Process plants often vent 90 °C water, once considered too low for recovery. However, Kaltra microchannel heat exchangers now extract 250 kW of heat from that stream. Consequently, the recovered energy heats makeup water to 70 °C, reducing boiler gas use by 18%.
The secret lies in a flat multi-port aluminum core. It offers 1,500 m² of internal surface per cubic meter. Therefore, this design boosts heat-transfer coefficients above 5 kW m⁻² K⁻¹ — and does so without any copper.
Each tube holds 20 to 90 ports, each only 0.7 mm wide. These narrow channels force turbulent flow even at Reynolds numbers as low as 400. As a result, the exchanger delivers the same capacity with 45% less face area and 40% lower internal volume than traditional shell-and-tube models.
In addition, its compact design saves valuable floor space and allows for future plant expansion.
Single-Block Aluminum Core Rated 30 Bar, 200 °C, 650 h Salt-Spray
Kaltra vacuum-brazes every joint at 600 °C under nitrogen, creating a monolithic block rated for 30 bar working pressure and 200 °C continuous temperature. The all-aluminum body survives 650 h neutral salt-spray without pitting, giving microchannel heat exchangers a 20-year design life in coastal or urban atmospheres without protective coatings. Weight drops by 200 kg per 500 kW section, allowing existing pipe racks and foundation bolts to remain unchanged.
Thanks to this durability, the heat exchangers achieve a 20-year design life, even in coastal or urban conditions. Furthermore, each 500 kW section weighs 200 kg less than comparable exchangers, allowing existing pipe racks and foundation bolts to remain in place.
Optional Fin Coating for Harsh Sites
Fin spacing ranges from 18 to 30 FPI. For environments where chloride exceeds 1 mg/m³, a 12 µm cathodic epoxy coating can be applied at the factory. In turn, this layer extends salt-spray life to 2,000 hours while adding only 3 Pa of extra pressure drop.
Therefore, the coating provides long-lasting protection without compromising performance.
AI-Based Sizing Portal
Kaltra’s AI-driven sizing portal makes configuration simple and fast. Users just enter stream data, pressure limits, and footprint size. Then, within one minute, the software delivers an optimized design.
In addition, it calculates effectiveness, pump power, and price with proven accuracy. The exported package also includes STEP files, wiring diagrams, and ERP-ready BOMs. Consequently, engineers can proceed to procurement and design stages without repeating data entry.
High-Capacity Production and Fast Delivery
Kaltra operates advanced facilities in Graz and Plzeň, equipped with fourteen vacuum-brazing furnaces running 24/7. As a result, the company produces over one million cores per year.
Standard lead time is ten working days. However, for urgent needs, emergency batches ship within 72 hours, fully brazed, pressure-tested to 52 bar, and dried to −40 °C dew point.
Sustainability and Energy Savings
By converting low-grade waste heat into usable energy, Kaltra microchannel heat exchangers help plants reduce fuel consumption and CO₂ emissions. As a result, each system upgrade supports both energy efficiency and sustainability goals.
Ultimately, this technology enables industries to meet environmental targets while improving operational performance.
