Main Causes of Pressure Build-up in Tire Pyrolysis Furnaces

Main Causes of Pressure Build-up in Tire Pyrolysis Furnaces

Pressure build-up in pyrolysis furnaces essentially occurs when the rate of gas generation inside the furnace exceeds the rate of gas discharge, or when the gas discharge path is blocked. The specific causes can be categorized as follows:

I. Blockage of Gas Discharge Paths

Condenser System Blockage

Heavy oil and carbon black in pyrolysis gas foul or accumulate on the inner walls of condenser heat exchange tubes, reducing condensation efficiency and causing excessive accumulation of non-condensable gases.

Pipeline and Valve Blockage

Impurities such as carbon black and coke particles enter pipelines with the gas flow, or valves become stuck due to long-term high-temperature operation, resulting in narrowed or completely blocked gas discharge channels.

Venting System Blockage

Venting pipelines become blocked due to corrosion, carbon deposits, or external debris, preventing normal pressure relief during overpressure.

II. Improper Process Operation

Excessively Fast Heating or Uneven Raw Material Distribution

A heating rate exceeding 50℃/h, or uneven distribution of raw materials in the furnace, causes local overheating, generating a large amount of pyrolysis gas in a short time that exceeds the system's processing capacity.

Excessively High Moisture Content in Raw Materials

Moisture in raw materials vaporizes rapidly at high temperatures, producing a large amount of steam that causes a sharp pressure rise inside the furnace.

Delayed Gas Flow Adjustment

Failure to timely adjust the opening of non-condensable gas reuse or venting valves in response to changes in furnace pressure, leading to a mismatch between gas generation and discharge rates.

III. Equipment Malfunctions and Failures

Pressure Relief Device Failure

Safety valves and rupture discs fail to activate at the set pressure due to corrosion, jamming, or lack of regular calibration, preventing timely pressure relief during overpressure.

Cooling System Malfunction

Shutdown of cooling water pumps, loss of cooling water supply, or fan failure causes the condenser to lose cooling capacity, sharply reducing pyrolysis gas condensation efficiency and leading to massive accumulation of non-condensable gases.

Equipment Seal Leakage

Damage to furnace body or pipeline seals allows external air to enter, forming an explosive gas mixture with pyrolysis gas. To contain the leak, venting valves may be partially closed, indirectly causing pressure build-up.

IV. System Design or Maintenance Deficiencies

Undersized Pipeline Diameter

The diameter of gas discharge pipelines is insufficient to handle the maximum gas output, leading to sustained high load and potential pressure build-up.

Lack of Pressure Interlock Protection

No interlock devices are installed to automatically cut off fuel or activate emergency venting during overpressure, preventing automatic intervention when pressure abnormalities occur.

Inadequate Daily Maintenance

Failure to regularly clean carbon deposits and impurities from condensers and pipelines, or to calibrate safety instruments, allows hidden hazards to accumulate over time.