Influence of Harvester and Rotation of the Primary Extractor Speed in the Agroindustrial Performance of Sugarcane

This study aimed to evaluate the amount of vegetable and mineral impurities, and the industrial quality standards of the sugarcane, under different harvester speeds and rotations of the primary extractor, in the first cut from a sugarcane field in a terrain with 7% declivity. The experiment took place in the city of Pacaembu, in the western region of the State of São Paulo, Brazil. The space between plant rows was 1.4 m, and the field had an estimated productivity of 75 t ha −1 and low weed incidence. The sugarcane variety planted was RB96-5902, and the treatments were the combination of two harvester speeds (3 and 6 km h −1 ) and two primary extractor rotation speeds (700 and 1200 rpm). Besides, the standard speed of 5 km h −1 and 950 rpm, commonly used by the industry, was used as control treatment, which made a total of 5 different treatments analyzed. The response variables studied were vegetable impurities (IV, %), mineral impurities (IM, %), total impurities (IT, %), fiber (%), brix, pol (%), corrected sugarcane pol (PCC, %), apparent juice purity (PZA, %), reducing sugars (AR, %) and total recoverable sugars. According to the results obtained, the factor, which presented major influence over the level of impurities and the technological characteristics of the raw matter, was the rotation speed of the primary extractor. In this scenario, the highest rotations decreased the impurity levels and improved the industrial qualities. Considering the treatments applied, the most efficient rotation speed was at 1200 rpm.