No abstract

The Clean Development Mechanism (CDM) projects proposed in the Kyoto Protocol constitute an interesting way of protecting the environment and at the same time promoting sustainable economic development in emerging economy countries. Possible CDM projects include the treatment of swine manure using biodigestion, which would provide an opportunity for Brazil to actively participate in the carbon credits market. Brazil is currently the world's third leading swine producer (36 million animals). This study aims to demonstrate that the treatment of swine manure using bio digestion can minimize environmental impact and also contribute to reducing carbon dioxide emissions into the atmosphere by approximately 19 million tons per year, generating around US$ 78 million in carbon credits for Brazil annually.

The final disposal of urban solid waste has become a major concern in a world where urbanization is a trend. In this study three different systems were analyzed by accounting renewable, non-renewable and paid resources in a common basis, with the emergy accounting methodology, so it is possible to obtain ratios and indices that aid the comprehension, management and enable the comparison among the three system: landfill, pyrolysis and plasma arc. The systems are now operating, except for the arc plasma, which is under implementation in the municipality of Hortolândia-SP. The indices show that the landfill with electricity production is the system with better performance for 5 out of 6 indexes. For every gram of USW treated, the landfill can produce 1.78x1016 joules of electricity, which means that this system is 5 times more efficient than the pyrolisis and the plasma arc systems in this scope.