In the Push2heat project, a major step forward in industrial energy efficiency is being demonstrated at Cartiere di Guarcino, an Italian paper mill. This site hosts a pioneering demonstration of steam generation using an Absorption Heat Transformer (AHT) — a cutting-edge technology that upgrades low-grade waste heat into upgraded heat at a higher temperature level.
Part of Demo 3 of the Push2heat project, the system combines an AHT with an external Steam Generation Module (SGM). The AHT harnesses residual heat from the mill’s existing cogeneration plant — around 90 °C — and upgrades it to produce steam at 5.5 barg, using a thermocompressor to boost pressure. The low-temperature heat rejection is managed via river water at around 15 °C, ensuring a sustainable and efficient process.
The installation was completed in July 2025, with commissioning beginning in September 2025. The process started with cold commissioning — verifying all connections, sensors, and control systems — followed by hot commissioning, where the AHT was activated using available waste heat and cooling water. Initially, low-pressure steam was generated only in the flash tank, allowing engineers to confirm stable operation of the upgraded heat water flow and steam production. Later, the full system was tested, including the thermocompressor, to reach the target medium-pressure steam conditions.
A key milestone was the injection of the generated steam into the mill’s existing medium-pressure steam network. This step confirmed the system’s ability to integrate seamlessly with the plant’s infrastructure, ensuring safe, reliable, and efficient operation under real-world conditions.
As part of the PUSH2HEAT project, this demonstration provides valuable insights into the practical integration of heat upgrade technologies in the paper industry, paving the way for wider adoption across energy-intensive sectors.