Whether you’re an engineer writing a spec for a chemical storage system, or an end-user who is looking for the best way to store corrosive chemicals, there are multiple factors that go into creating a safe storage system. Cost might be your first consideration, but there is more to consider than the initial price of the tank, its fittings and accessories, delivery, and installation.
It’s important to consider the durability and longevity of the tank system when you’re storing corrosive chemicals. In fact, every good tank design starts by considering the chemical you’re storing. Everything else flows out of that. Leaks and degradation can be costly to repair—and even more costly when a tank system has to be replaced because it wasn’t engineered to store your corrosive materials.
Let’s take a look at the nature of corrosive chemicals and the chemical storage industry’s best tank options to help you make the right storage tank decision.
What Chemicals Are Corrosive?
A corrosive chemical is one that will damage or destroy another substance upon contact. The higher the concentration, the more corrosive it is. It can cause chemical burns to live tissue, and the chemical fumes can cause eye and lung irritation or damage. Both acids and bases can be corrosive.
Some commonly stored corrosive chemicals include:
Many of these chemicals can corrode metal, especially at higher temperatures. When metals corrode because of these substances, they give off a hydrogen gas, which is flammable.
If you are storing your chemicals in a plastic tank, there is no metal to corrode and you are protected from these hazardous fumes. That is why polyethylene is the preferable tank material for storing these types of chemicals.
Not All Polyethylene Tanks Are Created Equal
Polyethylene is a durable plastic that’s available in medium-density, high-density (HDPE) and high-density cross-linked (XLPE) forms. Medium- and high-density polyethylenes are usually linear, which means that the polymers of the plastic are joined in a twisted formation like rope fibers, rather than knotted in nature.
XLPE is created in a way that the very molecules of the plastic are bonded and linked, creating a superior product that has much greater impact and tensile strength of linear polyethylene. Imagine a chain-link fence where the metal is actually linked together. The chemical resistance, heat resistance, and dimensional stability are unparalleled.
Crosslinked polyethylene has covalent bonds that connect its polymer chains. These bonds tie the polymers together and lengthen the polymer chains, giving the polyethylene stronger resistance to corrosive materials. The molecular structure provides superior stress cracking resistance, improved toughness and much greater useful life compared to linear polyethylene.
Extend Your Tank’s Resistance to Corrosion
To extend the longevity of your cross-linked polyethylene tank, you can store corrosive chemicals in an XLPE tank with an anti-oxidant barrier system. The technology behind Poly Processing’s OR-1000™ takes the guesswork out of choosing the right storage tank system for corrosive chemicals.
The OR-1000 is a barrier resin made of medium density polyethylene, but what makes it special is the 400 percent more antioxidant additives in that resin. OR-1000 is added to your chemical tank during the rotomolding process, which creates a seamless bond between the barrier resin and the XLPE polyethylene. The result is a stronger, more durable tank system that doesn’t have the risks and maintenance costs of an FRP tank or a mass-produced polyethylene tank with a potentially faulty lining.
This unique combination of polyethylenes creates an ideal containment for even the most corrosive chemicals:
- XLPE gives you the strength from catastrophic failure and corrosive chemical getting out.
- OR-1000 gives you optional additive oxidation resistance over time.