Zaklady Azotawe, Pulawy, Poland: Acid Tank Lining

Zaklady Azotawe in Poland had a bulk storage tank for the containment of sulphuric acid at various concentrations. The carbon steel tank was of standard vertical cylindrical design, 5m high and 4.5cm diameter. The tank had been previously lined with a traditional vulcanised rubber system, which needed to be replaced in the lower half of the vessel. The company had installed a new rubber lining but it immediately failed so we were called to upon to identify the cause and make suitable recommendations. We found that although the tank had been thoroughly washed prior to the start of the work, small amounts of H2SO4 in crystalline form had remained on the upper areas of the existing tank lining. This had corroded the rubber lining before it had become resistant to the acid.

Challenges

  • Storage temperatures ranged from 25-85% and 35-50°C.

Our Solution

Our recommendation was to remove all the rubber completely and apply a liquid resin lining system. We were able to find the most suitable material for this application, which was a high tech modified acid resistant epoxy resin system. 

Results

Although the materials for the project were quite expensive, when comparing the cost of applying a new rubber lining or changing the technology completely, our solution proved to be 45% cheaper. The lining was applied at the beginning of 1997 and the tank has been in constant use since then with a fully operational lining.