Zero Discharge Performance of an Industrial Pilot-Scale Plant Treating Palm Oil Mill Effluent
Table 5
Effluent characteristics of reclamation system comparing standards of boiler feed water and drinking water.
Parameter
Ultrafiltration (UF)
Reverse osmosis (RO)
Boiler feed water standard (Drum pressure 31.1–41.1 bar)
Drinking water standard
pH
8.61
7.53
7.5–10.0
6.5–8.5
Color, color units
85
1
NR
15
Odor, threshold odor number
32
ND
NR
3
Turbidity, NTU
3.2
0.2
NR
<0.5
Specific conductance, S/cm
4792
295
2500
NR
Total dissolved solids (TDS), mg/L
3389
307
NR
500
Silica, mg/L (SiO2)
1.42
0.95
40
NR
Total alkalinity, mg/L (CaCO3)
1926
96
250
NR
Oil and grease (O and G), mg/L
ND
ND
0.5
0.3
DO, mg/L
1.76
1.62
0.007
NR
Total hardness, mg/L (CaCO3)
792
0.15
0.2
NR
Total organic carbon (TOC), mg/L
193
0.3
0.5
NR
Al, mg/L
ND
ND
0.1
0.05–0.2
K, mg/L
1983
59
NR
NR
Mg, mg/L
164
0.04
0.25
150
Ca, mg/L
39
ND
NR
NR
Fe, mg/L
0.99
ND
0.03
0.3
Mn, mg/L
0.32
ND
0.1
0.05
Cu, mg/L
0.01
ND
0.02
1.0
Zn, mg/L
ND
ND
NR
5
Note: ND: not detectable; NR: not required; the transmembrane pressures (TMP) for UF and RO membrane were maintained at 2 bars and 13 bars, respectively.
