Q5. In a paint factory, titania particles in 300 um sizes as pigment are mixed with...

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Q5. In a paint factory, titania particles in 300 um sizes as pigment are mixed with water to obtain a suspension at 25°C. For this purpose, an unbaffled mixing tank in 2 liters suspension capacity is used in the laboratory. Volume fraction of titania particles in the suspension is 5%. Densities of titania and water are 4000 and 1000 kg/m3, respectively. Viscosity of water is 1 cP. A six flat blade turbine type impeller is used with 500 rpm speed. For this mixing system (Fig. Q5.1), Figure Q5.1. Unbaffled tank Calculate a) the dimensions of the laboratory scale mixing tank [5 pts]. b) density and viscosity of the suspension (mixture) (4 pts). c) the power required for the laboratory mixing tank (Hint: consider the system as if it is a miscible system) [10 pts). d) the power required for a pilot mixing tank in 0.5 tons capacity and its impeller speed. Assume geometrical similarity and power per unit volume is identical in potn laboratory and pilot scale mixing [6 pts] Q5. In a paint factory, titania particles in 300 um sizes as pigment are mixed with water to obtain a suspension at 25°C. For this purpose, an unbaffled mixing tank in 2 liters suspension capacity is used in the laboratory. Volume fraction of titania particles in the suspension is 5%. Densities of titania and water are 4000 and 1000 kg/m3, respectively. Viscosity of water is 1 cP. A six flat blade turbine type impeller is used with 500 rpm speed. For this mixing system (Fig. Q5.1), Figure Q5.1. Unbaffled tank Calculate a) the dimensions of the laboratory scale mixing tank [5 pts]. b) density and viscosity of the suspension (mixture) (4 pts). c) the power required for the laboratory mixing tank (Hint: consider the system as if it is a miscible system) [10 pts). d) the power required for a pilot mixing tank in 0.5 tons capacity and its impeller speed. Assume geometrical similarity and power per unit volume is identical in potn laboratory and pilot scale mixing [6 pts]