Modelling of heat recovery from suspended oil wells

Abstract

A geothermal system for suspended oil wells is designed to produce 1.25MW of heat. After a review of literature, a concentric double pipe heat exchanger was the system chosen. A control volume model was created to calculate the heat transfer characteristics of the system. After completing the model a suspended oil well near Hinton, Alberta was selected as a candidate well for a geothermal system. The well contains 33 perforated sections which need to be closed off. Three designs to accomplish this are proposed. The model predicted that the best design uses cement squeezes to close off the perforations and produces a net energy of 2.4MW at its optimum operating condition, with a mass flow rate of 8.18kg/s. When producing 1.25MW of heat, the design has a net energy of 1.2MW. It is found that internal heat generation plays a large roll in these systems.