Análise de fluxo de materiais em uma usina sucroalcooleira na Paraíba

Abstract

The sugar-energy sector in Brazil is on a constant path in the modernization process, through the incorporation of new technologies with a view to achieving greater productivity and profit. However, to maintain growth in the market, it is necessary for the plants to increase productivity by knowing the inputs, stocks and outputs of materials, as well as the environmental impacts caused in their processes. The first objective is to apply the Material Flow Analysis (AFM) methodology to assemble a flow diagram associated with the production of sugar, ethanol and bioenergy to determine losses. The second objective is to apply a Life Cycle Assessment (LCA) methodology to quantify greenhouse gas (GHG) emissions associated with surplus electricity generated and sold. The study was carried out at a plant in the state of Paraíba, but the name will not be disclosed. In order to conduct the research, it was necessary, in addition to searching for data in the scientific literature, through an exploratory research, the use of SimaPro® software to develop the LCA along with the IPCC 2013 GWP 100a method to quantify the GHG emitted. As a result, AFM revealed the total amount of losses considering an entry of 7,000 t/day of sugarcane into the plant. In the preparation and manufacturing stage, a sugar loss of 38.50t was identified. In the broth filtration stage, there was a loss of 1,779t of sugar in the filter cake, in the fermentation process to obtain ethanol, there was a loss of sugar of 48.01t, in the distillation stage the loss of ethanol was 1,480.38L. From an environmental point of view, GHG emissions associated with the generation of bioelectricity amounted to 0.224 kg CO2-eq/kWh generated, preventing 132 kg CO2-eq from being emitted into the atmosphere. Both the AFM and the ACV proved to be effective in the development of the analysis, emphasizing that it is necessary to use methods to carry out the monthly mass balancing and bringing into focus the use of the maximum potential of by-products such as filter cake and vinasse, preventing the use of fertilizers that significantly contribute to greenhouse gas emissions.