Optimized Workflows to Assist in Managing the Sour Gases & Oil Production in North Kuwait Jurassic Fields

Abstract

The complex Jurassic fields consist of eight onshore fractured carbonate fields, producing from four different structures. In the reservoir, fluids are in critical phase. Three out of the eight reservoirs are volatile oil and the remaining are Gas-condensates with high H2S & CO2. Currently ~35 wells are connected to the Early Production Facility (EPF) and the well deliverability is just enough to produce at the facility design capacity. As per the development strategy more wells will be connected to the facility for Long term tests (LTT) and booking reserves. As per the current development plan, additional processing facilities will be commissioned in next 2 years. Over seventy additional wells will be connected to these facilities with the target to triple production. In order to achieve the targets of the Jurassic field development plan, a flagship DOF (Digital Oil Filed) program called KwIDF (Kuwait Integrated Digital Field) was deployed by instrumenting ~35 wells and developing 22 production surveillance and analytics workflows. These workflows encompass HSE, operations and engineering requirements of the asset. Phase-1 of this technology program was initiated in 2010 and deemed complete in mid-2012. Since then the maintenance and enhancements of the existing system was done by improving the workflows which assist in better management, decision making, field monitoring and operations. This paper describes the new workflows which were built over the last 3 years where automated calculations run every hour to estimate flow rates for Oil, Gas, Water, H2S & CO2 based on combining real time well data and steady state nodal analysis models. The blended API workflow tracks the crude API density at the outlet of the Early Production Facility (EPF) and helps to prioritize wells to be connected to meet the target crude density. Similarly the H2S & CO2 monitoring workflows calculate the daily average H2S & CO2 rates and its percentage. These workflows along with the choke sensitivity workflow helps to optimize the production with the H2S & CO2 constraints. With the expansion of the field, a technology upgrade is also being planned under a Jurassic KwIDF Phase-2 program. The technical design of KwIDF Phase-2 was completed on April 2015 and the new workflows to be developed have been identified. The new workflows will focus to improve the well performance monitoring, Virtual Flow Metering (VFM), Surface – Subsurface integration, Choke Management, hydrate control and well & pipeline integrity.