Winter is coming. With increasing climate fluctuations, it looks like we’re going to see colder winters with more extreme temperatures. While heating for cold climate operations is always important, this year it is especially valuable to prepare for winterization.
In this article, we discuss some key tips to winterize your aboveground storage tanks with electric heaters, protecting your equipment and stored contents from the cold and the elements.
Large propane tanks are generally kept outside. This leaves valuable indoor space for other operations in indoor spaces. As well, it helps to reduce the risks that could occur from LPG leaks or explosions. But, this outdoor location means that propane tanks are exposed to the cold and inclement weather.
Cold weather has a direct impact on aboveground propane tanks, increasing risks of tank failure and reducing efficiency. Propane freezes at temperatures below -42℃ (-44℉). While this temperature is extreme, this is a high freezing point compared to most gases. Partial freezing can occur at ambient temperatures above -42℃. Either partial or complete freezing can cause a propane tank to rupture, or otherwise fail, creating a severe hazard.
Even if your climate doesn’t reach these extremes, aboveground propane tanks can still be affected by the cold. As the temperature drops, tank efficiency decreases—well before the temperature required for freezing.
A decrease in ambient temperature causes a pressure drop. This depletes the propane volume, directly affecting the extraction rate. This results in inefficient and less predictable operations.
Temperature drops can occur suddenly, so just insulating your tanks may not be sufficient. Instead, electric heaters are the ideal solution. They are very responsive and are set to only run as needed, keeping heating costs down while protecting efficiency.
External heaters, like heat trace cables or pipe heaters, can provide indirect heat to the tank. This leaves easy access to the heater and allows for easy replacement or repairs.
Immersion heaters are installed directly in the tank, providing direct heat. This is the most efficient option, allowing for rapid and even heating even in large tanks. Careful selection of sheath materials can prevent corrosion damage. And the use of low-level on/off switches reduces the potential for combustion.
Water storage tanks are another common aboveground outdoor vessel. These tanks can serve all sorts of valuable purposes from potable water to supplying cooling towers. Although the water itself won’t be damaged by freezing, frozen water can do extreme damage to equipment and systems.
When stored water freezes, not only is it unusable (at least until thawed), but it can severely damage everything from the storage tank to plumbing and piping systems. These repairs can be expensive and halt operations. As such, freeze prevention is a necessity for water storage tanks.
With a freezing point of 0℃, freeze risks are a major concern in most of the northern hemisphere. To prepare, passive techniques like choosing the right storage tank insulation and antifreeze additives is important. Even still, non-passive freeze prevention is usually advised as well.
This is especially true with uses like cooling towers, where antifreeze cannot be used in the water. Instead, we rely on inline water heaters. These immersion heaters are not efficient and responsive but are cost-efficient. For the purpose of freeze protection, they can usually use copper sheaths and steel flanges, rather than more expensive materials like Incoloy.
Wattco custom manufactures electric heaters for all sizes and types of storage tanks. Aboveground, belowground, indoor, or outdoor tanks. Our engineers work with your project’s specifications and budget to the best heater type, design, wattages, and materials.
Contact us today for storage tank heater quotes and information.