A supercritical hydrothermal combustion device suitable for water-coal slurry

Abstract

The present application belongs to the technical field of efficient and clean utilization of water-coal slurry, and specifically relates to a supercritical hydrothermal combustion device suitable for water-coal slurry, including: a supercritical hydrothermal burner, having a first combustion chamber, a top opening, and a bottom vent pipe; a supercritical water oxidation reactor, fixed at the bottom of the supercritical hydrothermal burner, having a second combustion chamber, a top and a bottom discharge pipe; a feed nozzle, spraying the mixed material into the first combustion chamber in the form of mist particles to form a supercritical hydrothermal combustion flame, and the reaction products will then enter the second combustion chamber for supercritical water oxidation reaction, and the final reaction products will be discharged from the discharge pipe. In the supercritical hydrothermal combustion device of the present application, the supercritical hydrothermal combustion flame in the first combustion chamber has a higher temperature, which can make the coal in the particle state undergo oxidation reaction more fully, thereby improving the utilization rate of the coal; in addition, the products in the first combustion chamber can be further oxidized and decomposed by the second combustion chamber to improve the material processing efficiency.

Description

Technical Field

[0001] The present application belongs to the technical field of efficient and clean utilization of water-coal slurry, and specifically relates to a supercritical hydrothermal combustion device suitable for water-coal slurry. Background Art

[0002] Coal resources are an important part of my country's energy and play a vital role in my country's industrial production. As more and more coal resources are used in daily production, the combustion of coal furnaces causes an increase in the emission of dust, sulfide and nitrogen oxides, causing serious pollution to the atmosphere.

[0003] To this end, actively exploring and developing an advanced coal-fired system that is efficient, clean, free of sulfides, nitrogen oxides and low in carbon emissions is of great significance for the efficient use of energy and the sustainable development of the environment. Summary of the invention

[0004] In order to solve at least one technical problem existing in the prior art, the present application provides a supercritical hydrothermal combustion device suitable for water-coal slurry.

[0005] The present application discloses a supercritical hydrothermal combustion device suitable for water-coal slurry, comprising:

[0006] A supercritical water thermal burner, which has a first combustion chamber inside, a bottom of which has an opening communicating with the first combustion chamber, and a top of which is penetrated by a vent pipe communicating with the first combustion chamber;

[0007] A supercritical water oxidation reactor, which has a second combustion chamber inside, has an opening to the second combustion chamber at the top, and has a discharge pipe in communication with the second combustion chamber at the bottom, wherein the supercritical water oxidation reactor is coaxially arranged at the bottom of the supercritical water thermal burner and is sealed and fixedly connected to the supercritical water thermal burner in a manner that the openings are opposite to each other;

[0008] A feed inlet, which is opened through a predetermined position on the overall structure consisting of the supercritical water thermal burner and the supercritical water oxidation reactor;

[0009] A feed nozzle, used to fully mix the preheated water-coal slurry and the predetermined oxidant transported therein, and then spray the mixed materials into the first combustion chamber in the form of mist particles from the feed port;

[0010] Among them, the mixed material in the form of mist particles can form a supercritical hydrothermal combustion flame in the first combustion chamber to generate a primary reaction product. A part of the mixed hot fluid in the primary reaction product can be discharged from the vent pipe, and the rest of the primary reaction product enters the second combustion chamber through the bottom opening to undergo a supercritical water oxidation reaction to generate a final reaction product containing supercritical water, supercritical carbon dioxide and solid slag, which is discharged from the discharge pipe.

[0011] According to at least one embodiment of the present application, the feed port is arranged on the side wall of the supercritical water oxidation reactor near its top opening;

[0012] Correspondingly, the feed nozzle includes:

[0013] A mixing tube, the inlet end of which is located outside the supercritical water oxidation reactor, and the outlet end of which extends vertically from the feed port to the center of the supercritical water oxidation reaction chamber, and then extends axially upward to a position close to the top opening of the supercritical water oxidation reactor;

[0014] A nozzle, one end of which is connected to the outlet end of the mixing tube, and the other end of which extends axially upward into the first combustion chamber and does not exceed the axial midpoint of the first combustion chamber;

[0015] a water-coal slurry feed pipe, the outlet end of which is connected to the inlet end of the mixing pipe;

[0016] The fuel inlet pipe has an outlet end which penetrates the side wall of the water-coal slurry feed pipe and is communicated with the inner cavity of the water-coal slurry feed pipe.

[0017] According to at least one embodiment of the present application, the supercritical water oxidation reactor further comprises:

[0018] A shielding cylinder is vertically arranged in the second combustion chamber, and the axial ends of the shielding cylinder respectively have openings, the top opening of which is sealed and connected to the top opening of the supercritical water oxidation reactor, and the bottom opening of which extends to a position close to the discharge pipe, wherein

[0019] After the outlet end of the mixing tube extends from the feed port, it first penetrates the shielding tube and then continues to extend.

[0020] According to at least one embodiment of the present application, the supercritical water thermal combustion cylinder includes:

[0021] The bottom plate has an opening extending through the middle thereof;

[0022] The first combustion tube has an opening at its axial bottom end and a first through hole passing through its axial top end, and the ventilation pipe is arranged at the first through hole. In addition, the first combustion tube is fixedly arranged on the upper surface of the base plate through its bottom end, and the opening at the bottom end of the first combustion tube corresponds to the position of the opening on the base plate.

[0023] According to at least one embodiment of the present application, the supercritical water oxidation reactor comprises:

[0024] A top plate, wherein an opening is provided through the middle thereof, and the top plate and the bottom plate are sealed and fixedly connected in a manner that the upper and lower surfaces are opposite and the positions of the openings are corresponding;

[0025] The second combustion tube has an opening at its axial top end and a second through hole passing through its axial bottom end, and the discharge pipe is arranged at the second through hole. In addition, the second combustion tube is fixedly arranged on the lower surface of the top plate through its top end, and the opening at the top end of the second combustion tube corresponds to the position of the opening on the top plate.

[0026] According to at least one embodiment of the present application, the supercritical water thermal combustion cylinder further includes:

[0027] A first temperature control device is used to control the temperature of the first combustion tube wall from the outside; and / or

[0028] The supercritical water oxidation reactor also includes:

[0029] The second temperature control device is used to control the temperature of the wall of the second combustion tube from the outside.

[0030] According to at least one embodiment of the present application, the first temperature control device includes:

[0031] An upper pressure-bearing sleeve, which is similar in shape to the first combustion tube, comprises an opening at the bottom end and a third through hole at the top end, and is coaxially sleeved on the outside of the first combustion tube and fixedly connected to the upper surface of the bottom plate, so as to form a first annular cavity between the inner wall of the upper pressure-bearing sleeve and the outer wall of the first combustion tube;

[0032] A first liquid inlet pipe, one end of which is used as a liquid inlet, and the other end is fixedly arranged on the outer wall of the upper pressure-bearing sleeve at a position close to the bottom plate and communicated with the first annular cavity;

[0033] The first liquid outlet pipe is in the shape of a right-angle bend pipe, which includes a first straight pipe and a second straight pipe connected end to end. The open end of the first straight pipe is fixedly connected to the third through hole of the upper pressure-bearing sleeve from the outside. In addition, the inner diameter of the first straight pipe is larger than the outer diameter of the ventilation pipe. One end of the ventilation pipe extends into the first straight pipe from the outside and extends along the axial direction of the first straight pipe to the first through hole of the first combustion tube for connection.

[0034] According to at least one embodiment of the present application, the second temperature control device includes:

[0035] A lower pressure-bearing sleeve, which is similar in shape to the second combustion tube, comprises an opening at the top and a fourth through hole at the bottom, and is coaxially sleeved on the outside of the second combustion tube and fixedly connected to the lower surface of the top plate, so as to form a second annular cavity between the inner wall of the lower pressure-bearing sleeve and the outer wall of the second combustion tube;

[0036] A second liquid inlet pipe, one end of which is used as a liquid inlet, and the other end is fixedly arranged on the outer wall of the lower pressure sleeve near the top plate and communicated with the second annular cavity;

[0037] The second liquid outlet pipe is in the shape of a right-angle bend pipe, which includes a third straight pipe and a fourth straight pipe connected end to end. The open end of the third straight pipe is fixedly connected to the fourth through hole of the lower pressure sleeve from the outside. In addition, the inner diameter of the third straight pipe is larger than the outer diameter of the discharge pipe. One end of the discharge pipe extends into the third straight pipe from the outside and extends along the axial direction of the third straight pipe to the second through hole of the second combustion tube for connection.

[0038] According to at least one embodiment of the present application, a spiral flow channel is formed in the first annular cavity and / or the second annular cavity.

[0039] According to at least one embodiment of the present application, the temperatures of the preheated water-coal slurry and the predetermined oxidant delivered to the feed nozzle are both 430-500° C.; and

[0040] The predetermined oxidant is oxygen or air or oxygen-enriched air; and

[0041] The reaction pressure in the first combustion chamber is 23-30 MPa, and the reaction temperature is 800-1000° C.; and

[0042] The reaction pressure in the second combustion chamber is 23-30 MPa, and the reaction temperature is 400-600°C.

[0043] This application has at least the following beneficial technical effects:

[0044] 1) In the supercritical hydrothermal combustion device for water-coal slurry of the present application, a feed nozzle is used to transport the mixed materials in the form of mist particles (or fine mist) to the first combustion chamber of the supercritical hydrothermal burner, and a supercritical hydrothermal combustion flame is formed in the first combustion chamber. The hydrothermal combustion flame has a higher temperature, which can make the coal in the particle state undergo an oxidation reaction more fully, thereby improving the utilization rate of the coal; and, since a supercritical water oxidation reactor is provided at the bottom of the supercritical hydrothermal burner, the incompletely decomposed and oxidized materials transported from the first combustion chamber can be further oxidized and decomposed through the second combustion chamber, thereby improving the material processing efficiency;

[0045] 2) In the supercritical hydrothermal combustion device for water-coal slurry of the present application, the feed nozzle adopts a high-pressure nozzle form, and a mixing tube is provided as a jet mixing zone, so that the nozzle material and the fuel are mixed more evenly, and the speed and concentration of the mixed material can be effectively regulated by setting the nozzle at the outlet; further, the feed nozzle adopts the combustion mode of the intermediate feed upper nozzle, so that the products of supercritical hydrothermal combustion: supercritical water, supercritical carbon dioxide and solid particles are easier to separate, and the materials after supercritical hydrothermal combustion are compared with conventional combustion methods, and no sulfide, nitride and dust are generated;

[0046] 3) In the supercritical hydrothermal combustion device for water-coal slurry of the present application, a shielding plate is provided in the supercritical hydrothermal burner, which is conducive to the sedimentation of residues at the bottom and effectively reduces the recovery rate of unsettled particles;

[0047] 4) In the supercritical hydrothermal combustion device for water-coal slurry of the present application, by setting the first temperature control device, the reaction temperature can be controlled more quickly and efficiently during the supercritical hydrothermal combustion reaction, and the first combustion chamber can be heated more evenly, avoiding the problem of local slagging in the process of treating water-coal slurry due to large temperature gradient, and at the same time, the use temperature of the material of the first combustion tube (or boiler) can be reduced, and steam can be generated for reuse; in addition, the spiral flow channel design can further improve the temperature regulation efficiency and avoid the local flow channel dead zone;

[0048] 5) In the supercritical hydrothermal combustion device for water-coal slurry of the present application, by setting the second temperature control device, the reaction temperature can be controlled more quickly and efficiently during the supercritical water oxidation reaction, and the use temperature of the second combustion tube (or boiler) material can be reduced, and steam can be generated for reuse; in addition, the spiral flow channel design can further improve the temperature regulation efficiency and avoid the local flow channel dead zone;

[0049] 6) In the supercritical hydrothermal combustion device for water-coal slurry of the present application, the upper pressure sleeve and the lower pressure sleeve can also be selected as ordinary steel, while the corresponding first combustion tube and the second combustion tube are made of special steel, thereby reducing the use of special steel in the entire device and saving costs;

[0050] 7) The structure of the supercritical hydrothermal combustion device suitable for water-coal slurry of the present application makes it easier to reuse the mixed hot fluid (supercritical water and carbon dioxide) in the final product of the reaction. For example, it can enter a turbine for power generation, and the carbon dioxide can be easily recovered after the exhaust steam is separated by gas and liquid, thereby achieving zero carbon dioxide emissions; in addition, the separated water can be returned to the water-coal slurry preparation system to achieve zero water emissions. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 This is a structural cross-sectional view of a supercritical hydrothermal combustion device applicable to water-coal slurry in the present application;

[0052] Figure 2 This is a schematic diagram of the structure of a feed nozzle in a supercritical hydrothermal combustion device for water-coal slurry;

[0053] in:

[0054] 1-supercritical water thermal burner; 11-first combustion chamber; 12-ventilation pipe; 13-bottom plate; 14-first combustion tube;

[0055] 2-supercritical water oxidation reactor; 21-second combustion chamber; 22-discharge pipe; 23-shielding cylinder; 24-top plate; 25-second combustion cylinder;

[0056] 3-feeding port;

[0057] 4-feed nozzle; 41-mixing tube; 42-spray pipe; 43-water-coal slurry feed pipe; 44-fuel feed pipe;

[0058] 51-upper pressure sleeve; 52-first annular cavity; 53-first liquid inlet pipe; 54-first liquid outlet pipe; 541-first straight pipe; 542-second straight pipe;

[0059] 61 - lower pressure sleeve; 62 - second annular cavity; 63 - second liquid inlet pipe; 64 - second liquid outlet pipe; 641 - third straight pipe; 642 - fourth straight pipe. DETAILED DESCRIPTION

[0060] In order to make the purpose, technical scheme and advantages of the implementation of the present application clearer, the technical scheme in the embodiment of the present application will be described in more detail below in conjunction with the drawings in the embodiment of the present application. In the drawings, the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The described embodiments are part of the embodiments of the present application, not all of the embodiments. The embodiments described below with reference to the drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limitations on the present application.

[0061] It should be understood that the technical terms that may be involved in the description of this application, such as "vertical", "horizontal", "up and down", "left and right", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the scope of protection of this application.

[0062] Before describing the coal clean utilization thermal system and its operation method in detail, the concepts of supercritical water and supercritical water thermal combustion are described as follows:

[0063] Supercritical water (SCW) refers to water when the temperature and pressure reach a certain value (Tc ≥ 374.3℃, Pc ≥ 22.1MPa), and the density of water expanded by high temperature and the density of water vapor compressed by high pressure are exactly the same. At this time, there is no difference between liquid and gas of water, and they are completely blended together to become a new fluid with high pressure and high temperature. Under supercritical conditions, the properties of water have changed greatly, and its density, dielectric constant, viscosity, diffusion coefficient, conductivity and solubility are different from those of ordinary water.

[0064] Supercritical hydrothermal combustion (SCHC) refers to a new type of combustion method in which a fuel or a certain concentration of organic matter and an oxidant undergo a violent oxidation reaction in supercritical water (temperature>374℃, pressure>22MPa) to produce a water-heat flame. By utilizing the characteristics of supercritical water, an exothermic reaction with water and carbon dioxide as the main products occurs under homogeneous conditions between organic matter and supercritical water. Its advantages are that the supercritical hydrothermal combustion reactor can avoid carbon deposition, solid fuel reaction is sufficient, reaction time is short and has higher thermal efficiency. Therefore, as a new type of coal efficient and clean utilization technology, supercritical hydrothermal combustion can avoid gas pollution such as sulfide, nitrogen oxides and dust produced by conventional combustion.

[0065] The following is combined with Figure 1 The aero-engine sealing structure of the present application is further described in detail.

[0066] The present application discloses a supercritical hydrothermal combustion device suitable for water-coal slurry, comprising a supercritical hydrothermal burner 1, a supercritical water oxidation reactor 2, a feed inlet 3 and a feed nozzle 4.

[0067] Specifically, the supercritical water thermal burner 1 has a first combustion chamber 11 inside, the bottom of the supercritical water thermal burner 1 has an opening connected to the first combustion chamber 11, and a ventilation pipe 12 connected to the first combustion chamber 11 is penetrated through the top of the supercritical water thermal burner 1.

[0068] The supercritical water oxidation reactor 2 has a second combustion chamber 21 inside, the top of the supercritical water oxidation reactor 2 has an opening to the second combustion chamber 21, and a discharge pipe 22 connected to the second combustion chamber 21 is arranged through the bottom of the supercritical water oxidation reactor 2; wherein, the supercritical water oxidation reactor 2 is coaxially arranged at the bottom of the supercritical water thermal burner 1, and is sealed and fixedly connected to the supercritical water thermal burner 1 in a manner that the openings (i.e., the bottom opening of the supercritical water thermal burner 1 and the top opening of the supercritical water oxidation reactor 2) are opposite to each other.

[0069] The feed port 3 is opened through a predetermined position on the overall structure consisting of the supercritical water thermal burner 1 and the supercritical water oxidation reactor 2 .

[0070] The interior of the feed nozzle 4 can receive the preheated water-coal slurry and the predetermined oxidant delivered from the outside and mix them fully. Furthermore, the mixed materials can be sprayed into the first combustion chamber 11 in the form of mist particles from the feed port 3 for reaction. Among them, the mixed materials in the form of mist particles can increase the contact area with the predetermined oxidant, so that the reaction temperature is high and the reaction is sufficient.

[0071] Specifically, the mixed material in the form of mist particles sprayed into the first combustion chamber 11 can form a supercritical water thermal combustion flame in the first combustion chamber 11 to generate primary reaction products (supercritical water, supercritical carbon dioxide, and sulfate converted from sulfur and nitrate solids converted from nitrogen); further, a part of the mixed hot fluid (supercritical water+supercritical carbon dioxide) in the primary reaction products can be discharged from the vent pipe 12, and the remaining primary reaction products enter the second combustion chamber 21 through the bottom opening to undergo a supercritical water oxidation reaction, so that the materials that are not completely decomposed and oxidized in the first combustion chamber can be further oxidized and decomposed into final reaction products containing supercritical water, supercritical carbon dioxide and solid slag, and discharged from the discharge pipe 22, thereby improving the material processing efficiency.

[0072] It is understandable that the feed port 3 can be arranged at a plurality of suitable positions, such as the top and side of the supercritical hydrothermal burner 1, and the feed nozzle 4 can be a plurality of matching shapes and structures.

[0073] In this embodiment, the feed port 3 is arranged on the side wall of the supercritical water oxidation reactor 2 near the top opening thereof. Figure 2 As shown, the feed nozzle 4 includes a mixing tube 41 , a nozzle 42 , a water-coal slurry feed pipe 43 , and a fuel feed pipe 44 .

[0074] Specifically, the inlet end of the mixing tube 41 is located outside the supercritical water oxidation reactor 2, and the outlet end thereof extends vertically from the feed port 3 to the center of the supercritical water oxidation reaction chamber 21, and then extends axially upward to a position close to the top opening of the supercritical water oxidation reactor 2. The purpose of the long tubular mixing tube 41 is to allow the preheated water-coal slurry and the predetermined oxidant transported from the outside to be mixed more fully.

[0075] The water-coal slurry feed pipe 43 is connected to the inlet end of the mixing tube 41 through its outlet end, so as to facilitate the delivery of the preheated water-coal slurry from the outside to the mixing tube 41; the outlet end of the fuel inlet pipe 44 passes through the side wall of the water-coal slurry feed pipe 43 and is connected to the inner cavity of the water-coal slurry feed pipe 43, so as to facilitate the delivery of the preheated predetermined oxidant from the outside to the mixing tube 41.

[0076] In addition, one end of the nozzle 42 ( Figure 1 The bottom end) is connected to the outlet end ( Figure 1 The nozzle 42 has a top (middle and upper end), and the other end of the nozzle 42 extends axially upward to the first combustion chamber 11, and does not exceed the axial midpoint of the first combustion chamber 11, so that the mixed material is sprayed into the first combustion chamber 11 in the form of mist particles, and the speed and concentration of the mixed material can be effectively regulated; further, the structural design of the mixing tube 41 and the nozzle 42 makes the entire feed nozzle adopt the combustion method of the intermediate feed upper nozzle, so that the products of supercritical hydrothermal combustion: supercritical water, supercritical carbon dioxide and solid particles are easier to separate, and the materials after supercritical hydrothermal combustion are compared with conventional combustion methods, and no sulfide, nitride and dust are generated.

[0077] Furthermore, in the supercritical water oxidation reaction cylinder 2 of the present application, a shielding cylinder 23 may be provided to allow the residue to settle at the bottom and effectively reduce the recovery rate of unsettled particles.

[0078] Specifically, the shielding tube 23 is arranged in the second combustion chamber 21 along the vertical direction, and has openings at both axial ends; the shielding tube 23 is sealed and connected to the top opening of the supercritical water oxidation reactor 2 through its top opening, and its bottom opening extends to a position close to the discharge pipe 22; correspondingly, at this time, after the outlet end of the mixing tube 41 extends from the feed port 3, it first penetrates the shielding tube 23 and then continues to extend to the corresponding position.

[0079] Furthermore, the supercritical water thermal burner 1 and supercritical water oxidation reactor 2 of the present application can be configured into various shapes and structures as needed.

[0080] In this embodiment, the supercritical water thermal burner 1 may preferably include a base plate 13 and a first combustion tube 14 .

[0081] Specifically, an opening is provided in the middle of the bottom plate 13; and the axial bottom end of the first combustion tube 14 has an opening, and the axial top end thereof is provided with a first through hole, at which time, the above-mentioned ventilation pipe 12 is connected to the first through hole; in addition, the first combustion tube 14 is sealed and fixed at its bottom end (i.e., the bottom opening end) on the upper surface of the bottom plate 13 by welding, bolts, etc., and the opening at the bottom end of the first combustion tube 14 corresponds to the position of the opening on the bottom plate 13 (the shapes and sizes of the two can be determined according to needs, such as circular or polygonal).

[0082] In this embodiment, the structure of the supercritical water oxidation reactor 2 is preferably similar to that of the supercritical water thermal burner 1 , and may include a top plate 24 and a second combustion tube 25 .

[0083] Specifically, an opening is provided through the middle of the top plate 24 , and the top plate 24 and the bottom plate 13 are sealed and fixed (welded, bolted, etc.) with the upper and lower surfaces facing each other and the opening positions corresponding to each other.

[0084] Furthermore, the axial top end of the second combustion tube 25 has an opening, and the axial bottom end is penetrated by a second through hole, and the above-mentioned discharge pipe 22 is connected to the second through hole; in addition, the top end (i.e., the top opening end) of the second combustion tube 25 is sealed and fixed on the lower surface of the top plate 24 by welding, bolts, etc., and the opening at the top end of the second combustion tube 25 corresponds to the position of the opening on the top plate 24 (similarly, the shapes and sizes of the two can be determined according to needs).

[0085] Furthermore, when the supercritical hydrothermal combustion reaction is performed, the reaction pressure in the first combustion chamber 11 is usually 23-30 MPa, and the reaction temperature is 800-1000° C. In order to be able to control the reaction temperature more quickly and efficiently when the supercritical hydrothermal combustion reaction is performed, the supercritical hydrothermal burner 1 of the present application may also include a first temperature control device for regulating the temperature of the wall of the first combustion tube 14 from the outside.

[0086] It is also understandable that the first temperature control device can adopt a variety of suitable device structures as needed, such as cooling by a water cooling jacket, cooling by an air cooling jacket, and cooling by jacketing other temperature control materials on the surface; in this embodiment, the first temperature control device can include an upper pressure-bearing jacket 51 and a first liquid inlet pipe 53 and a first liquid outlet pipe 54 arranged on the upper pressure-bearing jacket 51.

[0087] Specifically, the upper pressure sleeve 51 is similar in shape to the first combustion tube 14, including an opening at the bottom end and a third through hole at the top end, and the dimensions of each part of the upper pressure sleeve 51 are slightly larger than the first combustion tube 14. Therefore, when the upper pressure sleeve 51 is coaxially sleeved on the outside of the first combustion tube 14 and fixedly connected (by welding or bolts, etc.) to the upper surface of the base plate 13, a sealed first annular cavity 52 can be formed between the inner wall of the upper pressure sleeve 51 and the outer wall of the first combustion tube 14.

[0088] One end port of the first liquid inlet pipe 53 ( Figure 1 The left end of the upper pressure sleeve 51 is used as a liquid inlet, and the other end is fixedly arranged on the outer wall of the upper pressure sleeve 51 near the bottom plate 13 and connected to the first annular cavity 52, so that the cooling liquid (such as water) can enter the first annular cavity 52 from the first liquid inlet pipe 53.

[0089] The first liquid outlet pipe 54 is in the shape of a right-angled bend pipe, and includes a first straight pipe 541 and a second straight pipe 542 connected end to end; the opening end of the first straight pipe 541 ( Figure 1 The middle and bottom end) is fixedly sealed and connected to the third through hole of the upper pressure sleeve 51 from the outside. In addition, the inner diameter of the first straight tube 541 is larger than the outer diameter of the vent pipe 12. At this time, the corresponding one end of the vent pipe 12 ( Figure 1 The first straight tube 541 is connected to the first combustion tube 14 by a first annular cavity 52. ​​The first straight tube 541 is connected to the first combustion tube 14 by a first annular cavity 52. ​​The first straight tube 541 is connected to the first combustion tube 14 by a first annular cavity 52. ​​The first combustion tube 14 ... Figure 1 The waste flows out from the center left end of the pipeline for easy recycling after treatment.

[0090] It should be further explained that the above-mentioned structure of the first temperature control device can also make the first combustion chamber 11 heated more evenly, avoiding the problem of local slagging during the treatment of water-coal slurry due to large temperature gradient, and at the same time can reduce the operating temperature of the material of the first combustion tube 14 (or boiler), and can generate steam for recycling.

[0091] In addition, in order to further improve the temperature regulation efficiency of the above-mentioned first temperature control device and avoid the occurrence of local dead zones in the flow channel, it is also preferred to design a spiral flow channel in the first annular cavity 52. ​​For example, a spiral guide vane can be provided in the first annular cavity 52 to achieve a spiral flow channel design, wherein the guide vane can be independently provided and fixed on the inner wall of the upper pressure sleeve 51 and / or the outer wall of the first combustion tube 14, or the corresponding guide vane can be directly formed when processing the inner wall of the upper pressure sleeve 51 and / or the outer wall of the first combustion tube 14.

[0092] Similarly, when conducting a supercritical water oxidation reaction, the reaction pressure in the second combustion chamber 21 is 23 to 30 MPa, and the reaction temperature is 400 to 600°C. In order to facilitate rapid and efficient control of the temperature of the wall of the second combustion tube 25 from the outside, the supercritical water oxidation reactor 2 may also include a second temperature control device similar to the first temperature control device, and further preferably, the second temperature control device includes a lower pressure sleeve 61, a second liquid inlet pipe 63 and a second liquid outlet pipe 64 arranged on the lower pressure sleeve 61.

[0093] Specifically, the lower pressure sleeve 61 is similar in shape to the second combustion tube 25, including an opening at the top and a fourth through hole at the bottom, and the dimensions of each part of the lower pressure sleeve 61 are slightly larger than the second combustion tube 25. Therefore, when the lower pressure sleeve 61 is coaxially sleeved on the outside of the second combustion tube 25 and fixedly connected (welded or bolted, etc.) to the lower surface of the top plate 24, a sealed second annular cavity 62 can be formed between the inner wall of the lower pressure sleeve 61 and the outer wall of the second combustion tube 25. It should be noted that when the lower pressure sleeve 61 is included, the supercritical water oxidation reactor 2 is equivalent to a double-layer structure. Therefore, the mixing tube 41 arranged on the outside of the supercritical water oxidation reactor 2 is equivalent to being formed by sequentially penetrating the side wall of the lower pressure sleeve 61 and the side wall of the second combustion tube 25 from the outside to the inside.

[0094] One end of the second liquid inlet pipe 63 serves as a liquid inlet, and the other end is fixedly arranged on the outer wall of the lower pressure sleeve 61 near the top plate 24 and connected to the second annular cavity 62, so that the coolant (such as water) can enter the first annular cavity 52 from the first liquid inlet pipe 53.

[0095] The second liquid outlet pipe 64 is in the shape of a right-angled bend pipe, and includes a third straight pipe 641 and a fourth straight pipe 642 connected end to end. The opening end of the third straight pipe 641 ( Figure 1 The top of the middle part) is fixedly connected to the fourth through hole of the lower pressure sleeve 61 from the outside. In addition, the inner diameter of the third straight pipe 641 is larger than the outer diameter of the discharge pipe 22. At this time, the corresponding end of the discharge pipe 22 ( Figure 1 The cooling liquid in the second annular cavity 62 is cooled and cooled, and the cooling liquid in the second annular cavity 62 is cooled. The cooling liquid in the second annular cavity 62 is cooled and cooled, and the cooling liquid in the second annular cavity 62 is cooled and cooled. Finally, the .... Finally, the cooling liquid in the second annular cavity 62 is cooled and cooled. Finally, the cooling liquid in the second annular cavity 62 is cooled and cooled. Finally, the cooling liquid in the third straight tube 641 is cooled and cooled. Finally, the cooling liquid in the second straight tube 641 is cooled and cooled. Finally, the cooling liquid in the second straight tube 641 is cooled and cooled. Finally, the cooling liquid in the second straight tube Figure 1 The wastewater flows out from the middle left end of the pipeline for recycling after treatment (such as thermal energy utilization).

[0096] Furthermore, in the supercritical hydrothermal combustion device suitable for water-coal slurry of the present application, based on the design of the above-mentioned temperature control device structure, in addition to the first combustion tube 14 and the second combustion tube 25 using special steel with fire-resistant, high-temperature resistant, high-pressure resistant and corrosion-resistant properties, the upper pressure sleeve 51 and the lower pressure sleeve 61 can be selected as ordinary steel, such as Q345R alloy steel, thereby reducing the use of special steel in the entire device and saving costs.

[0097] Furthermore, the supercritical hydrothermal combustion device suitable for water-coal slurry of the present application, through the above-mentioned structural designs, makes the mixed hot fluid (supercritical water and carbon dioxide) in the final product of the reaction easier to reuse. For example, it can enter a turbine for power generation, and the exhaust steam can be easily recovered after gas-liquid separation, thereby achieving zero carbon dioxide emissions; in addition, the separated water can be returned to the water-coal slurry pulping system to achieve zero water emissions.

[0098] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A supercritical hydrothermal combustion device suitable for water-coal slurry, It is characterized in that include: A supercritical water thermal burner (1) having a first combustion chamber (11) therein, a bottom portion thereof having an opening communicating with the first combustion chamber (11), and a top portion thereof having a vent pipe (12) communicating with the first combustion chamber (11); A supercritical water oxidation reactor (2) having a second combustion chamber (21) therein, a top of which has an opening to the second combustion chamber (21), and a bottom through which a discharge pipe (22) in communication with the second combustion chamber (21) is provided, wherein the supercritical water oxidation reactor (2) is coaxially arranged at the bottom of the supercritical water thermal burner (1), and is sealed and fixedly connected to the supercritical water thermal burner (1) in a manner that the openings face each other; A feed inlet (3) is provided through a predetermined position on the overall structure consisting of the supercritical water thermal burner (1) and the supercritical water oxidation reactor (2); A feed nozzle (4) is used to fully mix the preheated water-coal slurry and a predetermined oxidant transported therein, and then spray the mixed materials in the form of mist particles into the first combustion chamber (11) from the feed port (3); The mixed material in the form of mist particles can form a supercritical water thermal combustion flame in the first combustion chamber (11) to generate a primary reaction product. A portion of the mixed hot fluid in the primary reaction product can be discharged from the vent pipe (12), and the rest of the primary reaction product enters the second combustion chamber (21) through the bottom opening to undergo a supercritical water oxidation reaction to generate a final reaction product containing supercritical water, supercritical carbon dioxide and solid slag, which is then discharged from the discharge pipe (22).

2. The supercritical water thermal combustion device according to claim 1, It is characterized in that The feed port (3) is arranged on the side wall of the supercritical water oxidation reactor (2) at a position close to the top opening thereof; Correspondingly, the feed nozzle (4) comprises: A mixing tube (41), the inlet end of which is located outside the supercritical water oxidation reactor (2), and the outlet end of which extends vertically from the feed port (3) to the center of the supercritical water oxidation reaction chamber (21), and then extends axially upward to a position close to the top opening of the supercritical water oxidation reactor (2); A nozzle (42), one end of which is connected to the outlet end of the mixing tube (41), and the other end of which extends axially upward to the first combustion chamber (11) and does not exceed the axial midpoint of the first combustion chamber (11); A water-coal slurry feed pipe (43), the outlet end of which is connected to the inlet end of the mixing pipe (41); The fuel inlet pipe (44) has an outlet end that penetrates the side wall of the water-coal slurry feed pipe (43) and is in communication with the inner cavity of the water-coal slurry feed pipe (43).

3. The supercritical water thermal combustion device according to claim 2, It is characterized in that The supercritical water oxidation reaction tube (2) also includes: A shielding cylinder (23) is vertically arranged in the second combustion chamber (21), and the shielding cylinder (23) has openings at both axial ends, the top opening of which is sealed and connected to the top opening of the supercritical water oxidation reactor (2), and the bottom opening of which extends to a position close to the discharge pipe (22), wherein After the outlet end of the mixing tube (41) extends from the feed port (3), it first passes through the shielding tube (23) and then continues to extend.

4. The supercritical water thermal combustion device according to claim 1, It is characterized in that The supercritical water thermal combustion cylinder (1) comprises: The bottom plate (13) has an opening extending through the middle thereof; The first combustion tube (14) has an opening at its axial bottom end and a first through hole passing through its axial top end, and the ventilation pipe (12) is arranged at the first through hole. In addition, the first combustion tube (14) is fixedly arranged on the upper surface of the bottom plate (13) through its bottom end, and the opening at the bottom end of the first combustion tube (14) corresponds to the position of the opening on the bottom plate (13).

5. The supercritical water thermal combustion device according to claim 4, It is characterized in that The supercritical water oxidation reactor (2) comprises: A top plate (24) is provided with an opening at the middle thereof, and the top plate (24) and the bottom plate (13) are sealed and fixedly connected in a manner that the upper and lower surfaces are opposite and the positions of the openings are corresponding; The second combustion tube (25) has an opening at its axial top end and a second through hole passing through its axial bottom end, and the discharge pipe (22) is arranged at the second through hole. In addition, the second combustion tube (25) is fixedly arranged on the lower surface of the top plate (24) through its top end, and the opening at the top end of the second combustion tube (25) corresponds to the position of the opening on the top plate (24).

6. The supercritical water thermal combustion device according to claim 5, It is characterized in that The supercritical water thermal combustion cylinder (1) further comprises: A first temperature control device is used to control the temperature of the wall of the first combustion tube (14) from the outside; and / or The supercritical water oxidation reactor (2) also includes: The second temperature control device is used to control the temperature of the wall of the second combustion tube (25) from the outside.

7. The supercritical water thermal combustion device according to claim 6, It is characterized in that The first temperature control device comprises: an upper pressure-bearing sleeve (51), the upper pressure-bearing sleeve (51) having a similar shape to the first combustion tube (14), comprising an opening at a bottom end and a third through hole at a top end, the upper pressure-bearing sleeve (51) being coaxially sleeved on the outside of the first combustion tube (14) and fixedly connected to the upper surface of the bottom plate (13), thereby forming a first annular cavity (52) between the inner wall of the upper pressure-bearing sleeve (51) and the outer wall of the first combustion tube (14); A first liquid inlet pipe (53), one end of which serves as a liquid inlet, and the other end of which is fixedly arranged on the outer wall of the upper pressure-bearing sleeve (51) at a position close to the bottom plate (13) and communicates with the first annular cavity (52); The first liquid outlet pipe (54) is in the shape of a right-angled bend pipe, comprising a first straight pipe (541) and a second straight pipe (542) connected end to end, wherein the open end of the first straight pipe (541) is fixedly connected to the third through hole of the upper pressure-bearing sleeve (51) from the outside, and the inner diameter of the first straight pipe (541) is larger than the outer diameter of the ventilation pipe (12), and one end of the ventilation pipe (12) penetrates from the outside into the first straight pipe (541) and extends along the axial direction of the first straight pipe (541) to the first through hole of the first combustion tube (14) for connection.

8. The supercritical water thermal combustion device according to claim 7, It is characterized in that The second temperature control device comprises: a lower pressure-bearing sleeve (61), the lower pressure-bearing sleeve (61) having a similar shape to the second combustion tube (25), comprising an opening at the top end and a fourth through hole at the bottom end, the lower pressure-bearing sleeve (61) being coaxially sleeved on the outside of the second combustion tube (25) and fixedly connected to the lower surface of the top plate (24), thereby forming a second annular cavity (62) between the inner wall of the lower pressure-bearing sleeve (61) and the outer wall of the second combustion tube (25); A second liquid inlet pipe (63), one end of which serves as a liquid inlet, and the other end of which is fixedly arranged on the outer wall of the lower pressure-bearing sleeve (61) at a position close to the top plate (24) and communicates with the second annular cavity (62); The second liquid outlet pipe (64) is in the shape of a right-angle bend pipe, and comprises a third straight pipe (641) and a fourth straight pipe (642) connected end to end. The open end of the third straight pipe (641) is fixedly connected to the fourth through hole of the lower pressure sleeve (61) from the outside. In addition, the inner diameter of the third straight pipe (641) is larger than the outer diameter of the discharge pipe (22). One end of the discharge pipe (22) penetrates from the outside into the third straight pipe (641) and extends along the axial direction of the third straight pipe (641) to the second through hole of the second combustion tube (25) for connection.

9. The supercritical water thermal combustion device according to claim 8, It is characterized in that A spiral flow channel is formed in the first annular cavity (52) and / or the second annular cavity (62).

10. The supercritical water thermal combustion device according to any one of claims 1 to 9, It is characterized in that The temperatures of the preheated water-coal slurry and the predetermined oxidant delivered to the feed nozzle (4) are both 430-500° C.; and The predetermined oxidant is oxygen or air or oxygen-enriched air; and The reaction pressure in the first combustion chamber (11) is 23-30 MPa, and the reaction temperature is 800-1000° C.; and The reaction pressure in the second combustion chamber (21) is 23-30 MPa, and the reaction temperature is 400-600°C.

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