A gas boiler system convenient for cleaning tar and its online coke cleaning method

Abstract

The present invention provides a gas boiler system that is convenient for cleaning tar, including a boiler, at least two burners, a coke oven gas intake main pipe, a blast furnace gas intake main pipe, and a purge intake pipe, wherein the burners are all installed on the boiler; the coke oven gas intake main pipe is connected to at least two coke oven gas intake branches, the blast furnace gas intake main pipe is connected to at least two blast furnace gas intake branches, the coke oven gas intake branches and the blast furnace gas intake branches are respectively connected one-to-one with the burner; the purge intake pipe is connected one-to-one with the coke oven gas intake branches. An online coke cleaning method based on the above-mentioned gas boiler system. The system and method of the present invention use purge gas to purge the branch pipe separately, without stopping other burners, and can ensure the normal operation of the boiler. In addition, the burner remains connected to the boiler, and the furnace temperature of the boiler can be used to soften the tar in the burner and keep it in a softened state, which is convenient for cleaning the tar.

Description

Technical Field

[0001] The invention relates to the technical field of gas boilers, and in particular to a gas boiler system which is convenient for cleaning tar and an online tar cleaning method thereof. Background Art

[0002] Gas boilers are generally heat energy conversion devices that use combustible gas as fuel. The heat released by burning in the furnace heats the water in the boiler and vaporizes it into steam. For large-capacity gas boilers, it should be noted that at least two burners must be arranged, and they should be arranged from top to bottom. When the load is reduced or the burner is overhauled, the burners can be used alternately without affecting the normal operation of the gas boiler.

[0003] In the steel industry, gas boilers use recycled blast furnace gas as fuel. However, blast furnace gas has a low calorific value and is not easy to ignite. Therefore, it is necessary to first ignite it with coke oven gas or natural gas with a higher calorific value, and then add blast furnace gas to ignite it after the combustion is stable. At the same time, during operation, a certain amount of coke oven gas will be added to participate in the combustion according to the boiler operating conditions to play a gas regulation role. Although coke oven gas is a high calorific value raw gas, it contains more tar and naphthalene. In the long-term operation process, these tars and naphthalene will accumulate and block the pipelines and burners, affecting the boiler's fire adjustment work, so the accumulated tar in the burner needs to be cleaned regularly.

[0004] In the prior art, the cleaning of the burner generally adopts an offline solution or an online solution. The offline solution refers to the burner being removed from the gas boiler for cleaning, and the online solution refers to the burner being kept installed on the gas boiler for cleaning. However, in order to ensure safety, whether it is an offline solution or an online solution, it is necessary to purge and clean the coke oven gas in the burner and its pipeline. In this case, it is necessary to introduce purge gas from the main pipe before the pipeline and the burner are separated, and the multiple burners connected to the main pipe must stop running, which will cause the operation of the entire gas boiler to stop, increasing the cleaning cost of the burner. In addition, if the offline solution is adopted, the disassembled burner cools down quickly, causing the tar to harden rapidly at room temperature and firmly adhere to the inner wall of the coke gas channel of the burner, which makes it very difficult to clean and does not achieve the expected effect. Summary of the invention

[0005] 1. Technical Problems Solved

[0006] In view of the deficiencies in the prior art, the present invention provides a gas boiler system and an online de-coking method for tar that are convenient for cleaning, which solves the problem of cleaning the burner during boiler shutdown and the difficulty in handling the hardened tar in the burner.

[0007] 2. Technical Solution

[0008] To achieve the above object, the present invention provides the following technical solutions:

[0009] A gas boiler system is provided which is convenient for cleaning tar, and the key points of the system are as follows:

[0010] boiler;

[0011] at least two burners, both of which are mounted on the boiler;

[0012] A coke oven gas inlet main pipe, used for conveying coke oven gas, the coke oven gas inlet main pipe is connected to at least two coke oven gas inlet branch pipes, and the coke oven gas inlet branch pipes are connected one-to-one with the burner;

[0013] A blast furnace gas intake main pipe, used for conveying blast furnace gas, the blast furnace gas intake main pipe is connected to at least two blast furnace gas intake branches, and the blast furnace gas intake branches are connected one-to-one with the burner;

[0014] The purge air inlet pipe is connected one-to-one with the coke oven gas inlet branch pipe and is used to introduce purge gas into the coke oven gas inlet branch pipe when in use.

[0015] Optionally, the coke oven gas intake branch pipe includes a control section and a detachable disassembly section, the control section is connected to the coke oven gas intake main pipe, the two ends of the detachable section are respectively connected to the control section and the burner in a detachable manner, and the control section is sequentially provided with a regulating valve, a quick-cut valve and the purge intake pipe along the intake direction.

[0016] Optionally, the disassembly section of the coke oven gas inlet branch pipe is a hose.

[0017] Optionally, the purge air inlet pipe is connected one-to-one to the blast furnace gas inlet branch pipe.

[0018] Optionally, a control valve is provided on the purge air inlet pipe.

[0019] An online decoking method for a gas boiler system as described in any of the above examples is also provided, the key of which is to proceed according to the following steps:

[0020] S1. Determine the burner to be cleaned, keep the burner to be cleaned connected to the boiler, cut off the connection between the corresponding blast furnace gas intake branch pipe and the blast furnace gas intake main pipe, cut off the connection between the corresponding coke oven gas intake branch pipe and the coke oven gas intake main pipe, and the burner to be cleaned exits the operating state;

[0021] S2, the corresponding blast furnace gas intake branch pipe and coke oven gas intake branch pipe are introduced with purge gas to replace the coke oven gas and blast furnace gas in the blast furnace gas intake branch pipe, the coke oven gas intake branch pipe and the burner;

[0022] S3, the replacement of coke oven gas and blast furnace gas is complete, the introduction of purge gas is stopped, the coke oven gas inlet branch pipe is removed from the burner, and then the ignition device on the burner is removed to maintain the normal operation of the boiler, and the burner is cleaned of tar;

[0023] S4. After the tar cleaning is completed, the ignition device and the coke oven gas inlet branch pipe are reinstalled in order;

[0024] S5, introducing purge gas from the blast furnace gas inlet branch pipe and the coke oven gas inlet branch pipe to replace the air in the blast furnace gas inlet branch pipe, the coke oven gas inlet branch pipe and the burner;

[0025] S6. Connect the blast furnace gas inlet branch pipe to the blast furnace gas inlet main pipe, and connect the coke oven gas inlet branch pipe to the coke oven gas inlet main pipe to restore the operation of the burner.

[0026] Optionally, the burner is operated to further increase the temperature and soften the tar before cleaning the tar.

[0027] Optionally, the pressure of the purge gas introduced into the coke oven gas inlet branch pipe is maintained at 0.5-1 MPa, and the purge gas replacement time is greater than 15 minutes.

[0028] Optionally, during the tar cleaning operation, the working pressure of the boiler furnace is maintained at -150 to -200 Pa.

[0029] Optionally, during the period when the purge gas replaces the air in step S5, a leak detection liquid is applied to the disassembled connection parts and leaks are detected, and the next step is performed after confirming that there are no leaks.

[0030] 3. Beneficial Effects

[0031] 1. In the gas boiler system, the main coke oven gas inlet pipe is divided into multiple branch pipes, the burners are connected one-to-one through the branch pipes, and the purge inlet pipes are connected one-to-one on the branch pipes. The burners that need to be cleaned can be purged separately to keep the normal operation of other burners, thereby ensuring the normal operation of the boiler and cleaning the burner without stopping the boiler. Therefore, when cleaning the burner, the burner does not need to be removed from the boiler. When cleaning the tar, the boiler temperature can be used to soften the tar in the burner and keep it in a softened state. Therefore, this gas boiler system lays the foundation for online cleaning of the burner.

[0032] 2. In the online decoking method, the branch pipe is purged separately with the purge gas, and other burners do not need to be shut down, thus ensuring the normal operation of the boiler. In addition, the burner remains connected to the boiler, and the furnace temperature of the boiler can be used to soften the tar in the burner and keep it in a softened state, which is convenient for cleaning the tar. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a structural schematic diagram of the gas boiler system of the present invention;

[0034] Among them, 1-boiler; 2-burner; 3-coke oven gas inlet main pipe; 4-blast furnace gas inlet main pipe; 5-purge inlet pipe; 6-coke oven gas inlet branch pipe; 6a-control section; 6b-disassembly and assembly section; 7-blast furnace gas inlet branch pipe; 8-control valve; 9-regulating valve; 10-quick-cut valve. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] Example

[0037] Figure 1 The present invention is a schematic structural diagram of a gas boiler system that is convenient for cleaning tar.

[0038] like Figure 1 As shown, a gas boiler system convenient for cleaning tar comprises a boiler 1, at least two burners 2, a coke oven gas intake main pipe 3 for conveying coke oven gas, a blast furnace gas intake main pipe 4 for conveying blast furnace gas, and a purge intake pipe 5 for introducing purge gas.

[0039] In detail, the burners 2 are all installed on the boiler 1; the coke oven gas inlet main pipe 3 is connected to at least two coke oven gas inlet branch pipes 6, and the coke oven gas inlet branch pipes 6 are connected one-to-one with the burners 2; the blast furnace gas inlet main pipe 4 is connected to at least two blast furnace gas inlet branch pipes 7, and the blast furnace gas inlet branch pipes 7 are connected one-to-one with the burners 2; the purge inlet pipe 5 is connected one-to-one with the coke oven gas inlet branch pipes 6 and the blast furnace gas inlet branch pipes 7, and when in use, it is used to introduce purge gas into the coke oven gas inlet branch pipes 6, and a control valve 8 is provided on the purge inlet pipe 5.

[0040] In detail, the coke oven gas intake branch pipe 6 includes a control section 6a and a detachable disassembly section 6b. The control section 6a is connected to the coke oven gas intake main pipe 3. The two ends of the detachable section 6b are respectively connected to the control section 6a and the burner 2 by flanges. The flange connection has good sealing performance and is easy to disassemble. The control section 6a is sequentially provided with a regulating valve 9, a quick-cut valve 10 and the purge intake pipe 5 along the intake direction. The intake amount of the coke oven gas can be controlled by the regulating valve 9, and the quick-cut valve 10 can quickly cut off the connection between the coke oven gas intake branch pipe 6 and the coke oven gas intake main pipe 3 to prevent leakage of the coke oven gas.

[0041] In detail, the disassembly section 6b of the coke oven gas inlet branch pipe 6 adopts a metal braided hose. Due to the limited space in the equipment area, the metal braided hose can be moved to make room for easy disassembly of the pipeline.

[0042] Working principle: A purge inlet pipe 5 is added to the coke oven gas inlet branch pipe 6 and the blast furnace gas inlet branch pipe 7, which is used to replace the coke oven gas and blast furnace gas in each inlet branch pipe and the burner 2 to be cleaned before decoking, and at the same time, the ash in the burner 2 can be purged. The purge gas generally uses nitrogen, so that other normally operating burners 2 do not need to stop running, and the boiler 1 can also maintain normal operation. At the same time, the burner 2 does not need to be disassembled from the boiler 1. The furnace temperature of the normally operating boiler 1 can be used to soften the tar in the burner 2 and keep the tar in a softened state, so that after the disassembly section 6b of the coke oven gas inlet branch pipe 6 is removed, the tar in the burner 2 can be quickly cleaned.

[0043] based on Figure 1 The gas boiler system shown is convenient for cleaning tar, and also provides an online decoking method. The specific steps are as follows:

[0044] S1. Observe the yellow flame in the furnace through the flame probe, and judge the blockage of the coking coal channel of burner 2 based on the coking coal branch pipe flow. If it is found that the yellow flame is small and the coking coal flow is significantly reduced, it can be determined that burner 2 needs to be cleaned.

[0045] Keep the burner 2 to be cleaned connected to the boiler 1, cut off the connection between the corresponding blast furnace gas intake branch pipe 7 and the blast furnace gas intake main pipe 4, cut off the connection between the corresponding coke oven gas intake branch pipe 6 and the coke oven gas intake main pipe 3, and the burner 2 to be cleaned exits the operating state.

[0046] S2. Purge gas is introduced into the corresponding blast furnace gas inlet branch pipe 7 and coke oven gas inlet branch pipe 6. The pressure of the purge gas is maintained at 0.5-1Mpa to replace the coke oven gas and blast furnace gas in the blast furnace gas inlet branch pipe 7, the coke oven gas inlet branch pipe 6 and the burner 2. The replacement time is greater than 15 minutes.

[0047] S3, the replacement of coke oven gas and blast furnace gas is complete, the introduction of purge gas is stopped, the disassembly section 6b of the coke oven gas inlet branch pipe 6 is removed from the burner 2, and the gas concentration is tested on site by a gas alarm. In addition, in order to further prevent gas leakage, a hard blind plate can be installed at the flange of the control section 6a after the disassembly section 6b is removed. Next, the ignition device on the burner 2 is removed, the normal operation of the boiler 1 is maintained, and the burner 2 is cleaned of tar.

[0048] S4. After the tar cleaning is completed, the ignition device and the coke oven gas inlet branch pipe 6 are reinstalled in order.

[0049] S5. Purge gas is introduced from the blast furnace gas inlet branch pipe 7 and the coke oven gas inlet branch pipe 6. The pressure of the purge gas is maintained at 0.5-1Mpa to replace the air in the blast furnace gas inlet branch pipe 7, the coke oven gas inlet branch pipe 6 and the burner 2. The replacement time is greater than 15 minutes. During the period when the purge gas replaces the air, the disassembled connection parts are coated with leak detection liquid and leaks are detected. After confirming that there are no leaks, proceed to the next step.

[0050] S6. Connect the blast furnace gas inlet branch pipe 7 to the blast furnace gas inlet main pipe 4, and connect the coke oven gas inlet branch pipe 6 to the coke oven gas inlet main pipe 3, and then the operation of the burner 2 can be restored.

[0051] It should be noted that, in order to further ensure that the tar in the burner 2 is completely softened, the burner 2 can be put into operation for 0.5 to 1 hour before cleaning to further heat up and soften the tar. In order to ensure that the purge gas can smoothly enter the corresponding air intake branch pipe, the pressure of the purge gas introduced into the coke oven gas intake branch pipe 6 and the blast furnace gas intake branch pipe 7 is maintained at 0.5 to 1Mpa. During the tar cleaning operation, the working pressure of the furnace of the boiler 1 is maintained at -150 to -200Pa, so that a negative pressure can be formed in the burner 2 and air can be inhaled to increase the oxygen content. In addition, the gas and heat flow in the boiler 1 are prevented from flowing back, achieving multiple goals at one stroke and ensuring the safety of the cleaning staff. At the same time, in order to ensure thorough replacement, the purge gas replacement time needs to be guaranteed to be more than 15 minutes.

[0052] Furthermore, through this method, when the coke oven gas passage of the burner 2 is blocked, the burner 2 can be cleaned online without stopping the boiler 1, and the boiler 1 does not stop, which indirectly improves the economic benefits of the boiler 1. At the same time, because the boiler 1 is in operation, the temperature of the boiler 1 can be used to maintain the softened state of the tar, which is easier to clean than the hardened tar at room temperature, and can achieve a better cleaning effect.

[0053] It should also be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[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 gas boiler system that is convenient for cleaning tar, characterized in that: include: boiler; at least two burners, both of which are mounted on the boiler; A coke oven gas inlet main pipe, used for conveying coke oven gas, the coke oven gas inlet main pipe is connected to at least two coke oven gas inlet branch pipes, and the coke oven gas inlet branch pipes are connected one-to-one with the burner; A blast furnace gas inlet main pipe, used for conveying blast furnace gas, the blast furnace gas inlet main pipe is connected to at least two blast furnace gas inlet branch pipes, and the blast furnace gas inlet branch pipes are connected one-to-one with the burner; a purge air inlet pipe, which is connected one-to-one with the coke oven gas inlet branch pipe and is used to introduce purge gas into the coke oven gas inlet branch pipe when in use; The coke oven gas intake branch pipe includes a control section and a detachable disassembly section. The control section is connected to the coke oven gas intake main pipe. The two ends of the detachable section are respectively detachably connected to the control section and the burner. The control section is sequentially provided with a regulating valve, a quick-cut valve and the purge intake pipe along the intake direction.

2. A gas boiler system for facilitating tar cleaning according to claim 1, characterized in that: The disassembly section of the coke oven gas inlet branch pipe is a hose.

3. A gas boiler system for facilitating tar cleaning according to claim 1 or 2, characterized in that: The blast furnace gas inlet branch pipe is connected one-to-one with the purge inlet pipe.

4. A gas boiler system for facilitating tar cleaning according to claim 3, characterized in that: The purge air inlet pipe is provided with a control valve.

5. An online decoking method for a gas boiler system according to any one of claims 1 to 4, characterized in that: Follow these steps: S1. Determine the burner to be cleaned, keep the burner to be cleaned connected to the boiler, cut off the connection between the corresponding blast furnace gas intake branch pipe and the blast furnace gas intake main pipe, cut off the connection between the corresponding coke oven gas intake branch pipe and the coke oven gas intake main pipe, and the burner to be cleaned exits the operating state; S2, the corresponding blast furnace gas intake branch pipe and coke oven gas intake branch pipe are introduced with purge gas to replace the coke oven gas and blast furnace gas in the blast furnace gas intake branch pipe, the coke oven gas intake branch pipe and the burner; S3, the replacement of coke oven gas and blast furnace gas is complete, the introduction of purge gas is stopped, the coke oven gas inlet branch pipe is removed from the burner, and then the ignition device on the burner is removed to maintain the normal operation of the boiler, and the burner is cleaned of tar; S4. After the tar cleaning is completed, the ignition device and the coke oven gas inlet branch pipe are reinstalled in order; S5, introducing purge gas from the blast furnace gas inlet branch pipe and the coke oven gas inlet branch pipe to replace the air in the blast furnace gas inlet branch pipe, the coke oven gas inlet branch pipe and the burner; S6. Connect the blast furnace gas inlet branch pipe to the blast furnace gas inlet main pipe, and connect the coke oven gas inlet branch pipe to the coke oven gas inlet main pipe to restore the operation of the burner.

6. The online defocusing method according to claim 5, characterized in that: The burner is operated to further increase the temperature and soften the tar before cleaning the tar.

7. The online defocusing method according to claim 5 or 6, characterized in that: The pressure of the purge gas introduced into the coke oven gas inlet branch pipe is maintained at 0.5-1 MPa, and the purge gas replacement time is greater than 15 minutes.

8. The online defocusing method according to claim 7, characterized in that: During the tar cleaning operation, the working pressure of the boiler furnace is maintained at -150 to -200 Pa.

9. The online defocusing method according to claim 5 or 6, characterized in that: During the period when the purge gas replaces the air in step S5, the disassembled connection parts are coated with leak detection liquid and leaks are detected. After confirming that there are no leaks, the next step is carried out.

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