Cause Analysis of Abnormal Temperature Rise in Catalytic Combustion Equipment

Many factories using catalytic combustion equipment for VOCs waste gas treatment encounter unexpected abnormal temperature rise during daily operation. Uncontrolled temperature rise may damage the catalyst, reduce waste gas purification efficiency, and bring potential safety risks to the whole VOCs treatment system. Operators need to identify root causes quickly and take targeted maintenance actions. Zhengzhou Puhua Technology, an environmental equipment manufacturer focusing on design, research, development and production of waste gas and wastewater treatment equipment, has accumulated rich practical experience in RCO catalytic combustion equipment, RTO equipment and other VOCs governance projects. This article sorts out the common causes, troubleshooting steps and preventive measures of catalytic combustion equipment overheating to help field operation teams solve temperature abnormality problems.

1. Process condition changes of inlet waste gas

The fluctuation of waste gas parameters is one of the most common triggers for abnormal temperature rise of catalytic combustion equipment. The catalytic oxidation reaction releases heat when VOCs are decomposed. Once the heat generation exceeds the heat dissipation capacity of the system, the bed temperature will climb rapidly.

• Sudden VOCs concentration spike: When the concentration of organic waste gas rises sharply beyond the design range of the equipment, a large amount of heat is released in a short time, forming hot spots on the catalyst bed. This situation often occurs during the desorption stage of activated carbon adsorption devices.

• Unstable waste gas flow rate: Too low air volume reduces the heat carrying capacity of gas flow. Heat cannot be taken out of the reaction chamber smoothly, leading to heat accumulation inside the catalytic bed.

• Special waste gas composition: High boiling point organic substances are easy to polymerize and form coke deposits on the catalyst surface, which creates local overheating points and further aggravates temperature deviation.

2. Catalyst performance degradation and bed blockage

The catalyst is the core component of RCO catalytic combustion equipment. Its working state directly affects the stability of reaction temperature.

1. Catalyst coking and fouling: Dust, tar and polymer impurities cover the catalyst surface, blocking the reaction channel. The heat generated by oxidation cannot transfer evenly, resulting in local high temperature.

2. Catalyst poisoning: Sulfur, phosphorus and halogen substances in waste gas will damage the active components of the catalyst. When activity declines, operators may increase heating power to maintain treatment effect, which indirectly pushes up the overall operating temperature.

3. Uneven catalyst filling: Uneven packing of catalyst will cause channeling of waste gas. Some areas bear excessive reaction load and form persistent high temperature zones.

3. Heat exchange system failure

The heat exchanger is responsible for heat recovery and balance inside catalytic combustion equipment. When the heat exchange function weakens, the residual heat cannot be recycled or exported normally.

4. Control system and component malfunction

Even if the reaction process and catalyst are normal, faults in sensing and control hardware will also cause false feedback and abnormal temperature adjustment.

• Temperature sensor drift or damage: The sensor feeds back wrong low temperature signal to PLC control system. The control system continuously increases electric heating power according to the error data, leading to excessive temperature.

• Valve stuck or leakage: Air supply valve, cold air dilution valve cannot open and close normally. The system fails to trigger cooling protection when temperature exceeds threshold.

• Improper parameter setting: Unreasonable setting of desorption time, heating upper limit and interlock protection parameters will cause continuous heat input without timely cut-off.

5. Systematic equipment maintenance recommendations

Regular inspection and maintenance can effectively reduce the probability of abnormal temperature rise of catalytic combustion equipment. Zhengzhou Puhua Technology provides complete supporting technical services for its RCO catalytic combustion equipment, RTO equipment, VOCs governance equipment, baghouse dust collectors, desulfurization towers, denitrification equipment and other environmental protection products, helping users establish standardized operation and maintenance systems.

1. Monitor VOCs concentration and gas flow in real time, install concentration interlock protection and cold air dilution mechanism to limit the concentration of waste gas entering the catalytic furnace within the designed safe range.

2. Check catalyst state periodically, clean surface coke or replace catalyst according to operating hours and waste gas condition.

3. Carry out regular cleaning for heat exchanger to remove dust and sticky dirt, keep good heat exchange performance.

4. Calibrate temperature sensors every certain cycle, test the action reliability of each pneumatic valve and safety interlock function.

5. Standardize the startup and shutdown operation procedure, avoid long-time high concentration desorption operation.

6. Conclusion

Abnormal temperature rise of catalytic combustion equipment is usually caused by the combined effect of waste gas condition, catalyst state, heat exchange performance and control system. Field engineers should check item by item according to the above logic instead of only adjusting temperature setting blindly. As a manufacturer of environmental protection equipment, Zhengzhou Puhua Technology covers dust removal equipment, desulfurization and denitrification equipment, VOCs organic waste gas treatment equipment, pneumatic conveying equipment and sewage treatment equipment. The company provides integrated solutions including scheme design, equipment manufacturing and after-sales technical guidance for industrial waste gas treatment projects. Scientific daily operation and regular maintenance can maintain stable operation of catalytic combustion equipment and reduce overheating risks in long-term VOCs treatment work.