"Entrained flow gasification with biochar from hydrothermal carbonization for decentralized energy supply of electricity and heating with a Motor-BHKW (Combined heat and power unit)"


In the last few years, the use of biomass for electricity and heat production has moved increasingly into focus. The conversion to energy of biomass is currently often decentralized after the conversion of the biomass into a combustible gas through fermentation, and its utilization in combined heat and power units. However, the entire energy content of the biomass cannot be implemented through this method. In alternative processes, that are used for conventional fuels (coal, for example), technical difficulties brought about by the characteristics of the biomass become a problem. Another problem is the food-competition in the use of energy crops, which presents one of the major points of criticism regarding the use of biomass as an energy source.

The process of hydrothermal carbonization (HTC) is a well known, but only recently rediscovered technology for industrial usage, for the conversion of biogenic waste into biochar. The fuel characteristics of biochar are similar to those of lignite, a fuel that is relatively unproblematic when compared to biomass, which makes its gasification possible. For this process, primarily biogenic waste should be evaluated that has not yet been used for energy generation, such as green waste, thinnings, straw and landscaping materials.


Together with Suncoal Industries GmbH, which is focusing on the HTC-Process, the conversion of biochar in an entrained-flow gasifier will be investigated. Entrained-flow gasification is a robust gasification process, which, with the addition of gasification air, generates a fuel containing carbon monoxide and hydrogen. Due to the characteristics of biochar, gasification can be carried out at temperatures around 1000°C, as well as at low processing periods. The reasons behind this are, among other things, the high ash softening temperature, as well as the small grain size. Through the relatively high gasification temperature, especially when compared to other wood gasification processes (fixed-bed, fluidized bed), the generation of a low-tar fuel gas is ensured.

The purified producer gas generated should be used highly efficiently and decentrally in a Gasmotor-BHKW for power and heat generation, and developed on a scale < 2 MWel. For the investigation of the gasification, the Institute for Energy Systems operates both atmospheric and supercharged pressure entrained-flow gasification facilities in its own technical department.

Work Packages

The research carried out at the IES focuses on the foundational assessment and parameter analyses, using the gasifiers available at the IES.

  • Foundational research on the gasification of biochar using a laboratory entrained-flow gasifier (BabiTER)
  • Aspen-Simulation of HTC and entrained-flow gasification
  • Carrying out tests on HTC coal gasification in a newly developed technical facility at the IES
  • Ecological and economical evaluation of the technology chain “HTC-Production, gasification, KWK-usage in a BHKW (combined heat and power unit) using the GEMIS program

Projekt Partner: SunCoal Industries GmbH

For more information, contact the employee responsible: Ludwig Briesemeister