Fig. 1
Leaching efficiency of P, Al, Ca and Fe with different 1 M acids at phase ratio 20 mL g−1, for (a) chemical sludge and (b) biological sludge
Fig. 1 | Sustainable Environment Research
Leaching efficiency of P, Al, Ca and Fe with different 1 M acids at phase ratio 20 mL g−1, for (a) chemical sludge and (b) biological sludge