Innovative Cement Packer Deployment without the Associated Skin: A Niger Delta Case Study

Abstract

The use of cement packers to access behind-pipe hydrocarbon opportunities has opened up significant reserves without the attendant cost of a rig. A key challenge with this technique is the attendant high skin that results from the cement packer which significantly impacts initial production rates and recoverable reserves. The objective of this paper is to share technique and lessons from a case study in a mature field, offshore Niger Delta where an innovative technique was employed to place the cement packer above the perforation interval in the target reservoir. This eliminated the skin due to the cement packer, leading to significantly higher initial production rates when compared to analog workovers. The paper details operational procedure during execution. The lack of a local precedent in the deployment of this type of cement packer presented a key challenge. Perforating the target reservoir and string without impacting the second string in the wellbore was another challenge. The initial production rate from the case study was 2200 BOPD vs 800 BOPD or less from analog cement packer workovers. A key lesson learned is that this solution is best suited to wellbores with a single production string only or multiple strings wellbores in which there is no further production utility for the additional strings. The follow on best practice from this lesson is to fully evaluate the wellbore utility for any identified opportunity of this sort to ensure the deployment of this method does not impede the utility of the wellbore for future reservoir management operations.