Within industrial processes, temperature control is essential to guarantee product quality, energy efficiency, and worker safety. However, the equipment can often leak heat, causing significant energy losses.
In addition, heat leaks can increase production costs, shorten equipment life, and pose a risk to worker safety and the environment. Therefore, having processes to detect possible failures and employing effective thermal insulation systems are essential elements for achieving the best possible operation.
This article delves into what heat leaks are, what types exist, and how you can address them in your industrial processes.
What are heat leaks, and why are they problematic in industrial processes?
Heat leakage is the release of thermal energy from an industrial system or process to its surroundings. This can be caused by factors such as:
- Lack of adequate thermal insulation.
- The presence of a fault in the insulating material.
- Reducing atmospheres.
- Other elements that can affect the process, such as corrosion and mechanical wear.
So, we might find them occurring in various pieces of equipment and industrial processes, such as boilers, pipes, tanks, furnaces, kilns, etc. They can also weaken an operation’s energy efficiency levels - as well as adversely affecting equipment, worker and environmental safety.
Having adequate thermal insulation can prevent or significantly reduce heat leakage, allowing for better temperature control and reduced energy costs.
Causes of heat leakage
When the heat generated in a process is transferred to the surrounding environment instead of being used for other purposes, there is heat leakage.
However, once identified, it is advisable to determine the causes of it. Although these may vary according to the context, we present the most frequent:
This is known as collateral damage present in the work environment. It typically occurs when the insulation receives some sort of impact during a charge and discharge process.
This type of damage can also occur in situations where poor maintenance practices have occurred, with insufficient care given to protection of the materials, consequently giving rise to the creation of cracks, fractures, or damage to the insulation, which leads to heat leakage.
Mistakes during the insulation system installation
Leaving unsealed seams, knocking into insulation during installation, or failing to ensure proper compression of insulating materials can generate heat leaks. For this reason, it is vital to have an engineering team with the necessary experience to guide you in the thermal insulation installation process.
Likewise, you must be able to provide as much information as possible about your process to the engineering team that will be undertaking your insulation installation project.
Insulating materials are frequently exposed to reducing conditions that harm the ceramic fiber. That is, reducing atmospheres can decrease the thermal qualities of the material or alter the process (for example, hydrogen saturation can increase the thermal conductivity, which may require a reassessment of the insulation system).
Insulation life cycle
Insulation systems tend to degrade over time due to their continuous shrinking process during use or the incidence of factors such as airspeed (causing erosion).
How to identify heat leaks
Some steps that can be followed to identify heat leaks in industrial processes are:
- Carry out a visual inspection of the insulation conditions. Although it is impossible to observe heat directly, its effects can be felt. Therefore, it is advisable to pay attention to high-temperature areas in the equipment, such as pipes and valves. It is also possible to observe the presence of stains or corrosion in the insulating material, as well as noticeable deformations in the insulated equipment.
- Inspection with a thermographic camera. This type of camera can identify areas with high temperatures that are not perceptible to the naked eye. They detect the infrared radiation emitted by objects and convert it into a thermal image that shows hot spots.
- Take temperature measurements. Thermometers (contact or non-contact) can be used to measure the temperature of different parts of the equipment and/or piping. Elevated temperature areas may be indicative of heat leaks.
- Inspect the insulation system. This can become damaged over time and be the cause of heat leaks. Inspecting the insulation helps identify areas where damage exists and the insulation needs replacement or repair.
- Perform an energy analysis. Identifying the process areas where energy is lost and facilitating decision-making to improve efficiency is recommended.
In addition, it is essential to consider routine insulation wear, since it is subject to factors such as erosion caused by the airflow in the process, mechanical wear, or some reducing atmosphere.