VAPOR-LIQUID EQUILIBRIUM CALCULATION FOR SIMULATION OF BIOETHANOL CONCENTRATION FROM SUGARCANE

Matugi, Karina; Chiavone-Filho, Osvaldo; Ribeiro, Marcelo Perencin de Arruda; Soares, Rafael de Pelegrini; Giordano, Roberto de Campos

doi:10.1590/0104-6632.20180352s20160278

Acessibilidade / Reportar erro

Brasil

Brazilian Journal of Chemical Engineering

Español English

Brasil

Español English

sumário « anterior atual seguinte »

Sumário

CBTermo-2015 • Braz. J. Chem. Eng. 35 (2) • Apr-Jun 2018 • https://doi.org/10.1590/0104-6632.20180352s20160278 copy

VAPOR-LIQUID EQUILIBRIUM CALCULATION FOR SIMULATION OF BIOETHANOL CONCENTRATION FROM SUGARCANE

Authorship SCIMAGO INSTITUTIONS RANKINGS

ABSTRACT

The robustness of the simulation of bioethanol concentration from sugarcane faces two major challenges: the presence of several minor components and the nonlinear behavior of vapor-liquid equilibrium (VLE) calculations. This work assesses the effect of simplifications to overcome these difficulties. From a set of seventeen substances, methanol, n-propanol, isobutanol, 2-methyl-1-butanol and 3-methyl-1-butanol were selected through the examination of the influence of each minor component on vapor-liquid equilibrium calculations of ethanol-water-third component systems. The selection procedure was based on Txy diagrams built using the modified Raoult's law. The influence of the ratio between the vapor phase fugacity coefficients and of the Poynting correction factor were verified. The accuracy of four correlations for vapor pressure was evaluated, and two functional-group activity coefficient models were scrutinized: the recent Functional-Segment Activity Coefficient (F-SAC) and the UNIFAC-Do model.

Keywords:
vapor-liquid equilibrium in ethanol production; vapor pressure; Poynting factor; fugacity coefficient; F-SAC

minor component	mass fraction	mole fraction	stream
methanol	0.0030070	0.0038676	hydrous ethanol
isopropanol	0.0000010	0.0000003	wine
n-propanol	0.0163570	0.0088963	fusel oil
isobutanol	0.0524730	0.0231409	fusel oil
3-methyl-1-butanol	0.2453470	0.0909579	fusel oil
ethyl acetate	0.0008010	0.0003746	hydrous ethanol
acetaldehyde	0.0000180	0.0000168	hydrous ethanol
acetone	0.0000010	0.0000003	wine
acetic acid	0.0002560	0.0000769	vinasse
2-butanol	0.0015960	0.0007040	fusel oil
2-methyl-1-butanol	0.0688440	0.0255226	fusel oil
1-pentanol	0.0000500	0.0000185	fusel oil
1-hexanol	0.0000250	0.0000080	fusel oil
methyl acetate	0.0000010	0.0000003	wine
propionic acid	0.0000640	0.0000156	vinasse
n-butanol	0.0018620	0.0008214	fusel oil
CO₂	0.0011000	0.0004668	wine

Substance	P^vp_i,calc (bar) by the extended Antoine equation		\|ΔP^vp_i\| averages (bar) for each model				Ref.^* * Reference: 1 – Perry and Green (2008); 2 - Čenský et al. (2010). (n. exp. points)
Substance	T= 350 K	T= 390 K	Antoine	extended Antoine	Wagner	CHERIC
water	0.4165	1.793	0.0069	0.001	0.0009	0	1 (5)
methanol	1.6135	5.8339	0.0446	0.0106	0.0046	0.0143	1 (7)
ethanol	0.9564	3.8768	0.0113	0.0059	0.0019	0.0148	1 (15)
n-propanol	0.4441	2.0282	0.0024	0.0037	0.0062	0.0116	1 (20)
isobutanol	0.2832	1.4028	0.0004	0.0059	0.0019	0.0074	1 (18)
2-methyl-1-butanol	0.1149	0.6185	0.0209	0.0171	0.0209	0.0084	2 (14)
3-methyl-1-butanol	0.1069	0.6112	0.0157	0.0086	0.0162	0.0068	2 (9)
		average	0.0145	0.0081	0.0081	0.0094

System component 1 – component 2	γ_i model	Averages of \|ΔP\|_rel %	Averages of \|y₁\|_rel %	n. pts	Ref.^* * For this work: vapor pressure calculated by the extended Antoine equation. Experimental data from Gmehling et al. (1982), except for the ethanol – 2-methyl-1-butanol, from Resa et al. (2005).
ethanol – water	UNIFAC-Do	1,63	2,43	1476	(1)
ethanol – water	F-SAC	1,65	2,28	1476	(1)
ethanol – methanol	UNIFAC-Do	16,15	5,48	110	(1)
	F-SAC	0,82	0,35	110	(1)
	UNIFAC-Do	n.a.	6.1	n.a.	(2)
	NRTL	n.a.	3.5	n.a.	(3)
	UNIFAC	n.a.	6.8	n.a.	(3)
ethanol – n-propanol	UNIFAC-Do	1,60	0,76	80	(1)
	F-SAC	1,46	0,71	80	(1)
	NRTL	n.a.	7.5	n.a.	(3)
	UNIFAC	n.a.	7.6	n.a.	(3)
ethanol – isobutanol	UNIFAC-Do	3,35	0,42	81	(1)
	F-SAC	3,53	0,45	81	(1)
	NRTL	n.a.	1.4	n.a.	(3)
	UNIFAC	n.a.	1.8	n.a.	(3)
ethanol – 2-methyl-1-butanol	UNIFAC-Do	0,94	7,80	22	(1)
ethanol – 2-methyl-1-butanol	F-SAC	1,49	8,75	22	(1)
ethanol – 3-methyl-1-butanol	UNIFAC-Do	3,64	0,59	61	(1)
	F-SAC	3,10	0,48	61	(1)
	NRTL	n.a.	2.3		(3)
	UNIFAC	n.a.	2.2		(3)
water – methanol	UNIFAC-Do	2,21	1,12	898	(1)
	F-SAC	2,42	1,13	898	(1)
	NRTL	n.a.	2.4		(3)
	UNIFAC	n.a.	3.7		(3)
water – n-propanol	UNIFAC-Do	1,97	1,42	602	(1)
	F-SAC	1,79	1,35	602	(1)
	NRTL	n.a.	5.9		(3)
	UNIFAC	n.a.	8.6		(3)
water – isobutanol	UNIFAC-Do	18,20	12,94	97	(1)
	F-SAC	11,53	9,63	97	(1)
	NRTL	n.a.	6		(3)
	UNIFAC	n.a.	5.8		(3)
water – 3-methyl-1-butanol	UNIFAC-Do	8,12	4,00	63	(1)
	F-SAC	9,04	4,10	63	(1)
	NRTL	n.a.	2.8		(3)
	UNIFAC	n.a.	35.4		(3)

Brazilian Society of Chemical Engineering Rua Líbero Badaró, 152 , 11. and., 01008-903 São Paulo SP Brazil, Tel.: +55 11 3107-8747, Fax.: +55 11 3104-4649, Fax: +55 11 3104-4649 - São Paulo - SP - Brazil
E-mail: rgiudici@usp.br

Acompanhe os números deste periódico no seu leitor de RSS

[1] * Corresponding author: roberto@ufscar.br