Industrial Immersion Heaters in the Nuclear Power Industry

An Insight on Industrial/Immersion Heaters in Nuclear Power Industry

The typical uses of industrial immersion heaters include heating:

  • Chemicals
  • Liquids
  • Gases
  • Food processing

But their applications reach far beyond. These industrial heaters are essential in many sophisticated processes. Such as the coal and mining industries. Another significant use of this device is in the nuclear power industry, where the immersion heaters generate heat and electricity.

Operating Process

The nuclear power industry provides heat and electricity through nuclear fission. This process occurs within a closed and controlled space to avoid damage.

In nuclear fission, the nucleus of the atom breaks into smaller parts. This requires caution and precision. If the process is not controlled it can start up a chain reaction. The results of which can cause severe damage to equipment and can be potentially fatal.

Inside of the nuclear reactor, fission produces an extent of thermal energy. This process heats the water, transforming it into steam. The steam moves the turbine within the electrical generator, transforming this thermal output into electricity. Fission, as well as the generation of electricity and heat,  is carried out with the use of immersion heaters.

Essential Factors of Nuclear Energy

Nuclear energy is a major source of electricity production. Approximately 14% of electricity distributed and produced around the world comes from nuclear plants.

Nuclear fission and all the other process within the turbine require extreme care. While nuclear is efficient and provides clean energy there are risks if safety precautions are not followed.

Control systems and monitoring devices are available, such as thermocouples and control panels. These allow for effectively carrying out processes where immersion heaters apply heat generation.

Working of Immersion Heater

An immersion heater contains a metallic element, also known as a heating rod. The rod is coated with a sheath to prevent deterioration from exposure to chemicals. Since the heater is immersed directly into the target medium to maximize heat distribution, materials must be able to withstand the medium.

Flanged heaters use different alloys of metal depending on the application. Circulation heaters use flanged heaters that are encased within a pipe that contains fluid that is to be heated. This particular element is also used as an electrical reactor that turns electrical energy into heat. The heat is then evenly distributed over to its surrounding. Thus heating the entire turbine.

The heater uses sensors to monitor temperature levels, activating or turning off the device. Careful monitoring allows one to control the heat distribution evenly without dissipating it.

Inside The Reactor

Pressurized water reactors are a common type of nuclear reactor. These industrial electric heaters control and maintain this pressure within. High-pressured water acts as a basic coolant in this type of reactor.

The fluid absorbs the heat released due to the fission process. Afterwards, and industrial heaters transmits this heat to water. Heating the water produces steam, spinning the turbine and generating electricity.

It is important to keep the water constantly in a liquid form even when the temperature rises to 321℃. For assurance that the water does not boil, the loop of the device is kept at a high-temperatures and high-pressures, up to 2250 psi.

The pressure vessel, or tank, connects to this loop. It contains the water and steam. The industrial electric immersion heater is installed at the bottom of this tank. Flange or screw plug heaters are common for this task.

The electricity produced depends on the watt capacity of the heater. For instance, an 1800 KW heater produces 3000 MWe electricity in a nuclear plant.

When the sensors read a pressure drop, the heater turns ON automatically. If the pressure rises higher than the desired level, cool water is released in the tank. This lowers the temperature and pressure of steam.

Design & Specification of Immersion Heaters

Most nuclear power industries prefer the use of immersion heaters because of their:

  • Size
  • Performance
  • Efficiency
  • Versatility

Different types of immersion heaters vary in their operating mechanisms. So this depends on which type the buyer selects.

It’s essential to keep the heating device clean and maintained to keep the reactor and heater operating at maximum capacity. It also extends the lifespan of the heater and reduces the frequency of repairs.

If there is any need to replace the heater for maintenance, you can easily remove the entire device with simple cutting and welding.

Engineers prefer to use stainless steel alloy as the sheath material for these heaters. The material is high-quality and has corrosion-resistant properties. As well as the ability to withstand extreme temperature. For this reason, many immersion heaters are used during the piping process inside the reactor.

Electric heaters can use steel alloys but their appropriateness depends on the process and heated medium. For instance, the radiation released from the bowels of the reactor can corrode steel. Corroded heaters can disrupt the entire process of generating electricity.

For this reason, it’s best to use heaters made with strong sheath materials, like Incoloy and Inconel. These are both heavy and sturdy enough to withstand nuclear reactor processes.

Suggested Applications of Flanged Heaters

The application of and immersion heater determines its ideal sheath and flanged material. Given below is a table for choosing the right configuration for an application.

Applications Sheath Material Flange Material
To clean water, protection against freezing, storing hot water, cooling towers. Copper Steel
In hot water, boilers which use steam as a heating medium and within mildly corrosive solutions. Incoloy Steel
Gases, oils (both stagnant and heavy), low flowing gases. Steel Steel
Soaps and detergent solutions, processed and de-ionized water. Stainless Steel Stainless Steel
Weak corrosive liquids and chemicals. Stainless Steel Stainless Steel
Excess corrosive chemicals and de-ionized water. Incoloy Stainless Steel
Light and Medium oil. Steel Steel
Food processing and related equipment. Incoloy Stainless Steel