Evaluation of Centrifugal Pumps in a Silage Feed Processing Plant for Pigs/Evaluacion de las bombas centrifugas en una planta procesadora de alimento ensilado para cerdos

The work was carried out with the objective of determining how often the centrifugal pumps for industrial silage production have to work in the "Héctor Molina" plant of the Municipality of San Nicolás de Bari in Mayabeque, Cuba. That technology was developed by the Institute of Animal Science (ICA) and it uses by-products and wastes from the sugar industry and agricultural production for animal feed. To determine the frequency, the sedimentation rate (v) of the solids in the liquid raw materials (thermolised Saccharomyces cerevisiae yeast cream, concentrated vinasse) and the silage feed was calculated. For that, three experiments were carried out, each one with 10 graduated test tubes. Initial height of each test tube and height of descendant interfaces at different time intervals were measured and the behavior of the variable sedimentation vs. time was analyzed with statistical criteria. It was obtained that the (v) of the vinasse, cream and silage are 1,58 [E.sup.-6] m / s, 2,76 [E.sup.-07] m / s, and 1,55 [E.sup.-07]m / s, respectively. It is concluded that the centrifugal pump must recirculate the vinasse and the cream to maintain a stable chemical composition every 4 h and 12 h. The silage should be recirculated every 58 h to facilitate the extraction of the final product from the silos and the model that best describes the sedimentation of CSF is the quadratic model. Keywords: sedimentation, silage, centrifugal pumps, recirculation. El trabajo se realizó con el objetivo de determinar con qué frecuencia tienen que trabajar las bombas centrífugas para la producción de ensilado a escala industrial en la planta "Héctor Molina" del Municipio San Nicolás de Barís en Mayabeque, Cuba. Tecnología desarrollada por el Instituto de Ciencia Animal (ICA), que aprovecha subproductos y desechos de la industria azucarera y de las producciones agrícolas, para la alimentación animal. Para determinar la frecuencia se calculó la velocidad de sedimentación (v) de los sólidos en las materias primas líquidas (crema de levadura Saccharomyces cerevisiae termolizada, vinaza concentrada) y el alimento ensilado, para esto se realizaron tres experimentos cada uno con 10 probetas aforadas, se midieron la altura inicial de cada probeta, la altura de interfases descendientes a diferentes intervalos de tiempo y se analizó el comportamiento de la variable sedimentación vs tiempo con criterios estadísticos. Se obtuvo que la (v) de la vinaza, la crema y del ensilaje son de 1,58 [E.sup.-