Podcast Con G de Geo: heat recovery and industrial sustainability
At BOIXAC, we had the honor of being invited to participate in the podcast Con G de Geo, which aims to bring engineering closer to development through sustainability, via renewable energy, energy optimization, and efficient use of resources.
Below you will find the transcript with our contribution, and we encourage you to listen to it by clicking here.
1. Introduction
In December 2019, what we know as the European Green Deal was approved, aiming to achieve climate neutrality by 2050. To this end, a roadmap of different actions was established, and one of the milestones where we will stop and assess whether we have done our homework is 2030.
2. The European Green Deal and 2030 targets
In addition to including aspects such as restoring biodiversity, improving animal welfare, or promoting sustainable forest management, there are three aspects that directly influence the energy sector:
All these aspects are important to address the climate emergency but, at BOIXAC, we understand that if the global population continues to grow—only in Spain, for example, a 2% increase is expected over the next 15 years—beyond the use of renewable energy, sustainability requires changes in consumption and resource optimization.
In this sense, considering that Spanish industry consumes around 31% of total energy, its modernization and optimization are key factors for our future.
3. Industry as a lever for change
Spanish industry consumes around 31% of total energy. Its modernization and optimization are key to the country’s energy future.
When we drive on the highway, as far as the eye can see, we observe factories that require energy for their processes. Some examples:
4. Energy balance and heat recovery
All processes that require heating or cooling need energy, and energy maintains a balance. In fact, heat is the transfer of energy from a region of higher temperature to one of lower temperature. For example, if we look at what happens in our homes when we turn on air conditioning, we observe this balance. While the indoor unit supplies cold air, the outdoor unit expels excess heat.
Based on this energy balance, we see that a certain renewal of indoor air is required to maintain its quality. For this renewal, we take outdoor air and cool or heat it depending on the need. At the same time as we introduce fresh air, we must expel stale indoor air to make room for the new air, and this is where heat recovery comes into play.
If we move from our homes to industry and imagine, for example, that outdoor air is at 20 ºC and we want to heat it to 80 ºC indoors—such as in a drying process where moisture extraction is needed—it may seem that we need equipment capable of raising the air temperature by 60 ºC. However, there is a smarter, more economical, and sustainable alternative.
5. How a heat recovery system works
Air at 20 ºC captured from outside that we want to introduce into the process.
Incoming air and outgoing air (at 80 ºC) cross paths without mixing through a cross-flow system.
Heat is extracted from the outgoing air stream and transferred to the incoming air stream while maintaining air quality.
When we take outdoor air at 20 ºC and want to heat it before introducing it into a room, the same airflow that was indoors at 80 ºC will be expelled. Through a heat recovery system, these two airflows cross without mixing. We do not mix them in order to maintain air quality, but we do transfer heat from the outgoing air to the incoming air.
With this system we achieve two objectives:
The cold air entering increases its temperature, reducing the load on heating systems such as boilers, saving energy and improving sustainability.
The hot air being expelled lowers its temperature closer to ambient levels, further improving sustainability.
Heat recovery technology varies depending on application and manufacturer, but it is based on improved filtration, efficient fans, and energy recovery cores that enable heat exchange. Additional features may include control systems or insulation.
6. BOIXAC and industrial heat exchangers
At BOIXAC, we specialize in industrial heat exchangers, developing solutions for corrosive environments, high pressures, and temperatures up to 950 ºC, achieving efficiencies above 80%.
Each industrial application is unique, so every project is carefully studied to optimize efficiency, sustainability, and cost savings.