• Energy Research

This work aims to evaluate from an energy and economic perspective the production of essential oil, pectin, and biogas as alternatives to valorize orange peel waste. For this, the chemical characterization, extraction of essential oil, and pectin of industrial of this residue samples were done. Moreover, the remaining solid was used to produce biogas. The experimental results were used as input data to simulate the biorefinery. The mass and energy balances from the simulation were used to perform energy and economic analysis of the biorefinery system analyzing the net present value and processing scale as determining factors. Also, mass and energy efficiency indicators were applied to evaluate the performance of the biorefinery. The experimental essential oil, pectin extraction, and biogas yields 0.61% w/w (wet basis), 10.35% w/w (wet basis), and 89.39 Nm3/ton OPW mL biogas/g VS with a CH4 content of 66.73% (59.6 Nm3/ton OPW), respectively. The mass and energy indicators show a good performance of the process in terms of mass and energy efficiency indicators. Moreover, the economic analysis leads to observe that the proposed biorefinery is only feasible at low processing scales. In a conclusion, orange peel waste is a potential feedstock to obtain value-added products such as essential oil and pectin and energy vectors such as biogas in an energy and economic feasible way at low scales allowing the implementation of small-scale integrated biorefinery systems.

Sustainability of products and services has become a compulsory requirement and an essential requirement for organizations, governments, markets and society in general. Among the various ways of measuring sustainability that have been developed, those based on life cycle thinking provide one of the frameworks for assessing the potential impacts of products and services. However, despite sustainability of triple bottom line parameters (ecological, financial and social), the life cycle assessment is the most mature and prominent available tool. In addition, integration methodologies have come up, like life cycle sustainability assessment (integrating the three sustainability dimensions) and life cycle engineering (including the technical or functional aspect). The application of these methodologies to emergent materials and technologies represents a huge challenge, because there is lack of proper indicators, lack of information and contradictory information is common. This is the case of biocomposites, built with nature-based materials harvested in a myriad of ways in several regions of the globe. So, this paper presents a systematic literature review about the research done on the realm of sustainability assessment methods application to biocomposites. It reveals knowledge and information gaps to apply these methodologies. The integration of the existing methodologies is proposed as a way to allow a holistic sustainability assessment of biocomposite materials.

One of the main drawbacks for using lignocellulosic biomass is related to its recalcitrance. The pretreatment of lignocellulosic biomass plays an important role for delignification and crystallinity reduction purposes. In this work rice husk (RH) was submitted to supercritical pretreatment at 80°C and 270 bar with the aim to determine the effect on lignin content, crystallinity as well as enzymatic digestibility. The yields obtained were compared with dilute sulfuric acid pretreatment as base case. Additionally a techno-economic and environmental comparison of the both pretreatment technologies was performed. The results show a lignin content reduction up to 90.6% for the sample with 75% moisture content using a water-ethanol mixture. The results for crystallinity and enzymatic digestibility demonstrated that no reductions were reached. Supercritical pretreatment presents the best economical and environmental performance considering the solvents and carbon dioxide recycling.

Abstract Many countries are promoting the use of biodiesel as a direct replacement for, or blend stock component with petroleum based diesel fuel using policy instruments that aim to gradually increase the use of vegetable oil biodiesel–diesel ratio from the current (or inexistent) blend to values among 15–20% by an specific upcoming year. For the particular use of palm oil as biomass raw material in the diesel–palm oil biodiesel (Diesel–POB) blend that goal could bring some difficulties because the high content of saturated fatty acids in POB could confer a problematic high cloud point to the fuel mixtures. On the other hand, the use of castor oil biodiesel in the blends could lower the cloud point value but, simultaneously, increase the viscosity of the diesel–biodiesel blends. In this article there were evaluated three properties (viscosity, cloud point and flash point) of binary mixtures castor oil biodiesel (COB), palm oil biodiesel (POB) and diesel fuel. It was also measured the cloud point for some ternary bends of Diesel/POB/COB. It was found that diesel–castor oil biodiesel (Diesel COB) blends showed appropriate and approximately the same cloud point temperatures when the biodiesel concentration in those mixtures was under 40% in volume. The use of palm oil biodiesel–castor oil biodiesel (POB COB) blends to obtain a type of pure biodiesel with both low cloud point and viscosity was not a practical option. Experimental data were also compared with the predictions of different published models for diesel–biodiesel mixtures. The general thermodynamic expressions used for estimation of viscosity and cloud point for liquid mixtures showed lower deviations from experimental values properties predictions from other proposed empirical models.

Appropriate waste management in emerging economies like Colombia should be an asset for the overall sustainability. In the Orange Peel Waste case, incineration and Anaerobic Digestion are challenging solutions for the orange juice agro-industrial sector for avoiding the landfill, which is the conventional practice. However, these alternatives should be assessed in order to determine their feasibility. This paper aims to understand if incineration and Anaerobic Digestion are potential alternatives to landfill form a techno-economic and environmentally perspective. To this aim, a comparative Life Cycle Assessment was carried out in four scenarios. In the first scenario coal and landfill are used as source of energy and landfill disposal in the actual orange juice process. In the second scenario, the peels are incinerated to avoid landfill and reduce the need for coal. The third scenario includes the valorization of the peels by means of Anaerobic Digestion which produces biogas for the plant energy requirements. In the fourth scenario, apart from the energy from biogas, the digestate becomes a fertilizer for use in the orange crops. The results revealed that scenario III and IV are environmentally friendly options compared to Scenario I, but they incur higher costs than Scenario II. Carbon footprint found that 1.55 kg of CO2 are saving when coal substitution is reduced from 0.493 kg in SI to 0.279 kg in SII. Therefore, Scenario II is more suitable for the Colombian socioeconomic reality since Scenario II is not only techno-environmentally achievable, but also economically feasible. The methodology used in this case study could be applied to other countries or small and medium scale technologies and could also be useful for the scientific community, enterprises and policy-makers. The authors wish to acknowledge the financial support of the Fondo Regional de Tecnología Agropecuaria FONTAGRO [Contract:ATN/RF 16111RG, 2016] and of the Departamento Administrativo de Ciencia, Tecnología e Innovación, Doctorados Nacionales [Contract:727, 2015]. Also this article is the result of the work developed through the "Programa de investigación reconstrucción del tejido social en zonas de pos-conflicto en Colombia" [SIGP 57579] withthe research project "Competencias empresariales y de innovación para el desarrollo económico y la inclusión productiva de las regiones afectadas por el conflicto colombiano" [SIGP 58907]. Finally, the authors would like to express their appreciation to FLP Procesados Company for providing the data for the case study.