Air pollution is a topic currently studied to address the well-known health problems that can arise from it. The use of an ESP (electrostatic precipitator) for treatment with submicron particles from sources such as small-scale combustion systems presents some advantages in comparison to other possible devices. In this study, a new ESP prototype geometry based on separating the discharge electrode support from the gas stream path was designed, constructed and tested. The gas stream from a small-size diesel internal combustion engine was used. Good ESP behavior over moderate time periods was verified by achieving average collection efficiencies of 97 +/- 4%. TG (Thermogravimetric) and SEM-EDS (Scanning Electron Microscopy with Energy Dispersive X-Ray Spectroscopy) analyses were performed. The influence of the regulation power value and the discharge electrode effective length on the collection efficiency was evaluated. Higher removal efficiencies were linked to higher power values and higher discharge electrode effective lengths. A high impact of the operating time was observed. Different discharge electrode geometries were tested, indicating an increase in collection efficiency as the power increased for stainless steel electrodes and the opposite trend for M12 threaded rod electrodes. (C) 2016 Elsevier Ltd. All rights reserved.