How Protective Coatings Safeguard Industrial Pretreatment Systems

• Concrete Assets – Concrete is porous, alkaline and prone to chemical attack, microbial growth and cracking from thermal cycling. Thin-film epoxies often fall short in these environments. Thick-film systems – especially 100% solids epoxies reinforced with glass flake or mat – offer greater protection. In highly aggressive zones like MBR basins, which are cleaned with 2% citric acid, even more robust systems may be needed. One solution involves applying a base layer of Sherwin-Williams Dura-Plate® UHS Clear Laminate, embedding a 1.5-ounce fiberglass mat (Figures 1 and 2), sealing it with more laminate and topping with Dura-Plate® UHS Epoxy White (Figure 3). This high-build system delivers strong edge retention and reinforced durability against harsh exposure.

• Steel Surfaces – Carbon steel is often preferred over stainless in pretreatment systems, particularly where chlorides are present – but it remains vulnerable to corrosion and undercutting if left unprotected. High-build novolac epoxies such as Sherwin-Williams Nova-Plate® UHS and Dura-Plate® 8200 are engineered for immersion zones and provide excellent edge retention and durability against acids, solvents and thermal shock. For added protection at weld seams, bolts, edges and other high-risk areas, applicators often begin with a stripe coat of Dura-Plate® UHS Primer (Figure 4). This ultra-high-solids, two-component epoxy amine delivers strong surface wetting and adhesion – ideal for immersion service. In particularly aggressive conditions, including heated hydrocarbon exposure or oxidizing agents, glass-flake-reinforced novolac vinyl esters may be required.

• Hybrid or Transition Zones – In many systems, concrete and steel are joined within the same unit – such as steel tank walls embedded into a concrete floor. Here, transition zones must be reinforced with fiberglass matting and flexible epoxy layers to handle differential movement and prevent cracking. Installing 45-degree cant coves and edge wraps at vertical-to-horizontal interfaces provides an added layer of integrity and stress relief.

No matter the material, effective coating selection means going beyond what’s simply adequate. With dozens of proven systems available, the best choice is the one that matches your specific environment.

Strategies Across Sectors

Across industries, customization is critical in choosing coating chemistries. This helps account for the interplay between substrate, temperature, exposure duration and cleaning regimen.

• Semiconductor Manufacturing – In chip fabs, ultrapure water (UPW) is a baseline requirement – yet the effluent these plants produce is anything but pure. Wastewater streams can include hydrofluoric and sulfuric acid, solvents, photoresists, heavy metals and even PFAS compounds. Pretreatment systems often include neutralization tanks, fluoride removal, advanced oxidation and closed-loop recycling. Linings must withstand aggressive chemistries and high-purity standards. Glass-flake reinforced novolac vinyl esters are often the material of choice for immersion zones – offering exceptional chemical resistance without shedding particles that could compromise cleanroom standards.

• Pulp and Paper – Paper mills generate large volumes of wastewater containing lignin, fiber residues, acids, bleaching agents and occasionally chlorinated organics. Equalization tanks, clarifiers and lagoons must handle fluctuating pH, abrasion and microbial contamination. Linings must be robust enough to withstand chemical cycling and long-term immersion. Coatings like Dura-Plate® 8200 or reinforced novolac epoxies can provide reliable protection in high-load environments.

• Food and Beverage Processing – From dairy and meat to beverage bottling, FOGs, sugars, proteins and sanitizing agents all wind up in wastewater streams. Facilities rely on DAF tanks, pH adjustment chambers and MBRs to clarify water before discharge. These units often combine stainless steel, carbon steel and concrete. Coatings must stand up to acidic waste, cleaning cycles and microbiological attack. Novolac epoxies, thick-film barrier systems, and fiberglass-reinforced laminates are common choices to promote durability and compliance.

• Energy and Chemical Processing Whether refining petroleum or generating power, energy facilities produce wastewater laced with hydrocarbons, salts and elevated temperatures. Thermal shock and contact with corrosive substances pose significant challenges. Here, vinyl esters, novolac amines and fast-return epoxy linings allow for safe, efficient operation while improving asset lifespan.

Facilities that invest in customized solutions gain more than corrosion resistance: they gain confidence in compliance, uptime and long-term performance.

Installation and Inspection

Even the most advanced coating system can fail – if it’s applied without proper preparation or oversight. Long-term success depends not only on product selection, but on how the system is installed, verified and maintained.

That process begins with surface preparation. For both concrete and steel, this typically means abrasive blasting to achieve the specified surface profile, removing laitance or rust and eliminating soluble salts that can interfere with adhesion. Rushing or skipping prep steps can lead to delamination, moisture ingress or corrosion beneath the coating.

Environmental conditions also matter. Substrate temperature, ambient humidity and dew point must fall within product tolerances. For concrete, moisture vapor emission rates may require mitigation primers to avoid blistering. Every coating layer must meet required film thicknesses and be properly cured before the next is applied.

In active plant environments, installation must be carefully planned around downtime windows. Many facilities schedule shutdowns over weekends or holidays, making fast return-to-service coatings – some of which cure in 10 to 24 hours – a valuable option for minimizing disruption.

Application logistics are equally important. Pretreatment infrastructure often features complex geometries, embedded steel or hybrid materials. For example, where steel meets concrete, cant coves reinforced with fiberglass mesh and sealed with high-build epoxy help absorb thermal movement and reduce stress on the lining system.

Today’s coatings can also simplify application: many are designed for single-leg spray equipment, reducing cost and broadening access to qualified applicators. Still, performance ultimately depends on experienced crews who understand the nuances of surface prep, coating chemistry and field conditions.

Once installed, systems require periodic inspection and maintenance to maintain integrity. Coatings degrade gradually with exposure – and early touch-ups can prevent costly full recoats. Many facilities with proactive maintenance programs extend asset life by 50% or more.

To support success, coatings experts often provide site surveys, specification updates and training for contractors or in-house teams – helping maintain long-term performance.

Figure 1. An especially robust protective coating system for MBR basis may include reinforcement with fiberglass matting. In this installation, applicators applied Sherwin-Williams Dura-Plate UHS Clear Laminate as a base layer and then tinted the material green to provide contrast when sealing in a 1.5-ounce fiberglass mat for reinforcement.

Figure 2. Using aluminum fiberglass rollers, the applicators worked the green-tinted laminate material into the matting to ensure full wetting and proper adhesion.

Figure 3. For the final layer of the MBR basin linings, applicators spray-applied Dura-Plate UHS Epoxy White, an ultra-high-solids epoxy amine coating engineered for immersion service that features high-build, edge-retentive properties for superior protection.

Figure 4. For added protection in steel tanks, applicators commonly apply stripe coats of Dura-Plate UHS Primer, using a combination of brushing and rolling techniques, to ensure full coverage on weld seams, bolts and edges.