Unsere Kompetenzen

Foto: Manuel Gutjahr

WG Thermochemical conversion

The objective of thermochemical conversion group activity is to explore and optimize the hydrothermal carbonization (HTC), hydrothermal humification (HTH), and pyrolysis processes for the production of hydrochar, humic substances, and pyrochar. The focus will be on the application of these materials for soil amendment, including increasing water retention, cation and anion exchange capacity, and long-term carbon storage. Additionally, the group will investigate the adsorption of nutrients and pollutants from water, soil, and animal manure, as well as the purification of carbonous materials for advanced applications such as membrane and energy storage. The modeling and optimization help to scale up the processes and transition from batch to continuous processes.

Hydrothermal Carbonization (HTC) and Humification (HTH)

HTC is conducted at elevated temperatures typically ranging from 180 to 250 degrees Celsius, represents an environmentally friendly technology for converting wet residues into hydrochar. Hydrochar finds applications in soil improvement, environmental remediation, biofuel production, and energy storage.

HTH accelerates the production of humic compounds from biomass—a complex process that typically takes years in nature—and accomplishes it within a few hours, delivering significant advantages for soil enhancement. The products are primarily used in agriculture, soil enhancement, and various environmental applications.


 

Batch and Continuous Hydrothermal Reactors

Available hydrothermal equipment includes high pressure batch reactors (150 mL, 1 L, 18.75 L) as well as a continuous reactor from Artec. Further details on post-processing steps can be found in Biochar laboratory.


 

Pyrolysis Process

Pyrolysis is a thermal decomposition process that takes place in the absence of oxygen. It entails exposing carbon-rich materials, such as biomass or organic waste, to elevated temperatures, typically ranging from 300 to 800 degrees Celsius. One of the key outcomes of pyrolysis is the conversion of dry carbonaceous materials into stable forms of carbon known as pyrochar. This pyrochar has a wide range of applications, including its use in soil improvement, biofuel production, and various environmental applications. Furthermore, pyrochar can be engineered or activated to enhance its properties, making it suitable for catalysis, adsorption processes, and energy storage.


 

Pyrolysis Reactors

Pyrolysis (batch and contnious)

Available pyrolysis equipment includes batch pyrolysis muffle furnaces and continuous reactors, including a rotary kiln, a carbon twister, as well as a pyrolysis unit from BIOMACON. Further details on post-processing steps of pyrochar can be found in Biochar laboratory.


Group activities:

1- Process understanding and scale up (Modeling and optimization)

Development of empirical and thermo-chemical models that enable a deeper understanding of complex reactions is a crucial step to scale up the thermochemical conversion processes. This progress extends to kinetic modeling, particularly in the fields of hydrothermal carbonization (HTC) and hydrothermal humification (HTH), where predictive models are enhancing our ability to optimize these processes. Moreover, the integration of intelligent modeling techniques is transforming process optimization, allowing for more efficient and sustainable production methods. These models, helps to predict the system and transitions from traditional batch processes to continuous operations, promising increased efficiency, reduced waste.

  • Development of empirical and thermo-chemical models.
  • Kinetic modeling of HTC and HTH.
  • Intelligent modeling for process optimization.
  • Transitioning from batch to continuous processes.

 

2- Production of engineered pyrochar and hydrochar for different applications

a) Soil Amendment and Carbon Storage:

  • Investigating the interaction of carbon-rich substances with soil and plants.
  • Developing porous pyrochar particles for soil improvement.
  • Producing engineered pyrochar with high carbon sequestration efficiency.
  • Evaluating the potential for carbon-rich materials to act as carbon sinks.
     

b) Nutrient recovery and pollutant removal:

  • Surface modification and functionalization of hydrochar and pyrochar.
  • Engineering of pyrochar and hydrochar for selective nutrient and pollutant adsorption.
  • Studying adsorption capacity for nutrients and pollutants in water, soil, and manure.
  • Exploring applications for water and soil remediation.
     

c) Purification of carbonous materials and advanced applications:

  • Purification and doping of carbonous materials for advanced applications like membrane technology and catalysis.
  • Developing customized char particles for specific applications.
  • Regeneration and reuse of spent carbon-based materials.
  • Removal of pollutants, including PAHs and inorganic elements, from carbonous materials.
     

3- Integrated residue management:

Under integrated residue management program area, the group aims to use the organic waste and residues produced in other processes, and convert it to a more stable form of carbon. The resulted products, based on their characteristics, can be recycled back to the process they are originated from, to increase the yield, and or purification of the products. The products can be applied to other purposes, such as biofuel production, soil and environmental applications.
 

4- Collaboration with industry

Our group's activities extend beyond research as we actively engage in close collaboration with our industrial partners. We are dedicated to addressing their specific needs, offering support in areas such as process development, product characterization, process optimization, and scaling up. This collaborative approach ensures that our research not only advances scientific knowledge but also directly contributes to real-world applications and the success of our industry partners.
 

5- Characterization and analysis of thermochemical conversion products:

  • Elemental analysis, ICP-OES, and nutrient content (P and N)
  • Analysis of gaseous products of pyrolysis and HTC processes
  • HPLC for organic acids, aromatics, and sugars in solid and liquid products
  • Extraction and analysis of humic compounds
  • Characterization through FTIR, BET surface area, pore size analysis, TGA, SEM-EDX
     

Gruppenleitung

Dr. rer.agr. Hoffmann, Thomas

Head of the department System Process Engineering


Department: System Process Engineering

Email: THoffmann@spam.atb-potsdam.de

zum Profil

Mitarbeiter*innen der AG

Postdocs:
Dr. Thomas Heinrich

Internal PhD students:
Huyen Chau Dang
Nader Marzban

External PhD students:
Daniela Moloeznik Paniagua
Saman Ghobadian

Guest Scientists:
Prof. Dr. Fabiano Bisinella Scheufele
Prof. Dr. Caroline Ribeiro

Technicians
Marcus Fischer
Imke Handke