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The coag-flocculation performance of Mucuna Seed Coagulant as affected by pH variation in coal washery effluent has been investigated at room temperature using various dosages of unblended Mucuna Seed Coagulant. In addition, coag-flocculation parameters such as Coagflocculation reaction order α, α th order coag-flocculation constant K, Collision factor for Brownian Transport β Br, Smoluchowski constant K R, , Collision Efficiency ε p, and Coagulation Period τ 1/2 were determined. Turbidity measurement was employed using the nephelometric (turbidimetric) standard method while Mucuna Seed Coagulant preparation was adopted from the works of Adebowale and Adebowale (2007). The maximum Mucuna Seed Coagulant parameter performance is recorded at α of 2, K of 8.3334 x 10-3 m 3 /kg.s, dosages of (0.15 kg/m 3 ; 0.2 kg/m 3 ; 0.25 kg/m 3); pH of 6 and τ 1/2 of 1.7339 sec while the minimum parametric performance is recorded at α of 1; K of 6.3001 x 10-4 s-1 ; dosage of 0.2kg/m 3 ; pH of 8 and τ 1/2 of 1100.2161seconds. The minimum value of coag-flocculation efficiency E (%) recorded is greater than 88.00 %. Conclusively; Mucuna Seed Coagulant is an effective coagulant obeying the theory of fast coagulation at the conditions of the experiment.

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Model for evaluation of the concentration of dissolved phosphorus (relative to the final pH of the leaching solution) during leaching of iron oxide ore in oxalic acid solution has been derived. It was observed that the validity of the model is rooted in the relationship lnP = N/α where both sides of the expression are approximately equal to 4. The model depends on the value of the final pH of the leaching solution which varies with leaching time. In all, the positive or negative deviation of the model-predicted phosphorus concentration from its corresponding value obtained from the experiment was found to be less than 22%, which is quite within the acceptable deviation limit of experimental results hence establishing the validity and precision of the model.

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Model for predictive analysis of the concentration of phosphorus removed (relative to the initial and final pH of the leaching solution) during leaching of iron oxide ore in sulphuric acid solution has been derived. It was observed that the validity of the model is rooted in the mathematical expression; (P/N) 1/3 = (e γ/α ) where both sides of the relationship are almost equal. The model; P = 4.25(e γ/α ) 3 shows that the concentration of phosphorus removed is dependent on the values of the initial and final pH of the leaching solution. In all, the positive or negative deviation of the model-predicted phosphorus concentration from its corresponding value obtained from the experiment was found to be less than 29%, which is quite within the acceptable deviation limit of experimental results hence establishing the validity and precision of the model in its application for predicting quantitatively the concentration of phosphorus removed during the leaching process.

Factorial optimization and kinetics of coal washery effluent (CWE) coag-flocculation by Moringa oleifera seed has been investigated at room temperature based on standard method of bench scale jar test. Moringa oleifera coag-flocculant (MOC) was produced according to work reported by Ghebremichael. A 2 3 full factorial central composite design was employed for the experimental design and analysis of results with respect to optimization. The combined effects of pH, dosage and settling time on the particle (turbidity) removal were studied using response surface methodology. Kinetic data generated were confronted with specified kinetic models for the evaluation of functional kinetics parameters. The optimal values of pH, dosage and settling time were recorded at 8400 mg/l and 25 min, respectively. The results of the major kinetic parameters recorded are 20.002 l/mg·min, and 0.79 min for order of reaction, coag-flocculation reaction rate constant and coagulation period, respectively. The minimum removal efficiency recorded was 95% at 3 mins of coag-flocculation. The results, while re affirming MOC as efficient coag-flocculant, confirmed that theory of perikinetics holds for the studied system at the conditions of the experiment.