Metodologias para gerenciamento de lodo de ETA e ETE

Abstract

The integrated solid waste management assumes that the waste generated in water treatment plants (WTP) and wastewater treatment plants (WWTP) must be sent to an environmentally friendly final destination. The aim of the present thesis is to propose methodologies based on Geographic Information Systems (GIS), linear optimization and simulation by the System Dynamics approach (SD), as means to assist both the WTP and the WWTP sludge management. Four methodologies were proposed based on tabulate and vector data from several sources, softwares of GIS and simulation, and calculus spread sheet. The first methodology consists of overlaying potential areas for the application of sludge with WTP and WWTP clusters. A subsidiary methodology for identification of land feasibility to receiving WWTP sludge was developed. The second methodology uses GIS for determining the distances among several treatment plants and the potential sites for sludge application. The amount of sludge for each reception site was defined by solving a linear optimization problem. The third methodology consisted of elaborating a SD model to assist the sludge management in a WTP, by simulating the costs of sanitation systems as a function of time. The fourth methodology integrated the three previous methods to determining the feasibility of sludge management units (SMU) implementation. Exception for the first method, all methodologies showed to be robust enough to support the decision makers from sanitation companies and can be applied for individual as well as pool management of sanitation residues. It can be stated that the tools used individually have lower potential than when used together. Therefore for better decision making subsidized on sludge management WTP and WWTP, the joint use of different technological tools is essential. In order to evaluate the methodologies the basins of the rivers Piracicaba, Capivari and Jundiaí, were used as a case study. It was verified that a lack of qualitative and quantitative data availability was the biggest problem for the adoption of the methods by sanitation companies. It is essential to have a survey plan and organization of data: operating costs of water and wastewater treatment; quantification and characterization of materials and wastes in treatment plants. The combination of methodologies presented in this work allows the execution of the detailed analysis of the optimal solution of sludge disposal within a territorial unit, as well as simulation of complex sludge management systems costs, subsidizing robustly the managers decision making of sanitation companies. The techniques used are replicable and can be applied to different territorial units that need an integrated waste management plan.