The Mastersizer 2000 particle size analyser from Malvern Instruments is proving to be a valuable aid in formulating drilling muds that couple high performance with minimal environmental impact
This fully automated system measures particles in the range from 0.02 to 2000 microns.
Suitable for a wide range of sample types, it allows the straightforward measurement of both aqueous and non-aqueous drilling muds.
The particle size of the solid components used in drilling muds is directly linked with the product functionality.
Initially, muds were used to cool and lubricate the drill bit and remove debris from the drill hole, while also controlling the hydrostatic pressure in the well.
However, by controlling the particle size, muds can also help maintain hole stability and prevent fluid invasion into permeable rocks.
This is particularly true when drilling shales, where fluid invasion not only threatens hole stability, but also causes significant pressure loss during well operation.
Here, selection of the correct mud system can lead to the formation of a mud cake across the surface of the bore hole, bridging any pore structures and improving shale inhibition.
Using the Mastersizer 2000, researchers are able to optimise the mud properties relative to the nature of the geological formulation being drilled.
Size analysis can be carried out for each of the mud components, including weighing, bridging and rheological control agents.
Optimising the particle size reduces the solids loadings required to achieve specific performance targets.
