Bioethanol Aspen Simulation
i n f o
a b s t r a c t
Ethanol production from lignocellulosic materials is often conceived considering independent, standalone production plants; in the Brazilian scenario, where part of the potential feedstock (sugarcane bagasse) for second generation ethanol production is already available at conventional first generation production plants, an integrated first and second generation production process seems to be the most obvious option. In this study stand-alone second generation ethanol production from surplus sugarcane bagasse and trash is compared with conventional first generation ethanol production from sugarcane and with integrated first and second generation; simulations were developed to represent the different technological scenarios, which provided data for economic and environmental analysis. Results show that the integrated first and second generation ethanol production process from sugarcane leads to better economic results when compared with the stand-alone plant, especially when advanced hydrolysis technologies and pentoses fermentation are included.
1. Introduction Increasing concerns about climate change and energy security have motivated the search for alternative forms of energy (Karuppiah et al., 2008). Since the transportation sector is responsible for a significant fraction of the greenhouse gases emissions, substitution of oil derived fuels by biofuels, like ethanol, could significantly decrease environmental impacts, besides providing gains on the socio-economic levels as well. Brazil and the US are the world’s largest bioethanol producers, using sugarcane and corn as feedstock, respectively. In the Brazilian sugarcane industry, large amounts of lignocellulosic materials (sugarcane bagasse and trash) are produced during sugar and ethanol production. Sugarcane bagasse is currently used as fuel, supplying the energy required for the plant, while sugarcane trash, previously burnt to improve the harvest procedure, is today mostly left in
a b s t r a c t
Ethanol production from lignocellulosic materials is often conceived considering independent, standalone production plants; in the Brazilian scenario, where part of the potential feedstock (sugarcane bagasse) for second generation ethanol production is already available at conventional first generation production plants, an integrated first and second generation production process seems to be the most obvious option. In this study stand-alone second generation ethanol production from surplus sugarcane bagasse and trash is compared with conventional first generation ethanol production from sugarcane and with integrated first and second generation; simulations were developed to represent the different technological scenarios, which provided data for economic and environmental analysis. Results show that the integrated first and second generation ethanol production process from sugarcane leads to better economic results when compared with the stand-alone plant, especially when advanced hydrolysis technologies and pentoses fermentation are included.
1. Introduction Increasing concerns about climate change and energy security have motivated the search for alternative forms of energy (Karuppiah et al., 2008). Since the transportation sector is responsible for a significant fraction of the greenhouse gases emissions, substitution of oil derived fuels by biofuels, like ethanol, could significantly decrease environmental impacts, besides providing gains on the socio-economic levels as well. Brazil and the US are the world’s largest bioethanol producers, using sugarcane and corn as feedstock, respectively. In the Brazilian sugarcane industry, large amounts of lignocellulosic materials (sugarcane bagasse and trash) are produced during sugar and ethanol production. Sugarcane bagasse is currently used as fuel, supplying the energy required for the plant, while sugarcane trash, previously burnt to improve the harvest procedure, is today mostly left in
References: Alonso Pippo, W., Luengo, C.A., Alonsoamador Morales Alberteris, L., Garzone, P., Cornacchia, G., 2011. Energy recovery from sugarcane-trash in the light of 2nd generation biofuels. Part 1: Current situation and environmental aspects. Waste Biomass Valor 2, 1–16. Alvarado-Morales, M., Terra, J., Gernaey, K.V., Woodley, J.M., Gani, R., 2009. Biorefining: computer aided tools for sustainable design and analysis of bioethanol production. Chem. Eng. Res. Des. 87, 1171–1183. Alvira, P., Tomás-Pejó, E., Ballesteros, M., Negro, M.J., 2010. Pretreatment technologies for an efficient bioethanol production process based on enzymatic hydrolysis: a review. Bioresour. Technol. 101, 4851–4861. CEPEA – Center for Advanced Studies on Applied Economics, 2011. (retrieved 15.03.2011). CGEE, 2009. Bioethanol as a Fuel: An Opportunity for Brazil. Brasília (in Portuguese). (retrieved CGEE, Brasília. 30.01.2010). ˇ ˇ Cucek, L., Martín, M., Grossmann, I.E., Kravanja, Z., 2011. Energy, water and process technologies integration for the simultaneous production of ethanol and food from the entire corn plant. Comput. Chem. Eng. 35, 1547–1557. Dias, M.O.S., Ensinas, A.V., Nebra, S.A., Maciel Filho, R., Rossell, C.E.V., Maciel, M.R.W., 2009. Production of bioethanol and other bio-based materials from sugarcane bagasse: integration to conventional bioethanol production process. Chem. Eng. Res. Des. 87, 1206–1216. 4. Conclusions Evaluation of scenarios considering different levels of integration between first and second generation ethanol production plants from sugarcane showed that the integrated first and second generation process using advanced hydrolysis technologies and pentoses fermentation presents several advantages over the stand-alone second generation ethanol production plants, besides the largest M.O.S. Dias et al. / Bioresource Technology 103 (2012) 152–161 Dias, M.O.S., Cunha, M.P., Maciel Filho, R., Bonomi, A., Jesus, C.D.F., Rossell, C.E.V., 2011a. Simulation of integrated first and second generation bioethanol production from sugarcane: comparison between different biomass pretreatment methods. J. Ind. Microbiol. Biotechnol. 38, 955–966. Dias, M.O.S., Modesto, M., Ensinas, A.V., Nebra, S.A., Maciel Filho, R., Rossell, C.E.V., 2011b. Improving bioethanol production from sugarcane: evaluation of distillation, thermal integration and cogeneration systems. Energy 36, 3691– 3703. Dias, M.O.S., Cunha, M.P., Jesus, C.D.F., Rocha, G.J.M., Pradella, J.G.C., Rossell, C.E.V., Maciel Filho, R., Bonomi, A., 2011c. Second generation ethanol in Brazil: can it compete with electricity production? Bioresour. Technol. 102, 8964–8971. Ensinas, A.V., Nebra, S.A., Lozano, M.A., Serra, L.M., 2007. Analysis of process steam demand reduction and electricity generation in sugar and ethanol production from sugarcane. Energy Convers. Manage. 48, 2978–2987. Gírio, F.M., Fonseca, C., Carvalheiro, F., Duarte, L.C., Marques, S., Bogel-Łukasik, R., 2010. Hemicelluloses for fuel ethanol: a review. Bioresour. Technol. 101, 4775– 4800. Guineé, J.B., Gorree, M., Heijungs, R., Huppes, G., Kleijn, R., Sleeswijk, A.W., Haes, H.A.U.D., Bruijn, J.A.D., Duin, R.V., Huijbregts, M.A.J., 2002. Handbook on Life Cycle Assessment: Operational Guide to the ISO Standards. Kluwer Academic Publishers, Dordrecht. Huang, H.-J., Ramaswamy, S., Al-Dajani, W., Tschirner, U., Cairncross, R.A., 2009. Effect of biomass species and plant size on cellulosic ethanol: a comparative process and economic analysis. Biomass Bioenerg. 33, 234–246. ISO, 1998. ISO Norm 14041:1998. Environmental Management – Life Cycle Assessment – Goal and Scope Definition and Inventory Analysis. International Organisation for Standardisation, Geneva. ISO, 2006a. ISO Norm 14040:2006. Life Cycle Assessment: Principles and Framework. Environmental Management. International Organisation for Standardisation, Geneva. ISO, 2006b. ISO Norm 14044:2006. Life Cycle Assessment. Requirements and Guidelines. Environmental Management. International Organisation for Standardisation, Geneva. Karuppiah, R., Peschel, A., Grossmann, I.E., Martín, M., Martinson, W., Zullo, L., 2008. Energy optimization for the design of corn-based ethanol plants. AIChE J. 54 (6), 1499–1525. Kazi, F.K., Fortman, J.A., Anex, R.P., Hsu, D.D., Aden, A., Dutta, A., Kothandaraman, G., 2010. Techno-economic comparison of process technologies for biochemical ethanol production from corn stover. Fuel 89, S20–S28. 161 Leibbrandt, N.H., Knoetze, J.H., Görgens, J.F., 2011. Comparing biological and thermochemical processing of sugarcane bagasse: an energy balance perspective. Biomass Bioenerg. 35, 2117–2126. Macedo, I.C., Seabra, J.E.A., Silva, J.E.A.R., 2008. Green house gases emissions in the production and use of ethanol from sugarcane in Brazil: the 2005/2006 averages and a prediction for 2020. Biomass Bioenerg. 32, 582–595. Martín, M., Grossmann, I.E., in press. Energy optimization of bioethanol production via hydrolysis of switchgrass. AIChE J. doi:10.1002/aic.12735. Melamu, R., von Blottnitz, H., 2011. 2nd generation biofuels a sure bet? A life cycle assessment of how things could go wrong. J. Clean. Prod. 19, 138–144. Nigam, P.S., Singh, A., 2011. Production of liquid biofuels from renewable resources. Prog. Energy Combust. Sci. 37, 52–68. Ojeda, K., Ávila, O., Suárez, J., Kafarov, V., 2011. Evaluation of technological alternatives for process integration of sugarcane bagasse for sustainable biofuels production – Part 1. Chem. Eng. Res. Des. 89, 270–279. Rocha, G.J.M., Gonçalves, A.R., Oliveira, B.R., Olivares, E.G., Rossell, C.E.V., 2012. Steam explosion pretreatment reproduction and alkaline delignification reactions performed on a pilot scale with sugarcane bagasse for bioethanol production. Ind. Crops Prod. 35, 274–279. Seabra, J.E.A., Tao, L., Chum, H.L., Macedo, I.C., 2010. A techno-economic evaluation of the effects of centralized cellulosic ethanol and co-products refinery options with sugarcane mill clustering. Biomass Bioenerg. 34, 1065–1078. Seabra, J.E.A., Macedo, I.C., 2011. Comparative analysis for power generation and ethanol production from sugarcane residual biomass in Brazil. Energy Policy 39, 421–428. Simo, M., Brown, C.J., Hlavacek, V., 2008. Simulation of pressure swing adsorption in fuel ethanol production process. Comput. Chem. Eng. 32, 1635–1649. Stanmore, B.R., 2010. Generation of energy from sugarcane bagasse by thermal treatment. Waste Biomass Valor 1, 77–89. Tao, L., Aden, A., 2009. The economics of current and future biofuels. In Vitro Cell. Dev. Biol.: Plant 45, 199–217. UDOP – Union of Biofuel Producers, 2011. Sugarcane Prices. (retrieved 15.03.2011). Wooley, R.J., Putsche, V., 1996. Development of an ASPEN PLUS Physical Property Database for Biofuels Components. Report No. NREL/MP-425-20685, NREL, Golden, Colorado. (retrieved 01.03.2007). Yin, D., Jing, Q., AlDajani, W.W., Duncan, S., Tschirner, U., Schilling, J., Kazlauskas, R.J., 2011. Improved pretreatment of lignocellulosic biomass using enzymaticallygenerated peracetic acid. Bioresour. Technol. 102, 5183–5192.