Quantification of complete cycle water treatment plant sludge production: a critical assessment

ABSTRACT

Most of the water treatment plant (WTP) residuals generated in Brazil are still discharged into water bodies, or disposed in landfills. However, especially in large urban areas, ever-stringent environmental legislation and rising logistical costs have put focus into beneficial uses for those residuals. To evaluate the possible beneficial uses, beyond the knowledge of qualitative characteristics of the residuals, operators and designers should be able to predict, with some degree of certainty, its mass and volume. The objectives of this work are: to compare the performance of two of the main quantitative estimation methods for residuals production - the empirical formulas and the mass balance; to investigate the widespread practice of estimating the concentration of total suspended solids using turbidity as a surrogate; and to identify the conditions under which such procedure is acceptable.

Keywords:
water treatment; drinking water; residuals; sludge production.