Wastewater Systems and Fiberglass

Wastewater systems will vary in scale and complexity depending on the application; common wastewater systems are designed to meet the needs of housing developments, municipalities, resorts, public parks, sanitary stations, rural development, recreation areas, and schools—just to name a few. One of the most common problems related to wastewater systems is their susceptibility to corrosion. This issue is of particular concern for facility managers, planners and engineers who must adhere to stringent Federal, State and local regulations. Fiberglass provides stability and assurance to those who need solutions; custom-fabricated fiberglass products are ideal for wastewater systems—when designed properly, to specification, they are structurally sound, watertight, corrosion and abrasion resistant, and most importantly—a cost effective option.

Within wastewater treatment systems, regardless of whether they have been designed for treating 1,000,000 gallons per day or more, or for small commercial use, hydrogen sulfide and sulfuric acid may potentially cause degradation to infrastructure and/or lead to corrosion issues. Anaerobic conditions provide environments that feed acid generating microbes. Fiberglass that has been designed and fabricated with a corrosion barrier is an ideal materials solution in many wastewater applications, especially where anaerobic conditions are persistent.

Fiberglass brings versatility to the table—among much else including light-weight, high strength-to-weight ratio, it can also be designed to meet vacuum specifications—an important component in some wastewater applications. Fiberglass applications in the wastewater or water purification industry include, but are not limited to, chemical water treatment, industrial waste water treatment, lime-soda treatment, chlorine, disinfection, clarification, demineralization, oil demulsification, metal precipitation, odor, control, bioaugmentation, and the processing/handling/storage of many chemical precipitants, coagulants, flocculants, and defoamers.

Corrosion is a systemic issue that plagues just about every aspect of our life. According to one recent study released by NACE and CC technologies, the US production and manufacturing sector alone reports and estimated $17.6 billion annually in damages—this includes major industries such as agriculture, petroleum, power generation, and pulp and paper. In particular, the water and wastewater sector accounts for approximately $36 billion or 14% of the direct cost of corrosion in the U.S. alone, a staggering $276 billion dollars annually.

According to NACE International, “Both public and private water and wastewater agencies throughout the United States have infrastructure assets ranging in value, from millions to billions of dollars. Assets include, dams, aqueducts, tunnels, transmission/collection pipelines, water and wastewater treatment plants, pumping plants, distribution pipelines and storage.” Research has shown that fiberglass is a sound option for replacing many traditional materials, specifically in water related applications, materials such as concrete, steel alloys, cast iron, ductile iron, brass, copper and or any other material that cannot withstand corrosive attack.

Think of the possibilities; within the wastewater industry there are many ideal jobs for fiberglass—projects where functionality is critical and where long life cycles can have huge returns. Custom fiberglass materials could be used for dosing tanks, surge tanks, settling tanks and other accessories for tank systems including baffle walls, railings, ladders, decking, and fencing. In some systems where chemical applications are necessary batching stations have been designed using fiberglass for both storage, containment and general infrastructure. When it comes down to it, more than anything else, fiberglass can provide effective corrosion systems that have the potential to reduce plant downtime and maximize output.

Sulfuric Acid Storage

Custom fiberglass, with its low maintenance, high performance, heat tolerance, and corrosion resistance is a go-to material in many industries for a multitude of applications.  Sure, ‘custom fiberglass’ sounds expensive. The reality of any situation is always more subtle. When considering the entire range of benefits over time, high-quality custom fiberglass that can be formulated to withstand a variety of acids, bases, chlorides, solvents, and oxidizers and outlast other popular materials of construction such as high-priced nickel alloys is a very cost-effective material.

Fiberglass materials formulated from high quality epoxy vinyl ester resins will outperform stainless steel in chemically aggressive environments including Sulfuric Acid.  For example, in dilute form sulfuric acid is known to be extremely corrosive to carbon steel, yet properly formulated fiberglass can provide corrosion resistance.

With respect to operating environment (i.e. concentration, presence of water vapor, pressure, temperature etc.) many design consideration will need to be addressed. For example, while fiberglass is an exceptional material for many acids, concentrations greater than 75% sulfuric acid may not be suitable for all fiberglass materials—sulfuric acid at these concentrations and greater has an affinity for water—a relationship that has been shown to dehydrate or compromise some fiberglass formulations.  Situations involving high concentrations of sulfuric acid and the presence of water must be carefully analyzed.  Similarly, special attention should be provided where situations involve the diluting of acids.

Per contra, diluted sulfuric acid is very aggressive toward cast iron or steel tanks, but can be stored and handled very well in FRP composite equipment. As a general rule of thumb, FRP composite equipment is best suited for concentrations of 70% sulfuric acid and below. At 75% sulfuric acid, the maximum temperature allowed with vinyl ester resins is 100° to 120°F. As the concentration decreases, the allowable temperature limits increase.

Each job will require an understanding of the design elements that underpin a properly operating system. Although there will be unique challenges inherent to any job—a preferred type of FRP composite vessel for storing sulfuric acid is a non-insulated, vertical, above ground tank. Even underground tanks, with the ground acting as an insulator, may have excessive storage temperatures and additional considerations.

Literature such as Myers, Kytomaa and Smith (2007) described fiberglass materials, as well as, other materials of construction (e.g. steel alloys) as being susceptible to Environmental Stress Corrosion Cracking (ESCC) from exposure to acids. This type of literature is useful in many respects, for example, it provides a ‘lessoned learned’ understanding through case studies of how improperly formulated fiberglass resin matrixes and poorly designed fiberglass materials can lead to unintended results.

To be certain, fiberglass isn’t a panacea, and we understand its limitations and thresholds. When you leverage our design expertise, you’ll gain satisfaction knowing that your materials are optimized for performance. Intellectual or scholarly works also press the importance of improving our understanding of complex relationships—a necessity in operating systems combing a wide range design elements and operating conditions.

For fiberglass products to perform properly in the field, it takes more than just quality manufacturing. Excellent performance requires a high level of engineering and design skills coupled with project related expertise –the kind of expertise that only comes from years of experience. Beetles’ engineers have the experience, the skills, and the knowledge to help you with virtually any project related to fiberglass FRP applications.

Myers, T. J., Kytömaa, H. K., & Smith, T. R. (2007). Environmental stress-corrosion cracking of fiberglass: Lessons learned from failures in the chemical industry. Journal of hazardous materials, 142(3), 695-704.

The Cost of Corrosion

cost of corrosionThe effects of corrosion can be seen in industries across the globe. Every year the costs to repair, maintain, and replace equipment and infrastructure damaged by corrosion increase. In a 2009 study published by the World Corrosion Organization it was estimated that corrosion costs, worldwide, exceed 1.8 trillion dollars 1.

In another study conducted from 1999 to 2001 by CC Technologies Laboratories, Inc with support from the Federal Highway Administration (FHWA) and the National Association of Civil Engineers (NACE), it was revealed that the annual estimated direct cost of corrosion in the US was $276 billion dollars or approximately 3% of the nation’s Gross Domestic Product (GDP)2.

The hefty price tag of corrosion has led many, both domestically and internationally, to seek cost effective corrosion solutions. Luckily fiber reinforced polymers (FRP) offer a material solution that is cost effective for many industries and applications. Because of the corrosion resistant nature of FRP, they offer a short and long-term cost solution.

Specifically, FRP is ideal for corrosion control in the Chemical Processing Industry. The specific difficulties associate with transporting, handling, storing, and manufacturing corrosive chemicals are best addressed with FRP. The long life cycles, high strength-to-weight ratio, dimensional stability, and design flexibility that FRP offers has made it a successful building material in the Chemical Processing Industry for decades.

To learn more about the growing role of FRP in the fight against corrosion, download our free ebook Chemical Processing eBook: FRP Applications, Opportunities, and Solutions.

Chemical Processing eBook

corrosion resistanceWe are very happy to share with you the newest free ebook from Beetle Plastics Chemical Processing eBook: FRP Applications, Opportunities, and Solutions.

In this eBook we cover:

  • What are fiber reinforced polymers (FRP)
  • The corrosion resistance offered by FRP
  • Applications of FRP
  • Engineering services
  • Examples for FRP applications

It’s important to understand the costs of corrosion and why FRP is a preferred solution, because corrosion is a costly problem that affects a wide range of industries and applications.

So download our free ebook Chemical Processing eBook: FRP Applications, Opportunities, and Solutions to learn more about FRP and its role in battling the costs of corrosion.

FRP vs Aluminum: A Snapshot Comparison of Two Materials

frp vs aluminumFRP and Fiberglass

Fiberglass is ubiquitous in a wide range of industries from pulp and paper, wastewater, desalination, and power generation to mining and mineral extraction, marine, petrochemical and chemical processing. There are significant differences with respect to mechanical properties when comparing fiberglass or fiber reinforced polymers (FRP) with metals such as steel or aluminum. Fiberglass is anisotropic, that is, they posses mechanical properties only in the direction of the applied load. In other words, their best mechanical properties are in the direction of the fiber placement. Conversely, steel and aluminum are isotropic, giving them uniform properties in all directions, independent of the applied load.

Fiberglass has exceptional inherent dimensional stability potential due to its unique formulations. Because composites are customizable, they can be designed to maximize the benefits of structural properties. Furthermore, fiberglass materials are often selected by engineers for applications requiring stringent dimensional stability under a variety of extreme conditions. Good dimensional stability or structure, and other properties such as lightweight, strength, toughness, damage tolerance, fatigue and fracture resistance, notch sensitivity, and general durability, make fiberglass desirable for many applications. Moreover, the inherent corrosion resistant characteristic of fiberglass makes it a cost-­‐effective, strong, lightweight solution for corrosion resistant equipment applications in a multitude of industries including chemical processing, wastewater management, and oil and gas.

When comparing strength of materials of equivalent thicknesses and sizes, fiberglass will weigh one seventh as much as steel and half as much as aluminum. There are other very distinct advantages to having specific strength. For example, lightweight properties are important when considering the cost and ease of installation, especially for pipe and tank. FRP has another inherent edge over other products when equipment must be mounted on uneven services, existing structures, such as scrubbers, and on mezzanines or rooftops. Having lightweight properties also works well for specialty applications such as tank trailers.


Aluminum is an abundant element in the Earth’s crust that is widely used throughout the world in a broad range of applications, almost always as an alloy for construction purposes. Its unique combination of properties makes aluminum one of the most versatile engineering and construction materials. Aluminum is refined through the Bayer Process from aluminum ore or bauxite and once refined can be easily formed, machined and cast.

Some key properties include lightweight (about 1/3 mass, of equivalent volumes of steel, copper), excellent thermal and electrical conductivity, highly reflective to radiant energy, highly corrosion resistant to air and water (including sea water), and it’s highly workable into almost any structural shape. Corrosion resistance is a crucial property that can’t be overlooked; when aluminum is exposed to atmospheric conditions a thin oxide layer forms and protects the metal from further oxidation—this makes aluminum attractive as long-­‐term viable solution for many applications. This coating or layer provides protection and allows aluminum to often be used without any type of coating or paint.

One of the most important components of aluminum’s corrosion resistance is that the aluminum oxide layer formed is impermeable, adheres well to the parent material, and if damaged the oxide layer can repair itself immediately, generally speaking the layer is stable in a pH range of 4-­‐9.

So how does aluminum react in chemical environments? Generally speaking aluminum has good resistance to many organic compounds and some moderately alkaline water solutions, and most inorganic salts. As such aluminum materials are often used in the production and storage of many chemicals. One point of interest, for this article involves the pH range. A low or high pH range (below 4 or above 9) can lead to the oxide layer dissolving and corrosive attack. For example inorganic acids, strong alkaline solutions, and heavy metal salts are extremely corrosive to aluminum.

A key takeaway from this article, with respect to aluminum, is that there are important corrosion resistant limitations, and or chemical resistance limitations. For example, aluminum is susceptible to pitting corrosion, this typically happens in the presence of an electrolyte in dissolved salts, usually chlorides. Fiberglass is not susceptible to pitting corrosion in the presence of chlorides.

As with any material, limitations of one create opportunities for others. For example, aluminum is not compatible with, and should not be used in applications that included hydrochloric acid or sulfuric acid. Similarly it is not recommended for service environments that contain chlorine, sodium hypochlorite and ferric chloride, thus making it not an ideal candidate for some wastewater treatment applications.
Conversely, fiberglass has excellent corrosion properties for organic and inorganic compounds, alkaline and acidic environments including chemical resistance to the chemicals mentioned above. Fiberglass is now commonly used in wastewater treatment and or chemical processing applications using sodium hypochlorite, chlorine and or ferric chloride.

Similarly, there are structural property limits such as fatigue strength or fatigue limit that must be considered by engineers. For example, aluminum has no defined fatigue limit (fatigue failure eventually occurs) engineers must assess loads and designs for a fixed life. In contrast, when designed properly, fiberglass does not

creep, and has outstanding dimensional stability; fiberglass is strong lightweight and durable and in many cases a cost-­‐effective solution.

To summarize, fiberglass has a higher-­‐strength to weight ratio and better corrosion resistance in a wide range of chemical applications, when compared to aluminum. When working with fiberglass corrosion resistance can be enhanced by modifying the corrosion barrier to design specifications. Both offer design flexibility and some degree cost-­‐effectiveness with respect to reduced maintenance and long life cycles. An important structural difference is that fiberglass is anisotropic, while aluminum is isotropic. Both are limited by manufacturing processes and design.

Beetle Plastics to Attend The Chemical Processing Symposium

Beetle PlasticsWe are excited to announce that Beetle Plastics will be exhibiting at booth #117 at The Chemical Processing Symposium at the Galveston Island Convention Center November 6-7 in Galveston, TX.

The Chemical Processing Symposium’s focus is on providing the newest research, case studies, and best practices for the management of chemical corrosion with non-metallics. Beetle Plastics will be sharing information about the corrosion resistant abilities of fiberglass reinforced plastics (FRP).

Check out some of our most popular corrosion resistance blog post:

Reducing Material Costs with Corrosion Resistant FRP Solutions

Chemical Handling: Corrosion Resistant Tanks and Vessels

What is an FRP Corrosion Barrier?

Come visit Beetle Plastics at booth #117 November 6-7 at the Galveston Island Convention Center, or contact us to learn more about corrosion resistance and FRP.

Corrosion Resistant Material

corrosion resistant material When looking for a corrosion resistant material for construction or manufacturing, there are a lot of material options on the market to choose from. When trying to sort through the options one corrosion resistant material stands out: fiberglass reinforced polymer (FRP).

Advantages of FRP

There are a number of advantages to FRP as the corrosion resistant material of choice. Once of the biggest advantages has to do with the cost effectiveness of FRP. While other traditional materials like steel or concrete continue to see annual price increases, FRP remains affordable. FRP also has a long service life, making it cost effective in the long term even if it is comparable in price in the short term.

FRP also offers the advantage of flexibility and customization. Working with an experienced company, FRP can be formulated to meet almost any need across a wide range of industries.

How is the Corrosion Barrier/Liner Created?

Corrosion resistance of FRP is a function both of resin content and the specific resin used in the laminate.  Generally speaking, the higher the resin content, the more corrosion resistant the laminate.  Ergo, when building the laminate, the surface area nearest the corrosive or caustic medium is 90% resin and 10% glass (i.e. surfacing-veil layer).  For instances where an extremely corrosive media is present the surfacing-veil layer is then followed by a layer comprised of 75% resin and 25% glass.  Higher glass content may be used where less corrosive resistant qualities are needed.

Corrosion Resistant FRP Applications

FRP is corrosion resistant enough to accommodate a diverse variety of applications including:

  • Hydrochloric acid               
  • Wet chlorine gas
  • Ferric chloride                  
  • Hydrogen sulfide                   
  • Sludge storage                                 
  • Raw and pure water
  • Acid waste neutralization      
  • Caustic storage
  • Industrial waste water                       
  • Industrial water                      
  • Cement industry waste water
  • Oily waste water
  • Chlorides 

Contact us to request a quote or to learn more about the corrosion resistance of FRP.

FRP Ductwork Ideal for Corrosive Applications

FRP ductworkFiber-Glass-Reinforced plastics (FRP) are used for a large variety of applications across a huge number of industries; from boats to bathtubs to missiles chemical storage, FRP is creeping into every aspect of our lives. And there’s good reason for that!

FRP offers a lot of advantages over traditional building materials. For one thing, traditional building materials have been steadily increasing in price for years. FRP, on the other hand, continues to be affordable. FRP also has a long service life, often times making it the most cost effective solution, especially in corrosive environments.

Because of the formulation of FRP, one of the most sought after advantages it offers is its corrosion resistance. And one of the fastest growing areas of FRP use is the use of FRP pipe and ductwork for pollution-control equipment.

FRP ductwork and pipe can be used for:

  • Full vacuum and pressure services
  • Filament wound or contact molded
  • Wide variety of joints available
  • Full range of fittings and connections
  • Standard materials or custom formulations including abrasion resistant composites
  • Round, elliptical or rectangular ducting

Because of the incredible flexibility inherent in FRP construction, FRP ductwork can be specially designed and fabricated for the particular application and environment it will be placed in. And, when working with us, site assistance and testing services ensure that the FRP ductwork and piping are installed and function optimally.   

frp ductwork for mining

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Corrosion Resistant FRP in Sulphuric Acid Processing Plants

Recently, Ashland Performance Materials put out an interesting white paper about the use of FRP in Sulphuric Acid (H2SO4) processing plants. G. Bruce Garret, John Recar, and Don Kelley’s “Fiberglass Reinforced Plastics Applications in Gas Cleaning Systems of Sulfuric Acid Plants” looks at the benefits of using FRP in sulphuric acid processing plants, rather than other materials like lead-lined steel or brick.

‘The development and application of fiberglass reinforced plastics construction over the last 20 years have made lead and brick-lined equipment a thing of the past for sulphuric acid plant gas cleaning systems.” The low cost of FRP, when compared with other traditional materials, also makes FRP an attractive and cost effective solution.

The two most common types of H2SO4 processing plants are sulfur burning (hot gas design) and metallurgical/spent acid regeneration (cold gas design). In the second type of plant, metallurgical/spent acid regeneration, “by-product SO2 gas from smelter processing sulfides of iron, copper, zinc, lead, nickel, molybdenum, or other metal is used.” This gas contains a number of contaminates and, “If not removed, the contaminants will reduce product acid quality, foul the mist eliminators and catalyst beds, and accelerate corrosion of equipment in the acid plant.” This is where FRP comes in.

Purifying the gas from these plants is a corrosive job and, in the past, the equipment designed to handle these jobs was created from “lead-lined steel with acid-proof or carbon brick added for protection.” However, this material solution left a lot to be desired. In addition to be requiring long construction times, plant down time, and intensive on-going maintenance this solution also posed health hazards.

The introduction and continuing improvements to FRP technology over the last 20 years has made FRP the preferred material solution for gas purifying equipment in H2SO4 processing plants. In addition to natural corrosion resistance, FRP allows for easier maintenance, repairs, and is a lower cost material solution.

The clear advantages of FRP have made FRP the standard material solution for all types of storage and handling equipment in the H2SO4 processing industry.

Reducing Material Costs with Corrosion Resistant FRP Solutions

reducing material costs with frpAcross a wide range of industries, material and metal costs are rising. Added to the increase in materials cost is the cost of damage caused by corrosion. A recent Owens Corning whitepaper, “How to Use FRP Material to Lower Corrosion Costs” by Mathew Lieser, discusses the application of fiberglass reinforced polymer (FRP) across industries to help curtail these rising costs.


What is corrosion? “During the process of corrosion, an engineered material actually disintegrates into its constituent atoms as a result of chemical reactions with its surrounding environment. Corrosion can be concentrated locally to form a pit or crack or it can extend across a wide area, almost uniformly corroding the surface.”

The damage caused by corrosion adds up to billions of dollars in repair costs worldwide. Since the installation of most of these corroding materials, FRP materials have been designed that have the ability to withstand corrosion. While there are other options for fighting corrosion, like surface treatments or coatings, FRP offers by far the most economical corrosion resistant solution. FRP solutions have also had over 50 years of tested service experience, “FRP is now a proven material technology.”

The 5 Steps

Although FRP material solutions used to have a higher upfront cost than other materials, like steel, the recent rise in metal costs have made even upfront FRP material costs less. The long service life and lower maintenance costs of FRP, coupled with lower upfront costs, make FRP ideal for lowering overall building costs.  To fully utilize the corrosion and money saving properties of FRP Lieser offers up a five step system.

  1. Identify suitable applications for FRP material
  2. Implement company FRP material standards
  3. Use existing governing standards to have FRP equipment made for use in corrosive environments (ASME, ISO, ASTM, etc)
  4. Specify proper materials (glass fiber, resin, corrosion barrier) to construct the FRP application
  5. Implement proper inspection protocols

To learn more about the five step and download the full Owens Corning whitepaper, click here.