Case Study

Resolving Baghouse Issues at a Steel Plant in Oklahoma

Background

A steel plant in Oklahoma was experiencing ongoing issues with its reverse air baghouse system. The primary concern involved filter bags dislodging from the tubesheet, leading to bypass problems that significantly affected system performance. The plant sought a solution that would not require a complete replacement of the tubesheet, prompting them to reach out to us for assistance.

The Challenge

The plant’s reverse air baghouse was compromised due to filter bags consistently popping off the tubesheet. This problem caused unfiltered air to bypass the bags, reducing the efficiency of the filtration system. The plant had been using 10 oz fiberglass bags with fiberglass cuffs, but this setup wasn’t providing the necessary seal, especially given the inconsistencies in tubesheet hole sizes.

Investigation

Upon arriving onsite, Menardi’s team performed a detailed inspection of the baghouse. Using precision calipers, we measured the tubesheet holes across multiple compartments and found significant inconsistencies in the sizes of the holes. This lack of uniformity contributed directly to the issue of filter bags not seating securely in the tubesheet.

We also inspected the hopper below the tubesheet and discovered that it was nearly full, with dust levels about a foot below the tubesheet. This accumulation of dust, combined with the high airflow drawn in by the fan, was creating a sandblasting effect within the hopper, which was damaging the snap bands on the filter bags.

Solution

To address the tubesheet issue without requiring a costly replacement, we recommended switching from fiberglass cuffs to more flexible aramid cuffs. In addition to this, we offered our “super-bead” DBSR, a deeper grooved DBSR, which allowed for more of a channel to fit the inconsistent holes found in the tubesheet. The other suppliers had used lighter gauge steel bands (.015” thick), typically designed for smaller diameter pulse jet filters (4.5-6”). These bands were “popping out” of the larger tubesheet holes. By switching to thicker .032” steel bands, we provided a firmer, more defined snap fit that, combined with the deeper groove DBSR, accommodated the tubesheet’s inconsistencies more effectively.

Aramid material has a greater degree of flexibility, which allowed for a secure seal even on the uneven tubesheet holes. Additionally, the aramid felt provided a better gasket effect and more cushion than woven fiberglass, offering greater abrasion resistance against particulate hitting the bottoms of the bags. This change immediately solved the problem of the filter bags popping off the tubesheet.

In addition to this, we identified and addressed the hopper dust accumulation issue by alerting the plant team to a malfunction in their rotor airlock. After the plant repaired the rotor airlock, Menardi revisited the site to ensure the baghouse system was functioning correctly and to confirm no further damage to the snap bands.

Results

Following the installation of the new aramid cuffs in late 2018, the plant experienced trouble-free operation with consistent, optimal performance. The tailored solution provided by Menardi not only resolved the immediate issue of the filter bags dislodging but also prevented future system damage by addressing the dust accumulation problem. This long-term fix has ensured the steel plant’s reverse air baghouse system continues to operate efficiently.

Conclusion

This case illustrates the importance of comprehensive inspections and customized solutions in resolving complex filtration challenges. Menardi’s expertise in material selection and system troubleshooting led to a lasting fix for the steel plant in Oklahoma, ensuring improved performance and reduced maintenance needs moving forward. At Menardi, we are committed to providing practical, effective solutions that meet our customers’ operational needs.