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Updated: Jul 18, 2026
11:14
Two-way Valorization of Blast Furnace Slag: Synthesis of Precipitated Calcium Carbonate and Zeolitic Heavy Metal Adsorbent
Published on: February 21, 2017
Utilization of dried sludge for making ceramsite.
1School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China. xgr@hit.edu.cn
Summary
This study demonstrates that dried sludge is a viable raw material for producing ceramsite, an effective filter medium for wastewater treatment. The developed ceramsite significantly improved removal efficiencies for turbidity, COD, and ammonia nitrogen in Biological Aerated Filters.
Area of Science:
- Materials Science
- Environmental Engineering
- Waste Management
Background:
- Sludge disposal presents environmental challenges.
- Ceramsite is a potential filter medium for wastewater treatment.
- Utilizing sludge in ceramsite production offers a sustainable disposal method.
Purpose of the Study:
- To investigate the feasibility of using dried sewage sludge in ceramsite production.
- To optimize the composition and sintering parameters for sludge-based ceramsite.
- To evaluate the performance of the produced ceramsite in treating municipal wastewater using Biological Aerated Filters (BAFs).
Main Methods:
- Component selection: dried sewage sludge, water glass, and clay.
- Optimization of component ratios and sintering conditions (temperature, time).
- Characterization of ceramsite properties (density, water absorption, porosity) using SEM, EDS, XRD, and XRF.
- Performance evaluation in BAFs for municipal wastewater treatment.
Main Results:
- Optimized process: 33% dried sludge/clay, 15% adherent/clay, 1000°C sintering for 10 min.
- Produced ceramsite properties: bulk density 582 kg/m³, particle density 1033 kg/m³, water absorption 9.5%, porosity 43.7%.
- Sludge-based ceramsite achieved high average removal efficiencies in BAFs: turbidity (96.4%), COD (76.2%), SCOD (59.6%), and NH3-N (82.3%), outperforming other media.
Conclusions:
- Dried sewage sludge is a suitable raw material for manufacturing ceramsite.
- The developed ceramsite exhibits favorable physical properties and excellent performance in wastewater treatment.
- This approach provides an effective method for sludge disposal and water purification.
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