In preparing a bentonite slurry using fresh water, the bentonite will hydrate and agitation furnished by a mixer is sufficient to separate the hydrated clay plate lets and result in a viscosity and gel strength increase, if the bentonite is placed in salty water or water containing dissolved hardness (calcium or magnesium) the hydration and subsequent dispersion by agitation is reduced.
EFFECT OF ADDING BENTONITE ON MUD PROPERTIES FOR FRESH AND SALT WATER BASE MUD:
Mud rheology refers to the mud of deformation and flow behavior of all forms of matter. Certain rheologic measurements made on fluids, such as viscosity, gel strength, etc. help determine how this fluid will flow under a variety of different conditions. This information is important in the design of circulating systems required to accomplish certain desired objectives in drilling operations.
Viscosity is defined as the resistance of a fluid to flow and is measured as the ratio of the shearing stress to the rate of shearing strain.