IMPORTANT HINTS ABOUT WATER BASED DRILLING MUD
Introduction To Water Based Drilling Mud .
The mud system used most frequently throughout the industry is the water-based system. Water is the continuous phase, but it may contain oil (i.e., emulsion muds) or air (i.e., aerated mud) as the discontinuous phase. The oil must remain as segregated droplets and not combine in a distinct phase termed "discontinuous" (Fig. 1).

 Fig.1
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