Table 2 Characteristics of wastewaters from each full-scale step feed WWTP

Temp (°C)

27.1 ± 0.1

27.4 ± 0.2

–

25.2 ± 2.0

25.1 ± 2.5

–

pH

7.4–7.6

7.2–7.4

–

7.0–7.2

6.9–7.1

–

SS (mg L^− 1)

36 ± 2

6 ± 1

83 ± 2

127 ± 16

14 ± 2

88 ± 0.5

BOD (mg L^− 1)

35 ± 2

6 ± 1

83 ± 2

126 ± 21

10 ± 2

91 ± 0.1

COD (mg L^− 1)

73 ± 5

18 ± 2

75 ± 1

275 ± 24

30 ± 2

89 ± 0.2

NH₄⁺ (mg L^− 1)

13.3 ± 0.2

2.3 ± 0.4

83 ± 6

21 ± 2.5

8.6 ± 1.4

59 ± 5

NO₃⁻ (mg L^− 1)

0.4 ± 0.1

5.2 ± 0.5

–

0.20 ± 0.08

0.5 ± 0.04

–

NO₂⁻ (mg L^− 1)

0.1 ± 0.05

0.02 ± 0.01

78 ± 11

0.04 ± 0.02

0.02 ± 0.01

50 ± 1

Organic-N (mg L^− 1)

4.4 ± 0.1

1.9 ± 0.16

57 ± 3

4.2 ± 1.71

1.5 ± 0.9

67 ± 8

TKN (mg L^− 1)

17.7 ± 0.3

4.2 ± 0.56

76 ± 3

25.2 ± 4.2

10.1 ± 1.0

60 ± 3

TN (mg L^− 1)

18.2 ± 0.4

9.4 ± 2.1

48 ± 10

25.4 ± 4.3

10.6 ± 2.4

59 ± 2

TP (mg L^− 1)

3.0 ± 0.2

1.9 ± 0.1

37 ± 4

2.9 ± 0.8

1.5 ± 0.7

48 ± 12