Blog – Paintings and Coatings

Surface Preparation and Coating Tips for the Petrochemical Industry

Considering the contents of storage tanks in the petrochemical industry, it’s vital that they remain structurally sound for the sake of public health and safety, as well as the environment. The petrochemical industry often uses steel to hold and protect its products because of its strength. As a metal, steel is vulnerable to the damaging effects of corrosion, necessitating the need for protective coatings on tank surfaces. The success of these coatings largely relies on the quality of the environment in which such projects are performed.

The Cost of Corrosion in the Petrochemical Industry

The expenses related to corrosion in the petrochemical industry have significant financial impacts on U.S. infrastructure, transportation, utilities, and production and manufacturing. In 2002, NACE International reported the direct annual costs of corrosion within various sectors of the petrochemical industry as follows:

  • Corrosion in aboveground and underground storage tanks containing hazardous materials: $7 billion
  • Gas and liquid transmission pipelines: $7 billion
  • Petroleum refining: $3.7 billion
  • Petrochemical, chemical and pharmaceutical production: $1.7 billion
  • Oil and gas exploration and production: $1.4 billion

The Need for Surface Preparation and Coating in the Petrochemical Industry

Corrosion presents more than a financial setback. In the petrochemical industry, it also poses numerous health, safety and environmental risks because of the hazardous and flammable materials stored in the tanks. Regular tank maintenance that includes proper surface preparation and coating ensures the strength, design and performance of the original tank while preserving its contents.

A protective coating on a tank creates a barrier between its surface and environment to prevent and control corrosion. When a coating fails and corrosion persists, fault lines that are vulnerable to fatigue failure form, increasing the risk of leaks and decreasing the tank’s structural integrity. Without proper corrosion management, affected areas on a tank might require costly steel renewals, further driving maintenance costs.

Temporary climate control technologies create an environment that promotes a tank’s successful surface preparation and coating. Ventilation systems keep surfaces free of salts and debris. Humidity and temperature controls maintain ideal temperatures while keeping relative humidity low, regardless of the weather.

Tank Surface Preparation and Coating Tips

  • Keep the surface clean: Moisture, salts, oil, weld spatter and fumes, dust, and ionic species on a tank’s surface affect a protective coating’s performance and reliability. The best way to clean and prepare a tank depends on its age, the types of contaminants on its surface, and the previous protective coating. Abrasive blasting and solvents are among the most common cleaning agents. When cleaning a tank’s surface, ensure that fasteners also receive proper attention.  
  • Prepare the edges: Coatings tend to pull away from sharper edges, leaving a thin, ineffective layer. Clean cut edges and grind them so they’re round to improve a coating’s coverage and adhesion.
  • Maintain ideal temperature and relative humidity levels during the surface cleaning and preparation process: If ambient conditions are not ideal, they may hinder your preparation and coating efforts. When preparing a tank, surface temperatures are as important as air temperatures because metal absorbs heat during the day and radiates it at night. The temperature changes could lead to the formation of condensation on a tank’s surface if you do not control relative humidity levels. Furthermore, high relative humidity levels could cause flash rust to form on the surface in as little as 30 minutes.
  • Maintain ideal temperature and relative humidity levels before, during and after coating applications: You will experience the best results when you control the ambient conditions from the moment you begin preparing a tank’s surface. Allow the controlled conditions to persist at least 48 hours after the final coating application. Conditions that are too hot, cold, dry or humid will prevent a protective coating from drying and curing properly.

Using the temporary climate control and monitoring solutions that Polygon designs allows you to perform preventive maintenance on tanks throughout the year, rather than wait until conditions are just right. In turn, you’ll reduce maintenance and repair costs, complete projects faster, prevent corrosion, maximize a tank’s service life, reduce pollution and prevent expensive accidents. With the savings that Polygon’s affordable solutions yield, the benefits might be greater than you imagine. Talk with a climate control specialist at Polygon to learn more.

 [Parisien Néerlandais via CC License 2.0]