Investigation of agglomeration in fluid coking

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The proposed research addresses agglomerate formation in fluid coking used to process bitumen from Canadian oil sands. Bitumen is sprayed into the reactor through a large number of nozzles that use steam to assist atomization. The liquid reacts on the surface of hot coke particles resulting in distillate products, gases, and coke. The efficiency of the process depends on many parameters with film coating of the coke particle and the interaction between particles playing an important role. When bitumen is injected, it acts as a liquid binder and forms agglomerates. Some of those break up while others survive, leading to stable agglomerates that are damaging because they cause lower desirable product yield and fouling of the reactor internals. It can also cause defluidization. Therefore understanding the process that leads to reducing agglomerate formation is critical for process efficiency. The objective of this research is to develop comprehensive mathematical models to represent the aggregate formation and breaking. It will use computational fluid dynamics with population balance methods to represent the multiphase flow of multiple solid, liquid, and gaseous phases. It will use Eulerlian/Eulerian representation of the phases in the reactor and Discrete Element Methods (DEM) to develop the correlations needed for the representation of phenomena and the particle level. The industrial partner, Syncrude, uses fluid coking to upgrade the bitumen to valuable products. It operates three of the world's largest fluid coking process units producing about 350 000 barrels of synthetic crude per day. These fluid coking process units, together with Imperial Oil's fluid coking process unit in Sarnia, process between 15 and 20% of Canada's crude oil production. Syncrude's operation is located in Fort McMurray, Alberta, Canada, and employs approximately 5200 people. A 1% increase in liquid volume yields corresponds to a prize of approximately $50 million per year. Because of the increased efficiency, less bitumen would be needed resulting in less environmental impact. The oil sands are very important to the Canadian economy because of the significant contribution to the GDP and the large number of jobs created.