Device and method for introducing coal gas into coke dry quenching system

Abstract

The invention relates to the technical field of coking dry quenching, in particular to a device and a method for introducing coal gas into a dry quenching system. The invention provides a dry quenching system which comprises a dry quenching furnace and a premixer, a plurality of gas input ports of the premixer are provided with at least one coal gas input port, and a mixed gas output port is connected to a plurality of flue input ports through mixed gas pipelines; the input port of the waste heat boiler is connected to the output port of the flue through a first waste heat pipeline, and the first dust remover is used for reducing the concentration of dust input into the waste heat boiler through the first waste heat pipeline; the circulating gas input port of the water supply preheater is connected to the output port through a second waste heat pipeline; and a second dust remover and a circulating fan are arranged on the second waste heat pipeline. By implementing the technical scheme disclosed by the invention, the combustible components of the coal gas and the circulating gas are uniformly mixed and then combusted with the air, so that the mixed circulating gas after combustion is uniform in temperature, and the risk caused by overhigh local temperature is avoided.

Description

Technical Field

[0001] The present disclosure relates to the technical field of coking dry quenching, and in particular to a device and method for introducing coal gas into a dry quenching system. Background Art

[0002] CDQ technology has been widely adopted by coking enterprises. Due to factors such as coke oven equipment maintenance, production restrictions, insufficient market demand for coke, and full CDQ, CDQ equipment often cannot operate at full capacity. Introducing coal gas into the CDQ system for combustion can increase the load of the CDQ system and increase the steam output of the CDQ waste heat boiler, with significant economic benefits. In related technologies, coal gas is directly introduced into the CDQ furnace annular flue, the CDQ furnace outlet flue, or the first dust collector for combustion. In the CDQ system, when the circulating gas that cools the coke exchanges heat with the coke in the cooling section of the CDQ furnace and enters the CDQ furnace annular flue, the concentration of the combustible components CO and H2 in the circulating gas will increase. To ensure the safety of the CDQ system, air is introduced into the CDQ furnace annular flue to burn excess CO and H2 in the circulating gas.

[0003] The conventional requirement for the circulating gas temperature at the CDQ waste heat boiler inlet is ≤980°C. When coal gas is introduced into the CDQ system for combustion, the circulating gas temperature at the CDQ waste heat boiler inlet must also be controlled at ≤980°C. However, the theoretical combustion temperature of coal gas is often higher than 980°C. For example, the combustion temperature of coke oven gas is 1800-2000°C, and the combustion temperature of blast furnace gas is 1400-1500°C. Directly introducing coal gas into the CDQ furnace's annular flue, the CDQ furnace's outlet flue, or the first dust collector for combustion can cause uneven circulating gas temperatures and localized excessive temperatures, increasing the risk of damage to the CDQ furnace, the first dust collector, the waste heat boiler inlet refractory materials, and the waste heat boiler tubes. Summary of the Invention

[0004] The present disclosure aims to solve at least one of the technical problems existing in the prior art or related art.

[0005] To this end, a first aspect of the present disclosure provides a coke dry quenching system, comprising:

[0006] A dry quenching furnace, the dry quenching furnace having a cooling section, a pre-storage section and a flue, the flue having a flue output port and a plurality of flue input ports;

[0007] a premixer, the premixer having a mixed gas output port and a plurality of gas input ports, wherein at least one of the plurality of gas input ports is provided with a coal gas input port, and the mixed gas output port is connected to one of the plurality of flue input ports via a mixed gas pipeline;

[0008] a gas input pipeline connected to the gas input port;

[0009] an air input pipeline, the air input pipeline being connected to the plurality of flue input ports;

[0010] a waste heat boiler, the waste heat boiler having an input port and an output port, the input port being connected to the flue output port via a first waste heat pipeline, the first waste heat pipeline being provided with a first dust collector, the first dust collector being used to reduce the dust concentration in the waste heat boiler inputted via the first waste heat pipeline;

[0011] A feedwater preheater, the feedwater preheater having a circulating gas input port, a venting port, a first circulating gas output port, and a second circulating gas output port, the circulating gas input port being connected to the output port via a second waste heat pipeline, the second waste heat pipeline being provided with a second dust collector and a circulating fan, the circulating fan being provided on a side close to the circulating gas input port;

[0012] a first circulation bypass pipeline, one end of the first circulation bypass pipeline being connected to the first circulation gas output port, and the other end thereof being connected to the gas input port;

[0013] A second circulation bypass pipeline, one end of the second circulation bypass pipeline is connected to the second circulation gas output port, and the other end opposite thereto is connected to the cooling section.

[0014] In a feasible embodiment, a mixed gas introduction device is further included, wherein the mixed gas introduction device includes a mixed gas main pipeline and a plurality of mixed gas branch pipelines, wherein:

[0015] The mixed gas main pipeline has an input end and an output end, the input end is connected to the mixed gas pipeline, and the output end is used to input the mixed gas in the mixed gas pipeline into the plurality of mixed gas branch pipelines;

[0016] The mixed gas branch pipeline is provided with a shut-off valve, and the plurality of mixed gas branch pipelines are respectively connected to the plurality of flue input ports through connecting pipelines.

[0017] In a feasible implementation manner, the connecting pipeline is configured as a three-way pipeline, and the port of the connecting pipeline away from the flue is configured as a spare port.

[0018] In a feasible embodiment, it further includes a regulating valve group, which includes an inlet gas flow regulating valve, an inlet air flow regulating valve, a circulating bypass gas flow regulating valve, and a circulating venting gas flow regulating valve, wherein:

[0019] The imported gas flow regulating valve is provided on the gas input pipeline, and is used to regulate the flow of external gas input into the premixer;

[0020] The imported air flow regulating valve is provided on the air input pipeline, and is used to regulate the flow of external air input into the flue;

[0021] The circulating bypass air flow regulating valve is provided on the first circulating bypass pipeline, and the circulating bypass air flow regulating valve is used to regulate the circulating air flow rate input from the feedwater preheater to the premixer;

[0022] The circulating gas flow regulating valve is used to adjust the circulating gas discharge amount of the discharge port.

[0023] In a feasible embodiment, it also includes a sampling and analysis device, which includes a gas sampling device and a circulating gas sampling analyzer. The gas sampling device is connected to the gas input pipeline, and the gas sampling device is used to detect the volume fraction of the combustible components of the input gas. The circulating gas sampling analyzer is connected to the second circulation bypass pipeline, and the circulating gas sampling analyzer is used to monitor the volume fraction of the combustible components in the circulating gas output by the feed water preheater.

[0024] In a feasible embodiment, a flow detection device is further included, wherein the flow detection device includes an inlet gas flow meter, an inlet air flow meter, a circulating bypass gas flow meter and a circulating vented gas flow meter, wherein:

[0025] The imported gas flow meter is connected to the gas input pipeline, and is used to detect the gas flow of the external gas before it passes through the imported gas flow regulating valve;

[0026] The inlet air flow meter is connected to the air input pipeline, and the inlet air flow meter is used to detect the air flow of the external air before passing through the inlet air flow regulating valve;

[0027] The circulating bypass air flow meter is connected to the first circulating bypass pipeline, and the circulating bypass air flow meter is used to detect the circulating air flow rate before the circulating air passes through the circulating bypass air flow regulating valve;

[0028] The circulating vent gas flow meter is used to detect the venting amount of the circulating gas of the feed water preheater.

[0029] In a second aspect of the present disclosure, a method for introducing coal gas into a dry quenching system applied to the dry quenching system of the first aspect of the present disclosure is provided, comprising:

[0030] Circulation premixing: the flow rate of the external gas input into the premixer is determined based on the combustible component analysis data. The circulating bypass gas output from the feedwater preheater is mixed with the external gas in the premixer to form premixed circulating bypass gas. The premixed circulating bypass gas is introduced into the flue of the CDQ furnace through the mixed gas pipeline;

[0031] Flue mixing, the premixed circulating bypass gas introduced into the flue is mixed for the second time with the high-temperature inert circulating gas from the CDQ furnace cooling section in the flue to form mixed circulating gas, and the mixed bypass gas is made to reach a first preset temperature;

[0032] Air introduction, introducing air into the flue to mix with the mixed circulating gas in the flue, and reducing the combustible components in the mixed circulating gas to a set threshold before the mixed circulating gas flows out of the CDQ furnace;

[0033] Waste heat recovery: the mixed circulating gas enters the first dust collector through the dry quenching furnace outlet for further combustion, and the first dust collector maintains the first preset temperature before entering the waste heat boiler;

[0034] Waste heat circulation: After the waste heat boiler reduces the temperature of the mixed circulating gas to a second preset temperature, the mixed circulating gas is dedusted by the second dust collector and then enters the feed water preheater for heat exchange to form the circulating bypass gas. After the heat exchange, the bypass circulating gas enters the cooling section of the dry quenching furnace through the second circulating bypass pipeline to cool the coke, and enters the premixer through the first circulating bypass pipeline to wait for mixing with the external coal gas, and continues to circulate according to the above steps.

[0035] In a feasible embodiment, in the circulating premixing step, the external coal gas is introduced when the circulating gas temperature at the outlet of the first dust collector is ≥700°C.

[0036] In a feasible embodiment, in the step of recycling the waste heat, the circulating bypass gas is sampled online during the process of the circulating bypass gas passing through the second circulating bypass pipeline and entering the cooling section of the dry quenching furnace. The circulating bypass gas is sampled and analyzed, and when the volume fraction of the combustible component CO is greater than 6% and the volume fraction of H2 is greater than 3% in the analysis data, the introduction of the coal gas is stopped.

[0037] In a feasible implementation manner, the first preset temperature is set to 900°C to 980°C, and the second preset temperature is set to 160°C to 180°C.

[0038] The above description is only an overview of the technical solution provided by the present disclosure. In order to more clearly understand the technical means of the present disclosure, it can be implemented in accordance with the contents of the specification. In order to make the above and other features and effects of the present disclosure more obvious and easy to understand, the following specifically lists the implementation methods of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0040] In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0041] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the exemplary embodiments below. The accompanying drawings are for illustration purposes only and are not to be considered limiting of the present application. Throughout the accompanying drawings, the same reference symbols denote the same components. In the accompanying drawings:

[0042] Figure 1 A schematic diagram of the structure of the present disclosure;

[0043] Figure 2 This is a schematic structural diagram of the mixed gas introduction device disclosed in the present invention;

[0044] Figure 3 Schematic diagram of the structure of the connecting pipeline disclosed in the present invention.

[0045] in, Figures 1 to 3 The corresponding relationship between the reference numerals and component names is as follows:

[0046] 100-mixed gas pipeline; 200-gas input pipeline; 300-air input pipeline; 400-first waste heat pipeline; 500-second waste heat pipeline; 600-first circulation bypass pipeline; 700-second circulation bypass pipeline; 800-discharge pipeline;

[0047] 1- Premixer; 2- Mixed gas introduction device; 22- Mixed gas main line; 23- Mixed gas branch line; 24- Connecting pipeline; 3- CDQ furnace; 31- Cooling section; 32- Pre-storage section; 33- Flue; 4- First dust collector; 5- Waste heat boiler; 6- Second dust collector; 7- Circulating fan; 8- Feed water preheater; 9- Inlet gas flow regulating valve; 10- Circulating bypass gas flow regulating valve; 11- Shut-off valve; 12- Inlet air flow regulating valve; 13- Circulating vent gas flow regulating valve; 14- Gas sampling device; 15- Inlet gas flowmeter; 16- Circulating bypass gas flowmeter; 17- Inlet air flowmeter; 18- Circulating vent gas flowmeter; 19- First dust collector outlet thermometer; 20- Pressure alarm device; 21- Circulating gas sampling analyzer. DETAILED DESCRIPTION

[0048] In order to more clearly understand the above-mentioned objectives, features and advantages of the present disclosure, the scheme of the present disclosure will be further described below. It should be noted that the embodiments of the present disclosure and the features therein can be combined with each other in the absence of conflict.

[0049] In the following description, many specific details are set forth to facilitate a full understanding of the present disclosure, but the present disclosure may also be implemented in other ways different from those described herein; it is obvious that the embodiments in the specification are only part of the embodiments of the present disclosure, rather than all of the embodiments.

[0050] At present, CDQ technology has been widely adopted by coking enterprises. Due to factors such as coke oven equipment maintenance, production restrictions, insufficient market demand for coke, and full CDQ, CDQ equipment often cannot operate at full capacity. Introducing coal gas into the CDQ system for combustion can increase the load of the CDQ system and increase the steam production of the CDQ waste heat boiler, with significant economic benefits. In related technologies, coal gas is directly introduced into the CDQ furnace annular flue, the CDQ furnace outlet flue, or the dust collector for combustion. In the CDQ system, when the circulating gas that cools the coke exchanges heat with the coke in the CDQ furnace cooling section and enters the CDQ furnace annular flue, the concentration of the combustible components CO and H2 in the circulating gas will increase. To ensure the safety of the CDQ system, air is introduced into the CDQ furnace annular flue to burn excess CO and H2 in the circulating gas.

[0051] The conventional requirement for the circulating gas temperature at the CDQ waste heat boiler inlet is ≤980°C. When coal gas is introduced into the CDQ system for combustion, the circulating gas temperature at the CDQ waste heat boiler inlet must also be controlled at ≤980°C. However, the theoretical combustion temperature of coal gas is often higher than 980°C. For example, the combustion temperature of coke oven gas is 1800-2000°C, and the combustion temperature of blast furnace gas is 1400-1500°C. Directly introducing coal gas into the CDQ furnace's annular flue, the CDQ furnace's outlet flue, or the first dust collector for combustion can cause uneven circulating gas temperatures and localized excessive temperatures, increasing the risk of damage to the CDQ furnace, the first dust collector, the waste heat boiler inlet refractory materials, and the waste heat boiler tubes.

[0052] In addition, the gas inlet location was not chosen properly. The gas inlet was not close enough to the waste heat boiler. If the gas was introduced into the dust collector, it might cause incomplete combustion of the combustible gas and cause it to continue burning at the boiler inlet.

[0053] Based on this, an embodiment of the present disclosure provides a dry quenching system, in which the introduced coal gas is premixed with the circulating bypass gas in the premixer, and then mixed for the second time with the high-temperature inert circulating gas from the cooling section of the dry quenching furnace in the annular flue of the dry quenching furnace. The combustible components of the coal gas and the circulating gas are evenly mixed and then burned with air, so that the temperature of the mixed circulating gas after combustion is uniform, avoiding the risk of local excessive temperature; the coal gas is introduced from the side close to the first dust collector, which increases the distance from the inlet of the waste heat boiler, increases the coal gas combustion time, and ensures that the coal gas can be fully burned.

[0054] The following describes the dry quenching system in detail through a specific embodiment:

[0055] Reference Figures 1 to 3 As shown, in a first aspect of the present disclosure, a dry coke quenching system is provided, comprising a dry quenching furnace 3, the dry quenching furnace 3 having a cooling section 31, a pre-storage section 32 and a flue 33, the flue 33 having a flue output port and a plurality of flue input ports; a premixer 1, the premixer 1 having a mixed gas output port and a plurality of gas input ports, the plurality of gas input ports being provided with at least one coal gas input port, the mixed gas output port being connected to one of the plurality of flue input ports via a mixed gas pipeline 100; a coal gas input pipeline 200, the coal gas input pipeline 200 being connected to the coal gas input port; an air input pipeline 300, the air input pipeline 300 being connected to the plurality of flue input ports; a waste heat boiler 5, the waste heat boiler 5 having an input port and an output port, the input port being connected to the flue output port via a first waste heat pipeline 400, the first waste heat pipeline 400 being provided with a gas input port; There is a first dust collector 4, which is used to reduce the dust concentration in the waste heat boiler 5 input by the first waste heat pipeline 400; a feed water preheater 8, which has a circulating gas input port, a venting port, a first circulating gas output port and a second circulating gas output port, and the circulating gas input port is connected to the output port through the second waste heat pipeline 500. The second waste heat pipeline 500 is provided with a second dust collector 6 and a circulating fan 7, and the circulating fan 7 is arranged on the side close to the circulating gas input port; a first circulating bypass pipeline 600, one end of the first circulating bypass pipeline 600 is connected to the first circulating gas output port, and the other end is connected to the gas input port; a second circulating bypass pipeline 700, one end of the second circulating bypass pipeline 700 is connected to the second circulating gas output port, and the other end is connected to the cooling section 31.

[0056] The dry quenching furnace 3 disclosed in the present invention has a cooling section 31, a pre-storage section 32 and a flue 33, wherein the connection relationship and positional relationship of the cooling section 31, the pre-storage section 32 and the flue 33 are conventional settings of existing dry quenching furnaces, and will not be described in detail in this disclosure. The premixer 1 disclosed in the present invention has multiple gas input ports and at least one gas input port must be provided for inputting external gas. Multiple gas input ports can also be provided, and the number of gas input ports can be adaptively selected according to the actual working conditions. The remaining gas input ports can be provided as input ports for circulating bypass gas in the feed water preheater 8. One or more gas input ports connected to the feed water preheater 8 can be provided, and can be adaptively set according to the maximum gas flow requirements. When the coal gas is introduced, it is premixed with the circulating bypass gas in the premixer 1, and then mixed for the second time with the high-temperature inert circulating gas at the outlet of the cooling section 31 of the dry quenching furnace 3 in the annular flue 33 of the dry quenching furnace 3. The combustible components of the coal gas and the circulating gas are evenly mixed and then burned with air, so that the temperature of the mixed circulating gas after combustion is uniform, avoiding the risk of local excessive temperature. The circulating bypass gas is formed by the feed water preheater 8 through the flue 33 through the first dust collector 4, the waste heat boiler 5, and the second dust collector 6. The circulating bypass gas is intended to reduce the combustible components of the flue gas in the flue 33, thereby reducing the flue gas temperature in the flue 33. When the equipment is not circulating, the circulating bypass gas can be directly introduced into the premixer 1. After the system of the present disclosure is circulated as a whole, the circulating bypass gas can be produced autonomously. It should be noted that both the flue 33 and the first dust collector 4 can extend the outflow time of the flue gas so that the combustible components in the flue gas can be fully burned, thereby avoiding the accumulation of coal gas content in the flue gas and causing system failure.

[0057] In some embodiments, a mixed gas introduction device 2 is also included, which includes a mixed gas main line 22 and multiple mixed gas branch lines 23, wherein the mixed gas main line 22 has an input end and an output end, the input end is connected to the mixed gas line 100, and the output end is used to allow the mixed gas in the mixed gas line 100 to be input into the multiple mixed gas branch lines 23; a shut-off valve 11 is provided on the mixed gas branch line 23, and the multiple mixed gas branch lines 23 are respectively connected to multiple flue input ports through connecting lines 24.

[0058] In this embodiment, the mixed gas introduction device 2 disclosed in the present invention includes a mixed gas main line 22 and multiple mixed gas branch lines 23, wherein the mixer main line 22 can use a pipeline structure such as a diverter bar and a bus bar to realize the gas input to multiple mixer branch lines 23, and the number of them can be flexibly used according to the size of the circulating bypass gas. The connection line 24 is connected to multiple flue input ports to avoid modification of the dry quenching furnace 3 and its refractory lining, and is convenient for implementation. Furthermore, the connection line 24 is set as a three-way pipe, and the port of the connection line 24 away from the flue 33 is set as a spare port. For example, Figure 3As shown, the connecting pipe 24 is configured as a T-shaped tee pipe, and the spare port is sealed with a flange cover for maintenance, so as to facilitate maintenance of the connecting pipe 24 and extend its online cycle; when the CDQ furnace itself is running at full load and does not need to introduce gas, the spare port is used to replace the CDQ furnace original circulation bypass gas introduction inspection hole cover and plug cover.

[0059] In some embodiments, a regulating valve group is also included, which includes an inlet gas flow regulating valve 9, an inlet air flow regulating valve 12, a circulating bypass air flow regulating valve 10 and a circulating venting air flow regulating valve 13, wherein the inlet gas flow regulating valve 9 is arranged on the gas input pipeline 200, and the inlet gas flow regulating valve 9 is used to regulate the flow of the external gas input to the premixer 1; the inlet air flow regulating valve 12 is arranged on the air input pipeline 300, and the inlet air flow regulating valve 12 is used to regulate the flow of the external air input to the flue 33; the circulating bypass air flow regulating valve 10 is arranged on the first circulating bypass pipeline 600, and the circulating bypass air flow regulating valve 10 is used to regulate the circulating gas flow input from the feed water preheater 8 to the premixer 1; the circulating venting air flow regulating valve 13 is used to regulate the circulating gas discharge amount of the venting port.

[0060] In this embodiment, the inlet gas flow regulating valve 9, the inlet air flow regulating valve 12, the circulating bypass gas flow regulating valve 10 and the circulating vent gas flow regulating valve 13 can adjust the gas flow of the pipelines to which they belong, and further finely control the volume fraction of the combustible components in the flue gas, so that its combustion efficiency is adjusted, thereby controlling the flue gas temperature.

[0061] In some embodiments, a sampling and analysis device is further included. The sampling and analysis device includes a gas sampling device 14 and a circulating gas sampling and analyzer 21. The gas sampling device 14 is connected to the gas input pipeline 200 and is used to detect the volume fraction of combustible components in the input gas. The circulating gas sampling and analyzer 21 is connected to the second circulating bypass pipeline 700 and is used to monitor the volume fraction of combustible components in the circulating gas input and output by the feedwater preheater 8. Specifically, the gas sampling device 14 and the circulating gas sampling and analyzer 21 are both conventional analysis devices used in coking enterprises.

[0062] In this embodiment, to ensure the safety of the CDQ system, a circulating gas sampling and analysis device 21 performs online sampling and analysis. The qualified circulating gas composition must meet the requirements of a combustible CO volume fraction ≤6%, an H2 volume fraction ≤3%, and the remainder primarily consisting of inert components N2, H2O, and CO2. Gas introduction is stopped if the CO volume fraction is greater than 6% or the H2 volume fraction is greater than 3%. The gas sampling device 14 regularly samples and analyzes the external gas, accurately calculating the gas flow rate introduced into the premixer 1 and facilitating refined control of the overall flue gas temperature in the present disclosure.

[0063] In some embodiments, a flow detection device is also included, which includes an inlet gas flowmeter 15, an inlet air flowmeter 17, a circulation bypass gas flowmeter 16 and a circulation vent gas flowmeter 18, wherein the inlet gas flowmeter 15 is connected to the gas input pipeline 200, and the inlet gas flowmeter 15 is used to detect the gas flow of the external gas before passing through the inlet gas flow control valve 9; the inlet air flowmeter 17 is connected to the air input pipeline 300, and the inlet air flowmeter 17 is used to detect the air flow of the external air before passing through the inlet air flow control valve 12; the circulation bypass gas flowmeter 16 is connected to the first circulation bypass pipeline 600, and the circulation bypass gas flowmeter 16 is used to detect the circulation gas flow before the circulation gas passes through the circulation bypass gas flow control valve 10; the circulation vent gas flowmeter 18 is used to detect the discharge amount of the circulation gas of the feed water preheater 8. In this embodiment, the inlet gas flowmeter 15, the inlet air flowmeter 17, the circulating bypass gas flowmeter 16 and the circulating vented gas flowmeter 18 can detect the input flow of the pipelines to control the output flow.

[0064] In some embodiments, the present disclosure further provides a venting pipeline 800 , a circulating venting gas flow meter 18 and a circulating venting gas flow regulating valve 13 are provided in the venting pipeline 800 , and a venting port of the venting pipeline 800 is connected to a desulfurization and dust removal device.

[0065] In some embodiments, the pre-storage section 32 of the present disclosure is further provided with a CDQ pre-pressure section pressure gauge 20, which is used to display the pressure in the pre-storage section 32 and to provide an alarm when the pressure exceeds a set pressure threshold. To ensure stable pressure in the pre-storage section of the CDQ furnace 3, a pressure regulation relationship is maintained between the CDQ pre-storage section pressure gauge 20 and the circulating vent gas flow control valve 13. A first dust collector outlet thermometer 19 is provided at the outlet of the first dust collector 4 of the present disclosure. The detected temperature signal is sent to the circulating bypass gas flow control valve 10, which adjusts the pressure of the circulating bypass gas flow control valve 10 when the circulating gas temperature is too high or too low.

[0066] The flow detection device, sampling and analysis device and regulating valve group in the embodiment of the present disclosure can all be responsive and regulated by means of electrical signal connection, that is, the inlet gas pipeline is provided with an inlet gas flow meter 15 and an inlet gas flow regulating valve 9, the circulating bypass gas pipeline is provided with a circulating bypass gas flow meter 16 and a circulating bypass gas flow regulating valve 10, the inlet air pipeline is provided with an inlet air flow meter 17 and an inlet air flow regulating valve 12, the circulating vent gas pipeline is provided with a circulating vent gas flow meter 18 and a circulating vent gas flow regulating valve 13, the inlet air, circulating bypass gas and circulating vent gas flow rates are regulated according to the inlet gas flow rate, the circulating bypass gas and the circulating vent gas flow rates are regulated according to the inlet gas flow rate, and the circulating bypass gas flow rate is regulated according to the circulating bypass gas flow rate. The flow rates detected by the air flow meter 16, the inlet air flow meter 17, and the circulating vent gas flow meter 18 are proportionally regulated to the flow rate detected by the inlet coal gas flow meter 15. A primary dust collector outlet thermometer 19 is installed at the primary dust collector outlet, sending the detected temperature signal to the circulating bypass air flow control valve 10. When the circulating gas temperature is too high or too low, the valve 10 is adjusted to ensure that the circulating gas temperature at the inlet of the waste heat boiler 5 is controlled between 900 and 980°C. To ensure the stability of the pre-storage section pressure of the CDQ furnace 3, a pressure regulation relationship is maintained between the pre-storage section pressure gauge 20 of the CDQ furnace and the circulating vent gas flow control valve 13. It should be noted that the electrical signal connection and regulation logic of the above-mentioned devices and valve groups are optional, and the operator can also perform independent adjustments of each component through data analysis.

[0067] In a second aspect of the present disclosure, a method for introducing coal gas into a dry coke quenching system is provided, which is applied to the dry coke quenching system of the first aspect of the present disclosure, comprising:

[0068] Circulation premixing: The flow rate of the external gas input into the premixer 1 is determined based on the combustible component analysis data. The circulating bypass gas output from the feedwater preheater 8 is mixed with the external gas in the premixer 1 to form premixed circulating bypass gas. The premixed circulating bypass gas is introduced into the flue 33 of the CDQ furnace 3 through the mixed gas pipeline 100;

[0069] Flue mixing: the premixed circulating bypass gas introduced into the flue 33 is mixed for the second time with the high-temperature inert circulating gas from the cooling section 31 of the CDQ furnace 3 in the flue 33 to form a mixed circulating gas, and the mixed bypass gas is made to reach a first preset temperature;

[0070] Air introduction: air is introduced into the flue 33 to mix with the mixed circulating gas in the flue 33, and the combustible components in the mixed circulating gas are reduced to a set threshold before flowing out of the dry quenching furnace 3;

[0071] Waste heat recovery, the mixed circulating gas enters the first dust collector 4 through the outlet of the dry quenching furnace 3 for further combustion, and the first dust collector 4 maintains the mixed circulating gas at a first preset temperature before entering the waste heat boiler 5;

[0072] In the waste heat circulation, the waste heat boiler 5 reduces the temperature of the mixed circulating gas to the second preset temperature, and then the mixed circulating gas is dedusted by the second dust collector 6 and enters the feed water preheater 8 for heat exchange to form circulating bypass gas. The bypass circulating gas after heat exchange enters the cooling section 31 of the dry quenching furnace 3 through the second circulating bypass pipeline 700 to cool the coke, and enters the premixer 1 through the first circulating bypass pipeline 600 to wait for mixing with the external coal gas, and continues to circulate according to the above steps.

[0073] Specifically, the external coal gas disclosed herein can be regularly sampled and analyzed. The metered amount of the introduced coal gas is determined based on the analysis results and then enters the premixer 1. The circulating bypass gas output from the feedwater preheater 8 is mixed with the external coal gas within the premixer 1, and after dilution, the concentration of the combustible components in the coal gas is initially reduced to form premixed circulating bypass gas. The premixed circulating bypass gas is then introduced into the flue 33 of the CDQ furnace 3 via the mixed gas pipeline 100. The premixed circulating bypass gas introduced into the annular flue 33 of the CDQ furnace 3 is then mixed and diluted a second time with the high-temperature inert circulating gas from the cooling section of the CDQ furnace 3 within the annular flue 33 of the CDQ furnace 3, further reducing the concentration of the combustible components and achieving uniform mixing of the coal gas and the circulating gas.

[0074] In the air introduction step disclosed in the present invention, the air enters the annular flue 33 of the dry quenching furnace 33 after the flow rate is calculated, and is mixed with the mixed circulating gas in the annular flue 33, and most of the combustible components in the mixed circulating gas are burned and then flow out of the dry quenching furnace. The mixed circulating gas in which most of the combustible components output through the flue 33 are burned is input into the first dust collector 4, and the unburned combustible components are further burned to the first preset temperature in the first dust collector 4, and enter the waste heat boiler 5 for waste heat recovery after the outlet temperature of the first dust collector 4 is tested to be qualified. Furthermore, the first preset temperature is set to 900°C to 980°C. The circulating gas is in the temperature range of 900°C to 980°C to ensure efficient heat exchange of the boiler. If the temperature is too low, the heat recovery is insufficient; the temperature exceeds 980°C and exceeds the temperature that the boiler tube material can withstand.

[0075] After being recovered by the waste heat boiler 5, the temperature drops to the second preset temperature inside the waste heat boiler 5 and flows out of the waste heat boiler 5. After being dusted by the secondary dust collector 6 and pressurized by the circulating fan 7, it enters the feed water preheater 8 and exchanges heat with the deoxygenated feed water to 130℃±5℃ ， Part of the circulating bypass gas generated after heat exchange, after sampling and analysis, passes into the cooling section of CDQ furnace 3 to cool the coke. Part of the circulating bypass gas enters premixer 1 and then into the annular flue of CDQ furnace 3 to adjust the circulating gas temperature, controlling the circulating gas temperature at the inlet of waste heat boiler 5 to ≤980°C. Excess circulating gas after combustion passes through circulating vent gas flowmeter 18 and circulating vent gas flow control valve 13 and enters the desulfurization and dust removal equipment for purification before being discharged to meet the standards. These steps complete the first cycle of flue gas after the CDQ furnace introduces coal gas.

[0076] Through the above steps, the whole process of introducing coal gas for mixing and dilution, combustion, circulating gas temperature control, circulating gas waste heat utilization, and circulating gas release meeting the standards after combustion is completed.

[0077] In some embodiments, during the circulating premixing step, external coal gas is introduced when the circulating gas temperature at the outlet of the first dust collector 4 is ≥700°C. Because the combustible components in the circulating gas have an ignition temperature of 644°C to 658°C for CO, 580°C to 590°C for H2, and 650°C to 670°C for CH4, the temperature is set to ≥700°C to ensure combustion of the combustible components.

[0078] In some embodiments, during the waste heat recycling step, online sampling of the circulating bypass gas is performed as the circulating bypass gas enters the cooling section 31 of the CDQ furnace 3 through the second circulating bypass pipeline 700. After sampling and analysis of the circulating bypass gas, if the analyzed data indicates a combustible component CO volume fraction greater than 6% and a H2 volume fraction greater than 3%, the introduction of coal gas is stopped. When the combustible component CO volume fraction exceeds 6% and the H2 volume fraction exceeds 3%, there is a risk of explosion.

[0079] In the present disclosure, the terms "first", "second", and "third" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance; the term "plurality" refers to two or more, unless otherwise expressly defined. Terms such as "installed", "connected", "connected", and "fixed" should be understood in a broad sense. For example, "connected" can mean a fixed connection, a detachable connection, or an integral connection; "connected" can mean a direct connection or an indirect connection through an intermediate medium. For those skilled in the art, the specific meanings of the above terms in the present disclosure can be understood according to the specific circumstances.

[0080] In the description of the present disclosure, it is to be understood that the terms "up", "down", "left", "right", "front", "back", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present disclosure and simplifying the description, rather than indicating or implying that the device or unit referred to must have a specific direction, be constructed and operated in a specific direction, and therefore, cannot be understood as a limitation on the present disclosure.

[0081] Throughout this specification, terms such as "one embodiment," "some embodiments," and "specific embodiments" mean that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0082] The above are merely preferred embodiments of the present disclosure and are not intended to limit the present disclosure. Those skilled in the art will readily appreciate that various modifications and variations of the present disclosure are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present disclosure shall be included within the scope of protection of the present disclosure.

Claims

1. A dry quenching system, characterized in that: include: A dry quenching furnace, the dry quenching furnace having a cooling section, a pre-storage section and a flue, the flue having a flue output port and a plurality of flue input ports; a premixer, the premixer having a mixed gas output port and a plurality of gas input ports, wherein at least one of the plurality of gas input ports is provided with a coal gas input port, and the mixed gas output port is connected to one of the plurality of flue input ports via a mixed gas pipeline; a gas input pipeline connected to the gas input port; an air input pipeline, the air input pipeline being connected to the plurality of flue input ports; a waste heat boiler, the waste heat boiler having an input port and an output port, the input port being connected to the flue output port via a first waste heat pipeline, the first waste heat pipeline being provided with a first dust collector, the first dust collector being used to reduce the dust concentration in the waste heat boiler inputted via the first waste heat pipeline; A feedwater preheater, the feedwater preheater having a circulating gas input port, a venting port, a first circulating gas output port, and a second circulating gas output port, the circulating gas input port being connected to the output port via a second waste heat pipeline, the second waste heat pipeline being provided with a second dust collector and a circulating fan, the circulating fan being provided on a side close to the circulating gas input port; a first circulation bypass pipeline, one end of the first circulation bypass pipeline being connected to the first circulation gas output port, and the other end thereof being connected to the gas input port; A second circulation bypass pipeline, one end of the second circulation bypass pipeline is connected to the second circulation gas output port, and the other end opposite thereto is connected to the cooling section.

2. The dry quenching system according to claim 1, characterized in that: It also includes a mixed gas introduction device, which includes a mixed gas main pipeline and a plurality of mixed gas branch pipelines, wherein: The mixed gas main pipeline has an input end and an output end, the input end is connected to the mixed gas pipeline, and the output end is used to input the mixed gas in the mixed gas pipeline into the plurality of mixed gas branch pipelines; The mixed gas branch pipeline is provided with a shut-off valve, and the plurality of mixed gas branch pipelines are respectively connected to the plurality of flue input ports through connecting pipelines.

3. The dry quenching system according to claim 1, characterized in that: The connecting pipeline is configured as a three-way pipeline, and the port of the connecting pipeline away from the flue is configured as a spare port.

4. The dry quenching system according to claim 1, characterized in that: It also includes a regulating valve group, which includes an inlet gas flow regulating valve, an inlet air flow regulating valve, a circulating bypass gas flow regulating valve, and a circulating venting gas flow regulating valve, wherein: The imported gas flow regulating valve is provided on the gas input pipeline, and is used to regulate the flow of external gas input into the premixer; The imported air flow regulating valve is provided on the air input pipeline, and is used to regulate the flow of external air input into the flue; The circulating bypass air flow regulating valve is provided on the first circulating bypass pipeline, and the circulating bypass air flow regulating valve is used to regulate the circulating air flow rate input from the feedwater preheater to the premixer; The circulating gas flow regulating valve is used to adjust the circulating gas discharge amount of the discharge port.

5. The dry quenching system according to claim 4, characterized in that: It also includes a sampling and analysis device, which includes a gas sampling device and a circulating gas sampling analyzer. The gas sampling device is connected to the gas input pipeline, and the gas sampling device is used to detect the volume fraction of the combustible components in the input gas. The circulating gas sampling analyzer is connected to the second circulation bypass pipeline, and the circulating gas sampling analyzer is used to monitor the volume fraction of the combustible components in the circulating gas input and output of the feed water preheater.

6. The dry quenching system according to claim 4 or 5, characterized in that: It also includes a flow detection device, which includes an inlet gas flow meter, an inlet air flow meter, a circulating bypass gas flow meter and a circulating vented gas flow meter, wherein: The imported gas flow meter is connected to the gas input pipeline, and is used to detect the gas flow of the external gas before it passes through the imported gas flow regulating valve; The inlet air flow meter is connected to the air input pipeline, and the inlet air flow meter is used to detect the air flow of the external air before passing through the inlet air flow regulating valve; The circulating bypass air flow meter is connected to the first circulating bypass pipeline, and the circulating bypass air flow meter is used to detect the circulating air flow rate before the circulating air passes through the circulating bypass air flow regulating valve; The circulating vent gas flow meter is used to detect the venting amount of the circulating gas of the feed water preheater.

7. A method for introducing coal gas into a dry quenching system, characterized in that: include: Circulation premixing: the flow rate of the external gas input into the premixer is determined based on the combustible component analysis data. The circulating bypass gas output from the feedwater preheater is mixed with the external gas in the premixer to form premixed circulating bypass gas. The premixed circulating bypass gas is introduced into the flue of the CDQ furnace through the mixed gas pipeline; Flue mixing, the premixed circulating bypass gas introduced into the flue is mixed for the second time with the high-temperature inert circulating gas from the CDQ furnace cooling section in the flue to form mixed circulating gas, and the mixed bypass gas is made to reach a first preset temperature; Air introduction, introducing air into the flue to mix with the mixed circulating gas in the flue, and reducing the combustible components in the mixed circulating gas to a set threshold before the mixed circulating gas flows out of the CDQ furnace; Waste heat recovery: the mixed circulating gas enters the first dust collector through the dry quenching furnace outlet for further combustion, and the first dust collector maintains the first preset temperature before entering the waste heat boiler; Waste heat circulation: After the waste heat boiler reduces the temperature of the mixed circulating gas to a second preset temperature, the mixed circulating gas is dedusted by the second dust collector and then enters the feed water preheater for heat exchange to form the circulating bypass gas. After the heat exchange, the bypass circulating gas enters the cooling section of the dry quenching furnace through the second circulating bypass pipeline to cool the coke, and enters the premixer through the first circulating bypass pipeline to wait for mixing with the external coal gas, and continues to circulate according to the above steps.

8. The method for introducing coal gas into a dry coke quenching system according to claim 7, characterized in that: In the step of circulating premixing, the external coal gas is introduced when the temperature of the circulating gas at the outlet of the first dust collector is ≥700°C.

9. The method for introducing coal gas into a dry coke quenching system according to claim 7, characterized in that: In the waste heat circulation step, the circulating bypass gas is sampled online during the process of entering the cooling section of the dry quenching furnace through the second circulating bypass pipeline. The circulating bypass gas is sampled and analyzed. When the volume fraction of the combustible component CO is greater than 6% and the volume fraction of H2 is greater than 3% in the analysis data, the introduction of the coal gas is stopped.

10. The method for introducing coal gas into a dry quenching system according to claim 7, characterized in that: The first preset temperature is set to 900°C to 980°C, and the second preset temperature is set to 160°C to 180°C.

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