阅读说明：本技术 一种利用超临界水热改质和延迟焦化技术处理重油的方法 (Method for treating heavy oil by supercritical hydrothermal modification and delayed coking technology ) 是由 范景新 靳凤英 臧甲忠 李福双 吴青 薛同晖 董子超 李世松 刘晗 唐成义 隋芝 于 2021-09-10 设计创作，主要内容包括：本发明公开了一种利用超临界水热改质和延迟焦化技术处理重油的方法。该方法包括以下内容：对油品和去离子水分别加热和增压,将油水混合后再次加热,并传输到超临界反应器中进行热解反应；对于超临界反应后的产物进行初步的降温降压,使其脱离超临界态后便通入蒸馏塔进行分离以及进行后续的延迟焦化反应。该方法能够对稠油和超稠油进行改质,降低其黏度,同时通过超临界工艺和延迟焦化工艺的耦合提高了稠油的处理效率,实现了热量的高效利用,降低系统能耗。(The invention discloses a method for treating heavy oil by utilizing supercritical hydrothermal modification and delayed coking technologies. The method comprises the following steps: respectively heating and pressurizing an oil product and deionized water, mixing the oil and the water, then heating again, and transmitting the mixture to a supercritical reactor for pyrolysis reaction; and (3) carrying out primary temperature reduction and pressure reduction on the product after the supercritical reaction, and introducing the product into a distillation tower for separation and subsequent delayed coking reaction after the product is separated from the supercritical state. The method can modify the heavy oil and the super heavy oil, reduce the viscosity of the heavy oil and the super heavy oil, and simultaneously improve the treatment efficiency of the heavy oil through the coupling of the supercritical process and the delayed coking process, thereby realizing the high-efficiency utilization of heat and reducing the energy consumption of a system.)

1. A method for treating heavy oil by supercritical hydrothermal upgrading and delayed coking technology comprises the following steps:

1) heating deionized water to 50-90 ℃, pressurizing to 22.1-30 MPa, absorbing heat through a heat exchanger, conveying to an inlet of a mixer, heating an oil product to 50-90 ℃, pressurizing to 22.1-30 MPa, conveying to the inlet of the mixer, mixing the oil product and the deionized water in the mixer to obtain an oil-water mixed solution, heating the oil-water mixed solution to the supercritical temperature of water of 374-450 ℃, and conveying to the inlet of a supercritical reactor, wherein the mass flow ratio of the oil product to the deionized water is 0.2-4;

2) the oil product is subjected to a pyrolysis reaction in the supercritical reactor, the retention time of the oil product in the supercritical reactor is 1 s-40 min, the mixed fluid of supercritical water, modified oil and cracked gas generated by the reaction is discharged from an upper outlet of the supercritical reactor, the temperature is reduced to 200-350 ℃, the pressure is reduced to 1MPa by a hydraulic turbine, and the mixed fluid is conveyed into a distillation tower;

3) and (2) separating the mixed fluid obtained in the step 2) and oil gas from the top of a coking tower in a distillation tower, condensing light components discharged from the top of the distillation tower to obtain cracked gas, gasoline and water, discharging diesel oil and light wax oil from the side of the distillation tower, mixing the light wax oil with the weight of 10-30% of that of oil in the bottom of the distillation tower and the oil in the bottom of the distillation tower to obtain a mixture, conveying the mixture to a heating furnace, heating to 450-520 ℃, introducing the mixture into the coking tower to carry out coking reaction, wherein the pressure of the coking tower is 0.1-0.2 MPa to obtain oil gas and coke, discharging the coke from the bottom of the coking tower, and separating the oil gas in the distillation tower.

2. The method for treating heavy oil by utilizing supercritical hydrothermal upgrading and delayed coking technology as claimed in claim 1, wherein the pressure of the deionized water and the oil product after pressurization in step 1) is 22.1-25 MPa.

3. The method for treating heavy oil by utilizing supercritical hydrothermal upgrading and delayed coking technology according to claim 1, wherein the mass flow ratio of the oil product in the step 1) and the deionized water is 1-2.

4. The method for treating heavy oil by supercritical hydrothermal upgrading and delayed coking technology according to claim 1, wherein the temperature of the oil-water mixed solution in step 1) after being heated is 374-430 ℃.

5. The process for treating heavy oil by supercritical hydrothermal upgrading and delayed coking technology of claim 1, wherein the supercritical reactor of step 2) is a riser upflow reactor.

6. The method for treating heavy oil by supercritical hydrothermal upgrading and delayed coking technology according to claim 1, wherein the residence time in the supercritical reactor in step 2) is 1-10 min.

7. The method for treating heavy oil by supercritical hydrothermal upgrading and delayed coking technology according to claim 1, wherein the mass of the extracted light wax oil in the step 3) is 10-15% of the mass of the distillation tower bottom oil.

Technical Field

The invention relates to the technical field of heavy oil processing and utilization, in particular to a method for modifying oil products by supercritical water thermal modification and delayed coking technology.

Background

The social development leads to the gradual shortage of petroleum resources, presents more obvious trends of deterioration and heaviness at present, and greatly increases the difficulty of petroleum production and processing. In crude oil extracted in China, the heavy oil accounts for more than 50 percent. However, the demand of the social production on petroleum shows the trend of cleanness and lightening, and the lightening processing of heavy oil is more difficult.

The supercritical water has particularly strong thermal conductivity, fluidity and thermal conductivity, has better lightening and viscosity reducing effects when being applied to oil modification, and can effectively inhibit heavy oil from coking. However, when supercritical hydrothermal upgrading of heavy oil is applied, a high reaction temperature is required to obtain a good reaction result, and when the reaction temperature is higher than 420 ℃, the amount of coke formation is significantly increased, which easily causes pipeline blockage.

Patent CN106170532A proposes a two-stage reaction mode using an upflow reactor and a downflow supercritical water reactor in series, which further upgrades the intermediates and low carbon hydrocarbon and heteroatom components that are not treated in the upflow reactor by increasing the temperature of the fluid in the downflow supercritical water reactor. The method increases the temperature in the reactor, can increase the upgrading effect to a certain extent, but the increase of the temperature also increases the coke formation amount and increases the risk of blocking pipelines and the reactor.

Patent CN103013550A sets up heating device inside supercritical water reactor, need heat up several hundred degrees behind the mixed material input reactor of tar sediment and water, and heating time is long, and this will lead to this system's handling capacity to be low, and simultaneously, near local temperature of heating device is too high, and the easy coke that grows of tar sediment blocks up the reactor inner space.

The delayed coking technology is a relatively mature thermal cracking technology, can improve the yield of light oil of heavy oil products and produce high-value liquid and gas products. Patent CN 109929580A proposes a novel delayed coking device, which uses catalytic slurry oil as the raw material for delayed coking, and mixes the catalytic slurry oil with high density, low viscosity, low carbon residue value and containing catalyst particles with residual oil and then enters the delayed coking device, so as to realize the stable treatment of the catalytic slurry oil.

Patent CN 110088240 a proposes a method for processing vacuum residue by using delayed coking technology, which can produce high viscosity and high density vacuum distillation residue into naphtha, gas oil and coke by delayed coking technology, and perform subsequent processing, thereby realizing high-efficiency utilization of residue.

CN 106675632B proposes a method for treating phenol tar by a delayed coking technology, which takes phenol tar as a byproduct of phenol production as a part of raw material to be mixed with conventional raw material and then to enter a delayed coking device, and the phenol tar which is difficult to treat originally is deeply processed by the delayed coking technology.

If the delayed coking technology is used for directly treating the heavy oil, the liquid yield of the delayed coking is low and the coke yield is high due to the high content of heavy components in the oil product, and the content of residual carbon and metal in the light oil can exceed the corresponding requirements. Meanwhile, the coke removal period of the device is short due to high coke yield, and the operation cost of the device is increased.

Disclosure of Invention

The invention aims to provide a method for heavy oil modification by supercritical hydrothermal modification and delayed coking technologies, and particularly relates to a method for realizing light-weight conversion of heavy oil by coupling supercritical hydrothermal modification and delayed coking technologies. The method comprises the steps of firstly carrying out primary modification and viscosity reduction on the thickened oil in a supercritical reactor to reduce the content of heavy components in the thickened oil, then carrying out delayed coking on the oil product subjected to primary modification to further modify the thickened oil, improve the quality of the oil product and reduce the viscosity of the oil product.

The invention relates to a method for treating heavy oil by utilizing supercritical hydrothermal upgrading and delayed coking technologies, which comprises the following treatment steps:

1) heating deionized water to 50-90 ℃, pressurizing to 22.1-30 MPa, absorbing heat through a heat exchanger, conveying to an inlet of a mixer, heating an oil product to 50-90 ℃, pressurizing to 22.1-30 MPa, conveying to the inlet of the mixer, mixing the oil product and the deionized water in the mixer to obtain an oil-water mixed solution, heating the oil-water mixed solution to the supercritical temperature of water of 374-450 ℃, and conveying to the inlet of a supercritical reactor, wherein the mass flow ratio of the oil product to the deionized water is 0.2-4;

2) the oil product is subjected to a pyrolysis reaction in the supercritical reactor, the retention time of the oil product in the supercritical reactor is 1 s-40 min, the mixed fluid of supercritical water, modified oil and cracked gas generated by the reaction is discharged from an upper outlet of the supercritical reactor, the temperature is reduced to 200-350 ℃, the pressure is reduced to 1MPa by a hydraulic turbine, and the mixed fluid is conveyed into a distillation tower;

3) and (2) separating the mixed fluid obtained in the step 2) and oil gas from the top of a coking tower in a distillation tower, condensing light components discharged from the top of the distillation tower to obtain cracked gas, gasoline and water, discharging diesel oil and light wax oil from the side of the distillation tower, mixing the light wax oil with the weight of 10-30% of that of oil in the bottom of the distillation tower and the oil in the bottom of the distillation tower to obtain a mixture, conveying the mixture to a heating furnace, heating to 450-520 ℃, introducing the mixture into the coking tower to carry out coking reaction, wherein the pressure of the coking tower is 0.1-0.2 MPa to obtain oil gas and coke, discharging the coke from the bottom of the coking tower, and separating the oil gas in the distillation tower.

In the method for treating heavy oil by using supercritical hydrothermal modification and delayed coking technologies, the pressure of the deionized water and the oil product after pressurization in the step 1) is preferably 22.1-25 MPa.

In the method for treating heavy oil by using supercritical hydrothermal modification and delayed coking technologies, the mass flow ratio of the oil product and deionized water in the step 1) is 1-2.

In the method for treating heavy oil by supercritical hydrothermal upgrading and delayed coking technology, the temperature of the oil-water mixed solution in the step 1) after being heated is preferably 374-430 ℃.

In the above method for treating heavy oil by supercritical hydrothermal upgrading and delayed coking technology, the supercritical reactor in step 2) is a riser upflow reactor.

In the method for treating heavy oil by using supercritical hydrothermal modification and delayed coking technology, the residence time in the supercritical reactor in the step 2) is preferably 1-10 min.

In the method for treating heavy oil by using supercritical hydrothermal modification and delayed coking technology, the mass of the extracted light wax oil in the step 3) is preferably 10-15% of that of the oil at the bottom of the distillation tower.

Compared with the prior art, the invention has the beneficial effects that: according to the invention, the delayed coking process and the supercritical hydrothermal modification technology are coupled to continuously modify and reduce viscosity of the heavy oil, so that the coking condition in the supercritical reaction process is reduced, the yield of the light oil in the delayed coking process is improved after the supercritical hydrothermal modification primary treatment, the heat in the supercritical reaction process is reused in the subsequent delayed coking reaction, the utilization efficiency of energy is improved, the continuous reaction is adopted, the continuous reaction can be continuously carried out, the treatment capacity is large, and the industrial scale-up production can be realized. The heavy oil subjected to supercritical hydrothermal modification and delayed coking treatment can be greatly modified and viscosity reduced, the viscosity reduction rate is higher than 90%, and the yield of non-heavy oil components is higher than 60%.

Drawings

FIG. 1 is a general schematic diagram of one embodiment of the process of the present invention for treating heavy oil using supercritical hydrothermal upgrading and delayed coking techniques.

Description of the reference numerals

The system comprises a water heater 1, a water booster pump 2, a heat exchanger 3, a supercritical reactor 4, a raw material heater 5, a mixer 6, an oil booster pump 7, a hydraulic turbine 8, a heater 9, a mixed oil pump 10, a three-way ball valve 11, a coking tower 12, an oil-water separation tank 13, a tower top condenser 14, a distillation tower 15, a reflux ratio control valve 16 and a heating furnace 17.

101 is deionized water, 102 is an oil product material flow, 103 is modified oil, 104 is a product of coking reaction, 105 is pyrolysis gas, 106 is gasoline, 107 is water, 108 is diesel oil, and 109 is light wax oil.

Detailed Description

The invention relates to a method for treating heavy oil by utilizing supercritical hydrothermal upgrading and delayed coking technologies, which comprises the following treatment steps:

1) heating deionized water to 50-90 ℃, pressurizing to 22.1-30 MPa, absorbing heat through a heat exchanger, conveying to an inlet of a mixer, heating an oil product to 50-90 ℃, pressurizing to 22.1-30 MPa, conveying to the inlet of the mixer, mixing the oil product and the deionized water in the mixer to obtain an oil-water mixed solution, heating the oil-water mixed solution to the supercritical temperature of water of 374-450 ℃, and conveying to the inlet of a supercritical reactor, wherein the mass flow ratio of the oil product to the deionized water is 0.2-4;

2) the oil product is subjected to a pyrolysis reaction in the supercritical reactor, the retention time of the oil product in the supercritical reactor is 1 s-40 min, the mixed fluid of supercritical water, modified oil and cracked gas generated by the reaction is discharged from an upper outlet of the supercritical reactor, the temperature is reduced to 200-350 ℃, the pressure is reduced to 1MPa by a hydraulic turbine, and the mixed fluid is conveyed into a distillation tower;

3) and (2) separating the mixed fluid obtained in the step 2) and oil gas from the top of a coking tower in a distillation tower, condensing light components discharged from the top of the distillation tower to obtain cracked gas, gasoline and water, discharging diesel oil and light wax oil from the side of the distillation tower, mixing the light wax oil with the weight of 10-30% of that of oil in the bottom of the distillation tower and the oil in the bottom of the distillation tower to obtain a mixture, conveying the mixture to a heating furnace, heating to 450-520 ℃, introducing the mixture into the coking tower to carry out coking reaction, wherein the pressure of the coking tower is 0.1-0.2 MPa to obtain oil gas and coke, discharging the coke from the bottom of the coking tower, and separating the oil gas in the distillation tower.

In the method for treating heavy oil by supercritical hydrothermal modification and delayed coking technology, the pressure of the deionized water and the oil product after pressurization in the step 1) is preferably 22.1-25 MPa.

In the method for treating heavy oil by using the supercritical hydrothermal modification and delayed coking technology, the mass flow ratio of the oil product in the step 1) and the deionized water is 1-2. .

In the method for treating heavy oil by supercritical hydrothermal modification and delayed coking technology, the temperature of the oil-water mixed solution in the step 1) after being heated is preferably 374-430 ℃.

In the method for treating heavy oil by supercritical hydrothermal modification and delayed coking technology, the residence time in the supercritical reactor in the step 2) is preferably 1-10 min.

In the above supercritical hydrothermal upgrading and delayed coking process for heavy oil treatment, the supercritical reactor in step 2) is a riser upflow reactor.

In the method for treating heavy oil by supercritical hydrothermal modification and delayed coking technology, the operating temperature of the distillation tower in the step 3) is preferably 390-410 ℃.

In the method for treating heavy oil by supercritical hydrothermal modification and delayed coking technology, the mass of the extracted light wax oil in the step 3) is preferably 10-15% of that of the oil at the bottom of the distillation tower.

The present invention will be further described in the following detailed description with reference to the drawings, but the invention is not limited thereto.

As shown in figure 1, deionized water flow 101 is heated to 50-90 ℃ by a water heater 1, is pressurized to 22.1-30 MPa by a water booster pump 2, absorbs heat by a heat exchanger 3, and is conveyed to an inlet of a mixer 6. An oil product raw material flow 102 is heated to 50-90 ℃ by a heater 9, is pressurized to 22.1-30 MPa by a hydraulic turbine 8 and an oil booster pump 7, and is conveyed to an inlet of a mixer 6. The mass flow of the oil product is 0.2-4 times of the mass flow of the deionized water flow. Mixing the oil product and the deionized water in the mixer 6 to obtain an oil-water mixed solution, heating the oil-water mixed solution to the supercritical temperature of 374-450 ℃ of water in the raw material heater 5, and then conveying the oil-water mixed solution to the inlet of the supercritical reactor 4, wherein the retention time in the supercritical reactor is 1 s-40 min. Discharging the reacted product through the outlet of the reactor 4, exchanging heat with deionized water flow through a heat exchanger 6, reducing the pressure to 1MPa through a hydraulic turbine 8, conveying the mixed fluid which is separated from the supercritical state into a distillation tower 15, the operating temperature of the distillation tower is 350-410 ℃, the mixed fluid is separated in the distillation tower, light components discharged from the top of the distillation tower are condensed to obtain cracked gas 105, gasoline 106 and water 107, diesel oil 108 and light wax oil 109 are discharged from the side of the distillation tower, the residual components in the bottom of the distillation tower are heavy wax oil and residual oil, the light wax oil with the extracted mass being 10-30% of the mass of the oil in the bottom of the distillation tower is mixed with the oil in the bottom of the distillation tower, the mixture is conveyed to a heating furnace 17, the mixture is heated to 450-520 ℃, the mixture is introduced into a coking tower 12 for coking reaction, the pressure of the coking tower is 0.1-0.2 MPa, oil gas and coke are obtained, the coke is discharged from the bottom of the coking tower, and the oil gas enters a distillation tower 15 for separation.

The present invention will be described in detail below by way of examples, but the present invention is not limited thereto.

Example 1

This example illustrates the process of the present invention for treating heavy oil by supercritical hydrothermal upgrading and delayed coking.

The flow of heavy oil treatment in this example is shown in FIG. 1:

in the embodiment, oil sand bitumen is used as a raw material, the oil properties are shown in table 1, and the mass ratio of deionized water to oil sand bitumen is 2: 1, heating the oil raw material and deionized water to 60 ℃, pressurizing by a diaphragm pump and a hydraulic turbine to 23MPa, heating the oil-water mixed solution to 350 ℃ by a heater, and conveying the oil-water mixed solution to an inlet of a supercritical reactor. The oil product is subjected to pyrolysis reaction in the supercritical reactor for 20min, the mixture of supercritical water, modified oil product and cracked gas generated by the reaction is discharged from the upper outlet of the supercritical reactor, and exchanges heat with deionized water flow through a heat exchanger, and is transmitted to a distillation tower after being decompressed by a hydraulic turbine, separating the mixed fluid in a distillation tower, condensing light components discharged from the top of the distillation tower to obtain cracked gas, gasoline and water, discharging diesel oil and light wax oil from the side of the distillation tower, mixing the light wax oil with the extracted mass being 10% of the mass of the oil in the bottom of the distillation tower with the oil in the bottom of the distillation tower, conveying the mixture to a heating furnace, heating to 450 ℃, introducing the mixture into the coking tower to carry out coking reaction to obtain oil gas and coke, discharging the coke from the bottom of the coking tower, and separating the oil gas from the distillation tower.

The yield and the viscosity reduction rate of each component can be calculated by detecting the viscosity of the products of the distillation tower and the coking tower and the viscosity of the oil product raw material. The product analysis results are shown in Table 3.

Example 2

This example uses the same processing system and bitumen from oil sands as example 1, but with the difference in processing conditions:

in the embodiment, the mass ratio of the deionized water to the oil sand asphalt is 1: 1, the reaction temperature of the supercritical reaction is 450 ℃, the pressure is 24MPa, the reaction time of the supercritical reaction is 10min, the temperature of the delayed coking heating furnace is 520 ℃, and other reaction conditions are the same as those in the embodiment 1.

The results of the product analysis obtained in this example are shown in Table 3.

Example 3

This example uses the same processing system and bitumen from oil sands as example 1, but with the difference in processing conditions:

in this embodiment, the mass ratio of the deionized water to the oil sand bitumen is 3: 1, the reaction temperature of the supercritical reaction is 400 ℃, the pressure is 22MPa, the reaction time of the supercritical reaction is 1min, and the temperature of the delayed coking furnace is 480 ℃.

The results of the product analysis obtained in this example are shown in Table 3.

Comparative example 1

Adding an oil sand asphalt raw material into a kettle type reactor, purging with nitrogen for 10min to fill a gas phase space in the kettle with nitrogen, continuously filling the nitrogen to 2MPa, sealing the kettle type reactor and starting heating, keeping the temperature for 5min after the temperature reaches 400 ℃, and carrying out thermal cracking reaction on the oil sand asphalt under the high-temperature condition. Immediately cooling the kettle reactor after the thermal cracking reaction is finished, and taking out the product for analysis when the temperature is reduced to 50 ℃, wherein the analysis result of the product is shown in Table 3.

TABLE 1 oil sand bitumen feedstock Properties

Item	Unit of
			Density (20 ℃ C.)	g·cm-3	1.044
Viscosity (50 ℃ C.)	cp	77024
			Carbon residue	Mass%	16.1
Four components
			Saturation fraction	Mass%	26.7
Aromatic component	Mass%	38.0
			Glue	Mass%	22.5
Asphaltenes	Mass%	12.8
			Sulfur content	Mass%	5.3

TABLE 2 operating conditions

TABLE 3 oil modified data

It should be understood that the above-mentioned embodiments are only illustrative of the technical concepts and features of the present invention, and the purpose of the present invention is to enable people to understand the contents of the present invention and implement the present invention, and not to limit the protection scope of the present invention. All equivalent changes or modifications made according to the spirit of the main technical scheme of the invention are covered in the protection scope of the invention.