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CLEAN PRODUCTION: EFFICIENCY AND ENVIRONMENT * * Paper presented at the seminar “The sugarcane: a multidimensional agenda for 21th century”, 25th –29th October, in Dominican Republic, organized jointly by FAO and GEPLACEA AUTHORS: Electo Silva Lora Felipe Ponce Arrieta Ricardo Carrasco Carpio Luiz Augusto Horta Nogueira THERMAL SYSTEMS STUDY GROUP Department of Mechanics - DEM FederalEngineering School of Itajubá – EFEI Av. BPS 1303, CP 50, Itajubá /MG, CEP 37500-000 – Brasil E-mail: electo@iem.efei.br

I- Introduction The first documented mention about sugar cane, appeared in the Hindu sacred book, Atharva Veda, and is dated from a period estimated between the years of 5000 1000 before Christ. Christopher Columbus in his second journey brought sugar cane to the American continentand planted it in “La Española” island. However, its industrial utilization for sugar production began at the end of the 16th century in Cuba and other Caribbean islands. In 1528 copper mines were discovered in Santiago de Cuba and the first fusion was carried out in 1599 with the establishment of a Spanish Government State Company. This allowed the manufacturing of the "machinery" for the firstsugar cane mill. It is not casual that Mr. Francisco Sánchez de Moya, the first "Manager" of this metallurgic company, was the owner of 3 of the first sugar cane mills in the American continent. In 1617 there were already 37 sugar cane mills between Santiago de Cuba and Bayamo, the first sugar cane mills in Jamaica and Haiti appeared at this same time. The sugar industry enters its fifthcentennial within a complex context. On one hand the reduction of the sugar prices seems to be an irrevocable tendency. On the other hand, the intensification of the use of sugar cane as a renewable energy source is vital, considering its contribution to the solution of global environmental problems and the exhaustion of fossil fuels reservatories in a near future. The main objective is to found, thepossibility of sustainable development of sugar cane industry in the 21st century and its relationship with energy efficiency and environmental management aspects in the sector. II- The sugar cane industry and the clean production. First, let us see the concept of clean production firstly (C+P): "it is a preventive integrated strategy applied to processes, products and services in order to increase theefficiency and reduce the risks for the human beings and the environment. For the processes, a clean production includes the efficient use of the raw materials, water and energy, the elimination of toxic products, and the reduction of emissions and residues in

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the source. It also deals with the decrease of the environmental impact of the products, promoting friendly designs according tothe necessities of future markets." (Centro Nacional de Producción más Limpia, 1998). Analyzing the activity of diversified sugar cane agro-industry, some important elements could be indicated in order to reach a clean production in this sector: • • • • • • • Implementation of green sugar cane mechanized harvest; Control of soil erosion and salification; Implementation of alternative methods fordistillation stillage treatment; Reduction of the sector own environmental impacts through the implementation of prevention and control programs; Reduction of water consumption in the mill and the use of zero-effluents type systems, with total water recuperation; Reduction of environmental impacts caused by the energy and fuel sectors by substituting considerable quantities of generated electricitywith liquid fuels of fossil origin; Environmental improvement of extensive regions and sugar cane producing countries.

The attainment of a clean production in the sector is attached to the efficiency increase of several agricultural and industrial process stages: • The increase of the agricultural yield. At Present, in the range of 40-60 tc/ha.year in the majority of the producer countries,...