Research and development for the generation of carbonization and biochar

Fraunhofer UMSICHT develops plants and processes for the carbonization of biomass and biogenic waste and residual materials at the Sulzbach-Rosenberg site. For our partners, we offer scientific support along the entire value chain from the feedstock to the production and application of biochar and carbonates.

© Fraunhofer UMSICHT
From biogenic feedstock to product: Fraunhofer UMSICHT accompanies along the entire value chain of plant carbon production

Carbonates as CO2 sinks and substitutes for fossil fuels

Reactor system for the carbonization of biogenic residues into biochar at Fraunhofer UMSICHT

According to the IPCC, additional measures are needed to actively remove CO2 from the atmosphere (carbon dioxide removal) in order to limit global warming to 1.5 degrees. 

The carbonization of biomass using PyCCS (pyrogenic carbon capture and storage) is considered a reliable technical approach.

It consists of using thermochemical processes to convert plants that have previously fixed CO2 through photosynthesis into biochar / carbonisates.

The carbon bound in the carbonisates can be stored effectively and safely over long periods of time. Biomass carbonisates, which are used as a substitute for fossil coals, are considered climate-neutral and can reduce the CO2 footprint of processes and products.

Overview service spectrum

© Fraunhofer UMSICHT

Characterization and testing of input materials

  • Testing the suitability of feedstocks for carbonisate production on our own thermochemical conversion plants, in particular pyrolysis reactors
  • Support in the selection of available biomasses / biogenic residues for the production of biochar
  • Database with over 70 tested feedstocks

Process and plant development

  • Development, design and prototype construction of own and external carbonation / pyrolysis plants
  • Support during plant design, commissioning and scale-up
  • Advice on the utilization and treatment of any secondary products (gas, oil, process water) that may be generated.
  • Support for technology integration into existing processes
  • Test campaigns and optimization of plants in our own pilot plant or externally

Analysis and application optimization of carbonisates / biochar

  • Analysis and quality assessment of carbonates
  • Preparation and refinement of carbonates into products with specific properties based on defined parameters
  • Evaluation and selection of suitable vegetable carbons for a specific application
  • Preliminary tests / pre-analytics for certification processes of biochar

Technical and economic evaluation of carbonation processes

  • Technical evaluation and advice on the selection of carbonate manufacturing processes and equipment
  • Potential studies and economic feasibility studies

Fraunhofer's own research facilities for carbonization

© Fraunhofer UMSICHT
Carbonisates from fermentation residues
© Waste Biomass as Alternative Bio-Fuel – Co-Fireing versus Direct Combustion, 2007
Carbonisates produced by the TCR process (bottom left) have low acid and hydrogen contents.

Fraunhofer UMSICHT in Sulzbach-Rosenberg has many years of experience in the production and analysis of carbonisates (especially vegetable carbons) from a wide variety of biogenic and non-biogenic feedstocks.

The institute section has various pyrolysis plants for the carbonization of biomasses from laboratory to industrial scale with throughputs of 2, 10, 30 and 500 kg. In test campaigns, large quantities of feedstock can thus also be put through and corresponding product quantities can be generated.

The thermo-catalytic reforming process developed at the institute deserves special mention. This pyrolysis-based technology achieves an upgrading of the carbonisates produced in the pyrolysis process through a downstream reforming step. The high product quality allows high-value applications of the carbonisates that are not possible, for example, by conventional (flash) pyrolysis processes or hydrothermal processes such as hydro- and vapothermal carbonization. Carbonisates produced by TCR processes have low acid and hydrogen contents and high stability in soil applications. 

In addition to carbonization technologies, various gasifier test beds are available that are optimized for biochar.

© Fraunhofer UMSICHT
Research reactor for carbonisate production with 2 kg throughput / h
© Fraunhofer UMSICHT
Large-scale demonstration plant for the production of carbonates up to 250 kg / h
© Fraunhofer UMSICHT
Fixed bed reactor test rig for biochar.

Pretreatment, analysis and preparation of carbonates

Appropriate research and laboratory infrastructure is available for the conditioning of feedstocks, analysis, and processing of the vegetable coals, including by-products and downstream products.

Conditioning of feedstocks / sample preparation Characterization / Analytics Preparation / Refinement
Pelletizing, grinding, drying Chemical parameters (water content and water extractable substances, ash content, PAH, metals, calorific and heating value, CHNO) Briquetting, pressing
  Physical parameters (bulk density, jolt density, density via helium pycnometer, particle size distribution, pressure drop, impact hardness, rolling abrasion hardness, ball-pan hardness, Hg porosimetry).  

Adsorption parameter

Iodine number

BET (N2, CO2, Ar, Kr)


Application areas for biochar

© Fraunhofer UMSICHT

Depending on the area of application, vegetable carbons must fulfill specific properties. Fraunhofer UMSICHT provides support in the preparation and refinement of carbonates into products with defined parameters.

Soil applications

Vegetable carbons can find application in the agricultural context with the aim of carbon storage or soil improvement. Depending on the purpose, the physical and chemical properties of the respective vegetable carbon, compliance with limit values in accordance with international guidelines and appropriate certification are important for such an application.

Building and materials

As a filler in concrete, asphalt or plastics to reduce the CO2 footprint of the products or to specifically modify the product properties.  Porosity, particle size distribution, adhesion behavior and leaching behavior of pollutants play a major role here. These properties can be modified by targeted processing. We offer various processes for this purpose.  


Coal from fossil sources is an important input material in industry, e.g. in the sintering plant for the production of iron ore agglomerates, in the electric arc furnace as injection or feed coal, or as alloying coal for adjusting the carbon content of the steel. To achieve CO2-neutral steel production, the replacement of fossil coals by vegetable coals plays a major role. Decisive parameters for this are the ash content, the amount of volatile components, the calorific value, the particle size and the reactivity. The selection of suitable feedstocks as well as the process parameters during the conversion of biomass to produce the vegetable carbon is therefore crucial.

Thermal utilization

Whether for combustion or gasification of the plant carbon for the generation of process heat or electricity, the calorific value, the proportion of carbon or the ash content is decisive. Together with you, we evaluate the suitability and, if necessary, optimization of the resulting carbonisates for efficient thermal utilization.  

Recovery of recyclable materials

Biomass and biogenic residues partly contain valuable nutrients such as nitrogen, phosphorus or potassium. In the context of landfilling, these are lost for targeted application. By means of pyrolytic conversion, these nutrients can be recovered from the input materials in a targeted manner, either from the plant carbon itself or from the existing side streams (gas, oil, water), and used further in a targeted manner.

Carbonisates as CO2 sinks and substitutes for fossil coals

According to the IPCC, in order to limit average global warming to 1.5 degrees, complementary measures are needed to actively remove CO2 from the atmosphere (carbon dioxide removal). PyCCS (pyrogenic carbon capture and storage) is considered a reliable technical approach. It consists of using thermochemical processes to convert plants that have previously fixed CO2 through photosynthesis into plant carbon / carbonisates. The carbon bound in the carbonisates can be stored effectively and safely over long periods of time. Biomass carbonisates used as a substitute for fossil coals are considered climate neutral and can reduce the CO2 footprint of processes and products.

Sample projects


UMSICHT uses plant carbon from pyrolysis processes to upgrade soils

Project InterPyro


EU project


A global approach to reclaiming agricultural land through a combination of phytoremediation, biofuel production and climate-friendly copper smelting.


EU project


Fraunhofer UMSICHT is responsible for implementing the German pilot project for nutrient recovery from cattle manure. The innovative process chain will maximise nitrogen recovery and phosphorus utilisation from cattle manure and convert it into the commodity fertiliser ammonium phosphate. In addition, phosphorus-rich biochar will be produced.

Terminology: Biochar - plant carbon - (biomass) carbonisate.

The treatment of biomasses by means of a thermal process (technical pyrolysis or hydrothermal carbonization) leads to an increase in the relative carbon content. The resulting products are generally referred to as carbonisates; depending on the feedstock, the term biochar or vegetable carbon is also commonly used. However, to distinguish it from coal from fossil sources, the term »biomass carbonisate« is preferred.

Carbon carriers that can be used and applied directly as a material in agriculture or animal husbandry are defined as vegetable carbon. Only unpolluted biomasses are used in their production.

If pyrolysis is carried out as a thermal treatment process to obtain the carbonisates, the resulting products are called pyrolysis charcoal (or pyrolysis coke). With woody feedstocks and slow heating rates in the pyrolysis process, the product obtained is charcoal.

The term Terra Preta is also used, for example, in the context of the agricultural use of plant charcoal. This refers to a soil that has been strongly influenced by humans, which is found in the Amazon basin and has particularly fertile properties due to carbonisates from biomass introduced into it.

Further carbonaceous material can be produced by biomass gasification. These products are referred to as gasifier coke. This term can also be used in connection with other products, e.g. fossil products, and is not purely related to products from biomass.