Method for analyzing damage sensitivity of heat engine of coke tower and calculating damage factor

Abstract

The invention relates to the technical field of coke tower heat engine damage, in particular to a coke tower heat engine damage sensitivity analysis and damage factor calculation method. According to the method, firstly, a solid foundation is provided for subsequent analysis and evaluation through comprehensive information collection; and then, a clear judgment logic is utilized, so that a high-risk condition can be quickly identified, and a high-sensitivity conclusion is directly given, and therefore, the evaluation efficiency and pertinence are improved. For the condition that the condition is not met, feature analysis is further carried out, and hierarchy and deepness of evaluation are embodied. And then calculation is carried out through a coke tower heat engine damage sensitivity calculation formula, so that quantitative analysis is carried out based on the collected data, and a more objective and accurate evaluation result is obtained. And finally correcting the heat engine damage factor of the coke tower according to the heat engine damage state and the inspection condition. Therefore, the method adopted by the invention is high in comprehensiveness and clear in logic, and effectively improves the accuracy of coke tower heat engine damage sensitivity analysis and damage factor calculation.

Description

Technical Field

[0001] The invention relates to the technical field of coke tower thermal engine damage, in particular to a coke tower thermal engine damage sensitivity analysis and damage factor calculation method. Background Art

[0002] The coking unit is an important oil refining unit that converts heavy oil and low-quality residual oil into light oil through heating cracking, polymerization and coking reactions to produce liquefied gas, light oil and coke. As the core equipment of the coking unit, the coke tower has complex and harsh operating conditions due to the requirements of the production process. The interaction of high temperature and periodic heating and cooling processes causes the coke tower to show different sensitivities to thermal mechanical damage. The thermal mechanical damage sensitivity of the coke tower is an important criterion for measuring the safe operation status of the coke tower, and the two are negatively correlated.

[0003] At present, in order to understand the thermal mechanical damage sensitivity of the coke tower, the changes in the thermal mechanical damage sensitivity of the coke tower during operation are usually simulated by finite element analysis and other methods to determine the operating stability of the coke tower under current working conditions. During the operation of the coke tower, there are many factors that affect its thermal mechanical damage sensitivity, such as the material of the coke tower, the temperature rise rate in the coke tower, the maximum temperature in the coke tower, the cooling rate in the coke tower, and the process cycle in the coke tower. However, in the process of using finite element analysis in the above-mentioned prior art, due to the limited hardware computing power of the finite element analysis, only one or several factors are often considered. This method leads to an incomplete analysis, resulting in poor accuracy of the thermal mechanical damage sensitivity analysis results, which does not conform to the actual operation of the coke tower.

[0004] It can be seen that at this stage, more influencing factors need to be considered to analyze the coke tower in order to improve the accuracy of the analysis. Summary of the invention

[0005] In order to avoid and overcome the technical problems existing in the prior art, the present invention provides a coke drum thermal engine damage sensitivity analysis and damage factor calculation method. The present invention can effectively improve the accuracy of the coke drum thermal engine damage sensitivity analysis results.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A method for analyzing the damage sensitivity of a coke tower thermal engine and calculating the damage factor comprises the following steps:

[0008] S1. Obtain the basic information of the coke tower, including the material of the coke tower, the temperature rise rate in the coke tower, the maximum temperature in the coke tower, the cooling rate in the coke tower, the process cycle in the coke tower, whether the coke tower has been damaged by overheating, and whether the coke tower has been stress-relieved;

[0009] S2. If the coke tower is damaged by overheating, the thermal damage sensitivity of the output coke tower is high sensitivity; if the coke tower is not damaged by overheating and stress relief has not been performed, the thermal damage sensitivity of the output coke tower is high sensitivity; if the coke tower is not damaged by overheating and stress relief has been performed, characteristic analysis is performed on other parameters in the basic data of the coke tower;

[0010] S3. Calculate the thermal mechanical damage sensitivity of the coke drum using the thermal mechanical damage sensitivity calculation formula of the coke drum according to the characteristic analysis results;

[0011] S4. Calculate and correct the thermal mechanical damage factor of the coke drum based on the calculation results of the thermal mechanical damage sensitivity of the coke drum and the overheating mechanical damage state of the coke drum.

[0012] As a further solution of the present invention: the calculation formula for the damage sensitivity of the coke tower thermal engine is as follows:

[0013] F = f1 + f2 + f3 + f4 + f5;

[0014] Where F represents the number of factors affecting the thermal mechanical damage sensitivity of the coke drum; f1 represents the material parameters of the coke drum; f2 represents the temperature rise rate parameter in the coke drum; f3 represents the maximum temperature parameter in the coke drum; f4 represents the cooling rate parameter in the coke drum; and f5 represents the process cycle parameter in the coke drum.

[0015] As a further solution of the present invention: the process of feature analysis is as follows:

[0016] S21. Determine the value of the material parameter of the coke drum according to the material type of the coke drum. When the material of the coke drum is chrome-molybdenum steel, f1=0; when the material of the coke drum is carbon-molybdenum steel or carbon steel, f1=1;

[0017] S22, determining the value of the temperature rise rate parameter in the coke drum according to the temperature rise rate in the coke drum, when the temperature rise rate in the coke drum is not greater than 70°C / h, f2=0; otherwise, f2=1;

[0018] S23, determining the value of the maximum temperature parameter in the coke drum according to the maximum temperature in the coke drum, when the maximum temperature in the coke drum is not greater than 500° C., f3=0; otherwise, f3=1;

[0019] S24, determining the value of the cooling rate parameter in the coke drum according to the cooling rate in the coke drum, when the cooling rate in the coke drum is not greater than 100°C / h, f4=0; otherwise, f4=1;

[0020] S25. Determine the value of the process cycle parameter in the coke drum according to the size of the process cycle in the coke drum. When the process cycle in the coke drum is not greater than 36 hours, f5=0; otherwise, f5=1.

[0021] As a further solution of the present invention: the thermal mechanical damage sensitivity of the coke drum is as follows:

[0022] When F = 0, the output coke tower thermal engine damage sensitivity is null sensitivity;

[0023] When F = 1 or 2, the thermal damage sensitivity of the output coke tower is low;

[0024] When F = 3 or 4, the output coke tower thermal engine damage sensitivity is medium sensitivity;

[0025] When F=5, the output coke tower thermal engine damage sensitivity is high.

[0026] As a further solution of the present invention: the specific steps of step S4 are as follows:

[0027] S41. Based on the thermal damage sensitivity of the coke drum, the thermal damage factor of the coke drum is determined according to the damage judgment principle:

[0028] S42. According to the number of times the coke drum is damaged by overheating, the thermal engine damage factor is corrected using a correction model.

[0029] As a further solution of the present invention: the damage judgment principle is as follows:

[0030] When the thermal damage sensitivity of the coke drum is high, the thermal damage factor D F =500;

[0031] When the thermal damage sensitivity of the coke drum is medium, the thermal damage factor D F =10;

[0032] When the thermal damage sensitivity of the coke drum is low, the thermal damage factor D F =1.

[0033] As a further solution of the present invention: the correction model is specifically expressed as follows:

[0034] D=D F ×D1;

[0035] D=D F ×D2;

[0036] Where D represents the corrected thermal mechanical damage factor; D1 represents the thermal mechanical damage parameter of the coke drum; D2 represents the correction parameter of the number of inspections of the coke drum when the coke drum has no thermal mechanical damage;

[0037] When the number of thermal mechanical damages in the coke drum is 1, D1 = 0.1;

[0038] When the number of thermal mechanical damages to the coke drum is more than 2 times, D1 = 1;

[0039] When the number of inspections of the coke drum is 0, D2 = 1;

[0040] When the number of inspections in the coke drum is 1, D2 = 0.5;

[0041] When the number of inspections of the coke drum is 2, D2 = 0.2;

[0042] When the coke drum is tested more than 3 times, D2=0.1.

[0043] As a further solution of the present invention: the minimum value of the corrected thermal engine damage factor is 1.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] 1. The present invention first comprehensively collects the basic data of the coke tower through step S1. These basic data cover multiple key factors that affect the thermal damage sensitivity of the coke tower, such as materials, temperature change rate, process cycle, damage and stress relief status, etc. This comprehensive information collection provides a solid foundation for subsequent analysis and evaluation. Then step S2 sets a clear judgment logic, that is, first judge whether the coke tower has been overheated and has not been stress relieved. The establishment of this step can quickly identify high-risk situations and directly give a high sensitivity conclusion, thereby improving the efficiency and pertinence of the evaluation. For situations where this condition is not met, further feature analysis is performed, which reflects the hierarchy and depth of the evaluation. Step S3 mentions that the calculation is performed using the calculation formula for the thermal damage sensitivity of the coke tower, which shows that the evaluation process adopts scientific methods and tools, and can perform quantitative analysis based on the collected data to obtain more objective and accurate evaluation results. Step S4 mentions that the thermal damage factor of the coke tower is corrected according to the calculation results of the thermal damage sensitivity and the overheating damage status. This step reflects the dynamics and flexibility of the evaluation process, and can timely adjust and optimize the evaluation results according to the actual situation, so as to better reflect the real state of the coke drum. It can be seen that the method adopted by the present invention is highly comprehensive and logically clear, and effectively improves the accuracy of the coke drum thermal engine damage sensitivity analysis and damage factor calculation.

[0046] 2. The entire process design of the present invention is concise and clear, easy to understand and operate, and has strong practicality. Through this process, the thermal mechanical damage sensitivity of the coke drum can be quickly and accurately evaluated, which helps to avoid the large differences in the thermal mechanical damage sensitivity and damage factor results of the coke drum due to different analysis and evaluation personnel, and facilitates the subsequent calculation of the failure possibility of the coke drum including the thermal mechanical damage mechanism.

[0047] 3. The main influencing factors causing the damage to the coke drum thermal engine are analyzed with reference to the present invention, and then targeted solutions are proposed for the equipment or process, which is helpful for relevant technical personnel to manage the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 It is a flow chart of the present invention. DETAILED DESCRIPTION

[0049] 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.

[0050] See also Figure 1 , the present invention mainly includes the following contents.

[0051] Step 1: Obtain the basic information of the coke tower, including the material of the coke tower, the temperature rise rate in the coke tower, the maximum temperature in the coke tower, the cooling rate in the coke tower, and the process cycle in the coke tower.

[0052] Step 2: Confirm whether the coke drum has overheated engine damage: if it has, the output sensitivity is high, otherwise go to step 3. In the basic data of the coke drum, the historical operation records and inspection reports will clearly reflect whether the coke drum has overheated engine damage, as well as the specific morphology and description of the thermal engine damage.

[0053] Step 3: Confirm whether the coke tower has been stress-relieved: If not, the thermal mechanical damage sensitivity of the coke tower is output as high sensitivity, otherwise, step 4. In the basic data of the coke tower, the historical operation records and inspection reports will clearly reflect whether the coke tower has been heat-treated. If the heat treatment item in the basic data says that heat treatment has been carried out, it is considered that stress relief has been carried out.

[0054] Step 4: Conduct characteristic analysis: Analyze the factors affecting the thermal engine damage of the coke tower: f1, f2, f3, f4 and f5.

[0055] The process of feature analysis is as follows:

[0056] First, the value of the material parameter of the coke drum is determined according to the material type of the coke drum. When the material of the coke drum is chrome-molybdenum steel, f1=0; when the material of the coke drum is carbon-molybdenum steel or carbon steel, f1=1.

[0057] Then, the value of the temperature rise rate parameter in the coke drum is determined according to the temperature rise rate in the coke drum. When the temperature rise rate in the coke drum is not greater than 70°C / h, f2=0; otherwise, f2=1.

[0058] Then, the value of the maximum temperature parameter in the coke drum is determined according to the maximum temperature in the coke drum. When the maximum temperature in the coke drum is not greater than 500° C., f3=0; otherwise, f3=1.

[0059] Then, the value of the cooling rate parameter in the coke drum is determined according to the cooling rate in the coke drum. When the cooling rate in the coke drum is not greater than 100°C / h, f4=0; otherwise, f4=1.

[0060] Finally, the value of the process cycle parameter in the coke drum is determined according to the size of the process cycle in the coke drum. When the process cycle in the coke drum is not greater than 36 hours, f5=0; otherwise, f5=1.

[0061] Step 5: Substitute the characteristic analysis results in step 4 into the calculation formula for the thermal mechanical damage sensitivity of the coke drum as shown in formula (1), and calculate the thermal mechanical damage sensitivity of the coke drum in turn.

[0062] F=f1+f2+f3+f4+f5 (1)

[0063] Where F represents the number of factors affecting the thermal mechanical damage sensitivity of the coke drum; f1 represents the material parameters of the coke drum; f2 represents the temperature rise rate parameter in the coke drum; f3 represents the maximum temperature parameter in the coke drum; f4 represents the cooling rate parameter in the coke drum; and f5 represents the process cycle parameter in the coke drum.

[0064] The thermal mechanical damage sensitivity of the coke tower is as follows: when F=0, the output coke tower thermal mechanical damage sensitivity is null sensitivity; when F=1 or 2, the output coke tower thermal mechanical damage sensitivity is low sensitivity; when F=3 or 4, the output coke tower thermal mechanical damage sensitivity is medium sensitivity; when F=5, the output coke tower thermal mechanical damage sensitivity is high sensitivity.

[0065] Step 6: Based on the calculation results of the thermal mechanical damage sensitivity of the coke drum and the overheating mechanical damage state of the coke drum, the thermal mechanical damage factor of the coke drum is calculated using the damage judgment principle. The damage judgment principle is as follows:

[0066] When the thermal damage sensitivity of the coke drum is high, the thermal damage factor DF =500;

[0067] When the thermal damage sensitivity of the coke drum is medium, the thermal damage factor D F =10;

[0068] When the thermal damage sensitivity of the coke drum is low, the thermal damage factor D F =1.

[0069] Step 7: Correct the damage factor according to the operation and inspection conditions. According to the number of times the coke drum has been damaged by overheating, the thermal engine damage factor is corrected using the correction model shown in formula (2) and formula (3).

[0070] D=D F ×D1 (2)

[0071] D=D F ×D2 (3)

[0072] Where D represents the corrected thermal mechanical damage factor; D1 represents the thermal mechanical damage parameter of the coke drum; and D2 represents the correction parameter for the number of inspections of the coke drum when no thermal mechanical damage occurs to the coke drum.

[0073] When the number of thermal mechanical damages to the coke drum is 1, D1 = 0.1.

[0074] When the number of thermal mechanical damages to the coke drum is more than 2 times, D1=1.

[0075] When the number of inspections of the coke drum is 0, D2 = 1;

[0076] When the coke drum is inspected once, D2=0.5.

[0077] When the coke drum is tested twice, D2=0.2.

[0078] When the coke drum is tested more than 3 times, D2=0.1.

[0079] Step 8: Output the corrected thermal engine damage factor of the coke drum. The minimum value of the corrected thermal engine damage factor is 1.

[0080] Embodiment 1:

[0081] A petrochemical enterprise evaluated the delayed coking unit. By collecting and arranging the basic information of the coke tower in the unit, it was found that the coke tower had experienced thermal engine damage in its operation history. During the shutdown and major overhaul in a certain year, the main defects found were: 4 fractures at the spot welds between the gasket and the arch plate, and a 12mm long linear defect magnetic mark was found by magnetic particle inspection. It was eliminated by grinding and the depth was 2.5mm.

[0082] According to the above data, if the coke drum has overheated mechanical damage, the thermal mechanical damage sensitivity of the coke drum is high, and the thermal mechanical damage factor is 500. Since the number of thermal mechanical damage occurrences is greater than 1, the corrected thermal mechanical damage factor is still 500, which means that the equipment is more likely to suffer thermal mechanical damage in the future operation.

[0083] Embodiment 2:

[0084] A petrochemical enterprise conducted an evaluation of the delayed coking unit. By collecting and arranging the basic data of the coke tower in the unit, it was found that the coke tower had been inspected twice, no thermal mechanical damage had occurred, stress was eliminated through heat treatment, and the selected material was 14CrMoR. According to the actual monitored temperature changes, the temperature rise rate in the coke tower reached a maximum of 75℃ / h, the temperature drop rate reached a maximum of 130℃ / h, the highest temperature during deep reaction in the coke tower was 495~505℃, and the process production cycle was 42h. It can be seen that: f1=1, f2=1, f3=1, f4=1, f5=0, and the final number of influencing factors F=3, then the thermal mechanical damage sensitivity of the coke tower is medium sensitivity, and the thermal mechanical damage factor obtained is 100. Since the coke tower has been inspected twice, the corrected thermal mechanical damage factor is 100×0.2=20, which shows that the possibility of failure caused by thermal mechanical damage is reduced. It can also be seen from this case that the temperature control during the operation of the coke tower is relatively general. Therefore, it is recommended that relevant technical and process personnel should make process adjustments to the coke tower to optimize the temperature control during the production process.

[0085] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for analyzing the damage sensitivity of coke tower thermal machinery and calculating the damage factor. It is characterized in that The following steps are involved: S1. Obtain the basic information of the coke tower, including the material of the coke tower, the temperature rise rate in the coke tower, the maximum temperature in the coke tower, the cooling rate in the coke tower, the process cycle in the coke tower, whether the coke tower has been damaged by overheating, and whether the coke tower has been stress-relieved; S2. If the coke tower is damaged by overheating, the thermal damage sensitivity of the output coke tower is high sensitivity; if the coke tower is not damaged by overheating and stress relief has not been performed, the thermal damage sensitivity of the output coke tower is high sensitivity; if the coke tower is not damaged by overheating and stress relief has been performed, characteristic analysis is performed on other parameters in the basic data of the coke tower; S3, calculating the thermal mechanical damage sensitivity of the coke drum using a calculation formula for thermal mechanical damage sensitivity of the coke drum according to the characteristic analysis results after the characteristic analysis in step S2; S4. Calculate and correct the thermal mechanical damage factor of the coke drum according to the calculation result of the thermal mechanical damage sensitivity of the coke drum in step S3 and the overheating mechanical damage state of the coke drum.

2. A coke drum thermal mechanical damage sensitivity analysis and damage factor calculation method according to claim 1, It is characterized in that The calculation formula for the thermal mechanical damage sensitivity of the coke tower is as follows: F=f 1 +f 2 +f 3 +f 4 +f 5 ; Where, F represents the number of factors affecting the thermal mechanical damage sensitivity of the coke drum; f 1 Represents the material parameters of the coke tower; f 2 Indicates the temperature rise rate parameter in the coke tower; f 3 Indicates the maximum temperature parameter in the coke tower; f 4 Indicates the cooling rate parameter in the coke tower; f 5 Represents the process cycle parameters in the coke drum.

3. A coke tower thermal mechanical damage sensitivity analysis and damage factor calculation method according to claim 2, It is characterized in that The process of feature analysis is as follows: S21. Determine the value of the material parameter of the coke drum according to the material type of the coke drum. When the material of the coke drum is chrome-molybdenum steel, then f 1 =0; when the coke tower is made of carbon-molybdenum steel or carbon steel, then f 1 =1; S22. Determine the value of the temperature rise rate parameter in the coke drum according to the temperature rise rate in the coke drum. When the temperature rise rate in the coke drum is not greater than 70℃ / h, f 2 =0; otherwise, f 2 =1; S23. Determine the value of the maximum temperature parameter in the coke drum according to the maximum temperature in the coke drum. When the maximum temperature in the coke drum is not greater than 500°C, f 3 =0; otherwise, f 3 =1; S24. Determine the value of the cooling rate parameter in the coke drum according to the cooling rate in the coke drum. When the cooling rate in the coke drum is not greater than 100℃ / h, f 4 =0; otherwise, f 4 =1; S25. Determine the value of the process cycle parameter in the coke drum according to the process cycle size in the coke drum. When the process cycle in the coke drum is not greater than 36 hours, then f 5 =0; otherwise, f 5 =1.

4. A coke drum thermal mechanical damage sensitivity analysis and damage factor calculation method according to claim 3, It is characterized in that The thermal mechanical damage sensitivity of the coke drum is as follows: When F = 0, the output coke tower thermal engine damage sensitivity is null sensitivity; When F = 1 or 2, the thermal damage sensitivity of the output coke tower is low; When F = 3 or 4, the output coke tower thermal engine damage sensitivity is medium sensitivity; When F=5, the output coke tower thermal engine damage sensitivity is high.

5. A coke drum thermal mechanical damage sensitivity analysis and damage factor calculation method according to any one of claims 1 to 4, It is characterized in that The specific steps of step S4 are as follows: S41. Based on the thermal damage sensitivity of the coke drum, the thermal damage factor of the coke drum is determined according to the damage judgment principle: S42. According to the number of times the coke drum is damaged by overheating, the thermal engine damage factor is corrected using a correction model.

6. A coke drum thermal mechanical damage sensitivity analysis and damage factor calculation method according to claim 5, It is characterized in that The principles for judging damage are as follows: When the thermal damage sensitivity of the coke drum is high, the thermal damage factor D F =500; When the thermal damage sensitivity of the coke drum is medium, the thermal damage factor D F =10; When the thermal damage sensitivity of the coke drum is low, the thermal damage factor D F =1.

7. A coke drum thermal mechanical damage sensitivity analysis and damage factor calculation method according to claim 6, It is characterized in that The modified model is specifically expressed as follows: D=D F ×D 1 ; D=D F ×D 2 ; Where D represents the corrected thermal damage factor; D 1 represents the thermal mechanical damage parameter of the coke drum; D 2 Indicates the correction parameter of the number of inspections of the coke drum when there is no thermal mechanical damage to the coke drum; When the number of thermal mechanical damages in the coke drum is 1, D 1 =0.1; When the number of thermal mechanical damages to the coke drum is more than 2 times, D 1 =1; When the number of tests in the coke tower is 0, D 2 =1; When the number of inspections in the coke drum is 1, D 2 =0.5; When the number of inspections of the coke tower is 2, D 2 =0.2; When the number of inspections of the coke drum is more than 3 times, D 2 =0.

1.

8. A coke drum thermal mechanical damage sensitivity analysis and damage factor calculation method according to claim 7, It is characterized in that The minimum value of the corrected thermal mechanical damage factor is 1.

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