Why Plastic Water Tanks Won’t Work For Chemical Storage

Storing chemicals and storing water are two very different propositions. While you may save some money up front by using a water tank to store chemicals, in the long run this decision may end up costing you more than you think. There are a few critical reasons why you shouldn’t use water tanks for chemical storage.

Proper Specific Gravity Rating For The Chemical

Water tanks are designed with a specific gravity rating that is made to handle the weight of water. Generally speaking, tanks to store water are built to handle a specific gravity rating of between 1.0 and 1.35. Chemicals with a fluid specific gravity outside of this range require a tank built to handle that type of chemical. 

For example, when we build tanks to hold a chemical like hydrofluoric acid, we use a specific gravity rating of 1.9 with cross-linked polyethylene resin, instead of the standard linear polyethylene used to manufacture many water tanks. If you use a tank that is not rated for the chemical, it can break down, leak, or even fail catastrophically, requiring costly maintenance of equipment and placing employees in danger.

Water Tanks Are Not NSF Certified For Chemicals

Some companies in the industry sell tanks that are NSF certified for potable water, leading customers to believe they are also certified for chemical storage. This is not true, as NSF certification is based on individual chemicals. The tests conducted by NSF are designed for either water or individual chemicals based on the leaching of foreign materials into them and other testing. Just because a tank is NSF certified for water does not make it suitable for chemical storage. 

Water tanks also do not require any specialized interior surface, such as OR-1000, that chemical storage tanks often require. Chemicals such as hydrochloric acid or sulfuric acid can easily damage a water tank’s walls because they are not constructed for the weight and oxidation of the chemical.

Fittings and Gaskets Must Comply With The Chemical

Fittings and gaskets on your storage tanks are critical. If these tank components are not designed and installed to the specifications required to handle chemicals, it puts the tank at risk of leaking. In addition, NSF has strict requirements for the material of fittings and gaskets allowed.

With water being a stable substance compared to other chemicals, the gaskets and fittings that you will find on water tanks may not be able to withstand corrosion or protect against leaks as well as our IMFO® or our B.O.S.S. Fittings® which are specifically engineered to do.

A Better Chemical Storage Solution

It's always best to start with the chemical that is going to be stored and design the tank around that chemical.

At Poly Processing, this is the approach that we take every time. We believe in providing specific solutions based on the particular chemical. This ensures that our customers have a long lasting, safe and reliable solution to their storage needs.  

To find the right chemical storage tank for your system, we invite you to learn more about our most popularly stored chemicals.