Weitere Artikel dieser Ausgabe durch Wischen aufrufen
Responsible editor: Roland Hischier
The decentralization of the Brazilian electricity sector in association with the internal electricity supply crisis has encouraged companies in the sugarcane industry to produce electricity by burning sugarcane bagasse in cogeneration plants. This approach reduces the environmental impact of the sugarcane production and has opened up opportunities for distilleries and annex plants to increase their product portfolios. Potential scenarios for technically and environmentally improving the cogeneration performance were analyzed by using thermodynamic analysis and Life Cycle Assessment (LCA).
The method used in this study aimed to provide an understanding and a model of the electrical and thermal energy production and the environmental impacts of conventional vapor power systems which operate with a Rankine cycle that are commonly used by Brazilian distilleries. Vapor power system experts have suggested focusing on the following technical improvement areas: increasing the properties of the steam from 67 bar and 480 °C to 100 bar and 520 °C, regeneration, and reheating. Eight case scenarios were projected based on different combinations of these conditions. A functional unit of “To the delivery of 1.0 MWh of electricity to the power grid from a cogeneration system” was defined. The product system covers the environmental burdens of the industrial stage and the agricultural production of sugarcane.
Technical evaluation indicated that the energy efficiency improves as the pressure at which the vapor leaves the boiler increases. Simultaneously, the net power exported to the grid increases and the makeup water consumption in the cooling tower and the makeup water supplied to the boiler reduce. From the LCA, it was noted that the improved energy performance of the system is accompanied by reduced environmental impacts for all evaluated categories. In addition, vapor production at 100 bar and 520 °C results in greater environmental gains, both in absolute and relative terms.
Reheating and regeneration concepts were found to be considerably effective in improving the energy and environmental performance of cogeneration systems by burning sugarcane bagasse. For the evaluated categories, the results indicate that the proposed modifications are favorable for increasing the efficiency of the thermodynamic cycle and for decreasing the environmental impacts of the product system.
ANP—National Petroleum, Natural Gas and Biofuels Agency (2011) Brazilian statistical yearbook of oil, natural gas and biofuels. Rio de Janeiro, p 282
ANP—National Petroleum, Natural Gas and Biofuels Agency (2012) Brazilian Statistical Yearbook of oil, natural gas and biofuels. Rio de Janeiro. p 280
Bocci E, Di Carlo A, Marcelo D (2009) Power plant perspectives for sugarcane mills. Energy 34:689–698 CrossRef
Cavalett O, Chagas M, Seabra J, Bonomi A (2013) Comparative LCA of ethanol versus gasoline in Brazil using different LCIA methods. Int J Life Cycle Assess 18:647–658
CGEE (Center for Strategic Studies and Management) (2008) Bioethanol sugarcane: energy for sustainable development. BNDES, Rio de Janeiro
Dias M, Modesto M, Ensinas A, Nebra S, Filho R, Rossel C (2011) Improving bioethanol production from sugarcane: evaluation of distillation, thermal integration and cogeneration systems. Energy 36(6):3691–3703 CrossRef
Gaudreault C, Sanson R, Stuart P (2010) Energy decision making in a pulp and paper mill: selection of LCA system boundary. Int J Life Cycle Assess 15:198–211
Gil M, Moya A, Domíngues E (2013) Life cycle assessment of the cogeneration processes in the Cuban sugar industry. J Clean Prod 41:222–231 CrossRef
Goedkoop M, Heijungs R, Huijbregts M, De Schryver A, Struijs J (2013) Description of the ReCiPe methodology for life cycle impact assessment. In: ReCiPe main report (revised 13 May 2012). http://www.lcia-recipe.net. Accessed 7 Sept 2012
Gonzáles-García S, Iribarren D, Susmozas A, Dufour J, Murphy R (2012) Life cycle assessment of two alternative bioenergy systems involving Salix spp. biomass: bioethanol production and power generation. Appl Energy 95:111–122 CrossRef
Green, M. (1987) Energy in pesticide manufacture, distribution and use. In: Helsel ZR (ed.) Energy in plant nutrition and pest control, Vol. 7. Elsevier, Amsterdam, ISBN 0-444-42753-8, pp. 165–177
ISO 14040 (2006a) International Organization for Standardization, Environmental management—life cycle assessment—principles and framework. Geneva. p 21
ISO 14044 (2006b) International Organization for Standardization, Environmental management—life cycle assessment—requirements and guidelines. Geneva, 52p
Lucas S, Vall MP (1999) Pesticides in the European Union. Agriculture, Environment, Rural Development—Facts and Figures. European Communities. http://europa.eu.int/comm/agriculture/envir/report/en/pest_en/report_en.htm
Luo L, Voet E, Huppes G (2008) Life cycle assessment and life cycle costing of bioethanol from sugarcane in Brazil. Renew Sustain Energy Rev 13:1613–1619 CrossRef
Macedo I, Seabra J, Silva J (2008) Greenhouse gases emissions in the production and use of ethanol from sugarcane in Brazil. The 2005/2006 averages and prediction for 2020. Biomass 7. Energy 32:582–595
MAPA (Ministry of Agriculture, Livestock and Supply) (2011) Secretariat and bioenergy production, sugar and ethanol in Brazil. Harvest 2010–2011. Industry statistics, Brasília
MME (Ministry of Mines and Energy) (2011) Review Brazilian energy 2010. MME, Brasília
Moran J, Shapiro N (2008) Fundamentals of engineering thermodynamics, 6th edn. John Wiley & Sons, New York
Nguyen T, Gheewala S (2008) Life cycle assessment of fuel ethanol from cane molasses in Thailand. Int J Life Cycle Assess 13:301–311
Ometto A, Hauschild M, Roma W (2009) Lifecycle assessment of fuel ethanol from sugarcane in Brazil. Int J Life Cycle Assess 14:236–247
Renouf M, Pagan R, Wegener M (2011) Life cycle assessment of Australian sugarcane products. Int J Life Cycle Assess 16:125–137
Sousa E, Macedo I (Org.) (2010) Ethanol and bioelectricity: sugarcane in the future energy mix. Luc Communication Project, São Paulo
Tina G, Passarello G (2011) Short-term scheduling of industrial cogeneration systems for annual revenue maximization. Energy 42:46–56 CrossRef
- Comparative analysis of electricity cogeneration scenarios in sugarcane production by LCA
João Paulo Macedo Guerra
José Roberto Coleta Jr.
Luiza Carvalho Martins Arruda
Gil Anderi Silva
- Springer Berlin Heidelberg
The International Journal of Life Cycle Assessment
Print ISSN: 0948-3349
Elektronische ISSN: 1614-7502