Heavy oil resource utilization method and system

Abstract

The invention relates to a heavy oil resource utilization method and system, filtrate separated from solid ash-containing water and water-containing filter residues are treated respectively, reuse water and crystal salt are obtained from the filtrate, reuse metal is obtained from the water-containing filter residues, on one hand, metal in a heavy oil raw material can be recycled, the quality of the recycled metal is high, and on the other hand, the heavy oil can be recycled; the problem that metal in the gasified ash cannot be recycled or the recycling cost is too high is solved, and the problem of environmental pollution caused by direct combustion or landfill is avoided; on the other hand, salt and water in the water phase in the system can be recycled, the utilization rate of heavy oil resources can be increased, the use amount of externally-supplemented water can be reduced, and the competitiveness of the heavy oil gasification technology is further improved. Besides, by adopting the method disclosed by the invention, high-quality crystalline salt and recycled water can be obtained, near-zero emission of high-salt wastewater can be realized, efficient recycling of salt and water can be improved, and further energy consumption and harm to the environment are reduced.

Description

Technical Field

[0001] The present disclosure relates to the field of petrochemical engineering, and in particular, to a method and system for resource utilization of heavy oil. Background Art

[0002] As people's demand for energy increases day by day, fossil energy is becoming increasingly depleted. How to efficiently and cleanly utilize every chemical molecule in energy has become one of the hot topics in today's energy research field. Among them, coal and petroleum (petroleum coke, residual oil, oil residue, asphalt, heavy oil) in fossil energy can be used to produce synthesis gas by gasification to achieve efficient and clean utilization to the maximum extent, and then the synthesis gas can be processed into chemical products or clean energy such as olefins, methanol, urea, hydrogen, etc. to meet the diverse needs of society.

[0003] Pressurized entrained flow gasification technology is recognized as one of the more advanced gasification technologies. Gasification feed is mainly in powder form and slurry form, and a gasifying agent is required as a conveying medium to deliver it to the gasifier. After being atomized by the burner, the feed is fully mixed with the gasifier to undergo intense pyrolysis, combustion and gasification reactions, resulting in a crude synthesis gas mainly composed of carbon monoxide and hydrogen and a small amount of solid slag. The more common pressurized entrained flow gasification technologies are Texaco furnaces, Shell furnaces and Huali's multi-burner furnaces.

[0004] Coal gasification is currently the most widely used mainstream technology. The chemical water consumption of entrained flow gasification (dry or wet feed) for gasification reaction is about 0.3 tons / ton of coal, which is less than 1 / 10 of the physical water consumption for quenching and washing. As a result, it has high water consumption, high pollution (black water, saline wastewater and ash) and high energy consumption, which has been criticized. At the same time, due to the increasingly obvious trend of heavy and inferior quality due to domestic processing reasons and the dual constraints of environmental protection regulations, how to cleanly and efficiently utilize heavy and inferior oil has become a hot topic of current research. Due to the strong adaptability of raw materials in the heavy oil gasification process and the relatively low cost of hydrogen production, oil gasification technology has developed rapidly in recent years. Oil gasification technology can not only process inferior heavy oil, but also produce high value-added synthesis gas. It is a clean production technology with great development prospects.

[0005] However, in the existing technology, heavy oil gasification technology has the disadvantages of complex system, long process, poor gas-solid separation effect, easy clogging and high energy consumption. At the same time, the device operation cycle is short, the emission of three wastes is large, there are poor raw material adaptability and low operational flexibility. Summary of the invention

[0006] The purpose of the present disclosure is to provide a method and system for resource utilization of heavy oil to solve the problems of short operation cycle, high energy consumption and environmental pollution in the prior art.

[0007] In order to achieve the above-mentioned purpose, the first aspect of the present disclosure provides a method for resource utilization of heavy oil, which method comprises: S1, allowing oxygen, water vapor and heavy oil raw materials to enter a gasification unit for oxidation reaction, and then cooling them with quenching water to obtain an oxidation reaction product containing crude synthesis gas and ash-containing black water; allowing the oxidation reaction product to undergo a first separation treatment to obtain purified synthesis gas, acid gas, acid water and low-pressure solid-containing ash water; S2, allowing the low-pressure solid-containing ash water to enter a slag-water separation unit for a second separation treatment to obtain a filtrate and a water-containing filter residue; S3, allowing the filtrate to enter a crystallization salt unit for crystallization treatment to obtain a first recycled water, crystallization salt and an external mother liquor; allowing the external mother liquor to enter a final mother liquor treatment unit for drying treatment to obtain a mixed salt solid; S4, allowing the water-containing filter residue to enter a metal recovery unit for metal recovery treatment to obtain recovered metal.

[0008] Optionally, the heavy oil feedstock is selected from one or more of residual oil, deoiled asphalt, deasphalted oil, coal tar, shale oil and crude oil; the purity of the oxygen is above 99.8% by volume; and the water vapor is selected from one or more of low-pressure steam, medium-pressure steam, high-pressure steam and ultra-high-pressure steam.

[0009] Optionally, the oxidation reaction product includes crude synthesis gas and ash-containing black water; the first separation treatment described in step S1 includes: S11, allowing the crude synthesis gas to enter a separation and purification device for separation and purification treatment to obtain the purified synthesis gas and high-pressure solid-containing ash water; S12, allowing the ash-containing black water and the high-pressure solid-containing ash water to enter a gas-liquid separation device for gas-liquid separation to obtain the acid gas, the acid water and the low-pressure solid-containing ash water.

[0010] Optionally, the oxidation reaction conditions in step S1 include: being carried out in a gasifier, the gasification temperature is 950-1650°C, the gasifier pressure is 0.1MPaG-10MPaG, the crude synthesis gas at the outlet of the gasifier has a temperature of 200-450°C, a pressure of 0.1MPaG-10MPaG, and a particle content of less than 2000g / Nm 3 The solid particle content in the purified synthesis gas is less than 5 mg / Nm 3 .

[0011] Optionally, step S3 also includes: S31, allowing the filtrate to enter a homogenization adjustment device for homogenization treatment to obtain a homogenous filtrate; S32, allowing the homogenous filtrate to enter a pretreatment device for pretreatment reaction to obtain a pretreated filtrate; S33, allowing the pretreated filtrate to enter a crystallization salt separation device for the crystallization treatment; the crystallization salt separation device includes one or more of a membrane concentration device, a nanofiltration device, a reverse osmosis device and a salt crystallization device.

[0012] Optionally, step S3 also includes: S34, allowing the discharged mother liquor to enter a mother liquor concentration device for concentration treatment to obtain a final mother liquor; S35, allowing the final mother liquor to enter a mother liquor drying device for drying treatment to obtain the impure salt solid.

[0013] Optionally, step S4 also includes: S41, allowing the water-containing filter residue to enter a filter residue drying device for filter residue drying treatment to obtain a dry filter residue; S42, allowing the dry filter residue to enter an incineration device for incineration treatment to obtain an incineration product and incineration flue gas; S43, allowing the incineration product to enter a metal recovery unit for metal recovery treatment to obtain the recovered metal; S44, allowing the incineration flue gas to enter the mother liquor drying device as a heat medium to participate in the drying treatment.

[0014] Optionally, the metal recovery treatment includes mechanical crushing treatment, leaching treatment and precipitation treatment; the conditions of the leaching treatment include: leaching temperature of 50-150°C, leaching time of 1.0-10h, and leaching solution including leaching acid and / or leaching alkali solution; the conditions of the precipitation treatment include: precipitation temperature of 30-100°C, precipitation time of 0.5-10h, and precipitation solution including precipitation acid and / or precipitation alkali solution; the leaching acid and the precipitation acid are each independently selected from one or more of hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, hypochlorous acid, hydrofluoric acid and carbonic acid; the leaching alkali solution and the precipitation alkali solution are each independently selected from one or more of sodium hydroxide, potassium hydroxide and sodium carbonate.

[0015] Optionally, the method further comprises: S5, allowing the purified synthesis gas to enter a synthesis gas device; S6, allowing the acid gas to enter a sulfur recovery unit to recover sulfur; S7, allowing the acid water to enter an acid water stripping unit for stripping treatment to obtain second recycled water.

[0016] The second aspect of the present disclosure is a system for heavy oil resource utilization using the method shown in the first aspect, the system comprising a gasification unit, a first separation unit, a slag-water separation unit, a crystallization salt unit, a crystallization separation unit, a final mother liquor treatment unit and a metal recovery unit: the gasification unit comprises an oxygen inlet, a water vapor inlet, a heavy oil feedstock inlet and an oxidation reaction product outlet; the first separation unit comprises an oxidation reaction product inlet, a purified synthesis gas outlet, an acid gas outlet, an acid water outlet and a low-pressure solid ash-containing water outlet; the slag-water separation unit comprises a low-pressure solid ash-containing water inlet, a filtrate outlet and a water-containing filter residue outlet; the crystallization salt unit comprises a filtrate inlet and a mixed material outlet; the crystallization separation unit comprises a mixed material inlet, a first recycled water outlet, a crystallization salt outlet and an external mother liquor outlet inlet; the final mother liquor treatment unit includes an external mother liquor inlet and an impure salt solid outlet; the metal recovery unit includes an aqueous filter residue inlet and a recovered metal outlet; the oxidation reaction product outlet of the gasification unit is connected to the oxidation reaction product inlet of the first separation unit; the low-pressure solid-containing ash water outlet of the first separation unit is connected to the low-pressure solid-containing ash water inlet of the slag-water separation unit; the filtrate outlet of the slag-water separation unit is connected to the filtrate inlet of the crystallization salt unit; the mixed material outlet of the crystallization salt unit is connected to the mixed material inlet of the crystallization separation unit; the external mother liquor outlet of the crystallization separation unit is connected to the external mother liquor inlet of the final mother liquor treatment unit; the aqueous filter residue outlet of the slag-water separation unit is connected to the aqueous filter residue inlet of the metal recovery unit.

[0017] Through the above technical scheme, the present invention processes the filtrate and the water-containing filter residue separated from the solid ash water separately, obtains recycled water and crystallized salt from the filtrate, and obtains recycled metal from the water-containing filter residue. On the one hand, the metal in the heavy oil raw material can be recovered and the quality of the recovered metal is high, which solves the problem that the metal in the gasification ash cannot be recovered or the recovery cost is too high, and avoids environmental pollution caused by direct combustion or landfill; wherein, the total metal recovery rate is maintained at more than 90%; on the other hand, the salt and water in the aqueous phase of the system can be recovered, which can improve the utilization rate of heavy oil resources and reduce the use of external water, further improving the competitiveness of heavy oil gasification technology, wherein the recovery rate of crystallized salt is not less than 90% and the recovery rate of recycled water is not less than 75%. In addition, by adopting the method disclosed in the present invention, high-quality crystalline salt and recycled water can be obtained, which can not only achieve near-zero discharge of high-salt wastewater, but also improve the efficient recycling of salt and water, thereby reducing energy consumption and harm to the environment; wherein the obtained crystalline salt includes sodium sulfate crystalline salt that meets the first-class standard of Class I salt in the GB / T 6009-2014 "Industrial Anhydrous Sodium Sulfate" standard and sodium chloride crystalline salt that meets the first-class standard of refined industrial dry salt in the GB / T 5462-2015 "Industrial Salt" standard; and the recycled recycled water does not require secondary treatment or only needs simple treatment to obtain recycled water quality that meets the "Water Quality Standard for Recycled Water for Circulating Cooling Water HG-T3923-2007" standard.

[0018] Other features and advantages of the present disclosure will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings are used to provide a further understanding of the present disclosure and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present disclosure but do not constitute a limitation of the present disclosure. In the accompanying drawings:

[0020] Figure 1 The present invention discloses a process flow chart of a system for resource utilization of heavy oil.

[0021] Figure 2 is a schematic diagram of a venturi scrubber of the present disclosure.

[0022] Description of Reference Numerals

[0023] 20. Purification of synthesis gas; 1. Acid gas; 2. Low-pressure solid ash water; 3. Acid water; 4. Filtrate; 5. Homogenized filtrate; 6. Pre-treated filtrate; 7. First recycled water; 8. Crystallized salt; 9. Exhaust mother liquor; 10. Final mother liquor; 11. Miscellaneous salt solids; 12. Water-containing filter residue; 13. Dry filter residue; 14. Incineration flue gas; 15. Incineration products; 16. Metal recovery; 17. Ash; 101. Gasification unit; 102. Sulfur recovery unit; 103. Acid water stripping unit; 104. Slag water separation unit; 105. Homogenization regulating device; 106. Pre-treatment device; 107. Crystallization salt separation device; 108. Mother liquor concentration device; 109. Mother liquor drying device; 110. Filter residue drying device; 111. Incineration device; 112. Metal recovery device;

[0024] a1, synthesis gas inlet; a2, washing water inlet; a3, synthesis gas outlet. DETAILED DESCRIPTION

[0025] The specific implementation of the present disclosure is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described herein is only used to illustrate and explain the present disclosure, and is not used to limit the present disclosure.

[0026] In the present disclosure, the terms "first, second, third" are used for descriptive purposes only, unless otherwise specified, and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first, second, third" may explicitly or implicitly include one or more of the feature. In the description of the present disclosure, "plurality" means two or more, unless otherwise clearly and specifically defined.

[0027] The first aspect of the present disclosure provides a method for resource utilization of heavy oil, which comprises: S1, allowing oxygen, water vapor and heavy oil raw materials to enter a gasification unit for oxidation reaction, and then cooling with quenching water to obtain an oxidation reaction product containing crude synthesis gas and ash-containing black water; allowing the oxidation reaction product to undergo a first separation treatment to obtain purified synthesis gas, acid gas, acid water and low-pressure solid-containing ash water; S2, allowing the low-pressure solid-containing ash water to enter a slag-water separation unit for a second separation treatment to obtain a filtrate and a water-containing filter residue; S3, allowing the filtrate to enter a crystallization salt unit for crystallization treatment to obtain a first recycled water, crystallization salt and an external mother liquor; allowing the external mother liquor to enter a final mother liquor treatment unit for drying treatment to obtain a mixed salt solid; S4, allowing the water-containing filter residue to enter a metal recovery unit for metal recovery treatment to obtain recovered metal.

[0028] Through the above technical scheme, the present invention processes the filtrate and the water-containing filter residue separated from the solid ash water separately, obtains recycled water and crystallized salt from the filtrate, and obtains recycled metal from the water-containing filter residue. On the one hand, the metal in the heavy oil raw material can be recovered and the quality of the recovered metal is high, which solves the problem that the metal in the gasification ash cannot be recovered or the recovery cost is too high, and avoids environmental pollution caused by direct combustion or landfill, wherein the total metal recovery rate is maintained at more than 90%; on the other hand, the salt and water in the aqueous phase of the system can be recovered, which can improve the utilization rate of heavy oil resources and reduce the use of external water, further improving the competitiveness of heavy oil gasification technology, wherein the recovery rate of crystallized salt is not less than 90% and the recovery rate of recycled water is not less than 75%. In addition, by adopting the method disclosed in the present invention, high-quality crystalline salt and recycled water can be obtained, which can not only achieve near-zero discharge of high-salt wastewater, but also improve the efficient recycling of salt and water, thereby reducing energy consumption and harm to the environment; wherein the obtained crystalline salt includes sodium sulfate crystalline salt that meets the first-class standard of Class I salt in the GB / T 6009-2014 "Industrial Anhydrous Sodium Sulfate" standard and sodium chloride crystalline salt that meets the first-class standard of refined industrial dry salt in the GB / T 5462-2015 "Industrial Salt" standard; and the recycled recycled water does not require secondary treatment or only needs simple treatment to obtain recycled water quality that meets the "Water Quality Standard for Recycled Water for Circulating Cooling Water HG-T3923-2007" standard.

[0029] The device used in the gasification unit of the present disclosure includes a gasifier, which is a conventional choice in the field. The gasifier of the present application adopts a quenching scheme, and the upper part of the gasifier is a gasification chamber and the lower part is a quenching chamber. The gasifier and the gasified raw material are injected into the gasifier through a burner. After the gasified raw material is atomized by the burner, the gasified raw material oils collide with each other, and the gasified raw material oils collide with oxygen, water vapor and the gasifier, resulting in violent combustion and gasification reactions. The reaction products and residues flow downward through the washing and cooling pipe into the quenching chamber; the residue leaves the quenching chamber from the slag discharge port, and the gaseous product leaves the quenching chamber from the gaseous product outlet.

[0030] The water vapor can be mixed with the heavy oil raw material, oxygen or both and then introduced into the gasification chamber. Preferably, the water vapor, heavy oil raw material and oxygen are uniformly mixed at the burner and then introduced into the gasification chamber, and the uniformly mixed materials are injected into the gasifier at a high speed at the burner to achieve the purpose of improving the gas-liquid mass transfer coefficient.

[0031] The heavy oil raw material enters from the top of the gasifier, or the heavy oil raw material enters symmetrically from the upper part of the gasifier. The number of burners arranged symmetrically in a single layer is 2-10, and the number of burner layers arranged is 1-6. Furthermore, in order to reduce the erosion of the refractory bricks of the gasifier body by the high-temperature flame of gasification, the raw material preferably enters vertically from the top of the gasifier.

[0032] In this embodiment, the gasification of heavy oil feedstock is a flame-type reaction, and the reaction between hydrocarbons and oxygen is completed instantly. In order to control the reaction temperature in the gasifier, a temperature regulator needs to be introduced, and the temperature regulator is usually water vapor, water or an inert gas, such as carbon dioxide. Water is usually used as a carrier and temperature regulator for solid fuels; water vapor is often used as a temperature regulator for liquid fuels. The introduction of steam into the gasifier can not only act as an oxidant to react with various hydrocarbons, but also act as a buffer furnace to gently inhibit the formation of carbon black. The amount of steam added is generally expressed by the size of the steam-to-oil ratio.

[0033] Among them, since the gasification of heavy oil raw materials is a high-temperature, hydrogen-containing condition, the operating stability of the device is directly related to the gasifier operation cycle and product gas composition. Therefore, it is necessary to accurately control the crude oil feed rate and oxygen feed rate, and at the same time, adjust the steam injection rate in combination with the furnace temperature of the gasifier. The ratio of the oxygen content in the oxygen to the carbon content in the heavy oil raw material is (1-2):1. Since water vapor is introduced into the gasifier, the ratio of the oxygen content in the water vapor to the carbon content in the heavy oil raw material is (1.05-2.5):1.

[0034] The oxygen consumption is 0.8 to 2.0 Nm per 1 kg of heavy oil. 3 .

[0035] The amount of water vapor injected is 300 to 900 kg, preferably 400 to 600 kg, relative to 1 kg of heavy oil.

[0036] The heavy oil raw material disclosed in the present invention is one or more selected from residual oil, deoiled asphalt, deasphalted oil, coal tar, shale oil and crude oil.

[0037] In order to improve the gasification efficiency and increase the content of the product synthesis gas, the present disclosure requires that the purity of oxygen is not less than 99.8% by volume.

[0038] The steam is selected from at least one of low-pressure steam, medium-pressure steam, high-pressure steam and ultra-high-pressure steam. The steam pressure is determined according to the pressure of the gasifier. Generally speaking, superheated steam is usually used to avoid condensation of steam. In addition, a steam buffer tank needs to be set on the steam feed pipeline.

[0039] The conditions of the oxidation reaction in step S1 include: the gasification temperature is 950-1650° C., and the gasification pressure is 0.1 MPaG-10 MPaG; preferably, the gasification temperature is 1200-1450° C., and the preferred gasification pressure is 2.0 MPaG-7.0 MPaG.

[0040] In the above embodiment, the heavy oil raw material interacts with oxygen and water vapor under high temperature and high pressure conditions to decompose into gas molecules such as CO, CO2, H2S, COS, NH3, H2, CH4, etc. The generated gas and ash are cooled by quenching water to obtain saturated crude synthesis gas and ash-containing black water; therefore, the oxidation reaction product after being treated by the gasifier includes crude synthesis gas and ash-containing black water. The gasifier outlet synthesis gas temperature is 200-450℃, pressure is 0.1MPaG-10MPaG, and particle content is less than 2000g / Nm 3 .

[0041] In one embodiment, the first separation treatment described in step S1 of the present disclosure includes: S11, allowing the raw synthesis gas to enter a separation and purification device for separation and purification treatment to obtain the purified synthesis gas and high-pressure solid ash water.

[0042] In this embodiment, in order to purify the saturated raw synthesis gas and remove a small amount of solid particles carried in the raw synthesis gas, the raw synthesis gas needs to be purified in a separation and purification device.

[0043] The separation and purification device at least includes a multi-stage scrubber and a gas-liquid separator. Washing water is injected into each scrubber, and the scrubber is selected from at least one of a venturi scrubber, a venturi scrubber, and a mixer; the washing water is selected from at least one of conversion condensate, high-pressure ash water, desalted water, deoxygenated water, and fresh water; the temperature of the washing water is 100-450°C, and the pressure of the washing water is 0.5-10MPaG. The number of scrubber stages is preferably two, and the amount of washing water injected into the first-stage scrubber and the second-stage scrubber is 5%wt-20%wt of the amount of synthesis gas.

[0044] In this embodiment, in order to purify the raw synthesis gas while reducing equipment investment and land occupation, the present disclosure preferably sets up a two-stage venturi scrubber, and the solid particles in the gas phase react with the injected washing water phase to achieve the purpose of washing the gas and separating the solid particles.

[0045] The working principle of the Venturi scrubber is as follows: by changing the high-speed raw synthesis gas flow and the cross-section of the pipe it flows through, the synthesis gas and the scrubbing water move relative to each other in the high-speed gas flow, thereby achieving the purpose of scrubbing the synthesis gas. Figure 2As shown, the venturi scrubber used in the present invention is mainly composed of three parts, namely, a contraction tube, a throat tube and an expansion tube. After the crude syngas enters the contraction tube from the syngas inlet a1, the flow rate increases, generating a large acceleration. The washing water is fed in from the washing water inlet a2. Because of its heavy mass, the acceleration generated is small. At this time, the washing water and the syngas produce relative motion, so the two have the opportunity to collide and contact, and the injected washing water is atomized. Further, at the venturi throat, the flow rate of the syngas reaches the maximum value. Due to the small cross-section of the pipeline, the syngas and the washing water are compressed, and the movement speed reaches 50-150m / s. The humidity of the syngas reaches saturation, and at the same time, the air film attached to the surface of the solid particles is broken, and the particles collide and condense violently. As the cross-section gradually increases, the air flow velocity decreases, and the pressure rises. Due to the difference in inertial force between the gas, liquid and solid phases, relative motion is generated, realizing the washing of the crude syngas by the washing water, and the syngas after washing enters the subsequent device from the syngas outlet a3. Furthermore, the venturi scrubber used in the present invention is made of metal material or metal composite material with good abrasion resistance and strong impact resistance. The present invention does not specifically limit the material, as long as it meets the mechanical and process performance requirements of the venturi scrubber.

[0046] Among them, a gas-liquid separator tank is provided at the outlet of the first-stage venturi scrubber, and the gas-liquid separator tank is preferably a vertical separation tank. In order to achieve efficient gas-liquid separation, the tank is provided with efficient gas-liquid separation internal components, such as gas-liquid cyclone internal components, cyclone separators or special herringbone tray internal components. According to the requirements of the solid particle concentration of the crude synthesis gas and the system configuration, the tank bottom flow is sent to the downstream facilities and / or to the scrubber. A small amount of tank bottom flow is discharged to the downstream facilities to keep the solid particles in the separation and purification device from accumulating, so as to achieve the purpose of extending the operation cycle.

[0047] In order to further remove a small amount of solid particles carried in the syngas, the syngas at the top of the separation tank is sent to a secondary venturi scrubber, and a scrubber is provided at its outlet. The scrubber is used to further capture particles in the syngas to achieve the goal of purifying the solid particles in the syngas to less than 5mg / Nm 3 The scrubber is provided with gas-liquid contact trays or fillers. In order to avoid solid particles blocking the trays and shortening the operation cycle, the lower part of the scrubber is preferably a herringbone tray, and the upper part of the scrubber can be provided with a float valve and a sieve plate tray. In order to purify the synthesis gas, the scrubber needs to inject at least one washing liquid, which is selected from at least one of conversion condensate, high-pressure gray water, desalted water, deoxygenated water, and fresh water. Conversion condensate, gray water, and deoxygenated water are preferred. In order to maintain the temperature of the synthesis gas, the temperature of the washing liquid is 100-450°C.

[0048] According to the present disclosure, in order to extend the operation cycle of the gasification device, the separator and the scrubber bottom adopt one of a circular head, an elliptical head, and a conical head, preferably a conical head. Furthermore, the angle between the conical surface of the conical head and the horizontal plane is not less than 30°, preferably 45-80°.

[0049] In order to comprehensively utilize resources and energy and further improve the energy efficiency of the scrubbing process, the material at the bottom of the scrubber is sent downstream to separate solid particles and / or to the gasifier as quenching water and / or circulated into the scrubber. In order to ensure that the solid particles in the liquid phase at the bottom of the scrubber are not too high, a small amount of the bottom liquid needs to be discharged to the downstream facilities to extend the operation cycle.

[0050] In one embodiment, step S1 of the present disclosure further includes: S12, allowing the ash-containing black water and the high-pressure solid-containing ash water to enter a gas-liquid separation device for gas-liquid separation to obtain the acid gas, the acid water and the low-pressure solid-containing ash water.

[0051] Among them, the separation level of the gas-liquid separation device is 2-5 levels, and the pressure of the gas-liquid separation device is -0.09 to 3.5MPaG. The effluent at the bottom of the scrubber is sent to a multi-stage solid-liquid separation facility to achieve the purpose of solid-liquid separation and recycling water resources. In this embodiment, the number of stages of the gas-liquid separation device is preferably 3. For example, the 3-stage gas-liquid separation device can be a high-pressure flash tank, a low-pressure flash tank, and a vacuum flash tank. The temperature of the high-temperature flash gas is 150℃-300℃, and the pressure of the high-temperature flash gas is 0.1MPaG-1.5MPaG. Preferably, the number of stages of the gas-liquid separation facility is 3. The temperature of the gray water separated from the bottom of the scrubber is 100-250°C, the particle content is 0.01-1.5%wt, and the pressure is 0.5-3.0MPaG. The preferred black water temperature is 150-250°C, the particle content is 0.1-0.8%wt, and the pressure is 0.5-1.5MPaG; the operating temperature of the low-pressure flash evaporator is 100-250°C, the particle content is 0.01-2.0%wt, and the pressure is 0.1-0.5MPaG. The preferred low-pressure flash evaporator is The operating temperature of the evaporator is 100-200° C., the particle content is 0.015-1.5%wt, and the pressure is 0.1-0.4MPaG; the operating temperature of the vacuum flash evaporator is 50-150° C., the particle content is 0.01-2.0%wt, and the pressure is -0.01-0.1MPaG. The preferred operating temperature of the vacuum flash evaporator is 50-120° C., the particle content is 0.02-1.5%wt, and the pressure is -0.01-0.09MPaG.

[0052] In one embodiment, the method disclosed herein can be used with any heavy oil gasification raw material, and the number of washing stages can be set according to the particle content in the gas at the outlet of the gasifier, and the multi-stage liquid-solid separation facilities can be set according to the composition of the liquid at the bottom of the scrubber. The diversity of the setting methods has the effect of large operational flexibility and flexible adjustment of the hydrogen-carbon ratio of the gasification product. It is suitable for the process of large-scale carbon-containing material gasification to produce synthesis gas.

[0053] In one embodiment, in order to separate solid particles from the ash water and recycle the ash water, the low-pressure solid-containing ash water needs to be sent to the slag-water separation unit for a second separation unit. The device used in the slag-water separation unit includes at least an ash water tank, a filter and a filtrate tank.

[0054] Among them, the gray water tank is a conventional choice in this field, and this application does not make any requirements. In order to better achieve solid-liquid separation, an appropriate amount of flocculant can be added to the pipeline entering the gray water collection tank or in the gray water collection tank to accelerate the flocculation and precipitation of solid particulate matter. In order to achieve the interaction between the flocculant and the solid particles, the gray water collection tank can be equipped with an agitator. The amount of flocculant added is added according to the specific gray water composition; the flocculant is a conventional choice in this technical field.

[0055] The filter is selected from a plate and frame filter, a bag filter, a drum filter, a vacuum filter, a belt filter and a gravity filter. In addition, the type of filter needs to be based on the particle concentration and particle size in the ash water. Preferably, the device used in the slag-water separation unit is a vacuum filter. In order to provide a vacuum environment, a vacuum pumping facility can be set in the system. The present invention does not limit the type of vacuum pumping equipment, as long as it meets the requirements of various vacuum pumping performances. For example, a water ring vacuum pump and / or steam jet vacuum pump is selected, and the moisture content of the filter cake should not exceed 5%wt.

[0056] In order to prevent trace solid particles in the filtrate from settling and clogging pipes and equipment, an appropriate amount of dispersant can be added to the filtrate tank. The amount of dispersant added is based on the specific composition of the filtered gray water. Dispersant is a conventional choice in this technical field.

[0057] In one embodiment, step S3 also includes: S31, allowing the filtrate to enter a homogenization adjustment device for homogenization treatment to obtain a homogenous filtrate; S32, allowing the homogenous filtrate to enter a pretreatment device for pretreatment reaction to obtain a pretreated filtrate; S33, allowing the pretreated filtrate to enter a crystallization salt separation device for crystallization treatment to obtain the mixed material.

[0058] Among them, the pretreatment device includes a coagulation sedimentation tank, an anaerobic homogenization regulating tank, an anaerobic mixing tank, an anaerobic reactor, a pretreatment effluent tank, as well as softening and clarification equipment, a saline sewage homogenization regulating tank, a saline sewage two-stage A / O biochemical tank, a saline sewage secondary sedimentation tank, a saline sewage high-density sedimentation tank, a saline sewage ozone oxidation tank, a saline sewage ozone stabilization tank and a saline sewage aerated biological filter.

[0059] Among them, connecting equipment between devices can be equipped as needed, including but not limited to return sludge pumps. Other equipment, such as sludge thickening tanks, can also be added as needed.

[0060] The crystallization and salt separation device includes one or more of a membrane concentration device, a nanofiltration device, a reverse osmosis device and a salt crystallization device. The flow entering the crystallization and salt separation device is high salt water with a TDS of 30,000-500,000; the main component of the high salt water is Na + 、SO4 2- , Cl - 、CO3 2- 、HCO3 - The crystalline salts separated are mainly sodium sulfate, sodium sulfate decahydrate, sodium chloride, sodium carbonate, sodium bicarbonate, etc.

[0061] Among them, the method of salt crystallization can adopt the process of thermal salt separation and / or frozen crystallization according to the different components of the brine. For sodium chloride crystallization salt, multi-effect evaporation thermal salt separation is usually adopted, and further, 3-5 effects of vacuum evaporation are adopted to obtain industrial salt quality; for sodium sulfate, multi-effect evaporation thermal salt separation can also be adopted, and freezing method can also be adopted to crystallize sodium sulfate and sodium sulfate decahydrate. The present invention does not limit the type of evaporation crystallizer and freezing crystallizer, as long as it meets the requirements of sodium sulfate, sodium chloride, and sodium carbonate crystallization salt.

[0062] Among them, the homogenization adjustment device is a homogenization adjustment tank to remove possible floating oil, colloids and some suspended matter in high-salinity wastewater.

[0063] In this embodiment, by setting up processes such as a homogenizing adjustment device, a pretreatment device and a crystallization salt separation device, sodium sulfate crystal salt that meets the first-class standard of Class I salt in the GB / T 6009-2014 "Industrial Anhydrous Sodium Sulfate" standard and sodium chloride crystal salt that meets the first-class standard of refined industrial dry salt in the GB / T 5462-2015 "Industrial Salt" standard can be directly recovered. The recycled water does not need secondary treatment or only needs simple treatment to obtain recycled water quality that meets the "Water Quality Standard for Recycled Water for Circulating Cooling Water HG-T3923-2007" standard. The present disclosure not only achieves near-zero discharge of high-salt wastewater, but also achieves efficient recycling of salt and water, which is in line with today's green concept of saving and environmental protection.

[0064] In one embodiment, step S3 further includes: S34, allowing the discharged mother liquor to enter a mother liquor concentration device for concentration treatment to obtain a final mother liquor; S35, allowing the final mother liquor to enter a mother liquor drying device for drying treatment to obtain the impure salt solid.

[0065] In this embodiment, in order to ensure the quality of crystallized salt and recycled water, the crystallization salt separation device needs to discharge a small amount of mother liquor. The small amount of mother liquor discharged is a saturated solution. It can also be treated by evaporation crystallization and freezing crystallization, so that part of the salt in the mother liquor is crystallized and precipitated. The quality of the obtained crystallized salt is worse than that of the salt precipitated by the crystallization salt separation device, and is generally treated as a qualified product. The final mother liquor that cannot be treated is sent to the mother liquor drying unit. The mother liquor drying unit can adopt at least one of spray drying, drum drying, rake dryer, and scraper drying. Because the final mother liquor contains a small amount of VOCs, the quality of the crystallized salt after drying is poor, and it is generally treated as solid waste. The amount of solid waste is related to the front-end heavy oil gasification process, heavy oil composition, and filtrate treatment process. Usually the amount of solid waste accounts for 1%-15% (by weight) of crystallized salt.

[0066] In one embodiment, step S4 also includes: S41, allowing the water-containing filter residue to enter a filter residue drying device for filter residue drying treatment to obtain a dry filter residue; S42, allowing the dry filter residue to enter an incineration device for incineration treatment to obtain an incineration product and incineration flue gas; S43, allowing the incineration product to enter a metal recovery device for metal recovery treatment to obtain the recovered metal; S44, allowing the incineration flue gas to enter the mother liquor drying device as a heat medium to participate in the drying treatment.

[0067] In this embodiment, in order to recover the metal in the filter residue, the filter residue obtained by the slag water filtration unit is further processed, and the water content in the separated filter residue is about 3-5% by weight. In order to reduce the energy consumption of the incineration unit, the water-containing filter residue is processed in a filter residue drying device to maintain the moisture content in the dried filter residue below 0.5% by weight. The commonly used filter residue drying device adopts at least one of filter pressing, heating evaporation or natural drying, preferably filter pressing and heating evaporation; the obtained dry filter residue is sent to the incineration device. The function of the incineration device is to remove flammable carbon, sulfur, hydrogen and other components in the filter residue to obtain ash rich in metal molybdenum, vanadium and nickel.

[0068] Wherein, the incineration device can adopt at least one of blank roasting and sodium method roasting; when the sodium method roasting is adopted, the sodium salts such as sodium chloride and sodium sulfate separated by the crystallization salt separation device can be adopted.

[0069] Among them, when the mother liquor drying unit adopts spray drying, the high-temperature flue gas generated by the incineration unit can be used as the heat source. On the one hand, it can achieve the purpose of drying the final mother liquor, and on the other hand, it can make full use of the heat source generated by the incineration unit to enhance the competitiveness of the entire technology.

[0070] Wherein, the operating conditions of the incineration device are: the incineration temperature is 500-1300°C, and the incineration time is 0.5-5.0h.

[0071] In one embodiment, the metal recovery treatment includes mechanical crushing treatment, leaching treatment and precipitation treatment; the conditions of the leaching treatment include: leaching temperature of 50-150°C, leaching time of 1.0-10h, and leaching solution including leaching acid and / or leaching alkali solution; the conditions of the precipitation treatment include: precipitation temperature of 30-100°C, precipitation time of 0.5-10h, and precipitation solution including precipitation acid and / or precipitation alkali solution; the leaching acid and the precipitation acid are each independently selected from one or more of hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, hypochlorous acid, hydrofluoric acid and carbonic acid; the leaching alkali solution and the precipitation alkali solution are each independently selected from one or more of sodium hydroxide, potassium hydroxide and sodium carbonate.

[0072] Wherein, the pH value of the precipitation solution is 7.5-14.

[0073] Among them, the process flow of metal recovery and treatment can be flexibly adjusted according to the composition of the incineration product generated by the incineration device. For example, in a specific embodiment of the present disclosure, the dried filter residue of the present disclosure is roasted at 500-1300°C for 0.5-5h to remove the flammable carbon, sulfur, hydrogen and other components in the filter residue to obtain ash rich in metal molybdenum, vanadium and nickel. Take an appropriate amount of sodium hydroxide solution and add it to the roasted ash, leaching for 1-10h, the leaching temperature is controlled at 50-150°C, and after the leaching is completed, it is washed and filtered for many times to obtain a nickel-containing residue and a solution rich in molybdenum and vanadium. Add an appropriate amount of sulfuric acid solution to the nickel-containing metal residue to leach nickel metal, leaching for 1-10h, the leaching temperature is controlled at 50-150°C, and after the leaching is completed, it is washed and filtered for many times, and finally the filtrate is neutralized with sodium hydroxide until the precipitation no longer increases, and nickel is precipitated as nickel hydroxide. Add an appropriate amount of ammonium chloride to the solution rich in molybdenum and vanadium, and the vanadium metal is precipitated as ammonium vanadate. After washing and filtering, an ammonium vanadate precipitate and a molybdenum solution are obtained. Hydrochloric acid is added to the molybdenum solution, and the molybdenum metal is precipitated as molybdic acid, and solid ammonium molybdate is obtained after washing and separation. According to calculation, the weight recovery rate of molybdenum is not less than 92%, the weight recovery rate of vanadium is not less than 93%, and the weight recovery rate of nickel is not less than 92.5%.

[0074] In one embodiment, the method further comprises: S5, allowing the purified synthesis gas to enter a synthesis gas device; S6, allowing the acid gas to enter a sulfur recovery unit to recover sulfur; S7, allowing the acid water to enter an acid water stripping unit for stripping treatment to obtain second recycled water.

[0075] In order to recover the sulfur resources in the acidic water, a stripping tower and a liquid separation tank on the top of the stripping tower are set at the acidic water outlet. The acidic gas containing H2S and COS separated from the top of the tank is sent to the sulfuric acid recovery device, and the acidic water at the bottom of the tank is pumped to the acidic water stripping device, and the water is reused after treatment.

[0076] In a further embodiment, in order to maintain the salt content of the gasification system and the balance of hardness, silicon, ammonia nitrogen, etc. in each circulating water, a small amount of ash water needs to be discharged to the sewage treatment plant, and a small amount of fresh water is added to maintain the system balance.

[0077] In one embodiment, if Figure 1 As shown, the methods for resource utilization of heavy oil include:

[0078] S1. Allow oxygen, water vapor and heavy oil feedstock to enter the gasification unit for oxidation reaction to obtain crude synthesis gas and ash-containing black water; allow the crude synthesis gas to enter the separation and purification device for separation and purification to obtain the purified synthesis gas 20 and high-pressure solid-containing ash water; allow the ash-containing black water and the high-pressure solid-containing ash water to enter the gas-liquid separation device for gas-liquid separation to obtain acid gas 1, acid water 3 and low-pressure solid-containing ash water 2.

[0079] S2, allowing the low-pressure solid ash-containing water 2 to enter a slag-water separation unit for a second separation treatment to obtain a filtrate 4 and a water-containing filter residue 12;

[0080] S3, allowing the filtrate 4 to enter a homogenizing adjustment device for homogenization treatment to obtain a homogenous filtrate 5; allowing the homogenous filtrate 5 to enter a pretreatment device for pretreatment reaction to obtain a pretreatment filtrate 6; allowing the pretreatment filtrate 6 to enter a crystallization salt separation device for crystallization treatment to obtain the mixed material; allowing the mixed material to enter a crystallization separation unit for a third separation to obtain a first recycled water 7, crystallized salt 8 and an effluent mother liquor 9; allowing the effluent mother liquor 9 to enter a mother liquor concentrating device for concentration treatment to obtain a final mother liquor 10; allowing the final mother liquor 10 to enter a mother liquor drying device for drying treatment to obtain a mixed salt solid 11.

[0081] S4, allowing the water-containing filter residue 12 to enter a filter residue drying device for filter residue drying treatment to obtain a dry filter residue 13; allowing the dry filter residue 13 to enter an incineration device for incineration treatment to obtain an incineration product 15 and an incineration flue gas 14; allowing the incineration product 15 to enter a metal recovery device for metal recovery treatment to obtain recovered metal 16 and ash 17; allowing the incineration flue gas 14 to enter the mother liquor drying device to participate in the drying treatment;

[0082] S5, allowing the purified synthesis gas 20 to enter the synthesis gas device;

[0083] S6, allowing the acid gas 1 to enter a sulfur recovery unit to recover sulfur;

[0084] S7, allowing the acidic water 3 to enter the acidic water stripping unit for stripping treatment to obtain second recycled water.

[0085] The second aspect of the present disclosure is a system for heavy oil resource utilization using the method shown in the first aspect, the system comprising a gasification unit, a first separation unit, a slag-water separation unit, a crystallized salt unit, a crystallized separation unit, a final mother liquor treatment unit and a metal recovery unit: the gasification unit comprises an oxygen inlet, a water vapor inlet, a heavy oil feedstock inlet and an oxidation reaction product outlet; the first separation unit comprises an oxidation reaction product inlet, a purified synthesis gas outlet, an acid gas outlet, an acid water outlet and a low-pressure solid ash water outlet; the slag-water separation unit comprises a low-pressure solid ash water inlet, a filtrate outlet and a water-containing slag outlet; the crystallized salt unit comprises a filtrate inlet and a mixed material outlet; the crystallized separation unit comprises a mixed material inlet, a first recycled water outlet, a crystallized salt outlet and an external mother liquor outlet; the final mother liquor treatment unit comprises an external mother liquor inlet and a miscellaneous salt solid outlet; the metal recovery unit comprises a water-containing slag inlet and a recovered metal outlet; the oxidation reaction product of the gasification unit The material outlet is connected with the oxidation reaction product inlet of the first separation unit, so that the oxidation product can undergo a first separation; the low-pressure solid-containing ash water outlet of the first separation unit is connected with the low-pressure solid-containing ash water inlet of the slag-water separation unit, so that the low-pressure solid-containing waste water generated by the separation can enter the slag-water separation unit for separation; the filtrate outlet of the slag-water separation unit is connected with the filtrate inlet of the crystallization salt unit, so that the filtrate can enter the crystallization salt unit for treatment; the mixed material outlet of the crystallization salt unit is connected with the mixed material inlet of the crystallization separation unit, so that the crystallized mixed material can enter the crystallization separation unit for separation; the external mother liquor outlet of the crystallization separation unit is connected with the external mother liquor inlet of the final mother liquor treatment unit, so that the external mother liquor can enter the mother liquor treatment unit for treatment; the aqueous filter residue outlet of the slag-water separation unit is connected with the aqueous filter residue inlet of the metal recovery unit, so that the aqueous filter residue can be processed by the metal recovery unit to recover metal.

[0086] The present disclosure is further illustrated by the following examples, but the present disclosure is not limited thereto. The properties of the heavy oil feedstock are shown in Table 1.

[0087] Table 1 Properties of heavy oil feedstock

[0088]

[0089]

[0090] Example 1

[0091] Heavy oil resource utilization system Figure 1The system shown includes a gasification unit 101, a sulfur recovery unit 102, an acid water stripping unit 103, a slag-water separation unit 104, a homogenization adjustment device 105, a pretreatment device 106, a crystallization and salt separation device 107, a mother liquor concentration device 108, a mother liquor drying device 109, a filter residue drying device 110, an incineration device 111 and a metal recovery device 112.

[0092] Methods for recycling heavy oil include:

[0093] S1. Allow oxygen, water vapor and heavy oil raw materials to enter the gasifier for oxidation reaction to obtain crude synthesis gas and ash-containing black water; wherein the purity of oxygen is 99.9% and the pressure is 8.1MPaG; the water vapor is ultra-high pressure steam, the temperature is 350℃ and the pressure is 8.5MPaG; the pressure of the gasifier is 6.5MPaG, the gasification temperature is 1350℃, the synthesis gas temperature at the outlet of the gasifier is 255℃, the pressure is 6.5MPaG, and the solid particle content is 600g / Nm 3 .

[0094] The crude synthesis gas is allowed to enter the separation and purification device for separation and purification treatment to obtain the purified synthesis gas 20 and high-pressure solid ash-containing water; 70% of the high-pressure solid ash-containing water is pumped at the bottom of the scrubber and then sent back to the gasifier as quenching water to return to the gasifier. The separation and purification treatment is a two-stage gas scrubbing, both of which use a venturi scrubber. A gas-liquid separation tank is set between the two-stage scrubbers. The gas phase of the first-stage separation tank is scrubbed by the second-stage venturi scrubber and then sent to the scrubber, and the liquid phase is directly sent to the scrubber. The purified synthesis gas is obtained at the top of the scrubber, and the high-pressure solid ash-containing water is obtained at the bottom; the temperature of the scrubbing water is 180°C, and the pressure of the scrubbing water is 8.1MPaG.

[0095] The ash-containing black water and 30% of high-pressure solid ash-containing water enter the gas-liquid separation device for gas-liquid separation to obtain acid gas 1, acid water 3 and low-pressure solid ash-containing water 2. Among them, the gas-liquid separation device is a three-stage gas-liquid separator (high-pressure flash tank, low-pressure flash tank, vacuum flash tank); the high-pressure flash tank temperature is 185°C and the pressure is 1.0MPaG, the low-pressure flash tank temperature is 136°C and the pressure is 0.21MPaG, and the vacuum flash tank temperature is 80°C and the pressure is -0.045MPaG. The scrubber is equipped with gas-liquid cyclone separation internals. In addition, the bottom of the scrubber adopts a conical design, and the angle between the bottom cone and the horizontal plane is 60°.

[0096] S2, allowing the low-pressure solid-containing ash water 2 to enter the ash water tank and mix with a proper amount of flocculant PAM, and then enter the plate and frame filter for filtration to obtain a filtrate 4 and a water-containing filter residue 12; allowing the filtrate 4 to enter the ash water tank and mix with a proper amount of sodium tripolyphosphate.

[0097] S3, the filtrate 4 in the filtrate tank is sequentially fed into the homogenization adjustment tank to obtain a homogenized filtrate 5. The homogenized filtrate 5 is fed into a high-density clarification tank to remove the sludge in the water and soften it to obtain a clarified liquid and a first reflux liquid containing a small amount of sludge. The high-density clarification tank has a clarified liquid outlet at the top and a reflux liquid outlet at the bottom. The first reflux liquid containing a small amount of sludge is partially fed back to the homogenization adjustment tank for further homogenization adjustment treatment, and the remaining sludge is dehydrated and dried. The clarified liquid enters the ozone catalytic oxidation device and the aerated biological filter to remove part of SS, COD, and BOD, and then enters the sand filter and the submerged ultrafiltration device in sequence for filtration and purification to remove suspended matter and intercept a part of macromolecular organic matter. The treated feed liquid enters the ion exchange device in sequence to further concentrate to obtain a first pre-treated liquid and a second reflux liquid refluxed to the submerged ultrafiltration device. The first pre-treated liquid enters the first reverse osmosis device for concentration to obtain a first reverse osmosis treated liquid and a second reflux liquid recovered to the first reverse osmosis device. The first recovered liquid in the reuse water tank and the first reverse osmosis treatment liquid are pressurized to 0.85MPaG and then enter the raw concentrated water tank and the silicon removal and hardness removal device in turn to remove SiO2 and further soften, and then enter the advanced oxidation / COD removal device to obtain the third reflux liquid and the COD removal treatment liquid treated to the target water quality, wherein the third reflux liquid is refluxed to the silicon removal and hardness removal device, and the COD removal treatment liquid enters the decarbonization tower and the ultrafiltration device in turn, and the second pretreatment liquid and the fourth reflux liquid are obtained from the ultrafiltration device. The second pretreatment liquid is pressurized to 1.5MPaG and then sent to the nanofiltration device for nanofiltration separation treatment to obtain nanofiltration concentrated water and nanofiltration produced water. The nanofiltration concentrated water passes through the nanofiltration concentrated water pretreatment unit to remove possible NH3-N substances and then enters the sodium sulfate crystallizer and the sodium chloride crystallizer for four-effect vacuum evaporation crystallization treatment to obtain sodium sulfate crystalline salt, sodium chloride crystalline salt and the first reuse water 7. In order to ensure the quality of the crystallized salt, part of the mother liquor needs to be discharged, and the mother liquor enters the next stage of vacuum evaporation to obtain qualified sodium sulfate and sodium chloride by-products. The final mother liquor that cannot be processed by the final vacuum evaporation is sent to the mother liquor drying unit. The solid salt 11 obtained by drying is treated as solid waste, and the amount of solid waste is 5.5% of the weight of the crystallized salt.

[0098] S4, allowing the water-containing filter residue 12 to enter a filter residue drying device for filter residue drying treatment to obtain a dry filter residue 13 with a moisture content of 0.3% by weight; allowing the dry filter residue 13 to enter an incineration device for roasting at 850° C. for 4.5 hours to obtain an incineration product 15 and an incineration flue gas 14; the incineration product 15 is an ash rich in metal molybdenum, vanadium, and nickel; allowing the incineration flue gas 14 to enter the mother liquor drying device as a heat source for the drying treatment;

[0099] Take an appropriate amount of sodium hydroxide solution and add it to the incineration product 15, leaching for 5 hours, the leaching temperature is controlled at 90°C, and after the leaching is completed, after multiple washing and filtering, a nickel-containing residue and a solution rich in molybdenum and vanadium are obtained. Add an appropriate amount of sulfuric acid solution to the nickel-containing metal residue to extract nickel metal, leaching for 4.5 hours, and the leaching temperature is controlled at 90°C. After the leaching is completed, it is washed and filtered multiple times, and finally the filtrate is neutralized with sodium hydroxide until the precipitation no longer increases, and nickel is precipitated as nickel hydroxide. Add an appropriate amount of ammonium chloride to the solution rich in molybdenum and vanadium, and the vanadium metal is precipitated as ammonium vanadate. After washing and filtering, an ammonium vanadate precipitate and a molybdenum solution are obtained. Add hydrochloric acid to the molybdenum solution, and the molybdenum metal is precipitated as molybdic acid. After washing and separation, solid ammonium molybdate is obtained. After calculation, the weight recovery rate of molybdenum is 92.5%, the weight recovery rate of vanadium is 94.6%, and the weight recovery rate of nickel is 95.5%.

[0100] S5, allowing the purified synthesis gas 20 to enter the synthesis gas device;

[0101] S6, allowing the acid gas 1 to enter a sulfur recovery unit to recover sulfur;

[0102] S7, allowing the acidic water 3 to enter the acidic water stripping unit for stripping treatment to obtain second recycled water.

[0103] The composition of the purified syngas is shown in Table 2, the process parameters of the oxidation reaction are shown in Table 3, and the parameters of the crystallized salt product and recycled water are listed in Table 4.

[0104] The stable operation period of the device in this embodiment is 350 days.

[0105] Example 2

[0106] The system and method for resource utilization of heavy oil are the same as those in Example 1, except that the filter residue is roasted by the sodium method, and the sodium chloride salt obtained by the crystallization salt unit is used. The roasting temperature is 600°C, and the roasting time is 4.5h. The flammable carbon, sulfur, hydrogen and other components in the filter residue are removed to obtain ash rich in metals such as molybdenum, vanadium and nickel. The high-temperature flue gas generated by incineration is also sent to the mother liquor drying unit as a heat source for final mother liquor drying. Take an appropriate amount of aqueous solution and add it to the roasted ash, leaching for 3.5h, the leaching temperature is controlled at 95°C, and after the leaching is completed, it is washed and filtered many times to obtain a nickel-containing residue and a solution rich in molybdenum and vanadium. The nickel-containing metal residue is added with an appropriate amount of sulfuric acid solution to leach nickel metal, leaching for 4.0h, the leaching temperature is controlled at 90°C, and after the leaching is completed, it is washed and filtered many times, and finally the filtrate is neutralized with sodium hydroxide until the precipitation no longer increases, and nickel is precipitated as nickel hydroxide. An appropriate amount of ammonium chloride is added to the solution rich in molybdenum and vanadium, and the vanadium metal is precipitated as ammonium vanadate. After washing and filtering, the ammonium vanadate precipitate and molybdenum solution are obtained. Hydrochloric acid is added to the molybdenum solution, and the molybdenum metal is precipitated as molybdic acid. After washing and separation, solid ammonium molybdate is obtained. After calculation, the weight recovery rate of molybdenum is 95.5%, the weight recovery rate of vanadium is 94.8%, and the weight recovery rate of nickel is 93.8%.

[0107] The composition of the purified synthesis gas, the oxidation reaction process parameters, and the crystallized salt product and recycled water parameters are consistent with those in Example 1.

[0108] The stable operation period of the device in this embodiment is 380 days.

[0109] Comparative Example 1

[0110] The existing technology is used to recycle heavy oil. It includes: gasification unit, separation unit, and high brine treatment unit. According to the heavy oil composition given in Table 1, the solid content of the purified synthesis gas obtained after gasification and separation is 150mg / Nm 3 . The specific oxygen consumption is 385, and the steam consumption is 568kg / ton of heavy oil. The filtrate obtained after flash evaporation of the generated black water is filtered to obtain gasification waste residue, which is landfilled. The discharged high-salt wastewater is processed through a high-salt water treatment unit to obtain mixed salt with a water content of 15% (weight). The recycled water is further treated by biochemical treatment, ozone oxidation, etc. and used as circulating water replenishment. The recycled water rate is 35%. The operating cycle of the system is only 70 days, and the gasification unit and the high-salt water unit need to be stopped for inspection and maintenance.

[0111] Table 2 Purified syngas composition

[0112] Gas composition unit Dry basis, numerical <![CDATA[H2]]> Vol% 43.10 CO Vol% 50.60 <![CDATA[CO2]]> Vol% 4.06 <![CDATA[N2]]> Vol% 0.35 <![CDATA[H2S]]> Vol% 1.65 COS Vol% 0.03 Ar Vol% 0.09 HCN Vol% 0.001 <![CDATA[NH3]]> Vol% 0.006 <![CDATA[CH4]]> Vol% 0.113 Solid content <![CDATA[mg / Nm 3 ]]> 4.5

[0113] Table 3 Oxidation reaction process indicators

[0114] matter unit Numeric Syngas Vol%, dry basis 93.70 Synthesis gas yield <![CDATA[Nm 3 / kg raw material]]> 2.125 Conversion rate of heavy oil feedstock ％ 98.6 <![CDATA[CH4 content]]> ppm, dry basis 1185 Specific oxygen consumption <![CDATA[Nm 3 O2 / 1000Nm 3 CO+H2]]> 325.6 O / C Ratio 1.15 Oxygen consumption <![CDATA[Nm 3 O2 / kg heavy oil]]> 1.21 Steam consumption Steam / Heavy Oil 550

[0115] Table 4 Crystallized salt product and recycled water parameters

[0116]

[0117]

[0118] It can be seen from the data in the table that, by comparing the data in Examples 1 to 2 with the data in Comparative Example 1, the method disclosed in the present invention can, on the one hand, recover metals in heavy oil raw materials with high quality, thereby solving the problem that metals in gasification ash cannot be recovered or the recovery cost is too high, and avoiding environmental pollution caused by direct combustion or landfilling; on the other hand, it can recover salt and water in the aqueous phase of the system, thereby improving the utilization rate of heavy oil resources and reducing the amount of external water use, further improving the competitiveness of heavy oil gasification technology; on the other hand, it can obtain high-quality crystalline salt and recycled water, which can not only achieve near-zero discharge of high-salt wastewater, but also improve the efficient recovery and utilization of salt and water, thereby reducing energy consumption and harm to the environment.

[0119] The preferred embodiments of the present disclosure are described in detail above in conjunction with the accompanying drawings; however, the present disclosure is not limited to the specific details in the above embodiments. Within the technical concept of the present disclosure, a variety of simple modifications can be made to the technical solution of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.

[0120] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present disclosure will not further describe various possible combinations.

[0121] In addition, various embodiments of the present disclosure may be arbitrarily combined, and as long as they do not violate the concept of the present disclosure, they should also be regarded as the contents disclosed by the present disclosure.

Claims

1. A method for resource utilization of heavy oil, characterized in that: The method includes: S1, oxygen, water vapor and heavy oil feedstock are introduced into a gasification unit for oxidation reaction, and then cooled by quenching water to obtain an oxidation reaction product including crude synthesis gas and ash-containing black water; the oxidation reaction product is subjected to a first separation treatment to obtain purified synthesis gas, acid gas, acid water and low-pressure solid ash-containing water; S2, allowing the low-pressure solid ash-containing water to enter a slag-water separation unit for a second separation treatment to obtain a filtrate and a water-containing filter residue; S3, allowing the filtrate to enter the crystallization salt unit for crystallization treatment to obtain the first recycled water, crystallized salt and effluent mother liquor; allowing the effluent mother liquor to enter the final mother liquor treatment unit for drying treatment to obtain impure salt solid; S4, allowing the water-containing filter residue to enter a metal recovery unit for metal recovery treatment to obtain recovered metal.

2. The method according to claim 1, characterized in that: The heavy oil raw material is selected from one or more of residual oil, deoiled asphalt, deasphalted oil, coal tar, shale oil and crude oil; The purity of the oxygen is above 99.8% by volume; The water vapor is selected from one or more of low-pressure steam, medium-pressure steam, high-pressure steam and ultra-high-pressure steam.

3. The method according to claim 1, characterized in that The first separation process described in step S1 includes: S11, allowing the crude synthesis gas to enter a separation and purification device for separation and purification treatment to obtain the purified synthesis gas and high-pressure solid ash-containing water; S12, allowing the ash-containing black water and the high-pressure solid-containing ash water to enter a gas-liquid separation device for gas-liquid separation to obtain the acid gas, the acid water and the low-pressure solid-containing ash water.

4. The method according to claim 1, characterized in that: The oxidation reaction conditions in step S1 include: the oxidation reaction is carried out in a gasifier at a gasification temperature of 950-1650°C, a gasifier pressure of 0.1MPaG-10MPaG, a crude synthesis gas temperature of 200-450°C, a pressure of 0.1MPaG-10MPaG, and a particle content of less than 2000g / Nm 3 The solid particle content in the purified synthesis gas is less than 5 mg / Nm 3 .

5. The method according to claim 1, characterized in that: Step S3 also includes: S31, allowing the filtrate to enter a homogenizing adjustment device for homogenization treatment to obtain a homogenous filtrate; S32, allowing the homogenized filtrate to enter a pretreatment device for pretreatment reaction to obtain a pretreated filtrate; S33, allowing the pre-treated filtrate to enter a crystallization salt separation device for the crystallization treatment; the crystallization salt separation device includes one or more of a membrane concentration device, a nanofiltration device, a reverse osmosis device and a salt crystallization device.

6. The method according to claim 1, characterized in that Step S3 also includes: S34, allowing the effluent mother liquor to enter a mother liquor concentrating device for concentration treatment to obtain a final mother liquor; S35, allowing the final mother liquor to enter a mother liquor drying device for drying treatment to obtain the impure salt solid.

7. The method according to claim 6, characterized in that Step S4 also includes: S41, allowing the water-containing filter residue to enter a filter residue drying device for filter residue drying treatment to obtain a dry filter residue; S42, allowing the dried filter residue to enter an incineration device for incineration treatment to obtain an incineration product and incineration flue gas; S43, allowing the incineration product to enter a metal recovery device for metal recovery treatment to obtain the recovered metal; S44, allowing the incineration flue gas to enter the mother liquor drying device as a heat medium to participate in the drying process.

8. The method according to claim 7, characterized in that The metal recovery process includes mechanical crushing, leaching and precipitation; The leaching treatment conditions include: leaching temperature of 50-150°C, leaching time of 1.0-10h, and leaching solution including leaching acid solution and / or leaching alkali solution; The conditions of the precipitation treatment include: precipitation temperature of 30 to 100° C., precipitation time of 0.5 to 10 h, and precipitation solution including precipitation acid and / or precipitation alkali solution; The leaching acid solution and the precipitation acid solution are independently selected from one or more of hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, hypochlorous acid, hydrofluoric acid and carbonic acid; Each group of the leaching alkali solution and the precipitation alkali solution is independently selected from one or more of sodium hydroxide, potassium hydroxide and sodium carbonate.

9. The method according to claim 1, characterized in that: The method further includes: S5, allowing the purified synthesis gas to enter a synthesis gas device; S6, allowing the acid gas to enter a sulfur recovery unit to recover sulfur; S7, allowing the acidic water to enter the acidic water stripping unit for stripping treatment to obtain second recycled water.

10. A system for heavy oil resource utilization using the method according to any one of claims 1 to 9, characterized in that: The system comprises a gasification unit (101), a first separation unit, a slag-water separation unit (104), a crystallization salt unit, a crystallization separation unit, a final mother liquor treatment unit and a metal recovery unit: The gasification unit (101) comprises an oxygen inlet, a water vapor inlet, a heavy oil feedstock inlet and an oxidation reaction product outlet; The first separation unit comprises an oxidation reaction product inlet, a purified synthesis gas outlet, an acid gas outlet, an acid water outlet and a low-pressure solid ash-containing water outlet; The slag-water separation unit (104) comprises a low-pressure solid ash water inlet, a filtrate outlet and a water-containing filter residue outlet; The crystallized salt unit comprises a filtrate inlet and a mixed material outlet; The crystallization separation unit comprises a mixed material inlet, a first recycled water outlet, a crystallized salt outlet and an external mother liquor outlet; The final mother liquor treatment unit comprises an external mother liquor inlet and a miscellaneous salt solid outlet; The metal recovery unit comprises an inlet for water-containing filter residue and an outlet for recovered metal; The oxidation reaction product outlet of the gasification unit (101) is connected to the oxidation reaction product inlet of the first separation unit; the low-pressure solid ash water outlet of the first separation unit is connected to the low-pressure solid ash water inlet of the slag-water separation unit (104); the filtrate outlet of the slag-water separation unit (104) is connected to the filtrate inlet of the crystallization salt unit; the mixed material outlet of the crystallization salt unit is connected to the mixed material inlet of the crystallization separation unit; the external mother liquor outlet of the crystallization separation unit is connected to the external mother liquor inlet of the final mother liquor treatment unit; the water-containing filter residue outlet of the slag-water separation unit (104) is connected to the water-containing filter residue inlet of the metal recovery unit.

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