Corrosion inhibition type organic waste supercritical hydrothermal combustion treatment system

Abstract

The invention relates to the technical field of organic waste harmless treatment, in particular to a corrosion inhibition type organic waste supercritical hydrothermal combustion treatment system. In order to solve the problems of serious corrosion of a current supercritical hydrothermal combustion treatment system and resource waste after supercritical hydrothermal combustion treatment, the invention provides a corrosion inhibition type organic waste supercritical hydrothermal combustion treatment system. By injecting supercritical water and additionally arranging a hydrogen supply unit, the corrosion problem of a subcritical zone preheating section and a subcritical zone cooling section of a supercritical hydrothermal combustion treatment system is solved at low cost; and the problem of resource waste is further solved by recycling and reusing hydrogen in the corrosion inhibition type organic waste supercritical hydrothermal combustion treatment system.

Description

Technical Field

[0001] The invention relates to the technical field of harmless treatment of organic wastes, in particular to a corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system. Background Art

[0002] At present, the large-scale production of high-salt and high-concentration organic waste and the difficulty in proper treatment have seriously endangered people's lives, health and safety, and are the difficulties, pain points and key points of industrial waste treatment in my country. Supercritical water oxidation technology (SCWO) is an effective waste treatment technology. It uses the special physical and chemical properties of supercritical water to significantly change the basic properties of water density, viscosity, conductivity and dielectric constant under high temperature (usually higher than 374.3℃) and high pressure (usually higher than 22.064MPa) conditions, so that organic matter and oxygen are completely miscible, and the rapid oxidation and decomposition of organic matter is achieved. When organic waste undergoes a violent oxidation reaction with oxygen, an obvious hydrothermal flame will be generated. This technology for treating organic waste is called supercritical hydrothermal combustion (SCHC). Supercritical hydrothermal combustion technology can efficiently treat various organic toxic wastewaters and wastes, including waste gas, wastewater and solid waste discharged from factories, as well as the harmless treatment of waste chemical weapons in the military.

[0003] Although supercritical hydrothermal combustion technology has the advantages of fast reaction speed and thorough treatment, it still faces some difficult problems in practical applications. The most prominent and difficult to avoid problem is the corrosion of equipment. The high temperature and high pressure operating conditions have strict requirements on the equipment materials, and currently no metal material can completely avoid corrosion under supercritical water conditions. Especially in a supercritical water environment containing a large amount of oxidants, the corrosion rate of metals is faster than that under normal temperature conditions. The equipment not only faces high temperature and high pressure operating conditions, but also usually contains various highly corrosive ions in the treated organic waste. Therefore, the equipment corrosion problem of the supercritical hydrothermal combustion treatment system is very serious, which not only affects the treatment efficiency of organic waste, but also may affect the normal operation of the system.

[0004] In addition, in the subcritical water system, the ion product of water reaches its maximum value at about 280°C. In this temperature range, H + and OH -The concentration is very high, which accelerates the metal corrosion ion reaction. The corrosion is mainly electrochemical corrosion, which is the main reason for the aggravation of corrosion in subcritical water. Therefore, the corrosion in subcritical water is often more serious than that in supercritical water. The preheating section of the supercritical hydrothermal combustion treatment system and the cooling section behind the reactor have subcritical temperature zones. Therefore, the preheater and cooler in the supercritical hydrothermal combustion treatment system often face the most serious corrosion problems.

[0005] In the currently known supercritical hydrothermal combustion technology, supercritical hydrothermal combustion treatment equipment is generally manufactured only by using more expensive metal materials, and the corrosion problem of the equipment is difficult to control. Currently, the corrosion problem has become an important factor restricting the development of supercritical hydrothermal combustion technology, and the harmless products after supercritical hydrothermal combustion treatment are also difficult to be utilized as resources. The above problems affect the further development of supercritical hydrothermal combustion technology. Summary of the invention

[0006] In order to solve the serious corrosion problem of the current supercritical hydrothermal combustion treatment system and the resource waste problem after supercritical hydrothermal combustion treatment, the present invention provides a corrosion-inhibiting supercritical hydrothermal combustion treatment system for organic waste. On the basis of meeting the requirements of supercritical hydrothermal combustion treatment of organic waste, the corrosion problem of the subcritical zone preheating section and the subcritical zone cooling section of the supercritical hydrothermal combustion treatment system is solved at a low cost by injecting supercritical water and adding a hydrogen supply unit. The subcritical zone preheating section is composed of a secondary preheater, an ejector and a first pipeline between the secondary preheater and the ejector, and the outer pipeline of the preheater is the subcritical zone cooling section; and the resource waste problem is solved by recycling and reusing the hydrogen in the corrosion-inhibiting supercritical hydrothermal combustion treatment system for organic waste.

[0007] To achieve the above object, the technical solution of the present invention is as follows:

[0008] A corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system, comprising:

[0009] A reactor is provided for supercritical hydrothermal combustion treatment of organic waste.

[0010] An organic waste pool is used to supply organic waste to a reactor, a first pipeline is connected between the two, a primary preheater, a secondary preheater and an ejector are arranged in sequence on the first pipeline, the reactor material outlet end is also connected with the ejector through a second pipeline, the ejector is used to eject the supercritical thermal fluid at the reactor material outlet end, the organic waste is preheated by the primary preheater and the secondary preheater to obtain preheated organic waste, and after the preheated organic waste is mixed with the supercritical thermal fluid, the subcritical temperature section can be skipped, thereby avoiding the problem of severe corrosion in the subcritical zone.

[0011] The oxidant supply unit is used to provide oxygen required for supercritical hydrothermal combustion treatment. While supplying oxygen to the reactor, the oxidant supply unit also passes oxygen into the first pipeline between the primary preheater and the secondary preheater.

[0012] The hydrogen supply unit provides hydrogen to reduce the redox potential of the subcritical cooling section of the supercritical hydrothermal combustion treatment system. The hydrogen supply unit is connected to the material outlet of the reactor.

[0013] A membrane separator is used as a hydrogen recovery bypass. The hydrogen supply unit and the hydrogen recovery bypass together constitute a hydrogen injection unit, which is used to recover hydrogen in a supercritical hydrothermal combustion system for treating organic waste. The membrane separator is arranged on a third pipeline, one end of the third pipeline is connected to the material outlet of the reactor, and the other end is connected to the outlet of the hydrogen supply unit. A product separator is also arranged on the third pipeline between the reactor and the membrane separator, and a gas phase product outlet and a non-gas phase product outlet are provided on the product separator.

[0014] The third pipeline is connected with the fourth pipeline, the second switch valve is installed on the fourth pipeline, the outer pipelines of the first-stage preheater and the second-stage preheater are the subcritical cooling section, and the outer pipelines of the first-stage preheater and the second-stage preheater are the subcritical cooling section.

[0015] The present invention comprises a primary preheater, a secondary preheater, a reactor and a product separator to form an organic waste oxidation unit. The outlet of the secondary preheater is connected to the reactor by an ejector, and the gas phase product outlet of the product separator is connected to the inlet of a membrane separator. The present invention performs supercritical hydrothermal combustion treatment on various organic wastes through the organic waste oxidation unit to achieve harmless treatment of organic wastes, so that non-gas phase products generated by subsequent treatment can be harmlessly discharged or reused. At the same time, the heat of the primary preheater and the secondary preheater comes from the supercritical hot fluid at the material outlet end of the reactor, and the waste heat is recovered and reused through the primary preheater and the secondary preheater, which has high economic benefits. The oxidant supply unit and the hydrogen supply unit not only ensure the safe operation of the system, but also solve the serious corrosion problem of the subcritical zone of the inner and outer pipelines of the primary preheater and the secondary preheater.

[0016] Preferably, the hydrogen supply unit includes a liquid hydrogen tank and a liquid hydrogen vaporizer, a fifth pipeline is connected between the liquid hydrogen tank and the material outlet end of the reactor, the liquid hydrogen vaporizer is arranged on the fifth pipeline, and a liquid hydrogen pump is also arranged on the fifth pipeline between the liquid hydrogen tank and the liquid hydrogen vaporizer.

[0017] The outlet end of the membrane separator on the third pipeline is connected to the fifth pipeline. A pressure pump is also arranged on the third pipeline between the membrane separator and the fifth pipeline. The membrane separator realizes the recovery of hydrogen on the one hand, and discharges gaseous products other than hydrogen on the other hand. The present invention utilizes the special physical and chemical properties of supercritical water to continuously and harmlessly treat organic waste, solves the pain points and difficulties of the current treatment of organic waste, and discharges the treated products harmlessly and recycles them as resources.

[0018] Preferably, a feedwater heater is also provided on the third pipeline between the reactor and the product separator, and the feedwater heater is used to heat water outside the system. The present invention uses a primary preheater, a secondary preheater and a feedwater heater as a waste heat recovery unit. The supercritical thermal fluid at the reactor outlet not only serves as a heat source for the subcritical zone preheating section of the corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system, but can also use external feedwater to deeply utilize the waste heat.

[0019] Preferably, a second oxidation-reduction potential meter is provided at the inlet end of the feedwater heater, and the second oxidation-reduction potential meter is interlocked with the liquid hydrogen pump. The second oxidation-reduction potential meter of the present invention monitors the potential of the mixture of the cooling fluid and the supercritical thermal fluid before separation in the product separator, and solves the problem of excessive oxidant in the supercritical thermal fluid at the outlet of the reactor by adjusting the opening of the liquid hydrogen pump, and solves the problem of severe oxidation corrosion of the preheater outer pipeline. By controlling the hydrogen supply amount of the hydrogen supply unit, the oxidation-reduction potential of the cooling fluid at the outlet end of the first-stage preheater outer pipeline is controlled not to exceed -0.2V, ensuring that the potential of the metal material of the preheater outer pipeline is within its passivation range.

[0020] Preferably, the oxidant supply unit includes a liquid oxygen tank and a liquid oxygen vaporizer, a sixth pipeline is connected between the liquid oxygen tank and the reactor, the liquid oxygen vaporizer is arranged on the sixth pipeline, and a liquid oxygen pump is also arranged on the sixth pipeline between the liquid oxygen tank and the liquid oxygen vaporizer.

[0021] Preferably, a seventh pipeline is provided between the sixth pipeline and the first pipeline, the seventh pipeline is located between the primary preheater and the secondary preheater, a first switch valve is provided on the seventh pipeline, a first oxidation-reduction potential meter is provided on the outlet end of the secondary preheater, the first oxidation-reduction potential meter is interlocked with the first switch valve, and the oxidant supply unit supplies oxygen to the middle section of the preheater by a liquid oxygen pump, a liquid oxygen vaporizer and the first switch valve. The present invention partially oxidizes the organic waste in the first pipeline by supplying oxygen to the middle section of the preheater, and the heat generated by oxidation promotes the preheating process of the second preheater, and also solves the problem of excessive reducing substances contained in the organic waste in the second preheater, effectively preventing the risk of hydrogen embrittlement cracking in the second preheater. The outlet oxidation-reduction potential of the secondary preheater is controlled to be not less than -0.7V by adjusting the opening of the first switch valve, thereby avoiding the risk of stress corrosion cracking caused by hydrogen embrittlement in the secondary preheater.

[0022] Preferably, a third switch valve is provided on the second pipeline, and a first thermometer is provided at the inlet end of the reactor, between the ejector and the reactor. The first thermometer is interlocked with the third switch valve. The first thermometer of the present invention can regulate the amount of supercritical water at the ejector outlet to ensure that the preheated organic waste at the second preheater outlet can skip the subcritical corrosion risk zone after mixing with the supercritical thermal fluid.

[0023] Preferably, a second switch valve is provided on the third pipeline between the secondary preheater and the primary preheater, a second thermometer is provided at the inlet end of the ejector between the secondary preheater and the ejector, and the second thermometer is interlocked with the second switch valve. The second thermometer of the present invention monitors the temperature at the outlet of the secondary preheater, and prevents the organic waste from overheating in the primary preheater and the secondary preheater by adjusting the opening of the second switch valve. The second thermometer controls the outlet temperature of the secondary preheater to not exceed 270°C.

[0024] Preferably, temperature sensors and pressure sensors are provided inside the preheater, reactor and product separator to ensure safe operation of the system.

[0025] Preferably, the product separator is connected to a pressure reducer, and the product entering the product separator still has a certain pressure. In order to solve the problem of too high harmless discharge pressure of the product separator, a pressure reducer is also connected to the product separator. The gaseous product separated by the product separator enters the membrane separator for hydrogen recovery and reuse, and the outlet of the pressure reducer discharges the harmless product to the outside, and the non-gas phase product is discharged to the outside under the action of the pressure reducer.

[0026] The present invention also protects a treatment method based on the above-mentioned corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system, comprising the following steps:

[0027] The organic waste in the organic waste pool is preheated in turn by the primary preheater and the secondary preheater to obtain preheated organic waste. The preheated organic waste is mixed with the supercritical hot fluid discharged from the material outlet of the reactor in the ejector and transported to the reactor.

[0028] The oxygen in the liquid oxygen tank is discharged in sequence through the liquid oxygen pump and the liquid oxygen vaporizer, one way of which is transported to the reactor, and the other way is transported to the first pipeline through the seventh pipeline.

[0029] The hydrogen in the liquid hydrogen tank is discharged through the liquid hydrogen pump and the liquid hydrogen vaporizer in turn, and then mixed with the supercritical thermal fluid. The supercritical thermal fluid coming out of the reactor generally has excess oxidant, so the corrosion in the cooling section of the subcritical zone is more serious. The main function of adding hydrogen is to consume the excess oxidant and reduce the redox potential of the cooling section of the subcritical zone to achieve the effect of corrosion inhibition.

[0030] The supercritical hot fluid at the reactor material outlet is transported to the ejector via the second pipeline in one way; it is transported to the secondary preheater and the primary preheater in turn via the third pipeline to obtain a cooling fluid; it is transported via the fourth pipeline in another way, and the cooling fluid and the supercritical hot fluid at the reactor material outlet are mixed in the third pipeline, and are sent together to the feed water heater to exchange heat with the external water to obtain a heat exchange fluid.

[0031] The heat exchange fluid is transported to the product separator, and the product separator discharges the gas phase product into the membrane separator for hydrogen recovery and reuse, and the non-gas phase product is discharged through the pressure reducer.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] 1. The corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system of the present invention comprises a reactor, an organic waste pool, an oxidant supply unit, a hydrogen supply unit and a membrane separator; the oxidant supply unit provides the oxygen required for the supercritical hydrothermal combustion treatment, the hydrogen supply unit reduces the redox potential of the subcritical cooling section of the supercritical hydrothermal combustion treatment system, and the membrane separator realizes the recovery of hydrogen in the supercritical hydrothermal combustion treatment system for organic waste; the primary preheater, the secondary preheater, the reactor and the product separator constitute an organic waste oxidation unit, and various organic wastes are harmlessly treated by the organic waste oxidation unit.

[0034] The present invention is provided with a secondary preheater and an ejector. After preheating organic waste and mixing with supercritical thermal fluid, the subcritical temperature section can be skipped, thereby avoiding the problem of severe corrosion in the subcritical preheating section. The present invention also adds a hydrogen supply unit to provide hydrogen for reducing the redox potential of the subcritical cooling section, thereby solving the problem of severe corrosion in the subcritical cooling section. The present invention also recovers the waste heat of the supercritical thermal fluid at the material outlet of the reactor in the corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system through a primary preheater and a secondary preheater, thereby improving the operating efficiency of the entire system.

[0035] 2. The present invention solves the problem of hydrogen embrittlement of metal equipment caused by excessively high reducing atmosphere in the pipeline of the secondary preheater by introducing oxygen into the first pipeline between the primary preheater and the secondary preheater, promotes partial oxidation of organic waste in advance, and is also beneficial to the preheating of the secondary preheater. The ejector can eject the supercritical thermal fluid at the outlet of the reactor, and the preheated organic waste can skip the subcritical temperature section after mixing with the supercritical thermal fluid, thereby avoiding the problem of severe corrosion in the subcritical preheating section.

[0036] 3. The present invention provides hydrogen to the corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system through a hydrogen supply unit, consumes the surplus oxidant at the reactor outlet, reduces the redox potential of the subcritical cooling section, and recycles the remaining hydrogen of the product through a membrane separator, thereby utilizing the product as a resource and alleviating the serious oxidative corrosion problem of the subcritical cooling section at the reactor outlet.

[0037] 4. The corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system of the present invention solves the serious corrosion problem of the subcritical preheating section and corrosion section of the primary and secondary preheaters by optimizing the process flow while ensuring the safe operation of the supercritical hydrothermal combustion treatment system, and sets the primary and secondary preheaters and feedwater heaters for waste heat recovery. While cooling and depressurizing the supercritical hot fluid, the primary and secondary preheaters are also provided with the heat required for preheating. Finally, the hydrogen in the cooling fluid is recovered to achieve resource reuse. The present invention not only solves the corrosion problem of the equipment, but also saves the operating cost of the entire corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 A system layout diagram of a corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system provided in an embodiment of the present invention.

[0039] Description of reference numerals:

[0040] 1. Liquid hydrogen tank; 2. Liquid hydrogen vaporizer; 3. Liquid oxygen tank; 4. Liquid oxygen vaporizer; 5. Organic waste pool; 6. Primary preheater; 7. Secondary preheater; 8. Ejector; 9. Reactor; 10. Feedwater heater; 11. Product separator; 12. Membrane separator; 13. Depressurizer; 14. Liquid hydrogen pump; 15. Liquid oxygen pump; 16. Material pump; 17. Booster pump; 18. First pipeline; 19. Second pipeline; 20. Third pipeline; 21. Fourth pipeline; 22. Fifth pipeline; 23. Sixth pipeline; 24. Seventh pipeline; V1, first switch valve; V2, second switch valve; V3, third switch valve; T1, first thermometer; T2, second thermometer; ORP1, first oxidation-reduction potential measuring instrument; ORP2, second oxidation-reduction potential measuring instrument. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0042] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making any creative work shall fall within the scope of protection of the present invention.

[0043] At present, although supercritical hydrothermal combustion technology has the advantages of fast reaction speed and thorough treatment, the supercritical hydrothermal combustion treatment system not only faces high temperature and high pressure operating conditions, but also contains various highly corrosive ions in the treated organic waste. Therefore, the corrosion problem of the supercritical hydrothermal combustion treatment system is very serious, which not only affects the treatment efficiency of organic waste, but also may affect the normal operation of the system. In addition, the corrosion in subcritical water is often more serious than that in supercritical water, and there is a subcritical temperature zone in the subcritical preheating section and subcritical cooling section of the supercritical hydrothermal combustion treatment system. Therefore, the preheater and cooler in the supercritical hydrothermal combustion treatment system often face the most serious corrosion problem. Based on this, the corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system of the present invention introduces hydrogen. The addition of hydrogen consumes the surplus oxidant and reduces the redox potential of the subcritical cooling section to achieve the corrosion inhibition effect. The present invention is also provided with a secondary preheater and an ejector. After the preheated organic waste is mixed with the supercritical thermal fluid, the subcritical temperature section can be skipped to achieve the purpose of corrosion inhibition in the subcritical preheating section, thereby achieving a low-cost solution to the corrosion problem of the supercritical hydrothermal combustion treatment system. At the same time, the hydrogen in the corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system can also be recycled to avoid the problem of waste of resources.

[0044] The technical solution of the present invention is further described below by means of specific examples. In the following examples, the methods described are conventional methods unless otherwise specified; the reagents and materials described are commercially available unless otherwise specified.

[0045] Example 1

[0046] A corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system, such as Figure 1 As shown, including:

[0047] The reactor 9 is used for supercritical hydrothermal combustion treatment of organic wastes. The reactor 9 is provided with a first inlet end and a second inlet end.

[0048] An organic waste pool 5 is used to supply organic waste to a reactor 9, and a first pipeline 18 is connected between the two. A primary preheater 6, a secondary preheater 7 and an ejector 8 are sequentially arranged on the first pipeline 18. A material pump 16 is also arranged on the first pipeline 18 between the organic waste pool 5 and the primary preheater 6. The primary preheater 6 is provided with a first outlet end and a second outlet end, the secondary preheater 7 is provided with a first outlet end, a second outlet end, a first inlet end and a second inlet end, and the ejector 8 is provided with a first inlet end and a second inlet end. The first pipeline 18 is connected to the first outlet end of the primary preheater 6, the first inlet end and the first outlet end of the secondary preheater 7, and the first inlet end of the ejector 8. The material outlet end of the reactor 9 and the second inlet end of the ejector 8 are also connected through a second pipeline 19.

[0049] The oxidant supply unit is used to provide oxygen for supercritical hydrothermal combustion treatment. While supplying oxygen to the reactor 9, the oxidant supply unit also passes into the first pipeline 18 between the primary preheater 6 and the secondary preheater 7; when supplying oxygen to the reactor 9, it is connected to the second inlet end of the reactor 9, and when supplying oxygen to the first pipeline 18, it is connected to the first inlet end of the secondary preheater 7.

[0050] The hydrogen supply unit is used to provide hydrogen to overcome the corrosion problem of the corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system. The hydrogen supply unit is connected to the material outlet end of the reactor 9.

[0051] The membrane separator 12 is used to recover hydrogen in the corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system. The membrane separator 12 is provided with a first outlet end and a second outlet end. The membrane separator 12 is arranged on the third pipeline 20. The two ends of the third pipeline 20 are respectively connected to the material outlet end of the reactor 9 and the hydrogen supply unit. A product separator 11 is also arranged on the third pipeline 20 between the material outlet end of the reactor 9 and the membrane separator 12. The product separator 11 is provided with a gas phase product outlet and a non-gas phase product outlet.

[0052] The fourth pipeline 21 is connected through the third pipeline 20, and the external pipelines of the primary preheater 6 and the secondary preheater 7 are installed on the third pipeline 20. The supercritical hot fluid enters the secondary preheater 7 through the second inlet end of the secondary preheater 7, and enters the primary preheater 6 through the second inlet end of the primary preheater 6. After heat exchange with the primary preheater 6 and the secondary preheater 7, the supercritical hot fluid is transported to the feed water heater.

[0053] Furthermore, the hydrogen supply unit includes a liquid hydrogen tank 1 and a liquid hydrogen vaporizer 2. A fifth pipeline 22 is connected between the liquid hydrogen tank 1 and the material outlet end of the reactor 9. The liquid hydrogen vaporizer 2 is arranged on the fifth pipeline 22, and a liquid hydrogen pump 14 is also arranged on the fifth pipeline 22 between the liquid hydrogen tank 1 and the liquid hydrogen vaporizer 2.

[0054] On the third pipeline 20 , the first outlet end of the membrane separator 12 is connected to the fifth pipeline 22 , and the first outlet end of the membrane separator 12 is connected to the inlet of the booster pump 17 , and the booster pump 17 is arranged between the first outlet end of the membrane separator 12 and the fifth pipeline 22 .

[0055] Furthermore, a feed water heater 10 is also provided on the third pipeline 20 between the reactor 9 and the product separator 11 .

[0056] Furthermore, a second oxidation-reduction potential measuring instrument ORP2 is provided at the inlet end of the feedwater heater 10, and the second oxidation-reduction potential measuring instrument ORP2 is interlocked with the liquid hydrogen pump 14. By controlling the hydrogen supply amount of the hydrogen supply unit, the oxidation-reduction potential of the cooling fluid at the outlet end of the primary preheater 6 is controlled not to exceed -0.2V, ensuring that the potential of the metal material of the preheater outer pipeline is within its passivation range.

[0057] Furthermore, the oxidant supply unit includes a liquid oxygen tank 3 and a liquid oxygen vaporizer 4. A sixth pipeline 23 is connected between the liquid oxygen tank 3 and the reactor 9. The liquid oxygen vaporizer 4 is arranged on the sixth pipeline 23. A liquid oxygen pump 15 is also arranged on the sixth pipeline 23 between the liquid oxygen tank 3 and the liquid oxygen vaporizer 4.

[0058] Furthermore, a seventh pipeline 24 is provided between the sixth pipeline 23 and the first pipeline 18, and the seventh pipeline 24 is located between the primary preheater 6 and the secondary preheater 7. A first switch valve V1 is provided on the seventh pipeline 24, and a first oxidation-reduction potential meter ORP1 is provided on the outlet end of the secondary preheater 7, and the first oxidation-reduction potential meter ORP1 is interlocked with the first switch valve V1. The outlet oxidation-reduction potential of the secondary preheater 7 is controlled to be not less than -0.7V by adjusting the opening of the first switch valve V1, so as to avoid the risk of stress corrosion cracking caused by hydrogen embrittlement in the secondary preheater 7.

[0059] Furthermore, a third switch valve V3 is provided on the second pipeline 19 , a first thermometer T1 is provided on the first inlet end of the reactor 9 , and the first thermometer T1 is interlocked with the third switch valve V3 .

[0060] Furthermore, a second switch valve V2 is provided on the fourth pipeline 21 between the secondary preheater 7 and the primary preheater 6, and a second thermometer T2 is provided on the first inlet end of the ejector 8, and the second thermometer T2 is interlocked with the second switch valve V2. The second thermometer T2 controls the outlet temperature of the secondary preheater 7 not to exceed 270°C.

[0061] Furthermore, temperature sensors and pressure sensors are provided inside the primary preheater 6 , the secondary preheater 7 , the reactor 9 and the product separator 11 .

[0062] Furthermore, the second outlet end of the product separator 11 is connected to the pressure reducer 13 .

[0063] Application method:

[0064] The invention discloses a corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system for treating organic waste, which comprises the following steps:

[0065] The organic waste in the organic waste pool 5 is preheated in turn by the primary preheater 6 and the secondary preheater 7 to obtain preheated organic waste. The preheated organic waste is mixed with the supercritical hot fluid discharged from the material outlet of the reactor 9 in the ejector 8 and transported to the reactor 9.

[0066] The oxygen in the liquid oxygen tank 3 is discharged in turn through the liquid oxygen pump 15 and the liquid oxygen vaporizer 4, and then transported to the reactor 9 in one way and to the first pipeline 18 through the seventh pipeline 24 in the other way. The organic waste is partially oxidized in the first pipeline 18, and the heat generated by the oxidation promotes the preheating process of the second preheater 7, and also solves the problem of excessive reducing substances contained in the organic waste in the second preheater 7, thereby effectively preventing the risk of hydrogen embrittlement cracking in the second preheater 7.

[0067] The hydrogen in the liquid hydrogen tank 1 is discharged through the liquid hydrogen pump 14 and the liquid hydrogen vaporizer 2 in turn, and then mixed with the supercritical thermal fluid. The addition of hydrogen solves the problem of excess supercritical thermal fluid oxidant at the reactor material outlet end, and reduces the redox potential of the subcritical cooling section.

[0068] The supercritical hot fluid at the reactor material outlet is transported to the ejector 8 via the second pipeline 19 in one way; it is transported to the outer pipeline of the preheater via the third pipeline 20 in another way, and exchanges heat with the secondary preheater 7 and the primary preheater 6 in turn to obtain a cooling fluid; it is transported via the fourth pipeline 21 in another way, and the cooling fluid and the supercritical hot fluid at the reactor material outlet are mixed in the third pipeline 20, and are sent together to the feed water heater 10 to exchange heat with the external water to obtain a heat exchange fluid.

[0069] The heat exchange fluid is transported to the product separator 11 , and the product separator 11 discharges the gaseous product into the membrane separator 11 for hydrogen recovery and reuse, and the non-gas phase product is discharged. The recovered hydrogen enters the fifth pipeline 22 and mixes with the hydrogen in the fifth pipeline 22 .

[0070] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these changes and variations. The above-described embodiments are only preferred embodiments for fully illustrating the present invention, and their protection scope is not limited thereto. Equivalent substitutions or changes made by those skilled in the art on the basis of the present invention are all within the protection scope of the present invention, and the protection scope of the present invention shall be subject to the claims.

Claims

1. A corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system, characterized in that: include: A reactor (9) for treating organic waste with supercritical hydrothermal combustion; An organic waste pool (5) is used to supply organic waste to the reactor (9), and the two are connected by a first pipeline (18). The first pipeline (18) is provided with a primary preheater (6), a secondary preheater (7) and an ejector (8) in sequence. The material outlet of the reactor (9) is also connected to the ejector (8) by a second pipeline (19). The ejector (8) is used to eject supercritical hot fluid at the material outlet of the reactor (9); An oxidant supply unit, which is used to provide oxygen required for supercritical hydrothermal combustion treatment, wherein the oxidant supply unit supplies oxygen to the reactor (9) and also passes oxygen into the first pipeline (18) between the first preheater (6) and the second preheater (7); A hydrogen supply unit connected to the material outlet of the reactor (9); A membrane separator (12) for recovering hydrogen in a system for treating organic waste by supercritical hydrothermal combustion, wherein the membrane separator (12) is arranged on a third pipeline (20), and both ends of the third pipeline (20) are respectively connected to a material outlet of the reactor (9) and a hydrogen supply unit, and a product separator (11) is also arranged on the third pipeline (20) between the reactor (9) and the membrane separator (12); The third pipeline (20) is connected to a fourth pipeline (21), the outer pipelines of the first-stage preheater (6) and the second-stage preheater (7) are both installed on the third pipeline (20), the hydrogen supply unit is used to provide hydrogen to reduce the redox potential of the subcritical cooling section of the supercritical hydrothermal combustion treatment system, and the outer pipelines of the first-stage preheater (6) and the second-stage preheater (6) are the subcritical cooling section.

2. The corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system according to claim 1 is characterized in that: The hydrogen supply unit comprises a liquid hydrogen tank (1) and a liquid hydrogen vaporizer (2); a fifth pipeline (22) is connected between the liquid hydrogen tank (1) and a material outlet end of the reactor (9); the liquid hydrogen vaporizer (2) is arranged on the fifth pipeline (22); and a liquid hydrogen pump (14) is also arranged on the fifth pipeline (22) between the liquid hydrogen tank (1) and the liquid hydrogen vaporizer (2); The outlet end of the membrane separator (12) on the third pipeline (20) is connected to the fifth pipeline (22).

3. A corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system according to claim 2, characterized in that: A feed water heater (10) is also provided on the third pipeline (20) between the reactor (9) and the product separator (11).

4. The corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system according to claim 3 is characterized in that: A second oxidation-reduction potential measuring instrument (ORP2) is provided at the inlet end of the feed water heater (10), and the second oxidation-reduction potential measuring instrument (ORP2) is interlocked with the liquid hydrogen pump (14).

5. The corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system according to claim 1 is characterized in that: The oxidant supply unit comprises a liquid oxygen tank (3) and a liquid oxygen vaporizer (4); a sixth pipeline (23) is connected between the liquid oxygen tank (3) and the reactor (9); the liquid oxygen vaporizer (4) is arranged on the sixth pipeline (23); and a liquid oxygen pump (15) is also arranged on the sixth pipeline (23) between the liquid oxygen tank (3) and the liquid oxygen vaporizer (4).

6. The corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system according to claim 5 is characterized in that: A seventh pipeline (24) is provided between the sixth pipeline (23) and the first pipeline (18); the seventh pipeline (24) is located between the primary preheater (6) and the secondary preheater (7); a first switch valve (V1) is provided on the seventh pipeline (24); a first oxidation-reduction potential meter (ORP1) is provided at the outlet end of the secondary preheater (7); the first oxidation-reduction potential meter (ORP1) is interlocked with the first switch valve (V1).

7. The corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system according to claim 1 is characterized in that: A third switch valve (V3) is provided on the second pipeline (19), and a first thermometer (T1) is provided at the inlet end of the reactor (9) and between the ejector (8) and the reactor (9), and the first thermometer (T1) is interlocked with the third switch valve (V3).

8. The corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system according to claim 1 is characterized in that: A second switch valve (V2) is provided on the fourth pipeline (21), and a second thermometer (T2) is provided at the inlet end of the ejector (8) and between the secondary preheater (7) and the ejector (8), and the second thermometer (T2) is interlocked with the second switch valve (V2).

9. The corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system according to claim 1, characterized in that: The primary preheater (6), the secondary preheater (7), the reactor (9) and the product separator (11) are all provided with temperature sensors and pressure sensors.

10. The corrosion-inhibiting organic waste supercritical hydrothermal combustion treatment system according to claim 1, characterized in that: The product separator (11) is also connected to a pressure reducer (13).

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