Abstract: A cooling system that includes a heat exchange plate defining a coolant circulation duct and equipped with connector elements each having a closure member for opening and closing the connector elements to the coolant circulation duct, a volume compensating device including a piston mounted to slide, relative to the plate, between a first retracted position and a second forward position, and wherein the system includes a coolant supply for the duct and a coolant discharge for the duct each of which includes connecting elements complementary to the connector elements of the plate, and wherein a maintaining member is secured to at least a first complementary connector element to lock the piston in the first position, when a first connector element of the plate and the first complementary connecting element are coupled, and retains the piston in the first position, during separation of the first connector element of the plate and the first complementary connecting element and until the closure member of the first

Abstract: This invention relates to a process and an installation for treatment of a heavy petroleum feedstock, of which at least 80% by weight has a boiling point of greater than 340° C., whereby the process comprises the following stages: (a) Hydroconversion in a fixed-bed reactor operating with an upward flow of liquid and gas, whereby the net conversion in products boiling below 360° C.