Many different heaters and heating applications are used across multiple industries around the world, but what exactly is industrial process heating, and why is it important?

Simply put, industrial process heating is when an industry makes use of heaters (or other heat processing equipment such as ovens, dryers or burners) and the heat that they produce to accelerate, complete and run their operations. There are a number of applications of industrial heating used in the world today. Myriad industries — from the asphalt industry, to oil and gas, to chemical refining to food processing — make use of heaters in their manufacturing processes.

Demand for quality means that the use of adequate, controlled heat is required in many industrial operations. Electric heaters offer good control over process temperature.

Another reason for the use of industrial heating has been the changing temperature patterns and an increase in the strength of winters across the United States. This has especially hit the industrial-abundant states hard. The industry, the machinery and production can be halted as a result of the layers of cold and snow. In those areas, the need for heating equipment that can be used to heat, melt or maintain certain temperatures is cyclical.

Use of Industrial Heating to Reduce Viscosity

One important application of industrial heating is heating heavy liquids, including crude oil derivatives and crude oil itself. Electric heaters are used to reduce the viscosity of these fluids. Reducing viscosity can increase the mobility of the fluid. When you are working on a large scale, as most industries work, it takes more power to pump heavy crude oil when the temperature falls and the oil becomes viscous. Providing heat to the crude oil reduces the viscosity of the oil, making it easier to work with.

In most process heating applications, specific temperatures must be maintained, and heating crude oil and its derivatives is just the same. Overheating the crude oil can degrade or even destroy product quality. Effective temperature control is needed to avoid overheating or burning the oil while heating it to reduce viscosity.
Typically, indirect heating is used for such purposes. The heaters transfer heat to a medium that is used to heat the oil. The oil is protected at all times and does not become overheated.

The heating is provided through the side of the adjacent well. Skid systems — packaged systems supplied with the heaters attached — can be used for heating applications in remote locations. These systems are designed to tightly control temperature and ensure that the oil degradation is decreased to an almost-zero level.

For some viscosity-reduction applications, direct heating using immersion heaters can be used. As the name suggests, immersion heaters are submerged into the liquid, and the heat is supplied directly into the liquid. This means that there is minimal heat loss, and there is greater heat efficiency.

Use of Industrial Electric Heaters in Kilns and Dryers

Another common heating application is the use of heaters in biomass dryers. These dryers are offered in a number of configurations and heating systems. However, to do that, a number of plant-specific variables must be considered. Decisions regarding dryer configuration will ensure the amount of maximum energy and output that is produced.

Another application that requires the use of industrial heaters is lumber kilns. Because each facility and wood species is different, each application has its own specific needs. Traditionally, fuel oil or natural gas was used as a primary energy source. Some lumber mills also used burnt wood waste produced as a byproduct of manufacturing at the plant. In some cases, wood waste was able to entirely replace fossil fuels; in others, it offers supplemental process heating.

Some newer lumber mills have switched to industrial heaters to ensure that the heating application can be carried out without fail. The strength of the heating application and the way that it is put into use will also dictate how efficiently the kilns and dryers will be in terms of production.

In conclusion, industrial heating applications have become one of the most important operations in industry today. This piece focused on the more unconventional uses of industrial heating. Despite the fact that a number of companies may find funding the industrial heating through electric heaters hard, most are willing to do it. This is largely due to the fact that industrial electric heaters:

  • Offer good control of the temperature.
  • Allow the owner to keep track of where the heat is being provided.
  • Ensure there is minimal heat loss and greater efficiency for the business.

Before choosing an industrial heating application for your business, however, it is important that you take into account the scale of your operations and how that will impact the use of these heaters.

What Kind of Immersion Heater Do I Need?

For smaller applications, screwplug heaters offer relatively low cost and ease of replacement. For larger applications, flanged heaters are able to handle high power loads and larger liquid volumes. For applications that require elements inserted from the top of a container, over-the-side heaters can be selected. Most electric heaters can incorporate a mechanical thermostat or a digital controller for more precise temperature requirements. Options may include a NEMA 1 terminal housing, a NEMA 4 moistureproof housing or a NEMA 7 explosionproof housing for more volatile environments.

How Often Should I Maintain the Heater?

Heaters should be maintained on a regular basis. Depending on the medium you are heating, each application should be thought out carefully. Water-based liquids might have calcium deposits that stick to the sheath. Heavy water should be treated to prevent calcium deposits (normally identified as a white powdered substance) from sticking on the individual elements.

Do I Need A High Limit Safety Switch?

High limit safety switches are an inexpensive and valuable tool to help protect heaters and the solution you are trying to heat. Often inserted into a thermowell within the bundle of elements, they are set to a maximum temperature range that would shut off in case of overheating.

Do I Need a Mechanical Thermostat or a Digital Controller?

Mechanical thermostats are an inexpensive tool to set your temperature of your heater using a capillary and bulb that is inserted in a thermowell within your heater. The limitations of this device are the amperage load it can handle (often around 15 A for a three phase and 25 A for single phase).

Applications that require more precise measurements use digital controllers that have relays, fuses, contactors and are offered in various NEMA housings.