No Parameter Unit Range of concentrations in petroleum wastewater Average The standard discharge limit
1 pH - 6-8 7 6-9
2 Conductivity Micro S/cm

2600-3950

3275 2000-2700
3 TDS ppm(mg/L)

1200-1500

1350 1500-2000
4 TOC ppm (mg/l) 220 - 265 243 50 - 75
5 COD ppm(mg/L) 550-1600 1075 150-200
Table 2: Characteristics of the petroleum wastewater from Sohar oil refinery (SOR).