Corrosion is traditionally a major expense in chemical storage and handling applications. During discussion on this subject, visions of coatings, liners, special alloys and reinforced plastics invariably spring to mind.

Double wall secondary containment system. Photo - ZCL

Corrosion is also experienced in applications ranging from the storage of water treatment chemicals to wastewater neutralization tanks to de-ionized water tanks.

ZCL Fiberglass, a Division of ZCL Composites Inc., specializes in the application of fiberglass reinforced plastic (FRP) technology. Most predominant has been its use for the reliable and long-term underground storage of petroleum products.

Before any declaration that FRP is a panacea for all that ails modern industry, one must understand the nature of the problem. As for any application, it is essential that the right material be selected so as to ensure the best performance over the intended lifespan.

Some advantages of fiberglass reinforced plastic (FRP) include corrosion resistant resins developed for specific purposes that have withstood the tests of time and service. FRP equipment typically is moulded with a minimum of welds or joints exposed to corrosive materials, thus minimizing the opportunity for corrosive attack at these locations.

The smooth surfaces of moulded FRP are less likely to support biological growth and are easier to keep clean. This has significance for long-term corrosive effects, health considerations and even downstream equipment fouling. The lightweight nature of fiberglass reinforced plastic (up to five time lighter than steel), facilitates installation and, when applicable, relocation of the equipment.

Most tanks are available in single wall and also in double wall designs for critical applications.

FRP is an effective thermal and electrical insulator resulting in reduced heat loss compared to metal, and no induced current corrosion. It is not subject to any significant long term material creeping, which can be experienced with unreinforced thermoplastics. Larger tanks operating at higher temperatures can be produced and FRP storage tanks usually cost less than many alloys and exhibit lower long-term maintenance costs than many coatings and liners.

The design of a tank must take into account not only the material being stored or processed but also the conditions under which the equipment will be installed (outdoors, indoors, underground, space restrictions, etc.). Tank operating conditions (temperature, pressure) are also features that must be assessed in completing the optimum design for the intended application