EVALUATION OF ORGANIC AND INORGANIC COAGULANTS IN MITIGATING WATER TURBIDITY OF CLAY BASED EARTHEN POND

Abstract

The study was to evaluate the effects of organic and inorganic coagulants in mitigating turbidity in earthen pond water due to clay. Turbid water was collected from Pacific farm. Plastic bowls were filled with 25litres of turbid water with clay particles. Alum, Gypsum, Ash of rice straw each were placed separately into the bowls at dosages of 0.2,0.4,0.6,0.8 and 1.0g/25l while bale of hay of rice straw (BHR)was applied separately at the rates of 100, 150, 200, 250 and 300g/25l. The contents were stirred vigorously for 1-2 minutes at intervals of 5 minutes for 30 minutes, allowed settling and readings of physicochemical parameters were taken after 10 minutes. The same experiments were replicated three times. Thedata obtained were analysed using non-parametric ANOVA. Alum, Gypsum, and BHR revealed that the mean values of pH, conductivity and total dissolved solid (TDS) increased with increased rate of application generally. However, the results for Ash revealed that the mean values of the physicochemical parameters decrease with increased dose. Temperature (250C) remains constant in all the treatments. The range values of pH (6-8.7667), TDS(830-1198) and conductivity (1296.9-1871.9µS) across the treatments; Bioassay of catfish in treated water showed that fish were active at dosages of Alum (0.6- 1.0g/25l);Gypsum (0.8 and 1.0g/25l) and BHR (100-300g/25l). Turbidity of water could be mitigated by applying appropriate dosages of Alum, Gypsum, BHR. Further research is recommended for lower and higher dosages of BHR and Ash respectively to convert waste rice straws to wealth