BAKER HUGHES - Drilling Fluids Reference Manual

MECHANICAL SOLIDS CONTROL
Some suggested guidelines for operation of barite recovery decanting centrifuges are:
1. Effluent viscosity – 35 to 37 sec/qt.
2. Effluent density – 9.5 to 9.7 lb m /gal. It may be greater if excessive quantities of barite are near
colloidal.
3. Underflow density – usually 20 to 23 lb m /gal. It may be less depending on volume of low-gravity
solids in the barite size range.
4.
5.
Bowl speed – 1600 to 1800 rpm
Dilution of feed fluid – 25% to 75% (10.5 to 11.5 lb m /gal). Dilution rate increases as viscosity
and density increase.
6. Process rate – see Figure 10-7.
7. Percentage of low gravity solids removed - normally 30% to 60%.
8. Chemical removal – underflow of decanting centrifuge will contain 15% to 30% of chemicals
present in original drilling fluid.
9. Volume decrease – 70% to 85% of fluid centrifuged. Depends on volume of solids in the
recoverable range.
10. ALWAYS WASH OUT THE CENTRIFUGE THOROUGHLY PRIOR TO SHUT DOWN
Figure 10-7) illustrates comparative processing capabilities for decanting centrifuges and
concentric cylinder (RMS) centrifuges.
Figure 10 - 7 Process Rate of Barite Recovery Decanting Centrifuge
BAKER HUGHES DRILLING FLUIDS
REVISION 2006 10-17
REFERENCE MANUAL