An investigation of new markets for the bagasse in Cuban sugar mills

Abstract: Historically, the production and exportation of sugar have been of immense significance for Cuba and although sugar remains to be the product of most vitality in the mills the diversification of sugar cane usage is now of a greater extent. This development has resulted in an increased production and consequently the mills provide by-products in a more considerable degree. The by-product of concern in this report is the sugar cane bagasse, which is used to fuel the boilers in the cogeneration unit in order to provide the electricity and heat needed for processing sugar. However, depending on the level of technological development within the mills, excess bagasse is being produced and by traditional terms causing a disposal problem. Conversely, the bagasse has vast potential within numerous different applications.    Carlos Baliño is situated in the province of Villa Clara and it is the only mill in Cuba that produces organic sugar. The mill is completely self-sufficient in its energy needs and moreover the mechanical steam turbines for the crushing and milling section have been exchanged to electrical drives and a bagasse boiler has been replaced by a more efficient one. These technological developments have resulted in excess bagasse being produced in a significant scale. The aim of the study presented in this report is to provide a suggestion of a suitable application of the excess by overlooking different ways of storing bagasse; pelletizing is one option that will be analysed. As the production of sugar and thereby bagasse is seasonal and the harvesting seasonality causes variations in the production the suggestion requires a numerical model that describes the nominal amount of excess bagasse in relation to the practical amount, based on the flows in the sugar mill. Furthermore, an economic evaluation of the chosen application with the aim of elucidating the potential of the stored bagasse as a source of income is presented in the report as well as an analysis of how the ash content affects the value of the bagasse.    Results showed that pelletizing is a suitable application for the excess bagasse at Carlos Baliño. The cost of capital for the considered pellet plant investment has been determined to 3,3 million USD and the breakeven investment cost to 4,7 million USD. Yet the economical calculations regarding the pellet plant investment have been based on a modest scenario it is profitable. Considering the vast difference between the nominal and the practical amount of excess bagasse Carlos Baliño has a great potential in increasing the amount of pellets produced as well as the financial gain.    Future work should suggestively focus upon improving the circumstances in which Carlos Baliño will produce and sell pellets in order to moreover enlarging the commercialisation scale of Cuban bagasse pellets. This report states the potential and the possibilities within the investigated market and can furthermore constitute the foundation upon which future studies regarding possible optimizations within the frames of the cogeneration unit with focus on the boiler efficiency, unplanned production stops as well as revenue based production optimization.