Environmental Biotechnology and Bioprocess Engineering

Focus

The activities of the Environmental Biotechnology and Bioprocess Engineering Department are focused on the development of processes to convert organic raw materials, residuals and waste products into bulk chemicals, valuable compounds and sources of energy. These processes are often coupled with the recovery of inorganic substances for reuse as fertilizers and the treatment of the water arising from bioconversion, where it serves as a solvent. We generally use anaerobic methods to treat organic residuals such as biodegradable waste or sewage sludge, as these allow commercially viable generation of biogas as a regenerative source of energy. The use of specific anaerobic microorganisms also enables new approaches in communal and industrial wastewater purification, as well as the realization of innovative semi-decentralized prototype wastewater treatment plants. The retention or immobilization of biocatalysts plays a key role here, and we leverage our expertise in this area extensively – both in researching biological surface reactions (biocorrosion, biofilm formation, biomineralization, biofouling, biosensors, and bioleaching) and in the testing of antimicrobial technical equipment. An additional – aquatic – source of raw material we use is microalgae. Natural and sustainable, algae provide a large number of basic chemical materials and an easily digestible biomass.

Competences

The core competence of the department is developing robust biotechnological processes for the production of basic chemicals, which may either be used as raw materials or as sources of energy (methane, ethanol and methanol). In this context “robust” means processes that are resistant to contamination and thus can be operated continuously under aseptic (non-sterile) conditions. Processes are designed exclusively on the basis of microbiological parameters, such as the growth and degradation kinetics of the different organisms concerned. Our engineering activities extend from the planning, commissioning and optimization of laboratory and pilot plants to the planning, construction, commissioning and optimization of innovative demonstration plants in cooperation with our industrial partners. Intelligent combination of the unit operations of mechanical and chemical process engineering (including downstream processing) with bioprocesses using modeling and simulation methods gives us a unique selling proposition, as does our expertise in the targeted colonization and depletion of microorganisms on surfaces.

  • Both classic and “continuous” high-throughput screening methods for autochthonic production strains as high potentials for robust processes or new product lines
  • Batch, fed-batch, and continuous fermentation processes, including those involving partial or total cell retention
  • Cultivation of microalgae in photobioreactors
  • Microbiological characterization of surfaces using standard processes and application-oriented processes, including development of test procedures
  • Psychrophilic, mesophilic, and thermophilic bioprocesses
  • Development of real-time processes for monitoring water systems for contamination
  • Modeling of processes and simulation of process lines
  • Scale-up of processes and scale-down of unstable process states to solve problems during technical operation
  • Downstream processing technologies such as membrane-based filtration processes, liquid-liquid extraction, and extraction with supercritical media
  • Integrated models for management of energy, waste and water

The use of anaerobic biocatalysts to produce bulk chemicals or energy carriers has the advantage of a 90 percent carbon-source-to-product yield. The use of rapidly growing photoautotrophic cells (microalgae) also leads to comparatively higher productivities than is achievable with terrestrial plants. Further benefits are reduced water requirements and the feasibility of water-based production of algae.

The Environmental Biotechnology and Bioprocess Engineering Department is thus in a position to take part in solving socio-political challenges such as the greenhouse effect, energy supply and freshwater shortage. By offering sustainable technology options, the department can help industry, communities and policymakers design a balanced future. Combining our competences with those of other Fraunhofer IGB departments, we serve the needs of the chemical, energy and environmental business areas.