Experimental and Pilot Investigation of The Impact of Drag Reducing Agents on Filter Performance

Abstract

Drag reducing agents (DRA) are commonly used chemicals in the process and pipeline industry. The unique properties of DRA allow for the reduction in friction and turbulence at the pipe wall, which reduces pumping and transportation costs for both raw crude and refined products. Most of the DRA that is injected into product pipelines is assumed to be sheared into small molecules via turbulence induced polymer chain scission by the time it reaches its destination which eventually renders it ineffective for drag reduction. Although this may sometimes be the case, often unsheared or partially sheared DRA persists in hydrocarbon products which may cause problems for end-users. DRA has been cited as the culprit for issues with clogging of fuel injectors and fuel filters. Problems of this nature have been reported by end-users of diesel and aviation fuel products. As a result, it is often in the best interest of refiners and fuel wholesalers to ensure that their products have minimal to no persisting DRA contamination prior to sale. Filtration is one viable method of lowering the DRA concentrations in fuel products, however the impacts of macro-molecular DRA on filter life and performance is not well understood. To this end, a study was conducted to investigate the impact of hydrocarbon-based DRA on the filtration systems. A method to characterize the level of DRA contamination in product fuel, the polymer filtration index (PFI), is presented and utilized to benchmark the performance of a media filter. Impacts of DRA on filter life and removal efficiency are discussed from an industrial perspective. In light of the findings, a discussion on filtration as a method for the removal of DRA from diesel fuels is presented.