How to keep a water storage tank from freezing in winter
The increasingly lower temperatures of winters present a massive challenge for cold climate operations. If your water/propane tanks freeze or even approach near-freezing temperatures, you’re in for a frustrating and costly experience. This is why heating for cold climate operations is one of the essential activities of the year.
This article will explore the activity of winterizing aboveground storage tanks with electric heaters alongside various valuable tips.
Water storage tanks
Water storage tanks are one of the most common aboveground outdoor tanks. They are used for various purposes, like supplying water to cooling towers, providing potable water, sprinkler reservoirs, greywater, etc.
However, water has a considerably high freezing point of 0℃, making freezing a significant concern in pretty much the entire northern hemisphere. This is not so much because water will be damaged by freezing, but because frozen water can cause extensive damage to systems and equipment. It can potentially destroy everything, from the storage tank itself to the plumbing and piping systems.
Thus, freezing water in winter will lead to:
- Expensive repairs
- Lost revenue due to halted operations
Fortunately, you can avoid these by using passive and active antifreeze techniques. Passive techniques include using antifreeze additives and choosing the proper storage tank insulation. Others include:
- Using large tanks because according to the laws of physics, the larger the body of water, the longer it will take to freeze.
- Monitor cracks and leaks as they allow the cold to permeate into the tank more easily. This speeds up the freezing process.
- Use a sloping tank cover because flat top tanks enable a gradual buildup of ice, reducing the temperature of the tank’s water and increasing the chances of freezing.
- Round tanks have a smaller surface area than cube-shaped and rectangular ones. Thus, they lose less heat to the environment and provide better insulation.
On the other hand, active techniques are best suited for situations where some passive techniques are impossible. One such case is cooling towers; you cannot use antifreeze in the water. Instead, active solutions like inline water heaters are preferred. They are also an excellent way to complement passive heating techniques.
Inline heaters make for cost-effective yet efficient ways to winterize above-ground water tanks.
Propane tanks
Most large propane tanks are kept outside to leave indoor space for other operations and reduce the potential damage in case of leaks or an explosion. And while this is a good safety strategy, it also leaves propane tanks vulnerable to the cold, freezing temperatures of winter.
Propane freezes at temperatures below -42℃ (-44℉), which is pretty low. However, partial freezing can occur at ambient conditions above 42℃. This presents more or less the risks of complete freezing, including;
- Tank failure leading to severe safety hazards
- Reduced tank efficiency. This is still a problem even where temperatures don’t drop to such extremes. As the temperatures drop, so does the pressure, which depletes the propane volume. This, in turn, affects the gases extraction rates, resulting in inefficient and unpredictable operations.
How to passively keep your propane tank from freezing
- Keep it full: A full propane tank is less likely to freeze than an empty one. Thus, refilling your tank as often as possible is one way to protect your gas.
- Keep up the pressure: Changes in pressure as the propane contracts due to ambient weather caused by dropping temperatures can also cause your tank to freeze up. To maintain the pressure, keep the propane tanks clear of snow, don’t let them drop below 30% capacity, store the cylinders in an upright position, and make sure that the valve is turned off when not in use.
Unfortunately, sudden temperature drops in winter mean that most passive solutions alone aren’t as effective with propane tanks. You’ll also need active solutions, like electric heaters. These can include immersion heaters or external heaters, like heat trace cables and pipe heaters. Immersion heaters are the most efficient option that allows rapid and even heating of even large propane tanks.
Heaters for storage tanks freeze protection
Rama Corporation is one of the leading manufacturers of electric heaters in the USA. We make heaters for all kinds of storage tanks; indoor, outdoor, belowground, or aboveground vessels. Contact us today and work with our engineers to find yourself the best heaters based on your budget and specifications.