Research Article
Nursery Growing Media: Agronomic and Environmental Quality Assessment of Sewage Sludge-Based Compost
Table 1
Physical and physicochemical characteristics of sewage sludge.
| Parameter | Value in dry sewage sludge (SS) | Limit value in dry SS (according to Italian Legislation Lgs D. 99/1992) |
| Colour | 7.5Y 2/1 | | Moisture content (%) | 11.8 | — | Total OM (%)a | 42.3 | — | Oxidizable OC (%)a | 21.9 | ≥20.0 | pH (H2O) | 7.64 | — | EC (dS m−1) | 4.10 | — | C : N ratio | 6.12 | — | CaCO3 | 19.8 | | CHA/CFA | n.d. | — | Total Kjeldahl Nitrogen TKN (%)a | 3.21 | ≥1.50 | P2O5 (%)a | 1.91 | ≥0.40 | K2O (%)a | 0.21 | — | CEC (cmol(+) kg−1) | n.d. | — | Pb (%)a | 49.0 | 750 | Cd (%)a | 5.21 | 20.0 | Ni (%)a | 24.0 | 300 | Zn (%)a | 1057 | 2500 | Cu (%)a | 216 | 1000 | Hg (%)a | 5.10 | 10.0 | Cr+6 (%)a | 1.20 | — |
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Values on a dry matter basis; data are mean values, .
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