Relative Coagulation Effectiveness of <i>Jatropha curcas</i> Press Cake (Physic Nut) and Aluminium Sulphate in Purifying Domestic Sewage

• Main Authors: Kamoru Akanni ADENIRAN, F. A. AKINWUNMI
• Format: Article
• Language: English
• Published: University of Agricultural Sciences and Veterinary Medicine, Cluj-Napoca 2016-09-01
• Series: Notulae Scientia Biologicae
• Online Access: http://www.notulaebiologicae.ro/index.php/nsb/article/view/9849

An investigation was conducted on the relative effectiveness of using press cake of dried Jatropha curcas (Physic nut) seed and alum (Aluminium sulphate) for the purification of domestic sewage. The experimental design used was Completely Randomized Design (CRD) replicated three times. Physical and chemical properties of domestic sewage were investigated before and after the purification exercise. Treatments imposed included: the control culture (no alum and Jatropha), 10 mg/l of Aluminium Sulphate (alum) treatment, 80 mg/l of J. curcas treatment, 100 mg/l of J. curcas treatment and 120 mg/l of J. curcas treatment. The results showed that for the total dissolved solids, cultured tanks treated with 80 mg/l of J. curcas reduced the sewage concentration from 30.1 mg/l to 23.20 mg/l, Biological Oxygen Demand (BOD) was reduced from 30.55 mg/l to 30.10 mg/l, increased acidity from 5.33 mg/l to 5.66 mg/l, reduced alkalinity from 6.35 mg/l to 6.0 mg/l, reduced pH from 7.6 to 6.55, and likewise 10 mg/l of alum also reduced pH from 7.6 to 6.55. The cultured tanks treated with 120 mg/l of J. curcas performed best in reducing turbidity and Chemical Oxygen Demand (COD) of the sewage. The turbidity was reduced from 5.99 NTU to 5.6 NTU; 120 mg/l of J. curcas also reduced total hardness from 9.6 mg/l to 7.15 mg/l, total solids from 55.6 mg/l to 55.17 mg/l. Cultured tanks treated with 10 mg/l of alum reduced total dissolved solids from 30.1 mg/l to 24.30 mg/l, while those treated with 80 mg/l of J. curcas reduced it from 30.1 mg/l to 23.20 mg/l, 100 mg/l and 120 mg/l of J. curcas reduced it to 25.20 mg/l. Total suspended solids increased from 25.5 mg/l to 30.96 mg/l for 10 mg/l of alum, to 30.22 mg/l for 80 mg/l of J. curcas, 30.26 mg/l for 100 mg/l of J. curcas and 30.38 mg/l for 120 mg/l of J. curcas. Conductivity increased withion the study period from 525 μS/cm to 830 μS/cm for 10 mg/l of alum, to 590 μS/cm for 80 mg/l of J. curcas, 634 μS/cm for 100 mg/l of J. curcas and finally to 662 μS/cm for 120 mg/l of J. curcas. The results show that, within the reduction of BOD, pH, alkalinity and total solids, 80 mg/l of J. curcas performed best, while for reduction of COD and turbidity, 120 mg/l of J. curcas gave the best results. The study showed that Jatropha curcas was effective in purifying domestic sewage with little or no harmful effect on the ecology.