Introduction In industrial settings where bulk acid storage is a common necessity, selecting the right lining material for storage tanks is crucial. Even a minor oversight can lead to severe damage, environmental hazards, and significant financial losses. This case study highlights the importance of understanding the specific requirements of your storage solutions.

The Challenge Our customer operates 8-10 bulk acid storage tanks used to store Hydrochloric Acid (HCl). These tanks are constructed with mild steel (MS) and lined with rubber, a standard practice for storing HCl. However, the tanks developed small punctures at the bottom, approximately 1-2 cm in diameter, causing substantial losses and environmental hazards.

Root Cause Analysis Upon investigation, it was discovered that the damage pattern occurred when the storage tanks were idle for extended periods, with HCl not in use. Despite rubber lining being resistant to HCl, further analysis revealed the presence of Ethylene Dichloride (EDC) in the tanks at 5000 PPM. This impurity, which should generally not impact the selection of acid-resistant lining, posed a unique challenge.

The Insight The density of EDC (1.35) compared to HCl (1.1-1.2) resulted in EDC settling at the bottom of the tanks, especially where there was a slight slope. This unexpected deposit led to the punctures and subsequent leakage.

The Solution To address this issue, we implemented an acid-resistant brick lining with a suitable material capable of withstanding the presence of EDC, up to a height of 0.7 meters from the bottom of the tanks. This solution effectively mitigated the problem, preventing further damage and ensuring the safety and integrity of the storage tanks.

Conclusion This case study underscores the critical importance of thoroughly understanding the chemical composition and potential impurities in your storage materials. Selecting the appropriate acid-resistant lining can prevent significant damage, protect the environment, and save costs in the long run. If you’re facing similar challenges, consider consulting with experts to evaluate and optimize your storage solutions.