Ebullated bed

Ebullated bed units, unlike any other hydrotreaters, use a fluidized bed of hydroprocessing catalyst with continuous addition and removal of catalyst to maintain system activity. Unlike fixed bed resid catalyst systems, which can use many different catalysts to accomplish specific objectives, ebullated bed units typically use only one catalyst per reactor. That single catalyst must balance the unit requirements for demetallation, desulfurization and conversion.

Control of sediment formation is the biggest issue in most ebullated bed resid units. When the unit is operated for high conversion sediment formation increases, which causes problems in downstream equipment and eventual shutdown for cleaning. Albemarle has developed catalysts specifically designed to achieve high conversion activity while controlling sediment at a level which ensure long operating cycles.