Bentonite is a
ground clay consisting of hydratable minaral Montmorillonite.
2.APPLICATION
Bentonite is
used as a effective viscosifier and fluid loss reducing agent.It is most
effective in fresh water but can be used in sea water or salt brines if it is
prehydrated.
Bentonite may be
protected contamination by the addition of thiners or dispersants. The
compounds also minimise the high temperature gellation tendency shown by
bentonitic drilling fluids.
Due to the flat
platelike shape and small size of its particles, bentonites form a high level
of lubricity, thus reducing the torque on the drill string.
3.PHYSICAL AND CHEMICAL PROPERTIES
Appearance: Ligh yellow powder
PH: > 7
Solubility: Soluble in water
Toxicity:
Non-toxic
Bulk
density: 800-950 kg/m3(50-60lbs/ft3)
4.RECOMMENDED TREATMENT
Bentonite is
used as required to obtain the desired properties of drilling fluid. When
drlling through different zones and sections.
5.AVALUATION AS PER API-SPECIFICATION
SPECIFICATION
REQUIRED
OBTAINED
(Thuan
Phong)
Viscometer dial reading at 600 RPM
Yield Point/Plastic Viscosity Ratio
Filtrate Valume
Residue greater than 75 micrometer
Moisture
30 min
3 max
15 ml max
4.0 wt% max
10.0
wt% max
34
2.7
13.5
1.45
%
9.80
6.PACKAGING.
Bentonite is
packaged in net 50 kg/sack or as required.
