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| Author(s): |
Guilherme Bezzon
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | Campinas, SP. |
| Institution: | Universidade Estadual de Campinas (UNICAMP). Faculdade de Engenharia Mecânica |
| Defense date: | 1998-04-06 |
| Examining board members: |
Carlos Alberto Luengo;
Luís Augusto Barbosa Cortez;
Sérgio Valdir Bajay;
Jose Carlos de Sousa;
Manuel Regis Lima Verde Leal
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| Advisor: | Carlos Alberto Luengo |
| Abstract | |
An alternative way for reducing environmental problems generated by the largescale use of fossil fuels is the rational and sustainable use of biomass, a renewable energy source, which can contribute for controlling regional and global environment conditions. Charcoal is an important solid fuel derived from biomass, which is usually produced by low efficiency technologies, resulting in native forestry exploitation. The reforestation and the use of more efficient technologies for charcoal making, are alternatives for a better use of the available energy potential in biomass. A gain in charcoal commercial value can be achieved by the modification of its internal structure through a controlled oxidation, which originates activated carbon, a material with special adsorptive properties, used for separation, purification, and pollutants remotion, in liquid and gas phases. Higher yields in the production of charcoal and activated carbon from biomass were achieved, through the development of a new technology based on the controlled pyrolysis at elevated pressures and further activation of the remaining charcoal, using oxygen as activating agent. This technology was evaluated by an experimental analysis and a numerical model of the activation process. Experimental tests were conducted, using the structure and equipments of the "Grupo Combustíveis Alternativos- UNICAMP" and the Hawaii Natural Energy Institute - University of Hawaii. The biomass pyrolysis at elevated pressures resulted in high yields of charcoal with good commercial properties, while the activation process resulted in high yietds of activated carbon with medium adsorptive characteristics. These technologies can open the possibility of new markets, with a rational use of the biomass resources, and fmally, introduce a feasible alternative for fossil fuels, reducing environmental problems (AU) | |