APHRON-BASED DRILLING FLUIDS: SOLUTION FOR LOW PRESSURE RESERVOIRS
Journal Title: UNKNOWN - Year 2009, Vol 21, Issue 1
Abstract
Drilling wells throughout depleted or low pressure reservoirs requires low density drilling fluids, often with density less than water. Methods to reduce the density of drilling fluids have included mixing-in air or nitrogen. However, problems with these approaches include instability of gas bubbles (bubbles collapse or expand) and increased costs. Recently, the use of micro bubbles named aphrons in drilling, completion and workover fluids has proven success in solving many problems related to low pressure reservoirs such as fluid loss control, formation damage, stabilization of multipressure sequences with one fluid and possible differential sticking. Aphrons represent bubble with uniquely structure stabilized with surfactant. Against conventional micro bubbles, aphrons are more stable in downhole conditions and they are generated using standard mixing equipment. Owing to their properties and overpressure in wellbore aphrons penetrate into low pressure layers and set up inner bridging. Depleted wells which are very expensive to drill underbalanced or with other remediation techniques can now be drilled overbalanced. This paper presents description of aphron structure and stability, aphron bridging mechanism, aphron-based fluid composition and properties, and field experiences in applying aphron-based fluids.
Authors and Affiliations
Nediljka Gaurina-Međimurec Borivoje Pašić
Keywords
Related Articles
- EP ID EP30001
- DOI -
- Views 158
- Downloads 1
VELIKE VODE NA SLIJEVU GORNJE DOBRE
U radu su na osnovi podataka s četiriju postojećih hidroloških stanica na slijevu Gornje Dobre razmatrani osnovni hidrološki pokazatelji. Definirane su i grafički prikazane krivulja učestalosti i krivulja trajanja srednj...
MIDDLE MIOCENE DROWNED RAMP IN THE VICINITY OF MARIJA BISTRICA (NORTHERN CROATIA)
Fossiliferous Middle Miocene deposits from the surroundings of Marija Bistrica (north-east of Zagreb) transgressively overly older pre-Cenozoic bedrocks. Fossils from shallow marine environments are in most cases preserv...
ISTRAŽIVANJE VODE U OBALNOM KRŠU METODOM DVOJNOG GRADIJENTNOG KARTIRANJA
Dvojnim gradijentnim kartiranjem prividne električne otpornosti provedeno je istraživanje vode na nekoliko lokaliteta krškog obalnog pojasa Jadranskog primorja. Ovom metodom, kojom se prati odnos otpornosti po dubini uz...
PROGNOZA ODVALA U TUNELIMA PREMA GEOLOŠKI DEFINIRANIM RAVNINAMA DISKONTINUITETA
Inženjerskogeološki podaci moraju biti adekvatno pripremljeni za kasniju provjeru stabilnosti podzemnih prostorija. Srednje vrijednosti smjera i nagiba ravnina diskontinuiteta nisu mjerodavne, nego granice područja tih k...
GEOLOGY AND GEOCHEMISTRY OF THE MINERALIZATION FROM THE GORNJI VAKUF AREA, BOSNIA
In the Gornji Vakuf area, which is built up of Palaeozoic sediments and metarhyolites, the authors investigated 47 ore occurrences by geological and different geochemical methods. They distinguish; (a) alluvial, diluvial...