A Novel Non-damaging Approach to Isolate Open hole Lateral that Allowed Performing Mechanical Descaling in the Non-Monobore Cased Completion: A Case Study in Saudi Arabian Carbonate Reservoir

Autor: Nestor Molero, E.V. Rivadeneira, A.E. Mukhliss, Ataur R. Malik, Tolulope M. Ogundare, Alaa A. Dashash
Rok vydání: 2014
Předmět:
Zdroj: All Days.
Popis: Mechanical descaling of iron sulfide scales in high angle non-monobore or horizontal open hole completion offer multifaceted challenges, especially when the reservoir is depleted. The history of the descaling program in carbonate gas wells in Saudi Arabia dates back to 2007. The program suffered several setbacks with operational complexities like stuck pipe, H2S generation (souring) during chemical dissolution and severe induced damage during reservoir isolation process. The depleted reservoir needs to be isolated to ensure full circulation during mechanical descaling process. The mechanical means of isolation with a bridge plug is not feasible due to the presence of FeS scale in the wellbore. The only isolation option available at the moment is CaCO3 chips bullheaded from the surface. Often the post-descaling and stimulation operation does not restore the original production, due to the heavy damage induced in the reservoir during isolation. This paper shares a successful descaling experience and best practices in a single lateral open hole well that was completed with 4-1/2-in tubing and 7-in liner, and had severe pressure depletion. A novel non-damaging visco-elastic surfactant based fluid was used to fill the open hole lateral and as base to support CaCO3 chips above it that prevented additional damage and allowed reservoir isolation for mechanical descaling, using high pressure coiled tubing and a jetting tool. A clean wellbore with no further induced damage made subsequent post-stimulation results very attractive. The paper also presents the production results of stimulation treatment performed after the descaling treatment.
Databáze: OpenAIRE