There is an increasing interest in using non-wood lignocellulosic materials for the production of wood-based medium density fiberboard (MDF). Agave durangensis Gentry bagasse is a waste product produced in large quantities in the mezcal industry. This study evaluated the incorporation of A. durangensis bagasse fibers (ADBF) to elaborate MDF wood-based panels. Three types of panels with different ratios (wood fibers: bagasse fibers) were investigated. The ratios evaluated were 100:0, 90:10, and 70:30. The density profiles, water absorption, and thickness swell of the panels were determined, as well as the modulus of elasticity (MOE), modulus of rupture (MOR), and internal bond (IB), according to the ASTM D1037-06a standard. The results were compared to the ANSI A208.2-2016 standard. The effect of the addition of ADBF on the properties of the panels was analyzed. Density profiles were comparable among the three types of panels, while water absorption, thickness swelling, MOE, MOR, and IB were similar between panels with ratios of 100:0 and 90:10. Panels with 10% and 30% of ADBF meet the minimum ANSI requirements for quality grade 115. It is feasible to use up to 30% of ADBF in the manufacture of wood-based MDF panels.

El carbón vegetal elaborado en México proviene de diferentes especies y procesos, por lo que sus características varían ampliamente. El objetivo de este trabajo fue caracterizar el carbón vegetal producido en el Norte-Centro de México, según normas internacionales de calidad y energía. Se recolectaron al azar tres bolsas de nueve procedencias comerciales de carbón de mezquite (Prosopis sp.), ébano (Ebenopsis sp.) y encino (Quercus sp.). Se determinaron granulometría, contenido de humedad, material volátil, carbono fijo, poder calorífico y los elementos Mg, Ca, Cu, Zn y Fe. Los datos se sometieron a un análisis de varianza en un diseño completamente aleatorio con cuatro repeticiones por bolsa y comparación de medias con la prueba de Tukey. Predominó el tamaño 20 mm > X ≤ 50 mm, únicamente dos procedencias presentaron fragmentos > 100 mm. Los valores promedio fueron: contenido de humedad 5.1%, material volátil 25.9%, ceniza 6.3% y carbono fijo 62.7%. El poder calorífico más alto fue 27 669 kJ kg-1 y se registraron valores elevados de Ca (177 266.6 mg kg-1) y Mg (20 263.3 mg kg-1). Las procedencias 5, 7 y 8 presentaron más carbono fijo. La variación se relacionó con la especie y procedencia. Es necesario mejorar la calidad del carbón producido en México considerando granulometría, carbono fijo y poder calorífico, así como niveles bajos de contenido de humedad, material volátil y cenizas. La evaluación constante de estos componentes permitirá definir acciones para mejorar la calidad del carbón producido en México y facilitará su comercialización en mercados internacionales.

The industrial production and commercialization of distilled beverages from Sotol plants (Family: Asparagaceae, Subfamily: Zolinoideae and Genus: Dasylirion) has witnessed a steady growth in recent decades; this condition involves a greater use of the raw material that comes almost exclusively from natural populations, which could compromise the sustainability of the marginalized areas of Northern México. In the present work, habitat availability was evaluated for the presence and use of the species; Dasylirion wheeleri (S. Watson ex Rothr.), Dasylirion cedrosanum (Trelease), and Dasylirion durangense (Trelease) in México, considering different scenarios of climate change. For this purpose, we used the niche’s spatial analysis from a correlative approach. The results show that under the current climate, the species studied have a predominantly low habitat suitability in the central region of the Chihuahuan desert, with D. cedrosanum being the species with the lowest suitability. For the year 2050, a slight increase in the habitat suitability is expected only for D. durangense and D. wheeleri. This suggests that D. cedrosanum could be considered as the species with the greatest vulnerability to the possible climatic variations generated by global climate change. Likewise, the analysis of the results indicates that D. durangense is the one who has the greatest potential for use; however, it is necessary to consider that many of its populations may be climatically stressed and an inappropriate use could put them at risk.

Walnut tree (Carya illinoensis (Wangenh.) K. Koch) is a plant species showing ecological, social, and economic importance in México. The objective was to determine biomass productivity and to characterize the raw material and biomass briquettes obtained from walnut thinning pruning. The variables evaluated were tree total height (TH), fresh biomass (FB) and dry biomass (DB) per hectare (kg ha⁻¹). Briquettes were made by using the biomass obtained in both orchards. Laboratory tests for original biomass included moisture content (MC), ash content (AC), volatile matter (VM) and fixed carbon (FC), as well as high heating value (HHV). Briquette studies also included diameter (D), weight (W), length (L), volume (V), density (Ds), and HHV. The data were analyzed by using descriptive statistics and analysis of variance (ANOVA) under a completely randomized design with factorial arrangement. Thinning pruning in walnut orchards provides 12 kg tree⁻¹ (998 kg ha⁻¹) of dry biomass, with acceptable levels of AC ≤ 5%, FC (75 to 76%), VM (18.7 to 19.7%) and HHV (16.2 to 16.7 MJ kg⁻¹). The briquette international quality standards were fulfilled: MC≤ 10%, AC ≤ 5% and HHV > 18 MJ kg⁻¹. The integrated use of walnut residues reduces the management problems registered during nut production and the sustainable options to generate bioenergy will be expanded.

Biomass revalorization is a worldwide trend which can contribute to diversifying the energy sector and to obtaining added value products. The objective of the present review is to discern potential sources of biomass and their corresponding alternatives for transformation, with a particular emphasis on energy generation within the Mexican highlands and semi-desert regions. Methodologically, this review was conducted by reviewing various search engines, identifying articles related to energy production, the transformation processes, and the obtained product, establishing the relevance of each contribution, and including the information that was deemed pertinent. From this information analysis, it was found that most of the studies are conducted at theoretical and laboratory levels; then, scientific knowledge has been generated in this topic. However, low interaction with the social and industrial sectors is observed. It is required to develop strategies to transfer the generated knowledge and to scale up the studied transformation processes to generate ecological, economic, and social benefits. According to the information obtained it can be concluded that the agricultural and forestry sectors in the highlands and semi-desert regions of Mexico hold significant promise for generating bioenergy via the utilization of residual biomass, including stubble, straw, branches, stems, and sawdust. Moreover, the implementation of these sophisticated techniques for the conversion of residual biomass into biofuels and other forms of bioenergy contribute to the improvement of the adverse effects associated with the use of fossil fuels while fostering a more environmentally sustainable economy.

La productividad de biomasa en especies de crecimiento rápido es una de las mejores alternativas para la elaboración de biocombustibles dendroenergéticos. Uno de los pretratamientos de la biomasa más importantes es el peletizado y con esto aumenta el poder calorífico. El objetivo de este estudio fue evaluar la calidad de pélets de ocho especies dendroenergéticas de crecimiento rápido. Las especies evaluadas fueron Eucalyptus globulus, Pinus greggii, Populus alba, Acacia retinoides, Ricinus communis, Populus deltoides, Pennisetum sp. y Salix sp. El diseño experimental fue completamente aleatorio; las especies analizadas como tratamientos. Con los datos se realizó un ANDEVA y las medias de los tratamientos se compararon con la prueba de Tukey (p≤0.05). Las variables evaluadas fueron: contenido de humedad (CH), cenizas, material volátil (CV), carbón fijo (CF) y poder calorífico superior (PCS); diámetro, longitud, peso, volumen, densidad a granel (DG) y densidad básica (DP); índice de resistencia, pérdida de biomasa y friabilidad (F). Las diferencias entre especies fueron significativas (p ≤0.05), para todas las variables. Ocho de las nueve especies cumplieron con valores mínimos del PCS (19.2 MJ kg-1 y 20.1 MJ kg-1) requerido en normas internacionales de calidad en pélets (18.0 MJ kg-1). Los pélets de ocho especies mostraron las dimensiones solicitadas en las normas de calidad. Todas las especies presentaron densidad aceptable, con base en la norma internacional. En la densidad básica se observaron valores altos y significativos en Pennisetum sp (1.4 g cm-3) y Pinus greggii (1.4 g cm-3), mientras que P. deltoides registró el valor más bajo (1.0 g cm-3). En las pruebas de resistencia, los pélets de P. greggii mostraron valores altos para el número de partes al rompimiento (2.4) y pérdida de biomasa (41.6%); así como valores bajos de friabilidad (0.45). Los pélets obtenidos a partir de la biomasa de las especies evaluadas cumplieron con los estándares internacionales de calidad.