The following conclusions are drawn

The following conclusions are drawn from the experimental study conducted on treatment of tannery wastewater using
natural coagulants:
1) Tannery wastewater has the characteristics ; pH-5.5, Color-Dark brown, COD- 28,000 mg/l, BOD-8,000mg/l,
Total solids-15,200mg/l, Dissolved solids-6,650 mg/l, Suspended solids8,550mg/l, Turbidity-66 to 960 and all
the parameters are more than the permissible limit.
2) The optimum dosage of Cicer aretinum, Moringa oleifera and Cactus seed powder as coagulant is found to be
and 0.1gm/500ml, 0.3gm/500ml and 0.2gm/500ml.
3) The optimum pH in coagulation process for Cicer aretinum, Moringa oleifera and Cactus seed powder at
optimum dosage is found to be 5.5, 4.5 and 5.5,respectively.
4) Increasing dosage of Moringa oleifera lead to decrease in turbidity upto the optimum dosage after which the
residual turbidity increases due to floc restabilization.
5) Among the three natural coagulants used in the study, maximum turbidity reduction is found to be 82.02%
with Moringa oleifera.
6) Among the three natural coagulants used in the study, maximum COD reduction is found to be 90.00% with
Cicer aretinum.
7) As it is observed that Cactus opuntia is consistant in turbidity reduction of almost above 60.00% for all COD
concentrations. Hence it is concluded that cactus opuntia has the potential to be utilized for tannery wastewater
treatment.
8) Among the three natural coagulants used in the study, Cicer aretinum has the COD reduction of 90.00% and
turbidity reduction of 81.20%.Hence it is concluded that as compare to other two coagulants Cicer aretinum is
the effective coagulant in treating tannery wastewater.