Heating Furnace Management System

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Heating Furnace Management System I. General Provisions 1. Heating furnaces are important equipment in petrochemical production facilities, and they are also the devices that consume the most energy in such processes. In order to strengthen the management of heating furnaces, ensure their safe, stable, and long-term operation, and effectively carry out efforts to save energy and reduce consumption, this management system is formulated in accordance with the Group Company’s \"Equipment Management Measures (Trial)\". 2. This management system applies to the tubular heating furnaces in the refining and chemical production units under XX Branch. 3. The quality inspection and acceptance of the operation, maintenance, and repair of heating furnaces shall be carried out in accordance with relevant regulations and standards such as SHS01001 \"Standards for the Good Condition of Petrochemical Equipment\", SHS01006 \"Procedures for the Maintenance and Repair of Tubular Heating Furnaces\", SHF0001 \"Methods for Determining the Efficiency of Petrochemical Tubular Furnaces\", and the Corporation’s \"Regulations on Strengthening the Inspection of Corrosion in Refining Units\". II. Management Responsibilities 1. Main responsibilities of the company’s equipment management department: The company’s equipment management department is the functional department in charge of heating furnaces, and it carries out tasks related to the management of these furnaces under the leadership of the deputy manager in charge. Implement **relevant laws, regulations, as well as the group company’s systems, provisions, rules, and standards regarding the management of heating furnaces; formulate the enterprise’s own management system for heating furnaces, and monitor its implementation. Responsible for reviewing the maintenance, upgrading, inspection, and repair plans for heating furnaces. Participate in the inspection and acceptance of the newly built tubular heating furnace. Participate in the analysis and handling of accidents involving tubular heating furnace equipment, review accident prevention measures, and supervise their implementation. Supervise and inspect the use and maintenance of heating furnaces throughout the company, as well as the management of documentation and the use and maintenance of safety accessories. Organize the promotion and application of new technologies, new processes, new equipment, and new materials to continuously improve the management level of heating furnaces. 2. Responsibilities of the equipment management departments in each secondary unit: They are responsible for organizing the implementation of the regulations, procedures, methods, standards, and notices issued by higher-level authorities regarding the management of heating furnaces. They also develop management systems for heating furnaces based on the actual conditions of their own units, and conduct regular inspections to ensure compliance with these systems. Responsible for the equipment management of the heating furnaces in this unit, and involved in energy-saving efforts for those furnaces. Regularly analyze the condition and existing problems of the furnace, and propose corrective measures. Organize or participate in the overall management of the design, procurement, manufacturing, installation, maintenance, technical renovation, upgrading, and accident handling related to heating furnaces and their associated equipment. Responsible for preparing and submitting plans for the major repairs, upgrades, inspections, and maintenance of heating furnaces. Establish and improve the records for heating furnaces as well as the main technical documents related to them. Participate in the inspection and acceptance of the newly built tubular heating furnace. Participate in the analysis and handling of accidents involving tubular heater equipment, propose preventive measures, and be responsible for their implementation. Responsible for the management and statistics of the heating furnace’s thermal efficiency. Promote the application of new technologies, new processes, new equipment, and new materials to continuously improve the management level of heating furnaces. Work with relevant departments to carry out training for operators of tubular heating furnaces. Organize the preparation and submission of various reports related to heating furnaces. 3. Responsibilities of the production and technical departments in each secondary unit: Responsible for energy conservation and optimized operation management of the heating furnaces. Responsible for preparing process technical documents such as the \"Process Card\" and \"Process Operation Procedures\" for tubular heating furnaces, as well as start-up and shutdown plans. Supervise and inspect the daily operation of tubular heating furnaces to ensure that all process parameters of such furnaces meet the requirements specified in these regulations. Organize or participate in the analysis and handling of production accidents in tubular heating furnaces, and review accident prevention measures as well as inspect their implementation. Organize relevant units to conduct regular quality analyses of fuel oil (gas), maintain records, and ensure that the quality parameters of fuel oil (gas) meet the specified requirements. It is required that the total sulfur content in the fuel gas should not exceed 100 ppm, and the total sulfur content in the fuel oil should not exceed 1%. Take measures to reasonably control the fuel temperature, ensuring that the Engler viscosity of the fuel does not exceed 4.5 E° ； The pressure of the fuel (gas) and steam systems must be stable ； The atomized steam should be superheated steam, and its pressure should be controlled to be 0.05 MPa higher than that of the fuel. Responsible for the statistics on fuel consumption in the heating furnace. Promote the application of new technologies, new processes, new equipment, and new materials to continuously improve the management level of heating furnaces. Responsible for energy-saving efforts in heating furnaces, organizing the analysis of causes, and implementing energy-saving measures. Work with relevant departments to carry out training for operators of tubular heating furnaces. 4. Responsibilities of the production scheduling departments in each secondary unit: Responsible for the scheduling of gas and fuel used in the heating furnace’s fuel system. Ensure that the heating furnace operates within the limits permitted by its design to meet the requirements of the production process; operation under conditions of excessive temperature, pressure, or load is strictly prohibited. 5. The safety and environmental protection department is responsible for investigating and handling accidents involving heating furnaces, and it conducts regular monitoring of the flue gas emissions from these furnaces in accordance with **standards and the indicators set by the Tianjin environmental protection department. 6. The human resources department shall be responsible for the on-the-job training, assessment, and certification of furnace operators. 7. The company’s Mechanical Research Institute is responsible for assisting the equipment management department in monitoring and evaluating the efficiency of heating furnaces. 8. The user unit is responsible for the operation and management of the heating furnace, as well as its daily maintenance. III. Management Requirements 1. Average thermal efficiency (hereinafter referred to as efficiency) of the heating furnace during normal operation: The efficiency of heating furnaces with a thermal load of 10 MW or more should be 87% or higher; for newly built heating furnaces, this efficiency should be 89% or higher (the efficiency of chemical cracking furnaces should be 92% or higher) ； The thermal efficiency of heating furnaces with a heat load of less than 10 MW should reach the designed value. 2. While improving the thermal efficiency of the heating furnace, corrosion caused by flue gas dew point should be avoided. The material feed temperature should be controlled properly to ensure that the wall temperature of the furnace tubes is higher than the dew point temperature of the flue gas. The equipment management departments of each secondary unit should organize regular monitoring of the flue gas dew point temperature of the heating furnaces. 3. To save energy and reduce consumption, the operation of the heating furnace should be controlled according to the following parameters: 3.1 The final exhaust gas temperature should generally not exceed 170°C. If the sulfur content in the fuel deviates significantly from the design value, calibration and flue gas dew point testing should be carried out to determine an appropriate flue gas emission temperature for the heater (which should generally be 20–30°C higher than the dew point temperature). 3.2 To ensure complete combustion, the CO content in the exhaust gases should be reduced as much as possible, generally not exceeding 100 ppm. The oxygen content in the flue gas at the top of the convection chamber should be controlled between 2% and 4% in gas-fired heaters ； The fuel heating furnace should be controlled at 3%–5%. The temperature of the outer wall of the heating furnace shall meet the requirements specified in the relevant design regulations. 4. To protect the environment and extend the service life of equipment, it is necessary to strictly control the quality of fuel and regulate the emission of pollutants in the flue gas. Emissions of pollutants must meet **the standards and the requirements set by local environmental protection authorities. 4.1 Low-NOx burners should be actively adopted to reduce the NOx content in the exhaust gases. 4.2 Effective measures should be taken to control the sulfur compound and solid particle contents in the fuel, in order to reduce the levels of sulfur compounds such as SO2 and SO3 sowie dust in the exhaust gases. The total sulfur content in the fuel gas should not exceed 100 ppm ； The total sulfur content in the fuel oil should not exceed 1%, and the solid particle content should not exceed 2000 ppm. If the sulfur compound content and solid particle content in the fuel do not meet the required standards, a plan should be developed and measures taken to ensure that these standards are met within a specified time frame. 5. Regular training and examinations on the knowledge required for operating heating furnaces should be conducted for the personnel who work with them; only those who pass these tests are allowed to operate the furnaces. 6. The heating furnace must be equipped with thermocouples, a vacuum gauge, and an on-line oxygen content analyzer, and their proper operation must be ensured. 7. Each heating furnace should be equipped with appropriate flue gas sampling points to facilitate the monitoring of its operating conditions. The settings and requirements for flue gas sampling points are provided in the appendix. 8. Regular quality analysis should be conducted on the fuel oil and fuel gas used in the heating furnace, a record sheet should be maintained, and these records should be submitted to the equipment management department on a monthly basis. 9. The fuel oil, fuel gas, and atomizing steam used in the heating furnace should be metered, with accuracy of measurement ensured. 10. Advanced control systems should be actively adopted to gradually achieve automatic control of the combustion conditions in the heating furnace. In production units controlled by DCS, the DCS should be able to display the thermal efficiency value of the heating furnace. 11. The protection and interlocking of the heating furnace shall comply with the company’s relevant management regulations. IV. Operation and Maintenance 1. Strictly adhere to the operating procedures and the process parameters of the heating furnace to ensure that it operates within the limits specified by its design. Operating under conditions of excessive temperature, pressure, or load is strictly prohibited; moreover, operation at too low a load should be avoided as much as possible (a too low load generally refers to one below 60% of the designed load). 2. When the heating furnace is operated under special care due to special reasons, the equipment management departments of each secondary unit shall organize the formulation of a special care plan, which shall be approved for implementation by the technical supervisors of each secondary unit. While carrying out the prescribed inspection tasks, the operators of the production facility must also strictly implement the requirements specified in the special care plan. 3. Strengthen the inspection and management of the operation of heating furnaces: 3.1 The managers of production facilities should carry out the following tasks: Conduct at least one inspection per day of the operation of the heating furnaces within their jurisdiction. The furnace efficiency should be checked once a week ； An analysis report on the operation of the heating furnace of this device should be prepared on a monthly basis. Based on the operating conditions of the heating furnace, determine whether charring has occurred and formulate a charring mitigation plan. 3.2 Operators of the production equipment should operate carefully to maintain the heating furnace in good working condition. It is necessary to improve the adjustment of the three valves and one plate (throttle, valve, air valve, flue damper) to ensure that the furnace chamber remains bright and free from turbidity, prevent the burner flame from being too long, too large, or producing smoke, and strictly prohibit tube licking. Try to keep as many burners burning simultaneously to maintain efficient operation. Conduct routine inspections in accordance with the following rules: (1) Inspect the burner, fuel oil (gas), and steam systems every 1 to 2 hours. Check the burner for coking, blockages, oil leakage, and ensure that the pilot light is lit properly ； Oil guns and gas guns should be cleaned and maintained regularly, and replaced promptly if any damage is detected ； The backup burner should have its air valves and steam valves closed ； Oil guns and gas guns that have been out of use for more than half a year should be removed, cleaned, and stored. ⑵ Check the feed and discharge systems of the heating furnace every 1–2 hours, including the flow control, branch flow control, pressure control, as well as whether the readings for flow rate, pressure, and temperature are normal; always be vigilant for any signs of flow deviation. Any abnormal situation must have its cause identified and addressed promptly. ⑶ Inspect the fire suppression steam system at each shift. Check whether the fire viewing windows, fire viewing ports, ignition ports, explosion-proof doors, manhole doors, and elbow box doors are airtight to prevent air leakage. Check whether the furnace frame steel structure and furnace steel plates are in good condition and tightly fitted, as well as whether there is any over-temperature. ⑷ During each shift, check the radiation furnace tubes for any abnormalities such as localized overheating, coking, overburning, cracking, bulging, or bending. Also, inspect whether the inner lining of the furnace has fallen off, whether there are any issues with the furnace’s internal components, and whether the instrument monitoring system is functioning properly. ⑸ During each shift, check whether the burner air adjustment system, damper plates, and flue dampers are functioning properly, as well as whether the exhaust fans and blowers of the waste heat recovery system are operating correctly. If a problem is detected, it should be reported and addressed promptly. ⑹ In heating furnaces equipped with soot blowers, soot blowing should be carried out regularly depending on the type of fuel and the degree of soot accumulation. The soot blower should be regularly checked for any faults and to ensure it operates smoothly. For those using steam soot blowers, the condensed steam must be removed before blowing soot. ⑺ The condition of the instruments should be checked once a day. All oxygen content analyzers should be calibrated at least once per quarter, and any issues identified should be addressed promptly. The test results should be submitted to the production facility for record-keeping. 4. The start-up and shutdown of the heating furnace must be carried out strictly in accordance with the process operating procedures. Before starting or stopping operations, a detailed and thorough plan must be formulated, which must then be reviewed and approved by the relevant departments. During shutdown, special care must be taken to prevent sulfides from catching fire on their own inside the convection chamber. For austenitic stainless steel furnace tubes that are prone to metathionite corrosion after shutdown, alkaline cleaning should be employed to avoid stress corrosion cracking. The equipment management departments of subordinate units should establish corresponding \"Management Procedures for Austenitic Stainless Steel Equipment During Shutdown and Maintenance\". V. Maintenance and Repair 1. The inspection and repair of heating furnaces shall be carried out in accordance with the \"Maintenance and Repair Procedures for Tubular Heating Furnaces\" (SHS01006). 2. Routine maintenance of the heating furnace should be strengthened, especially the maintenance of accessories such as exhaust fans, flue dampers, and soot blowers. Any issues detected should be repaired promptly to eliminate the faults, so as not to affect the normal operation of the heating furnace. 3. The equipment management department should, based on the results of routine maintenance as well as inspections and tests during shutdowns, carefully prepare a maintenance plan for the heating furnaces, ensuring that they are neither over-maintained nor under-maintained. 4. Whenever a major maintenance shutdown occurs, all oxygen content analyzers (including probes), thermocouples, and vacuum gauges (including probes) should be maintained and calibrated. 5. During shutdown for maintenance, it is necessary to inspect and test the furnace tubes. Testing items should be arranged according to the actual situation, and qualified testing agencies should be assigned to carry out the tests. The inspection items may include: ——Visual inspection and measurement ； ——Thickness and hardness measurement ； ——Surface metallographic inspection ； ——Ultrasonic testing, weld X-ray radiography testing, or other non-destructive testing methods ； ——Analysis of scale on the furnace tube surface, and formulation of preventive measures. 6. The projects that have been repaired should be strictly inspected and accepted in accordance with relevant regulations and standards. 7. During shutdown for maintenance, the ash cleaning of the radiant furnace tubes should be arranged for the fuel heating furnace. For convection furnace tubes, it is necessary to determine whether cleaning is required and what method to use for cleaning, based on the degree of ash accumulation. Heating furnaces that burn fuel gas should decide whether ash cleaning is necessary depending on the circumstances. 8. All newly installed or repaired refractory bricks and refractory concrete must be dried out in accordance with the corresponding furnace drying curves ； During furnace drying, the furnace tubes should be filled with the permitted medium for protection. 9. When shutting down the centrifugally poured furnace tubes in the radiation chamber of the cracking furnace and conversion furnace, it is necessary to ensure that the furnace tubes are not struck during the installation or removal of catalysts. Regular ultrasonic testing of the furnace tubes should be carried out, and safety assessments or replacements of the furnace tubes should be performed in a timely manner. The portion of the radiant furnace tube that extends outside the furnace chamber should be properly insulated to prevent stress corrosion damage. VI. Inspection and Assessment 1. The equipment management departments of each secondary unit shall conduct an inspection and assessment of the operation status of the heating furnaces on a monthly basis, in order to promote continuous improvement in the management and operational efficiency of these furnaces. The company’s Equipment Management Department should regularly organize relevant personnel to inspect the operating condition of the heating furnaces, and evaluate the results of these inspections. 2. The assessment criteria for furnace management should include: the compliance with relevant regulations and procedures regarding the furnace ； Heat efficiency of the heating furnace ； The on-site operation status of the heating furnace and the condition of its equipment. Appendix: Locations for Flue Gas Sampling Points and Relevant Considerations 1. Locations for setting flue gas sampling points: In radiation chambers – For multi-chamber heating furnaces with two or more radiation chambers, flue gas sampling points should be installed at corresponding locations in each radiation chamber, so as to check whether the air supply to each chamber is consistent; such points may not be necessary for single-chamber furnaces ； Before entering the convection chamber-----Use this point to check the actual amount of air supplied for combustion, and control the air flow to the burner; if sampling points are already available in the radiation chamber, they can be reused. After exiting the convection chamber-----use the excess air coefficient at this point to calculate the thermal efficiency of the heating furnace, and check for air leakage in the convection chamber ； When using a waste heat recovery system, flue gas sampling points should be installed before and after the air preheater or waste heat boiler ； The sampling point for the dew point temperature test is located at the outlet of the last stage of the heating surface; for heaters without a waste heat recovery system, it should be placed at the outlet of the convection chamber, while for heaters equipped with a waste heat recovery system, it is located at the outlet of the air preheater or the waste heat boiler. 2. Hole size measurement: (1) The diameter of the flue gas sampling hole shall be no less than 20 mm. (2) The inner diameter of the sampling port for dew point temperature testing shall be no less than 40 mm. 3. Precautions for installing flue gas sampling points: There should be no air leaks in the area surrounding the sampling point ； The sampling point should be located as close as possible at the narrowest part of the flue, so as to achieve a higher smoke flow velocity and ensure thorough mixing of the combustion products ； The sampling point should preferably extend to the middle of the flue gas flow cross-section; if this is not possible, the insertion length should be at least 500 mm. Multiple sampling can reduce measurement errors ； The sampling point for controlling combustion should not be placed after the convection chamber ； The sampling point for measuring thermal efficiency should be located in the non-turbulent area of the chimney, that is, it should not be placed in the region where flow direction changes ； For wide-section flues, multi-point sampling facilities should be installed, or a single-tube telescopic sampling method should be employed.