Reservoir Souring Tracking; Evaluation & Management to De-Eisk the Development Activities in a Giant Carbonate Reservoir in North Kuwait

Abstract

Sabiriyah Mauddud is a giant carbonate reservoir in North Kuwait under active development with water flooding by treated seawater. Reservoir souring occurring at multiple producers has added one more dimension of complexity to be tracked; evaluated & managed. The paper proposal aims to elaborate the challenges and associated mitigations conceived & implemented. Comprehensive evaluation of all data available pertaining to reservoir souring has been done, based on which a field-wise sampling program has been embarked. The sampling program has been executed in phases in a rationalized manner to provide necessary data & inputs to the overall evaluation using analytical as well as simulation approach. Workflow process has been developed so that the tracking, evaluation & management of reservoir souring continues as a live project during the water flood development for Sabiriyah Mauddud. A clear linkage has been observed between the injected volumes of seawater and the level of souring. A review of chemicals being used for inhibition of souring indicated that the bacteria becomes insensitive to the dosage used in the past and requires re formulation of the package of chemical dosage. The impact on flowlines and production facilities has been found to be nominal so far but likely to aggravate with time. The possibility of using sour competent metallurgy in future has been flagged for future budgeting, to be first implemented in the facilities with most of Mauddud producers flowing. Any new facility has been recommended with NACE specifications. A continuous tracking & monitoring of the Reservoir souring lead to opportunistic solutions & mitigations for short-term production & long-term reservoir management requirements with HSE adherence.