Saturated salt water mud

Saturated salt water mud means water based mud with high concentration of salt in the water. It contained a lot of chloride content until it reaches the saturated state and it has a dissolved salt more than 50,000 mg of salt per liter.

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Why do we use such a high concentration of salt in the water base mud?


This kind of mud is typically utilized in drilling into thick salt formations as salt domes. Moreover, it is used to control a hydrate problem in deepwater drilling.
Let’s talk about operation stand point of the saturated salt water mud
Practically, you can prepare the saturated salt by adding NaCl or KCl into base water until it reaches a saturation point. Then, some additives as fluid loss control, weighting material, viscosifiers, etc will be added later. When you freshly mix it, you need a certain amount of time to shear the mud until it has good rheology. Once you got the good rheology, this mud shows good Yield Point and gel strength. Since salt water has a chance to create foaming issue therefore you may need to add deformer to control this issue too. Additionally, you must remember that when you perform a retort test, you must subtract amount of salt from total solid otherwise you will get wrong figure for low gravity solid and high gravity solid from the retort test.

source : http://www.drilling-mud.org/saturated-salt-water-mud/