HEAT RECOVERY
Heat recovery systems are industrial heat exchangers designed to recover and reuse thermal energy contained in hot exhaust gases generated by boilers, furnaces, engines, turbines and industrial thermal processes. Their primary function is to transfer this residual heat to a useful process fluid, significantly improving overall energy efficiency while reducing fuel consumption and associated CO₂ emissions.
BOIXAC heat recovery solutions are engineered for industrial environments where energy efficiency, operational reliability and long-term performance are critical. These systems enable companies to optimize their thermal processes while contributing to sustainability and cost reduction objectives.
OPERATING PRINCIPLE OF HEAT RECOVERY SYSTEMS
A heat recovery system operates by transferring thermal energy from hot exhaust gases to a secondary fluid through a heat exchange surface. The exhaust gases and the process fluid flow through separate circuits, ensuring no cross-contamination while maximizing thermal transfer efficiency.
Depending on the application, the recovered heat can be used to heat:
water
superheated water
thermal oil
steam (in specific configurations)
This process allows energy that would otherwise be discharged through the stack to be reused within the plant, improving overall system efficiency and reducing primary energy demand.
TYPICAL OPERATING CONDITIONS
BOIXAC heat recovery systems are designed to operate reliably under demanding industrial conditions, including:
exhaust and process gases containing dust, particles or residues
high fouling environments
elevated operating temperatures, up to 850°C
fuels such as biomass, natural gas, fuel oil and diesel
Thanks to their robust and modular design, these systems can be precisely adapted to the specific operating parameters of each installation, ensuring stable performance and long service life.
1- Inspection opening. 2- Extraction system. 3- Condensate collection tray. 4- Transition (rectangular to circular)
HEAT RECOVERY AND ENERGY EFFICIENCY IMPROVEMENT
Industrial heat recovery systems are widely implemented in boilers and continuous thermal processes. By capturing heat from exhaust gases before they are released into the atmosphere, they significantly reduce thermal losses.
In a heat recovery unit:
hot gases enter the exchanger at high temperature
thermal energy is transferred through the heat exchange bundle
the process fluid absorbs the recovered heat
cooled gases are discharged at a lower temperature
This results in improved process efficiency, reduced fuel consumption and, in many cases, a rapid return on investment.
DESIGN FEATURES, ACCESSIBILITY AND MAINTENACE
BOIXAC heat recovery systems incorporate design solutions that simplify inspection, cleaning and maintenance, even in harsh industrial environments.
Common design features include:
structures resistant to extreme temperatures
easily accessible inspection openings
removable heat exchange bundles for cleaning
adaptation to existing stacks and ductwork
thermal insulation using rock wool or fire-resistant materials
flow control through bypass systems, dampers and integrated regulation
This design philosophy minimizes downtime, facilitates maintenance operations and ensures high system availability.
HEAT EXCHANGER CONFIGURATIONS
BOIXAC offers a complete range of heat recovery configurations, tailored to the specific requirements of each project, including fluid type, temperature, humidity, pressure and fouling level.
Typical heat exchanger configurations include:
continuous finned tubes: large heat transfer surface and high efficiency
helical finned tubes: increased turbulence and enhanced heat transfer
plain tubes (non-finned): high mechanical strength and fouling tolerance
pillow plate systems: high robustness, low fouling sensitivity and stable performance
This flexibility allows BOIXAC to deliver customized heat recovery solutions that integrate seamlessly into any industrial infrastructure.
Typical ROI
Efficiency
Temperature
Welds
What us a geat recovery system?
A heat recovery system is an industrial heat exchanger that recovers waste heat from hot exhaust gases and transfers it to a useful process fluid.
What is the difference between heat recovery and an economizer?
Heat recovery is a broad concept covering various waste heat reuse solutions, while an economizer is a specific type of heat recovery unit typically associated with industrial boilers.
Which industrial processes benefit most from heat recovery?
Processes that generate hot exhaust gases, such as boilers, furnaces, engines, turbines and industrial drying systems, benefit significantly from heat recovery.
Which fluids can be heated using a heat recovery system?
Common fluids include water, superheated water, thermal oil and, in certain applications, steam.
Can heat recovery systems operate with dirty or particle-laden gases?
Yes. With appropriate design, materials and exchanger configuration, they can operate reliably with gases containing dust, particles or residues.
How demanding is maintenance for a heat recovery unit?
Maintenance requirements are reduced through accessible inspection points, removable exchange bundles and designs optimized for cleaning.
What is the typical payback period for a heat recovery system?
In many industrial installations, the payback period typically ranges from 3 to 12 months, depending on operating conditions and energy recovery potential.
Which are the main industrial applications?
Heat recovery systems are widely used in the following sectors: energy generation, oil and gas, food and beverage industry, marine and offshore installations, industrial thermal processes, material drying systems, industrial boilers, wastewater treatment plants.
What materials are commonly used in the construction of a heat recovery system?
Industrial heat recovery systems can be designed using different materials depending on operating temperature, fluid corrosiveness and process conditions. Commonly used materials include carbon steel, stainless steels AISI 304, AISI 316, AISI 309 and AISI 310, as well as aluminium alloys such as AL5754, AlMg3, Al5052 or AlMg2.5. Proper material selection is essential to ensure durability, operational safety and optimal thermal performance.
Finned tubes heat exchanger
Smooth tubes heat exchanger
Dimple plate heat exchanger