Carbonization furnace high-calorific-value flue gas utilization system and high-calorific-value flue gas utilization method

Abstract

The invention relates to a system and method for utilizing high-calorific-value smoke of a carbonization furnace in the technical field of fluid sensors, and the system comprises the carbonization furnace, a heat exchanger and a gas pipeline, the carbonization furnace comprises a reaction inner container and a combustion furnace, the multiple gas supply connectors and the multiple air connectors are used for providing natural gas and preheated air for the combustion chamber for mixed combustion heat supply, the heat exchanger comprises a smoke exhaust pipe and an air input pipe, and one end of the smoke exhaust pipe is communicated with the combustion chamber of the combustion furnace. The flue gas exhaust pipe is used for collecting high-calorific-value flue gas in the combustion chamber, and the air input pipe exchanges heat with the flue gas exhaust pipe through the heat exchanger, so that fresh air supplied into the combustion chamber can be preheated, the combustion environment in the combustion chamber is optimized, and the combustion efficiency is improved. And the energy utilization rate of the high-calorific-value flue gas discharged by the carbonization furnace is further improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fluid sensor, in particular to a high-calorific-value flue gas utilization system of carbonization furnace and a high-calorific-value flue gas utilization method. BACKGROUND

[0002] In the production process of negative electrode material, the negative electrode material needs to be carbonized at a temperature above 1000 DEG C. This is known to many people, but some of our users also need to use our pre-carbonization equipment to pre-carbonize the negative electrode material. Pre-carbonization does not require particularly high temperature. Generally, it can meet the requirements below 700 DEG C.

[0003] The existing horizontal roller pre-carbonization furnace has a continuous production process, and the material is continuously fed and carbonized. It can be used for pre-carbonization of negative electrode material. Because the carbonization furnace is constantly rotating during the carbonization process, the raw materials with small particle size can also be uniformly carbonized. The existing pre-carbonization furnace includes a reaction inner container and a combustion furnace, and the combustion furnace is arranged on the surface of the reaction inner container, and the combustion chamber in the combustion furnace and the reaction inner container are independent chambers.

[0004] In the production process of graphite products, the pre-carbonization furnace is an internal combustion type, and the external combustion furnace needs to provide natural gas for combustion all the time to continuously provide a heat source for the reaction inner container. The flue gas generated in the combustion furnace is a kind of high-calorific-value recyclable energy. In order to improve the energy utilization rate of the existing pre-carbonization furnace, it is urgent to develop a carbonization furnace exhaust gas circulation combustion system and a method for recycling exhaust gas, so as to meet the needs of actual use. SUMMARY

[0005] The present application aims to provide a high-calorific-value flue gas utilization system of carbonization furnace and a high-calorific-value flue gas utilization method to solve the above-mentioned defects.

[0006] In order to solve the above technical problems, the present application adopts the following technical scheme:

[0007] The utility model provides a kind of high calorific value flue gas utilization system of carbonization furnace, including carbonization furnace, heat exchanger and gas pipeline, the carbonization furnace includes reaction inner shell and combustion furnace, combustion furnace is covered and is arranged on the surface of reaction inner shell, and the combustion chamber in combustion furnace is independent chamber with reaction inner shell, the middle part of combustion furnace is equipped with several gas supply interfaces and air interface, several gas supply interfaces and air interface are used to provide natural gas and preheated air for combustion chamber to carry out mixed combustion heating, the heat exchanger includes flue gas discharge pipe and air input pipe, one end of flue gas discharge pipe is communicated with the combustion chamber of combustion furnace, flue gas discharge pipe is used to collect high calorific value flue gas in combustion chamber, air input pipe exchanges heat with flue gas discharge pipe by heat exchanger, and the gas pipeline is supplied with natural gas and preheated air to combustion chamber by gas supply interface and air interface respectively.

[0008] In the above description, as a further scheme, one end of the heat exchanger is connected in communication with the flue gas discharge pipe, and the other end of the heat exchanger is provided with a flow collector, the flow collector comprising a first control valve and a first variable frequency fan, the first control valve and the first variable frequency fan being used to control the extraction speed of the flue gas discharge pipe.

[0009] In the above description, as a further scheme, the end of the heat exchanger away from the air input pipe is provided with a preheated air pipeline, the preheated air pipeline and the air input pipe being connected in communication through the heat exchanger, and the preheated air pipeline is connected in communication with the air interface of the combustion furnace.

[0010] In the above description, as a further scheme, the middle part of the gas pipeline is sequentially provided with a total valve, a gas filter, a safety cut-off valve and an air-fuel ratio valve, the end of the gas pipeline is connected with an ignition electrode and a gas nozzle provided in the combustion furnace, and the middle part of the preheated air pipeline is coupled with the gas pipeline through the air-fuel ratio valve.

[0011] In the above description, as a further scheme, the carbonization furnace comprises a preheating section and a pre-carbonization section, the preheating section and the pre-carbonization section being composed of the reaction inner shell and the combustion furnace, the reaction inner shells of the preheating section and the pre-carbonization section being connected end to end, and the combustion furnaces of the preheating section and the pre-carbonization section are connected in communication through a flue gas communication pipe.

[0012] In the above description, as a further scheme, the air interface is provided in the combustion furnace of the pre-carbonization section, and the middle part of the preheated air pipeline is provided with a plurality of second branch pipelines, the second branch pipelines being connected in communication with corresponding air interfaces.

[0013] As a further embodiment of the above description, the end of the combustion furnace is also equipped with a tail gas collector. The tail gas collector and the reaction liner are connected. Both tail gas collectors are equipped with tail gas exhaust pipes. The tail gas exhaust pipes are connected through a filter and a manifold. The other end of the manifold is equipped with a return pipe. The manifold is connected to the combustion furnace in the pre-carbonization section through the return pipe.

[0014] As a further embodiment of the above description, the combustion furnace in the pre-carbonization section is provided with several tail gas interfaces in the middle, and the return pipe is provided with several first diversion pipes connected to the corresponding tail gas interfaces in the middle. The manifold is provided with a second control valve and a second variable frequency fan inside. The second control valve is used to control the closing of the tail gas exhaust pipes of the preheating section and the pre-carbonization section, respectively, and the second variable frequency fan is used to control the conveying of the tail gas exhaust pipes of the preheating section and the pre-carbonization section, respectively.

[0015] A method for utilizing high-calorific-value flue gas, based on the aforementioned high-calorific-value flue gas utilization system for a carbonization furnace, includes the following steps:

[0016] Step 1: Equipment initialization. Natural gas is continuously supplied to the combustion furnace through the gas pipeline. The natural gas is burned in the combustion chamber to produce high-calorific-value flue gas.

[0017] Step 2: High-calorific-value flue gas is collected. The first control valve and the first variable frequency fan in the collector provide negative pressure to the flue gas discharge pipe, and the high-calorific-value flue gas is guided into the heat exchanger through the flue gas discharge pipe. The air inlet pipe and the flue gas discharge pipe are located in the heat exchanger for heat exchange. The preheated air pipe is discharged through the heat exchanger and supplied to the combustion furnace.

[0018] Step 3: Adjusting the ratio of high-calorific-value flue gas to natural gas. The preheated air pipeline is connected to the gas pipeline through an air-fuel ratio valve. The fluid pressure in the preheated air pipeline is controlled by the air-fuel ratio valve to control the flow rate in the gas pipeline.

[0019] Compared with the prior art, the beneficial effects of the present invention are: the high-calorific-value flue gas generated in the combustion chamber is collected at the end of the combustion furnace through the flue gas discharge pipe, and at the same time, the high-calorific-value flue gas can exchange heat with the air in the combustion furnace in the heat exchanger, so that the fresh air supplied to the combustion chamber can be preheated, the combustion environment in the combustion chamber is optimized, and the energy utilization rate of the high-calorific-value flue gas emitted by the carbonization furnace is further improved. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of a high-calorific-value flue gas utilization system for a carbonization furnace as described in this embodiment;

[0021] Figure 2 This is a schematic diagram of the heat exchanger described in this embodiment;

[0022] Figure 3 This is a schematic diagram of the gas pipeline described in this embodiment;

[0023] Figure 4 This is a schematic diagram illustrating the principle of the high-calorific-value flue gas utilization method described in this embodiment;

[0024] In the diagram: 1-Carbonization furnace, 11-Preheating section, 111-Exhaust gas inlet, 112-Air inlet, 12-Pre-carbonization section, 2-Heat exchanger, 21-Flue gas exhaust pipe, 22-Air inlet pipe, 23-Collector, 231-First control valve, 232-First variable frequency fan, 3-Exhaust gas collector, 4-Gas pipeline, 41-Main valve, 42-Gas filter, 43-Safety shut-off valve, 44-Air-fuel proportional valve, 45-Ignition electrode. 46-Gas nozzle, 5-Exhaust gas recirculation pipeline system, 51-Exhaust gas discharge pipeline, 52-Filter, 53-Manifold, 531-Second control valve, 532-Second variable frequency fan, 54-Return pipeline, 541-First branch pipeline, 6-Preheated air pipeline, 61-Second branch pipeline, 62-Pressure connection pipe, 7-Gas supply interface, 8-Reaction liner, 9-Combustion furnace, 91-Combustion chamber, 92-Flue gas connecting pipe. Detailed Implementation

[0025] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0026] For this embodiment, please refer to Figures 1-4 The present invention relates to a high-calorific-value flue gas utilization system for a carbonization furnace, comprising a carbonization furnace 1, a heat exchanger 2, and a gas pipeline 4. The carbonization furnace 1 includes a reaction chamber 8 and a combustion furnace 9. The combustion furnace 9 is disposed on the surface of the reaction chamber 8, and the combustion chamber 91 inside the combustion furnace 9 is an independent chamber from the reaction chamber 8. The combustion furnace 9 has several gas supply interfaces 7 and air interfaces 112 in its middle section, which are used to supply natural gas and preheated air to the combustion chamber 91. The heat exchanger 2, which performs mixed combustion heating, includes a flue gas exhaust pipe 21 and an air inlet pipe 22. One end of the flue gas exhaust pipe 21 is connected to the combustion chamber 91 of the combustion furnace 9. The flue gas exhaust pipe 21 is used to collect the high-calorific-value flue gas in the combustion chamber 91. A preheated air pipe 6 is provided at the end of the heat exchanger 2 away from the air inlet pipe 22. The preheated air pipe 6 is connected to the air inlet pipe 22 through the heat exchanger 2. The preheated air pipe 6 is connected to the air interface 112 of the combustion furnace 9.

[0027] The air inlet pipe 22 exchanges heat with the flue gas outlet pipe 21 through the heat exchanger 2. The gas pipeline 4 and the air inlet pipe 22 supply natural gas and preheated air to the combustion chamber 91 through the gas supply interface 7 and the air interface 112, respectively.

[0028] At the end of the combustion furnace 9, the high-calorific-value flue gas generated in the combustion chamber 91 is collected through the flue gas discharge pipe 21. At the same time, the high-calorific-value flue gas can exchange heat with the air in the combustion furnace 9 in the heat exchanger 2, so that the fresh air supplied to the combustion chamber 91 can be preheated, optimizing the combustion environment in the combustion chamber 91 and further improving the energy utilization rate of the high-calorific-value flue gas emitted by the carbonization furnace 1.

[0029] Specifically, one end of the heat exchanger 2 is connected to the flue gas discharge pipe 21, and the other end of the heat exchanger 2 is provided with a collector 23. The collector 23 includes a first control valve 231 and a first variable frequency fan 232. The first control valve 231 and the first variable frequency fan 232 are used to control the flue gas extraction speed of the flue gas discharge pipe 21. The middle part of the gas pipeline 4 is provided with a main valve 41, a gas filter 5242, a safety shut-off valve 43 and an air-fuel proportional valve 44 in sequence. The end of the gas pipeline 4 is connected to the ignition electrode 45 and the gas nozzle 46 provided inside the combustion furnace 9. The middle part of the preheated air pipeline 6 is connected to the gas pipeline 4 through the air-fuel proportional valve 44.

[0030] The first control valve 231 and the first variable frequency fan 232 can control the extraction speed of flue gas through the flue gas discharge pipe 21, thereby controlling the time that high-calorific-value flue gas remains inside the collector 23, and thus adjusting the temperature of the air discharged from the preheated air pipe 6. At the same time, the preheated air pipe 6 is connected to the natural gas pipe 4 through the air-fuel proportional valve 44. The fluid pressure of the preheated air pipe 6 controls the flow rate of the natural gas pipe 4 through the air-fuel proportional valve 44, realizing the adaptive adjustment of the mutual supply of preheated air and natural gas.

[0031] In a further embodiment, the carbonization furnace 1 includes a preheating section 11 and a precarbonization section 12. The preheating section 11 and the precarbonization section 12 are composed of a reaction liner 8 and a combustion furnace 9. The reaction liner 8 of the preheating section 11 and the precarbonization section 12 are connected end to end. A flue gas connecting pipe 92 is also provided between the combustion furnace 9 of the preheating section 11 and the precarbonization section 12. The combustion furnace 9 of the preheating section 11 and the precarbonization section 12 are connected through the flue gas connecting pipe 92. An air interface 112 is opened in the combustion furnace 9 of the precarbonization section 12. Several second diversion pipes 61 are provided in the middle of the preheating air pipe 6. The second diversion pipes 61 are connected to the corresponding air interface 112.

[0032] The end of the combustion furnace 9 is also provided with a tail gas collector 3. The tail gas collector 3 is connected to the reaction liner 8. Both tail gas collectors 3 are provided with tail gas exhaust pipes 51. The tail gas exhaust pipes 51 are connected through a filter 52 and a manifold 53. The other end of the manifold 53 is provided with a return pipe 54. The manifold 53 is connected to the combustion furnace 9 of the pre-carbonization section 12 through the return pipe 54.

[0033] Since the pre-carbonization section 12 involves the recovery and combustion of exhaust gas in the reaction liner 8, and the combustion of this mixture of natural gas and exhaust gas requires a high temperature environment to maintain stable combustion, the preheating air pipe 6 supplies preheating air to the combustion furnace 9 through several second diversion pipes 61 to mix with the natural gas and exhaust gas. At the same time, the combustion chamber 91 of the pre-carbonization section 12 can be preheated and heated, so that the natural gas and exhaust gas can maintain stable combustion.

[0034] Specifically, the combustion furnace 9 of the pre-carbonization section 12 is provided with several tail gas ports 111 in the middle, and the return pipe 54 is provided with several first diversion pipes 541 connected to the corresponding tail gas ports 111 in the middle. The inside of the manifold 53 is provided with a second control valve 531 and a second variable frequency fan 532. The second control valve 531 is used to control the closing of the tail gas exhaust pipes 51 of the preheating section 11 and the pre-carbonization section 12, respectively. The second variable frequency fan 532 is used to control the delivery of the tail gas exhaust pipes 51 of the preheating section 11 and the pre-carbonization section 12, respectively.

[0035] A method for utilizing high-calorific-value flue gas, based on the aforementioned high-calorific-value flue gas utilization system for a carbonization furnace, includes the following steps:

[0036] Step 1: Equipment initialization. Natural gas is continuously supplied to the combustion furnace 9 through the gas pipeline 4. The natural gas is burned in the combustion chamber 91 to obtain high-calorific-value flue gas.

[0037] Step 2: High-calorific-value flue gas is collected. The first control valve 231 and the first variable frequency fan 232 in the collector 23 provide negative pressure to the flue gas discharge pipe 21, and the high-calorific-value flue gas is guided into the heat exchanger 2 through the flue gas discharge pipe 21. The air inlet pipe 22 and the flue gas discharge pipe 21 are located in the heat exchanger 2 to exchange heat. The preheated air pipe 6 leads the preheated air through the heat exchanger 2 to supply the combustion furnace 9.

[0038] Step 3: Adjusting the ratio of high-calorific-value flue gas to natural gas. The preheated air pipeline 6 is connected to the gas pipeline 4 through the air-fuel ratio valve 44. The fluid pressure of the preheated air pipeline 6 is controlled by the air-fuel ratio valve 44 to control the flow rate of the gas pipeline 4.

[0039] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the inventive concept, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A high-calorific-value flue gas utilization system for a carbonization furnace, characterized in that, include: A carbonization furnace, comprising a reaction liner and a combustion furnace, wherein the combustion furnace is disposed on the surface of the reaction liner and the combustion chamber inside the combustion furnace is an independent chamber from the reaction liner, and the middle part of the combustion furnace is provided with several gas supply interfaces and air interfaces, which are used to supply natural gas and preheated air to the combustion chamber for mixed combustion and heating. A heat exchanger, comprising a flue gas discharge pipe and an air inlet pipe, wherein one end of the flue gas discharge pipe is connected to the combustion chamber of the combustion furnace, and the flue gas discharge pipe is used to collect high-calorific-value flue gas in the combustion chamber, and the air inlet pipe exchanges heat with the flue gas discharge pipe through the heat exchanger; The gas pipeline supplies natural gas and preheated air to the combustion chamber through a gas supply interface and an air input pipe, respectively.

2. The high-calorific-value flue gas utilization system for a carbonization furnace according to claim 1, characterized in that: One end of the heat exchanger is connected to the flue gas discharge pipe, and the other end of the heat exchanger is provided with a collector. The collector includes a first control valve and a first variable frequency fan. The first control valve and the first variable frequency fan are used to control the speed at which the flue gas is extracted by the flue gas discharge pipe.

3. The high-calorific-value flue gas utilization system for a carbonization furnace according to claim 2, characterized in that: The heat exchanger is provided with a preheated air pipe at the end away from the air input pipe. The preheated air pipe is connected to the air input pipe through the heat exchanger and is also connected to the air interface of the combustion furnace.

4. A high-calorific-value flue gas utilization system for a carbonization furnace according to claim 3, characterized in that: The gas pipeline is equipped with a main valve, a gas filter, a safety shut-off valve and an air-fuel proportional valve in sequence in the middle. The end of the gas pipeline is connected to the ignition electrode and gas nozzle inside the combustion furnace. The middle part of the preheating air pipeline is connected to the gas pipeline through the air-fuel proportional valve.

5. A high-calorific-value flue gas utilization system for a carbonization furnace according to any one of claims 1-4, characterized in that: The carbonization furnace includes a preheating section and a precarbonization section, which are composed of a reaction liner and a combustion furnace. The reaction liners of the preheating section and the precarbonization section are connected end to end. A flue gas connecting pipe is also provided between the combustion furnaces of the preheating section and the precarbonization section, and the combustion furnaces of the preheating section and the precarbonization section are connected by the flue gas connecting pipe.

6. A high-calorific-value flue gas utilization system for a carbonization furnace according to claim 5, characterized in that: The air interface is located in the combustion furnace of the pre-carbonization section. Several second diversion pipes are provided in the middle of the preheating air pipe, and the second diversion pipes are connected to the corresponding air interface.

7. A high-calorific-value flue gas utilization system for a carbonization furnace according to claim 5, characterized in that: The end of the combustion furnace is also equipped with a tail gas collector. The tail gas collector and the reaction liner are connected. Both tail gas collectors are equipped with tail gas exhaust pipes. The tail gas exhaust pipes are connected through a filter and a manifold. The other end of the manifold is equipped with a return pipe. The manifold is connected to the combustion furnace of the pre-carbonization section through the return pipe.

8. A high-calorific-value flue gas utilization system for a carbonization furnace according to claim 7, characterized in that: The combustion furnace of the pre-carbonization section is provided with several tail gas interfaces in the middle, and several second diversion pipes are provided in the middle of the return pipe to connect to the corresponding tail gas interfaces. The inside of the manifold is provided with a second control valve and a second variable frequency fan. The second control valve is used to control the closing of the tail gas exhaust pipes of the preheating section and the pre-carbonization section respectively, and the second variable frequency fan is used to control the conveying of the tail gas exhaust pipes of the preheating section and the pre-carbonization section respectively.

9. A method for utilizing high-calorific-value flue gas, characterized in that: A high-calorific-value flue gas utilization system for a carbonization furnace according to any one of claims 1-8 includes the following steps: Step 1: Equipment initialization. Natural gas is continuously supplied to the combustion furnace through the gas pipeline. The natural gas is burned in the combustion chamber to produce high-calorific-value flue gas. Step 2: High-calorific-value flue gas is collected. The first control valve and the first variable frequency fan in the collector provide negative pressure to the flue gas discharge pipe, and the high-calorific-value flue gas is guided into the heat exchanger through the flue gas discharge pipe. The air inlet pipe and the flue gas discharge pipe are located in the heat exchanger for heat exchange. The preheated air pipe is discharged through the heat exchanger and supplied to the combustion furnace. Step 3: Adjusting the ratio of high-calorific-value flue gas to natural gas. The preheated air pipeline is connected to the gas pipeline through an air-fuel ratio valve. The fluid pressure in the preheated air pipeline is controlled by the air-fuel ratio valve to control the flow rate in the gas pipeline.

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