How to Handle Explosion-Proof System Alarms of Catalytic Combustion Equipment

When the explosion-proof system of catalytic combustion equipment triggers an alarm, on-site operators must follow standardized safety procedures to avoid explosion risks and secondary accidents. Catalytic combustion (RCO) is widely used for VOCs organic waste gas treatment in many manufacturing workshops. Its built-in explosion-proof system relies on LEL gas sensors, temperature transmitters, pressure monitoring units and interlock valves to monitor abnormal conditions in real time. Zhengzhou Puhua Technology is a professional environmental protection equipment manufacturer in Henan, focusing on the design, R&D and production of VOCs waste gas treatment equipment, RCO catalytic combustion equipment, RTO equipment, bag dust collectors, desulfurization and denitrification equipment, sewage treatment equipment and other environmental protection systems. The explosion-proof safety configuration of its catalytic combustion products is designed according to industrial safety specifications, and the alarm response guide below comes from years of on-site service experience.

1. Immediate Emergency Actions After Alarm Triggering

Once the explosion-proof alarm sounds, safety is the first priority. Operators should not rush to reset the alarm or check the equipment blindly. Follow these ordered steps:

1. Notify all personnel in the hazardous area and keep non-essential staff away from the catalytic combustion unit and waste gas pipeline area.

2. Confirm the automatic interlock action of the system: check whether the waste gas inlet valve is closed, the fresh air dilution valve is opened, and the dilution fan starts to dilute the combustible gas concentration.

3. Record alarm information clearly, including alarm time, alarm type, real-time LEL reading, temperature value and operating condition of the production line.

4. Stop the waste gas source if the gas concentration keeps rising, and suspend the front production process that discharges organic waste gas.

5. Do not operate mobile phones, non-explosion-proof electrical switches or open flames near the equipment during the alarm period.

2. Classify Alarm Types and Corresponding Disposal Methods

Explosion-proof alarms of catalytic combustion equipment are divided into concentration alarm, over-temperature alarm, pressure abnormal alarm and sensor fault alarm. Different alarm types have different handling logic.

3. Troubleshooting Checklist for Common False Alarms

Not all explosion-proof system alarms are caused by real dangerous conditions. False alarms often trouble workshop operation teams. You can check the following items one by one after the site enters a safe state:

• Check whether the gas sensor probe is covered with dust, oil mist or sticky particulate matter, which affects detection accuracy.

• Check signal cables and terminal blocks for moisture, loose contact or short circuit.

• Confirm whether the sensor has exceeded the calibration cycle. Long-term use will cause reading drift and false triggering.

• Check whether the installation position of the detector is unreasonable, affected by air flow or local solvent volatilization.

• Check whether the control program parameters were modified without authorization, resulting in improper alarm threshold setting.

Zhengzhou Puhua Technology reminds users that shielding or bypassing the explosion-proof interlock device to avoid alarms is an unsafe operation and will bring huge hidden dangers to the whole VOCs treatment system. Any modification of interlock logic needs to be evaluated by professional technical personnel.

4. Rules for Restarting Catalytic Combustion Equipment After Alarm

Many operators make the mistake of resetting the alarm and restarting the equipment immediately after the sound and light prompt disappears. The restart can only be carried out after all the following conditions are met:

• LEL concentration, bed temperature and pipeline pressure keep stable within the safe threshold for a continuous period.

• The root cause of the alarm has been found and eliminated completely.

• All explosion-proof components including sensors, interlock valves, flame arrestors and dilution fans work normally through inspection.

• Alarm records and handling reports are filed, and the workshop safety manager approves restart.

If the alarm reason cannot be located on site, stop restart attempt and contact the technical support team of the equipment supplier. Zhengzhou Puhua Technology provides after-sales inspection, maintenance and technical guidance services for RCO catalytic combustion equipment, RTO equipment and other VOCs governance systems, helping customers standardize explosion-proof management.

5. Daily Maintenance to Reduce Explosion-Proof Alarm Risks

Good daily maintenance can effectively reduce unexpected explosion-proof alarms and extend the service life of the explosion-proof monitoring system. Regular maintenance work includes:

1. Clean the sensor probe and pressure sampling pipeline periodically to prevent blockage by dust and tar.

2. Calibrate combustible gas detectors and temperature transmitters according to the maintenance cycle.

3. Check the action reliability of emergency cut-off valves and fresh air dilution valves every month.

4. Clean the catalyst layer regularly to avoid coking and local overheating.

5. Organize operators to conduct emergency drill for explosion-proof alarm response every quarter.

6. Frequently Asked Questions

Can I disable the explosion-proof alarm temporarily during production peak?

It is not allowed. The explosion-proof alarm and interlock system is the core safety barrier of catalytic combustion equipment. Disabling it will directly expose the waste gas treatment system to explosion risk. If alarms happen frequently, find out the root cause and optimize the waste gas collection or pretreatment system instead of turning off the alarm function.

What is the difference between the explosion-proof system of RCO and RTO equipment?

Both RCO and RTO belong to thermal oxidation VOCs treatment equipment and adopt LEL concentration monitoring as the core explosion-proof measure. RCO catalytic combustion runs at relatively lower temperature, while RTO regenerative thermal oxidation has higher temperature requirements. Zhengzhou Puhua Technology matches corresponding explosion-proof monitoring schemes for both types of equipment according to working conditions.

Conclusion

Handling explosion-proof system alarms of catalytic combustion equipment follows a core logic: emergency isolation first, classification investigation second, and restart only after hidden danger elimination. Standard alarm response and routine maintenance can protect personnel safety and stable operation of the VOCs treatment system. As a supplier of complete environmental protection equipment including catalytic combustion equipment, dust removal equipment, desulfurization and denitrification equipment and sewage treatment equipment, Zhengzhou Puhua Technology supports customers to formulate site-specific safety operation specifications for waste gas treatment.