Heat and Sorption Systems

Efficient usage of energy in times of climate change and decreasing fossil resources is one of the big challenges we face today, and is thus a key field of activities at the group “heat and sorption systems”. One of our basic goals is to increase energy efficiency by applying and combining energy saving or process intensifying technologies. Concerning process technology, efficient application of energy can particularly be realized by technologies such as drying with superheated steam or the application of electromagnetic fields for volumetric heating.

Besides process intensification and the energy efficient design of industrial processes, the efficient usage of renewable energies and the possibility of energy storage are fundamental parts to ensure sustainable usage of energy. Vast amounts of waste heat are produced during many common industrial processes – the utilization of the waste heat provides an enormous potential in terms of cost and energy savings and process optimization. Key topics are the development, realization and optimization of innovative concepts for the thermal treatment of water and other substances, sorptive heat storage, solar desalination of seawater, concentration of industrial waste water and water harvesting from air humidity by a sorption process. For research, development and process applications on behalf of industrial clients, we operate with both stationary and mobile equipment. In addition, equipment for analytics and powerful software tools for simulation and design of prototypes are also available.

Fields of research

 

Sorptive Heat Storage

Systems enabling long-term storage of waste or surplus heat without losses are essential for the design of energy efficient processes and energy systems. Meeting the challenge to increase storage capacity, efficiency and flexibility by means of storage duration and space available we develop novel approaches by means of ab- and adsorptive heat storage systems.
 

Thermal Separation Processes

For the treatment of industrial process water as well as applications as seawater desalination, our multistage vacuum evaporation process ensures savings by the efficient use of heat at low temperatures. In our approach neither vacuum- nor vacuum jet pumps are required for generating the vacuum.

 

Sorptive Dehumidification

Sorptive dehumidification consists of two stages: first, the air humidity is absorbed by a highly concentrated hygroscopic saline solution and thus bound; then second, this diluted saline solution is distilled and the water separated is condensed. Water harvesting from air humidity is one exemplary application of sorptive dehumidification.
 

Drying with Superheated Steam

Drying is an essential process step in various branches of industry. Using superheated steam as drying medium can provide significant advantages in terms of retention time, energy consumption and further aspects such as product quality. A further advantage is that valuable volatile compounds can be recovered selectively from the condensate to be recycled or further processed.

 

Torrefaction of Lignocellulosic Biomass

For the improved energetic and material use of lignocellulose-containing biomass, we have successfully demonstrated torrefaction up to pilot scale. The torrefied biomass is water-repellent and can be transported as open bulk material. The volatile substances produced during torrefaction can also be used to produce chemicals that serve as starting materials for many other industrial products.