The present work deals with the environmental sanitation of solid waste, focused on the
sludge generated at the North Sewage Treatment Plant (ETE-Norte) of Palmas-TO. The
responsible concessionaire, BRK Ambiental, performs the collection, treatment and final
destination of domestic sewage generated in the capital master plan, being the generating
source responsible for seeking the most appropriate method for the final destination of the
waste. Sludge is a solid waste generated in large quantities in the treatment of sewage, being a
problem in the environmental sanitation the final destination of this waste, since the presence
of heavy metals can pollute the soil and water sources. With the objective of minimizing
environmental impacts and suggesting a final disposal method with material utilization, the
work proposes to verify the physical and chemical characteristics of the sludge, determine its
calorific value and verify the pozzolanic reactivity of the ash. The waste generated in the
incineration process was considered a pozzolantic addition and included in the concrete
composition, being inserted in contents of 5 and 10% in the replacement of the Portland
cement in the concrete dosage. The comparative studies of the results of the reference
concrete and the concrete with sludge ash contents of the sewage treatment plant presented
satisfactory results that make feasible the use of the sludge as an input to the concrete, since
the analyzed specimens presented resistance to axial compression near the reference trace and
above the determined fck in the dosage. The tensile strength and modulus of elasticity are
satisfactory, compared to the standards. Regarding the ash, it was verified that there is a
pozzolanic reactivity, verified through the electric conductivity, in the thermal treatment by
incineration, the sludge presented high calorific value compared to other residues, making
feasible the use of the same as combustible material and making possible the use of the ash in
the concrete.
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