Exergetic, environmental and economic assessment of sugarcane first–generation biorefineries

  • Pablo Silva Ortiz University of Campinas – UNICAMP
  • Daniel Flórez-Orrego University of São Paulo - USP
  • Silvio de Oliveira Junior University of São Paulo - USP
  • François Maréchal École Polytechnique Fédérale de Lausanne - EPFL
  • Rubens Maciel Filho University of Campinas – UNICAMP


First generation ethanol (1G) contributes to the majority of the ethanol produced worldwide, predominantly centered on cornand sugarcane. Nevertheless, several issues are regularly highlighted concerning the long-term sustainability of this technology,including its intensive water and land use, potential contamination of soils through the distillation residues, as well as thebalance between fuel and food crops. Accordingly, in this study, a process design approach for biomass to ethanol production(1G ethanol technology) from sugarcane was performed by using Aspen Plusr software, based on the autonomous distillery(AUT, ethanol production) and the annexed plant (ANX, joint ethanol and sugar production) configurations. In addition, a performancecomparison in respect to the exergy efficiency and the irreversibility as quality indicators of the conversion processesis carried out to identify potential improvements in the production facilities. Hence, the shortcomings of the techno-economicassessment of ethanol production can be overcome by using exergy efficiency as a suitable indicator for process performance.Moreover, the technical/sustainability aspects related to the process design of the sugarcane biorefineries are discussed inlight of the renewability exergy index (). In general, the ANX plant has a saving in the process irreversibility rate of about 6%, whereas the average unitary exergy cost is 10% lower (AUEC= 2.41 kJ/kJ), in contrast to the AUT distillery. Moreover, atechno-economic analysis was carried out to assess the annexed plant and the autonomous distillery systems, consideringthe estimated capital expenditure. The results indicated that the ANX biorefinery has higher capex than the AUT distillery. Itis noted that the higher investments are associated with sugarcane reception, ethanol production (juice extraction) and thecombined heat and power sub-systems. Concerning system performance, the ANX plant presented a better overall exergyefficiency, with 41.39 %. Although this multi-criteria analysis is applied to 1G ethanol technology; it may be well-matchedfor various biorefineries/bioprocesses as a methodology to support decision-making as concerns potential improvement, wellahead of detailed process design.


[1] K. J. Ptasinski, Efficiency of biomass energy: an exergy approach to
biofuels, power, and biorefineries, John Wiley & Sons, 2016.
[2] Rfa, renewable fuels association - leading trade association for us
ethanol, renewable fuels association. (n.d.). https://ethanolrfa.org/ (accessed
october 9, 2018).
[3] Epe, brazilian energy balance 2017, epe. (n.d.).
brazilian-energy-balance-2017 (accessed january 13, 2019).
[4] A. Ensinas, M. Modesto, S. Nebra, L. Serra, Reduction of irreversibility
generation in sugar and ethanol production from sugarcane, Energy
34 (5) (2009) 680–688.
[5] L. F. Pellegrini, S. de Oliveira Junior, Combined production of sugar,
ethanol and electricity: thermoeconomic and environmental analysis
and optimization, Energy 36 (6) (2011) 3704–3715.
[6] E. A. Pina, R. Palacios-Bereche, M. F. Chavez-Rodrigues, A. V. Ensinas,
M. Modesto, S. A. Nebra, et al., Thermal integration of different
plant configurations of sugar and ethanol production from sugarcane,
[7] J. Q. Albarelli, A. V. Ensinas, M. A. Silva, Product diversification to
enhance economic viability of second generation ethanol production
in brazil: the case of the sugar and ethanol joint production, Chemical
Engineering Research and Design 92 (8) (2014) 1470–1481.
[8] D. Flórez-Orrego, J. A. da Silva, H. Velásquez, S. de Oliveira Jr, Renewable
and non-renewable exergy costs and co2 emissions in the
production of fuels for brazilian transportation sector, Energy 88 (2015)
[9] M. O. Dias, M. Modesto, A. V. Ensinas, S. A. Nebra, R. Maciel Filho,
C. E. Rossell, Improving bioethanol production from sugarcane: evaluation
of distillation, thermal integration and cogeneration systems, Energy
36 (6) (2011) 3691–3703.
[10] L. pellegrini, m. modesto, s.a. nebra, s. oliveira junior, modern concept
for ethanol distilleries: Maximization of the electricity surplus, proceedings
of encit-abcm, belo horizonte-mg, brazil. (2008).
[11] M. Modesto, A. Aoki, A. Lodi, E. Pina, Assessment of the potential to
increase electricity generation from sugarcane straw in brazilian sugarcane
cogeneration plants, Chemical Engineering Transactions 50
(2016) 193–198.
[12] R. Palacios-Bereche, K. J. Mosqueira-Salazar, M. Modesto, A. V. Ensinas,
S. A. Nebra, L. M. Serra, M.-A. Lozano, Exergetic analysis of the
integrated first-and second-generation ethanol production from sugarcane,
Energy 62 (2013) 46–61.
[13] E. A. Pina, R. Palacios-Bereche, M. F. Chavez-Rodriguez, A. V. Ensinas,
M. Modesto, S. A. Nebra, Reduction of process steam demand
and water-usage through heat integration in sugar and ethanol production
from sugarcane–evaluation of different plant configurations, Energy
138 (2017) 1263–1280.
[14] A. V. Ensinas, V. Codina, F. Marechalb, J. Albarelli, M. A. Silva,
Thermo-economic optimization of integrated first and second generation
sugarcane ethanol plant, Chemical Engineering 35.
[15] M. Dias, O. Cavalett, R. Maciel Filho, A. Bonomi, Integrated first and
second generation ethanol production from sugarcane, Chemical Engineering
Transactions 37 (2014) 445–450.
[16] A. Bonomi, T. Junqueira, M. Chagas, V. Gouveiaa, M. Watanabe,
O. Cavalett, Techno-economic and environmental assessment of second
generation ethanol: Short and long term prospects, Chemical Engineering
Transactions 50 (2016) 439–444.
[17] P. Silva-Ortiz, R. Maciel Filho, Comparative performance indexes for
ethanol production based on autonomous and annexed sugarcane
plants, Chemical Engineering Transactions 65 (2018) 625–630.
[18] R. Palacios-Bereche, A. V. Ensinas, M. Modesto, S. A. Nebra, et al.,
Extraction process in the ethanol production from sugarcane–a comparison
of milling and diffusion, CHEMICAL ENGINEERING 39.
[19] M. O. Dias, T. L. Junqueira, I. L. Sampaio, M. F. Chagas, M. D. Watanabe,
E. R. Morais, V. L. Gouveia, B. C. Klein, M. C. Rezende, T. F.
Cardoso, et al., Use of the vsb to assess biorefinery strategies, in:
Virtual Biorefinery, Springer, 2016, pp. 189–256.
[20] M. O. d. S. Dias, et al., Desenvolvimento e otimização de processos
de produção de etanol de primeira e segunda geração e eletricidade
a partir da cana-de-açúcar, development and optimization of
first and second generation bioethanol and electricity production processes
from sugarcane.
[21] M. O. d. S. Dias, et al., Simulação do processo de produção de etanol
a partir do açúcar e do bagaço, visando a integração do processo
e a maximização da produção de energia e excedentes do bagaço,
simulation of ethanol production processes from sugar and sugarcane
bagasse, aiming process integration and maximization of energy and
bagasse surplus.
[22] A. Bonomi, O. Cavalett, M. CUNHA, M. A. Lima, Virtual biorefinery,
Cham: Springer International Publishing.
[23] Aspen plus, (n.d.). https://www.aspentech.com/en/products/engineering/aspenplus
(accessed october 9, 2018).
[24] J. Szargut, D. Morris, F. Steward, Exergy analysis of thermal, chemical
and metallurgical processes, hemisphere publ, Corp., New York (1988)
[25] T. Kotas, The exergy method of thermal plant analysis.
[26] P. S. Ortiz, S. de Oliveira Jr, Exergy analysis of pretreatment processes
of bioethanol production based on sugarcane bagasse, Energy
76 (2014) 130–138.
[27] P. S. Ortiz, S. de Oliveira Jr, Compared exergy analysis of sugarcane
bagasse sequential hydrolysis and fermentation and simultaneous
saccharification and fermentation, International Journal of Exergy
19 (4) (2016) 459–480.
[28] S. de Oliveira Junior, Exergy: production, cost and renewability,
Springer Science & Business Media, 2012.
[29] M. Lozano, A. Valero, Theory of the exergetic cost, Energy 18 (9)
(1993) 939–960.
[30] R. Turton, R. C. Bailie, W. B. Whiting, J. A. Shaeiwitz, Analysis, synthesis
and design of chemical processes, 5th edition, Pearson Education,
[31] G. D. Ulrich, G. D. Ulrich, P. T. Vasudevan, A Guide to Chemical Engineering
Process Design and Economics: A Practical Guide, CRC,
[32] W. D. Seider, D. R. Lewin, J. Seader, S. Widagdo, R. Gani, K. M. Ng,
Product and process design principles: Synthesis, analysis and evaluation,
4th edition.
[33] D. Stolten, V. Scherer, Transition to renewable energy systems, John
Wiley & Sons, 2013.
How to Cite
SILVA ORTIZ, Pablo et al. Exergetic, environmental and economic assessment of sugarcane first–generation biorefineries. Journal of Power Technologies, [S.l.], v. 99, n. 2, p. 67–81, apr. 2019. ISSN 2083-4195. Available at: <https://papers.itc.pw.edu.pl/index.php/JPT/article/view/1517>. Date accessed: 23 july 2021.
Contemporary Problems of Thermal Engineering 2018 Gliwice


Exergy analysis, Thermo-economic, Sugarcane bagasse, Irreversibilities, Cogeneration Systems and Environmental performance.

Most read articles by the same author(s)

Obs.: This plugin requires at least one statistics/report plugin to be enabled. If your statistics plugins provide more than one metric then please also select a main metric on the admin's site settings page and/or on the journal manager's settings pages.