Topic Home
Sludge dewatering
An overview of sludge dewatering − an introduction to sludge dewatering theory and technologies
Lagoons
A lagoon is a large shallow reservoir with a sealed base which is filled with sludge, and the solids allowed to settle. Over a drying/dewatering operational cycle of several months, water is lost through evaporation while the solids form a thick layer at the base of the lagoon, stabilised by anaerobic biological processes
Topic
Introduction to sludge dewatering
Dewatering processes provide a concentrated, consolidated product along with a diluted stream which is predominantly water
Topic
Sludge drying beds and lagoons
Drying beds dewater sludge by allowing the liquid to drain and to evaporate. Lagoons provide dewatering through evaporation
Lagoons features and blogs
Feature
Co-processing of sewage digestate by hydrothermal carbonisation
Hydrothermal carbonisation (HTC) can be used to co-process anaerobic digestion (AD) digestate and lignocellulosic (or plant-based) feedstocks to improve the the hydrochar product quality. This AD waste co-processing route has been studied at bench scale. Read article
More Lagoons topics…
Discover
Belt filter presses
A belt filter press (BFP) dewaters sludge by pressing it between two revolving permeable belts to squeeze out the water
Discover
Centrifuges
Centrifugal dewatering consolidates sludge by encouraging particles to migrate to the walls of a rapidly rotating cyclinder
Discover
Drying beds
Drying beds dewater sludge by allowing the liquid to both drain from the sludge under gravity and evaporate from its surface
Discover
Filter presses
A filter press dewaters sludge by pressing it between a series of porous plates at high pressure to squeeze out the water
Discover
Rotary press
A rotary press dewaters sludge by passing it along a channel formed between two slowly-rotating circular permeable screens
Discover
Screw presses
A screw press dewaters sludge by passing it along the inside of an inclined permeable cylinder using an Archimedean screw
-
Conditioning
Conditioning is the pretreatment of sludge upstream of thickening and dewatering to promote solid-liquid separation
-
Thickening
Thickening processes concentrate the sludge by removing part of the free water, such that the product can still be pumped
-
Dewatering
Dewatering processes mechanically remove a significant proportion of the sludge water to produce a 15-45% cake product
-
Drying
In sludge drying the sludge moisture is removed as water vapour by heating, generating a pelleted or powdered product
More process and operation topics…
Discover
Sludge stabilisation
Sludge stabilisation − alkaline stabilisation, lime and solids dosing, plus anaerobic and aerobic digestion
Discover
Thermochemical processes
Thermochemical methods are used to either significantly reduce the sludge solids content or pre-treat sludge upstream of AD
Discover
Sludge quality
Sludge is the main waste stream from the treatment of wastewater