Abstract
Zeolites are naturally occurring minerals characterized by high cation exchange and adsorption capacity and, thus, are used for metal uptake from sewage sludge subjected to composting process. In the present paper, changes in the physicochemical characteristics of sewage sludge samples after composting were recorded and analysed. The composting process was carried out for 120 days in pilot bioreactors, which were filled with 20% w/w clinoptilolite and sludge. The experimental results indicated differences in the metal content of the initial sludge and essential changes in pH, %Corg, % organic matter (OM), %N values and heavy metals content. Furthermore, the phytotoxicity tests that were performed showed that sludge samples affected seed germination and root elongation, but no phytotoxic effects were observed. According to the experimental results, it is concluded that the use of natural clinoptilolite leads to the improvement of the quality of the composted sewage sludge.
| Original language | English |
|---|---|
| Pages (from-to) | 240-249 |
| Number of pages | 10 |
| Journal | Desalination |
| Volume | 224 |
| Issue number | 1-3 |
| Early online date | 6 Feb 2008 |
| DOIs | |
| Publication status | Published - 15 Apr 2008 |
Funding
This paper has been prepared in the frame-work of the E.P.E.A.E.K. II Pythagoras project entitled Investigation and optimization of systems using natural zeolites and other mineral materials in environmental applications. The authors would like to express their gratitude to the Ministry of National Education and Religious Affairs of Greece which is financing all E.P.E.A.E.K II projects. The Project is co-funded by the European Social Fund (75%) and National Resources (25%).
Keywords
- clinoptilolite
- composting
- heavy metals
- sludge