A Comparative Study of the Use of Cassava Species and Alum in Waste Water Treatment

Abstract

This research was conducted to study the performance of two varieties of cassava as coagulants in waste water treatment and compare them with alum. Heavy metals composition of the two varieties of cassava used were also studied. The results showed that, the acid treated portion of specie A (Manihot palmate) recorded 51.8 % turbidity reduction efficiency and 70 % reduction in alkalinity; while for the untreated portion of specie A recorded 60 % reduction in alkalinity. The acid treated portion of specie B (Manihot aipi) recorded a 58.3 % reduction in turbidity and 80 % reduction in alkalinity; while the alum reduced the turbidity by 43.7% at the dosage of 50ml. The untreated portion of specie B, showed 80 % reduction in TSS and a 70 % reduction in alkalinity. The heavy metals contents of the two species of cassava were obtained as: Cu (0.077 µg/g), Cd (0.000 µg/g), and Zn (0.231 µg/g), Ni (0.168 µg/g), Mn (8.516 µg/g) and Pb (0.144 µg/g) for specie A and Cu (0.086 µg/g), Cd (0.000 µg/g), Zn (0.258 µg/g), Mn (9.624 µg/g) and Pb (0.047 µg/g) for specie B; while the heavy metals contents of the wastewater were: Cu (0.036 mg/l), Cd (0.056 mg/l), Zn (0.269 mg/l), Ni (0.000 mg/l), Mn (0.505 mg/l) and Pb (0.137 mg/l). It was concluded that the two cassava species were more effective than alum as coagulants in wastewater treatment.http://dx.doi.org/10.4314/njt.v33i2.5