Table 15 Comparison of sludge heavy metal content with national standard limits.
“Sludge Disposal and Mixed Landfilling of Municipal Sewage Treatment Plants” (CJ/T 249–2007) (mg/kg) | Pb | Cr | As | Cd |
|---|---|---|---|---|
≤ 100 | ≤ 300 | ≤ 30 | ≤ 10 | |
Sludge cake (mg/kg) | 23 ± 0.36 | 18 ± 0.45 | 12 ± 0.35 | 0.55 ± 0.02 |
MCSP sludge cake (mg/kg) | 20.7 ± 0.40 | 16.1 ± 0.35 | 10.8 ± 0.30 | 0.50 ± 0.020 |
MCSP-TA sludge cake (mg/kg) | 19.1 ± 0.40 | 14.8 ± 0.35 | 10.0 ± 0.30 | 0.46 ± 0.020 |
“Water Quality Standards for Sewage Discharge into Urban Sewers” (CJ343-2010)(mg/L) | ≤ 1 | ≤ 1.5 | ≤ 0.5 | ≤ 0.1 |
Sludge filtrate (mg/L) | 0.029 ± 0.0015 | 0.024 ± 0.0015 | 0.040 ± 0.0020 | 0.059 ± 0.0025 |
MCSP sludge filtrate (mg/L) | 0.034 ± 0.0015 | 0.028 ± 0.0015 | 0.048 ± 0.0020 | 0.071 ± 0.0030 |
MCSP-TA sludge filtrate (mg/L) | 0.041 ± 0.0020 | 0.033 ± 0.0015 | 0.057 ± 0.0025 | 0.084 ± 0.0035 |
