Kinetic analysis of manure pyrolysis and combustion processes

Due to the depletion of fossil fuel reserves and the environmental issues derived from their use, biomass seems to be an excellent source of renewable energy. In this work, the kinetics of the pyrolysis and combustion of three different biomass waste samples (two dairy manure samples before (Pre) and after (Dig R) anaerobic digestion and one swine manure sample (SW)) was studied by means of thermogravimetric analysis. In this work, three iso-conversional methods (Friedman, Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose (KAS)) were compared with the Coats-Redfern method. The Ea values of devolatilization stages were in the range of 152–170 kJ/mol, 148–178 kJ/mol and 156–209 kJ/mol for samples Pre, Dig R and SW, respectively. Concerning combustion process, char oxidation stages showed lower Ea values than that obtained for the combustion devolatilization stage, being in the range of 140–175 kJ/mol, 178–199 kJ/mol and 122–144 kJ/mol for samples Pre, Dig R and SW, respectively. These results were practically the same for samples Pre and Dig R, which means that the kinetics of the thermochemical processes were not affected by anaerobic digestion. Finally, the distributed activation energy model (DAEM) and the pseudo-multi component stage model (PMSM) were applied to predict the weight loss curves of pyrolysis and combustion. DAEM was the best model that fitted the experimental data.Debido al agotamiento de las reservas de combustibles fósiles y los problemas ambientales derivados de su uso, la biomasa parece ser una excelente fuente de energía renovable. En este trabajo se estudió la cinética de la pirólisis y combustión de tres muestras de residuos de biomasa diferentes (dos muestras de estiércol lácteo antes (Pre) y después (Dig R) de la digestión anaeróbica y una muestra de estiércol porcino (SW)) mediante análisis termogravimétrico. . En este trabajo se compararon tres métodos iso-conversionales (Friedman, Flynn-Wall-Ozawa (FWO) y Kissinger-Akahira-Sunose (KAS)) con el método de Coats-Redfern. Los valores de E a de las etapas de desvolatilización estuvieron en el rango de 152–170 kJ/mol, 148–178 kJ/mol y 156–209 kJ/mol para muestras Pre, Dig R y SW, respectivamente. En cuanto al proceso de combustión, las etapas de oxidación del carbón presentaron valores de E a inferiores a los obtenidos para la etapa de desvolatilización por combustión, estando en el rango de 140–175 kJ/mol, 178–199 kJ/mol y 122–144 kJ/mol para las muestras Pre, Dig R y SW, respectivamente. Estos resultados fueron prácticamente los mismos para las muestras Pre y Dig R, lo que significa que la cinética de los procesos termoquímicos no se vio afectada por la digestión anaeróbica. Finalmente, se aplicó el modelo de energía de activación distribuida (DAEM) y el modelo de etapa pseudo-multicomponente (PMSM) para predecir las curvas de pérdida de peso de pirólisis y combustión. DAEM fue el mejor modelo que ajustó los datos experimentales

NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics

Xenarthrans—anteaters, sloths, and armadillos—have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, 10 anteaters, and 6 sloths. Our data set includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the southern United States, Mexico, and Caribbean countries at the northern portion of the Neotropics, to the austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n = 5,941), and Cyclopes sp. have the fewest (n = 240). The armadillo species with the most data is Dasypus novemcinctus (n = 11,588), and the fewest data are recorded for Calyptophractus retusus (n = 33). With regard to sloth species, Bradypus variegatus has the most records (n = 962), and Bradypus pygmaeus has the fewest (n = 12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other data sets of Neotropical Series that will become available very soon (i.e., Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans data set. Please cite this data paper when using its data in publications. We also request that researchers and teachers inform us of how they are using these data