Patent ID: 8398846
Filing Date: 2013-03-19
Classification: C10G

Abstract:
1. A process for thermally cracking a hydrocarbon feed in an installation comprising a radiant section, a convection section and a feed preheater pick-up controller, the process comprising: feeding a hydrocarbon feed stock to a feed preheater present in the convection section so as to produce heated feed, wherein the feed preheater as a heat pick-up is imparting heat to the hydrocarbon feed; separating the heated feed in a separator into a vaporous fraction and a liquid fraction; controlling the heat pick-up of the feed preheater by regulating a boiler feed water heat exchange medium flow in a heat economizer and a top economiser, wherein the heat economizer is positioned in the convection section between the feed preheater and the radiant section and the top economiser is positioned in the convection section between a flue gas exit of the convection section and the feed preheater; and thereafter cracking at least part of the vaporous fraction in the radiant section, wherein the feed preheater pick-up controller comprises: an input for registering liquid flow of the liquid fraction leaving the separator and/or an input for registering a temperature of the vaporous fraction leaving the separator, and an output for regulating, based on the input registered, a rate of the flow of the heat exchange medium in the heat economiser and a rate of the flow in the top economiser.