Multi-Scale Modeling of Wax Deposition in Pipelines

Arizona State University, Scottsdale AZ

Investigators

Abstract

0932968 Herrmann Wax deposition inside crude oil pipelines can severely hamper oil recovery, and can lead to curtailment of well production. A fundamental understanding of the mechanisms of wax deposition and aging (hardening) of the deposited matter on the interior pipe surface is essential for the optimal design and implementation of wax removal techniques. This research investigates wax deposition phenomena by employing multi-scale modeling coupled with laboratory experiments. Intellectual Merit: The growth rate and microstructure evolution of the wax deposition layer is predicted through coupled heat transfer, fluid and particle flow, and kinetics modeling at the micro through macro scales. Velocity distributions and heat transfer within the bulk liquid and porous wax deposition are described at the macro scale, while the nucleation, growth and precipitation of wax particulates are described at the mesoscale. Modeling of the microstructure evolution within the deposition will provide information on the wax content and thus the aging process of the wax deposit. Companion experiments will be carried out at the China University of Petroleum. The morphology of the deposit layers that are grown in the laboratory will be analyzed using Cross-Polarizing Microscopy and Differential Scanning Calorimetry. The experimental measurements will be used to validate the theoretical model. Broader Impacts: The research will enable the prediction of wax deposition phenomena, and the combined computational and experimental approach may lead to scaling laws that can be applied to field operations. Crude oil production rates might be improved, while energy costs associated with production will be decreased. The project will include development of a multimedia web site designed for students and researchers to promote better understanding of crude oil wax deposition phenomena. Students will gain valuable experience in global collaboration. Students from underrepresented groups will be engaged by utilizing existing infrastructure at Arizona State including the Women in Science and Engineering Program, the Fulton Undergraduate Research Initiative, and the NSF-sponsored Western Alliance to Expand Student Opportunities as well as the Minority Graduate Education Mountain States Alliance.