Estimativa dos ganhos socioeconômicos obtidos com a reciclagem de lixo. Usina de reciclagem e compostagem de lixo de Coimbra (MG) - estudo de caso.

Abstract

The production of urban garbage is one of the largest sanitary problems faced by the majority of brazilian Cities. The bad management of the solid residues may bring irreversible damages to the environment and to the public health. Garbage recycling and composting are shown as a good alternative to solve these problems. This work evaluated the viability of the Garbage Treatment System of Coimbra Municipality (MG) mainly because the employment of a pioneer technology developed in the Laboratory of Sanitary and Environmental Engineering Federal University of Vicosa (MG). The Executive Project, the current situation of the treatment sustem after a five years period and the socio-economic benefits were evaluated. The Executive Project was analysed through documents and registrations, obtained in Coimbra Municipal City Hall (MG) and from the Laboratory of Sanitary and Environmental Engineering Federal University of Vicosa (MG). To evaluate the currenty situation of treatment system a survey was made of the operating system in the rainy season (Feb/99) and dry period (Oct/99), the characterisation of the solid residues, mass balance, collection system, screening efficiency , system failure, and the quality of compost produced.To evaluate the socio-economic aspects related to the recycling and compositing a estimate of the savings with electric energy, raw material and water, obtained with the recycling of the inert materials (paper, plastic, glass, aluminium and metal), as well as the annual costs of the treatment was made. The population was intervened to verify their opinion regarding the garbage treatment sustem adopted and on several other subjects such: as from of conditioning of the domestic garbage in the residences, importance of the selective colection , level of information regarding the diseases associated with garbage, etc. The results showed that Garbage Treatment System of Coimbra (MG) is viable in all the aspects. The executive project was adapted to the reality of the municipal district. The system worked efficiently during the last five years. The total annual savings with electric energy, raw material and water reached significant values (R$ 77.440,30 and R$ 252.713,60, in the first and in the second phase respectively). The relationship revenue/cost was considered satisfactory (mainly in the second phase when 64% of the costs were covered with the sale of recycled materials compost), and the population was satisfied to possess a Garbage Treatment System, in the municipality.