Engenharia AgrícolaArtigos relacionados a Cafeiculturahttp://www.sbicafe.ufv.br/handle/123456789/103632024-03-04T21:51:02Z2024-03-04T21:51:02ZCoffee dryer with dehydrated air: a technical and economic viability analysisKonopatzki, Evandro A.Christ, DivairCoelho, Silvia R. M.Demito, AngélicaIvan, WernckeCamicia, Rafaela G. da M.http://www.sbicafe.ufv.br/handle/123456789/136432022-12-07T11:20:34Z2022-08-22T00:00:00ZCoffee dryer with dehydrated air: a technical and economic viability analysis
Konopatzki, Evandro A.; Christ, Divair; Coelho, Silvia R. M.; Demito, Angélica; Ivan, Werncke; Camicia, Rafaela G. da M.
The defects that drying in concrete yards impose on coffee beans and the search for gourmet coffee production have prompted the emergence of new drying technologies. This work verified the technical and economic feasibility of drying coffee with dehumidified air with a refrigerating capacity of 422,908.7 J s-1, compatible with static capacity dryers equal to 75 m3. Considering the sale price of coffee, the cost of electric energy acquisition, the monthly interest rate and maintenance time, expenses that are equivalent to the depreciation of the concrete yard, a central compound rotational design was considered with 28 tests for the feasibility analysis, including the internal rate of return, net present value and the return on investment. The results showed that in the electric drying units, the dried coffee presents fewer broken and defective beans and has higher retention in a No. 17 sieve. With a higher beverage quality and a price 12.11% higher, drying with dehydrated air showed a PBD of 2.27 years and a return of US$ 2.49 million. The optimisation results were 98.98% desirable. It was concluded that it is economically feasible to dry coffee with dehydrated air and without using a concrete yard.
2022-08-22T00:00:00ZNumerical approach for prediction of airflow behavior in coffee bean monolayers during dryng processBustos-Vanegas, Jaime DanielAragón, LarissaGutiérrez-Guzmán, NelsonCórdoba, Nancyhttp://www.sbicafe.ufv.br/handle/123456789/136422022-12-02T13:23:51Z2022-05-02T00:00:00ZNumerical approach for prediction of airflow behavior in coffee bean monolayers during dryng process
Bustos-Vanegas, Jaime Daniel; Aragón, Larissa; Gutiérrez-Guzmán, Nelson; Córdoba, Nancy
The homogeneity and efficiency of moisture removal from coffee beans depend on the airflow patterns inside the drying chambers used for drying. This study aimed to implement a porous medium model to simulate the airflow through mesh trays containing parchment and ripe fruit coffee ( Coffea arabica L.) using computational fluid dynamics (CFD). The geometry of the ripe fruit and parchment coffee beans was simplified as spherical and semi-ellipsoidal, respectively. The pressure drop in the normal direction to the monolayer was calculated as the average pressure of the normal planes located 1 mm before and after the bean layer for different air velocities. The viscous and inertial terms were adjusted by nonlinear regression for each case and incorporated into the Navier–Stokes equations as subdomains. The pressure drops calculated by the porous medium model and those calculated using the bean layers presented a good fit. The modeling of the trays as porous media can help reduce the computational resources required for CFD simulations while maintaining an acceptable accuracy.
2022-05-02T00:00:00ZMultivariate analysis applied to spray deposition in ground application of phytosanitary products in coffee plantsPalma, Roxanna P.Cunha, João P. A. R. daGuimarães, Ednaldo C.Santana, Denise G. deAssunção, Heli H. T. dehttp://www.sbicafe.ufv.br/handle/123456789/129112021-12-06T13:00:25Z2021-01-01T00:00:00ZMultivariate analysis applied to spray deposition in ground application of phytosanitary products in coffee plants
Palma, Roxanna P.; Cunha, João P. A. R. da; Guimarães, Ednaldo C.; Santana, Denise G. de; Assunção, Heli H. T. de
An adequate combination of factors involved in the technology used for phytosanitary product application contributes to an efficient spray deposition on the target. The objective of this study was to use multivariate analysis to characterize the magnitude of effects and the order of influence of three factors that interfere with the quality of phytosanitary product application in coffee plants. An entirely randomized design was adopted, with four repetitions, using a 2 × 2 × 3 factorial scheme, with two classes of droplets quality (fine and coarse), two application rates (250 and 400 L ha-1), and the use of adjuvants (with no adjuvant or with Fighter® and Aureo® adjuvants). The quality of the application was determined by jointly analyzing the spray deposition on three thirds of leaves, in their internal and external layers, the runoff to soil, coverage, droplet density, relative amplitude, and the volumetric median diameter. The results underwent analysis of variance (ANOVA) to measure the effect sizes (η2). After testing the assumptions of multivariate analysis, clustering and principal component analyses were performed. The class of droplets was found to be the most influential factor in the quality of the phytosanitary product application (spray deposition and runoff to soil). When focusing on spray deposition on leaves, the second-most influential factor was the application rate and the relation between the application rate and the adjuvants. For the other variables, the second-most influential factor was the application rate.
2021-01-01T00:00:00ZComparing a single-sensor camera with a multisensor camera for monitoring coffee crop using unmanned aerial vehiclesGomes, Amanda P. A.Queiroz, Daniel M. deValente, Domingos S. M.Pinto, Francisco de A. de C.Rosas, Jorge T. F.http://www.sbicafe.ufv.br/handle/123456789/129102021-12-06T13:00:23Z2021-01-01T00:00:00ZComparing a single-sensor camera with a multisensor camera for monitoring coffee crop using unmanned aerial vehicles
Gomes, Amanda P. A.; Queiroz, Daniel M. de; Valente, Domingos S. M.; Pinto, Francisco de A. de C.; Rosas, Jorge T. F.
There exist two options for digital cameras that can capture the near-infrared (NIR) band. Conventional red–green–blue (RGB, visible bands) cameras with a single sensor provide NIR band visibility based on the removal of the internal NIR-blocking filter. Alternatively, multisensor cameras exist that have a specific sensor for each band. The modified RGB cameras are of a lower price. In this context, the objective of this study was to compare the performance of a modified RGB camera with that of a multisensor camera for obtaining the normalized difference vegetation index (NDVI) in an area with coffee cultivations. A multispectral camera with five sensors and another camera with only one sensor were used. The NDVI of the coffee field was also measured using the GreenSeeker handheld NDVI sensor manufactured by Trimble. The images were calibrated radiometrically based on the targets in shades of gray made of napa, and the NDVI was calculated after image calibration. The calibration curves showed a high coefficient of determination. The NDVI value obtained with the calibrated images from the cameras showed a significant correlation with the values obtained by the GreenSeeker NDVI sensor, making it possible to obtain the variability pattern of the vegetation index. However, the NDVI obtained using the multisensor camera was closer to the NDVI obtained by the GreenSeeker NDVI sensor.
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