Multifunctional system for subcritical hydrothermal modification oil recovery and supercritical water oxidation harmless treatment of oil-containing waste and treatment method

Abstract

The invention relates to a multifunctional system for subcritical hydrothermal modification oil recovery and supercritical water oxidation harmless treatment of oily waste. The multifunctional system comprises a material tank, a material pump, a heater, a reactor, a three-phase separator and the like. Materials are fed into the first-stage heater from the material tank through the material pump to be heated to 350 DEG C, enter the second-stage heater to be subjected to heat compensation and then enter the reactor, and waste oil recovery and modification are carried out under the subcritical hydrothermal condition. The modified oil product is separated and stored, and the waste liquid which is not completely decomposed is further treated through an oxidation process. Under the supercritical water oxidation working condition, the waste liquid and an oxidizing agent enter a reactor together for thorough oxidation reaction, organic pollutants are converted into carbon dioxide and water, and finally harmless discharge is achieved. The system further comprises a cooling water system and a temperature control system, stable operation of all devices is guaranteed, and potential safety hazards caused by too high or too low temperature are avoided. And through an ultrasonic cavitation technology, the reaction efficiency and the waste treatment effect are further improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of waste treatment, and particularly relates to a multi-functional system for subcritical hydrothermal upgrading and oil recovery and supercritical water oxidation for harmless treatment of oil-containing waste, and also relates to a method for subcritical hydrothermal upgrading and oil recovery and supercritical water oxidation for harmless treatment of oil-containing waste. Background Art

[0002] With the continuous advancement of the industrialization process, the generation amount of oil-containing waste increases year by year. These wastes include oil sludge in the process of oilfield exploitation, chemical waste, floating slag and wastewater generated by refineries, etc. If the oil-containing waste is not properly treated, it is easy to cause serious environmental pollution. Especially, the diffusion of oil pollution in water not only affects water quality, but also may threaten the survival of aquatic organisms. Therefore, how to efficiently, safely and environmentally treat these oil-containing wastes has become an urgent problem to be solved in the current environmental protection field.

[0003] At present, the treatment methods of oil-containing waste mainly include physical methods, chemical methods and biological methods, etc. Physical methods include technologies such as centrifugal separation and membrane filtration, but their treatment effects on low-concentration waste oil are not good, and often require a large amount of energy consumption. Chemical methods separate oil and water by using solvents or catalysts, but there may be problems such as difficult solvent recovery and secondary pollution. Biological methods degrade oil-containing waste through microorganisms, but the treatment cycle is long and the effect is limited.

[0004] In recent years, hydrothermal technology, as an efficient and green waste treatment technology, has received extensive attention. Especially the subcritical hydrothermal upgrading technology can effectively decompose the organic matter in oil-containing waste through the high-temperature and high-pressure characteristics of subcritical water, extract and convert waste oil into high-value oil products. The supercritical water oxidation technology uses the strong oxidizing property of supercritical water to quickly oxidize organic pollutants into carbon dioxide and water to achieve the purpose of harmless discharge.

[0005] Although hydrothermal technology has been applied in the field of waste treatment to a certain extent, the existing technologies usually have problems such as unstable treatment effects, complex equipment design and low energy efficiency. Summary of the Invention

[0006] The first object of the present invention is to provide a multi-functional system for subcritical hydrothermal upgrading and oil recovery and supercritical water oxidation for harmless treatment of oil-containing waste, so as to solve the problem that the existing technology cannot efficiently realize the resource utilization and harmless treatment of oil-containing waste.

[0007] To achieve the above object, the technical solution adopted by the present invention is: a multifunctional system for subcritical hydrothermal upgrading of oil-containing waste to recover oil and supercritical water oxidation for harmless treatment, including a material tank, a reactor, a cooler, a three-phase separator and a cooling water tank; the discharge port of the material tank is sequentially connected to the inlet of the reactor through a material pump, a primary heater and a secondary heater, the reactor is respectively connected to the inlet of the cooler through a liquefaction outlet valve and an oxidation outlet valve, the outlet of the cooler is connected to the inlet of the three-phase separator through a back pressure valve, the cooling water tank is connected with a cooling water pump, and the cooling water pump is respectively communicated with the cavities in the inner walls of the reactor and the cooler through a first cooling water reactor inlet valve and a second cooling water reactor inlet valve. The cavity of the cooler is respectively connected with a material tank preheating inlet valve and a cooling water bypass valve. The material tank preheating inlet valve is communicated with the cavity in the inner wall of the material tank, the cavity of the reactor is connected with a cooling water reactor outlet valve, and the cooling water reactor outlet valve is respectively connected with the material tank preheating inlet valve and the cooling water bypass valve.

[0008] The material tank is interlocked and controlled with the material tank preheating inlet valve through a material tank temperature controller.

[0009] The primary heater is interlocked and controlled with the primary heater through a primary heater temperature controller.

[0010] The secondary heater is interlocked and controlled with the secondary heater through a secondary heater temperature controller.

[0011] The material can be subjected to ultrasonic cavitation treatment through a pre-positioned ultrasonic device after passing through the material pump; the material can be subjected to ultrasonic cavitation treatment through a post-positioned ultrasonic device after passing through the back pressure valve.

[0012] It further includes a combustion improver tank, and the combustion improver tank is sequentially connected to the inlet of the reactor through a combustion improver pump and a combustion improver outlet valve.

[0013] It further includes an oil storage tank and a water storage tank, and the oil storage tank and the water storage tank are respectively connected to the three-phase separator.

[0014] The second object of the present invention is to provide a method for subcritical hydrothermal upgrading of oil-containing waste to recover oil and supercritical water oxidation for harmless treatment, so as to solve the problem in the prior art that the resource utilization and harmless treatment of oil-containing waste cannot be efficiently realized.

[0015] To achieve the above object, the technical solution adopted by the present invention is: a method for subcritical hydrothermal upgrading of oil-containing waste to recover oil and supercritical water oxidation for harmless treatment, specifically: The material is sent from the material tank to the primary heater through the material pump and heated to 350 °C, and then enters the secondary heater for supplementary heating to ensure that it enters the reactor at 350 °C. In the reactor: Under subcritical hydrothermal conditions, waste oil recovery and upgrading are carried out. The upgraded oil products are separated and stored, and the waste liquid that is not completely decomposed is further treated through an oxidation process; Under supercritical water oxidation conditions, the waste liquid and the oxidant enter the reactor together for a complete oxidation reaction to convert organic pollutants into carbon dioxide and water, ultimately achieving harmless discharge.

[0016] The beneficial effects of the present invention are as follows: The multi-functional system for subcritical hydrothermal upgrading of oil-containing waste and supercritical water oxidation for harmless treatment of the present invention combines subcritical hydrothermal upgrading of oil and supercritical water oxidation technologies to design a new type of multi-functional system, effectively solving the deficiencies in the prior art and being able to efficiently recover and harmlessly treat oil-containing waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings described herein are used to provide a further understanding of the present invention and form a part of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings: Figure 1 is a schematic structural diagram of a multi-functional system for subcritical hydrothermal upgrading of oil-containing waste and supercritical water oxidation for harmless treatment of the present invention.

[0018] In the figure, 1. Material tank; 2. Material pump; 3. Primary heater; 4. Secondary heater; 5. Cooler; 6. Three-phase separator; 7. Oil storage tank; 8. Water storage tank; 9. Cooling water tank; 10. Cooling water pump; 11. Oxidation outlet valve; 12. Liquefaction outlet valve; 13. Material tank preheating inlet valve; 14. Cooling water bypass valve; 15. Back pressure valve; 16. Cooling water reactor inlet valve; 17. Cooling water cooler inlet valve; 18. Cooling water reactor outlet valve; 19. Oxidant tank; 20. Oxidant pump; 21. Oxidant outlet valve; 22. Reactor; T01. Material tank temperature controller; T02. Primary heater temperature controller; T03. Secondary heater temperature controller. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0019] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present invention and should not be construed as a limitation to the present invention.

[0020] In the description of the present invention, unless otherwise clearly defined, words such as "set", "installed", and "connected" should be understood in a broad sense. Those skilled in the relevant technical field can reasonably determine the specific meanings of the above words in the present invention in combination with the specific content of the technical solution.

[0021] Example 1 As Figure 1 shown, a multifunctional system for subcritical hydrothermal upgrading and oil recovery and supercritical water oxidation harmless treatment of oil-containing waste of the present invention includes a material tank 1, a reactor 22, a cooler 5, a three-phase separator 6 and a cooling water tank 9.

[0022] The discharge port of the material tank 1 is sequentially connected to the inlet of the reactor 22 through a material pump 2, a primary heater 3 and a secondary heater 4. The reactor 22 is respectively connected to the inlet of the cooler 5 through a liquefaction outlet valve 12 and an oxidation outlet valve 11. The outlet of the cooler 5 is connected to the inlet of the three-phase separator 6 through a back pressure valve 15. The cooling water tank 9 is connected with a cooling water pump 10. The cooling water pump 10 is respectively communicated with the cavities in the inner walls of the reactor 22 and the cooler 5 through a first cooling water reactor inlet valve 16 and a second cooling water reactor inlet valve 17. The cavities of the cooler 5 are respectively connected with a material tank preheating inlet valve 13 and a cooling water bypass valve 14. The material tank preheating inlet valve 13 is communicated with the cavity in the inner wall of the material tank 1. The cavity of the reactor 22 is connected with a cooling water reactor outlet valve 18. The cooling water reactor outlet valve 18 is respectively connected with the material tank preheating inlet valve 13 and the cooling water bypass valve 14.

[0023] Among them: The material tank 1 is used for storing oil-containing waste; the material pump 2 is used for feeding the material from the material tank 1 into the primary heater 3; the primary heater 3 is used for heating the material to 350 °C; the secondary heater 4 is used for supplementary heating of the material and heating the material to 350 °C to 450 °C; the reactor 22 is used for waste oil recovery and upgrading under subcritical hydrothermal conditions, or for harmless treatment of waste liquid under supercritical water oxidation conditions; the liquefaction outlet valve 12 and the oxidation outlet valve 11 are respectively used for controlling the flow direction of the material after liquefaction and oxidation; the three-phase separator 6 is used for separating oil, water and other impurities. The separated oil enters the oil storage tank 7, and the separated water enters the water storage tank 8; the cooler 5 is used for cooling the reacted material; the cooling equipment such as the cooling water tank 9, the cooling water pump 10, the cooling water inlet valve 16, and the cooling water outlet valve 18 is used for cooling the system to ensure the safe operation of the equipment.

[0024] During operation, the material is fed from the material tank 1 into the primary heater 3 by the material pump 2 and heated to 350 °C, then enters the secondary heater 4 for supplementary heating and then enters the reactor 22. In the reactor 22: Waste oil recovery and upgrading are carried out under subcritical hydrothermal conditions. The upgraded oil product is separated and stored, and the uncompletely decomposed waste liquid is further treated through an oxidation process; under supercritical water oxidation conditions, the waste liquid and the oxidant jointly enter the reactor for a complete oxidation reaction to convert organic pollutants into carbon dioxide and water, and finally achieve harmless discharge.

[0025] In addition, the multifunctional system for subcritical hydrothermal upgrading of oil-containing waste to recover oil and supercritical water oxidation for harmless treatment of the present invention further includes a cooling water system and a temperature control system to ensure the stable operation of each device and avoid potential safety hazards caused by excessive or too low temperature. During specific operation, the cooling water in the cooling water tank 9 is introduced into the cavities in the inner walls of the reactor 22 and the cooler 5 respectively through the cooling water pump 10 for cooling.

[0026] Therefore, the present invention provides an efficient, safe and energy-saving solution for treating oil-containing waste, which has broad industrial application prospects.

[0027] Through the ultrasonic cavitation technology, the reaction efficiency and the effect of waste treatment are further improved.

[0028] Example 2 As Figure 1 shown, different from Example 1, in the multifunctional system for subcritical hydrothermal upgrading of oil-containing waste to recover oil and supercritical water oxidation for harmless treatment of the present invention in this Example 2: The material tank 1 is interlocked and controlled with the material tank preheating inlet valve 13 through the material tank temperature controller T01.

[0029] When the material tank preheating inlet valve 13 controls the outflow of cooling water, the temperature of the material tank 1 can be maintained at 80 °C. Example 3 As Figure 1 shown, different from Example 2, in the multifunctional system for subcritical hydrothermal upgrading of oil-containing waste to recover oil and supercritical water oxidation for harmless treatment of the present invention in Example 3: The primary heater 3 is interlocked and controlled with the primary heater 3 through the primary heater temperature controller T02; the secondary heater 4 is interlocked and controlled with the secondary heater 4 through the secondary heater temperature controller T03.

[0030] The primary heater 3 is interlocked and controlled with the primary heater 3 through the primary heater temperature controller T02 to maintain the outlet temperature of the primary heater 3 at 350 °C.

[0031] The secondary heater 4 is interlocked and controlled with the secondary heater 4 through the secondary heater temperature controller T03; to maintain the outlet temperature of the secondary heater 4 at 350 °C under the liquefaction condition and at 450 °C under the supercritical water oxidation condition.

[0032] Example 4 Combined with Figure 1, different from Example 3, in the multifunctional system for subcritical hydrothermal upgrading and oil recovery and supercritical water oxidation harmless treatment of oily waste in Example 4 of the present invention, the material can be subjected to ultrasonic cavitation treatment through a pre - ultrasonic device after passing through the material pump 2 to improve the reaction efficiency; after passing through the back - pressure valve 15, the material can be subjected to ultrasonic cavitation treatment through a post - ultrasonic device to further improve the decomposition efficiency of substances in the reactor 22.

[0033] Example 5 Combined with Figure 1 , different from Example 4, in the multifunctional system for subcritical hydrothermal upgrading and oil recovery and supercritical water oxidation harmless treatment of oily waste in Example 5 of the present invention, it further includes a combustion - aid agent tank 19. The combustion - aid agent tank 19 is sequentially connected to the inlet of the reactor 22 through a combustion - aid agent pump 20 and a combustion - aid agent outlet valve 21.

[0034] During the supercritical water oxidation process, the combustion - aid agent enters the reactor 22 through the combustion - aid agent tank 19, the combustion - aid agent pump 20, and the combustion - aid agent outlet valve 21, and undergoes an oxidation reaction with the organic matter in the waste, oxidizing the organic matter into carbon dioxide and water.

[0035] Example 6 As Figure 1 shown, different from Example 5, in the multifunctional system for subcritical hydrothermal upgrading and oil recovery and supercritical water oxidation harmless treatment of oily waste in Example 6 of the present invention, it further includes an oil storage tank 7 and a water storage tank 8. The oil storage tank 7 and the water storage tank 8 are respectively connected to the three - phase separator 6.

[0036] The oxidized material enters the cooler 5 through the oxidation outlet valve 11, enters the three - phase separator 6 through the back - pressure valve 15, and the separated water enters the water storage tank 8 and is discharged.

[0037] Example 7 As Figure 1 shown, the multifunctional system for subcritical hydrothermal upgrading and oil recovery and supercritical water oxidation harmless treatment of oily waste of the present invention is carried out as follows: The material is sent from the material tank 1 to the first - stage heater 3 through the material pump 2 and heated to 350 °C, and then enters the second - stage heater 4 for supplementary heating to ensure entering the reactor 22 at 350 °C; In the reactor 22: waste oil recovery and upgrading are carried out under subcritical hydrothermal conditions, the upgraded oil products are separated and stored, and the incompletely decomposed waste liquid is further treated through the oxidation process; Under the supercritical water oxidation condition, the waste liquid and the oxidant jointly enter the reactor 22 for a complete oxidation reaction, converting the organic pollutants into carbon dioxide and water, and finally achieving harmless discharge.

[0038] The foregoing description has shown and described several preferred embodiments of the invention. However, as previously mentioned, it should be understood that the invention is not limited to the forms disclosed herein, should not be construed as excluding other embodiments, but can be used in various other combinations, modifications, and environments, and can be altered within the scope of the inventive concept described herein through the above teachings or the skills or knowledge in the relevant field. Any alterations and changes made by those skilled in the art without departing from the spirit and scope of the invention shall fall within the protection scope of the appended claims of the invention.

Claims

1. A multifunctional system for subcritical hydrothermal upgrading of oil-containing waste to recover oil and supercritical water oxidation for harmless treatment, characterized in that, It includes a material tank. The discharge port of the material tank is connected to the inlet of the reactor successively through a material pump, a primary heater, and a secondary heater. The reactor is connected to the inlet of the cooler through a liquefaction outlet valve and an oxidation outlet valve respectively. The outlet of the cooler is connected to the inlet of the three-phase separator through a back pressure valve. A cooling water tank is connected with a cooling water pump. The cooling water pump is communicated with the cavities in the inner walls of the reactor and the cooler respectively through a first cooling water reactor inlet valve and a second cooling water reactor inlet valve. The cavity of the cooler is respectively connected with a material tank preheating inlet valve and a cooling water bypass valve. The material tank preheating inlet valve is communicated with the cavity in the inner wall of the material tank. The cavity of the reactor is connected with a cooling water reactor outlet valve. The cooling water reactor outlet valve is connected with the material tank preheating inlet valve and the cooling water bypass valve respectively.

2. The multifunctional system for subcritical hydrothermal upgrading to recover oil and supercritical water oxidation for harmless treatment of oily waste according to claim 1, wherein The material tank (1) is interlocked and controlled with the material tank preheating inlet valve (13) through a material tank temperature controller (T01).

3. The multifunctional system for subcritical hydrothermal upgrading of oil-containing waste to recover oil and supercritical water oxidation for harmless treatment, according to claim 2, is characterized in that The primary heater (3) is interlocked and controlled with the primary heater (3) through a primary heater temperature controller (T02).

4. The multifunctional system for subcritical hydrothermal upgrading of oil-containing waste to recover oil and supercritical water oxidation for harmless treatment, as claimed in claim 3, is characterized in that, The secondary heater (4) is interlocked and controlled with the secondary heater (4) through a secondary heater temperature controller (T03).

5. The multifunctional system for subcritical hydrothermal upgrading of oil-containing waste to recover oil and supercritical water oxidation for harmless treatment, according to claim 1, is characterized in that, After the material passes through the material pump (2), it can be subjected to ultrasonic cavitation treatment through a preposed ultrasonic device; after the material passes through the back pressure valve (15), it can be subjected to ultrasonic cavitation treatment through a postposed ultrasonic device.

6. The multifunctional system for subcritical hydrothermal upgrading to recover oil and supercritical water oxidation for harmless treatment of oily waste according to claim 1, characterized in that, It also includes a combustion improver tank (19). The combustion improver tank (19) is connected to the inlet of the reactor (22) successively through a combustion improver pump (20) and a combustion improver outlet valve (21).

7. The multifunctional system for subcritical hydrothermal upgrading and oil recovery and supercritical water oxidation harmless treatment of oily waste according to claim 6, characterized in that, It also includes an oil storage tank (7) and a water storage tank (8). The oil storage tank (7) and the water storage tank (8) are respectively connected to the three-phase separator (6).

8. The method for subcritical hydrothermal upgrading and oil recovery and supercritical water oxidation harmless treatment of oily waste is carried out by using the multifunctional system for subcritical hydrothermal upgrading and oil recovery and supercritical water oxidation harmless treatment of oily waste described in any one of claims 1-7, and is characterized in that, Specifically: The material is sent from the material tank (1) to the primary heater (3) through the material pump (2) and heated to 350 °C, and then enters the secondary heater (4) for supplementary heating to ensure that it enters the reactor (22) at 350 °C. In the reactor (22): Under the subcritical hydrothermal condition, waste oil recovery and upgrading are carried out. The upgraded oil products are separated and stored, and the uncompletely decomposed waste liquid is further treated through an oxidation process. Under the supercritical water oxidation condition, the waste liquid and the oxidant jointly enter the reactor (22) to carry out a complete oxidation reaction, converting organic pollutants into carbon dioxide and water, and finally achieving harmless discharge.

Images