Maximizing recovery from strong water drive, permeable reservoirs in North Kuwait usually require a combination of approaches. Implementing partial perforating techniques across the oil column above the oil/water contact and installing tubing sizes that secure maximum natural flow life cycle are presently utilized to extend the natural flow life cycle in strong bottom- and edge-water drive reservoirs. Limiting production rate at or below critical coning rate, and conversion to Artificial Lift when the water cut increase forces cessation of natural flow, further improve the ultimate recovery of oil from these reservoirs. In pilot Well-A, approximately 55% of the oil column above the Oil/Water contact was perforated on initial completion. Within 6 months from initial completion, the Watercut increased from 0% to 53%, then gradually increased to 74% over the next four years of natural flow life. Before the natural flow ceased completely, the well was worked over to install the innovative Downhole Water Sink completion. This completion design comprised of a very short perforated interval at the original depth of the Oil/Water contact and with another perforated interval across a highly permeable aquifer below the layer of interest. A shrouded ESP with Y-tool assembly was then installed, able to generate a drawdown just below the original OWC that is greater than the drawdown across the originally perforated interval. This pressure sink created at the OWC controls the further development of the water cone around the wellbore thereby increasing the maximum coning rate, in addition to accelerating and increasing the ultimate recovery from this water-drive completion. The excessive water that is usually produced to surface, and processed along with the oil, is now significantly reduced since most of it is now re-directed to a deeper non-oil-producing aquifer. Though the watercut is never eliminated at the oil perforations, the natural flow life cycle is extended, and thereby the ultimate recovery considerably improved. Actual % improvement is yet to be determined since the watercut of the produced fluid at surface has not yet risen to the level that causes cessation of natural flow. This pilot application of the Downhole Water Sink technology to this North Kuwait water-drive reservoir opened up immense opportunities for comparable recovery improvements in similar and even larger water-drive reservoirs in other Assets within the company. Where reservoir pressures are insufficient to maintain natural flow, a dual ESP system is already designed to lift the oil column using the same Downhole Water Sink principle.

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In a high-perm/strong-aquifer environment, comparatively low-perm/heavy-oil/solution-gas-drive reservoirs inevitably get sidelined. Flow-Channel Hydraulic Fracturing, however, with infinite conductive channels for fluid flow rather than intra-granular flow, as in conventional fracturing techniques, offers a tangible solution for increased productivity. The channels in the proppant pack are created through a patented technique that combines special pumping protocol, perforation scheme, fracturing fluid design and fiber technology. These conductive channels accelerate fracture cleanup, and achieve longer effective fracture half-lengths, thereby enhancing productivity, injectivity& recovery. In North Kuwait, 90% of wells drilled are vertical, penetrating a wide range of reservoir types consisting of high and low permeability sandstones and carbonates, with varying crude types from medium heavy to condensate. Flow-Channel Hydraulic Fracturing technology, with its infinite conductive flow-channels and reduced risk of premature screen-outs, was selected as the optimum stimulation technology for the most challenging low-permeability/low API gravity candidates where conventional stimulation techniques are not providing the aimed results. Conventional propped hydro-frac treatments were attempted previously with marginal benefit and operational failures. This was the first application of this technology in Kuwait. Multi-disciplinary candidate screening and selection for the initial pilot wells, followed by pre-job logistics and operational planning with the service provider, resulted in a flawless execution with text-book results. Post-job production results showed a stabilized flow rates with more than 85% production gain compared to the flow rates expected from conventional completion techniques. Incremental production paid out stimulation expenses in 35 days. This very successful introduction for Flow-Channel Fracturing application opened up opportunities in low API reservoirs where even the flow through the proppant pack from conventional fracture stimulations is limited. Injectors associated with IOR & EOR projects, and Carbonate completions traditionally responding to repeated periodic acid fracture stimulation, may require only single channel proppant fracture during their life cycle.

Water Shut-Off (WSO) solutions are in constant improvement. This paper shares the experience of integrating PLT, CTU, and packer Real-time technologies together in multidisciplinary team and integrated workflows to minimize the uncertainty and maximize the success rate of Rig-less WSO in horizontal open-hole wells completed with passive Inflow Control Devices (ICD) as first time ever in Kuwait, to extend the natural flow life which in turn reduces oil production deferment waiting for slot in busy rig work-over schedule.Water conformance represents common challenge in oilfield industry which increases with the field maturity especially in water flood and active water drive reservoirs. Water production has significant impact on production economics, facilities, adding more challenges to the development of such oilfields.Sabriyah field, most challenging oilfield in North Kuwait, produces from Lower Burgan (LB) Cretaceous Sandstone reservoir which experiences water conformance issues due to water flood and active water drive respectively.Strategy of drilling horizontal open-hole wells completed with passive ICDs in LB reservoir was adapted early 2012 as trial to delay water breakthrough via achieving higher productivity over conventional vertical wells and in turn be able to produce same average production rate at much less and balanced drawdown. However, some wells have shown increased water cut (WC), which constrained their natural flow capability and hence need for rig work-over for WSO and/or conversion to artificial lift.WSO is a common practice in the field but complicity increases in horizontal completions. The main challenge during WSO treatment is the proper diagnosis and full understanding of the water mechanism for selecting the efficient treatment design, which is crucial for a sound decision making considering the associated cost and the operational complications especially in horizontal wells.Process outline: WC monitoring, identification of water source using horizontal PLT, Water Saturation logs, reservoir understanding, production modeling and nodal analysis, identifying best WSO intervention technology, isolation depth and operation design then execution and post job evaluation.The production analysis utilizing horizontal PLT technology, Water Saturation and open-hole logs supports inflow profiling and identification of water entries in horizontal ICD compartments. Hence, better problem understanding and proper decision making for where to isolate using Rig-less Real-time CTU and inflatable packer technology in three wells to-date with following results:• Significant oil gain/restore and WC reduction. • Extending natural flow life and postpone need for rig work-over. • Less water on facility side allowing more production capacity.• Saving reservoir energy.The integration of inflow profiling, water saturation, Real-time intervention new technologies and multidisciplinary team collaboration led to excellent execution of rig-less WSO in horizontal passive ICD completions in North Kuwait.

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