RETORT / SOLIDS ANALYSIS

The retort apparatus is used to determine the amount and type of solids and liquids present in a drilling mud sample. Mud is placed in the steel container and then heated until the liquid portion is vaporized.
The vapor is passed through a condenser in which it is cooled, and then collected in a graduated cylinder.
•The volume of the water and oil is measured as a fraction of the total mud volume.
•For accurate results, a true mud density should be used for calculations, an accurate air free sample must be used, and a volume correction factor should be determined for oil content if it is present in the mud.
Test Procedure
•Lift the retort assembly from the insulator block. Using a spatula as a screwdriver, remove the sample cup from the retort chamber.

•Pack the upper chamber with fine steel wool, or add 5-6 drops of “liquid steel wool”to the mud in the sample cup.
Test Procedure
•Fill the lower sample cup with a freshly stirred mud sample, and replace the calibration lid, allowing any excess to escape.
•Wipe off any excess mud and screw the lower sample cup (with calibration lid still in place) into the upper chamber, maintaining both upper and lower chambers in the upright position. Screw condenser onto the outlet hose of the upper chamber Test Procedure
•Replace the retort assembly in the insulator block, and close the insulating cover.
•Add a drop of wetting agent (Aerosol) to a 10 cm3or 50 cm3graduated cylinder (depending on the size of retort being used), and place it under the drain of the condenser.
Plug in the retort and turn it on. Continue heating until liquid no linger drips from the condenser.
When using a thermostat retort, the light will go out at the end of the test
Solids Calculations
•Most retorts are only accurate to within 1.0-2.0%. For that reason, most low solids muds, i.e.: muds with low mud densities that contain no Barite, salt or oil, use the following formula to calculate the volume fraction of solids:

•Volume Fraction of Solids (% Solids) = [(Mud Weight (kg/m3) / 1000) –1] X 0.625
Solids Calculations
•If a Baroid Retort is used, read the volume of oil and water. Calculate the fractions as follows if a 10 cm3retort is used:

•Fo(volume fraction of oil) = cm3oil / 10
•Fw(volume fraction of water) = cm3of water / 10

•Fs (volume fraction of solids) = 1.00 –total liquid fraction


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