Best Practices For Sulfuric Acid Storage Tank Design

 Sulfuric acid can be a tricky chemical to store. Used in a wide variety of industrial applications, sulfuric acid is heavy, can create toxic or flammable gas, and can burn the skin. A smart storage solution for sulfuric acid should start with a well-thought-out tank design - not of just the tank material but the entire storage system and all components.

Thinking through the entire storage tank system design up front will help you protect your employees, the environment, and your investment. Read on for our recommendations on the right material, configuration, and standards for safe sulfuric acid storage.

Best Tank Material For Sulfuric Acid Storage

At Poly Processing, we’ve developed proprietary polyethylene that makes for the ideal storage material for sulfuric acid. Crosslinked polyethylene (XLPE) tanks provide unmatched load tolerance that can more than handle the chemical’s heavyweight.

XLPE’s molecular bonding, combined with a thick tank wall, provides necessary structural strength. This is especially critical in the bottom third of the tank, where the highest hoop stress levels are concentrated.

Tank Configuration For Storing Sulfuric Acid

Secondary containment is recommended when storing sulfuric acid. If your storage tank leaks, secondary containment can capture the leak before it causes a risk to your staff or facility.

If you don’t already have a secondary containment structure in place, our SAFE-Tank® solution is a smart choice. A SAFE-Tank is a tank-within-a-tank system that has secondary containment built-in. It is a space and cost-efficient method that greatly reduces the possibility of sulfuric acid leaking into the surrounding environment or coming into contact with water (which can result in a toxic sulfuric acid aerosol or a potential explosion).

SAFE-Tank® systems can also be built with OR-1000™, a tank system which provides an additional layer of protection against the chemical’s aggressive oxidation.

Sulfuric Acid Storage Tank Size Recommendations

Sulfuric acid is a very heavy chemical which puts a lot of stress on a storage tank. Therefore, only a set amount can be safely stored in a single tank. If you’re storing sulfuric acid concentrations of 93% or greater, the maximum size tank you can use without an engineering review is 4,000 gallons. If you need larger storage, we recommend splitting the chemical into multiple smaller tanks. If one tank begins to leak or if there is an accident with a tank, you will still have other tanks that are intact.

This is a common solution in the mining industry, especially in smaller mines. They often use four or five 12,000-gallon tanks running back-to-back. The tanks are connected to each other via a piping system and they turn the valves on and off as needed. From a safety perspective, each tank is separated from the others, so that if one tank fails or is damaged, the spill is smaller and most of the chemical supply is preserved.

NSF-61 Certifications For Sulfuric Acid Storage

Poly Processing tanks are certified to NSF/ANSI-61 Standards, up to a 98% concentration of sulfuric acid. Poly Processing is the only company with a complete chemical storage tank system certified to NSF/ANSI Standard 61.  All Poly Processing, OR-1000™ chemical storage tank systems and associated fittings adhere to these stringent specifications.

Sulfuric Acid Storage You Can Depend On

Some storage tank manufacturers are willing to provide 12,000-gallon linear sulfuric acid tanks. Other companies will install large fiberglass tanks, because the customer may want to hold a railcar of sulfuric acid. We have helped customers who tried fiberglass sulfuric acid tanks that failed. They lost 40,000 gallons of sulfuric acid in a short moment. They learned a costly lesson and made the switch to smaller crosslinked polyethylene tanks.

Under certain circumstances, you may be able to safely use larger tanks, but you should talk with our engineers before making any commitments. We can help you think through your plans for sulfuric acid storage and design a system that meets your needs.

Poly Processing has developed technologies to ensure safe storage of sulfuric acid. We’ve learned over the last 30 years what works to keep our customers safe.

Need a custom storage solution for sulfuric acid? Talk to a chemical storage tank specialist today!

For more information, please download our Sulfuric Acid Storage Guide.