Reservoir Management of Brown Field: Kalol, A Case Study

Abstract

Abstract Kalol is a multi-layered field comprising of nine pay zones. Pay zones II, III and IV are both oil and gas bearing while pay zones V, VI + VII, IX + X, XI and XII are oil reservoirs. The field has in-place (PD) reserves of 131.84 MMt of oil with an ultimate (PDD) component of 18.23 MMt as on 1.4.2009 respectively. The cumulative production as on 1.4.2008 is 12.77 MMt of oil leading to a recovery of 9.7%.As on 1.4.2008 a total of 610 wells are drilled of which 385 wells are completed as oil wells with 329 flowing & 56 non-flowing wells, 23 as flowing gas wells and 80 as water injection wells. Out of total flowing oil wells 91 % are operating on artificial lift with 140 wells on SRP and 159 wells on gas lift. The average rate of production during the year was 1140 tpd of oil and 259000m3/d of gas. The oil production was maintained mainly by development drilling, zone transfers, lift management and faster revival of ceased wells. Water injection is being carried out in pay zones K-III, V, VI+VII, IX+X and XII through 68 wells @2600 m3/d. Due emphasis was given for pressure maintenance schemes to meet instantaneous void age compensation through proper redistribution and focused water injection. Induction of various technologies are been attempted to maintain the oil production rate from this Brown field, major among them are drilling of Horizontal, Multi-lateral and high angle wells, MEOR technologies, application of PDB technology, Hydro-fracturing, Stimulations of tight sand stone-layer, enhancing the quantity and quality of water injection for effective pressure maintenance and improving the recovery factor. Various surface and sub-surface interventions through multi-disciplinary team approach have paid rich dividend and production of the field have enhanced through these initiatives. Paper will discuss the innovative approaches conceptualize and implemented in the field for maintaining and enhancing the production level and improving the reservoir health.