Harvesting technologies and value-adding to biofuels of herbaceous biomasses

The exigency for developing alternative energy sources is one of the most important priorities for countries whose energetic consumption is strongly dependent on fossil combustibles: such need can be reduced to economical-strategic reasons, mainly because of the geographical distribution of energy sources of fossil origin in politically unstable regions. Another important aspect is the environmental one: the ratification of the Kyoto Protocol enforces adherent countries to develop an energetic model founded on renewable technologies. In this background, energy from biomasses emerges like one of the most promising solutions, either for energy production from sources alternative to fossil fuels, or for the contribution to the reduction of greenhouse gases emission in the atmosphere. In particular, energetic cultivations constitute a very interesting resource; such cultivations put us in the position to attain targets like the introduction of an integrated vision of the agricultural development capable of diversifying its activities, the valorization of rural assets and the creation of new sources of employment and profit. For these reasons, in Estonia there is a great interest in energetic use of herbaceous wetland plants. The produced biomass can be used like CO2-neutral energy source, as the amount of greenhouse gasses emitted during combustion is equivalent to the one removed from the atmosphere by plants during their growth thanks to photosynthesis. Moreover, these plants guarantee other environmental benefits, like the vegetal filtration for the treatment of waste water (phytoreclaim) and the contrasting action to erosive phenomena. For the best use of biomass resources, we need to know how much is available, what the limitations are and how to make efficient devices which will harness the energy in a practical, cost-effective way. This work is been developed through the following phases:
1. Introduction to sustainable development and renewable resources, with an extensive treatment of energy from biomass. Issues are treated from a global, European and, finally, Estonian point of view.
2. Presentation of the more abundant and, from an energetic point of view, interesting herbaceous plants in Estonia (since a fundamental characteristic of biomasses is their tight bond with the territory, the biomass energetic potentialities esteem must start from the quantification of biomass amount available in a given territorial context).
3. Analysis of technologies and machines suitable for harvesting Estonian spontaneous herbaceous biomass: the development and optimization of harvesting systems is of fundamental importance for the containment of production costs and the improvement of the energy balance for these type of energy source.
4. Description of the current conversion technologies, able to transform harvested biomass into biofuels suitable for commercialization. Mechanical, thermochemical and biochemical processes are presented.
5. Appraisal of the production cost of the various biofuels from wetland herbaceous biomass. Emphasis is put on the analysis and costs quantification of the harvesting process.