The aim was to assess the ability of microcosms
(laboratory-scale shallow ponds) as a post polishing stage
for the remediation of artificial textile wastewater comprising
two commercial dyes (basic red 46 (BR46) and reactive blue
198 (RB198)) as a mixture. The objectives were to evaluate
the impact of Lemna minor L. (common duckweed) on the
water quality outflows; the elimination of dye mixtures, organic
matter, and nutrients; and the impact of synthetic textile
wastewater comprising dye mixtures on the L. minor plant
growth. Three mixtures were prepared providing a total dye
concentration of 10 mg/l. Findings showed that the planted
simulated ponds possess a significant (p < 0.05) potential for
improving the outflow characteristics and eliminate dyes,
ammonium-nitrogen (NH4-N), and nitrate-nitrogen (NO3-N)
in all mixtures compared with the corresponding unplanted
ponds. The removal of mixed dyes in planted ponds was
mainly due to phyto-transformation and adsorption of BR46
with complete aromatic amine mineralisation. For ponds containing
2 mg/l of RB198 and 8 mg/l of BR46, removals were
around 53%, which was significantly higher than those for
other mixtures: 5 mg/l of RB198 and 5 mg/l of BR46 and
8 mg/l of RB198 and 2 mg/l of BR46 achieved only 41 and
26%removals, respectively. Dye mixtures stopped the growth
of L. minor, and the presence of artificial wastewater reduced
their development.
م. د. دينا علي ياسين | Dr. Dina Ali Yaseen | 3785