Asphalt Storage Tanks

There are a number of important things to keep in mind when you’re in the business of storing and handling liquid asphalt. Some of the top ones include:

• Temperature Control: Liquid asphalt must be stored at consistent temperatures to prevent hardening or degradation. The proper temperature to store liquid asphalt is typically between 275°F and 350°F, depending on the specific grade.
• Tank Design and Construction: Storage tanks need to be designed to withstand the high temperatures of the liquid asphalt. What you will find common to many tanks are:
  • Insulated walls and roofs to minimize heat loss.
  • Robust materials like carbon steel or stainless steel to handle extreme conditions.
  • Thermal expansion allowances to accommodate volume changes.
• Mixing and Circulation: You must be able to regularly mix/circulate the liquid asphalt to maintain a uniform consistency and prevent the separation of additives or polymer modifiers.
• Safety Measures: Proper ventilation, emergency shutdown systems and of course being OSHA and NFPA compliant are a must.
• Environmental Considerations: Storage tanks should include vapor recovery systems, spill containment areas, and proper insulation to reduce energy consumption.
• Loading and Unloading: To make sure using the storage tanks is easy and doesn’t harm the liquid asphalt, features like piping insulation, heat tracing, and leak-proof fittings are recommended.
• Regular Maintenance and Monitoring: Liquid asphalt tanks are not a set it and forget it product. To get the most out of them, and to make sure they last as long as they are designed for, routine inspections are needed. Using advanced monitoring systems can also help automate processes and improve overall performance.

Liquid asphalt is typically stored at a temperature between 275°F and 350°F. The different features of a storage tank that help to maintain this temperature include:

• Insulation: Storage tanks are insulated with materials like fiberglass, mineral wool, or foam to minimize heat loss. It is not just the walls that are insulated. Quality tanks will also have insulated roofs and sometimes insulated floors.
• Heating Systems: To keep the temperature of the liquid asphalt hot, the storage tank may use a hot oil heater, electric heater, or direct-fired system.
• Heat Tracing: Electric or steam heat tracing systems on pipes and valves prevent heat loss and blockages during loading and unloading.
• Circulation Systems: To make sure heat is distributed evenly within the liquid asphalt, the asphalt can be mixed within the tank.
• Temperature Monitoring and Control: Use of automated sensors take the temperature of the liquid asphalt on a continuous basis. If the temperature drops below a threshold a heating mechanism will turn on.
• Standby Heating: If the liquid asphalt is not used all that often, a system that keeps the product warm will conserve energy consumption between times when it is needed.

There are a handful of common heating systems used in asphalt storage tanks. The most popular are:

●     Hot Oil Heating Systems: Heated thermal oil is circulated through a network of coils inside or around the tank. This is the preferred system for large storage tanks and facilities that handle asphalt continuously.
●     Electric Heating Systems: Electric heating elements are installed inside the tank or on the tank's exterior to heat the asphalt directly. This system is ideal for smaller tanks or locations where hot oil systems are impractical.
●     Direct-Fired Heating Systems: A burner directly heats the tank or the asphalt. Heat is applied to the tank walls or transferred through flues running through the tank. This is often used in portable or temporary storage tanks.
●     Steam Heating Systems: Steam is circulated through coils or jackets surrounding the tank to heat the asphalt. This will be found in some older storage tanks.

When it comes time to discuss the right heating system for your storage tank, give ECF a call. We’ll analyze the tank size, your budget, energy availability, and the specific requirements to come up with the best solution.

There are a few high quality choices when it comes to materials for your asphalt storage tank construction. The primary ones include:

• Steel: Carbon steel is the most common material used. Its combination of strength, durability and heat resistance is unmatched. If corrosion resistance is required, stainless steel is the preferred option.
• Fiberglass: For instances where a long-life storage tank with low maintenance is need, the storage tank may be made from fiberglass. These will be lightweight, corrosion-resistant, and highly durable.
• Plastic: For smaller and portable asphalt storage needs, plastic is an option. High-Density Polyethylene (HDPE) or Polypropylene are typically considered when flexibility and chemical resistance are key.

There are options when it comes to the insulation materials used in the storage tanks. Choices include:

• Fiberglass (lightweight and thermally efficient)
• Mineral Wool (superior thermal insulation and fire resistance)
• Polyurethane Foam (for a seamless thermal barrier)

For the lining and protective coating of the storage tanks you can choose Epoxy (inside), Thermal Barrier (external) and Aluminum Cladding (insulation cover).

The heating components of your storage tank can be made from steel (steel coils) or high-temperature alloys (electric heating elements), while the foundation materials could include concrete and steel plates. The primary material for piping and valves is steel (carbon or stainless).

We all want to minimize the environmental impact we have while storing and handling hot asphalt, but we also want to maintain our operational efficiency. As we keep this in mind, here are some of the top considerations when it comes to the environment and asphalt storage:

• Emission Control: The use of Vapor Recovery Systems and Low Emission Burners can limit emissions during heating and storage of the asphalt.
• Spill Prevention and Containment: To minimize environmental damage due to spilt asphalt, sites should install Leak Detection Systems and Secondary Containment Systems.
• Insulation and Energy Efficiency: High quality insulation and efficient heating systems mean less energy is used to operate asphalt tanks.
• Stormwater Management: Proper drainage systems will help prevent rainwater and local water sources from becoming contaminated.
• Proper Waste Management: Any leftover product or cleaning agents should be disposed of according to local and federal regulations.
• Environmental Compliance and Certifications: Read up on all regulations (i.e., EPA) and codes and make sure to use equipment and materials that meet environmental standards.
• Sustainable Practices: Recycle whenever possible. Check into the feasibility of using alternative energy sources to run your facility.