Search

• The distillation sequences for ABE purification from the GSVP condensate was investigated. • Techno-economic analysis was conducted to evaluate the ABE distillation sequences. • The sequence contained 3 columns, one decanter and two loops exhibited the best ABE purification performances. Gas stripping-vapor permeation (GSVP) is an attractive method for in situ acetone-butanol-ethanol (ABE) separation from fermentation broth to obtain renewable biological n-butanol. However, the downstream distillation systems for effective purification of ABE from the upstream GSVP process has not been developed. In this study, focusing on the generation of high purify A-B-E solvents as the final products, the downstream distillation systems for GSVP condensate purification were investigated. According to literature survey, four candidate distillation sequences were selected and optimized by steady-state simulation, followed by cross-over comparisons of energy requirements, techno-economics and environmental influences. The results indicate that the Scenario 3 that containing three individual columns and one decanter exhibited the lowest sensitivity to the key factors, lowest total annual cost (6.483 × 106 $/yr) and CO 2 emission (3707.23 kg/h) in a scheme with 30 kt/yr n-butanol production among the four candidate distillation sequences. This study provides a valuable reference for the development of downstream ABE separation and purification processes in future works. [Display omitted] [ABSTRACT FROM AUTHOR]

Highlights • Biphasic acetone-butanol-ethanol after in situ gas stripping was purified by distillation. • Four distillation sequences were investigated and optimized. • Techno-economic analysis was carried out to choose favorable sequences. • Energy requirement of distillation was decreased by 25.8%. • Total annual cost of distillation was decreased by 17.4%. Abstract Distillation processes for separation of biphasic ABE solution from in situ gas stripping were developed. The distillation sequences were investigated and optimized. Results proved the energy requirement of distillation was effectively reduced when feeding the biphasic ABE mixture. After techno-economic analysis, a superior scenario that started with a decanter followed with side-by-side sequences for separation acetone and ethanol was selected. Compared with the conventional processes that detractively concentrate the biphasic ABE mixture, energy requirement and total annual cost (TAC) of the novel distillation process were decreased by 25.8% and 17.4%, respectively. $ 4102.98 K per year of TAC was estimated in a case with a capacity of 30 K tons of butanol per year. [ABSTRACT FROM AUTHOR]

In this study, an integrated gas stripping–pervaporation (GS–PV) process was established to enhance the butanol concentration and to reduce the cost of the product separation processes. Batch pervaporation was integrated with in situ gas stripping system of fed-batch acetone–butanol–ethanol (ABE) fermentation. A total 706.68 g/L ABE (54.2 g/L of ethanol, 169.93 g/L of acetone, and 482.55 g/L of butanol) was collected after 11 h of pervaporation separation. The recovery rates of butanol, acetone and ethanol were 98.8%, 99.5% and 82.8% (w/v), respectively. Attractively, the liquor on the permeate side of pervaporation membrane exceeded its azeotropic point which have not been achieved in previous processes basing on individual gas stripping or pervaporation. Furthermore, aiming to construct consolidate commercial guide of biobutanol producing process, GS–PV–distillation process was established and compared with traditional GS–distillation scheme. As a result, 24.83 MJ/kg of butanol was consumed in the novel GS–PV–distillation process. In this scheme, the beer column was deleted from the rectifying column series. Moreover, based on the consolidate GS–PV–distillation integration process, heat recovery network was simulated and designed by Pinch Analysis, and 1.72 MJ/kg of heat could be further saved after heat exchange in the distillation system. And the overall energy demand for butanol production was further decreased to 23.07 MJ/kg, which was only 29.2% of the conventional distillation procedure. [ABSTRACT FROM AUTHOR]

Integrating the acetone-butanol-ethanol fermentation with pervaporation or gas stripping for in situ product recovery is considered as an effective way for biobutanol production, and the following downstream distillation sequences have been extensively investigated. Whereas, there are still no comprehensive comparison of the reported distillation processes in sight of the techno-economic feasibility. In this study, three alternative distillation sequences that contains a decanter and recycle loops are selected and compared by steady-state simulation. ABE condensates collected by ISPR, with different solvent concentrations and constituents, are considered as the feed stream of distillation. The impact of ABE ratio on energy consumption and techno-economics of the selected distillation sequences are analyzed. Results indicate the separation performances, including the energy requirement and economics, are highly influenced by the distillation sequence. Compared with other Scenarios, when feeding the extreme ABE constituents within the confidence interval, the sequence that consisted of three columns and a decanter with two recycle loops exhibits the lower energy requirement (7.99 MJ/kg) and TAC (4.15 × 106 US $/yr). The current work guides to the designation of suitable ISPR-distillation process in future works. • Different distillation sequences are compared for sequential ABE separation after ISPR. • The effect of feed ABE ratio on distillation performance is revealed. • Statistical analysis was used to determine the confidence interval of ABE constituents. • Static process simulation is carried out to compare different distillation sequences. • Energy requirement and total annual cost of distillation sequences are compared. [ABSTRACT FROM AUTHOR]