The results revealed that TOC was present in each of the fractions; therefore, further analysis was conducted to determine the distribution of organic carbon in LCGW. The phenols and their derivatives in the LCGW effluent accounted for 53.30% of the total COD, which reached 2712.36 mg x [L.sup.-1].
The polycyclic aromatic hydrocarbons and nitrogen heterocyclic compounds present in effluent are still difficult to degrade by biochemical treatment, despite the low level of phenols in the LCGW and good performance of biochemical technology at removing the phenols remaining in the effluent.
UV-Vis Spectral Analysis of DOM in LCGW before and after Ozonation.
The changes in 3D EEM spectra of LCGW treated by ozonation at different reaction times are shown in Figure 5.
Caption: Figure 5: 3D EEM of fractions in the LCGW. (a) HoA.