Although not specifically stated, a 2m diameter by 5m long tank must be a horizontal cylindrical tank. To provide good blending throughout a long tank will require two mixers, each positioned approximately 1.25m from the ends. The following design recommendations are based on typical mixing equipment that might be available in your area. Many small mixers will run at 300 rpm and two types of impellers may be readily available for them.  A 430mm diameter, 3-blade, narrow-blade hydrofoil impeller will require a 0.75KW motor.  A 330 mm diameter, 4-blade, 45deg pitched-blade impeller will also require a 0.75KW motor.

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