As much as six years can elapse from completing the configuration study to the unit starting up and much can change in that time. Market conditions may have shifted or there may have been changes in emissions legislation or product-quality specifications. For example, if the market demand for middle distillates has outstripped the initial forecasts, the owner may be keen to increase capacity or, if some product streams are achieving an unanticipated margin, modify for a different product slate.
Shell Global Solutions has worked with several refiners, including, for example, Valero and Marathon, to revamp their newly started up hydrocrackers. These projects made relatively small adjustments but their impacts were substantial: they ensured that the new assets continue to be relevant to the prevailing market conditions and provide substantial bottom line benefits.