BAKER HUGHES - Drilling Fluids Reference Manual

Water Based Drilling Fluids
Filtration Control Agents
High filtration is characteristic of these fluids and almost any attempt to establish control results
in some deflocculation.
The materials used to reduce filtration are,
• BIO-LOSE ®
• BIO-PAQ ®
• CMC HV & LV
• MIL-PAC
• MIL-PAC LV
• MILSTARCH
BIO-LOSE
Addition of 5.7 to 11.4 kg/m 3 (2.0 to 4.0 lbm/bbl) is usually adequate for filtration control and
elevating low-shear rate viscosity. Although it contains no biocides, BIO-LOSE resists bacterial
degradation and is effective in both weighted and low-solids fluids over a wide pH range.
BIO-PAQ
Reduces filtration rate and increases low-shear rate rheological properties in brine systems
(seawater, NaCl, KCl, and high-hardness water-base fluids) where expected bottom hole
temperatures exceed 250°F. It also provides filtration control in divalent brines such as CaCl 2
and CaBr 2 . Recommended treatment is 1.0 to 4.0 lbm/bbl (2.85 - 11.4 kg/m 3 ).
CMC (HV or LV)
CMC will provide filtration control, though it is not as effective as MIL-PAC. The same
deflocculating effect has been observed.
MIL-PAC
MIL-PAC is an effective filtration control agent in KCl systems (0.5 to 1.0 lbm/bbl). It may
exhibit a deflocculating effect on rheological properties which could drastically reduce yield point
to plastic viscosity ratio.
MILSTARCH
In concentrations of 3 to 4 lbm/bbl, MILSTARCH has reduced filtration rates (15 to 20 cc) with
no appreciable deflocculation. In order to lower filtrate to the 5 cc range, 6 to 7 lbm/bbl of starch
are required.
Reference Manual
Baker Hughes Drilling Fluids
3-50 Revised 2006