A riser heat exchanger and method of use thereof

Abstract

The application discloses an ascending pipe heat exchanger and a use method thereof, which comprises an outer cylinder, a heat-conducting material body, a coil pipe and an inner cylinder; the outer cylinder is concentrically arranged outside the inner cylinder, a heat-conducting space is arranged between the outer wall of the outer cylinder and the inner wall of the inner cylinder; the coil pipe is arranged in the heat-conducting space, and the heat-conducting material body is filled in the heat-conducting space; wherein the heat-conducting material body is a homogeneous mixture of metal heat-conducting powder and phase change material; the high heat-conducting performance of the metal heat-conducting material is utilized, the gas production of the heat exchanger is effectively improved, the temperature of the raw coal gas is greatly reduced, and the phenomenon of graphite deposition is effectively prevented; meanwhile, the phase change characteristics of the phase change material are utilized, the temperature of the inner wall of the inner cylinder is ensured to be kept in a preset phase change temperature range in the whole coke oven production cycle, and the phenomenon of coke oil deposition at the end of coking is avoided; meanwhile, the phenomenon of black smoke emission when the water seal cover is opened before coke pushing can be avoided.

Description

Technical Field

[0001] This invention belongs to the technical field of waste heat recovery equipment, and specifically relates to a riser heat exchanger and its usage method. Background Technology

[0002] Currently, existing riser heat exchangers include coil heat exchangers and jacketed heat exchangers. In actual production, jacketed heat exchangers have high heat exchange efficiency, but tar is prone to form on the inner wall of the riser when the raw gas temperature is low in the later stage of coking. Black smoke is emitted from the riser when the water seal cover is opened before coking. Furthermore, when the tar buildup is thick, it can easily lead to a decrease in the heat exchange efficiency of the jacketed heat exchanger. Coil heat exchangers transfer heat through the heat-conducting material between the coil and the inner and outer cylinders. Due to the limitations of the heat-conducting material's thermal conductivity, the gas production of coil heat exchangers is relatively low. At the same time, when the amount and temperature of raw gas change significantly during the coking process, the temperature field inside the coil changes significantly within a cycle, making coil heat exchangers prone to tube rupture accidents. Summary of the Invention

[0003] In view of the technical problems existing in the prior art, the present invention provides a riser heat exchanger and its usage method to solve the technical problems of low gas production and easy tube rupture accidents in existing coil heat exchangers.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0005] This invention provides a riser heat exchanger, comprising an outer cylinder, a thermally conductive material body, a coil, and an inner cylinder; the outer cylinder is concentrically sleeved on the outside of the inner cylinder, and a thermally conductive space is provided between the outer wall of the outer cylinder and the inner wall of the inner cylinder; the coil is arranged in the thermally conductive space, and the thermally conductive material body fills the thermally conductive space; wherein, the thermally conductive material body is a homogeneous mixture of metal thermally conductive powder and phase change material.

[0006] Furthermore, the phase transition temperature of the phase change material is 500-600℃.

[0007] Furthermore, in the thermally conductive material body, the mass percentage of the metal thermally conductive powder is 30%-70%, and the remainder is a phase change material; the particle size of the metal thermally conductive powder is 10-50 mesh, and the particle size of the phase change material is 10-50 mesh.

[0008] Furthermore, the metal thermally conductive powder is one of copper powder, iron powder, cadmium powder, and lead powder; the phase change material is one of Al / Si composite material, Ca(NO3)2, Al / Si / Mg composite material, Al / Al2Cu composite material, Mg / Mg2Ca composite material, and Al / Al2Cu / Al2CuMg composite material.

[0009] Furthermore, it also includes an upper flange and a lower flange; the upper flange is fixedly disposed at the upper end of the outer cylinder and the inner cylinder, and the lower flange is fixedly disposed at the lower end of the outer cylinder and the inner cylinder.

[0010] Furthermore, the upper flange is used to connect to the tee bridge pipe, and the lower flange is used to connect to the base.

[0011] Furthermore, it also includes an insulating outer shell and an insulating layer; the insulating outer shell is disposed on the outside of the outer cylinder, and the insulating layer is disposed between the outer wall of the outer cylinder and the inner wall of the insulating outer shell.

[0012] Furthermore, the coil is made of boiler steel; wherein the pressure resistance of the coil is not less than 6.4 MPa.

[0013] Furthermore, the inner cylinder is made of alloy steel; wherein the temperature resistance of the alloy steel is not less than 1500℃.

[0014] The present invention also provides a method of using a riser heat exchanger, comprising the following steps:

[0015] The raw coal gas to be heated enters from the lower end of the inner cylinder and rises along the inner cylinder. During the rising process, the raw coal gas exchanges heat with the inner cylinder, the heat-conducting material, and the heat exchange medium in the coil, so that the temperature of the raw coal gas to be heated is reduced to a preset temperature value, and then flows out through the upper end of the inner cylinder. The heat exchange medium in the coil adopts an inflow or outflow method of bottom inflow and top outflow.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0017] This invention provides a riser heat exchanger and its usage method. A heat-conducting material body is placed in the heat-conducting space between the inner and outer cylinders, and a mixture of metal heat-conducting powder and phase change material is used as the heat-conducting material body. The high thermal conductivity of the metal heat-conducting material effectively increases the gas production of the heat exchanger, significantly reducing the temperature of the raw coal gas and thus effectively preventing graphite formation. Simultaneously, the phase change characteristics of the phase change material ensure that the inner wall temperature of the inner cylinder remains within a preset phase change temperature range throughout the entire coke oven production cycle, avoiding tar buildup at the end of coking. It also prevents black smoke from escaping when the water seal is opened before coke pushing. Furthermore, by using a mixture of metal heat-conducting powder and phase change material as the heat-conducting material body, a relatively stable temperature field is ensured for the coils throughout the coke oven production cycle, minimizing changes in the material stress range of the coils and preventing water leakage caused by stress fatigue. This significantly improves the service life and heat exchange efficiency of the heat exchanger.

[0018] Furthermore, by installing an insulation shell on the outside of the outer cylinder and an insulation layer between the insulation shell and the outer cylinder, heat loss can be reduced and the gas production of the riser pipe can be increased. At the same time, the insulation layer can reduce the surface temperature of the riser pipe and avoid the risk of burns to operators. Attached Figure Description

[0019] Figure 1 This is a cross-sectional view of the riser heat exchanger described in this invention.

[0020] The components are: 1. Upper flange, 2. Insulation shell, 3. Insulation layer, 4. Outer cylinder, 5. Thermally conductive material body, 6. Coil, 7. Inner cylinder, and 8. Lower flange. Detailed Implementation

[0021] To make the technical problems solved by the present invention, the technical solutions, and the beneficial effects clearer, the following specific embodiments provide a further detailed description of the present invention. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of the invention.

[0022] As attached Figure 1 As shown, the present invention provides a riser heat exchanger, including an upper flange 1, an insulated outer shell 2, an insulation layer 3, an outer cylinder 4, a thermally conductive material body 5, a coil 6, an inner cylinder 7, and a lower flange 8; the outer cylinder 4 is concentrically sleeved on the outside of the inner cylinder 7, the upper flange 1 is located at the upper end of the outer cylinder 4 and the inner cylinder 7, and the lower flange 8 is located at the lower end of the outer cylinder 4 and the inner cylinder 7; the insulated outer shell 2 covers the outside of the outer cylinder 4, and the insulation layer 3 is located between the outer wall of the outer cylinder 4 and the inner wall of the insulated outer shell 2.

[0023] The closed space formed by the lower end face of the upper flange 1, the inner wall of the outer cylinder 4, the outer wall of the inner cylinder 7, and the upper end face of the lower flange 8 serves as a heat conduction space; the coil 6 is arranged between the outer cylinder 4 and the inner cylinder 7 and is evenly distributed in the heat conduction space; the heat conduction material 5 fills the heat conduction space and is in close contact with the inner wall of the outer cylinder 4, the outer wall of the inner cylinder 7, and the outer wall of the coil 6.

[0024] In this invention, the upper flange 1 is used to connect to the tee bridge pipe, and the lower flange 8 is used to connect to the base; the heat insulation shell 2 is made of 304 stainless steel; the upper flange 1 is welded to the upper end of the heat insulation shell 2, the upper end of the outer cylinder 4, and the upper end of the inner cylinder 7, and the lower flange 8 is welded to the lower end of the heat insulation shell 2, the lower end of the outer cylinder 4, and the lower end of the inner cylinder 7.

[0025] In this invention, the thermally conductive material body 5 is a homogeneous mixture of metal thermally conductive powder and phase change material; the phase change temperature of the phase change material is 500-600℃; in the thermally conductive material body 5, the mass percentage of metal thermally conductive powder is 30%-70%, and the remainder is phase change material; the particle size of the metal thermally conductive powder is 10-50 mesh, and the particle size of the phase change material is 10-50 mesh; preferably, the metal thermally conductive powder is one of copper powder, iron powder, cadmium powder, and lead powder; the phase change material is one of Al / Si composite material, Ca(NO3)2, Al / Si / Mg composite material, Al / Al2Cu composite material, Mg / Mg2Ca composite material, and Al / Al2Cu / Al2CuMg composite material.

[0026] In this invention, the coil 6 is made of boiler steel; the pressure resistance of the coil 6 is not less than 6.4 MPa; a heat exchange medium is disposed inside the coil 6; the lower end of the coil 6 is led out near the lower flange 8 and connected to the feed pipeline of the heat exchange medium; the upper end of the coil 6 is led out near the upper flange 1 and connected to an external steam-water two-phase flow pipeline; the coil 6 adopts a bottom-in, top-out heat exchange medium flow mode, ensuring the residence time of the heat exchange medium in the coil 6 and effectively improving the heat exchange efficiency; the inner cylinder 7 is made of alloy steel; the temperature resistance of the alloy steel is not less than 1500℃; preferably, the alloy steel has the properties of resistance to sulfur corrosion and hydrogen corrosion.

[0027] Working principle and usage:

[0028] In the riser heat exchanger of the present invention, the raw coal gas to be heated enters from the lower end of the inner cylinder 7 and rises along the inner cylinder 7. During the rising process, the raw coal gas exchanges heat with the inner cylinder 7, the heat-conducting material body 5 and the heat exchange medium in the coil 6, so that the temperature of the raw coal gas to be heated is reduced to a preset temperature value and flows out through the upper end of the inner cylinder 7. The heat exchange medium in the coil 6 adopts a bottom-in and top-out flow method.

[0029] The riser heat exchanger and its usage method described in this invention use a mixture of metal thermally conductive powder and phase change material as the thermally conductive material. The high thermal conductivity of the metal thermally conductive powder increases the steam production rate of the heat exchanger, reduces the temperature of the raw coal gas, and prevents graphite deposition. Simultaneously, by adding phase change material, the inner wall temperature of the coil is maintained within a preset phase change temperature range throughout the entire coke oven production cycle. This effectively prevents tar buildup on the inner wall of the riser at the end of the coking process and avoids black smoke emission when the water seal is opened.

[0030] In this invention, by incorporating a phase change material within the heat-conducting material, the coil is effectively kept in a relatively stable temperature field throughout the entire coke oven production cycle. This minimizes variations in the material stress range of the coil, preventing stress fatigue and subsequent leakage. Furthermore, the riser heat exchanger described in this invention can increase the steam production rate by approximately 20-30%, preventing graphite and tar buildup during its operation. This effectively compensates for the shortcomings of existing riser heat exchangers and is of significant importance for energy conservation and emission reduction in coking plants.

[0031] The above embodiments are merely one of the implementation methods for achieving the technical solution of the present invention. The scope of protection claimed by the present invention is not limited to this embodiment, but also includes any variations, substitutions and other implementation methods that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention.

Claims

1. A riser heat exchanger, characterized in that, The device includes an outer cylinder (4), a heat-conducting material body (5), a coil (6), and an inner cylinder (7). The outer cylinder (4) is concentrically fitted outside the inner cylinder (7), and a heat-conducting space is provided between the outer wall of the outer cylinder (4) and the inner wall of the inner cylinder (7). The coil (6) is arranged in the heat-conducting space, and the heat-conducting material body (5) is filled in the heat-conducting space. The heat-conducting material body (5) is a homogeneous mixture of metal heat-conducting powder and phase change material. The phase change temperature of the phase change material is 500-600℃; In the thermally conductive material body (5), the mass percentage of the metal thermally conductive powder is 30%-70%, and the remainder is a phase change material; The particle size of the thermally conductive metal powder is 10-50 mesh, and the particle size of the phase change material is 10-50 mesh. The thermally conductive metal powder is one of copper powder, iron powder, cadmium powder, and lead powder; the phase change material is one of Al / Si composite material, Ca(NO3)2, Al / Si / Mg composite material, Al / Al2Cu composite material, Mg / Mg2Ca composite material, and Al / Al2Cu / Al2CuMg composite material.

2. The riser heat exchanger according to claim 1, characterized in that, It also includes an upper flange (1) and a lower flange (8); the upper flange (1) is fixedly disposed at the upper end of the outer cylinder (4) and the inner cylinder (7), and the lower flange (8) is fixedly disposed at the lower end of the outer cylinder (4) and the inner cylinder (7).

3. A riser heat exchanger according to claim 2, characterized in that, The upper flange (1) is used to connect to the tee bridge pipe, and the lower flange (8) is used to connect to the base.

4. A riser heat exchanger according to claim 1, characterized in that, It also includes an insulating shell (2) and an insulating layer (3); the insulating shell (2) is covered on the outside of the outer cylinder (4), and the insulating layer (3) is disposed between the outer wall of the outer cylinder (4) and the inner wall of the insulating shell (2).

5. A riser heat exchanger according to claim 1, characterized in that, The coil (6) is made of boiler steel; wherein the pressure resistance of the coil (6) is not less than 6.4 MPa.

6. A riser heat exchanger according to claim 1, characterized in that, The inner cylinder (7) is made of alloy steel; wherein the temperature resistance of the alloy steel is not less than 1500℃.

7. The method of using a riser heat exchanger as described in claim 1, characterized in that, Includes the following steps: The raw coal gas to be heated enters from the lower end of the inner cylinder (7) and rises along the inner cylinder (7); during the rising process, the raw coal gas to be heated exchanges heat with the heat exchange medium in the inner cylinder (7), the heat-conducting material body (5) and the coil (6) so that the temperature of the raw coal gas to be heated is reduced to the preset temperature value and flows out through the upper end of the inner cylinder (7); wherein, the heat exchange medium in the coil (6) adopts the inflow or outflow method of bottom inflow and top outflow.

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