A method for predicting tube explosion of a waste heat boiler in a dry quenching system
By setting up inert gas circulation pipelines and sensors in the dry quenching system, combined with a programmable controller, intelligent prediction of waste heat boiler tube rupture can be achieved, solving the problem of misjudgment caused by relying on human experience and improving system safety.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HEBEI UNIVERSITY
- Filing Date
- 2026-04-16
- Publication Date
- 2026-06-19
AI Technical Summary
In existing technologies, the prediction of tube rupture in waste heat boilers in dry quenching systems relies on the operator's experience, leading to misjudgments and omissions, which affect production safety.
An inert gas circulation pipeline is installed between the dry quenching furnace and the waste heat boiler, and equipped with pressure, hydrogen, and carbon monoxide sensors and a programmable controller. By monitoring the hydrogen, carbon monoxide concentration and pressure changes in real time, combined with data from the steam drum level and flow meter, intelligent prediction of tube rupture can be achieved.
It improves the accuracy of predicting tube rupture in waste heat boilers, reduces misjudgments and missed judgments, ensures safe system operation, and avoids explosion accidents.
Smart Images
Figure CN122237348A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a dry quenching coke circulation system, and more particularly to a method for predicting tube rupture in a waste heat boiler within the dry quenching coke circulation system. Background Technology
[0002] The core of a dry quenching (CDQ) system is a closed-loop heat exchange system using inert gas combined with waste heat recovery: red-hot coke at approximately 1000°C undergoes counter-current heat exchange with low-temperature inert gas, recovering heat to produce steam while cooling the coke. The entire system exhibits closed-loop energy-saving characteristics. The waste heat boiler in a CDQ system is typically a natural circulation water-tube boiler. Its core is the staged heat exchange between high-temperature inert gas and water or steam within the furnace, converting the heat from the 800–900°C inert circulating gas into high-temperature, high-pressure steam for power generation or heating. Waste heat boilers operate under conditions of high temperature, high pressure, dust, and corrosive media. Due to factors such as poor boiler water quality, boiler tube wear, and boiler tube scaling, waste heat... Water leaks and even tube ruptures are common in boilers. If a waste heat boiler ruptures, the high-temperature, high-pressure water (steam) will enter the closed-loop inert gas flow and then flow into the dry quenching furnace. When this water vapor encounters the high-temperature red-hot coke in the dry quenching furnace, it instantly vaporizes and decomposes into hydrogen and carbon monoxide, causing a sharp increase in the concentration of hydrogen (H2) and carbon monoxide (CO) in the circulating gas. This can lead to a series of drastic changes in production process parameters, making it impossible for the dry quenching system to operate normally. In severe cases, the rapid expansion of the gas volume in the furnace can directly cause a sharp increase in pressure in the pre-storage section at the top of the dry quenching furnace, resulting in an explosion.
[0003] Currently, in the operation of dry quenching systems, existing technologies rely mainly on the experience of operators to detect and determine tube rupture accidents. Due to the varying experience and skill levels of on-site operators, misjudgments and omissions frequently occur, leading to missed opportunities for optimal handling during production. Therefore, there is an urgent need to develop a scientific and intelligent method for judging boiler tube rupture, improving the accuracy of boiler tube rupture prediction, and ensuring the inherent safety of dry quenching systems. Summary of the Invention
[0004] This invention provides a method for predicting tube rupture in a waste heat boiler in a dry quenching system, which avoids misjudgment of boiler tube rupture and improves the accuracy of tube rupture prediction.
[0005] The present invention solves the above technical problems through the following technical solutions: A method for predicting tube rupture in a waste heat boiler in a dry quenching system includes a dry quenching furnace, a waste heat boiler, and a programmable controller (PLC). A pre-absorbed inert gas output pipeline and a pre-released inert gas input pipeline are respectively installed between the dry quenching furnace and the waste heat boiler. Inert gas circulates between the dry quenching furnace, the waste heat boiler, the pre-absorbed inert gas output pipeline, and the pre-released inert gas input pipeline. A first pressure sensor is installed in the red-hot coke pre-storage chamber at the top of the dry quenching furnace, and a second pressure sensor is installed at the circulating inert gas input end of the waste heat boiler. A hydrogen sensor and a carbon monoxide sensor are respectively installed in the pre-released inert gas input pipeline. The first pressure sensor, the second pressure sensor, the hydrogen sensor, and the carbon monoxide sensor are electrically connected to the PLC. The method is characterized by the following steps: If the hydrogen content in the inert circulating gas collected by the hydrogen sensor is greater than or equal to 3%, the carbon monoxide content in the inert circulating gas collected by the carbon monoxide sensor is greater than or equal to 8%, and the pressure in the red coke pre-storage chamber collected by the first pressure sensor is greater than or equal to 500 Pa, then it is predicted that a tube rupture has occurred in the waste heat boiler. If the hydrogen content in the inert circulating gas collected by the hydrogen sensor is greater than or equal to 3%, the carbon monoxide content in the inert circulating gas collected by the carbon monoxide sensor is greater than or equal to 8%, and the pressure in the waste heat boiler collected by the second pressure sensor is greater than or equal to 0 Pa, then it is predicted that a tube rupture has occurred in the waste heat boiler.
[0006] A steam drum level gauge is installed in the steam drum at the top of the waste heat boiler; if the steam drum level gauge drops below 100 mm, the degree of tube rupture in the waste heat boiler can be predicted more accurately.
[0007] A water flow meter is installed at the feedwater inlet of the waste heat boiler, and a steam flow meter is installed at the steam outlet of the waste heat boiler. During normal system operation, the difference between the water flow meter reading and the steam flow meter reading is the normal difference. If the difference between the water flow meter reading and the steam flow meter reading is greater than the normal difference, then the degree of tube rupture in the waste heat boiler can be further improved.
[0008] Based on experience in operating dry quenching systems, this invention has developed a set of practical intelligent judgment standards for predicting tube rupture in waste heat boilers. This avoids misjudgments, omissions, and operational errors caused by insufficient experience, negligence, and other human factors of on-site operators, thereby improving the reliability and consistency of emergency response data. Attached Figure Description
[0009] Figure 1 This is a schematic diagram of the structure of the present invention. Detailed Implementation
[0010] The present invention will now be described in detail with reference to the accompanying drawings: A method for predicting tube rupture in a waste heat boiler in a dry quenching system includes a dry quenching furnace 1, a waste heat boiler 2, and a programmable controller 12. A preheated inert gas output pipeline 3 and a preheated inert gas input pipeline 4 are respectively installed between the dry quenching furnace 1 and the waste heat boiler 2. Inert gas circulates between the dry quenching furnace 1, the waste heat boiler 2, the preheated inert gas output pipeline 3, and the preheated inert gas input pipeline 4. The dry quenching furnace 1, the preheated inert gas output pipeline 3, the waste heat boiler 2, and the preheated inert gas input pipeline 4 form a closed countercurrent heat exchange circulation system. 1000℃ red-hot coke first enters the dry quenching furnace 1 continuously from top to bottom through a red-hot coke pre-storage chamber, and the preheated inert gas flows from bottom to top. The inert gas continuously enters the furnace of the dry quenching furnace 1. After exchanging heat with the 1000℃ red-hot coke, it passes through the heat-absorbing inert gas output pipe 3 and enters the waste heat boiler 2. There, it exchanges heat with the water-cooled wall 13, superheater 14, evaporator 15, and economizer 16 before exiting from the bottom of the waste heat boiler 2. After passing through the heat-releasing inert gas input pipe 4, it re-enters the dry quenching furnace 1 to exchange heat with the 1000℃ red-hot coke. This cycle repeats, thus achieving the dry quenching of coke and the utilization of its heat. However, excessively high inert gas circulation speed, coke powder particles that are too coarse or have excessive hardness, the detachment of wear-resistant plates, and poor water quality can lead to scaling and corrosion in the water system, thus affecting the waste heat boiler. Leakage and pipe bursting occurred in the water circuit of the furnace. A first pressure sensor 5 was installed in the red coke pre-storage bin at the top of the dry quenching furnace 1 to monitor the pressure in real time. A second pressure sensor 6 was installed at the circulating inert gas input end of the waste heat boiler 2 to monitor the pressure inside the boiler furnace in real time. A hydrogen sensor 7 and a carbon monoxide sensor 8 were installed in the released inert gas input pipeline 4. Leaking boiler water in the waste heat boiler decomposes into hydrogen and carbon monoxide under high temperature and pressure. These gases, along with the circulating inert gas and undecomposed water vapor, first enter the released inert gas input pipeline 4, and then enter the furnace of the dry quenching furnace 1. The steam in the furnace of dry quenching furnace 1 will immediately decompose into hydrogen and carbon monoxide at a high temperature of around 800 degrees Celsius, causing a sharp increase in pressure inside the furnace and creating a significant explosion hazard. Therefore, pre-monitoring the concentration of hydrogen and carbon monoxide decomposed by the waste heat boiler is crucial for taking relevant measures in the early stages of a tube rupture, thus preventing explosion accidents. The first pressure sensor 5, the second pressure sensor 6, the hydrogen sensor 7, and the carbon monoxide sensor 8 are electrically connected to the programmable controller 12. An audible and visual alarm is connected to the programmable controller 12, which can issue different levels of alarm signals based on the following monitoring indicators to classify and indicate the degree of danger posed by the tube rupture in operation: If the hydrogen content in the inert circulating gas detected by the hydrogen sensor 7 is greater than or equal to 3%, or the carbon monoxide content in the inert circulating gas detected by the carbon monoxide sensor 8 is greater than or equal to 8%, then the audible and visual alarm connected to the programmable controller 12 will issue a first-level warning signal to pay close attention to the operating status of the waste heat boiler. If the hydrogen content in the inert circulating gas collected by the hydrogen sensor 7 is greater than or equal to 3%, and the carbon monoxide content in the inert circulating gas collected by the carbon monoxide sensor 8 is greater than or equal to 8%, then the audible and visual alarm connected to the programmable controller 12 will issue a secondary warning signal to pay close attention to the operating status of the waste heat boiler. If the hydrogen content in the inert circulating gas collected by the hydrogen sensor 7 is greater than or equal to 3%, the carbon monoxide content in the inert circulating gas collected by the carbon monoxide sensor 8 is greater than or equal to 8%, and the pressure in the red coke pre-storage bin collected by the first pressure sensor 5 is greater than or equal to 500 Pa, then if all three conditions are met, it is predicted that a tube rupture has occurred in the waste heat boiler, and the audible and visual alarm connected to the programmable controller 12 will issue a yellow alarm signal. If the hydrogen content in the inert circulating gas detected by hydrogen sensor 7 is greater than or equal to 3%, the carbon monoxide content in the inert circulating gas detected by carbon monoxide sensor 8 is greater than or equal to 8%, and the pressure in the waste heat boiler 2 detected by the second pressure sensor 6 is greater than or equal to 0 Pa, then it is predicted that a tube rupture has occurred in the waste heat boiler, and the audible and visual alarm connected to the programmable controller 12 will issue a yellow alarm signal; corresponding measures need to be taken on site. If the hydrogen content in the inert circulating gas collected by the hydrogen sensor 7 is greater than or equal to 3.5%, it is predicted that a tube rupture has occurred in the waste heat boiler, and the audible and visual alarm connected to the programmable controller 12 will issue a red alarm signal; corresponding measures need to be taken on site. If the carbon monoxide content in the inert circulating gas collected by the carbon monoxide sensor 8 is greater than or equal to 8%, it is predicted that a tube rupture has occurred in the waste heat boiler; the audible and visual alarm connected to the programmable controller 12 will issue a red alarm signal; corresponding measures need to be taken on site.
[0011] A steam drum level gauge 9 is installed in the steam drum at the top of the waste heat boiler 2. If the steam drum level gauge 9 drops to below 100 mm, the degree of tube rupture in the waste heat boiler is increased, and the audible and visual alarm connected to the programmable controller 12 issues the highest level red alarm signal, requiring immediate shutdown measures to be taken on site.
[0012] A water flow meter 10 is installed at the water inlet of the waste heat boiler 2, and a steam flow meter 11 is installed at the steam outlet of the waste heat boiler 2. During normal operation of the system, the difference between the reading of the water flow meter 10 and the reading of the steam flow meter 11 is the normal difference. If the difference between the reading of the water flow meter 10 and the reading of the steam flow meter 11 is greater than the normal difference, the degree of tube rupture in the waste heat boiler should be further improved, and the shutdown measures should be taken immediately on site. A primary dust collector 17 is installed on the heat-absorbing inert gas outlet pipeline 3, and a heat pipe heat exchanger 18, a circulating fan 19, and a secondary dust collector 20 are connected in series on the heat-releasing inert gas inlet pipeline 4.
Claims
1. A method for predicting tube rupture in a waste heat boiler in a dry quenching system, comprising a dry quenching furnace (1), a waste heat boiler (2), and a programmable controller (12), wherein an inert gas output pipeline (3) for absorbed heat and an inert gas input pipeline (4) for released heat are respectively provided between the dry quenching furnace (1) and the waste heat boiler (2), and inert gas circulates between the dry quenching furnace (1), the waste heat boiler (2), the inert gas output pipeline (3), and the inert gas input pipeline (4); a first pressure sensor (5) is provided in the red coke pre-storage bin at the top of the dry quenching furnace (1), and a second pressure sensor (6) is provided at the inert gas input end of the waste heat boiler (2); a hydrogen sensor (7) and a carbon monoxide sensor (8) are respectively provided in the inert gas input pipeline (4); the first pressure sensor (5), the second pressure sensor (6), the hydrogen sensor (7), and the carbon monoxide sensor (8) are electrically connected to the programmable controller (12); characterized in that: If the hydrogen content in the inert circulating gas collected by the hydrogen sensor (7) is greater than or equal to 3%, the carbon monoxide content in the inert circulating gas collected by the carbon monoxide sensor (8) is greater than or equal to 8%, and the pressure in the red coke pre-storage chamber collected by the first pressure sensor (5) is greater than or equal to 500 Pa, then it is predicted that a tube rupture phenomenon has occurred in the waste heat boiler. If the hydrogen content in the inert circulating gas collected by the hydrogen sensor (7) is greater than or equal to 3%, the carbon monoxide content in the inert circulating gas collected by the carbon monoxide sensor (8) is greater than or equal to 8%, and the pressure in the waste heat boiler (2) collected by the second pressure sensor (6) is greater than or equal to 0 Pa, then it is predicted that a tube rupture phenomenon has occurred in the waste heat boiler.
2. A method for predicting a tube burst in a waste heat boiler in a dry quenching system according to claim 1, a drum level meter (9) is arranged in the drum at the top of the waste heat boiler (2); characterized in that, If the steam drum level gauge (9) drops below 100 mm, then the prediction of tube rupture in the waste heat boiler will be improved.
3. The method according to claim 2, wherein a water flow meter (10) is arranged at the feedwater input end of the waste heat boiler (2), and a steam flow meter (11) is arranged at the steam output end of the waste heat boiler (2); during normal operation of the system, the difference between the reading of the water flow meter (10) and the reading of the steam flow meter (11) is a normal difference; characterized in that, If the difference between the reading of the water flow meter (10) and the reading of the steam flow meter (11) is greater than the normal difference, then the degree of tube rupture in the waste heat boiler will be further improved.