Tag Archives: bio-methane

22-40 F. da Borso, C. Di Marzo, F. Zuliani, F. Danuso and M. Baldini
Harvest time and ensilage suitability of giant reed and miscanthus for bio-methane production and characterization of digestate for agronomic use
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Harvest time and ensilage suitability of giant reed and miscanthus for bio-methane production and characterization of digestate for agronomic use

F. da Borso, C. Di Marzo, F. Zuliani, F. Danuso and M. Baldini*

Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Via delle Scienze, 206, IT33100 Udine, Italy
*Correspondence: mario.baldini@uniud.it

Abstract:

In many countries, biogas plants are mainly fed by livestock slurry and dedicated crops, including maize, which still represents one of the main energy crops utilized. Many concerns are now arising on environmental impact due to the high water consumption, chemical fertilizer and pesticide requirements and on adverse effect of maize as energy crop on the price of food and feed commodities. For these reasons two perennial crops, in particular miscanthus (Miscanthus x giganteus) and giant reed (Arundo donax L.), were cultivated at very low input and evaluated for their bio-methane yield at different harvest times and ensilage suitability, in a north-eastern area of Italy. Moreover, considering the agronomic use of the obtained digestate as fertilizer, this has been characterized by the content of heavy metals. Both multi-annual crops have proved highly productive in biomass especially with a harvest time in autumn, at which a satisfactory completion of the silage process without additives was observed. Conversely, bio-methane yield per hectare were not satisfactory with respect to the reference crops such as maize. The low BMP attained showed the main bottleneck of the methanisation of ensiled giant-reed and miscanthus, which is represented by fiber composition with high degree of lignification. The simulation use of digestate obtained as fertilizer in vulnerable areas, could lead to slightly exceed the levels allowed by the legislation of some European countries with regard of heavy metals as Cu, Zn and Cd.

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999-1006 M. Repele, A.Paturska, K. Valters and G. Bazbauers
Life cycle assessment of bio-methane supply system based on natural gas infrastructure
Abstract |
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Life cycle assessment of bio-methane supply system based on natural gas infrastructure

M. Repele*, A.Paturska, K. Valters and G. Bazbauers

Institute of Energy Systems and Environment, Riga Technical University, Kronvalda Boulevard 1, Riga, LV1010, Latvia; *Correspondence: mara.repele@rtu.lv

Abstract:

Many sites for biogas production in Latvia currently do not have sufficient heat load to provide power production in co-generation mode. The alternative to relatively inefficient power production could be production of bio-methane which is known as one of the most important renewable option for gas supplies. After removal of contaminants bio-methane is of quality of natural gas and can be delivered to power plants and industry using the natural gas supply infrastructure. For analysis of environmental benefit of using bio-methane the environmental impact of the proposed solution has to be assessed. The aim of the study is to make life cycle assessment of the system for bio-methane supply to industrial plant via the natural gas grid. The analysed system includes bio-methane production and transport to the natural gas pipeline including the infrastructure. Functional unit was 1 MWh of bio-methane energy injected into the natural gas transmission pipeline. Life-cycle model was created and analysed with software ‘SimaPro’. ReCiPe and Eco-Indicator’99 were used as characterization methods to analyse the life-cycle environmental impacts. Results show the influence and contribution level expressed in mid-point categories as well as in a single-score indicator. The largest impact is created by use of fossil energy sources in production of bio-methane. The results can be used to design renewable energy supply systems and for the comparison of alternatives.

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