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Operating Procedures for Honeycomb Electrostatic Tar Collector 1. Working Principle: Gas containing tar mist enters the electrostatic tar collector through the inlet located on the outer shell below the sedimentation electrode. The distribution plate ensures even distribution of the gas; as the gas passes through the electrode area, the tar droplets in the gas are separated under the action of an electric field. The purified gas exits the electrostatic tar catcher through the upper outlet, while the separated tar droplets flow downward along the honeycomb-shaped sedimentation electrodes and are discharged from the bottom. The high-voltage current from the high-voltage rectifier passes through high-voltage cables and is fed, via the feed box, to the brackets of the discharge system located in the insulating box. The discharge system relies on the insulator posts in the insulating box, as well as the upper and lower brackets, to ensure that each corona electrode is positioned at the center of each cellular space. To prevent contamination of the insulating porcelain insulators by gas, which could lead to grounding or explosions, nitrogen is used for protection inside the insulating box; at the same time, nitrogen is introduced at the bottom of the insulators to isolate them from the gas. Furthermore, to prevent dew formation on the surface of the insulators, jacket steam heating is provided inside the insulation box. 2. Process parameters 2.1 The operating primary voltage of the honeycomb electrostatic tar catcher is ≤300V, while the secondary voltage is 28–42 KV. The operating primary current is ≤150A, and the secondary current ranges from 300–1200mA. 2.2 The oxygen content in the gas inlet of the honeycomb electrostatic tar catcher shall be ≤ 2.0% ； 2.3 Temperature of the insulation box in the honeycomb electrostatic tar catcher: 80–100℃ ； 2.4 The nitrogen flow rate introduced at the bottom of the porcelain bottle is 50–80 m3/h ； 2.5 The design pressure of the honeycomb electrostatic tar catcher is 0.03 Mpa, while the operating pressure is 0.02 Mpa. 3. Operating Procedures 3.1 Startup Procedure for Cellular Electrostatic Tar Catchers 3.1.1 For normal startup and switching of electrostatic tar catchers, it is necessary to report to the control room, with the shift supervisor providing direction. 3.1.2 The electrician checks to ensure that the electrical system is in good condition, and the process system prepares for operation. 3.1.3 Verify that the electric and manual controls of the gas valve are functioning properly, that the liquid discharge pipeline is unobstructed, and that the valves on the vent pipe and connection pipes at the top of the tank are open. 3.1.4 Slowly introduce steam into the insulation box jacket to maintain the temperature inside the insulation box at 80–100°C. 3.1.5 Drain the water accumulated in the nitrogen pipe, open the vent pipe at the top of the insulation box, and open the nitrogen valve feeding into the insulation box to replace the air inside the box. 3.1.6 Nitrogen is introduced at the bottom of the electrostatic precipitator to displace the gas inside the vessel; a gas sample is taken from the vent pipe at the top of the cylinder for nitrogen analysis. Once the analysis shows satisfactory results, the nitrogen valve at the bottom of the electrostatic precipitator is closed. Adjust the vent pipe at the top of the insulation box, and adjust the nitrogen valve feeding nitrogen into the insulation box to ensure continuous nitrogen supply therein, maintaining a nitrogen pressure of 0.015–0.02 MPa; check this pressure every 30 minutes. Close the vent pipe at the top of the cylinder, close the connecting pipe valve, and fully open the gas outlet valve and the gas inlet valve. Open the nitrogen valve at the bottom of the porcelain bottle and control the flow rate at 50–80 m3/h. 3.1.7 Verify that the blower and electrostatic precipitator are operating properly; ensure that the oxygen content in the gas remains below 2.0% for 1 hour continuously. The electrician shall supply power, adjust the voltage as required, stabilize it, and report to the control room. 3.1.8 Strengthen inspections and keep proper records. 3.2 Shutdown procedure for honeycomb electrostatic tar collectors 3.2.1 Report to the control room, with the shift supervisor providing direction. 3.2.2 Notify the electrician to cut off the power supply and hang a shutdown sign. 3.2.3 Close the gas inlet and outlet valves, open the top vent pipe, and open the connecting pipe. 3.2.4 Open the nitrogen valve at the bottom of the electrostatic tar catcher to fill it with nitrogen, maintaining the pressure inside the container at 0.02–0.03 Mpa. 4. Conditions for shutting down the electrostatic tar catcher due to power loss 4.1 Stop the nitrogen supply. 4.2 The temperature of the insulation box is below 80°C. 4.3 Stoppage or switching of the blower. 4.4 Oxygen content in gas: two verifications, >2.0%. 4.5 The electrical equipment has obvious faults and cannot remain operational; arcs and network issues cannot be detected or eliminated. 5. Prohibited Practices 5.1 It is strictly prohibited to operate the electrostatic tar catcher with excessive voltage or excessive gas pressure. 5.2 It is strictly prohibited to operate the electric tar catcher when the oxygen content in the gas exceeds 2.0%. 6. Special Operations 6.1 In the event of a power outage, quickly turn off the switch of the electrostatic tar catcher, close the gas inlet valve, inform the shift supervisor and the control room, and ask the electrician to get ready to restart the equipment. 6.2 When stopping the nitrogen supply, quickly pull the switch of the electrostatic tar catcher, close the gas inlet valve, and inform the shift supervisor to resume operations according to normal procedures. 6.3 In the event of a power outage in the instrumentation system and it becomes impossible to monitor the oxygen content in the gas at the inlet of the electrostatic precipitator, the shift supervisor should be informed; the switch for the electrostatic precipitator should be turned off, as well as the gas inlet valve. 6.4 When stopping the steam supply, if the temperature inside the insulation box is below 80°C, turn off the switch of the electric tar catcher, close the gas inlet valve, inform the shift supervisor, and prepare to resume normal operations. 6.5 When cleaning the porcelain cylinder, turn off the switch of the electric tar catcher, close the gas inlet and outlet valves, verify that the valves are properly closed by checking the pressure, purge the cylinder and the insulation box with nitrogen, and take samples from the vent pipes at the top of the cylinder and insulation box for nitrogen content analysis; only after the results are satisfactory can the insulation box be opened. 6.6 In the event of grounding in the electric precipitator, promptly turn off the switch for the electric tar precipitator, close the gas inlet and outlet valves, verify that the valves are properly closed by checking the pressure, and use nitrogen to purge the tank and the insulation box.