Process model correlating Athabasca bitumen thermally cracked at edge of coking induction zone

Abstract

Athabasca bitumen is an abundant resource that has successfully been upgraded using delayed coking that typically operates at 499 °C (∼930 °F), 207 kPa (∼37 psig), 1–2 min residence time on this type of crude. With society’s desire to reduce industry environmental impact while still providing energy to earth’s growing population, lower energy intensive (and thus lower greenhouse gas emissions) bitumen conversion approaches have been researched and are moving towards commercialization. The paper reviews a correlative model developed on a novel thermal cracking process, operated at lower temperatures (395–405 °C (743–761 °F)), lower pressures (<69 kPa (∼<10 psig) and up to 1 h residence time versus delayed coking, that takes various lab and pilot data, both batch and continuous, as inputs into developing the model. The purpose of the model is for use in industrial operations to provide guidance to operations for representative thermal cracker performance. The model is based on the Arrhenius equation using first order reaction kinetics for easy comprehension and use in an operational environment. Data for developing the model has been taken from various literature sources in the area of study, notably by researchers, Dr. W. Svrcek, Dr. Wiehe, Dr. Mehrotra, and Dr. Yarranton. The public data is used to create a viable range of performance that includes proprietary developments with the novel thermal cracking process. The model is configured on a mass basis so that mass balance closure can be readily calculated. A range of kinetic coefficients are provided that can be used to fit commercial plant performance based on the expected range of product outputs noted in the paper.