Technology company Voith has deployed its SteamBooster heat recovery system at Koehler Paper’s Kehl mill in Germany, enabling the specialty paper manufacturer to recover waste heat from production and reduce carbon emissions by up to 1,500 tonnes annually.
The SteamBooster system, operational since June 2025, is part of a three-stage heat recovery concept designed to lower the mill’s natural gas consumption by converting high-temperature exhaust air into usable process steam.
Installed on the offline coating machine SM 8, the SteamBooster captures exhaust heat generated by Voith’s non-contact MCB dryers, where temperatures can reach 300°C. Instead of allowing this energy to dissipate, the system transfers the heat through a heat exchanger to produce steam from condensate, which is then fed back into the production process.
The installation generates approximately one tonne of steam per hour, reducing the load on the mill’s boilers while lowering energy costs.
Originally developed and patented for tissue hood applications, Voith has expanded the SteamBooster’s use to a wider range of paper machines with exhaust-air temperatures exceeding 100°C, including hot-air dryers and vacuum blowers.
The company said the turnkey system can typically recover one to five tonnes of steam per hour, depending on the mill’s configuration and can be retrofitted during routine maintenance shutdowns. According to Voith, most paper mills can expect a payback period of less than two years.
The Kehl project reflects the long-standing collaboration between Voith and Koehler Paper to improve energy efficiency across specialty paper production.
As paper manufacturers face increasing pressure to decarbonise energy-intensive operations, Voith has expanded its portfolio of heat recovery systems, heat electrification technologies, digital solutions and related services aimed at reducing both energy consumption and emissions.
Dr Mario Vollmer, Innovation Manager Energy at Koehler Group, said the installation was completed quickly and delivered meaningful energy efficiency gains for the mill.
Voith’s Martin Dauner, Product Manager Steam & Condensate at Voith Paper, described SteamBooster as a “low-risk, high-reward” solution that can be tailored to individual mill conditions while offering straightforward installation during scheduled maintenance periods.
