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This work evaluated the pyrolytic products from spent coffee residue pyrolysis in a fixed-bed reactor. The effects of the heating rate and temperature on the main pyrolytic products were investigated using a factorial experimental design. The average product yields obtained were liquid (49.45 wt%), char (26.45 wt%), and gas (24.05 wt%). Temperature was the most significant factor affecting product yield. Maximum devolatilization occurred at 823 K and 80 K/min, the same conditions that minimized the char yield. The spent coffee ground (SCG) decomposition occurred mainly due to a dehydration reaction, followed by decarboxylation. The heating rate and temperature directly influenced the production of phenols, and the formation of esters and ketones was favored at 723 K. Statistical analysis of the biochar element composition showed a carbon enrichment and a decrease in oxygen, hydrogen, and nitrogen contents at higher temperatures due to strong devolatilization. Char polarity and aromaticity were strongly affected by the temperature. The C/N ratios of the SCG chars (18.4–20.7) indicated that these chars are possible soil additives.

This study aimed to describe the component properties of adult stems of different species of bamboo through a literature review. The data of holocellulose (cellulose + hemicellulose), lignin, ashes content, total extractives contents, and elemental chemical composition of bamboo was compared with other lignocellulosic materials. In the final considerations, it was found that there is similarity in the average holocellulose content between the species and genera of bamboo, tree species, and other alternative materials that are used in industrial processes. The lignin content varied among tree species, bamboo, and alternative materials, wherein the bamboo presented the intermediate value. The biomasses show hydrogen/carbon ratios from 0.12 to 0.14, indicating that they are highly carbonized. The average value oxygen/carbon ratios of bamboo was 0.96, which indicates there is a higher hydrophobicity in its surface. The average oxygen value of bamboo species was 44.04%, bottom than that found for wood (47.42%); the high content of oxygen leads to a higher reactivity, wherein fast biomass volatilization occurs during the thermal degradation process. The presence of oxygen decreases the energy density as well as the miscibility in hydrocarbon fuels. The highest average values ​of extractives were found for bamboo, while the other groups of species showed similar values. The highest ash content occurred in the group of species of alternative materials, bamboo also presented high values according to specific standards.

In this work, coconut waste was evaluated for its potential for biofuel production via pyrolysis by considering physicochemical properties, kinetics of thermal degradation, and chemical composition of products generated. The kinetic of pyrolysis was investigated based on data obtained in a thermogravimetric analyzer at various heating rates. The independent parallel reactions model was used to describe the decomposition process. The activation energy (Ea) values estimated for extractives, hemicellulose, cellulose, and lignin were 194.7–197.7, 122.8–128.6, 244.1–250.5, and 53.0–64.0 kJ mol−1, respectively. The composition of the pyrolytic vapors was investigated via Py-GC/MS at different temperatures in an inert helium atmosphere. The results show that products of pyrolysis of the coconut waste can be a source of valuable chemicals, such as phenol, 1-hydroxy-2-propanone, furfural, and acetic acid. The increase of the reaction temperature resulted in the formation of hydrocarbons and in an increase in the number of aldehydes and ketones.

The aim of this research was to optimize technological applications of biomass waste to obtain energy using both the heuristic and the evolutionary methods. Six steps for the generation of energy were studied with the option of energy integration in the drying and chemical reaction sub-systems. The waste used was the husks of Robusta coffee beans resulting from two distinct treatments, the wet and dry ones. The structural synthesis characterized by branch-and-bound trees resulted in 3780 plausible flowsheets to be analyzed for the four waste-to-energy technologies approached. Experimental studies allowed identification of fundamental characteristics to define the embryonic flowsheet to the process. The heuristic rules made it possible to point out pyrolysis as a promising technology regarding the energy conversion of coffee husks. The finding primary flowsheet, no89, become an economic alternative for generation of electric power from coffee husks. Moreover, impacts of neighbor flowsheets on energy conversion were also analyzed and discussed.

Brewer’s spent grain (BSG) is a large-scale agroindustrial waste that could be more efficiently utilized. This waste is composed of lignocellulosic material and so may serve as a good source of biomass for thermochemical conversion. The present study investigated the fluid dynamics behavior of mixtures of sand and BSG in a spouted bed to assess the viability of the thermochemical conversion of this biomass via fast pyrolysis. Fluid dynamics analyses were performed while varying the mass fraction of BSG (6–80%) and the static bed height (6.6–13.4 cm). Empirical equations for predicting the minimum spouting conditions and the mixing index were obtained using a regression technique, and the selected fluid dynamics parameters were employed in the spouted bed pyrolysis. The bio-oil resulting from this process was rich in phenolic compounds, various nitrogenated compounds (representing precursors for pharmaceuticals) and long-chain hydrocarbons. The products obtained from the analytical and spouted bed pyrolysis processes were also compared.

Lignocellulosic biomass is an important source of energy and it has been extensively studied in the production of second generation ethanol. For this purpose, the complex lignocellulosic matrix must be deconstructed by thermal or chemical pretreatment, followed by cellulose depolymerization using cellulolytic enzymes to release simple fermentable sugars. This process still has several techno-economical drawbacks, such as the cost of enzymes. Aiming to reduce the cost of theses enzymes, their production have been studied by solid-state fermentation (SSF) using low-cost agroindustrial residues as carbon source to the microbial growth. In this context, this work aimed at studying the operational conditions (temperature and moisture content) for the production of cellulases from the fungi Penicillium sp., Rhizomucor sp. and Trichoderma koningii INCQS 40331 (CFAM 422), utilizing natural sugarcane bagasse (NSB) and pretreated by acid-alkaline solution (AAB) and hydrogen peroxide (HPB) as substrates. The study was performed by using three-level factorial design (32) with central points. The results showed that the more suitable fungus for cellulases production was the Trichoderma koningii (8.2 IU/g substrate), followed by Penicillum sp (1.7 IU/g substrate). Moreover, the best results were obtained using NSB for all fungi. Statistical analyses showed that the temperature has a greater effect on the production of cellulases by the evaluated fungi.

With the economic and population growth of certain nations, the need for energy sources has increased, and the fact that the world is dependent on fossil fuels is quite worrying, since they have finite and potentially polluting characteristics. These conditions encourage the growing search for renewable and “clean” sources to help supply the world's energy demand. Thus, many studies focus on the processes of converting agro-industrial waste, a big challenge in the proper destination when considering the huge amount of debris generated. Among these processes, thermochemical conversion through pyrolysis stands out. In order to perform the statistical survey through the bibliometric approach about the pyrolysis of banana residues, this work was built through Scopus and Web of Science databases, focusing on the use of these residues as biomass for energy generation. As a result, the notable growth of studies over the years regarding the use of pyrolysis as a waste conversion process was evidenced. It was concluded that the potential use of banana crop residues as biomass for production of alternative energy sources is highlighted in research conducted in countries that are considered the world's largest fruit producers. Con el crecimiento económico y demográfico de ciertas naciones, la necesidad de fuentes de energía ha aumentado, y el hecho de que el mundo dependa de los combustibles fósiles es bastante preocupante, ya que tienen características finitas y potencialmente contaminantes. Estas condiciones fomentan la búsqueda creciente de fuentes renovables y "limpias" para ayudar a abastecer la demanda mundial de energía. Por lo tanto, muchos estudios se centran en los procesos de conversión de residuos agroindustriales, un gran desafío en el destino adecuado cuando se considera la gran cantidad de escombros generados. Entre estos procesos, se destaca la conversión termoquímica a través del pirólisis. Para realizar la encuesta estadística a través del enfoque bibliométrico sobre el pirólisis de residuos de banano, este trabajo fue construido utilizando las bases de datos Scopus y Web of Science, centrándose en el uso de estos residuos como biomasa para la generación de energía. Como resultado, se evidenció el notable crecimiento de los estudios a lo largo de los años sobre el uso del pirólisis como proceso de conversión de desechos. Se concluyó que el uso potencial de los residuos de cultivos de banano como biomasa para la producción de fuentes alternativas de energía se destaca en una investigación realizada en países que se consideran los mayores productores de frutas del mundo. Com o crescimento econômico e populacional de certas nações, a necessidade de utilização de fontes energéticas tem aumentado, e o fato do mundo ser dependente dos combustíveis fósseis é bastante preocupante, uma vez que estes possuem características finitas e potencialmente poluidoras. Essas condições incentivam a crescente busca por fontes renováveis e “limpas” para auxiliar no suprimento da demanda energética mundial. Assim, muitos estudos voltam-se para os processos de conversão dos resíduos agroindustriais, grande desafio no destino adequado quando se considera a enorme quantidade de detritos gerados. Dentre esses processos, destaca-se a conversão termoquímica, principalmente a pirólise. Com o intuito de realizar o levantamento estatístico por meio da abordagem bibliométrica acerca da pirólise dos resíduos da bananicultura, este trabalho foi construído por meio das bases de dados Scopus e Web of Science, focando na utilização desses resíduos como biomassa para geração energética. Como resultado, foi evidenciado o notório crescimento dos estudos, ao longo dos anos, no que se refere ao uso da pirólise como processo de conversão de resíduos. Concluiu-se que a potencial utilização dos resíduos da cultura da banana como biomassa para produção de fontes alternativas de energia é destaque em pesquisas desenvolvidas nos países que são considerados os maiores produtores mundiais da fruta.

The non-process-elements (NPE's) in the pulp and paper production, in particular chloride (Cl−) and potassium (K+), eventually accumulate in a sodium sulfate recovery cycle of a paper plant, especially on boiler fly ashes (flue gas cleaning). This accumulation often leads to fouling and corrosion. Thus, in order to reduce such problems, a leaching unit is typically integrated aiming to remove Cl− and K+ and recover sodium sulfate (Na2SO4) from boiler fly ashes. In this context, this research is focused on investigating the effects of temperature, ash concentration and pH on the separation efficiency (Cl− and K+ removal and Na2SO4 recovery) of recovery boiler fly ashes using design of experiments in a devised laboratory setup. As expected from the literature, the results obtained reveals that concentration has the most significant effect on the response variables followed by temperature; whereas pH, not mentioned in this application so far, also has a significant effect. The optimum operating condition, which yields 84 wt% of Na2SO4 recovery and 97 wt% of Cl− and K+ removal, is achieved at 60 °C, 50 wt% of ash and pH 9.0. For practical applications, this optimal condition reduces the accumulation of NPE‘s and mitigates the risks of fouling and corrosion.

In this study, the physicochemical properties, the thermal degradation behavior and the products generated from pyrolysis of brewer's spent grain (BSG) were investigated to evaluate the potential of this agro-industrial residue for bio-oil production via pyrolysis. Thermogravimetric analyses were performed in a nitrogen atmosphere. The kinetic parameters were estimated by isoconversional methods and by independent parallel reactions model (IPR). The results showed that the BSG has a good potential for bio-oil production owing to its high volatile matter content and the high heating value. The kinetic behavior was successfully modeled by the IPR model. High added-value compounds were identified from analytical pyrolysis, which indicates that BSG can be a source of important raw materials for the chemical industry.

The fuel derived from algae is a promising alternative that has been studied for supplying the global demand for fuels. The highly proteinaceous microalgae Chlamydomonas reinhardtii has some attributes that can make it an interesting organism for large-scale biomass generation such as: high growth rates, homogeneous biochemical characteristics, robustness and high adaptability, and it can grow both in the light and dark. Thus, in this work the Chlamydomonas reinhardtii was characterized using several techniques, to analyze its potential as feedstock in fuel and chemical production. Analytical pyrolysis was performed with and without catalysts. The tests were performed at 450 °C, 550 °C, 650 °C, and 750 °C in a Pyroprobe CDS 5200. For the catalytic tests a ratio of 1:2 (catalyst:biomass) was used. Non-catalytic pyrolysis indicated that the increase in the temperature increased the amount of hydrocarbon compounds and decreased oxygenated compounds. The bio-oil produced from catalytic pyrolysis showed a decrease in the nitrogenated compounds, which indicate that the addition of a hydrotalcite catalyst that can improve the bio-oil composition.

O crescimento econômico desafia a seguridade da matriz energética em suprir a demanda por energia da sociedade. Além dos riscos ambientais, os combustíveis fósseis estão cada vez menos capazes de suprir esta demanda, fazendo com que pesquisas por fontes renováveis sejam alavancadas. Dentro deste contexto, os recentes estudos sobre a co-pirólise, técnica que promove a diminuição do volume de resíduos e geração de compostos de alto valor agregado, estão ganhando notoriedade. Tendo como objetivo a avaliação da maturidade destes estudos e a formação de um banco de dados específico sobre o tema, utilizou-se como ferramenta a revisão bibliométrica, esta que permite a seleção de artigos dentro de um banco de dados a partir de parâmetros estatísticos, como número de citações e fator de impacto. Portanto, pode-se concluir que apesar de recente, a co-pirólise se apresenta como uma técnica promissora, simples e de baixo custo, para o melhoramento do rendimento e composição estrutural dos produtos de pirólise.

Several routes of reusing carton packaging waste have been proposed along the years. Pyrolysis of carton waste has been highlighted due to obtain high value-added products such as paraphinic oils and aluminum. Recently, the spouted bed has been investigated as a promising reactor for pyrolysis of solids. By suitably setting up pyrolysis, a fully investigative procedure of three phase (air-LDPE/Al-sand) flow dynamics in the conical spouted bed is needed. Thus, this research aims at analyzing the fluid dynamics behavior of conical spouted beds comprised mixtures of sand and LDPE/Al composite. Eulerian-granular multiphase model for describing the air-particle mixture flow in a conical spouted bed is used. By using the computational fluid dynamics and bi-dimensional structured grid, the solution of model equations is obtained. In addition, the following models are tested: laminar, mixture k-e, per phase k-e and disperse k-e models. Based on data analyses, it can be identified that disperse k-e model describes better air-particles flow in conical spouted beds comprised sand and LDPE/Al composites mixtures. The results show that bed pressure drop and fountain height are in agreement with those predicted by disperse k-e model.

Brewer's spent grain (BSG) is the main by-product of the brewing industry. In this work, the pyrolysis of BSG using a fixed bed reactor was studied with respect to the valorization of this residue. The effects of the heating rate (10-50 °C/min) and temperature (450-650 °C) on the yields of pyrolysis products and on the physicochemical properties of the main products were quantified. The highest liquid yield (60.7%) was obtained at the pyrolysis temperature of 650 °C with a heating rate of 30 °C/min. The highest char yield (29.3%) was obtained at 550 °C and at heating rate of 10 °C/min. The results showed that high heating rates suppress dehydration reactions and favor bio-oil production. The produced biochar showed good potential for fuel application due to its high heating value (HHV) (27.1–28.3 kJ/g), moderate ash content (11.5%) and low sulfur content (

The singularity of air-particle flow characteristics and segregation phenomenon are still the main obstacles for application of conical spouted bed (CSB) for fast pyrolysis. This paper aims to investigate statistically the operating parameters (minimum spouting velocity and bed pressure drop) and biomass segregation (biomass mixing index) in a CSB composed of biomass (coconut and cocoa shells) and sand mixtures. Models for the pressure drop and inlet air velocity at the minimum spouting condition and for the axial mixing index were obtained. The bed voidage does not change significantly with the increase of biomass mass fraction (coconut and cocoa shells), therefore, larger amounts of biomass can be used without greatly increasing or decreasing the inlet air velocity to stabilize the spouted regime. From the analysis of bed stability and particle segregation, significant insights were obtained for future application of the CSB for the pyrolysis of biomasses. It is recommended the use of mixtures with 40 wt% of coconut shells and 75 wt% of cocoa shells in initial pyrolysis tests in CSB reactor. The cocoa shells particles are more suitable to pyrolysis because of their higher flowability.

Com o crescimento econômico e populacional de certas nações, a necessidade de utilização de fontes energéticas tem aumentado, e o fato do mundo ser dependente dos combustíveis fósseis é bastante preocupante, uma vez que estes possuem características finitas e potencialmente poluidoras. Essas condições incentivam a crescente busca por fontes renováveis e “limpas” para auxiliar no suprimento da demanda energética mundial. Assim, muitos estudos voltam-se para os processos de conversão dos resíduos agroindustriais, grande desafio no destino adequado quando se considera a enorme quantidade de detritos gerados. Dentre esses processos, destaca-se a conversão termoquímica, principalmente a pirólise. Com o intuito de realizar o levantamento estatístico por meio da abordagem bibliométrica acerca da pirólise dos resíduos da bananicultura, este trabalho foi construído por meio das bases de dados Scopus e Web of Science, focando na utilização desses resíduos como biomassa para geração energética. Como resultado, foi evidenciado o notório crescimento dos estudos, ao longo dos anos, no que se refere ao uso da pirólise como processo de conversão de resíduos. Concluiu-se que a potencial utilização dos resíduos da cultura da banana como biomassa para produção de fontes alternativas de energia é destaque em pesquisas desenvolvidas nos países que são considerados os maiores produtores mundiais da fruta.

The use of agricultural residues as a bioenergy source has aroused increasing interest in the bioenergy sector. This paper discusses the exploitation of cocoa and coffee husks using anaerobic digestion, pyrolysis and direct combustion technologies. The structural synthesis method that was used to obtain electricity was performed using a State Tree. Structural elements were combined to form branches for each chemical route. Structural optimisation was conducted using the heuristic method. The promising technological routes included the anaerobic digestion of cocoa husks in a batch reactor and the pyrolysis of coffee husks preceded by pelletisation. The systematic representation of the problem using the process engineering approach was a promising method for evaluating the process of obtaining energy from fruit wastes.

The independent parallel reaction model (IPR model) is applied in this work to study the slow dynamic pyrolysis of sugarcane bagasse, based on a thermogravimetric analysis of three ranges of particle diameters. The kinetic parameters and mass fraction of each principal pseudo-component of biomass (hemicellulose, cellulose and lignin) are estimated using the Differential Evolution Algorithm. A comparison of the estimated mass fractions and Arrhenius parameters against experimental values reported in the literature shows good agreement. The influence of various kinetic parameters of the model is also analyzed by means of sensitivity studies using derivative methods based on the DASPK 3.0 code. The results of the relative parametric sensitivity indicate that activation energies affect bagasse conversion more strongly than other parameters, followed by the pre-exponential factors of Arrhenius equation and mass fractions. The sensitivity of the IPR kinetic model to the orders of reaction is very slight.

Many processes have been used for recycling of carton packaging wastes. The pyrolysis highlights as a promising technology to be used for recovering the aluminum from polyethylene and generating products with high heating value. In this paper, a study on pyrolysis reactions of carton packaging wastes and its pure components was performed in order to estimate the kinetic parameters of these reactions. For this, dynamic thermogravimetric analyses were carried out and two different kinds of kinetic models were used: the isoconversional and Independent Parallel Reactions. Isoconversional models allowed to calculate the overall activation energy of the pyrolysis reaction, in according to their conversions. The IPR model, in turn, allowed the calculation of kinetic parameters of each one of the carton packaging and paperboard subcomponents. The carton packaging pyrolysis follows three separated stages of devolatilization. The first step is moisture loss. The second stage is perfectly correlated to devolatilization of cardboard. The third step is correlated to devolatilization of polyethylene.

This paper presents a kinetic study of pyrolysis of sugarcane bagasse from dynamic thermogravimetric experiments (TG). The methods of Kissinger, Ozawa, Starink, Kissinger-Akahira-Sunose and Friedman were used to estimate the activation energy. These methods consider the temperature shifts with increase of heating rate for a given conversion in dynamic TG tests. The activation energy values obtained by the isoconversional methods were in a range 182.8 192.4 kJ·mol-1, values very close to the other biomasses presented by literature.

Currently, the generation of modern solid waste has caused large environmental impact. Because of the high addedvalue components, the carton packaging highlights among the wastes generated in large urban areas. The manufacture of tiles (or plates) and the pyrolysis are the main routes for the recycling of these wastes. In literature, the conical spouted bed has been pointed out as a promising air-solid contact system for processing the pyrolysis. Thus, this research aims to analyze the air-carton packaging waste flow dynamics in a conical spouted bed. The flow behavior of air-waste was experimentally investigated by analyzing data of bed pressure drop, air velocity and fountain height. Moreover, the simulation of operating conditions in the conical spouted bed was conducted using the computational fluid dynamics (CFD). It was found that particles of carton packaging in a shaped of disks do not achieve the spouting regime. However, for beds with mixtures composed of polyethylene and carton disks(5 and 10% carton weight), the spouting regimes wereattained.Furthermore, the simulations in ANSYS FLUENT software using the Eulerian Granular Multiphase model showed good agreement with experimental data.

Thermogravimetric analysis was made of slow sugarcane bagasse pyrolysis. Several models of primary decomposition were tested and compared. Kinetic parameters were estimated using nonlinear regression and the differential evolution method. A one-step reaction model with first-order and n-order kinetics, a consecutive reaction model, and an independent parallel reaction model were employed in the modeling. The results show that the one-step model does not accurately represent the data of weight loss (TG) and its derivative (DTG). The consecutive reaction model yielded the expected activation energy results for the first two peaks corresponding to hemicellulose and cellulose, but inaccurate results for lignin. The independent parallel reaction model yielded the best results for the three subcomponents. The mass fraction of each subcomponent was estimated by the three independent parallel reaction models, showing values consistent with those reported in the literature.

The pyrolysis kinetics of sugarcane bagasse in nitrogen flow was studied by thermogravimetric analysis from room temperature to 1173 K at different heating rates (1.5, 3, 5, 10, 15, 20, 30 and 50 K/min). As there are three distinct devolatilization peaks in the DTG curve, each peak was associated to thermal decomposition of an individual biomass subcomponent (hemicellulose, cellulose and lignin). The kinetic model adopted was a consecutive reactions model. The kinetic parameters of the pyrolysis process, such as activation energy and pre-exponential factor, were calculated by least squares non-linear method and Scilab are used as the simulation tool. The simulated results showed a good agreement with the experimental data and the parameters found are similar to reported by the literature.

The majority of the pyrolysis kinetics models presented in the literature is nonlinear. In these models, the influence of temperature is normally described by the Arrhenius equation. In some studies related to parameter estimation of nonlinear models suggestions can be found for reparameterization of the Arrhenius-type equation due to inadequate results on the parameter estimation. In this work, kinetic modeling is proposed in order to predict the primary biomass decomposition behavior under a dynamic regime. This model is based on the traditional model of parallel reactions and uses the Arrhenius-type equation in the reparameterized form. Some nonlinearity measures are used as a tool to correctly estimate the kinetic parameters of the pyrolysis of sugarcane bagasse. The predictions from the proposed model properly reproduced the experimental DTG curves. The reparametrized model showed non-significance for bias and nonlinearity measures.

Modelling of heat and mass transfer in moving bed dryers is generally based on the application of mass and energy balance equations for both solid and fluid phases (two-phase model). Some classical hypotheses are assumed in the development of these equations, such as flat air velocity profiles and constant physicochemical parameters. The main goal of this work was to ascertain the validity of this assumption applied to the modelling of concurrently moving bed dryers. Comparisons of the experimental data and the simulated responses revealed the significant influence of the distribution of air velocity in the drying process. The influence of various physicochemical parameters of the model was also analyzed based on sensitivity studies using experimental design and derivative methods based on the DASPK 3.0 code.

Heat and mass transfer in moving bed dryers is usually modelled based on the application of mass and energy balance equations for both solid and fluid phases (two-phase model). The development of these equations is based on the assumption of classical hypotheses, including flat air velocity profiles. The main goal of this work was to ascertain the validity of this hypothesis by means of an experimental and simulation study of a countercurrent moving bed, using soybean seeds as particles. The radial air profile was taken into account by means of a suitable empirical correlation and a mechanistic model validated by experimental results. Comparisons of the experimental data and the simulated responses indicated that the hypothesis of flat air velocity profiles limits the precision of the results obtained by the model.

RESUMO – A cultura da macadâmia esta em pleno desenvolvimento no Brasil, sendo o estado do Espirito Santo o segundo maior produtor nacional. A utilizacao do seu c arpelo para geracao de energia renovavel torna-se uma alternativa muito atrativa, visto o facil acesso e obtencao deste residuo do processo de beneficiamento da macadâmia. A secagem do carpelo aumenta o seu poder calorifico. O leito de jorro vem sendo utilizado para o processo de secagem devido as suas vantagens, como proporcionar um maior contato gassolido e um alto coeficiente convectivo de calor e de transferencia de massa entre as fases. Neste trabalho, objetivou-se estudar a secagem do carpelo da macadâmia em leito de jorro, avaliando quais as melhores condicoes operacionais: temperatura e vazao do ar. Sendo esta ultima uma funcao da velocidade minima de jorro, determinada atraves da construcao da curva caracteristica. A queda de pressao maxima tambem foi determinada. O menor teor de umidade obtido ao final dos experimentos foi de aproximadamente 1,5%. As equacoes que melhor representaram a cinetica de secagem do carpelo foram a equacao de Page e a equacao de Overhults.

This study analyzed the influence of the following parameters: overall volumetric heat transfer coefficient, coefficient of heat loss, drying rate, specific heat of the solid and specific heat of dry air on the prediction of a model for the fertilizer drying in rotary dryers. The method of parametric sensitivity using an experimental design was employed in this study. All parameters studied significantly affected the responses of the drying model. In general, the model showed greater sensitivity to the parameters drying rate and overall volumetric heat transfer coefficient.

As reported in the literature, the post-consumption carton packaging has been recycled using different process. Pyrolysis can be a promising technology to be used for recovering the aluminum from polyethylene and generating products with high heating value. In this research paper, by using thermogravimetric analysis (TGA), a kinetic study on pyrolysis reactions was performed. Furthermore, the activation energy of pyrolysis reaction was estimated using the methodology proposed by Ozawa (1965).

Particulate air pollution is associated with a range of effects on human health, including effects on the respiratory and cardiovascular systems, asthma and mortality. Hence, the development of an efficient forecasting and early warning system for providing air quality information towards the citizen becomes an obvious and imperative need. The objective of this work was to investigate that forecasting capability using linear models (such as ARX, ARMAX, output-error and Box-Jenkins), and neural networks. They were used meteorological variables and 24-h PM 10 concentration of the present day as input data. As output foreseen by the models, the 24-h PM 10 concentration is obtained, with horizon of prediction of up to three days ahead. The results showed that fairly good estimates can be achieved by all of the models, but Box-Jenkins model showed best fit and predictability.

The aim of this work was to analyze the heat and mass transfer between the air and soybean seeds in a concurrent moving bed dryer with an air profile that is not flat. The modelling of heat and mass transfer in moving bed dryers is generally based on the application of mass and energy balance equations for both solid and fluid phases (two-phase model). In the establishment of these equations some classical hypotheses such as that the fluid velocity profile is flat, are assumed. The main goal of this work was to verify the validity of this assumption by means of an experimental and simulation study in a concurrent moving bed, using soybean seeds as particles. In this work, the radial air profile was taken into account by means of a suitable empirical correlation and a mechanistic model validated by experimental results. The numerical solution of the one-dimension boundary value problem was obtained by means of a computational code based on axial integration through the DASSL code. By comparison of the experimental data and the simulated responses for air temperature and seed moisture content, it was possible to verify the significant effect of air velocity distribution.

Particulate air pollution causes a wide range of effects on human health, including disorders of the respiratory and cardiovascular systems, asthma and can cause mortality. Hence, the development of an efficient air quality forecasting and early warning system is an obvious and imperative need. The objective of this work was to investigate this forecasting possibility using linear models (such as ARX, ARMAX, output–error and Box–Jenkins), and Neural Networks (NNs). The input data for the models were meteorological variables and the 24–h average PM10 concentration of the present day, while the output was the 24–h average PM10 concentration predicted for a 3–day horizon. The results revealed that all the models yield fairly good estimates, but the Box–Jenkins model showed the best fit and predictability.

The post-consumption carton packaging has been recycled using different process. Pyrolysis can be a promising technology to be used for recovering the aluminum from polyethylene and generating products with high heating value. In this research paper, a kinetic study on pyrolysis reactions was performed in order to estimate the global activation energy using methods of Starink, Kissinger and Kissinger-Akahira-Sunose. Therefore, for both samples of carton packaging and its pure components, dynamic thermogravimetric analyses (TGA) were carried out. The results show that Starink, Kissinger and Kissinger-Akahira-Sunose methods applied to carton packaging, cardboard and polyethylene can be satisfactorily used for estimating the global activation energy and showed similar results between each other.

The macadamia tree is known for producing fruit high in fats, enclosed in very hard woody shells. Macadamia nut shell, considered as a by-product from macadamia nut processing, may be a suitable option for pyrolysis. These residues are constituted of cellulose, hemicellulose, lignin and extractives. The Independent Parallel Reaction (IPR) Model has been applied in this work to study the pyrolysis of macadamia nut shell from thermogravimetric experiments. The kinetic parameters and mass fraction of each component were estimated using the Differential Evolution Algorithm. The influence of the model parameters was also analyzed by means of sensitivity studies. The results showed that the decomposition of the macadamia nut shell is more sensitive to the parameters related to the decomposition of lignin. The results of sensitivity analysis also showed that the activation energy affects the total biomass conversion more strongly than the other parameters and the contribution of extractives in the IPR model is as important as the hemicellulose.