression, condensation and throttling. Its basic working principle is as follows:

[0081] During the evaporation of the refrigerant in the evaporator 23, the low-temperature, low-pressure liquid refrigerant absorbs heat from the high-temperature produced water in the evaporator 23 and evaporates into a gaseous state, becoming a high-temperature, low-pressure gaseous refrigerant.

[0082] During the process of the refrigerant being compressed by the compressor 20 , the pressure of the high-temperature, low-pressure gaseous refrigerant increases, and the temperature rises, turning it into a high-temperature, high-pressure gaseous refrigerant.

[0083] During the condensation of the refrigerant in the condenser 21, the high-temperature and high-pressure gaseous refrigerant releases heat to the low-temperature crude oil intermediate product in the condenser 21, the temperature drops, and the gaseous refrigerant condenses into liquid, becoming a low-temperature and high-pressure liquid refrigerant, while releasing a large amount of latent heat.

[0084] During the throttling process of the refrigerant in the expansion valve 22, the condensed low-temperature and high-pressure liquid refrigerant is throttled and reduced in pressure through the expansion valve 22, returns to a low-temperature and low-pressure state, and becomes a low-temperature and low-pressure liquid refrigerant. The low-temperature and low-pressure liquid refrigerant re-enters the evaporator 23, forming a refrigerant circulation process.

[0085] Since the heat pump device 2 is a prior art, the above working principle is common knowledge and will not be described in detail here.

[0086] As a specific embodiment, the refrigerant inlet and outlet of the compressor 20 are respectively a high-temperature, low-pressure gaseous refrigerant inlet and a high-temperature, high-pressure gaseous refrigerant outlet;

[0087] The refrigerant inlet and outlet of the condenser 21 are respectively a high-temperature and high-pressure gaseous refrigerant inlet and a low-temperature and high-pressure liquid refrigerant outlet.

[0088] The refrigerant inlet and outlet of the expansion valve 22 are respectively a low-temperature and high-pressure liquid refrigerant inlet and a low-temperature and low-pressure liquid refrigerant outlet.

[0089] The refrigerant inlet and outlet of the evaporator 23 are respectively a low-temperature and low-pressure liquid refrigerant inlet and a high-temperature and low-pressure gaseous refrigerant outlet.

[0090] The high-temperature and high-pressure gaseous refrigerant outlet of the compressor 20 is connected to the high-temperature and high-pressure gaseous refrigerant inlet of the condenser 21 through a pipeline, the low-temperature and high-pressure liquid refrigerant outlet of the condenser 21 is connected to the low-temperature and high-pressure liquid refrigerant inlet of the expansion valve 22 through a pipeline, the low-temperature and low-pressure liquid refrigerant outlet of the expansion valve 22 is connected to the low-temperature and low-pressure liquid refrigerant inlet of the evaporator 23 through a pipeline, and the high-temperature and low-pressure gaseous refrigerant outlet of the evaporator 23 is connected to the high-temperature and low-pressure gaseous refrigerant inlet of the compressor 20 through a pipeline, thereby forming a refrigerant circulation loop;

[0091] The compressor 20 is used to compress the high-temperature, low-pressure gaseous refrigerant into a high-temperature, high-pressure gaseous refrigerant.

[0092] The condenser 21 is used to transfer the heat of the high-temperature and high-pressure gaseous refrigerant to the intermediate product of crude oil. The high-temperature and high-pressure gaseous refrigerant is cooled and condensed into a liquid state, becoming a low-temperature and high-pressure liquid refrigerant. At the same time, the heat is released to heat the intermediate product of crude oil, causing the low-temperature intermediate product of crude oil to heat up and become a high-temperature intermediate product of crude oil.

[0093] The expansion valve 22 is used to throttle and reduce the pressure of the low-temperature and high-pressure liquid refrigerant, returning it to a low-temperature and low-pressure state, and turning it into a low-temperature and low-pressure liquid refrigerant;

[0094] The evaporator 23 is used to absorb the heat released when the high-temperature water passes through the evaporator 23 to heat the low-temperature, low-pressure liquid refrigerant, so that the low-temperature, low-pressure liquid refrigerant is converted into a high-temperature, low-pressure gaseous refrigerant. At the same time, the temperature of the high-temperature water is reduced to low-temperature water.

[0095] Specifically, the primary separator 1 is an oil-water two-phase separator, and is further provided with a free water outlet 12 . The free water outlet 12 is used to discharge free water generated when the initial crude oil is separated and processed by the primary separator 1 .

[0096] Specifically, the secondary separator 3 is an oil-gas-water three-phase separator. In addition to a high-temperature intermediate crude oil product inlet 31, a target crude oil outlet 32, and a high-temperature water outlet 33, it is also provided with a gas outlet 34. The gas outlet 34 is used to discharge the gas released during the separation and treatment of the high-temperature intermediate crude oil product by the secondary separator 3.

[0097] Example 2: A method for processing offshore crude oil

[0098] Embodiment 2 of the present invention provides an offshore crude oil processing method, using the offshore crude oil processing device of embodiment 1, the method comprising the following steps:

[0099] Step S1: initial crude oil enters the primary separator 1 through the initial crude oil inlet 10 of the primary separator 1;

[0100] Step S2: The primary separator 1 performs a preliminary separation treatment on the initial crude oil to remove some free water and generate a low-temperature crude oil intermediate product. The free water flows out from the free water outlet 12, and the low-temperature crude oil intermediate product flows out from the low-temperature crude oil intermediate product outlet 11 and enters the condenser 21 through the low-temperature crude oil intermediate product inlet of the condenser 21.

[0101] Step S3: The condenser 21 transfers the heat of the refrigerant to the intermediate product of crude oil, and the high-temperature and high-pressure refrigerant is cooled to become low-temperature and high-pressure refrigerant. At the same time, the heat is released to heat the intermediate product of crude oil, and the low-temperature intermediate product of crude oil is heated to become high-temperature intermediate product of crude oil.

[0102] Step S4: The high-temperature crude oil intermediate product flows out from the high-temperature crude oil intermediate product outlet of the condenser 21 and enters the secondary separator 3 through the high-temperature crude oil intermediate product inlet 31 of the secondary separator 3;

[0103] Step S5: The secondary separator 3 performs a three-phase separation process on the high-temperature crude oil intermediate product to generate liquid target crude oil, degassing gas, and high-temperature water, respectively. The target crude oil flows out through the target crude oil outlet 32 and enters the subsequent gas treatment process or is exported. The degassing gas flows out through the degassing gas outlet 34, and the high-temperature water flows out through the high-temperature water outlet 33 and enters the evaporator 23 in the heat pump device.

[0104] While the secondary separator 3 is performing a three-phase separation process on the high-temperature crude oil intermediate product, the refrigerant circulates in the refrigerant circulation loop. The circulation steps are as follows:

[0105] The high-temperature, low-pressure gaseous refrigerant enters the compressor 20 and is compressed by the compressor 20 into a high-temperature, high-pressure gaseous refrigerant;

[0106] The high-temperature and high-pressure gas refrigerant enters the condenser 21. The condenser 21 transfers the heat of the refrigerant to the crude oil intermediate product, cooling and condensing the high-temperature and high-pressure gas refrigerant into a liquid state, turning it into a low-temperature and high-pressure liquid refrigerant. At the same time, the heat is released to heat the crude oil intermediate product, causing the low-temperature crude oil intermediate product to heat up and turn into a high-temperature crude oil intermediate product.

[0107] The low-temperature, high-pressure liquid refrigerant passes through the expansion valve 22 and is throttled and depressurized, returning to a low-temperature, low-pressure state, becoming a low-temperature, low-pressure liquid refrigerant.

[0108] The low-temperature, low-pressure liquid refrigerant enters the evaporator 23 and exchanges heat with the high-temperature water produced by separating the high-temperature crude oil intermediate product in the secondary separator 3. The low-temperature, low-pressure liquid refrigerant absorbs heat and evaporates into a gaseous state, becoming a high-temperature, low-pressure gaseous refrigerant. The high-temperature, high-pressure gaseous refrigerant re-enters the compressor 20, forming a refrigerant circulation in the heat pump device 2.

[0109] The generated high-temperature water serves as a heat source in the heat pump evaporator 23, causing the low-temperature and low-pressure liquid refrigerant to evaporate into a gaseous state, thereby becoming a high-temperature and high-pressure gas refrigerant.

[0110] Specifically, when the primary separator 1 performs preliminary separation processing on the initial crude oil, the separated free water flows out from the free water outlet 12 .

[0111] Specifically, when the secondary separator 3 separates and processes the high-temperature crude oil intermediate product, gas is also released and high-temperature water is generated. The released gas flows out through the released gas outlet 34 , and the high-temperature water flows out through the high-temperature water outlet 33 .

[0112] During the circulation of the refrigerant in the refrigerant circulation loop, the condenser 21 simultaneously receives the high-temperature and high-pressure refrigerant and the low-temperature crude oil intermediate product flowing out of the low-temperature crude oil intermediate product outlet 11 of the first-stage separator 1. The low-temperature crude oil intermediate product exchanges heat with the high-temperature and high-pressure refrigerant in the condenser 21, and the low-temperature crude oil intermediate product becomes a high-temperature crude oil intermediate product, while the high-temperature and high-pressure refrigerant becomes a low-temperature and high-pressure refrigerant.

[0113] During the circulation of the refrigerant in the refrigerant circulation loop, the evaporator 23 simultaneously receives high-temperature water and low-temperature, low-pressure liquid refrigerant flowing out from the high-temperature water outlet 33 of the secondary separator 3. The low-temperature, low-pressure liquid refrigerant exchanges heat with the high-temperature water, and the low-temperature, low-pressure liquid refrigerant becomes a high-temperature, low-pressure gaseous refrigerant. At the same time, the temperature of the high-temperature water decreases and becomes low-temperature water. The low-temperature water flows out from the low-temperature water sea outlet 230 of the evaporator 23 and is discharged into the sea.

[0114] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. An offshore crude oil processing unit, characterized in that: include A primary separator (1) is provided with an initial crude oil inlet (10) and a low-temperature crude oil intermediate product outlet (11); The heat pump device (2) includes a condenser (21), wherein the condenser (21) is provided with a low-temperature crude oil intermediate product inlet and a high-temperature crude oil intermediate product outlet, and the low-temperature crude oil intermediate product outlet (11) of the primary separator (1) is connected to the low-temperature crude oil intermediate product inlet of the condenser (21) via a pipeline; a secondary separator (3) provided with a high-temperature crude oil intermediate product inlet (31) and a target crude oil outlet (32); the high-temperature crude oil intermediate product outlet of the condenser (21) and the high-temperature crude oil intermediate product inlet (31) of the secondary separator (3) being connected via a pipeline; Wherein, the initial crude oil inlet (10) is used to receive the initial crude oil; The initial crude oil is separated and processed in a primary separator (1) to produce a low-temperature crude oil intermediate product; The low-temperature crude oil intermediate product is converted into a high-temperature crude oil intermediate product through heat exchange in a heat pump device (2); The high-temperature crude oil intermediate product is separated and processed in a secondary separator (3) to generate target crude oil; The target crude oil outlet (32) is used to discharge the target crude oil.

2. The offshore crude oil processing device according to claim 1, characterized in that: The heat pump device (2) further comprises a compressor (20), an expansion valve (22) and an evaporator (23); the compressor (20), the condenser (21), the expansion valve (22) and the evaporator (23) all comprise a refrigerant inlet and an outlet; the refrigerant inlets and outlets of the compressor (20), the condenser (21), the expansion valve (22) and the evaporator (23) are connected end to end in sequence to form a refrigerant circulation loop; The high-temperature crude oil intermediate product will also produce high-temperature water after being separated and processed by the secondary separator (3); The secondary separator (3) is further provided with a high-temperature water outlet (33), and the evaporator (23) is further provided with a high-temperature water inlet and a low-temperature water outlet (230) for discharging to the sea, and the low-temperature water outlet (230) is connected to the high-temperature water inlet, and the high-temperature water outlet (33) of the secondary separator (3) is connected to the high-temperature water inlet of the evaporator (23) through a pipeline; When the high-temperature water flowing out of the high-temperature water outlet (33) of the secondary separator (3) passes through the evaporator (23), it transfers heat to the refrigerant in the evaporator (23) and turns into low-temperature water, and the low-temperature water is discharged through the low-temperature water outlet (230).

3. The offshore crude oil processing device according to claim 1, characterized in that: The refrigerant inlet and outlet of the compressor (20) are respectively a high-temperature, low-pressure gaseous refrigerant inlet and a high-temperature, high-pressure gaseous refrigerant outlet; The refrigerant inlet and outlet of the condenser (21) are respectively a high-temperature and high-pressure gaseous refrigerant inlet and a low-temperature and high-pressure liquid refrigerant outlet. The refrigerant inlet and outlet of the expansion valve (22) are respectively a low-temperature and high-pressure liquid refrigerant inlet and a low-temperature and low-pressure liquid refrigerant outlet. The refrigerant inlet and outlet of the evaporator (23) are respectively a low-temperature and low-pressure liquid refrigerant inlet and a high-temperature and low-pressure gaseous refrigerant outlet. The high-temperature and high-pressure gaseous refrigerant outlet of the compressor (20) is connected to the high-temperature and high-pressure gaseous refrigerant inlet of the condenser (21) through a pipeline, the low-temperature and high-pressure liquid refrigerant outlet of the condenser (21) is connected to the low-temperature and high-pressure liquid refrigerant inlet of the expansion valve (22) through a pipeline, the low-temperature and low-pressure liquid refrigerant outlet of the expansion valve (22) is connected to the low-temperature and low-pressure liquid refrigerant inlet of the evaporator (23) through a pipeline, and the high-temperature and low-pressure gaseous refrigerant outlet of the evaporator (23) is connected to the high-temperature and low-pressure gaseous refrigerant inlet of the compressor (20) through a pipeline, thereby forming a refrigerant circulation loop; The compressor (20) is used to compress a high-temperature, low-pressure gaseous refrigerant into a high-temperature, high-pressure gaseous refrigerant; The condenser (21) is used to transfer the heat of the high-temperature and high-pressure gaseous refrigerant to the intermediate product of crude oil, so that the high-temperature and high-pressure gaseous refrigerant is cooled and condensed into a liquid state, becoming a low-temperature and high-pressure liquid refrigerant, and at the same time releases heat to heat the intermediate product of crude oil, so that the low-temperature intermediate product of crude oil is heated and becomes a high-temperature intermediate product of crude oil; The expansion valve (22) is used to throttle and reduce the pressure of the low-temperature and high-pressure liquid refrigerant, returning it to a low-temperature and low-pressure state, and turning it into a low-temperature and low-pressure liquid refrigerant; The evaporator (23) is used to absorb the heat released when the high-temperature water passes through the evaporator (23) to heat the low-temperature, low-pressure liquid refrigerant, so that the low-temperature, low-pressure liquid refrigerant is converted into a high-temperature, low-pressure gaseous refrigerant, and at the same time, the temperature of the high-temperature water is reduced to become low-temperature water.

4. The offshore crude oil processing device according to claim 1, characterized in that: The first-stage separator (1) is an oil-water two-phase separator, and is further provided with a free water outlet (12). The free water outlet (12) is used to discharge free water generated when the initial crude oil is separated and processed by the first-stage separator (1).

5. The offshore crude oil processing device according to claim 1, characterized in that: The secondary separator (3) is an oil, gas and water three-phase separator, and is also provided with a gas outlet (34). The gas outlet (34) is used to discharge the gas released when the high-temperature crude oil intermediate product is separated and processed by the secondary separator (3).

6. A method for processing offshore crude oil, using the offshore crude oil processing device according to any one of claims 1 to 5, characterized in that: include The initial crude oil enters the primary separator (1) through the initial crude oil inlet (10) of the primary separator (1); The first-stage separator (1) performs preliminary separation treatment on the initial crude oil, removes some free water, and generates a low-temperature crude oil intermediate product; The low-temperature crude oil intermediate product flows out from the low-temperature crude oil intermediate product outlet (11) and enters the condenser (21) through the low-temperature crude oil intermediate product inlet of the condenser (21); The condenser (21) transfers the heat of the refrigerant to the intermediate product of the crude oil to increase the temperature of the intermediate product of the crude oil, thereby increasing the temperature of the low-temperature intermediate product of the crude oil to become a high-temperature intermediate product of the crude oil; The high-temperature crude oil intermediate product flows out from the high-temperature crude oil intermediate product outlet of the condenser (21) and enters the secondary separator (3) through the high-temperature crude oil intermediate product inlet (31) of the secondary separator (3); The secondary separator (3) separates and processes the high-temperature crude oil intermediate product to generate liquid target crude oil, which flows out through the target crude oil outlet (32).

7. The offshore crude oil processing method according to claim 6, characterized in that: While the secondary separator (3) is performing a three-phase separation process on the high-temperature crude oil intermediate product, the refrigerant circulates in the refrigerant circulation loop. The circulation steps are as follows: A high-temperature, low-pressure gaseous refrigerant enters the compressor (20) and is compressed by the compressor (20) into a high-temperature, high-pressure gaseous refrigerant; The high-temperature and high-pressure gas refrigerant enters the condenser (21), and the condenser (21) transfers the heat of the refrigerant to the intermediate product of crude oil, cooling and condensing the high-temperature and high-pressure gas refrigerant into a liquid state, thereby converting it into a low-temperature and high-pressure liquid refrigerant. At the same time, the heat is released to heat the intermediate product of crude oil, thereby increasing the temperature of the low-temperature intermediate product of crude oil and converting it into a high-temperature intermediate product of crude oil. The low-temperature and high-pressure liquid refrigerant passes through the expansion valve (22) to be throttled and depressurized, and returns to a low-temperature and low-pressure state, becoming a low-temperature and low-pressure liquid refrigerant; The low-temperature, low-pressure liquid refrigerant enters the evaporator (23) and exchanges heat with the high-temperature water generated by separating the high-temperature crude oil intermediate product in the secondary separator (3). The low-temperature, low-pressure liquid refrigerant absorbs heat and evaporates into a gaseous state, becoming a high-temperature, low-pressure gaseous refrigerant. The high-temperature, high-pressure gaseous refrigerant re-enters the compressor (20), forming a refrigerant circulation in the heat pump device (2).

8. The offshore crude oil processing method according to claim 6, characterized in that: When the primary separator (1) performs preliminary separation on the initial crude oil, the separated free water flows out from the free water outlet (12); When the secondary separator (3) separates and processes the high-temperature crude oil intermediate product, gas is also released and high-temperature water is generated. The released gas flows out through the released gas outlet (34), and the high-temperature water flows out through the high-temperature water outlet (33).

9. The offshore crude oil processing method according to claim 6, characterized in that: During the circulation of the refrigerant in the refrigerant circulation loop, the condenser (21) simultaneously receives the high-temperature and high-pressure refrigerant and the low-temperature crude oil intermediate product flowing out of the low-temperature crude oil intermediate product outlet (11) of the first-stage separator (1). The low-temperature crude oil intermediate product exchanges heat with the high-temperature and high-pressure refrigerant in the condenser (21), and the low-temperature crude oil intermediate product becomes a high-temperature crude oil intermediate product, while the high-temperature and high-pressure refrigerant becomes a low-temperature and high-pressure refrigerant.

10. The offshore crude oil processing method according to claim 6, characterized in that: During the circulation of the refrigerant in the refrigerant circulation loop, the evaporator (23) simultaneously receives high-temperature water and low-temperature, low-pressure liquid refrigerant flowing out of the high-temperature water outlet (33) of the secondary separator (3), and the low-temperature, low-pressure liquid refrigerant exchanges heat with the high-temperature water, and the low-temperature, low-pressure liquid refrigerant is converted into a high-temperature, low-pressure gaseous refrigerant. At the same time, the temperature of the high-temperature water is reduced to become low-temperature water, and the low-temperature water flows out of the low-temperature water sea outlet (230) of the evaporator (23) and is discharged into the sea.

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