Avaliação da influência do tempo de deslodamento no desempenho operacional de uma centrífuga industrial de gelatina tipo B

Abstract

Clarification is an important stage in industrial gelatin production, as it contributes to the removal of suspended particles and to the operational stability of subsequent filtration steps. This study aimed to evaluate the influence of partial solids-discharge time on the operational performance of an industrial disc-stack centrifuge used in Type B gelatin processing. The study was conducted under industrial operating conditions using bovine hide split as the raw material. Three programmed partial solids-discharge times were evaluated: 1100 s, 1200 s, and 1300 s. For each condition, samples were collected at the centrifuge outlet at approximately 10%, 55%, and 90% of the period between discharge activations, representing the beginning, middle, and end of the interval. Samples of the gelatin solution before entering the centrifuge were also collected. Turbidity was considered the main response variable, while pH and °Brix were used as complementary parameters. The data were treated by calculating the arithmetic mean and sample standard deviation. The 1100 s condition showed the lowest mean turbidity values at the centrifuge outlet. However, this condition was also associated with lower inlet turbidity and operation closer to the recommended flow-rate range of the equipment. Greater variability was observed for the 1200 s and 1300 s conditions, mainly due to flow rates above the operational capacity, equipment shutdowns, failures, and process interruptions. Therefore, it was not possible to establish a single partial solids-discharge time capable of consistently ensuring the lowest outlet turbidity. As an improvement proposal, the installation of inline turbidimeters at the centrifuge inlet and outlet is suggested, allowing the feed condition and clarification performance to be continuously monitored. Recording these measurements together with the operating conditions and production type would support the definition of reference ranges and control limits. A hybrid control strategy is also recommended, in which outlet turbidity may anticipate partial solids discharge, while a maximum time between discharges is maintained as a safety condition.