Production Optimization Through Intelligent Multilateral Wells in Heavy Oil Fields via Electrical Heating

Abstract

Electrical resistance heating provides key advantages over other thermal recovery methods in the recovery of heavy oil resources. These advantages include low upfront capital expenses, more control on the delivery of the heat spatially, easiness of permitting in environmentally sensitive areas as well as environmental and economic benefits due to lower carbon footprint. However, the recovery efficiency is relatively lower compared to more conventional methods such as CSS, steamflood and SAGD processes as it doesn't introduce a (pressure) drive mechanism and radius of impact is relatively small which may result in marginal economics.1 In this study, the application of electrical resistance heating on multilateral wells are studied in order to illustrate the enhanced physical and economic benefits of the method with the multilaterals.2 A comprehensive review of the technology with all the technical and economic details on the deployment of the electrical resistance heater is provided. A full-physics commercial reservoir simulator is utilized to model a benchmark model and it is coupled with a robust optimization and uncertainty tool to investigate the significance of the control and uncertainty variables in the system. Propagation of the heat, increased the radius of impact, production performance, energy input and economics are outlined in comparison to the base case where the horizontal well is modeled without the extra laterals. Production engineering and deployment aspects are all provided in detail, as well. Utilization of electrical resistance heaters on multilateral wells provides improved economics due to the increased recovery with the additional accessible reservoir volume for heating with the reduced cost of the additional laterals as opposed to the major cost of the main wellbore. The improved unit cost for the heater per foot also helps the economics, thus increased the radius of impact translates into better recovery at lower unit costs. Model inputs as well as the results including the production performances, significance of key parameters and economics, are outlined in a comparative manner. Electrical resistance heating is not a new process but has recently gained more attention due to the advances in the materials used providing better durability, however, the recovery process needs special designs that bring down the unit cost to make the projects feasible. This study provides a new approach in improving recovery in electrical resistance heating methods that may help to turn several potential marginal projects into projects with more favorable economics in a method which has a great potential in an industry becoming more environmentally sensitive.