Viabilidade econômica da compostagem do lodo de esgoto para uso agrícola

The objective of this work was to evaluate the economic viability of composting of sewage sludge mixed with two carbon sources: sugarcane bagasse or eucalyptus bark for producing organic fertilizer in a commercial scale at the Sewage Treatment Station (STS) in the city of Botucatu - Sao Paulo. The economic analysis was accomplished with process monitoring, data collection and cash flows elaboration from which the following indicators were extracted: Net Present Value (NPV), Internal Rate of Return (IRR), Discounted Payback Period (DPP) and Cost Benefit Ratio (RCB), which allowed us to conclude that the alternative the most viable economics was the one that used sugarcane bagasse, with revenue from organic fertilizer commercialization and as a benefit, the cost savings with transportation and disposal of sewage sludge in sanitary landfill.