Yemen, Fractured Granitic Gneiss
Open hole completion through fractures, high rates of H2S
AphronICS™ (Drill from surface to TD with AphronICS™ system)
Only the AphronICS™ system showed ability to maintain returns on on the value proposition. Gas entrainment was effective by maintaining hydrostatic pressure in the formation. Any H2S introduced in the system is scavenged by cations in the system or converted to soluble Sulfides due to alkaline nature of the buffered pH. Operators were able to use designed cement slurry to have problem-free cementing operations without losses.
Although the Aphron System was most expensive of the 4 methods operator reported cost efficiency due to reduced/eliminated losses, reduced water costs, problem free cementing, post well clean-up, little/no stimulation, and faster production times and better rates.