Abstract:
One of the most hazardous pollutants to the environment is those produced
from the industrial activities, and tanneries are one of the sources of the
environmental pollution for their production of toxic and carcinogenic
wastes such as chromium. The main objective of this study was to assess the
performance of the industrial wastewater treatment plant of White Nile
tannery. The performance was evaluated in terms of the characteristics of the
wastewater disposing in the sewage network after passing through the
primary treatment plant, such as biological oxygen demand(BOD) ,chemical
oxygen demand(COD),total suspended solid(TSS),total dissolved
solid(TDS) ,oil and greases ,PH, and chrome(Cr).the results obtained
showed that the minimum concentration of BOD ,COD, TDS and pH after
treatment are ( 620 , 1600,5820 mg/l and 7) respectively, these values
doesn't meet the requirement of the Sudanese standards for the disposal of
industrial wastewater in the sewage network except the TSS, the maximum
concentration of TSS it is 340 mg/l . So the high values of BOD and COD
after treatment compared with the standard limits indicate that the biological
treatment is not efficient, therefore The BOD and COD removal efficiency
should be increased by mixing sewage with industrial wastewater to increase
the amount of microorganisms, and the duration of treatment should be
increased also from 16 hr to 32 hr to reduce concentrations of organic
pollutants, but the sedimentation process works efficiently according to TSS
values. There is a variation in Cr values, some values meet the requirement
of the Sudanese standard and others are higher than the allowable limit,
therefore, there is a need for a unit in the treatment plant to recover the
chromium (Cr) and reuse of it in the tanning process again.