Mud solids

Permeable intervals can be identified from a number of logging tool measurements, the most basic of which is the caliper tool. The caliper tool is used to measure the borehole diameter which, in a gauge hole, is a function of the bit size and the mudcake thickness. Mudcake will only build up across permeable sections of the borehole where mud filtrate has invaded the formation and mud solids (which are too big to enter the formation pore system) plate out on the borehole wall. Therefore the presence of mudcake implies permeability. 

With increased development work from offshore platforms, more non-vertical (deviated) wells are being drilled. Settling of mud solids to the low side of the well bore can result in a continuous channel of undisplaced drilling mud solids in the casing annulus... 

Solids Wetting. In most crude oil, solids such as iron sulfide, silt, clay, drilling mud solids, and paraffin complicate the demulsification process. Often such solids are the primary stabilizing material, and their removal is all that is necessary to achieve satisfactory treatment. To remove solids from the interface, they can either be dispersed in the oil or water-wetted and removed with the water. 

In his 1963 novel Cat s Cradle, author Kurt Vonnegut conjures up a new form of water, "ice-nine," sought by generals wishing to turn mud solid to speed their troops to battle. The problem is solved by an isolated, scientific genius who makes a tiny quantity of the dangerous substance, innocently starting the count-down to the end of all life on Earth. Since "ice-nine" is more stable than water, any water it touches (puddles, lakes, reservoirs, oceans, rain) E>ecomes "ice-nine" and all liquid water vanishes from the planet. 

In highly permeable formations with large pore throats, whole mud may invade the formation, depending on mud solids size. 

Use bridging agents to block large opening, then mud solids can form seal. 

Applications booster propellant (binder), epoxy modifier, drilling mud, solid rooket propellant, toughening agent In dental compositions Mante, F K VUadenya, R 0 Blenstock, DA Mendelson, J LaFleur, E E, Dental Mater., 26, 164-8,2010. 

Mud cake permeability (darcies) . lOOOE-05 Mud cake porosity (decimal nbr) . lOOOE+00 Mud solid fraction (decimal nbr) . 3000E+00 Viscosity of invading fluid (cp) . lOOOE+01 Viscosity, displaced fluid (cp) . 2000E+01 Pressure at well boundary (psi) . lOOOE+03 Pressure, effective radius (psi) . OOOOE+00 Radius of the well bore (feet) . 5000E+00 Reservoir, effective radius (ft) . lOOOE+02 Rspurt > Rwell radius t=0 (ft) . 6000E+00 Maximum allowed number of hours . lOOOE+07... 

Rock core permeability (darcies) Rock core porosity (decimal nbr) Mud cake permeability (darcies) Mud cake porosity (decimal nbr) Mud solid fraction (decimal nbr) Viscosity of invading fluid (op) Viscosity, displaced fluid (op) Pressure at left boundary (psi) Pressure at right boundary (psi) Length of rook oore sample (ft) Initial "xfront" position (feet) DX grid size in rock sample (ft) DX grid size in the mudcake (ft) Integration time step size (seo) Maximum allowed number of steps... 

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