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There has been an increasing interest in the conversion of biomass to biofuels, energy, and chemicals due to an increase in meeting environmental demands and price and decrease in the potential ava...

Production pathway sustainability assessment is an important step in promoting sustainability characteristics during early process design. This work proposes distillation intensified alternatives for the recovery of nylon industry effluents. The waste stream contains n-pentanol, cyclohexanone, and cyclohexene oxide (light oil). These products in their pure state are high added-value products. The generation of intensified alternatives is based on the inclusion of thermally coupling, column section movement, and column section elimination. All the alternatives are evaluated in various metrics that guarantee the sustainability of the process; Mass Intensity, E-Factor, Greenhouse Gas Emissions, Total Annual Cost, Controllability, and Inherent Safety. As a result, the intensified alternative with a thermal coupling turned out the most balanced process in light of sustainability indicators with energy requirements of 4.87 MJ/kgproduct and important improvement in sustainability indexes.

Butanol is an interesting biofuel and a product precursor, that could be obtained with acetone and ethanol via fermentation. The biofuels production has been identified as not economically competitive, thus, the parallel production of high value-added products, such as xylitol, could be an alternative to improve the profit. Xylitol can be produced from xylose, which might be considered as a coproduct in a second generation biorefinery. This study presents a systematic biorefinery process design for the simultaneous acetone, butanol, ethanol (ABE) and xylitol production, based on experimental and simulation approaches. Experiments were performed for the pretreatment of sugarcane bagasse and ABE fermentation. The simulation part used the experimental results and experimental data from literature, to perform rigorous calculations of the ABE and xylitol production process. The economic analysis (EA) was performed relying on some indicators such as, the net present value (NPV) and payback period (PBP); EA includes several scenarios for producing only ABE and some scenarios for simultaneous ABE and xylitol production. The results showed that the combined butanol and xylitol production could reduce by 17% the selling price of butanol, compared with only producing butanol. The study also included the combustion of residual solids and carbon dioxide depletion analyses. This approach illustrates the opportunity to perform a rigorous techno-economic analysis, to identify the feasibility of the process at industrial scale, based on realistic data. This approach was implemented for ABE and xylitol production, but it can be used to any other bioproduct.

Este trabajo presenta los resultados obtenidos a escala de laboratorio para el aprovechamiento de la pulpa de café (residuos), en el proceso de beneficio húmedo aplicando el concepto de biorrefinería. Los resultados mostraron que es posible tratar este residuo mediante procesos fermentativos y obtener bioetanol separado por medio de la destilación simple con un contenido en alcohol entre 3,85% al 6,90% por cada 250ml de biomasa tratada en condiciones ambientales. Se observó en todos los ensayos que una variable importante es el tiempo de fermentación y la estructura inicial del residuo ya que esto influye sobre el rendimiento obtenido en términos del bioalcohol producido. Este trabajo forma parte del estudio preliminar para la implementación del concepto de biorrefinería a los residuos generados en el beneficio húmedo del café. La búsqueda de alternativas que permitan el aprovechamiento de los residuos del café constituye una problemática actual. Estos residuos al no ser tratados, por lo general son vertidos a las fuentes hídricas y en ocasiones utilizados como enmiendas agrícolas en los cultivos, lo cual puede causar graves problemas de contaminación. Por este motivo es necesario realizar investigaciones en este campo que permitan su tratamiento o aprovechamiento integral.

The transport sector increasing energy demand has encouraged the search for alternative technologies for biofuels production with lower manufacturing costs and higher process efficiency and environmental performance. Lignocellulosic biofuels are equivalents to petroleum products and can be adapted to meet the properties requirements of current engines. However, their major disadvantages are the high production costs and the lack of infrastructure. In this work, the focus is on the implementation of a multi-objective optimization methodology for synthesis of novel intensified biomass-to-liquid (BtL) technologies with lower environmental impact and costs, as well as higher process safety and efficiency. A novel optimization methodology is applied to two process configurations that were synthesized in a previous work [1], in which the evaluation of a BtL processing superstructure under different economic constraints and product profiles scenarios was performed. From the configurations, the two case studies with higher production of both gasoline and diesel were selected for this work. For the synthesis of intensified BtL technologies, the optimal separation units’ design parameters that meet the combination of economic, safety and environmental indexes, and two green chemistry metrics were selected. By applying the methodology, the optimal intensified process presents a higher return on investment of 22 (%/y) compared to 18 (%/y) for the base case flowsheet.

In recent years, electricity demand has been increasing, according to the International Energy Agency, the energy sector is the biggest producer of greenhouse gas emissions (CO2), having terrible environmental consequences. Various alternatives have been sought to reduce CO2 emissions, highlighting the implementation of CO2 capture and storage plants. In this work, it is shown an environmental and energetic analysis of a CO2capture plant coupled to a power plant. The analysis considered two different operating cases with different fuels in the power plant each case: biogas, coal, non- associated gas, and associated gas. The first one considers a constant fuel feed flow in the power plant. The second one, considers a constant energy demand. The results indicate that, for the first case, the fuel with the lowest environmental impact was the non-associated gas with 2.14 kEcopoints and 1083 MJ per kg of CO2 recovered. For a constant energy demand, the fuel with the lowest environmental impact was the biogas with 0.57 kEcopoints and 193 MJ per kg of CO2 recovered. For the systems here considered, those processes working with associated and non-associated gases remain the most efficient in terms of net energy produced.

Methyl ethyl ketone (MEK) is a widely used chemical in the industry. Most of the MEK uses are directly related to industrial application; however, recent studies suggest the use of MEK as a possible fuel for spark-ignition engines. The industrial process to produce MEK is performed through the hydration of butylene and the dehydration of that alcohol. Butylene is produced from oil cuts. However, petroleum is a recognized finite resource and is pointed out as a major cause of environmental issues. An alternative to improve a process is process intensification (PI). In this work, an intensified alternative to produce MEK from 2,3- Butanediol is proposed. 2,3-Butanediol might be produced by a fermentation process based on renewable biomass. The intensified alternatives consist of a reactive distillation column, an extractive distillation column, and three conventional distillation columns. The novel alternatives produce and purify MEK, 1,2-BD, 2MPL, and water, from 2,3-BD using calcium phosphate as catalyst were modelled in Aspen Plus. To evaluate the intensified alternative, it was considered the energy requirements per kilogram of MEK, conversion, selectivity as well as an environmental impact index, the greenhouse gas emissions. The RD column resuzlted in a conversion of 99.86 % and a selectivity for MEK of 44 %. After evaluation, the direct scheme resulted as the most promising one, with energy requirements of 2790 kcal/kgMEK (11.6 MJ kg/MEK). Regarding the environmental impact, the direct scheme reported 7.07 tCO2/h of greenhouse gas emissions.

The use of biomass has been associated mainly with the energy or biofuels. However, the production of high value-added products such as chemical building blocks, show a feasible alternative. However, the coordination of all the players within a market is complex because is necessary ensuring that the balance of profits generated will be greater than production and logistic cost, becoming an optimization problem. Therefore, we propose a coordination framework for managing lignocellulosic biomass from agricultural residues in a scalable manner by orchestrating biomass exchange, transportation, and transformation into value-added products, specifically: Levulinic acid and furfural. In the proposed framework, suppliers and consumers of biomass and derived products as well as transportation and technology providers bid into a coordination system that is operated by an independent system operator. All locations, prices for all biomass types and derived products are obtained by the operator by solving a dispatch problem that maximizes the social welfare and that balances supply and demand across a given geographical region. Through the coordinated framework, cleared transportation flows, locations and technologies involved are obtained to meet demand. The production of Levulinic acid was 330 Kt/year and 394 Kt/year of Furfural. Which represent 3% of global demand of raw materials for methyltetrahydrofuran. On the other hand, the benefit generated to biomass suppliers exceeds $27 million / year, which would represent an increase in social welfare in the area, specifically to farmers. The framework allows to identify guidelines of the market behaviour considering all market players, with these guidelines is possible propose actions to be able to project a more competitive market for all products and that favors all market players.

2,3-Butanediol is a promising chemical due to its several applications. Nowadays, 2,3-Butanediol is produced by a chemical process. However, it is also produced by microbial production. Several metabolic strategies attempt to enhance the production of 2,3-Butanediol; yet, the recovery of 2,3-Butanediol from the fermentation broth is yet a challenge due to its low concentration. In this manner, a recovery process with cost and energy savings is required. Moreover, a wider point of view is also necessary since current needs involve a process with low environmental impact and high inherent safety. In previous work, the inherent safety was not calculated in early-stage design, which may further lead to misleading risk assessment. In this work, the inherent risk will be approached at early stages at the same time that economic and environmental issues. With this in mind, this paper presents the synthesis and design of some alternatives to purify 2,3-Butanediol based on distillation, those alternatives are synthesized in such way that are obtained as results thermally coupled, thermodynamically equivalent and intensified sequences. Additionally, a dividing wall column scheme was also designed and optimized to compare its performance with the other schemes. The alternatives were designed and optimized considering three objective functions: the total annual cost as an economic index, the eco-indicator 99 as an environmental index, and the inherent risk of the process (analyzed as individual risk). In general terms, the intensified alternative presented 15% reduction of the TAC and 14% of the environmental impact. Moreover, the same alternative presented the lowest inherent risk with a reduction about 50% in comparison with the reference alternative.

Inherent safety and control properties of a reactive distillation column for the production of tetraethoxysilane are compared with those of a conventional process based in a reactor-distillation co...

In the last decades, the need of cleaner and renewable fuels has increased the use of alcohols to power internal combustion engines. The ABE (acetone–butanol–ethanol) method to produce purified biobutanol and bioethanol is the most known and well-studied method to produce those alcohols. Nevertheless, it is not yet clear how the bioethanol’s content in the biobutanol stream could affect the engine’s biofueled performance. Thus, this study focuses on (1) the performance of an internal combustion engine and (2) on the different compositions of n-butanol/ethanol mixtures, up to 20 vol%, to assess the operative issues of the use of both alcohols instead of pure n-butanol. In order to get the most reliable results of the engine’s performance, we conducted three different experiments for each alcohols’ composition, including conventional gasoline testing as reference. The experimental tests were carried out in a CT 150 Internal Combustion Engine Basic Module and conducted at various speeds—from 700 to 1500 rpm—resulting in load variation. In general, the changes in the composition of ethanol in n-butanol do not seem to affect the performance of the engine considerably, as variations occur at an approximate rate of 3.7% in effective power, 3.3% in torque and 5.4% in specific fuel consumption.