Related Experiment Video
Updated: Jul 22, 2026

Extraction of Structural Extracellular Polymeric Substances from Aerobic Granular Sludge
Published on: September 26, 2016
Lightweight aggregate made from sewage sludge and incinerated ash
Ing-Jia Chiou1, Kuen-Sheng Wang, Ching-Ho Chen
1Department of Civil Engineering, Nanya Institute of Technology, Graduate Institute of Environmental Engineering, National Central University, 414, Sec. 3, Chung-Sun E. Road, Chungli, Taoyuan 320, Taiwan, ROC. Jessie.chiou@msa.hinet.net
Abstract:
In this study, sewage sludge ash (SSA), with similar characteristics to expansive clay, was used as the principal material and sewage sludge (SS) as the admixture to sinter lightweight aggregate and to study the influences of raw material composition on pelletising, sintering effect and aggregate properties. Results showed that both SS and SSA could be sintered to produce synthetic aggregates individually or mixed. Increasing the amount of SS would decrease the pelletising ratio. Under the consideration of energy saving, the mixture of SSA was better for sintering normal weight aggregate. On the contrary, the mixture that added 20-30% of SS was more adequate to make lightweight aggregates. Adding SS would enhance the oxidation-reduction reaction and lower the bulk density and sintering temperature of aggregates to save energy. Sintering temperature affected the properties of sewage sludge ash lightweight aggregate (SSALA) more than retention period did. Prolonging the retention period could improve bloating effect.
Related Concept Videos
Pozzolans
Fly ash is a...
Aggregates Classification
Petrographic classification groups aggregates based on common mineralogical characteristics. Some of the common mineral groups found in aggregates are...
Deleterious Substances in Aggregate
Another type of impurity is clay and fine material that...
Preplaced Aggregate Concrete
Additives and Fillers in Concrete
The...
Design Example: Aggregate Gradation
The grading, or particle-size distribution, of sand is determined using sieve analysis, with standard sizes ranging from 150 μm to 10 mm (ASTM No. 100 sieve to 3⁄8 in. sieve). Sand is sampled...

