This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 196217, “Assessment of Government Incentives and Development Strategies To Revitalize Mature Heavy-Oil Fields in the Peruvian Jungle,” by Nosser A. Jurado, SPE, National Bank Financial, and Victor A. Huerta, SPE, Universidad Nacional de IngenerÍa, prepared for the 2019 SPE Annual Technical Conference and Exhibition, Calgary, 30 September–2 October. The paper has not been peer reviewed. Mature heavy-oil fields in the northern Peruvian jungle have produced oil for more than 40 years under primary recovery mechanisms (cold methods). The complete paper explores technical and economic development options to produce heavy-oil resources at commercial rates and showcases three optimization scenarios of higher recovery efficiency aimed at increasing net present value at the basin level. Introduction The constant decline of medium- and light-oil production in most Peruvian fields in recent years, along with the increase in domestic demand, indicates that innovative redevelopment strategies should be implemented for recent large heavy-oil discoveries in the Marañon Basin. The Norperuano pipeline in its current condition and egress capacity allows exploitation of proved developed producing volumes of Blocks 64, 192, 8, and 95 but constrains the commerciality and development possibilities for Block 67 (Piraña, Dorado, and Paiche fields) and Block 64 (Situche field), which jointly could pro-duce up to 70,000 B/D between 2027 and 2029. The main issue is the present constraint for transportation and blending of heavy oil and diluents. Therefore, an infrastructure revamp is necessary. The authors believe that capital expenditure (CAPEX) to carry out these improvements and expansions is necessary and must be addressed between the operators in the area and the Peruvian government while considering all social and current environmental issues. Analysis of Production Performance and Recovery Most Peruvian heavy-oil fields have been discovered in the Marañon Basin. Production history indicates a strong water-drive mechanism by which oil production declines as water rate increases, while reservoir pressure is sustained with a less than 20% pressure decrease. Generally speaking, Marañon wells have been drilled following slant trajectories and are only completed with slotted liners without a selective completion. Consequently, no method exists to isolate water zones or encroachment, and oil productivity and relative permeability to oil decrease rapidly as water cut increases. Horizontal wells have been proposed for the Bretaña heavy-oil field in Block 95. This field is similar to the Jibaro and Jibarito fields in Block 192, with completions featuring autonomous inflow-control devices (AICDs) to delay water breakthrough while improving production performance and increasing oil recovery. Another alternative suggested to increase recovery factor and prevent water breakthrough is dual completion with electrical submersible pumps (ESPs). This completion type has been envisioned for Block 192. On a well-by-well basis, increasing the recovery factor by implementing new technologies is possible. On a transportation-and-gathering basis, however, issues remain in the basin. A production deferment of at least 7% has been the result of several factors, including a lack of appropriate well-service programs to replace ESPs and clean boreholes, inadequate infrastructure, deteriorating roads accessing the fields, the lack of a supply-change-management program, and a lack of appropriate management of social and environmental issues. CAPEX allocations to the Norperuano pipeline would minimize this problem at the basin level and might solve delay issues at the field level for all blocks.
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