Tanks are a vital part of so many processes and many of them need to be heated. There are almost as many ways to heat a tank as there are types of tanks.
Steam coils, heat transfer systems, direct immersion, tank wraps, or heat trace; the list goes on and on. Knowing that many different types of heat can be effectively applied would drastically improve the best selection for the application.
Different Types Of Tank Heaters
Powerblanket discusses several methods that can heat a tank that users may have not known about in the past. Steam trace is one exception. It won’t talk about that one much because Powerblanket doesn’t sell steam trace systems.
They’ve been around for over 100 years, and everyone pretty much knows about them. Comparing steam trace to steam engine locomotives is a pretty good comparison when users see some of the new technology available.
Tank heating systems
All tank heating systems technically are not heating a tank. They are heating the product in the tank. Tank heating systems use either a direct or indirect method of heating that product.
- Direct is when a heater is directly placed into the liquid from outside the tank and heats that tank content.
- Indirect is when the product is pumped into a coil system and is not in direct contact with the tank product. Heat is transferred to the process through an exchanger or coil system.
Powerblanket will take a look at several modern effective methods to heat a tank directly or indirectly.
Direct Tank Heating
Flanged immersion/screw plug or pipe insert heaters are installed into a tank and directly contact the liquid
Examples of direct tank heating systems include flanged or screw plug heaters, pipe insert heaters, side arm heaters, or DHG systems. Flanged immersion/screw plug or pipe insert heaters are installed into a tank and directly contact the liquid. The interface or connection point between the heater and tank is generally a pressure-rated flange or NPT connection.
Heater temperature control is done by way of a sensor placed in the tank liquid, and that sensor notifies a temperature controller so that it can decide to add or not add heat. These heaters often utilize a heater sheath over-temp sensor that watches the surface of that heater so that it does not overheat or cause damage to the tank's contents.
Below are several examples of direct tank heaters:
- Flange Immersion Tank Heater
- Pipe Insert Heater
- Side Arm Circulation Heater
- DHG Heater
Indirect Heating
Many times it is not possible or effective to use a direct heater due to equipment internal to the tank like mixers, or the need to contain the liquid by way of double-wall construction.
Indirect heat relies on the tubes or tank wall to transfer heat to the tank contents to either maintain their temperature or heat them. With this in mind, it is important to consider how well the tank wall or the coils used will transfer heat to the process.
Square tank pad heaters
Powerblanket relies on the tank wall attached to transfer the heat to the tank product
A good example would be installing square tank pad heaters on the side of the tank to keep that tank at temperature. Attaching that tank pad heater to the tank, Powerblanket relies on the tank wall attached to transfer the heat to the tank product.
Steel for example is a very common product to make tank walls out of. Steel has a specific heat of .12, which is very poor at conducting heat. Be sure to allow for low heat transfer of steel when taking into account heat transfer.
Below are a few examples of an indirect heater:
- Heat Trace
- Heated Blankets
- Glycol/water or hot oil heat transfer systems
How Do I Select The Right Industrial Heating Solution?
Powerblanket was created to understand and solve heating issues relating to total temperature control.
If users are ready to make a selection, talk to their process heating engineers about which heater control panels might be a good fit for heating processes.