Engenharia Agrícola
URI permanente desta comunidadehttps://locus.ufv.br/handle/123456789/11733
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Item Assessing the potential of renewable energy sources (biogas and sludge) in a full-scale UASB-based treatment plant(Renewable Energy, 2018-08) Rosa, A.P.; Chernicharo, C.A.L.; Lobato, L.C.S.; Silva, R.V.; Padilha, R.F.; Borges, J.M.This study aimed at evaluating the energy potential of the by-products (sludge and biogas) produced in full-scale UASB-based sewage treatment plant (STP). The work was developed at the Laboreaux STP (Population = 70,000 inhabitants), located in the city of Itabira, in the state of Minas Gerais – Brazil. To determine the biogas energy potential, the volumetric production and its composition were monitored. The dehydrated sludge from filter press was characterized according to immediate composition, elemental composition, lower calorific value (LCV) and higher calorific value (HCV). Overall, the gross energy potentials of the biogas and sludge produced in the STP were 7518 MJ d^−1 and 10,962 MJ d^−1, respectively. Considering the use of biogas to produce electricity (efficiency of 30%), it could be possible to supply 57.6% of energy demand of STP. With a thermal treatment of sludge from filter press, with or without energy recovery, it would have a reduction of mass disposal in the landfill in the order of 46.0% that represents a benefit in the sludge management.Item Biodiesel policy for family farms in Brazil: one-size-fits-all?(Environmental Science & Policy, 2013-03) Leite, Joã o Guilherme Dal Belo; Bijman, Jos; Giller, Ken; Slingerland, MajaDriven by the increasing environmental concern related to the use of fossil fuels and the growing worldwide demand for biofuels, the Brazilian government launched a national biodiesel policy promoting feedstock supply from family farms. Especially in semi-arid regions farmers have been encouraged to grow castor bean. However, there has been little farmer uptake and knowledge is lacking regarding the main constraints that hamper farmers’ engagement in the biodiesel market. A farm typology, developed on the basis of original data gathered in two municipalities in the Southeast region of Brazil, revealed that the majority of farmers (livestock, mixed and less endowed farm types) face great challenges to participate in biodiesel markets. A stronger policy impact could be achieved by the promotion of biodiesel crops that have alternative markets and fit more easily into the current farming system, such as sunflower, resulting in reduced trade-offs with current crop activities and allowing synergies between fuel and feed production (livestock farmers). Better enforcement of resource providing contracts are critical to avoid default and to alleviate labour (mixed farmers) and land constraints (less endowed farmers), thereby improving farmers’ ability to engage in biodiesel crop production. Furthermore, soybean farmers lack policy instruments based on price incentives which could enable their engagement in sunflower production.Item Bioethanol production potential from brazilian biodiesel co-products(v. 35, n. 1, p. 489- 494, jan. 2011, 2011-01) Visser, Evan Michael; Oliveira Filho, Delly; Martins, Marcio Arêdes; Steward, Brian L.One major problem facing the commercial production of cellulosic ethanol is the challenge of economically harvesting and transporting sufficient amounts of biomass as a feedstock at biorefinery plant scales. Oil extraction for biodiesel production, however, yields large quantities of biomass co-products rich in cellulose, sugar and starch, which in many cases may be sufficient to produce enough ethanol to meet the alcohol demands of the transesterification process. Soybean, castor bean, Jatropha curcas, palm kernel, sunflower and cottonseed were studied to determine ethanol production potential from cellulose found in the oil extraction co-products and also their capacity to meet transesterification alcohol demands. All crops studied were capable of producing enough ethanol for biodiesel production and, in the case of cottonseed, 470% of the transesterification demand could be met with cellulosic ethanol production from oil extraction co-products. Based on Brazilian yields of the crops studied, palm biomass has the highest potential ethanol yield of 108 m^3 km^−2 followed by J. curcas with 40 m^3 km^−2. A total of 3.5 hm^3 could be produced from Brazilian soybean oil extraction co-products.Item Biogas production from thermophilic anaerobic digestion of kraft pulp mill sludge(Renewable Energy, 2018-08) Lopes, Alice do Carmo Precci; Silva, Cláudio Mudadu; Rosa, André Pereira; Rodrigues, Fábiode ÁvilaPrimary and secondary sludges originating from kraft pulp mill effluent treatment plants represent an environmental challenge. Their final disposal mainly includes landfill or burning in the mill's biomass boiler. Seeking energy self-sufficiency and better environmental outcomes, the pulp industry is looking to develop new waste management strategies. Biogas production is a millennial technology already applied in many fields, but still behind in terms of pulp and paper mill sludges. Due to the high moisture content of sludge, anaerobic digestion shows great potential. This paper aimed to study biogas pro- duction using kraft pulp mill primary and secondary sludges under thermophilic conditions, coupling laboratory experiments with mathematical modeling. Methane production was estimated through the Biochemical Methane Potential (BMP). The Process Simulation Model developed by Rajendran et al. [1] was calibrated for kraft pulp mill sludge based on the BMP results. Cumulative methane production from the secondary sludge reached 46.9 NmL CH 4 /g VS in 30 days. In addition, the Rajendran et al. [1] model was shown to be suitable for simulating the methane yield from bleached kraft pulp mill secondary sludge after minor adjustments. The energy balance showed that the anaerobic digestion process under thermophilic condition for kraft pulp mill secondary sludge still is not feasible on large scale, since the heat produced by biogas was smaller than the heat demanded for heating the reactors.Item Changes in land use and land cover as a result of the failure of a mining tailings dam in Mariana, MG, Brazil(Land Use Policy, 2018-01) Aires, Uilson Ricardo Venâncio; Santos, Bismarck Soares Matos; Coelho, Clívia Dias; Silva, Demetrius David da; Calijuri, Maria LúciaThe failure of the mining tailings dam in Mariana, Minas Gerais, Brazil, was the largest disaster of its type in Brazil, generating serious environmental and socioeconomic problems. The aim of this study was to identify potential sites for the disposal of the tailings that accumulated along the watercourses affected by the dam failure in the municipalities of Mariana and Barra Longa, as well as to quantify the area affected by the tailings. To quantify the area affected by the tailings dam failure, the Land Change Modeler (LCM) tool was used to verify the changes in land use and land cover that occurred in the periods before and after the environmental impact. For the identification of the suitable sites for tailings disposal, multicriteria analysis was performed using the Idrisi Selva® software and considering three scenarios to identify potentially affected areas through the application of the weighted linear combination (WLC) and ordered weighted average (OWA) techniques. In scenario 1, the WLC technique was applied, considering average risk and high compensation. In scenarios 2 and 3, the OWA technique was applied, with high risk and high compensation for scenario 2 and low risk and high compensation for scenario 3. The highest suitability value for tailings disposal was identified in scenario 2, which obtained the maximum value of 213 on a scale of 0–255, while for the scenarios 1 and 3, the suitability values were 158 and 124, respectively. The largest site for the tailings dam identified in the analysis for the municipally of Mariana has a size of 0.25 km2 and obtained a suitability value of 207. In the municipally of Barra Longa, the largest site identified has a size of 0.037 km2, with maximum suitability value of 209. In relation to the changes in land use and cover, it was verified that the vegetated areas, composed mainly of riparian forest and pasture, presented greater losses as a consequence of the dam failure, with reductions of 11.99 and 4.81 km2, respectively, demonstrating that the dam rupture disaster has caused serious damage to the environment and the population living in the region.Item Characterization and mapping of waste from Coffee and Eucalyptus production in Brazil for thermochemical conversion of energy via gasification(Renewable and Sustainable Energy Reviewspt-BR, 2013-05) Silva, Jadir Nogueira da; Oliveira, Jofran Luiz de; Pereira, Emanuele Graciosa; Oliveira Filho, Delly; Carvalho, Daniel RizzoThe generation of waste is an intrinsic characteristic of forestry and agricultural production and has become a major concern. Brazil is a great agricultural producer, and in recent years both the planted area and crop production have grown significantly, with a corresponding increase in agricultural waste. In the context of climate change, efficiency and energy security, it is fundamental to develop alternative energies that meet the needs of both the energy supply and sustainable development. Wood chips and coffee husks are low cost residues and potentially capable of generating heat, steam and electric power, thus they can serve as an alternative fuel for generating energy. This work aims to relate the agricultural market to the energy market, using waste from coffee and eucalyptus production to generate energy, as well as mapping waste production in Brazil by region. It was observed that Brazil has a great capacity to generate alternative energy, since approximately 11.4×10^6 t of wastes are generated per year from coffee and eucalyptus production alone. These wastes can be used for the thermochemical conversion of energy via gasification, with potential to generate a total of 201.3 PJ.Item Climate change and electricity demand in Brazil: a stochastic approach(Energy, 2016-05-01) Trotter, Ian M.; Bolkesjø, Torjus Folsland; Féres, José Gustavo; Hollanda, LaviniaWe present a framework for incorporating weather uncertainty into electricity demand forecasting when weather patterns cannot be assumed to be stable, such as in climate change scenarios. This is done by first calibrating an econometric model for electricity demand on historical data, and subsequently applying the model to a large number of simulated weather paths, together with projections for the remaining determinants. Simulated weather paths are generated based on output from a global circulation model, using a method that preserves the trend and annual seasonality of the first and second moments, as well as the spatial and serial correlations. The application of the framework is demonstrated by creating long-term, probabilistic electricity demand forecasts for Brazil for the period 2016e2100 that incorporates weather uncertainty for three climate change scenarios. All three scenarios indicate steady growth in annual average electricity demand until reaching a peak of approximately 1071e1200 TWh in 2060, then subsequently a decline, largely reflecting the trajectory of the population projections. The weather uncertainty in all scenarios is significant, with up to 400 TWh separating the 10th and the 90th percentiles, or approximately ±17% relative to the mean.Item Comparison of the water footprint of two hydropower plants in the Tocantins River Basin of Brazil(Journal of Cleaner Production, 2017-06-01) Coelho, Clívia Dias; Silva, Demetrius David da; Sediyama, Gilberto Chohaku; Moreira, Michel Castro; Pereira, Silvio Bueno; Lana, Ângela maria QuintãoThe purpose of this study was to characterize the water footprint of the Tucuruí and Lajeado hydropower plants (HPPs), located in the Tocantins River Basin, Brazil. The water footprint of hydropower was evaluated by three different methods based on the electricity production of the HPP and the monthly and annual evaporation rates estimated according to Penman's method. The first water footprint method (WF-1) considers only the gross water consumption by the HPPs; the second method (WF-2) considers the net water consumption, discounting what would be lost by evapotranspiration in the area previous to the construction of the reservoir; and the third method (WF-3) accounts for the net water balance. The results demonstrated that the estimates of average annual water footprint for the Tucuruí reservoir, using the WF-1, WF-2 and WF-3 methods, were, respectively, 49 m 3 /GJ, 26 m 3 /GJ and 21 m 3 /GJ, while for Lajeado, these estimates were 95 m 3 /GJ, 48 m 3 /GJ and 21 m 3 /GJ. The flooded area of the reservoir per unit of installed capacity of Tucuruí HPP is 34 ha/MW, while for Lajeado, this value reaches 70 ha/MW, which explains Tucuruí's greater water efficiency. Confirming this result, the normalized WFs based on the reservoir area and the installed capacity were approximately 100% higher for the Lajeado HPP than for the Tucuruí HPP through all water footprint methods analyzed. The WF-2 method is the most appropriate to account for the consumption of water directly related to hydroelectric energy generation since it considers the change in evaporation caused by the construction of the reservoir.Item Degradation kinetics of pirimiphos-methyl residues in maize grains exposed to ozone gas(Elsevier Journal of Stored Products Research, 2017-12) Freitas, Romenique da Silva de; Faroni, Lêda Rita D'Antonino; Queiroz, Maria Eliana Lopes Ribeiro de; Heleno, Fernanda Fernandes; Prates, Lucas Henrique FigueiredoThis work investigates the kinetics of degradation of pirimiphos-methyl residues in maize grains exposed to ozone gas and evaluates the effect of ozonation on grain quality. The assays employed maize grains treated with the insecticide, namely Actellic 500 CE® (pirimiphos-methyl), which were exposed for different periods to ozone gas at a concentration of 0.86 mg L−1, provided at a continuous flow rate of 1.0 L min−1. The insecticide residues were extracted from the grains using solid-liquid extraction with low temperature partitioning. The extracts were analyzed by gas chromatography with electron capture detection. Ozone effectively degraded more than 91% of the pirimiphos-methyl residues, with the degradation efficiency increasing in direct proportion to the duration of exposure to the gas. A first order kinetic model provided the best fit to the degradation data. The use of ozone gas did not alter the qualitative characteristics of the maize.Item Effect of influent aeration on removal of organic matter from coffee processing wastewater in constructed wetlands(Journal of Environmental Management, 2013-10-15) Rossmann, Maike; Matos, Antonio Teixeira; Abreu, Edgar Carneiro; Silva, Fabyano Fonseca; Borges, Alisson Carrarohe aim of the present study was to evaluate the influence of aeration and vegetation on the removal of organic matter in coffee processing wastewater (CPW) treated in 4 constructed wetlands (CWs), characterized as follows: (i) ryegrass (Lolium multiflorum) cultivated system operating with an aerated influent; (ii) non-cultivated system operating with an aerated influent, (iii) ryegrass cultivated system operating with a non-aerated influent; and (iv) non-cultivated system operating with a non-aerated influent. The lowest average chemical oxygen demand (COD), biochemical oxygen demand (BOD) and total suspended solids (TSS) removal efficiencies of 87, 84 and 73%, respectively, were obtained in the ryegrass cultivated system operating with a non-aerated influent. However, ryegrass cultivation did not influence the removal efficiency of organic matter. Artificial aeration of the CPW, prior to its injection in the CW, did not improve the removal efficiencies of organic matter. On other hand it did contribute to increase the instantaneous rate at which the maximum COD removal efficiency was reached. Although aeration did not result in greater organic matter removal efficiencies, it is important to consider the benefits of aeration on the removal of the other compounds.Item Energy balance in the production of mountain coffee(Renewable and Sustainable Energy Reviews, 2014-11) Lacerda Filho, Adílio Flauzino de; Palacin, Juan José Fonseca; Rigueira, Roberta Jimenez de Almeida; Ribeiro, Aristides; Melo, Evandro de CastroCoffee culture is highly relevant in Brazilian agriculture in socioeconomic terms. The energy balance of production systems results from the subtraction of the consumed energy (MJ ha-1) from the produced energy (MJ ha-1), in any culture or system. Produced energy is understood as the transformation resulting from the production of grains or fruits, or dry matter, into energy. Consumed energy or cultural energy (MJ ha-1) is understood as the sum of the energy coefficients related to the fertilizers, seeds, fungicides, herbicides, insecticides, incident solar energy during the cycle and operations related to sowing, fertilization, application of products and manual harvesting. Post-harvest is considered to be the sum of the energy coefficients spent in the pre-processing and processing operations used in each treatment. The present work aimed at evaluating the energy balance in a mountain coffee production system with emphasis on production, harvest and post-harvest. It was concluded that plants and their individual components take little advantage from the amount of energy aggregated in the energy balance (less than 0.3%).Item Hermetic storage for control of common bean weevil, Acanthoscelides obtectus (Say)(Elsevier Journal of Stored Products Research, 2016-03) Freitas, R. S.; Faroni, L. R. A.; Sousa, A. H.This study evaluated hermetic storage as a method of controlling Acanthoscelides obtectus (Coleoptera: Chrysomelidae: Bruchinae) in stored beans. Recently harvested “vermelhinho” cultivar of the common red bean was used, which had already been infested by A. obtectus in the field. Beans with a moisture content of 15.0% wet basis were stored in silo bags (3 kg), plastic bottles (1.5 L), or non-hermetic glass containers (3 L) (control) for 120 days. The packages were stored in an acclimatized chamber at 25 °C with a relative humidity of 70 ± 5%. At time intervals of 0, 30, 60, 90, and 120 days, three packages of each treatment were opened, and analyses were performed to assess the infestation percentage by insect pests, moisture content, density, electrical conductivity, germination percentage, and cooking time. There was no increase in infestation by A. obtectus in the grains stored in the silo bags and plastic bottles during the 120 days of storage; however, there was a significant increase in infestation in the grains in non-hermetic storage (control). The quality of the beans correlated with infestation; it was not altered in the hermetic storage systems and decreased in the control sample. Hermetic storage of common beans is an effective tool in the control of A. obtectus.Item Poultry litter as biomass energy: A review and future perspectives(Renewable and Sustainable Energy Reviews, 2017-09) Dalólio, Felipe Santos; Silva, Jadir Nogueira da; Oliveira, Angélica Cássia Carneiro de; Tinôco, Ilda de Fátima Ferreira; Barbosa, Rúben Christiam; Resende, Michael de Oliveira; Albino, Luiz Fernando Teixeira; Coelho, Suani TeixeiraPoultry litter is characterized as a heterogeneous compound produced after a poultry production cycle, being the sum of the material used as bedding in association with the animal waste, dead skin, feed scraps, water, feathers and the resulting microbiota. The expansion of poultry production around the world has resulted in elevated generation of this residue. Over the years its use has been restricted to organic fertilizer or simply as a waste to be eliminated and disposed of in the environment. However, this mechanism has caused environmental and social damages due to its indiscriminate use. Because of the energetic and biological properties of poultry litter, its sustainable use as energy can be obtained via thermochemical processes such as anaerobic digestion and through combustion, gasification, pyrolysis or power co-generation systems, in which there is a combination of one or more processes. As a result, there is the potential for generating heat, electricity, fuel gas and biochar with low emission of pollutants. However, it is emphasized that there is no standard with regards to its composition and the source material type, where efforts are more focused on the contents of moisture and inorganic compounds. Therefore, processes that seek to use poultry litter as fuel biomass should be well-controlled and efficient for successful energy generation. In this sense, the objective of this study is to analyze the characteristics of poultry litter as fuel, discuss the main thermochemical processes for its energetic conversion and propose measures to improve its performance as a sustainable biomass.Item Prospects and risks of the use of castor oil as a fuel(Biomass and Bioenergy, 2008-02) Silva, Jadir Nogueira da; Scholz, VolkhardCastor oil is more than just a raw material in great demand by the pharmaceutical and chemical industries. In several southern countries its use as a fuel is also being discussed in connection with social and ecological aspects. A few properties, in particular the extremely high viscosity and high water content, complicate the use of straight castor oil as a fuel for internal combustion engines. A better perspective may be possible by transesterification and the addition of this biodiesel to fossil diesel fuel. This, however, calls for considerably lower castor oil prices than are at present being paid on the world market.Item Resistance to forced airflow through layers of composting organic material(Waste Management, 2014-12-20) Teixeira, Denis Leocádio; Matos, Antonio Teixeira de; Melo, Evandro de CastroThe objective of this study was to adjust equations to estimate the static pressure gradient of airflow through layers of organic residues submitted to two stages of biochemical degradation, and to evaluate the static pressure drop of airflow thought the material layer. Measurements of static pressure drop in the layers of sugarcane bagasse and coffee husks mixed with poultry litter on day 0 and after 30 days of composting were performed using a prototype with specific airflow rates ranging from 0.02 to 0.13 m^3 s^−1 m^−2. Static pressure gradient and specific airflow rate data were properly fit to the Shedd, Hukill & Ives and Ergun models, which may be used to predict the static pressure gradient of air to be blown through the organic residue layers. However, the Shedd model was that which best represented the phenomenon studied. The static pressure drop of airflow increased as a power of the material layer thickness and showed tendency for decreasing with the biochemical degradation time of the organic material.Item Thermal inertia effects of the structural elements in heat losses during the charcoal production in brick kilns(Fuel, 2018-08-15) Bustos-Vanega, Jaime Daniel; Martins, Marcio Arêdes; Carneiro, Angélica de Cassia Oliveira; Freitas, Arthur Gomes; Barbosa, Ruben ChristianBrazil is the largest producer of charcoal from planted forests with 5.5 million tons in 2016. The Brazilian steel industry consumes 85% of the national production of charcoal from eucalyptus. The walls and floor of industrial brick kilns are built using isolation materials that minimize heat losses during the wood carbonization stage. However, the thermal inertia of these components represents additional heat that must be removed during the charcoal cooling stage, as reflected in the extended process time. This study aims to evaluate the effect of the thermal inertia of the kiln structural elements for the charcoal production. A CFD (Computational Fluid Dynamics) analysis was performed to simulate the heating and cooling of the system composed of wood, carbonization gases, brick walls and floor. A typical industrial kiln with capacity of 700 m3 was modeled and validated using a set of experimental measurements of temperatures during a 4-day carbonization stage with final temperature of 400 °C and an 8 day cooling stage. The temperature profile in the walls was linear, corresponding to a pseudo-steady state, where the thermal load increases with the pyrolysis time. The heat transfer at the floor is extensive; therefore, the adiabatic boundary condition cannot be imposed at the wood bed–floor interface. Our findings provide important information for the improvements in the kiln operation and allow establishment of consistent initial conditions of temperature and heat flux for kinetics models for charcoal cooling in kilns.