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Oil production from North Kuwait carbonate reservoirs are challenging because of factors, such as high permeability streaks, poor microscopic sweep efficiency, and low mobility ratios, all of which can dramatically impair production rates and oil recoveries. Despite tremendous efforts related to waterflood research, oil recovery in carbonates typically remains low. New technology and approaches are required to increase and sustain oil production to access and drain immense amounts of remaining oil-in-place.This paper presents the results of collaborative work procedures applied to a selective number of wells to increase production performance in the Sabriyah Mauddud field pilot under the Kuwait Integrated Digital Field (KwIDF) project umbrella. KwIDF is part of a comprehensive strategy undertaken by an operator to enhance overall oil production by the application of digital oilfield (DOF) concepts, which involves (1) well instrumentation to provide enhanced real-time data availability, (2) upgraded power and communications infrastructure to support field instrumentation and control real-time data, (3), creating collaborative decision centers to enhance asset team processes across physically separate locations, and (4) providing a platform to increase effectiveness through automating work processes and to shorten observation-to-action cycle time.The Sabriyah KwIDF pilot involves 44 producer and five injector wells producing about 7% of total Sabriyah field production. The main objective of this effort was to maximize and sustain oil rates and reduce well decline while honoring safe well operating envelope constraints. As a result of this effort, production gains have been certified in 10 wells of the pilot area to date. This success has been achieved by carefully analyzing past performance and adjusting well settings to realtime production conditions using the operator's digital infrastructure.This paper describes how this optimization methodology provides improvements to short-term production rates while honoring safe well operating envelope and presents case histories illustrating the benefits from the automated workflows and collaborative decision approach. The average sustained oil gain was 395 BOPD, or 37%. The total sustained oil gain reached 3,949 BOPD (34%), with a cumulative production gain of 756 thousand barrels for the evaluation period.

North Kuwait has planned EOR activities to boost ultimate recoveries in multiple reservoirs. The reservoir with the highest priority on the EOR activity Gantt chart is Alkaline Surfactant Polymer (ASP) flood for Sabiriyah Mauddud due to significant incremental recovery estimated based on past SWCT tests. Prior to the initiation of ASP injection, slated pilot area is under intensive plumbing for insights into the inter-well connectivity. The paper proposal aims to share the actions taken up, analysis done and tracking of dynamic data for the area located within & adjacent to the EOR pilot area. Data acquisition for the pilot area wells (4 injectors; 2 observation wells & 1 producer) has been done in two phases — (a) during the drilling of the wells, cores/ RFT pressures/ Log suites/ PVT samples have been taken and (b) during the injection of sea water into the EOR pilot injectors, time lapse pressure-production data/ surveillance information & tracer sampling/ analysis have been done to understand the inter-well connectivity; flag the uncertainties and de-risk the EOR pilot as a preparatory background for studies & ASP injection. Connectivity between wells within the pilot & surrounding area under active water flood has been established. Pathways for quick fluid/ flux movements have been identified and calibrated with the petrophysical data. Tight zones or compartments within the pilot area have been examined. Uncertainty regarding thief zones within & outside the pilot area has been evaluated. A comprehensive data integration indicates that continuing with ASP injection will be optimal, with minimal losses/ escape to the area outside the 5-spot EOR pattern. De-risking the upcoming ASP injection via proper data acquisition, interpretation & integration during the preliminary water flood flushing stage is one of the best industry practice.

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractLower Burgan reservoir is a giant multi layered reservoir in Sabiriyah field of North Kuwait operating under active bottom water drive as well as edge water drive. The reservoir is on production since 1960s and has so far produced about 63% of the original reserves. The effective reservoir management by innovative tracking of water movement, identifying segments with bypassed oil, opportunistic well workovers, prudent selection of infill well targets and continuous reservoir monitoring have made it possible to sustain the reservoir production rate near to the projected plateau and carry it forward for next 4-5 years.

Sabiriyah Mauddud is one of the largest carbonate reservoirs in North Kuwait on active water flood since last 20 years using sea water as the injectant. The reservoir is purely a depletion drive reservoir, responding to water flood quickly in terms of increase in reservoir pressure as well as preferential flow of injectant into the nearby producers, thus stressing the existing water handling capacities at the gathering centers. Almost 40% of the injected water re-circulated between the injectors & producers, thus disabling the complete benefit of the ongoing water flood activities. A new initiative has been tried at two of the injectors for cyclic injection for optimal balance between pressure requirements and water cut levels. While water flooding Sabiriyah Mauddud, surprises in terms of rock & fluid understanding influenced quick water cut build up, reaching to more than 90% in some wells. A comprehensive G&G; Reservoir engineering and surveillance data aided to understand the connection factors between the injectors and producers. A fit for purpose tool developed to evaluate the water re-circulation has been used to short list the wells with "bad" water, requiring attention to control. As such bad water had been mainly due to direct short circuiting with the nearby injectors, team decided to go for handling such water from injector management point of view rather than working over the well for conformance related isolation of water producing zone. Cyclic water injection is the best solution so as to minimize the water re-circulation and stay within the operating range of the ESP in the associated producers, with properly spaced cycles of closure & opening. The initiative has been implemented at two of the injectors recently with positive results. The cyclic injection has reduced the water cut at the associated producers up to 30%, thus improving the oil cut significantly. This has reduced the water handling requirements at the gathering centers. The closing action planned for few high water cut wells has been canceled as a result of this strategy. The concept is planned to be implemented in remaining injectors of Mauddud once there are evidences of bad water re-circulation in multiple wells associated with these injectors. Water flood & production efficiency using cyclic water injection approach is a proven way to manage undesirable water encroachment in producers in Sabiriyah Mauddud, the results of which are interesting & worth sharing with the global professionals.