Sulfitação: um estudo de caso em uma usina no interior do estado de São Paulo

Abstract

Brazil is one of the biggest sugar producers in the world, which is due to the tropical climate that the country experiences. The raw material for this product is sugarcane. Its quality is directly connected to conditions of cultivation and maturation to which it is submitted, because due to climate, type of harvest and microorganisms, sucrose in sugarcane can be lost. Sucrose is sugar from sugarcane that can be crystallized, and in order to make it possible, sugarcane juice goes through several unit operations to be clarified and subsequent crystallization of sugar.Among the operations, sulphitation stands out, which is the determining stage of obtaining white crystal sugar. Bleaching happens through the absorption of sulfur dioxide (SO2) by sugarcane juice, where several reactions occur to eliminate the impurities present in the solution. The aim of this work was to study the sulphitation operation in a sugar cane and alcohol plant in the countryside of the state of São Paulo, and besides improving the operation, it was sought to observe the parameters and understand their influence on the efficiency of the process. First, in the field, the possible problems that impacted on the formation and absorption of sulphite in the sugarcane juice were analyzed. Then, in the laboratory, a methodology of determination of sulphite in the sugarcane juice was applied, as well as observation of other parameters, such as temperature and pH in samples collected during the process. From the results obtained it was possible to understand the influence of the temperature on the formation of the sulfur gas, and by monitoring of the sulfur dosage, it was concluded that, in a comparison between the previous and the current harvest, there was a better control of the operation and greater color classification.