Air heaters play a tremendous role in a variety of industries. Hot air is used for heating spaces, manufacturing, moulding, curing, annealing, sealing, sterilisation, and many more applications. However, some industries require exceptionally hot air for their processes. For this, specialised high-performance heaters are needed.
Industrial air heaters differ in their heat-generating capacities. For example, electric heaters can achieve up to 815°C, while infrared heaters can reach over 982°C. However, gas-fired and specialised process air heaters can exceed 1,093°C, which is necessary for high-heat applications.
Secomak’s heating systems can achieve in excess of 400°C by combining our industrial heaters and unique blowers. Our range of industrial heaters, blowers, and heat packs are the perfect solution for many industries. Read on to learn more about hot air heaters, their capabilities and designs, and their essential role in diverse sectors.
How Hot Can Air Heaters Really Get?
Industrial hot air heaters differ from commercial and residential HVAC heaters in that they must reach higher temperatures. The output temperature will depend on the process and what is being manufactured. Below are some common types of industrial hot air heaters and their temperature ranges:
Electric Air Heaters
Electric air heaters are commonly used where precise temperature control is required. They can achieve high temperatures from 38°C to over 815°C, depending on the heating element, setup, and control systems.
Gas-Fired Heaters
Gas-fired hot air heaters (e.g., industrial burners) can generate higher temperatures, often exceeding 1,093°C. These heaters are used in applications requiring high heat output, such as industrial furnaces and kilns, and for heat-treating metal.
Infrared Heaters
Infrared heaters emit electromagnetic radiation in the infrared spectrum, and their heat range will depend on their design. They are commonly used for drying, curing, and heating surfaces. Some infrared heaters can reach temperatures above 982°C.
Hot Air Generators
Hot air generators are typically used in space heating and forced convection drying processes. Depending on their design, hot air generators can use combustion or electric heating elements to generate hot air ranging in temperature from 93°C to 649°C.
Process Air Heaters
These highly specialised heaters can be designed to reach extremely high temperatures, often exceeding 1,093°C. Process heaters are used in refining, metallurgy, and chemical processing industries.
Secomak’s Offerings: Excellence in excess of 400°C
Secomak’s hot air industrial heaters and fans offer rapid warm-up and high-volume airflow regulating outlet temperatures of up to 400°C. This makes them the ideal option for many processes and applications.
- Power: Secomak industrial fans and heaters range from 1kW to 36kW.
- Maximum Inlet Temperature: Varied. For example, our standard range of industrial heaters have varied max inlet temperatures up to 120°C. However, with an understanding of the application’s setup, we can design and achieve higher inlet temperature tolerances.
- Maximum Exhaust Temperature: All Secomak’s industrial heaters have a maximum exhaust temperature of 300°C. However, through specialised setup, they can maintain output temperatures in excess of 400°C.
- Maximum Airflow: The maximum airflow of Secomak’s heaters varies between ranges. For example, our smallest heater (571/1) has a maximum airflow of 225m3/hr. In contrast, our larger heaters (e.g., 688/36) have a maximum airflow of 2,378m3/hr.
Pushing Boundaries: Ceramic Element Heaters
Advanced industrial heaters using high-grade ceramic elements can achieve temperatures up to 800°C. These heaters are known for their efficiency, durability, and precise temperature control. Below are some of their characteristics and benefits:
- Ceramic heating elements: As their name suggests, these heaters employ ceramic as the core heating element. High-grade ceramics offer excellent heat resistance, thermal conductivity, and insulation properties. Common materials used in ceramic heating elements include Silicon carbide (SiC) and aluminium oxide (Al2O3).
- Versatility: These heaters can be used in a variety of industrial applications. For example, they can be used as space heaters, industrial furnaces, automotive applications (e.g., catalytic converters), and food-processing equipment.
- Efficiency: Ceramic heaters boast high efficiency as they can quickly heat up and cool down. Their rapid response time allows them to reach desired process temperatures faster than most other heating technologies. This efficiency helps to save costs and reduce environmental impact.
- Precision in temperature control: Ceramic heaters offer precise temperature control, making them ideal for high-heat applications requiring specific temperatures. For this reason, these heaters are often used in applications such as semiconductor and medical equipment manufacturing and laboratory settings.
- Durability and longevity: High-grade ceramics are resistant to thermal shock, making them suitable for harsh environments. For example, these robust elements can withstand extreme temperature fluctuations without cracking or degrading.
- Safety and environmental considerations: Ceramic elements are non-toxic and do not emit harmful odours or fumes when heated. This makes them ideal for use in environments where air quality is a concern. Additionally, their durability and longevity help to reduce waste.
While ceramic heaters may boast high temperature capabilities, Secomak’s products have a broad range of power options from 1kW to 36kW, with the ability to regulate outlet temperatures even when dealing with varying inlet allowing customers to choose the perfect fit for their specific needs without over-investing in unnecessary capacity. This ensures energy-efficient operations tailored to individual requirements.
The Intricacies of Recirculating Hot Air
A way to achieve higher heat output in hot air process heaters is to recirculate hot air back into the heater. However, this involves a complex equipment system and considerations to ensure efficiency, safety, and cost-effectiveness.
Here is an overview of the intricacies and factors required when recirculating hot air:
- Heat source: As previously discussed, the type of industrial heater will depend on the process. Typically, industrial heaters are gas burners, electric heaters, or steam coils.
- Air handling units (AHUs): AHUs distribute and circulate hot air within an industrial facility. These units usually consist of fans, filters, dampers, and coils. AHUs should be adequately sized and maintained to ensure efficient heat transfer and air distribution.
- Ducts for distributing hot air: The ductwork and distribution system must be designed to heat the facility evenly. Their design and layout should consider airflow rates, insulation, and outlet placement.
- Temperature control: Most industrial processes require precise temperature control for manufacturing. As such, advanced control systems are necessary to maintain the desired temperature within tight tolerances.
- Heat recovery: Heat recovery systems can be integrated into the hot air recirculation process to improve energy efficiency. Such systems capture waste heat from various functions within the application and reuse it to preheat incoming air (or water).
- Air filtration: Given the recirculated air might be contaminated from the various processes, it must pass through a filtration system to remove dust and particles. This helps to maintain air quality and prevent equipment from fouling.
- Safety measures and maintenance: Industrial hot air systems must comply with strict safety standards to prevent fires, gas leaks, and overheating. As such, installing emergency shutdown and gas detection systems is necessary. Additionally, the system should be regularly checked, cleaned, and maintained.
The Genius Behind Secomak’s Blower Design
Secomak has created an ingenious solution to recirculate hot air using its unique blowers. These direct-drive blowers recirculate hot air back into the air heater’s inlet to heat it higher than the original output temperature.
Usually, blowers that recirculate hot air must be equipped with higher-grade bearings and a cooling mechanism for the motor. However, Secomak’s range of hot air direct drive blowers for recirculating air are designed differently.
The blower’s motor is stepped off from the inlet to the fan and equipped with a cooling impeller on the motor shaft. This design draws fresh and cool air onto the motor shaft to prevent the motor from overheating.
The Significance of Recirculating Hot Air in Heat Packs
One of the most notable advantages that set Secomak’s heat packs apart from others in the industry is the capability to recirculate hot air efficiently. Not only does this advanced feature reduce the overall operational costs, but it also plays a pivotal role in ensuring optimal heat utilisation and energy conservation.
By recycling and reusing the hot air, the need for the heater to run constantly is minimised, leading to reduced wear and tear on the equipment. Furthermore, this approach has decreased energy consumption by up to a staggering 80%. The reason? When you recirculate the already heated air, the heater doesn’t have to work as hard or as often. This equates to substantial energy savings, both from an environmental standpoint and in terms of operational costs.
To ensure precise temperature regulation, our heat packs are equipped with advanced PID temperature controls. These sophisticated controls help operate the heater judiciously, only kicking in when necessary, enhancing the equipment’s lifespan.
The Innovations Behind Hot Air Recirculation
Our dedication to innovation is evident in the meticulous design features we’ve integrated to facilitate hot air recirculation. In our belt-driven fans, we incorporate high-temperature bearings that can withstand the intense heat during recirculation.
For our direct-drive fans, we’ve adopted a unique “stand-off” design. This design entails a slight separation of the motor from the main fan chamber and impellor. With an extended motor shaft, we’ve added a cooling impeller specifically engineered to draw in fresh, unheated air. This cooling mechanism is crucial in preventing heat transfer from the airflow to the motor, thereby averting potential overheating. Without such an innovative design, the motor shaft could easily absorb heat, leading to accelerated wear and potential equipment failure.
In essence, our commitment to maximising efficiency through hot air recirculation doesn’t just benefit the bottom line; it showcases our dedication to pioneering sustainable and energy-efficient solutions in the industrial heating sector.
Conclusion
Hot air heating technology has advanced tremendously since its inception. Industry demands require hot air solutions that offer precision, efficiency, and safety while reducing operating costs and environmental impact. This is why Secomak continues to push the envelope regarding the design and functionality of its hot air systems, creating the perfect solution for industrial processes.
