Patent granted for HOF Buffer Tank technology as major innovation for freeze-drying

Lohra, Germany: Leading freeze-drying and pharma process specialist HOF Sonderanlagenbau GmbH has been awarded a patent on its ingenious Buffer Tank technology that offers a solution to emerging sustainability and regulatory problems in lyophilization.

The HOF Buffer Tank has been developed and proven by HOF to enhance the efficiency and sustainability of freeze-drying (lyophilization) processes in the pharmaceutical and biotechnology industries. This technology is now a core component of HOF’s CCU CryoBlizzard technology that uses only air as a natural refrigerant, aligning with stringent environmental regulations and promoting eco-friendly operations.

Solving the F-Gas problem

The patent authorities have recognized the buffer technology as a genuine innovation in thermal technology that complements HOF’s CryoBlizzard air cooling platform in liberating the freeze-drying process from reliance on non-sustainable refrigerants.

Pharma, food processing, and other industries have faced impending problems from stricter regulation on environmentally unfriendly fluorinated greenhouse gases (F-gases) used in refrigeration, freeze-drying, air conditioning, insulation, and other applications — due to their high global warming potential (GWP). These gases include hydrofluorocarbons (HFCs), perfluorocarbons (PFCs) and sulfur hexafluoride (SF₆) that can stay in the atmosphere for hundreds to thousands of years and trap heat thousands of times more effectively than CO₂. Their emissions are rising, especially in sectors like HVAC and pharmaceuticals.

Recent measures such as the EU’s F-Gas Regulation, PFAS, etc. aim for an 80% reduction in HFC use within five years, limiting their use in refrigeration for lyophilization and posing a severe challenge to existing freeze-drying processes.

Thermal Stacking

In response, HOF has developed its CCU CryoBlizzard technology that uses Mirai Intex cold air machines that generate the required refrigeration power by using only air as refrigerant with no polluting effects. The buffer tank (also called the loading tank) is a core component of the CryoBlizzard platform that uses innovative ‘thermal stacking’ to store the heat transfer fluid at different temperature energy layers to supply the different consumers of the system on demand. The coldest heat transfer fluid is used within the ice condenser of a Freeze-Dryer, where deep temperatures are needed, whereas the warmer layer is used within the shelf system of the Freeze-Dryer.

The Buffer Tank enables a Dynamic Load Management approach that decouples refrigeration generation from the consumption side to manage varying thermal loads more efficiently. Matching different cooling energy supply with the particular demands of different consumer units increases total system energy efficiency and reduces overall energy consumption. This flexibility also reduces the need for oversized chillers and minimizes demand during peak periods.

The HOF Buffer Tank Technology is particularly beneficial in batch processes like freeze-drying, where thermal demands fluctuate between freezing, primary drying, and secondary drying phases. By providing a stable and adaptable cooling supply, the system enhances process reliability and product quality.

Proven technology

The technology has been developed by HOF since 2019 and has now been established within in the pharmaceutical industry in many processes, such as a recent project at the leading biotech producer CSL Behring where this technology has been successfully developed and installed by HOF in partnership with sustainable refrigeration specialists Refolution Industriekälte GmbH (see Resources).

Fabian Plaum (Sales Manager at HOF) commented: “The HOF CCU CryoBlizzard with the patented buffer tank technology provides a sustainable and future-proofed solution for customers in order to be independent of regulatory requirements and fulfill global CO2 emission goals.”

“Many customers are not yet aware of our future-proofed technologies and still think that these technologies are unproven prototypes. We are now showing that this is far from the case and that these technologies have been successfully executed multiple times.”

“This patent award not only confirms the technological lead of our solution, but also its sustainable contribution to energy efficiency,” said Mr. Plaum.

About HOF Sonderanlagenbau

HOF Sonderanlagenbau GmbH is a world-class and highly innovative special equipment manufacturer of Freeze-Drying, Freeze-Thaw, and loading/unloading systems for the pharmaceutical and healthcare industries.

Founded in 1988, this German family-owned company has become one of the world’s most respected names for high quality just in time freeze drying (lyophilization) solutions, with more than three decades of experience.

Sonderanlagenbau is German for ‘special equipment manufacture’ and in this case, refers to HOF’s lab scale, pilot scale and production scale freeze drying solutions, loading, and unloading systems, and freeze-thaw units for the pharmaceutical, biotech and life science industries.

From its advanced manufacturing base at Lohra, north of Frankfurt, HOF designs and constructs specifically tailored freeze-drying and associated solutions for companies all over the world under its motto of “Just in time quality for demanding customers.”

HOF Sonderanlagenbau is the leading manufacturer for customized Freeze-Drying solutions and has constructed a fully integrated total design and build environment in which every machine is unique, exactly specified in partnership with customer and manufactured to meet very specific requirements.  The partnership ethos extends into ownership, with our comprehensive service and maintenance offerings designed to ensure that no one needs to work on a HOF machine except its own experts.

HOF is consistently named as one of the Top 100 most innovative companies in Germany.

Learn more at: www.hof-sonderanlagen.de/en/home/.

Resources

Click on HOF innovative green refrigeration technologies for enhanced sustainability to learn more.
Click on CSL Behring – Freeze-Dryer with sustainable refrigeration technology – CryoBlizzard by HOF to see video of recent installation at leading biotech medicines manufacturer.