What is a common application of epoxy coating in water treatment?

Epoxy coatings are widely utilized in water treatment facilities primarily for their protective qualities, particularly against corrosion. The inside of steel pipes is susceptible to wear and degradation due to the constant presence of water and various chemicals involved in the treatment process. By applying epoxy coatings to the interiors of these pipes, facilities can significantly extend their lifespan by creating a reliable barrier that resists corrosion, abrasion, and chemical reactions. This not only helps maintain the structural integrity of the pipes but also ensures that the water remains uncontaminated.

While the other options describe uses for coatings and sealants, they do not align with the specific and key function of epoxy coatings in the context of water treatment. Painting tank exteriors typically involves different materials aimed at weatherproofing rather than preventing internal corrosion, sealing joints may involve various sealants that do not provide the same level of protection, and insulation is more about thermal protection than addressing the corrosive environment within pipes. Therefore, coating the inside of steel pipes is recognized as a key practice in maintaining the effectiveness and safety of water distribution systems.