Below-ground storage tanks, commonly used in the storage and/or heating of fuel oils, offer a number of advantages. Being partially, or fully, below ground they leave more room for other operations on-site, even while typically having large capacities. As well, they may provide some shelter from the elements and add additional safety to oil heating processes.
While below-ground storage tanks have these important benefits, they do come with their own challenges. In comparing aboveground to underground storage tanks, the below-ground tanks have more stringent regulations. There are also extra environmental concerns to address and specific design requirements that can increase the build cost. As well, there is less access and room for other operations, making the careful selection of your below-ground tank heater important.
Picking the right tank heater for underground storage vessels is especially important because the lack of space and access makes repairs and replacements more difficult. These factors should be considered in addition to the traditional concerns of other tank heaters such as efficiency and operational costs.
Here we review a few things to explore when choosing an underground tank heater.
For direct heating operations, heater elements are constantly immersed in the target volume. This leaves them exposed to potential corrosion, sediment, and other damage. Although custom element and sheath material selection significantly reduce this damage, elements are often the first piece to fail.
A tank heater with replaceable elements is easier and cheaper to repair. The damaged elements can simply be removed and replaced. This ease of repair is especially important in underground tanks where space is limited. Often, the tank does not even need to be drained to replace elements. As a result, there are fewer and shorter interruptions of operations for repairs and maintenance.
If there are other operations or processes in the storage vessel the type and configuration of your heating equipment are important. Screw plug heaters are generally positioned at the bottom of the tanks, leaving them out of the way of other operations and allowing for even heat distribution.
Electric flanged heaters can be positioned at the bottom or sides of tanks, to keep them from interfering with other processes. As well, they can come with custom element configurations and/or be used in tandem with each other to better heat the specific tank they are used in.
Direct heating is generally superior to indirect heating. Having the heater immersed in the target medium means the heat is transferred directly to it. As such, it takes less time and energy to achieve or maintain target temperatures.
In aboveground tanks, indirect heating options, like heat trace cables are exposed to the elements and easily damaged. While a below-ground tank doesn’t leave indirect heaters with the same exposure, they do experience other issues. Due to space limitations underground, indirect heaters lose the advantage of quick access that they have aboveground.
In most instances, direct heating is the best option for underground tank heaters.
Electric power is rapidly becoming the preferred choice for immersion heaters. In addition to environmental benefits, electric tank heaters also provide a significant improvement in efficiency in comparison to fossil fuel heaters.
Electric immersion heaters achieve temperatures faster and with less wasted energy. This makes them more reliable and decreases operational costs.
Wattco custom-manufactures industrial storage tanks for above and below ground vessels. Our engineers help you select the right heater type, configuration, materials, and wattages to match your project and budget.
Contact Wattco today for storage tank heater quotes and information.