For a vessel with a 1,200-mm diameter, 1,350-mm straight side, 1,500-L capacity with a liquid viscosity 600 cp and specific gravity 1.0, and a 45-degree, four-blade, pitched-blade turbine operating at 600 rpm, the impeller should be 250 mm in diameter to create moderate mixing intensity with either four wall baffles in the tank or an angle-offset mounting to prevent swirling. The 250-mm diameter impeller needs a 2.0-kW motor and, therefore, a 32 Newton-meter torque drive.