The Importance of Sulfur Melting in Sulfuric Acid Production

Sulfuric acid production involves a complex process, with sulfur melting being a critical step. This phase is essential not only for the efficiency of sulfuric acid production but also for ensuring safety throughout the facility. Various abnormal situations can arise at the sulfur melting section during sulfuric acid production, impacting both safety and efficiency. This article discusses common issues encountered during this phase, their causes, and simple solutions to ensure a smooth production process.

1. Excessive Ash Content in Liquid Sulfur

Reason:

Excessive ash content may result from improper operation during the pre-coating process, filter leaf corrosion, or inadequate sealing of filter elements. High ash levels can lead to operational inefficiencies and affect the V2O5 catalyst where pressure drop may increase.

Solution:

• Reapply the pre-coating as necessary.
• Replace any damaged filter meshes.
• Check and repair the seals on filter elements to ensure effective filtration before starting sulfur melting during sulfuric acid production.

2. Excessive Acidity in Liquid Sulfur

Reason:

High acidity often comes from incoming sulfur with high acid content, insufficient alkali for neutralization, or delays in adjusting alkali amounts. Excess acidity can corrode equipment and affect downstream processes.

Solution:

• Monitor the acidity of the incoming sulfur continuously.
• Promptly adjust the alkali quantity to neutralize any excess acidity to maintain optimal levels.

3. Overflow in Sulfur Melting Tank

Reason:

Blockages in the overflow pipe may cause overflow due to debris or excessive feeding. This can create safety hazards and lead to sulfur losses.

Solution:

• Regularly check and clean the overflow pipe to prevent blockages.
• Control the feeding to ensure they stay within safe limits.

4. Decreased Sulfur Melting Capacity

Reason:

Decreased melting capacity may be caused by scaling in the steam coil, low steam pressure or temperature, or high moisture content in raw sulfur. These factors can significantly affect production rates.

Solution:

• Clean the coil regularly to prevent scaling and ensure efficient heat transfer.
• Check the efficiency of the steam system for optimal performance.
• Control the moisture content in the raw sulfur to maintain quality.

5. Excessive Steam Emission from the Sulfur Tank

Reason:

Excessive steam emissions can result from open firefighting steam, high moisture content in raw sulfur, or leaks in the steam coil. This can lead to energy inefficiencies and increased operational costs.

Solution:

• Ensure that firefighting systems are closed when not in use to minimize unnecessary steam release.
• Manage the moisture content of raw materials to prevent excess steam generation.
• Repair any leaks in the heating coil promptly to maintain efficiency.

6. Fire in the Sulfur Melting Tank or Filtering Tank

Reason:

Fires can occur due to high temperatures in melting or insulation steam, the presence of flammable organic materials, or auto-ignition of FeS. Such incidents pose significant safety risks.

Solution:

• Lower the temperature of the steam used in sulfur melting to reduce fire risk.
• Monitor raw materials for flammable substances and ensure they are properly managed.
• Regular inspections should be conducted to prevent ignition of FeS accumulation.

7. Filtering Pump Unable to Build Pressure

Reason:

Pump failures can result from faults in the pump components, blockages at the suction pipe, or obstructions in the discharge pipe. This can lead to reduced flow rates and operational disruptions.

Solution:

• Perform routine maintenance on pumps to ensure reliable performance.
• Clear any blockages in the suction and discharge pipes promptly.

8. Fire in the Sulfur Filters

Reason:

Fires in sulfur filters are often associated with high insulation steam temperatures or flammable materials in raw sulfur.

Solution:

• Reduce insulation steam temperatures to mitigate fire risks during sulfur melting.
• Increase monitoring of the composition of raw materials to identify potential hazards.

9. Filter Leaf Cannot Be Removed

Reason:

Hydraulic system malfunctions, extended filtration cycles, or low temperatures could cause this problem, leading to inefficiencies in the filtration process.

Solution:

• Inspect and repair the hydraulic system as needed.
• Shorten filtration cycles to prevent excessive build-up.

10. Sulfur Appearing in Steam Condensate Drainage

Reason:

Sulfur in condensate may indicate leaks in the jacketed steam pipe or undetected holes in the heating coil. This can lead to product losses and contamination issues.

Solution:

• Regularly inspect the insulation piping for leaks.
• Address any holes in the coil promptly to maintain product integrity.

11. No Flow in the Liquid Pure Sulfur Pipeline

Reason:

Flow issues may arise from pump malfunctions, blockages in the discharge pipe, or flow meter problems, which can hinder production efficiency.

Solution:

• Inspect and repair the pump and piping systems to ensure proper flow.
• Ensure that flow meters are functioning properly to provide accurate measurements.

12. Sulfur Leak from Flange Connections in Liquid Sulfur Pipeline

Reason:

Flange leaks can result from loose bolts, defective gaskets, or expansion leakage when melting solid sulfur. This can lead to material losses and safety hazards.

Solution:

• Regularly check flange connections for tightness.
• Replace any defective gaskets as needed to prevent leaks.

Conclusion

By proactively addressing common issues in the process, facilities can enhance safety, improve efficiency, and ensure consistent production of sulfuric acid. Regular maintenance, monitoring, and adherence to best practices are essential for minimizing risks and maintaining optimal operations.

Get a challenge? Contact us for a solution

You may be interested in Sulphur (sulphuric-acid.com)