Supercritical hydrothermal combustion device and method

Abstract

A supercritical hydrothermal combustion device includes a device body as a combustion chamber, a hydrothermal flame generator is arranged on the upper side of the device body, the hydrothermal flame generator is provided with a plurality of high-pressure organic slurry nozzles and a plurality of high-pressure oxidant nozzles, an igniter is arranged at the outlet of each nozzle, a supercritical thermal fluid guide pipe penetrates into the device body from the top surface of the device body, a slurry outlet is opened at the bottom of the device body, a residue separation component is arranged at the bottom of the supercritical thermal fluid guide pipe, the solid phase residue and a small part of the liquid phase product produced by the hydrothermal flame generator combustion flow out from the slurry outlet, and the remaining liquid phase product enters the supercritical thermal fluid guide pipe after being filtered by the residue separation component and flows out from the supercritical thermal fluid outlet at the top thereof, completing the rough separation process of solid phase and liquid phase products. The present invention realizes the rapid ignition, stable and clean combustion of solid phase or solid-containing fuels such as fossil fuels (such as coal) and urban / industrial sludge, and the effective separation of slag flow after combustion.

Description

Technical Field

[0001] The present invention belongs to the technical field of advanced combustion and energy-saving and environmental protection, and in particular relates to a supercritical hydrothermal combustion device and method. Background Art

[0002] Supercritical water refers to water in a special state where both the temperature and pressure are higher than its critical point (Tc = 374.15°C, Pc = 22.12MPa). Supercritical water oxidation technology uses the special properties of supercritical water such as low viscosity, low dielectric constant, and high diffusivity to make the organic matter completely dissolved in it react with the oxidant quickly and thoroughly in a homogeneous phase, and the carbon element in the organic matter is converted into carbon dioxide, chlorine, sulfur, phosphorus and other elements are converted into corresponding inorganic salts, and most of the nitrogen element is converted into nitrogen gas, so as to achieve efficient and harmless treatment of organic waste. Supercritical water oxidation is a green, efficient and thorough organic waste harmless treatment and disposal technology, and is known as the most promising organic waste treatment technology in the 21st century. Supercritical water combustion technology is a new type of internationally advanced combustion technology, which can be regarded as a violent supercritical water oxidation technology that produces a "hydrothermal flame", also known as a "water-fire compatible" combustion technology. The local high temperature of more than 1000°C in the hydrothermal flame zone can achieve rapid oxidation and degradation of organic matter in fossil fuels and pollutants, while releasing abundant heat.

[0003] At present, the problems of salt deposition and corrosion have restricted the low-cost and reliable industrial implementation of supercritical water oxidation technology to a certain extent. The high-temperature zone of 300-410℃ is the material corrosion sensitive zone and the inorganic salt rapid precipitation zone in the supercritical water oxidation process system. The equipment serving in this working condition zone faces a relatively severe risk of corrosion and blockage caused by salt deposition. If the supercritical hydrothermal flame is mixed with a lower temperature material (<300℃) to achieve the rapid heating of the latter, or the rapid supercritical hydrothermal flame ignition and combustion of the lower material is directly achieved, the high-incidence area of ​​equipment corrosion and salt deposition blockage in the 300-410℃ temperature zone can be avoided. In addition, in the field of energy, conventional coal-fired power generation systems and coal-fired industrial boilers are in principle "burning coal in one fire" in a gaseous environment with air as an oxidant, and the fly ash, sulfur oxides, nitrogen oxides and other industrial pollutants produced have caused huge environmental pollution. Supercritical hydrothermal combustion of fossil fuels such as coal is a technology with a very broad prospect. This technology is a new combustion technology that can achieve efficient and clean utilization of coal without the need for end-of-pipe control of pollutants. Compared with conventional coal combustion technology, supercritical hydrothermal combustion technology of coal can achieve the reduction of pollutants NO without the need for terminal devices such as desulfurization, denitrification and dust removal. x 、SO xThe source control of dust can easily achieve low-cost capture of CO2, and has extremely superior environmental performance. However, the hydrothermal combustion of solid fuels such as coal and sludge will still generate solid-phase burnt ember slurry. If it is not handled properly, it will block subsequent devices and affect the normal operation of the whole. Therefore, a hydrothermal combustion device that can achieve rapid ignition of fuel and effective separation of slag flow after combustion is the key to achieving efficient and clean combustion of solid or solid-containing fuels such as coal and sludge. Summary of the invention

[0004] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide a supercritical hydrothermal combustion device and method, so as to achieve rapid ignition, stable and clean combustion of solid or solid-containing fuels such as fossil fuels (such as coal) and urban / industrial sludge, and effective separation of slag flow after combustion, so as to achieve efficient and pollution-free conversion of their chemical energy into thermal energy.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] A supercritical hydrothermal combustion device comprises a device body 6 as a combustion chamber, a hydrothermal flame generator 1 is arranged on the upper side of the device body 6, the hydrothermal flame generator 1 is provided with a plurality of high-pressure organic slurry nozzles 7 and a plurality of high-pressure oxidant nozzles 8, an igniter 2 is arranged at the outlet of each nozzle, a supercritical thermal fluid guide pipe 4 penetrates into the device body 6 from the top surface of the device body 6, a slurry outlet D is opened at the bottom of the device body 6, a residue separation component 5 is arranged at the bottom of the supercritical thermal fluid guide pipe 4, the solid phase residue and a small amount of liquid phase products generated by the combustion of the hydrothermal flame generator 1 flow out from the slurry outlet D, the remaining liquid phase products enter the supercritical thermal fluid guide pipe 4 after being filtered by the residue separation component 5 and flow out from the supercritical thermal fluid outlet C at the top thereof, completing the rough separation process of solid phase and liquid phase products.

[0007] The lower part of the device body 6 is a conical structure, and its size parameters ensure that the residue separation component 5 can be immersed in the liquid phase product during the combustion process.

[0008] Each of the high-pressure organic slurry nozzles 7 is connected to a high-pressure organic slurry inlet A, and each of the high-pressure oxidant nozzles 8 is connected to a high-pressure oxidant inlet B. The pressures at the high-pressure organic slurry inlet A and the high-pressure oxidant inlet B are both not less than 23 MPa.

[0009] The igniter 2 includes but is not limited to a heating rod, and the residue separation component 5 includes but is not limited to a microporous structure.

[0010] The space enclosed by the outer side of the supercritical hot fluid guide pipe 4 and the inner wall of the device body 6 is appropriately matched with the size of the hydrothermal flame to prevent the hydrothermal flame from scouring the wall surface.

[0011] The outlet centerline of the hydrothermal flame generator 1 is tilted downward with an inclination angle of not less than 5°, so as to ensure that the burnt slag slurry rotates downward, so as to facilitate the separation of the burnt slag slurry from the supercritical thermal fluid under the action of centrifugal force and the residue separation component 5.

[0012] The flame jet exiting the hydrothermal flame generator 1 enters the device body 6 along the tangential direction and moves in the form of a downward swirl.

[0013] The outer side of the device body 6 is wrapped by a high-efficiency cooling jacket 3. The high-efficiency cooling jacket 3 is a jacket structure or a single-layer / multi-layer spiral channel structure. A coolant inlet E and a coolant outlet F are provided on the high-efficiency cooling jacket 3. The coolant is water, air, heat transfer oil, organic slurry or oxidant.

[0014] The present invention also provides a supercritical hydrothermal combustion method based on the supercritical hydrothermal combustion device, wherein the organic slurry and the oxidant are respectively sprayed into the hydrothermal flame generator 1 through the high-pressure organic slurry nozzle 7 and the high-pressure oxidant nozzle 8 at the same time, and ignite under the action of the igniter 2, forming a flame jet entering the annulus between the device body 6 and the supercritical thermal fluid guide pipe 4, and the reaction flow with the flame moves in the form of a downward vortex; the solid phase residue after the reaction, under the action of inertia, adheres to the inner wall of the device body 6 and flows out from the slurry outlet D along with part of the liquid phase products, while the vast majority of the other liquid phase products are filtered by the residue separation component 5 and enter the supercritical thermal fluid guide pipe 4, and finally flow out from the supercritical thermal fluid outlet C, completing the entire hydrothermal combustion process and the rough separation process of solid and liquid phase products.

[0015] The oxidant includes but is not limited to liquid oxygen, oxygen or air, and the organic slurry includes but is not limited to coal slurry, municipal sludge, oil sludge or petrochemical residue.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] 1. The configuration of the supercritical thermal fluid guide tube takes advantage of the fact that the center of the reactor is almost liquid due to the swirling motion of the solid-phase reactants, and the cooperation of the residue separation component realizes the function of real-time separation of liquid products (supercritical water, carbon dioxide and nitrogen and a small amount of excess oxygen) and solid product residues (containing sulfate, nitric acid / nitrite, etc.) during the full hydrothermal combustion of the solid-phase reactants. This also saves the subsequent separation steps and creates conditions for subsequent treatment.

[0018] 2. The arrangement of the hydrothermal flame generator and the upper side of the igniter not only ensures the generation of swirling downward motion when the reactants are incident, but also maximizes the use of the space between the supercritical thermal fluid guide tube, ensuring a longer flame length as much as possible, and maximizing the processing capacity under the condition of a certain device volume, fully releasing and exerting the potential of hydrothermal combustion, and controlling the source of pollutants NOx, SOx, and dust. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a front view schematic diagram of the present invention.

[0020] Figure 2 It is a top view schematic diagram of the present invention.

[0021] Wherein: 1. Hydrothermal flame generator; 2. Ignitor; 3. High-efficiency cooling jacket; 4. Supercritical thermal fluid guide pipe; 5. Residue separation component; 6. Device body; 7. High-pressure organic slurry nozzle; 8. High-pressure oxidant nozzle; A. High-pressure organic slurry inlet; B. High-pressure oxidant inlet; C. Supercritical thermal fluid outlet; D. Slag slurry outlet; E. Coolant inlet; F. Coolant outlet. DETAILED DESCRIPTION

[0022] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0023] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0024] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0025] like Figure 1 and Figure 2As shown, a supercritical hydrothermal combustion device mainly includes a hydrothermal flame generator 1, an igniter 2, a device body 6 and a supercritical thermal fluid guide tube 4. The hydrothermal flame generator 1 is arranged on the upper side of the device so that its spray direction is tangential, and the igniter 2 can select a heating rod. The supercritical thermal fluid guide tube 4 is located inside the device body 6 and is led out from the center of the top surface of the device body 6. The space enclosed by the outer side of the supercritical thermal fluid guide tube 4 and the inner wall of the device body 6 is appropriately matched with the size of the hydrothermal flame to prevent the hydrothermal flame emitted by the hydrothermal flame generator 1 from scouring the wall surface.

[0026] A residue separation assembly 5 is provided at the bottom of the supercritical thermal fluid guide pipe 4. The residue separation assembly 5 may be a microporous structure, such as a flat microporous structure. The top of the supercritical thermal fluid guide pipe 4 is a supercritical thermal fluid outlet C; the lower part of the device body 6 is conical, and a slurry outlet D is provided at the bottom; the size parameters of the device body 6 ensure that the residue separation assembly 5 can be immersed in the liquid phase product during the combustion process.

[0027] The hydrothermal flame generator 1 is provided with a plurality of high-pressure organic slurry nozzles 7 and high-pressure oxidant nozzles 8. Each high-pressure organic slurry nozzle 7 is connected to a high-pressure organic slurry inlet A, and each high-pressure oxidant nozzle 8 is connected to a high-pressure oxidant inlet B. The pressure at the high-pressure organic slurry inlet A and the high-pressure oxidant inlet B is not less than 23 MPa, or at least matched with the size parameters of the device body 6, so that most of the liquid products can be discharged from bottom to top.

[0028] The outer side of the device body 6 is wrapped by a high-efficiency cooling jacket 3. The high-efficiency cooling jacket 3 is a jacket structure or a single-layer / multi-layer spiral channel structure. The high-efficiency cooling jacket 3 is provided with a coolant inlet E and a coolant outlet F. The coolant includes but is not limited to water, air, thermal oil, organic slurry, and oxidant.

[0029] The outlet centerline of the hydrothermal flame generator 1 is tilted downward, and the tilt angle is not less than 5°, which can ensure that the burnt slag slurry rotates downward, thereby facilitating the separation of the burnt slag slurry from the supercritical thermal fluid under the action of centrifugal force and the residue separation component 5.

[0030] In the present invention, the oxidant includes but is not limited to liquid oxygen, oxygen, and air, and the organic slurry includes but is not limited to coal slurry, municipal sludge, oil sludge, and petrochemical residue.

[0031] Taking coal slurry and air as an example, the combustion method of the present invention is as follows:

[0032] The organic slurry is sprayed into the hydrothermal flame generator 1 through the high-pressure organic slurry nozzle 7 and the oxidant through the high-pressure oxidant nozzle 8 at the same time, and ignites under the action of the igniter 2, forming a flame jet that enters the annulus between the device body 6 and the supercritical thermal fluid guide pipe 4. Figure 1As shown, since the outlet center line of the hydrothermal flame generator 1 is tilted downward, the reaction flow with flames then moves in the form of a downward swirl. In this process, the solid residue after the reaction, under the action of inertia, adheres to the inner wall of the device body 6 and flows out from the slurry outlet D along with part of the liquid phase products, while the other most of the liquid phase products enter the supercritical hot fluid guide pipe 4 after being filtered by the residue separation component 5, and finally flow out from the supercritical hot fluid outlet C, completing the entire hydrothermal combustion process and the rough separation process of solid and liquid phase products. In addition, the cooling jacket is maintained in operation during the startup and operation of the entire device, and the coolant enters from the coolant inlet E and then flows out from the coolant outlet F, so as to achieve the purpose of protecting the device body 6.

[0033] In summary, the supercritical hydrothermal combustion device and method are used for the combustion of solid or solid-containing fuels such as coal and sludge, which can achieve the reduction of pollutants NO x 、SO x , and dust source control, which can easily achieve low-cost capture of CO2 and has extremely superior environmental protection performance.

Claims

1. A supercritical hydrothermal combustion device, characterized in that: The invention comprises a device body (6) serving as a combustion chamber, a hydrothermal flame generator (1) being arranged on the upper side of the device body (6), the hydrothermal flame generator (1) being provided with a plurality of high-pressure organic slurry nozzles (7) and a plurality of high-pressure oxidant nozzles (8), an igniter (2) being arranged at the outlet of each nozzle, a supercritical thermal fluid guide pipe (4) penetrating into the interior of the device body (6) from the top surface of the device body (6), a slag slurry outlet (D) being opened at the bottom of the device body (6), a residue separation assembly (5) being arranged at the bottom of the supercritical thermal fluid guide pipe (4), and a hydrothermal flame generator (1) being provided with a plurality of high-pressure organic slurry nozzles (7) and a plurality of high-pressure oxidant nozzles (8). The solid phase residue and a small amount of liquid phase products generated by the combustion of the hydrothermal flame generator (1) flow out from the slurry outlet (D), and the remaining liquid phase products are filtered by the residue separation component (5) and enter the supercritical thermal fluid guide pipe (4) and flow out from the supercritical thermal fluid outlet (C) at the top thereof, thereby completing the rough separation process of the solid phase and liquid phase products; wherein the outlet center line of the hydrothermal flame generator (1) is tilted downward, and the tilt angle is not less than 5°, so as to ensure that the burnt slurry rotates downward, so as to facilitate the separation of the burnt slurry from the supercritical thermal fluid under the action of centrifugal force and the residue separation component (5); The lower part of the device body (6) is a conical structure, and its size parameters ensure that the residue separation component (5) can be immersed in the liquid phase product during the combustion process. The residue separation component (5) is a microporous structure.

2. The supercritical water thermal combustion device according to claim 1, characterized in that: Each of the high-pressure organic slurry nozzles (7) is connected to the high-pressure organic slurry inlet (A), and each of the high-pressure oxidant nozzles (8) is connected to the high-pressure oxidant inlet (B). The pressure at the high-pressure organic slurry inlet (A) and the high-pressure oxidant inlet (B) is not less than 23 MPa.

3. The supercritical water thermal combustion device according to claim 1, characterized in that: The space enclosed by the outer side of the supercritical thermal fluid guide tube (4) and the inner wall of the device body (6) is appropriately matched to the size of the hydrothermal flame, thereby preventing the hydrothermal flame from scouring the wall surface.

4. The supercritical water thermal combustion device according to claim 1, characterized in that: The flame jet of the hydrothermal flame generator (1) enters the device body (6) along a tangential direction and moves in a downward swirling flow.

5. The supercritical water thermal combustion device according to claim 1, characterized in that: The outer side of the device body (6) is entirely wrapped by a high-efficiency cooling jacket (3), the high-efficiency cooling jacket (3) is a jacket structure, a coolant inlet (E) and a coolant outlet (F) are provided on the high-efficiency cooling jacket (3), and the coolant is water, air or heat transfer oil.

6. The supercritical water thermal combustion device according to claim 1, characterized in that: The outer side of the device body (6) is entirely wrapped by a high-efficiency cooling jacket (3), the high-efficiency cooling jacket (3) is a single-layer / multi-layer spiral channel structure, and a coolant inlet (E) and a coolant outlet (F) are provided on the high-efficiency cooling jacket (3), and the coolant is water, air or heat transfer oil.

7. The supercritical hydrothermal combustion method based on the supercritical hydrothermal combustion device according to claim 1 is characterized in that: The organic slurry and the oxidant are respectively sprayed into the hydrothermal flame generator (1) through the high-pressure organic slurry nozzle (7) and the high-pressure oxidant nozzle (8), and ignite under the action of the igniter (2), forming a flame jet that enters the annulus between the device body (6) and the supercritical thermal fluid guide pipe (4), and the reaction flow with the flame moves in the form of a downward swirl; the solid phase residue after the reaction adheres to the inner wall of the device body (6) under the action of inertia and flows out from the slurry outlet (D) along with part of the liquid phase product, while the other most of the liquid phase product is filtered by the residue separation component (5) and enters the supercritical thermal fluid guide pipe (4), and finally flows out from the supercritical thermal fluid outlet (C), completing the entire hydrothermal combustion process and the rough separation process of the solid phase and liquid phase products.

8. The supercritical hydrothermal combustion method according to claim 7, characterized in that: The oxidant is liquid oxygen, oxygen or air, and the organic slurry is coal slurry, urban sludge or oil sludge.

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