This Topical Report on Shale Oil Dedusting''presents the results of a research program conducted by the Illinois Institute of Technology (IIT, Chicago) to determine the suitability and effectiveness of the lamella electrosettler -- a novel solid-liquid separation device -- for removing fine shale particles from shale oil via the application of an electric field. The work was conducted by IIT from November 1989 through December 1990 as a subcontractor to the Institute of Gas Technology. The overall objective of the larger program was to develop the Pressurized Fluidized-Bed Hydroretorting (PFH) Process for EasternOil Shales.''The subtask undertaken by IIT was part of a larger task entitled Testing of Process Improvement Concepts.''The lamella electrosettler has been shown to be an effective method for separating fine particulate (including colloidal) matter from a liquid using the application of an electric field. Using the walls of the settler as electrodes and during continuous operation, solids migrate preferentially toward one of the electrodes and become concentrated in the refuse stream. The product stream is clarified of particulates. The success of the process depends upon the physical properties of the solids and liquids being tested. A sample with a high specific conductance is not suitable for separation in the lamella electrosettler. The liquid begins to heat up under the influence of the electric field and, eventually, may short. Also, under these conditions, the particles cannot maintain a charge. The high conductivity of the shale oil samples tested rendered them unsuitable for further testing in the lamella electrosettler.