Thermal gasification is a process that converts carbonaceous materials (e.g. biomass and bio-waste) into gases rich in CO and H2 at temperatures >700 °C. The product gas from thermal gasification is called producer gas (or wood gas when the process is fueled by wood) and may be converted to high quality energy carriers such as electricity or liquid fuels. Also, corrosive ash elements such as chloride and potassium may be retained by the gasification process, allowing the gas from otherwise problematic fuels to be used in efficient power plant boilers.
Pyrolysis is a thermal process where biomass is heated up to 400-600°C whereby gas, char and a bio oil are produced. The Bio oil produced by pyrolysis can be utilized as liquid fuel for boilers or as fuel for heavy duty diesel engines. The produced char may be used as a bio-char to improve soil quality.
Research goal and purpose
Thermal gasification provides highly efficient production of combined heat and power (CHP) and offers the possibility for utilization of a wide range of biomass residues ranging from wood to sewage sludge and animal manure. Different gasification technologies will be applicable in scales from mini-CHP to centralized power plant.
It is the aim of the activities to be leading in research, development and innovation concerning thermal gasification technologies for highly efficient combined heat and power production and/or production of clean fuel e.g. methanol or bio-SNG (Synthetic Natural Gas). The established knowledge is used to solve general as well as specific problems related to gasification and pyrolysis and valuable experience is gathered based on work with laboratory, pilot and development projects.
The work within this area focuses on:
- Low temperature gasification of low-grade biomass for co-firing in large scale power plants
- Up-grading of product gas from low temperature gasification. Removing particles and converting the tars in the product gas will widen the application range of this technology significantly
- Efficiency and availability optimization of small scale biomass gasification systems for CHP
- BioSOFC (Solid Oxide Fuel Cells), 3rd generation biomass gasification CHP
- Utilization of nutrients and residual char in the ashes from biomass gasification plants
- Optimization of ash quality with regard to carbon content, plant availability and toxicity
- Further development and demonstration of the DTU TwoStage biomass gasification technology and the PYRONEER (Low Temperature Circulating Fluid Bed) gasification technology for CHP and fuel production
- Efficiency optimization of CHP gas engine operation on biomass producer gas
- Technology transfer to developing countries
- Optimization of entrained flow gasification to minimize soot formation
- Use of gasification gas for synthesis of liquid fuels and chemicals
- Optimization of the pyrolysis process to make use of a broad range of different fuels
- Hydrodeoxygination of pyrolysis oils to improve pyrolysis oil quality.