Osmosis in OBM

Dear all

Please can you let me know your experiences of potential osmotic reaction when using OBM mud (typically 85/15 oil-water ratio) to drill through shale/clay sections and whether it makes it necessary to maintain the chloride content, besides that needed for electric stability of the OBM.

In our case, the chloride content in OBM is more than 250K mg/l, whilst some reactive shale may need around 350K mg/l if there is a risk of osmosis.

I´d appreciate any feedback you have.

Many thanks

Dany Rizska
Drilling Engr
PT Medco E&P
Jakarta, Indonesia

8 Answer(s)

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