Sauereisen Innovatively Restores Process Tank in MN

Source: Sauereisen, Inc.

A major chemical plant in St. Paul, MN, faced a significant challenge to restore its steel alkylate tank in 2005. The 48-foot diameter tank functions as a key process vessel used in a complex that includes HF and sulfuric acid plants.

A pre-existing, veiled glass lining system had developed severe burn holes. Eventually, metal corrosion occurred on the sidewalls extending seven feet high. The aggressive mix of chemistry and temperature had combined to compromise the tank. The owners sought a protective system combining low permeability and high temperature resistance since continuous temperatures of 140oF repeatedly spiked to almost 300oF during heat of reaction excursions.

Initially, the targeted means of repair centered on a brick lining with appropriate mortar. Unfortunately, this proposal proved to be prohibitive due to the required downtime of masonry construction and associated cost. The last thing anybody wanted was a prolonged construction project.

Sauereisen Inc., of Pittsburgh, PA, provided a more novel material recommendation that suited the demanding requirements. Sauereisen's approach was to spray-apply its vinylester-based, fiber reinforced lining system.

The restoration started with surface preparation that included patching and coverage of exposed weld seams with Sauereisen Universal Block Filler. After priming with a vinylester primer, the next step included a spray application of FibreLine No. 440 at a wet film thickness of 40 mils. The final topcoat included 10 mils of Sauereisen's VEGlaze No. 472.

Fiber-reinforcement within Sauereisen's lining provided excellent durability. Compared to matte lay-up systems, and the previously mentioned brick alternative, spray installation of FibreLine proceeded at a much more rapid pace as performed by VE Gray and Son of St. Paul, MN. Sauereisen's field representative, Ellis Steiner of Cornerstone Sales & Marketing in Racine, WI, provided additional consultation.

All together, the project was completed satisfactorily with the tank attaining renewed longevity, in quick-turnaround fashion, at an affordable investment.

SOURCE: Sauereisen, Inc.