Projects in Brazil

Hydrothermal carbonization using the deep-shaft process

Hydrothermal carbonization (HTC) is a process for the thermochemical conversion of biomass into a brown-coal like solid. In contrast to other processes such as pyrolysis, the HTC process takes place in an aqueous medium. There is hence no need for energy-intensive drying of the raw materials. The HTC process also operates at considerably lower temperatures of just 200°C, compared with ca. 500°C for pyrolysis.

Oil seeds and fruits are major products of the Brazilian agricultural sector. The harvesting and processing of these products result in large amounts of residual materials such as fruit skins, press-cakes, and greenery. Most of these residual materials contain a considerable amount of water, and hence have poor stability to transport and storage. For this reason, these materials have up until now only been economically recycled to a limited degree. They are however highly suitable as raw materials for the HTC process.

As part of a bilateral research project it is planned to further investigate and optimize the use of HTC for recycling residual materials from the Brazilian agricultural and food industries. The carrying out of the process in deep shafts will allow standardization of the reaction conditions due to the hydrostatic water column and will offset regional and seasonal fluctuations in the composition of the raw materials. This will enable products of uniform composition to be manufactured.