Landfill Leachate Toxicity Removal in Combined Treatment with Municipal Wastewater

Table 2

Operational parameters of activated sludge systems I, II, and III.

Parameter	Unit	System	Range	Average±SD	Median
Sludge; loading; rate	g COD/; g MLSS·d	I: 1%	0.08–0.13	0.10±0.01	0.10
		I: 10%	0.11–0.15	0.11±0.02	0.11
		II: 1%	0.07–0.236	0.08±0.02	0.10
		II: 10%	0.08–0.23	0.15±0.03	0.17
		III	0.06–0.175	0.09±0.04	0.06
MLSS	g/L	I
		II	1.6–2.5	2.0±0.2	2.0
		III
Q	L/d	I
		II	8.5–10.0	9.5±0.5	9.7
		III
HRT	d	I		1.5±0.1	1.4
		II	1.4–1.6	1.6±0.4	1.5
		III		1.5±0.1	1.5

SD: standard deviation; number of measurements 𝑛=16; time-dependent variation caused by unstable composition of influent.
COD: chemical oxygen demand.
MLSS: activated sludge concentration.
Q: wastewater flow.
HRT: hydraulic retention time.