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The sugarcane sector in Brazil has undergone a major modernization in the last thirty years. Embracing the biorefinery concept, this sector is investigating bioproduct diversification and mostly putting a lot of effort and investment on second generation ethanol production. In this context, the investigation of the integration of a third generation biofuel production using microalgae to the sugarcane biorefinery seems an important starting point. This study evaluates the integration of microalgae growth and processing to a sugarcane biorefinery producing first and second generation ethanol using process simulation tools. Microalgae are cultivated using CO2 produced during fermentation of ethanol and it is processed using supercritical fluid extraction technology in order to obtain lipids rich in high added-value compounds, carotenoids. The results showed that the integration of microalgae biomass processing without previously drying with the sugarcane biorefinery is not attractive from the thermo-economic point. When considering the extraction of dried microalgae the extraction process could be thermal integrated to the sugarcane biorefinery producing ethanol without the need of buying external fuel. The amount of CO2 used as solvent to the supercritical fluid extraction was the main factor that influenced the economic viability of the process. When microalgae pretreatment by cell disruption or co-solvent extraction was considered, it was possible to decrease the amount of CO2 used in the process and an increase in process yields was consequently achieved. The use of a co-solvent in the extraction increased in 1.4 and 2.4 times lipids and carotenoids extraction, respectively, and presented a lower investment when comparing with microalgae extraction without cell disruption.

Supercritical fluid extraction has been employed as a green alternative for the obtaining of extracts provided of bioactive constituents from defatted Assai waste. The effects of process parameters on the resulted overall extraction curves were evaluated using a spline model, which adjustable parameters used to analyze the extraction behavior were the time span periods for the constant and falling extraction rates, i.e., tCER and tFER, and the extraction rate for the constant extraction period, MCER (or b1). The mathematical modeling was performed using an alternative algorithm implemented in MS Excel, which was able to provide reliable fittings comparable to SAS software. Although no report has been found to be compared to our economic evaluation findings, the costs of manufacturing (26.20–4.88 USD/kg extract) obtained in this work are competitive in the market, since the selling price of similar products worldwide is over 80.00 USD/kg of extract.

In this study, we discuss the difference regarding thermo-economic and environmental (water intake) aspects between two methods of biomass hydrolysis. A thermo-economic model was developed using Aspen Plus® and MATLAB software in order to analyze the energy efficiency, as well as, the economic impact of the hydrolysis process integrated into a traditional ethanol production process from sugarcane. The study aimed at comparing the enzymatic route for sugarcane bagasse ethanol production with the supercritical water-based one. The use of supercritical water hydrolysis (SCWH) process showed promising results, being the process energetically self-sufficient when considering pumping of liquid streams with biomass content of 20% and the decompression of the steam separated after SCWH with a turbine, in order to produce electricity. In terms of economics, the biorefinery concept using enzymatic route presented the highest production costs due to the higher total investment cost and the cost for the raw materials, which is 14% higher than the biorefinery with SCWH, giving a payback time for the investments of 7.5 years, meanwhile 6.2 for the SCWH route. Also better results were obtained for water intake for the SCWH option, being lower than the maximum permitted for a new investment on the Brazilian sugarcane sector.

The present study evaluates a sugarcane biorefinery producing ethanol through juice fermentation and methanol via gasification of sugarcane lignocellulosic residues and liquid fuel synthesis. Two technologies of gasification named entrained flow and circulating fluidized bed are compared. Flowsheet modeling and thermo-economic analysis methods are applied, followed by a multi-objective optimization based on a genetic algorithm. The optimum Ethanol–Methanol biorefinery design options are compared with other previously studied sugarcane biorefineries. The results show that the biorefinery's energy efficiency increases significantly with the integration of a methanol production plant in a conventional ethanol distillery. The configuration using an entrained flow gasifier presents lower conversion efficiency than the one using a circulating fluidized bed gasifier. However, for the entrained flow gasifier configuration, the size of the methanol production process could be bigger since more heat is available for the ethanol process favouring the integration with the ethanol plant. Higher energy efficiency due to increase of methanol production leads to a higher total investment for both gasification technologies. The cost analysis shows that the calculated methanol production cost is 30% higher than its current market price. Environmental incentives for biofuels could change this scenario but are not in the scope of this study.

Brazilian ginseng extracts are considered as functional ingredients to promote health benefits due to its bioactive properties. The present study aims at studying a two-step intensified extraction process that operates at ambient pressure in order to recover Brazilian ginseng roots bioactive compounds. The intensified process consists in a sequential extraction system using ethanol followed by water, envisioning the improvement of the overall extraction yield of the process to make it feasible. A technical-economic analysis of the proposed process was assessed through the use of computational simulation tools. The intensified process was compared to a simple extraction process using only ethanol or water as extracting solvents. The results showed that the lowest payback time for the investment is achieved not by minimizing process cost but at maximizing beta-ecdysone production. Economic performance indicators of income statement and profitability ratios showed that, even with higher investment cost, the intensified process presented higher economic attractiveness than the single step extraction processes using ethanol or water.

The effects of several operational parameters (pressure, temperature, CO2 flow rate, solution flow rate, injector type, and concentration of solute in the ethanol solution) during Supercritical AntiSolvent (SAS) precipitation process on the energy consumption cost per unit of manufactured product were investigated using experimental design technique. In this work, two different injectors were used. A completely randomized experiment would eventually require a modification of the apparatus after each experimental run. To avoid this, the experimental runs were done accordingly with a split-plot experimental design. For this study, Ibuprofen sodium salt was used as a model solute, ethanol was used as solvent, and CO2 was used as antisolvent. This supercritical fluid-based has been used successfully for several food and pharmaceutical applications since the production of small micro- and nanometer-sized particles have attracted growing interest in these industries. Focusing on energy saving, an SAS precipitation process was simulated using the SuperPro Designer simulation platform. The effect of temperature versus concentration of ethanolic solution and pressure versus solution flow rate interactions on the energy consumption cost per unit of manufactured product was demonstrated. The lowest estimated energy cost per unit of manufactured product was obtained using an ethanolic solution of 0.04 g mL−1 at 12 MPa of pressure and a solution flow rate of 1 mL min−1. This result was independent of the temperature. Thus, the present work reports a systematic energetic-economic study of the supercritical antisolvent micronization process, aiming increase knowledge about this process and its further incorporation by the food and pharmaceutical industries.

This work consists of the steps for the assembly of a Supercritical Antisolvent Precipitation laboratory equipment and evaluation of the parts acquisition costs. A flow diagram with all components was developed, a complete list of all necessary components was presented, and an estimate of the acquisition of these parts in Brazil was reported. The stages of construction along with the importance of each component in the equipment were discussed. An equipment designs were presented as a result of the current work that serve as a basis for consulting future work on the development of new equipment.

High Turbulence Extraction Assisted by Ultrasound combined with Supercritical Antisolvent Fractionation (SAF) was done to intensify the recovery of bixin and phenolic compounds from semi-defatted annatto seeds. Annatto seeds are extensively used due to its colorant properties and bioactive potential in human health. Modifications were performed in the SAF experimental apparatus in order to prevent losses of product. Results show that supercritical fractionation resulted in particle yields between 72.2–80.5%, 20–50% phenolics, and 66% bixin.

Background: Cogeneration systems using biomass materials as woodships, agricultural and municipal solid waste, are well known and used in different places of the world. Today Brazilian sugarcane bagasse is an important energy source to these industries, most of them are self-sufficient in energy consumption and some generate energy surplus that is sold to the grid. There is a tendency forenlarging the electricity production at these industries and it is expected that in short to mid-term electricity produced from bagasse could become a product as important as ethanol or sugar. Methods: This study provides an overview of scientific papers and patents regarding the current situation of biomass cogeneration in Brazil and future prospects, focusing on the use of advanced cogeneration systems with integrated gasification combined andsupercritical steam cycles. Results: The results showed that much can still be done to improve the energetic efficiency at this sector. The current situation shows that although many companies are self-sufficient in terms of electricity just a few are able to sell electricity to the grid. There are many opportunities to better use the sugarcane bagasse and other biomass residues for energy production, from minor changes as improvements at the burning system to advanced power generation solutions. The minor changes can be accomplished with lower investment costs but with significant results for energy generation. Conclusion: The use of advanced power generation solutions as biomass gasification and supercritical steam cycles, proved to be highly efficient in energy production, generating a great electricity surplus.

The present study evaluates the use of supercritical fluid technology, particularly supercritical water gasification (SCWG), to add value to residues from a sugarcane biorefinery that produces first and second generation ethanol. This case study aims at elucidating how process system engineering tools such as thermal process integration, life cycle analysis, economic evaluation and multi-objective optimization can contribute to minimizing some future challenges of the industrial implementation of supercritical fluid- based technologies, which were discussed in the Workshop on Supercritical Fluids and Energy – SFE’13. In addition, this case study exposes future perspectives in terms of the requirements to further develop this field. The optimized solutions of the evaluated case showed that the SCWG process increases the overall efficiency of the process in terms of energy and carbon fixation. It decreases the CO2 equivalent emissions and it leads to a thermally self-sufficient process. The economic analysis showed a high investment cost but a feasibility of using the current market prices for the produced fuels and electricity.

The construction of a supercritical fluid extraction (SFE) plant inside or in close proximity to a sugarcane biorefinery producing first and second generation ethanol demonstrated to be very promising, increasing the economic potential of the SFE process in up to 57 %, since the SFE plant could use directly the ethanol, CO2, heat, and electricity already available, with lower prices. In this study, Brazilian ginseng roots were used as model bioactive compounds source and first the statistical influence of the extraction conditions including pressure (10–20 MPa), temperature (323–363 K), and CO2/ethanol proportion ratio (90:10, 50:50, and 0:100 %, w/w) on the β-ecdysone content in the extracts was experimentally evaluated and compared with literature results. SFE process evaluated experimentally at the present study showed higher selective extraction for β-ecdysone from Brazilian ginseng roots, providing an extract with up to 2.16 times higher β-ecdysone than the results obtained in previous studies. Thermal integration of the SFE process diminished energy requirements of the process, resulting in a reduction of cold utility requirement of 87 % and a final electricity demand of 7.5 kWh/g of β-ecdysone in the extract. In a situation in which the Brazilian ginseng roots price was increased to 4.71 USD/g, only the SFE integrated with the biorefinery solution would be economically feasible. Finally, the selling of the ginseng roots leftover could be an interesting answer to increase the economical attractiveness of the integrated SFE process to the biorefinery.

Commercial simulator Aspen Plus was used to simulate a biorefinery producing ethanol from sugarcane juice and second generation ethanol production using bagasse fine fraction composed of parenchyma cells (P-fraction). Liquid hot water and steam explosion pretreatment technologies were evaluated. The processes were thermal and water integrated and compared to a biorefinery producing ethanol from juice and sugarcane bagasse. The results indicated that after thermal and water integration, the evaluated processes were self-sufficient in energy demand, being able to sell the surplus electricity to the grid, and presented water intake inside the environmental limit for São Paulo State, Brazil. The processes that evaluated the use of the bagasse fine fraction presented higher economic results compared with the use of the entire bagasse. Even though, due to the high enzyme costs, the payback calculated for the biorefineries were higher than 8 years for all cases that considered second generation ethanol and the net present value for the investment was negative. The reduction on the enzyme load, in a way that the conversion rates could be maintained, is the limiting factor to make second generation ethanol competitive with the most immediate uses of bagasse: fuel for the cogeneration system to surplus electricity production.

Producción Científica, Recently, supercritical fluid extraction (SFE) has been indicated to be utilized as part of a biorefinery, rather than as a stand-alone technology, since besides extracting added value compounds selectively it has been shown to have a positive effect on the downstream processing of biomass. To this extent, this work evaluates economically the encouraging experimental results regarding the use of SFE during annatto seeds valorization. Additionally, other features were discussed such as the benefits of enhancing the bioactive compounds concentration through physical processes and of integrating the proposed annatto seeds biorefinery to a hypothetical sugarcane biorefinery, which produces its essential inputs, e.g., CO2, ethanol, heat and electricity. For this, first, different configurations were modeled and simulated using the commercial simulator Aspen Plus® to determine the mass and energy balances. Next, each configuration was economically assessed using MATLAB. SFE proved to be decisive to the economic feasibility of the proposed annatto seeds-sugarcane biorefinery concept. SFE pretreatment associated with sequential fine particles separation process enabled higher bixin-rich extract production using low-pressure solvent extraction method employing ethanol, meanwhile tocotrienols-rich extract is obtained as a first product. Nevertheless, the economic evaluation showed that increasing tocotrienols-rich extract production has a more pronounced positive impact on the economic viability of the concept., Fundação de Amparo à Pesquisa do Estado de São Paulo (Brasil) -FAPESP (processes 2013/18114-2; 2015/06954-1), Ministério da Educação (Brasil) - CAPES (process 7545-15-0), Conselho Nacional de Desenvolvimento Científico e Tecnológico (Brasil) - CNPq ( grant 301301/2010-7), Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) y Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) - (Brasil) - (Procesos 2012/10685-8; 2015/13299-0)

Glycerol is an important by-product of biodiesel production. It is used in many industrial segments, but the increasing production of this chemical has become an issue of concern. Many studies have been done to give new applicability to this product; a promising field is the usage of glycerol for energy production. Therefore, this study evaluates the technical and economic feasibility of a new and potential proposal at the national level, the generation of electricity and heat, through a cogeneration system using glycerol. The results demonstrate the viability of this proposal, since the payback on capital invested obtained was approximately 4 years, with the possibility of reduction to 3 years when installed in regions with low infrastructure.

In the present study, the software Aspen Plus® was used to analyse two different systems for CO2 recycle in a SFE process for extraction of more polar compounds using ethanol as co-solvent, the most common co-solvent used due to its environment-friendly nature. The extraction process of β-ecdysone from Brazilian ginseng roots was considered as example in the computational simulations. The first CO2 recycle system, named Recycle A, considered the compression of the CO2 separated in the second flash to the recycle pressure assumed at the first flash tank, its cooling to 25 °C and recirculation, while the second recycle system, named Recycle B, considered the cooling and pumping of the CO2 separated in the second flash, its heating to 25 °C and recirculation. The best techno-economic condition to operate the recycling step would be using Recycle A at 40 bar and 30 °C considering a stand-alone SFE process; and using Recycle B at 40 bar and 40 °C, considering this process in close proximity of a hypothetical sugarcane biorefinery. Therefore, these results suggest that the selection where would be located the SFE plant should be taken into account during the first steps of the process design.