A device and method for generating hot carrier gas with oxygen-enriched combustion external to a low-temperature coal retorting furnace
By designing an oxygen-rich combustion hot carrier gas generator in the peripherals of the coal low-temperature distillation furnace, using cyclone combustion and uniformly distributed excess gas mixture layer, the over-temperature of the hot carrier gas channel of the internal combustion internal heat furnace under oxygen-rich combustion is solved. The problem of coal ash blockage achieves uniformity of air flow and heat distribution in the furnace and stability of product quality.
Patent Information
- Application Number
- CN202111679294.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2021-12-31
- Publication Date
- 2025-01-03
- Estimated Expiration
- 2041-12-31
AI Technical Summary
When the existing internal combustion internal heat coal low-temperature distillation furnace is directly subjected to oxygen-rich combustion, it causes overtemperature of the hot carrier gas channel in the furnace, slag and blockage of coal ash, resulting in uneven distribution of air flow and heat and unstable product quality.
A coal low-temperature distillation furnace with an oxygen-rich combustion hot carrier gas generator is designed, including a burner, an excess gas replenishment gun, a gas-tipped brick ring and a high-energy igniter. By evenly distributing oxygen-rich air and gas, a rotor is formed. The flow is burned and a uniformly distributed excess gas mixture layer is formed in the gas distribution loop to regulate the hot carrier gas temperature, avoid high-temperature flame erosion, and ensure uniform distribution of air flow and heat.
It effectively avoids overtemperature, coal ash slag and blockage in the furnace, ensures uniform distribution of air flow and heat in the furnace, and improves product quality stability.
Smart Images
Figure CN114321886B_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the field of low-temperature dry distillation of coal chemical industry, and in particular relates to an oxygen-enriched combustion type hot carrier gas generating device and method external to a low-temperature dry distillation furnace for coal. Background Art
[0002] Oxygen-enriched combustion internal heating coal low-temperature distillation technology is a new type of low-temperature distillation technology that can effectively improve the quality of low-temperature distillation coal gas based on the current coal low-temperature distillation technology. Oxygen-enriched combustion-supporting gas is used instead of air combustion-supporting gas to burn with coal gas to produce the hot carrier gas required for low-temperature distillation of coal. After the hot carrier gas fully exchanges heat with the coal material, it is mixed with the gas produced by the low-temperature distillation of coal to form low-temperature distillation coal gas. The use of oxygen-enriched combustion can minimize the nitrogen content introduced into the hot carrier gas due to air combustion-supporting gas, thereby reducing the nitrogen content in the low-temperature distillation coal gas, improving the quality of coal gas, expanding the application field of low-temperature distillation coal gas, and promoting the development of the downstream industrial chain.
[0003] However, the existing low-temperature coal retorting furnace is an internal combustion and internal heating structure, that is, the process of coal gas combustion to generate hot carrier gas and the process of hot carrier gas contacting and exchanging heat with coal are all carried out in the furnace. Directly replacing the combustion-supporting air with oxygen-enriched air will change its combustion characteristics in the furnace. Compared with the original air-assisted combustion, the flame length of oxygen-enriched combustion is significantly shortened, the maximum flame temperature exceeds 1500K, and the flame pulsation is enhanced, which can easily cause the hot carrier gas channel in the low-temperature retorting furnace to overheat, coal ash to slag, and blockage, resulting in uneven airflow and heat distribution in the furnace, fluctuating furnace conditions, and unstable product quality. 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 an oxygen-enriched combustion hot carrier gas generating device and method for a coal low-temperature retort furnace, so as to solve the technical problems that the current internal combustion and internal heating retort furnace directly implements oxygen-enriched combustion, causing the hot carrier gas channel in the low-temperature retort furnace to overheat, coal ash slagging and blockage, resulting in uneven airflow and heat distribution in the furnace, fluctuating furnace conditions, and unstable product quality.
[0005] In order to achieve the above object, the present invention proposes the following technical solutions:
[0006] The invention discloses an oxygen-enriched combustion type hot carrier gas generating device external to a low-temperature coal retorting furnace, comprising a furnace body, a burner and an excess coal gas supplementing gun are fixed on the end surface of one end of the furnace body, a hot carrier gas outlet which can be communicated with the hot carrier gas pipeline of the low-temperature retorting furnace is opened at the other end of the furnace body, a gas distribution ring channel formed by gas distribution bricks is arranged on the side wall at one end of the furnace body, and the excess coal gas supplementing gun is connected with the gas distribution ring channel; a high-energy igniter is also arranged on the side of the furnace body;
[0007] An oxygen-enriched air inlet is provided at the end of the burner, a gas inlet is provided at the side of the burner, and a plurality of coaxial gas channels and oxygen-enriched air channels are provided inside the burner, and the plurality of oxygen-enriched air channels are connected together near the oxygen-enriched air inlet; every two adjacent gas channels are connected at the side of the burner and are connected to a gas inlet; and a swirl blade is provided at the outlet of each gas channel.
[0008] Preferably, four gas channels and four oxygen-enriched air channels are provided in the burner, and two gas inlets are symmetrically arranged on the side of the burner.
[0009] Preferably, a fan-shaped through groove is provided on the front end surface of the air distribution brick, and a fan-shaped hole is provided on the rear end surface.
[0010] Preferably, a fire peep hole is provided on the side of the furnace body.
[0011] Further preferably, the inner lining of the furnace body is formed by symmetrical rings of fan-shaped refractory bricks, and through holes are reserved on the refractory bricks at the locations of the fire peepholes and the high-energy igniters.
[0012] Preferably, the oxygen-enriched combustion type hot carrier gas generating device external to the low-temperature coal retorting furnace is installed horizontally or vertically.
[0013] Preferably, the furnace body is coated with a thermal insulation layer.
[0014] Preferably, the high-energy igniter is a retractable small-flame ignition gun with an integrated flame detector.
[0015] Preferably, a thermometer and a pressure gauge are provided at the hot carrier gas outlet.
[0016] The present invention also discloses an operation method of the above-mentioned oxygen-enriched combustion type hot carrier gas generating device external to the low-temperature coal retorting furnace, comprising:
[0017] Oxygen-enriched air enters the burner from the oxygen-enriched air inlet and is distributed to a number of oxygen-enriched air channels in the burner; coal gas with an equivalent ratio of 1.5 to 5 corresponding to the flow rate of oxygen-enriched air is evenly distributed to each coal gas inlet and enters a number of connected coal gas channels;
[0018] Under the action of the swirl blades at the outlet of the gas channel, the coal gas forms a swirl flow, which is mixed with the oxygen-enriched air jet ejected from the oxygen-enriched air channel in the furnace body; under the action of the high-energy igniter, the coal gas and the oxygen-enriched air ignite and burn;
[0019] The coal gas with an equivalent ratio of 3 to 7 corresponding to the oxygen-enriched air flow enters from the excess coal gas supplement gun, and under the action of the gas distribution ring channel formed by the gas distribution bricks, a uniformly distributed excess coal gas mixed layer is formed around the inner wall of the furnace body;
[0020] The gas obtained after the combustion of the mixed oxygen-enriched air and the coal gas is transported to the hot carrier gas pipeline leading to the low-temperature retort furnace through the hot carrier gas outlet.
[0021] Compared with the prior art, the present invention has the following beneficial effects:
[0022] The present invention discloses an oxygen-enriched combustion type hot carrier gas generating device external to a low-temperature coal retorting furnace, an oxygen-enriched air inlet is provided at the end of the burner, a coal gas inlet is provided at the side of the burner, a plurality of coaxially arranged coal gas channels and oxygen-enriched air channels are provided inside the burner, the plurality of oxygen-enriched air channels are connected together near the oxygen-enriched air inlet, adjacent coal gas channels are connected at the side of the burner and are connected to the coal gas inlet on this side, swirl blades are provided at the outlet of each coal gas channel, so that the coal gas and oxygen-enriched air can enter the furnace body evenly and obtain The mixture is evenly and fully mixed, so that the mixed gas is evenly distributed in the furnace body after combustion, thereby effectively avoiding the situation where the local temperature inside the fire channel is too high; the excess gas replenishing gun disclosed in the present invention, under the action of the gas distribution ring channel formed by the gas distribution bricks, forms a uniformly distributed excess gas mixing layer around the inner wall of the furnace body, while protecting the inner wall of the furnace body from being eroded by the high-temperature flame, regulating the temperature of the hot carrier gas, thereby avoiding overheating of the hot carrier gas channel in the retorting furnace, slagging of coal ash, and blockage, resulting in uneven distribution of airflow and heat in the furnace, fluctuation of furnace conditions, and unstable product quality.
[0023] Furthermore, the gas distribution brick disclosed in the present invention is provided with a fan-shaped through groove on the front end surface to collect the supplementary gas entering from the excess gas supplementary gun, and the rear end surface is provided with a fan-shaped hole to evenly distribute the supplementary gas to the circumference of the furnace. On the one hand, it protects the inner wall of the furnace body from being eroded by the high-temperature flame, and on the other hand, it plays a role in regulating the temperature of the hot carrier gas, thereby avoiding overheating of the hot carrier gas channel in the distillation furnace, slagging of coal ash, and blockage, which lead to uneven airflow and heat distribution in the furnace, fluctuating furnace conditions, and unstable product quality.
[0024] Furthermore, the high-energy igniter disclosed in the present invention is a retractable small flame ignition gun, which can be retracted in time after successful ignition. The high-energy igniter also integrates a flame detector to monitor the flame state in real time. When the flame is extinguished, it can be re-ignited in time to ensure the continuous combustion of oxygen-enriched air and coal gas, thereby avoiding uneven airflow and heat distribution in the furnace, fluctuating furnace conditions, and unstable product quality.
[0025] Furthermore, the present invention provides a thermometer and a pressure gauge at the carrier gas outlet to detect the temperature and pressure of the outlet hot carrier gas, ensuring that the hot carrier gas of rated temperature and pressure enters the hot carrier gas supply pipeline through the outlet, thereby avoiding overheating, slagging and blockage of the hot carrier gas channel in the retorting furnace, resulting in uneven airflow and heat distribution in the furnace, fluctuating furnace conditions and unstable product quality. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Figure 1 It is a front cross-sectional view of an oxygen-enriched combustion type hot carrier gas generating device external to a low-temperature coal retorting furnace of the present invention;
[0027] Figure 2 It is a left end view of the oxygen-enriched combustion type hot carrier gas generating device external to the low-temperature coal retorting furnace of the present invention;
[0028] Figure 3 For along Figure 1 The cross-sectional view along the AA and BB lines; (a) is the AA cross-sectional view; (b) is the BB cross-sectional view;
[0029] Figure 4 It is a schematic diagram of the gas distribution brick structure of the oxygen-enriched combustion type hot carrier gas generating device external to the low-temperature coal retorting furnace of the present invention;
[0030] Figure 5 The present invention is a schematic diagram of the partial structure of the gas distribution bricks of an oxygen-enriched combustion type hot carrier gas generating device external to a low-temperature coal retorting furnace.
[0031] Among them: 1-burner; 2-oxygen-enriched air inlet; 3-oxygen-enriched air channel; 4-gas inlet; 5-gas channel; 6-gas distribution ring; 7-excess gas replenishment gun; 8-gas distribution brick; 9-high-energy igniter; 10-fire peephole; 11-refractory brick; 12-furnace body; 13-insulation layer; 14-hot carrier gas outlet; 15-swirl blades; 16-fan-shaped through grooves; 17-fan-shaped holes. DETAILED DESCRIPTION
[0032] 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.
[0033] 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.
[0034] The present invention is further described in detail below in conjunction with the accompanying drawings:
[0035] See also Figure 1 and Figure 2 The present invention discloses an oxygen-enriched combustion type hot carrier gas generating device external to a low-temperature coal retorting furnace, comprising: a burner 1, an excess gas supply gun 7, a gas distribution brick 8, a high-energy igniter 9, a fire peep hole 10, a refractory brick 11, a furnace body 12, a thermal insulation layer 13, and a hot carrier gas outlet 14. The furnace body 12 is cylindrical, and the refractory brick 11 is used as the inner lining of the furnace body 12. The burner 1 is fixed to the center of the end face of the furnace body 12 through a flange. Two excess gas supply guns 7 are symmetrically arranged on the end face of the furnace body 12, and are connected to the gas distribution ring 6 formed by the gas distribution brick 8. The high-energy igniter 9 and the fire peep hole 10 are arranged on the side of the furnace body 12. The furnace body 12 is covered with a thermal insulation layer 13. The hot carrier gas outlet 14 is connected to the hot carrier gas pipeline leading to the low-temperature retorting furnace, and the hot carrier gas pipeline is strictly insulated.
[0036] Preferably, if Figure 3 As shown, the burner 1 is composed of four annular gas channels 5 and four oxygen-enriched air channels 3, and they are symmetrically distributed with the center of the end of the burner 1 as the center, and each gas channel 5 and oxygen-enriched air channel 3 are coaxially arranged; the four oxygen-enriched air channels 3 converge near the oxygen-enriched air inlet 2, and are connected to the oxygen-enriched air inlet 2 located at the center of the end of the burner 1; two adjacent gas channels 5 are connected at the side of the burner 1, and are respectively connected to the two symmetrically arranged gas inlets 4; swirl blades 15 are respectively arranged at the outlets of the four gas channels 5.
[0037] Preferably, see Figure 4 and Figure 5 The gas distribution annular channel 6 is formed by a circle of fan-shaped gas distribution bricks 8. The front end of the fan-shaped gas distribution brick 8 is provided with a fan-shaped through groove 16 to collect the supplementary gas entering from the excess gas supplementary gun 7, and the rear end is provided with a fan-shaped hole 17 to evenly distribute the supplementary gas to the circumference of the furnace.
[0038] Preferably, the refractory bricks 11 are fan-shaped refractory bricks, which are symmetrically laid around the inner wall of the furnace body 12 , and through holes are reserved at the fire peephole 10 and the high-energy igniter 9 .
[0039] Preferably, the high-energy igniter 9 is a retractable small flame ignition gun and is integrated with a flame detector to monitor the flame state in real time so as to timely re-ignite the flame when it goes out.
[0040] The invention provides a method for using an oxygen-enriched combustion type hot carrier gas generating device external to a low-temperature coal retorting furnace.
[0041] Preferably, oxygen-enriched air with an oxygen enrichment rate of 50% to 100% enters from the oxygen-enriched air inlet 2 and is distributed to four oxygen-enriched air channels 3 in the burner 1; coal gas with an equivalent ratio of 1.5 to 5 corresponding to the oxygen-enriched air flow rate is divided into two streams and enters from two coal gas inlets 4, and is distributed to four coal gas channels 5 in the burner; under the action of the swirl blades 15 at the coal gas channel outlet, a coal gas swirl is formed, which is mixed with the oxygen-enriched air jet ejected from the oxygen-enriched air channel 3, and under the action of the high-energy igniter 9, the coal gas and the oxygen-enriched air ignite and burn.
[0042] Preferably, during the stable operation of the device, the flame state in the furnace is monitored by the flame monitor built into the fire peephole 10 and the high-energy igniter 9 to ensure flame stability. Coal gas with an equivalent ratio of 3 to 7 corresponding to the oxygen-enriched air flow enters from the excess gas supplement gun 7. Under the action of the gas distribution ring 6, a uniformly distributed excess gas mixed layer is formed around the inner wall of the furnace, which protects the inner wall of the furnace from being eroded by the high-temperature flame while regulating the temperature of the hot carrier gas; a thermometer and a pressure gauge are provided at the hot carrier gas outlet 14 to detect the temperature and pressure of the outlet hot carrier gas, and ensure that the hot carrier gas of the rated temperature and pressure enters the hot carrier gas supply pipeline through the outlet, and is transported to the coal low-temperature retorting furnace insulated to provide heat for the coal low-temperature retorting process.
[0043] The following are specific application examples:
[0044] Example: Application to oxygen-enriched combustion transformation of coal low-temperature retorting furnace with annual production of 75,000 tons of semi-coke
[0045] (1) Basic Information
[0046] A coal low-temperature retort furnace with an annual output of 75,000 tons of semi-coke has been built. Air and gas are burned in the furnace to generate high-temperature hot carrier gas to provide heat for the low-temperature retort of coal. A total of 48 gas supply branches are set on both sides of the lower part of the furnace body, supplying air and gas to 48 fire channels respectively. The relevant facilities are fully equipped, including the retort furnace body, combustion-supporting fan, gas fan, raw material preparation (crushing and screening system), feeding system, gas export system, coke removal system, gas purification system, tar collection system, water circulation system, tar pool (tank) and control system. Among them, the return gas flow rate is 4644m 3 / h, air flow rate is 2580m 3 / h.
[0047] (2) Application
[0048] According to the content of the present invention, an oxygen-enriched combustion hot carrier gas generator is built outside the low-temperature coal retort furnace, and 83% oxygen-enriched air is used to burn with coal gas to generate hot carrier gas, which is distributed into the 48 fire channels of the low-temperature retort furnace through the hot carrier gas pipeline to provide heat for the low-temperature coal retort process. The oxygen-enriched air flow rate is 516m 3 / h, all of which enter the furnace (referring to the hot carrier gas generating device) through the oxygen-enriched air inlet at the center of the burner end. The total gas flow rate is 6708m 3 / h, including 3000m 3 / h is evenly divided into two routes to enter through the two gas inlets on the side of the burner, and the remaining 3708m 3 / h coal gas enters from the excess coal gas supplement gun. The oxygen-rich air and coal gas ejected from the burner form a four-flame swirl combustion in the furnace, and the combustion products are mixed with the supplementary coal gas to produce a hot carrier gas of about 1000K, which is transported to the coal low-temperature retorting furnace through the insulation pipeline.
[0049] (3) Application results
[0050] According to the above scheme, low-temperature pyrolysis coal gas and oxygen-enriched air can be stably burned at a large equivalence ratio outside the low-temperature coal pyrolysis furnace, and hot carrier gas with constant temperature is generated to enter the low-temperature pyrolysis furnace, ensuring that the temperature at each fire eye is uniform and does not overheat, avoiding slagging at the fire eye, realizing stable oxygen-enriched combustion low-temperature coal pyrolysis, and improving the quality of coal gas.
[0051] The above contents are only for explaining the technical idea of the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.
Claims
1. An oxygen-enriched combustion hot carrier gas generator external to a low-temperature coal retorting furnace, characterized in that: The invention comprises a furnace body (12), a burner (1) and an excess gas supply gun (7) are fixed on the end surface of one end of the furnace body (12), a hot carrier gas outlet (14) which can communicate with the hot carrier gas pipeline of the low-temperature retorting furnace is provided at the other end of the furnace body (12), a gas distribution ring channel (6) formed by gas distribution bricks (8) is provided on the side wall at one end of the furnace body (12), and the excess gas supply gun (7) is connected to the gas distribution ring channel (6); a high-energy igniter (9) is also provided on the side of the furnace body (12); An oxygen-enriched air inlet (2) is provided at the end of the burner (1), a gas inlet (4) is provided at the side of the burner (1), and a plurality of coaxially arranged gas channels (5) and oxygen-enriched air channels (3) are provided inside the burner (1); the plurality of oxygen-enriched air channels (3) are connected together near the oxygen-enriched air inlet (2); every two adjacent gas channels (5) are connected at the side of the burner and are connected to a gas inlet (4); and a swirl blade (15) is provided at the outlet of each gas channel (5).
2. The oxygen-enriched combustion type hot carrier gas generator external to the low-temperature coal retorting furnace according to claim 1, characterized in that: Four gas channels (5) and four oxygen-enriched air channels are provided in the burner (1), and two gas inlets (4) are symmetrically arranged on the side of the burner (1).
3. The oxygen-enriched combustion type hot carrier gas generator external to the low-temperature coal retorting furnace according to claim 1, characterized in that: The front end surface of the air distribution brick (8) is provided with a fan-shaped through groove (16), and the rear end surface is provided with a fan-shaped hole (17).
4. The oxygen-enriched combustion type hot carrier gas generator external to the low-temperature coal retorting furnace according to claim 1, characterized in that: A fire peek hole (10) is provided on the side of the furnace body (12).
5. The oxygen-enriched combustion type hot carrier gas generator external to the low-temperature coal retorting furnace according to claim 4, characterized in that: The inner lining of the furnace body (12) is formed by symmetrically laying out fan-shaped refractory bricks (11), and through holes are reserved on the refractory bricks at the positions of the fire peephole (10) and the high-energy igniter (9).
6. The oxygen-enriched combustion type hot carrier gas generator external to the low-temperature coal retorting furnace according to claim 1, characterized in that: The oxygen-enriched combustion type hot carrier gas generating device external to the coal low-temperature retort furnace is installed horizontally or vertically.
7. The oxygen-enriched combustion type hot carrier gas generator external to the low-temperature coal retorting furnace according to claim 1, characterized in that: The furnace body (12) is coated with a heat-insulating layer (13).
8. The oxygen-rich combustion type hot carrier gas generator external to a low-temperature coal retorting furnace according to claim 1, characterized in that: The high-energy igniter (9) is a retractable small flame ignition gun and is integrated with a flame detector.
9. The oxygen-rich combustion type hot carrier gas generator external to a low-temperature coal retorting furnace according to claim 1, characterized in that: A thermometer and a pressure gauge are provided at the hot carrier gas outlet (14).
10. The method for operating the oxygen-enriched combustion hot carrier gas generator external to a low-temperature coal retorting furnace according to any one of claims 1 to 9, characterized in that: include: Oxygen-enriched air enters the burner (1) from the oxygen-enriched air inlet (2) and is distributed to a plurality of oxygen-enriched air passages (3) in the burner (1); coal gas with an equivalent ratio of 1.5 to 5 corresponding to the flow rate of the oxygen-enriched air is evenly distributed to each coal gas inlet (4) and enters a plurality of interconnected coal gas passages (5); Under the action of the swirl blades (15) at the outlet of the coal gas passage (5), the coal gas forms a coal gas swirl flow, which is mixed with the oxygen-enriched air jet ejected from the oxygen-enriched air passage (3) in the furnace body (12); under the action of the high-energy igniter (9), the coal gas and the oxygen-enriched air ignite and burn; Coal gas with an equivalent ratio of 3 to 7 corresponding to the flow rate of oxygen-enriched air enters from an excess gas supplement gun (7), and under the action of a gas distribution ring channel (6) formed by gas distribution bricks (8), a uniformly distributed excess gas mixed layer is formed around the inner wall of the furnace body (12); The gas obtained after the mixture of oxygen-enriched air and coal gas is burned is transported to the hot carrier gas pipeline leading to the low-temperature retorting furnace through the hot carrier gas outlet (14).