Dave Dickey Forum Moderator 282 Posts
Re: How do I build a mixer for a wide range of liquid detergents?10 November 2011 at 1:29pm
Your upper limit of 80,000 cp is questionable, since you need to have actual viscometer measurements to support such a value. If that value is accurate, then viscosity is likely to be non-Newtonian, as in shear thinning and possibly with a yield stress. Non-Newtonian properties only make mixing more difficult.
However, since you are dealing with a relatively small quantity, of about 150 liters, mixing is not impractical with large impellers and moderate speed. A reasonable recommendation is for a variable speed mixer with a maximum speed of 100 rpm and a 746 Watt motor. You will need three, 25 cm diameter, four-blade, 45 degree, pitched-blade impellers spaced at 15 cm increments on the shaft. That same speed range should work with the 1 cp liquid. The variable speed should be sufficient for fluid motion at all viscosities, although blending may be slow at the higher viscosities.
Propellers and hydrofoil impellers are not recommended. Although some wide-blade hydrofoils might work, but only at a higher speed range.
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