Mixers and agitators

Agitated Line Mixer See Fig. 18-32. This device, which combines the features of orifice mixers and agitators, is used extensively in treating petroleum and vegetable oils. It is available in sizes to fit V2- to 10-in pipe. The device of Fig. 18-33, with two impellers in separate stages, is available in sizes to fit 4- to 20-in pipe. 

Mixers and agitators designed for flammable liquids or dusts should be constructed to minimize fire and explosive possibilities. Electrical equipment should follow the requirements of Uie National Electrical Code. Equipment should be bonded and grounded to prevent Uie accumulation of staUc electricity. 

Turbine driven pumps blowers Mixers and agitators Simple Incinerators Flare stacks... 

Table 18.1 identifies common failure modes and their causes for mixers and agitators. Most of the problems that affect performance and reliability are caused by improper installation or variations in the product s physical properties. 

Table 18.1 Common faiiure modes of mixers and agitators...

Proper installation of mixers and agitators is critical. The physical location of the vanes or propellers within the vessel is the dominant factor to consider. If the vanes are set too close to the side, comer, or bottom of the vessel, a stagnant zone will develop that causes both loss of mixing quality and premature damage to the equipment. If the vanes are set too close to the liquid level, vortexing can develop. This will also cause a loss of efficiency and accelerated component wear. 

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