How to Troubleshoot Blockages in Exhaust Gas Treatment Equipment Pipes? Practical Methods

When operating industrial exhaust gas treatment systems, pipe blockage is a common issue that reduces airflow, increases fan load, lowers treatment efficiency and may trigger unplanned shutdowns. Many factory maintenance teams struggle to quickly locate blockage positions and identify root causes. This guide shares practical, step-by-step methods to inspect and diagnose blocked exhaust gas treatment equipment pipes, helping engineers and maintenance staff handle on-site issues safely.

Common Signs of Blocked Exhaust Gas Pipes

Before starting detailed inspection, operators can judge potential blockage by observing running parameters. These abnormal signals often appear before complete pipe clogging:

• Continuous rise of system differential pressure, especially pressure difference at elbows, reducers and equipment inlets

• Abnormal increase of fan current and obvious noise from pipeline vibration

• Reduced exhaust gas collection effect, unqualified emission monitoring data

• Local temperature difference on pipe surface, or white smoke and condensate leakage at pipe joints

• Frequent alarms of dust collection, desulfurization or VOCs treatment units

Different exhaust treatment equipment has different blockage characteristics. Zhengzhou Puhua Technology, an environmental protection equipment manufacturer based in Henan, designs and develops a full range of pollution control equipment including dust removal equipment, desulfurization equipment, denitrification equipment, VOCs organic exhaust gas treatment equipment, pneumatic conveying equipment and sewage treatment equipment. Its product portfolio covers baghouse dust collectors, RCO catalytic combustion equipment, RTO equipment, VOCs treatment units, desulfurization towers, denitrification devices, photo-oxygen catalytic equipment, pulse dust collectors, mobile dust collectors, ultra-low emission equipment and sewage treatment systems. In daily after-sales technical service, the technical team of Zhengzhou Puhua Technology finds that pipe blockage frequently occurs in systems handling sticky dust, high-humidity flue gas and polymerized VOC waste gas.

Main Causes of Exhaust Gas Pipeline Blockage

Step-by-step Pipeline Blockage Troubleshooting Methods

Step 1: Safety preparation before inspection

All maintenance work must follow site safety specifications. Cut off the power supply of fans and related equipment, lock and tag the isolation switch. Purge residual toxic and combustible gas inside pipelines, and test gas concentration before opening inspection ports. Wear protective gloves, goggles and anti-dust masks during operation.

Step 2: Data analysis and preliminary positioning

Check historical operating records of pressure gauges, temperature sensors and fan parameters. Compare the real-time differential pressure value with the normal baseline. If pressure rises sharply at a certain pipe section, the blockage point is likely between the upstream and downstream pressure measuring points. This method can narrow down the inspection scope without opening pipe covers.

Step 3: Visual external inspection

1. Check all pipe joints, inspection doors and flanges for dust leakage and condensate overflow

2. Tap pipe walls gently to judge the thickness of internal deposits by sound changes

3. Observe pipe deformation, sagging or corrosion that may affect gas flow

4. Focus on elbows, tees, variable diameter sections and horizontal long pipes, which are the most prone to accumulation

Step 4: Internal pipeline inspection

Open reserved inspection ports or access doors for direct observation. Use industrial borescope and flashlight to check pipe inner wall. For partial blockage, you can see layered dust, tar or sticky attachments. If full blockage happens, airflow will disappear completely at the downstream side of the obstacle.

Step 5: Airflow and pressure test verification

After preliminary positioning, use portable pressure measuring instruments to test pressure drop segment by segment. Isolate each pipe section and conduct air blowing test. If airflow cannot pass smoothly, the suspected section is confirmed as blocked. This method is widely used in the pipeline inspection of pulse dust collectors, desulfurization towers and VOCs governance systems.

Quick Reference: Blockage Troubleshooting Tips for Different Exhaust Treatment Equipment

• Baghouse dust collector pipeline: Focus on dust settling in horizontal pipes, regularly check for broken filter bags sending fiber debris into ducts

• RCO and RTO catalytic combustion pipeline: Watch for tar and carbon deposits, control exhaust temperature to avoid viscous material polymerization

• Desulfurization and denitrification pipeline: Prevent slurry crystallization and salt deposits caused by flue gas condensation

• Photo-oxygen catalytic exhaust system: Check for sticky organic matter accumulation on the inner wall of front pipelines

What to Do After Locating the Blockage Point

After confirming the blockage position and deposit type, select suitable cleaning measures. Dry dust can be removed by high-pressure air purging or mechanical brushing. Tar and sticky mixed deposits need hot water cleaning or special solvent cleaning. Hardened crystalline materials may require manual cleaning after opening pipe sections. After cleaning, test the airflow and pressure drop again to verify recovery effect.

It is critical to find out the root cause after cleaning. If only clearing the blockage without adjusting gas speed, heat preservation or pre-treatment equipment, pipe clogging will appear again in a short time. The technical team of Zhengzhou Puhua Technology can provide system assessment for exhaust gas and dust removal projects, optimize pipe layout and matching equipment parameters to reduce repeated blockage risks.

Preventive Measures to Reduce Exhaust Pipe Blockage

1. Keep proper gas flow velocity inside pipelines, avoid low-speed areas where dust settles

2. Add heat tracing and insulation for high-humidity flue gas pipelines to reduce condensation

3. Set inspection ports and cleaning openings at easy-to-block positions for routine maintenance

4. Establish regular parameter recording system, track differential pressure trend to discover early blockage signs

5. Configure pre-filter devices to intercept large particles and impurities before gas enters main pipelines

Conclusion

Troubleshooting blockages in exhaust gas treatment equipment pipes relies on systematic judgment combining operating data, external inspection and internal detection. Maintenance teams should not only focus on cleaning existing deposits, but also optimize the whole exhaust treatment system to control the source of pollutants. When users encounter complex pipe blockage problems of dust removal, desulfurization and VOCs treatment equipment, they can consult professional environmental protection equipment suppliers. Zhengzhou Puhua Technology supports customized design of exhaust and dust treatment systems, and provides technical guidance for system operation and maintenance.