Hydrothermal conversion of biomass at supercritical conditions for gaseous fuel production: results, new challenges, and developments

A4 Conference proceedings


Internal Authors/Editors


Publication Details

List of Authors: C. De Blasio, T. Kohl, M. Magdeldin, T. Westerlund, M. Järvinen
Publication year: 2015
Book title: The International Chemical Congress of Pacific Basin Societies, December 15-20, 2015, Honolulu, Hawaii


Abstract

Biomass conversion in supercritical water represents one of the emerging areas of the reaction engineering. Additionally, Supercritical Water Gasification, SCWG, offers great possibilities for new ways of reactors design and operations. Reactive separation processes represent the future in this sense. In our studies experiments were done on SCWG of diverse biomass samples in tubular reactors of same dimensions. Reactors were made of stainless steel and nickel-chromium-molybdenum, INCONEL 625; the second was used to test the catalytic effect of nickel alloy. Different physical conditions were considered and tests were performed at temperatures between 500°C and 800°C. In addition to simple organic liquid solutions, complex kinds of feedstock like black liquor were tested in order to retrieve information on the effects of homogeneous catalysis and precipitation of salts. Salts and inorganic chemicals precipitation from black liquor in supercritical water have high interest among pulp and paper companies. Our research has confirmed the active participation of water during the biomass gasification process and new information on the reaction mechanism between ethylene and ethane at supercritical water conditions was obtained. Degradation of sugars was found to proceed rapidly with respect to the formation of acids which were found to be more difficult to decompose. Furthermore, it was established that INCONEL 625 alloy, acting as a catalyst, increases the efficiency of gasification expressed in terms of carbon conversion to methane and ethane. The cold gas efficiency improved significantly when the nickel alloy was used. Novel results and information were obtained on polycyclic aromatic compounds degradation at temperatures between 500°C and 800°C. Very accurate tests for constant and extremely low mass flows with online measurements are to be carried out during spring 2015 along with experiments on non-miscible solutions.

Last updated on 2019-21-07 at 05:03