When it comes to chemical storage, the decisions you make today can have a profound impact on your bottom line for years — even decades — to come. While the upfront cost of a storage tank is certainly important, it's just one piece of a much larger financial picture. When calculating the true cost of a chemical storage tank, consider the cost over the useful life of the product — not merely the upfront cost.
Small adjustments in tank material, wall thickness, fitting design, flexible connections, venting, and even gasket selection can make a significant difference in long-term savings by reducing maintenance costs, improving operational efficiency, and extending tank life. Let's explore how these seemingly minor decisions can add up to major cost savings over time.
One of the most critical decisions in tank selection is the material itself. While several options exist — including fiberglass reinforced plastic (FRP), stainless steel, and various types of polyethylene — not all materials deliver the same value over time.
XLPE tanks possess excellent impact resistance, tensile strength, and resistance to fracture that linear polyethylene just can't match. This structural superiority translates directly into cost savings.
Based upon surveys of actual customers over 45 years, high-density crosslinked polyethylene (XLPE) lasts 100-300% longer than linear polyethylene tanks. This can translate into ten-plus additional years of useful tank service, with 15-20 years as the typical useful life of high-density crosslinked polyethylene tanks.
A linear tank's life expectancy is typically 4-6 years. You'll get three times as much life out of a cross-linked polyethylene tank for only a slightly higher initial cost.
XLPE provides the lowest total cost of ownership, from initial purchase through lifetime maintenance. When comparing XLPE to other materials:
Your choice of chemical tank material also dramatically affects ongoing maintenance requirements. XLPE has a lower cost of ownership, due to the low amount of required maintenance compared to FRP storage tanks.
Unlike chemical storage tanks made of other materials, crosslinked polyethylene tanks require limited routine maintenance. Steel tanks require external preventive care such as painting and internal inspection to determine weld integrity. Fiberglass also poses its own issues, such as multiple layer construction and the sensitivity toward micro-cracking.
Not only do XLPE chemical storage tanks have lower upfront costs and minimal maintenance requirements, they also have no need for painting or coating (UV additives can be integrated throughout the tank wall).
Related: Spending Less on a Chemical Storage Tank Could Cost You
Wall thickness isn't a one-size-fits-all specification—it must be calculated based on the specific chemical being stored and the tank's geometry.
The necessary thickness of your chemical storage tank's walls will depend on the chemical being stored and the tank's geometry or size. Multiple factors influence this calculation.
The chemical itself, and its operating temperature, determine a tank's specific gravity rating (SPG). Chemicals that are dense and warm have a higher specific gravity than lighter, cooler chemicals. Your tank needs to be rated for the correct specific gravity, or it could fail prematurely.
As fluid specific gravity increases, a storage system will require a thicker wall to withstand additional stress from the increased temperature and weight.
Tank shape and size also play a crucial role in determining appropriate wall thickness. A six-foot diameter tank holding the same chemical and volume as a twelve-foot diameter tank will have less surface area on the bottom sidewall which means it will require thicker walls to compensate for the increase in hoop stress calculated for that tank design.
Tank walls can range from .20 inches thick to 2 inches thick or thicker, depending on size, dimensions, and where the measurements are taken.
Tanks that are rated too low can suffer from mechanical stress and early failure. This underscores why proper engineering at the design phase is so critical to long-term cost management.
One of the most significant innovations in tank design is Poly Processing’s Integrally Molded Flanged Outlet® (IMFO®) Tank. The IMFO is a homogenous flange system that is molded as part of the tank while the tank is being manufactured, making the flange a stress-free part of the tank. The flange is created from the same material as the tank — it's not an insert added during or post-production.
This design feature delivers multiple cost benefits. Besides giving you full tank discharge, enhanced long term performance, and very high static head pressure, any required maintenance to the fitting, gaskets, or bolts is simple and hassle-free.
The ability to fully discharge the tank has direct operational cost implications, as well. Consider sodium hypochlorite storage. When sodium hypochlorite settles over time, it makes sludge, which degrades the chemical in the tank, so you need more of the chemical to do the job. This results in the need to order more chemical, which is expensive.
With Poly Processing's IMFO full discharge fitting, the tank can be emptied completely. This results in a tank that does not contain sludge, leading to lower operating costs and higher efficiency all around.
For particularly aggressive chemicals, the OR-1000 antioxidant system provides an additional protective barrier. Poly Processing's exclusive OR-1000 system was specifically designed to address the aggressive oxidation effects of sodium hypochlorite, sulfuric acid, and hydrochloric acid by adding an additional resin system between the XLPE and the chemical. It is designed to maximize the useful life of storage tanks in oxidizing environments.
This system increases the life of a crosslinked polyethylene tank giving the end user a greater cost-effective solution.
Poly Processing’s tank manufacturing method significantly impacts long-term reliability. Because of its seamless one-piece molded construction, polyethylene storage tanks lack the seams where leaks tend to develop.
In contrast, fiberglass tanks are filament-wound or hand laid up, creating seams that become vulnerable weak points for leaks. Manufacturers add tops and bottoms post-production, with seams that further increase leak risks.
XLPE tank material is also resistant to corrosion, which means maintenance is practically eliminated throughout the increased useful life of the tank.
The proper selection of gaskets, bolts, and fittings is crucial for long-term tank performance and safety.
A chemical storage tank's gaskets act as a mechanical seal with a particular fitting to prevent leaks or spills.
It is very important to make sure the gaskets and bolts used on your storage tanks are in compliance with what is needed to protect your tank fittings from corrosion caused by reactive chemicals.
Additionally, the chemical you are storing will dictate the types of gaskets and fittings used on the tank system. Thinking ahead in this way makes for a longer useful tank life.
With its streamlined one-piece design, the B.O.S.S. (Bolted One-Piece Sure Seal) Fitting® reduces the seal point to a single gasket to greatly reduce chances of leakage.
The design provides several key advantages. Instead of multiple sealing surfaces like a standard flange fitting, reducing sealing surfaces to one point means reducing opportunities for leaks and creating a very tight seal. Bolts are welded to a standard metallic ring, which gives a more robust fitting than any composite fitting on the market. It reduces stress on the fitting and helps prevent leaking over time, making it many times stronger than standard plastic fittings.
Many tank manufacturers certify their tanks alone, but fittings and gaskets are equally important. Poly Processing is the only chemical storage tank manufacturer to take a full-system approach to NSF approval. We supply an entire tank system, including fittings, gaskets and specific tank colors, that are certified for NSF/ANSI 61.
Secondary containment is often required, but the method you choose can significantly impact both upfront and ongoing costs.
Traditionally, chemical containment systems are composed of large, concrete basins that surround a primary storage tank. While this solution adds a layer of protection, it also adds costs, square footage, and high-maintenance complications.
If a spill occurs in a concrete secondary containment, the spilled chemical is usually unrecoverable because of contamination. You'll need to clean out the containment area, replace the lost product, and possibly recoat the concrete basin.
Related: Evaluating Your Containment Costs: SAFE-Tanks vs Concrete Secondary Containment
The SAFE-Tank offers a more cost-effective alternative. Altogether, the SAFE-Tank system can be up to 90% more cost effective than traditional concrete containment structures.
Benefits include:
A manufacturer's warranty can be an indicator of product quality and expected lifespan.
Fiberglass storage tanks typically offer a limited one-year warranty period. The industry standard for polyethylene chemical storage tanks is three years unless you pay for an extended warranty.
In contrast, Poly Processing offers more robust warranty coverage, with XLPE chemical tanks having a five-year full warranty, with a life expectancy of 15-20+ years in most cases.
The decisions you make when selecting a chemical storage tank—from material type to wall thickness, from fitting design to gasket selection—will echo through your facility's operations for years to come. While it may be tempting to focus solely on upfront costs, the true measure of value lies in total cost of ownership.
In most cases cross-linked polyethylene offers longer useful life in the same application as linear polyethylene. While the two plastics are both chemically inert materials, because XLPE has a significantly longer life and less financial impact in case of failure, the total useful life of cross-linked polyethylene is significantly better for your bottom line.
By investing in properly engineered tanks with appropriate wall thickness, quality fittings with compatible gaskets, and innovative design features like the IMFO system and OR-1000 antioxidant barrier, you're investing in:
The small changes you make in tank selection today will continue to pay dividends throughout the entire life of your storage system. Choose wisely, engineer properly, and reap the benefits of a well-designed chemical storage solution for decades to come.
Ready to optimize your chemical storage for long-term cost savings? Contact a chemical storage expert to discuss how proper tank selection can benefit your facility's bottom line.