Method for quickly starting coke oven chimney

Abstract

The invention belongs to the field of coal coking, and particularly relates to a method for quickly starting a coke oven chimney, which is characterized by comprising an injection gas source, a pressure release valve, an injection unit and a connecting gas circuit, and the injection gas source is a container with certain volume for storing high-pressure gas or a facility capable of providing a stable gas source; the injection gas source is connected with the injection units through the connecting gas path, and the injection units are uniformly arranged at the root of the coke oven chimney in the circumferential direction. And the pressure release valve is a normally closed valve and is opened in linkage with the coke oven flue main flashboard, or is independently opened after receiving an emergency opening instruction. The method has the advantages that coke oven chimney equipment does not need to be considered, extra energy consumption is not needed, the flue gas waste heat of the coke oven can be fully recovered, and extreme energy efficiency utilization in the production process of the coke oven is realized; the normal production of the coke oven can be ensured without consuming fuel to maintain the normal operation of the desulfurization and denitrification system of the coke oven, so that the operation cost can be obviously reduced; and continuous supply of high-pressure gas is not needed, and almost zero-cost operation is achieved.

Description

Technical Field

[0001] The invention belongs to the field of coal coking, and in particular relates to a method for realizing rapid activation of a coke oven chimney. Background Art

[0002] Coke oven flue gas is the waste gas produced by the combustion of fuel to provide the required heat energy for the coke oven during the coking process. The coke oven flue gas contains a certain amount of NOx, SO 2 Air pollutants and greenhouse gases such as CO 2 , while carrying waste heat accounting for about 17% of the total heat output of the coke oven. With the increasingly stringent environmental laws and regulations and the need for green development, the NOx and SO in the coke oven flue gas are being 2 The control of atmospheric pollutants such as CO2 has become an important and indispensable part of coking production, and the full and effective recovery of waste heat carried by coke oven flue gas is also an inevitable requirement for achieving ultimate energy-efficient coking.

[0003] In the existing coke oven flue gas desulfurization and denitrification technology, the coke oven flue gas with a temperature of 180℃ to 300℃ is sent into the coke oven chimney by the desulfurization and denitrification system fan for discharge after desulfurization and denitrification. The pressure required for the normal production of the coke oven heating system is provided by the desulfurization and denitrification system fan. In order to ensure the normal production of the coke oven when the coke oven flue gas desulfurization and denitrification system fails suddenly, it is required to take hot standby measures for the coke oven chimney to maintain the temperature of the gas flowing in the coke oven chimney at 100℃ to 130℃ or higher. To this end, certain technical measures are usually taken to allow the gas with a temperature of 100℃ to 130℃ or higher to be continuously discharged through the coke oven chimney, keeping the chimney in a hot standby state. Such as:

[0004] The Chinese patents "CN201520394546 A coke oven flue gas hot standby system" and "CN202320079753 A low-temperature coke oven flue gas desulfurization, denitrification and waste heat utilization system" propose using a heat exchanger to exchange heat between air and the coke oven flue gas after denitrification and waste heat boiler, and the air is heated and sent into the coke oven chimney, thereby solving the chimney's hot standby problem.

[0005] The Chinese patent "CN201610295380 Desulfurization and Denitrification Method and Device for Hot Standby Coke Oven Chimney Using Coke Oven Flue Gas" proposes to utilize the 160℃~180℃ coke oven flue gas discharged from the waste heat boiler to heat the 60℃~80℃ coke oven flue gas discharged from the desulfurization and denitrification absorption tower to 120℃~130℃ in the hot standby heat exchanger and then send it into the coke oven chimney to solve the hot standby problem of the chimney.

[0006] The Chinese patent "CN201620479180 A coke oven chimney hot standby system suitable for flue gas wet desulfurization and denitrification process" proposes to use a gas-to-gas heat exchanger to heat the clean coke oven flue gas after desulfurization and denitrification using the sensible heat of the high-temperature coke oven flue gas before desulfurization and denitrification, and then send the heated clean coke oven flue gas into the coke oven chimney to achieve hot standby of the coke oven chimney.

[0007] The Chinese patent "CN201620753101 A system for low-temperature denitration, wet desulfurization and dust removal and ensuring hot standby of chimney" proposes to use the sensible heat of the coke oven flue gas after denitration to heat a certain amount of air through an air heat exchanger, and then send the heated air into the coke oven chimney for hot standby of the coke oven chimney.

[0008] The Chinese patent "CN201621451587 A device for hot standby of coke oven chimney" proposes to heat a certain amount of air through an air heat exchanger using the sensible heat of the high-temperature coke oven flue gas before desulfurization, and then send the heated air into the coke oven chimney for hot standby of the coke oven chimney.

[0009] The Chinese patent "CN201820466613 Unpowered Hot Standby System for Coke Oven Chimney" proposes opening an air inlet at the root of the coke oven chimney, using steam to heat the air entering the coke oven chimney from the root of the coke oven chimney, and discharging the heated air through the coke oven chimney, so that the coke oven chimney is always in a hot standby state.

[0010] The above-mentioned technical measures, whether heating the flue gas after desulfurization and denitrification to 100℃~130℃ or higher, or heating the air to 100℃~130℃ or higher, require the installation of necessary heat exchange equipment, and at the same time, a large amount of heat needs to be exchanged from the coke oven flue gas or additionally provided to achieve this. The flue gas or air discharged from the coke oven chimney carries a large amount of waste heat and is discharged, resulting in insufficient recovery and utilization of energy.

[0011] The Chinese patent "CN201621151226 A desulfurization and denitrification energy-saving integrated purification system for coke oven flue gas" proposes to set a coaxial internal combustion engine for the coke oven flue gas induced draft fan. When encountering an emergency power outage or a fault trip, the coaxial internal combustion engine is used to replace the induced draft fan drive motor to ensure the normal operation of the desulfurization and denitrification system, while also avoiding the drop in flue pressure caused by the power outage. This method can cancel the long-term hot standby of the coke oven chimney, but when encountering an emergency power outage or a fault trip, in order to avoid the drop in flue pressure caused by the power outage, it is necessary to start the internal combustion engine, and the internal combustion engine continuously consumes fuel to ensure the normal production of the coke oven. While increasing the investment in the construction of the coke oven flue gas purification system, this solution also increases new energy consumption and pollutant emissions. Summary of the invention

[0012] The purpose of the present invention is to provide a method for quickly activating a coke oven chimney, overcome the shortcomings of the prior art, and realize the rapid recovery of the coke oven chimney to a normal production state without continuously consuming energy for hot standby of the coke oven chimney.

[0013] To achieve the above object, the present invention is implemented through the following technical solutions:

[0014] A method for realizing rapid activation of a coke oven chimney, wherein a smoke ejection device is arranged in the coke oven chimney, the smoke ejection device comprising an ejection gas source, a pressure relief valve, an ejection unit and a connecting gas path, the ejection gas source being connected to the ejection unit through the connecting gas path; when it is necessary to restore the pressure required for normal production in the coke oven chimney, the smoke ejection device is quickly opened, forming a power from the root upward in the coke oven chimney, guiding the hot smoke from the coke oven flue to be continuously discharged upward through the chimney, thereby forming a pressure difference required for normal production of the coke oven inside and outside the chimney, ensuring rapid restoration of the normal production state of the coke oven chimney, and realizing normal, safe and stable production of the coke oven, and the specific operation steps are as follows:

[0015] S1) opening the damper of the main flue of the coke oven and opening the pressure relief valve arranged on the gas path connecting the induced gas source and the injection unit;

[0016] S2) The high-pressure gas in the induced gas source enters the injection unit inside the coke oven chimney along the connecting gas path, and is ejected from the injection unit at a high speed;

[0017] S3) The high-speed airflow ejected has an ejection effect in the vicinity thereof and generates an ejection airflow, which drives the cold air in the coke oven chimney upward to the top outlet of the coke oven chimney;

[0018] S4) As the gate of the coke oven main flue opens at the root of the coke oven chimney, the high-temperature coke oven flue gas from the coke oven flue quickly flows from the root of the coke oven chimney to the top outlet of the coke oven under the induced effect of the injection unit and the thermal buoyancy of the flue gas itself;

[0019] S5) The flow of high-temperature coke oven flue gas in the coke oven chimney generates a pressure difference between the inside and outside of the coke oven chimney, and the generated pressure difference causes a stable flow of high-temperature coke oven flue gas to be formed in the coke oven chimney, thereby realizing the normal and stable operation of the coke oven heating system and avoiding the impact on the coke oven production;

[0020] S6) After the coke oven chimney relies on the coke oven flue gas's own power to meet the normal and stable operation requirements of the heating system, close the pressure relief valve.

[0021] Furthermore, the induced gas source is a container with a certain volume for storing high-pressure gas or a facility that can provide a stable gas source, and the pressure is always maintained above a certain initial pressure during the closing of the pressure relief valve.

[0022] Furthermore, the pressure relief valve is a normally closed valve, which is opened in conjunction with the main damper of the coke oven flue, or is opened independently after receiving an emergency opening command.

[0023] Furthermore, the outlet direction of the injection port of the injection unit is in the same direction as the outlet from the root of the coke oven chimney to the top of the coke oven chimney, and the angle between the center line of the injection port outlet and the center line of the coke oven chimney is between 10° and 80°.

[0024] Furthermore, the injection units are arranged in layers at different heights of the coke oven chimney, and the injection ports of each layer are connected to the induced air source through a connecting air path; and a plurality of the injection units are evenly arranged around the circumference of the coke oven chimney.

[0025] Furthermore, normally closed valves are respectively arranged on the connecting air paths of the layered injection units. After the normally closed valves on the connecting air paths of the pressure relief valve and the highest injection unit are synchronously opened, the injection units from the highest injection unit downward are opened with a delayed sequence, and an upward induced airflow is formed from top to bottom in the coke oven chimney, thereby quickly induced and discharged the high-temperature coke oven flue gas from the main gate of the coke oven flue at the lower part of the coke oven chimney.

[0026] Furthermore, an airflow ejection structure is provided inside the coke oven chimney, and the airflow ejection structure is a Venturi structure.

[0027] Furthermore, the initial pressure of the induced gas source is not less than 0.2 MPa.

[0028] Furthermore, the initial pressure of the induced gas source is above 0.6 MPa.

[0029] Furthermore, the gas storage capacity of the induced gas source should ensure that the pressure in the container is greater than 0.1 MPa 10 seconds after the pressure relief valve is opened.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] 1) Low construction cost. When the flue gas desulfurization and denitrification system of the coke oven fails or the system is shut down due to an emergency power outage, the flue gas ejection device forms an external discharge force in the coke oven chimney, guides the high-temperature coke oven flue gas from the gate plate of the coke oven main flue to be quickly discharged through the coke oven chimney, so that the coke oven chimney in a cold state quickly recovers to a state that ensures the normal production of the coke oven; the present invention does not require the installation of heat exchange equipment, and also does not require the consumption of fuel to maintain the normal operation of the coke oven desulfurization and denitrification system to ensure the normal production of the coke oven, thereby avoiding the increase in the construction cost of the coke oven flue gas desulfurization and denitrification system;

[0032] 2) Simple maintenance and reliable operation. The present invention only requires the existence of a high-pressure gas storage facility with a certain pressure and volume, and does not consume any energy at ordinary times. The system maintenance is simple and convenient. When in use, it only consumes limited high-pressure gas in the high-pressure gas storage facility, and does not require continuous supply of high-pressure gas, and operates at almost "zero" cost;

[0033] 3) The present invention does not need to use hot flue gas or hot air with sufficient temperature to be discharged through the coke oven chimney for a long time to maintain the hot standby state of the chimney. The temperature of the coke oven flue gas discharged through the coke oven chimney can be reduced to below 100°C or lower, reducing the heat loss carried by the flue gas, and realizing the ultimate recovery and utilization of the waste heat energy of the coke oven flue gas. At the same time, there is no need to supplement additional energy to meet the hot standby needs of the coke oven chimney, thereby further achieving energy saving and consumption reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a schematic diagram of the process flow of Embodiment 1 of the present invention;

[0035] Figure 2 This is a schematic diagram of the connection between the coke oven chimney and the smoke ejection device in the second embodiment of the present invention;

[0036] Figure 3 yes Figure 2 Sectional view along line AA;

[0037] Figure 4 yes Figure 2 Sectional view along line BB;

[0038] Figure 5 It is a schematic diagram of the airflow injection structure in the third embodiment of the present invention.

[0039] In the figure: 1-injection gas source, 2-pressure relief valve, 3-connecting gas line, 4-injection unit, 5-coke oven flue main gate, 6-coke oven, 7-desulfurization and denitrification system, 8-waste heat recovery system, 9-normally closed valve, 10-injection port, 11-coke oven chimney, 12-airflow injection structure. DETAILED DESCRIPTION

[0040] The technical solution of the present invention will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0041] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the specific embodiments required to be used in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the specific embodiments described below are some implementation methods of the present invention. For ordinary technicians in this field, other specific embodiments can be obtained based on these specific embodiments without paying creative work.

[0042] The components of the embodiments of the present invention generally described and shown in the specific embodiments herein can be arranged and designed in countless different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the specific embodiments is not intended to limit the scope of the invention claimed, but merely represents selected embodiments of the present invention.

[0043] See Figure 1 , is a schematic diagram of the process flow of the first embodiment of the present invention. During normal production, the pressure required by the coke oven heating system is provided by the induced draft fan of the coke oven flue gas desulfurization and denitrification system 7. The coke oven flue gas is passed through the coke oven flue gas desulfurization and denitrification system 7 and the coke oven flue gas waste heat recovery system 8 to achieve pollutant emission reduction and waste heat energy recovery. The flue gas that has undergone desulfurization, denitrification and waste heat recovery is then discharged through the coke oven chimney 11. When the coke oven flue gas desulfurization and denitrification system 7 fails or an emergency power outage causes the system to shut down, the power generated by the flue gas ejection device arranged in the coke oven chimney 11 guides the high-temperature coke oven flue gas from the main gate plate 5 of the coke oven flue to be quickly discharged through the coke oven chimney 11, so that the coke oven chimney 11 in a cold state quickly recovers to a state that ensures the normal production of the coke oven 6.

[0044] The flue gas induced gas device includes an induced gas source 1, a pressure relief valve 2, a connecting gas line 3, and an injection unit 4. The induced gas source 1 is a container with a certain volume for storing high-pressure gas or a facility that can provide a stable gas source. The induced gas source 1 is connected to the injection unit 4 through the connecting gas line 2. The pressure relief valve 2 is a normally closed valve, which is opened in conjunction with the main gate plate 5 of the coke oven flue, or is opened separately after receiving an emergency opening command. The outlet direction of the injection port of the injection unit 4 is in the same direction as the outlet from the root of the coke oven chimney to the top of the coke oven chimney, and the angle a between the center line of the outlet of the injection port 10 and the center line of the coke oven chimney is between 10° and 80°. The initial pressure in the induced gas source 1 is not less than 0.2MPa. The preferred value is above 0.6MPa. The gas storage capacity of the induced gas source 1 should ensure that the pressure in the container is greater than 0.1MPa after the pressure relief valve is opened for 10s.

[0045] See Figure 2-4 , is a schematic diagram of the connection between the coke oven chimney and the flue gas induced emission device in the second embodiment of the present invention, the injection unit 4 is arranged in layers at different heights of the coke oven chimney 11, and the injection ports of each layer are connected to the induced emission gas source 1 through the connecting gas path 3, and multiple injection units 4 are evenly arranged around the circumference of the coke oven chimney. Normally closed valves 9 are respectively arranged on the connecting gas paths of the layered injection units, and after the pressure relief valve 2 and the normally closed valves on the connecting gas paths of the highest layer injection unit are synchronously opened, the injection units of each section from the highest layer injection unit downward are delayed to open in sequence, and an upward induced emission gas flow is continuously formed from top to bottom in the coke oven chimney, so that the high-temperature coke oven flue gas from the main gate of the coke oven flue at the lower part of the coke oven chimney is quickly induced and discharged.

[0046] See Figure 5, is a schematic diagram of the airflow ejection structure in the third embodiment of the present invention. On the basis of the first and second embodiments, in order to make the flue gas ejection device play a better role, an airflow ejection structure 12 is provided inside the coke oven chimney 11. The airflow ejection structure is of a Venturi type. When the high-pressure gas ejected from the ejection unit 4 passes through the airflow ejection structure 12 arranged above it, it further produces an ejection effect around it, and the cold gas in the coke oven chimney 11 is quickly and efficiently guided to the outlet of the coke oven chimney 11, thereby quickly restoring the normal flow of the high-temperature coke oven flue gas in the coke oven chimney 11.

[0047] The present invention provides a method for realizing rapid activation of a coke oven chimney, which is to arrange a flue gas ejection device in the coke oven chimney. When it is necessary to restore the pressure required for normal production in the coke oven chimney, the flue gas ejection device is quickly opened to form a power from the root upward in the coke oven chimney, and to guide the hot flue gas from the coke oven flue to be continuously discharged upward through the chimney, thereby forming a pressure difference required for normal production of the coke oven inside and outside the chimney, and rapidly restoring the normal production state of the coke oven chimney. The temperature of the coke oven flue gas discharged through the coke oven chimney 11 does not need to consider the hot standby need of the coke oven chimney 11, so that the coke oven flue gas waste heat recovery system 8 can recover the waste heat energy of the coke oven flue gas to the extreme. The specific operation steps are as follows:

[0048] S1) When the coke oven flue gas desulfurization and denitrification system 7 fails or the system is shut down due to an emergency power outage, the pressure required by the coke oven heating system can no longer be provided by the induced draft fan of the coke oven flue gas desulfurization and denitrification system 7. At this time, the damper of the coke oven main flue is opened, and the pressure relief valve arranged on the gas path connecting the induced air source and the injection unit is opened;

[0049] S2) After the pressure relief valve 2 is opened, the high-pressure gas in the induced gas source enters the injection unit inside the coke oven chimney along the connecting gas path and is ejected from the injection unit at a high speed; the induced gas source is always kept above a certain initial pressure;

[0050] S3) After the pressure relief valve 2 is opened, the high-pressure gas in the induced gas source 1 enters the injection unit 4 inside the coke oven chimney 11 along the connecting gas path 3 under the action of pressure, and an induced effect occurs near the high-speed ejected airflow and an induced airflow is generated, and the induced airflow drives the cold air in the coke oven chimney to flow upward to the top outlet of the coke oven chimney;

[0051] S4) At the root of the coke oven chimney, as the gate of the coke oven main flue is opened, the high-temperature coke oven flue gas from the coke oven flue flows rapidly from the root of the coke oven chimney to the top outlet of the coke oven under the induced effect of the injection unit and the thermal buoyancy of the flue gas itself;

[0052] S5) The flow of high-temperature coke oven flue gas in the coke oven chimney generates a pressure difference inside and outside the coke oven chimney, and the generated pressure difference causes a stable flow of high-temperature coke oven flue gas to be formed in the coke oven chimney, thereby realizing the normal and stable operation of the coke oven heating system and avoiding the impact on the coke oven production;

[0053] S6) After the coke oven chimney relies on the power of the coke oven flue gas to meet the normal and stable operation requirements of the heating system, the pressure relief valve 2 is closed and the operation is completed.

[0054] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for realizing rapid activation of a coke oven chimney, characterized in that: A flue gas ejection device is arranged in the coke oven chimney, and the flue gas ejection device comprises an ejection gas source, a pressure relief valve, an ejection unit and a connecting gas path, and the ejection gas source is connected to the ejection unit through the connecting gas path; when it is necessary to restore the pressure required for normal production in the coke oven chimney, the flue gas ejection device is quickly opened to form a power from the root upward in the coke oven chimney, and guide the hot flue gas from the coke oven flue to be continuously discharged upward through the chimney, thereby forming a pressure difference required for normal production of the coke oven inside and outside the chimney, ensuring that the normal production state of the coke oven chimney is quickly restored, and realizing normal, safe and stable production of the coke oven. The specific operation steps are as follows: S1) opening the damper of the main flue of the coke oven and opening the pressure relief valve arranged on the gas path connecting the induced gas source and the injection unit; S2) The high-pressure gas in the induced gas source enters the injection unit inside the coke oven chimney along the connecting gas path, and is ejected from the injection unit at a high speed; S3) The high-speed airflow ejected has an ejection effect in the vicinity thereof and generates an ejection airflow, which drives the cold air in the coke oven chimney upward to the top outlet of the coke oven chimney; S4) As the gate of the coke oven main flue opens at the root of the coke oven chimney, the high-temperature coke oven flue gas from the coke oven flue quickly flows from the root of the coke oven chimney to the top outlet of the coke oven under the induced effect of the injection unit and the thermal buoyancy of the flue gas itself; S5) The flow of high-temperature coke oven flue gas in the coke oven chimney generates a pressure difference between the inside and outside of the coke oven chimney, and the generated pressure difference causes a stable flow of high-temperature coke oven flue gas to be formed in the coke oven chimney, thereby realizing the normal and stable operation of the coke oven heating system and avoiding the impact on the coke oven production; S6) After the coke oven chimney relies on the coke oven flue gas's own power to meet the normal and stable operation requirements of the heating system, close the pressure relief valve.

2. A method for realizing rapid activation of a coke oven chimney according to claim 1, characterized in that: The induced gas source is a container with a certain volume for storing high-pressure gas or a facility that can provide a stable gas source, and the initial pressure is always maintained above a certain level during the closing of the pressure relief valve.

3. A method for realizing rapid activation of a coke oven chimney according to claim 1, characterized in that: The pressure relief valve is a normally closed valve, which is opened in conjunction with the main damper of the coke oven flue, or is opened independently after receiving an emergency opening command.

4. A method for realizing rapid activation of a coke oven chimney according to claim 1, characterized in that: The outlet direction of the injection port of the injection unit is in the same direction as the outlet from the root of the coke oven chimney to the top of the coke oven chimney, and the angle between the center line of the injection port outlet and the center line of the coke oven chimney is between 10° and 80°.

5. The method for realizing rapid activation of a coke oven chimney according to claim 1, characterized in that: The injection units are arranged in layers at different heights of the coke oven chimney, and the injection ports of each layer are connected with the induced air source through a connecting air path; a plurality of the injection units are evenly arranged around the circumference of the coke oven chimney.

6. A method for realizing rapid activation of a coke oven chimney according to claim 5, characterized in that: Normally closed valves are respectively arranged on the connecting air paths of the layered injection units. After the normally closed valves on the connecting air paths of the pressure relief valve and the highest injection unit are synchronously opened, the injection units from the highest injection unit downward are opened in sequence with a delayed opening, and an upward induced airflow is formed from top to bottom in the coke oven chimney, thereby quickly induced and discharged the high-temperature coke oven flue gas from the main gate of the coke oven flue at the lower part of the coke oven chimney.

7. A method for realizing rapid activation of a coke oven chimney according to claim 1, characterized in that: An airflow ejection structure is arranged inside the coke oven chimney, and the airflow ejection structure is a Venturi structure.

8. A method for realizing rapid activation of a coke oven chimney according to claim 2, characterized in that: The initial pressure of the induced gas source is not less than 0.2 MPa.

9. A method for realizing rapid activation of a coke oven chimney according to claim 8, characterized in that: The initial pressure of the induced gas source is above 0.6 MPa.

10. A method for realizing rapid activation of a coke oven chimney according to claim 2, characterized in that: The gas storage capacity of the induced gas source should ensure that the pressure in the container is greater than 0.1 MPa 10 seconds after the pressure relief valve is opened.

Images