Discussion regarding the management of Water Treatment Plant (WTP) sludge have been
guided in several meetings and scientific papers in recent decades. The constant population
increase, tied to technological development evidenced in recent years, has contributed
significantly to increase the sludge generation, especially those produced in WTP. Sludge
management is, therefore, a problem at the environmental, social and financial level, and has
as one of the main stages the dewatering techniques, procedure responsible for volume
reduction, stabilization of the solid phase and reuse of the liquid phase. Therefore, the use of
geotextile tubes as dewatering technology has been widespread in WTPs, although there are
still few studies that address the parameterization of projects and the ideal type and dosage of
chemical conditions for each WTP. Therefore, the present work aimed to evaluate, from the
implementation of bench tests, the performance of the process of sludge dewatering of a water
treatment plant by geotextile pipes, considering the simulation of several concentrations of
Total Suspended Solids (TSS) and chemical conditioning agents. Bench tests outcome showed
that the initial TSS concentration of sludge and the dosage of the non-ionic chemical
conditioning influenced the retention of solid material by the geotextile fabric and the
dewatering time. Bench sludge dewatering tests, both pressurized and by gravity obtained the
best turbidity results when applied dosages of 1.5 mgPol/gTSS with a sludge at TSS
concentrations ranging from 2.5 g/L to 18.5 g/L. In polymer concentrations above 6
mgPol/gTSS, physical changes of the filtered liquid were evidenced and an increase in filtered
liquid turbidity values. It was also evidenced, retention of 13% of the solids content inside the
geotextile tube for sludge with a concentration of 2.5 g/L and 17.4% and 14.5% for slats at
concentrations of 10.5 g/L and 18.5 g/L, respectively. The results obtained from the
experimental planning show the technical feasibility of dewatering WTP sludge through a
geotextile tube. However, real-scale tests should be performed to confirm the results obtained
on the bench tests, real-scale tests should be performed.
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