Abstract: A steam-cracking unit comprises at least one multitube quenching exchanger, equipped with a non-obstructive impact separator for preventing the erosion of the tubular input plate. The impact separator is at least 50% opaque when viewed from transfer pipe. It is arranged inside of an input cone in such a way that there is free passage of at least 40 mm between the periphery of the impact separator and the cone.

Abstract: A steam-cracking process includes the injection, at at least one point upstream from a secondary quenching indirect exchanger (4b), of particles with a mean size of between 0.02 and 4 mm, at a velocity speed in the exchanger of 20 to 180 m/s, in sufficient quantity to limit the rise in the output temperature of the effluents from the exchanger to a value that is less than 100° C. per month. At least 70% by weight of the quantity of injected particles is introduced downstream from primary quenching exchangers (4a) and upstream from the inlet to the secondary quenching exchanger. At intervals, decoking of the pyrolysis pipes and primary quenching exchangers is carried out in the presence of air.

Abstract: A steam-cracking unit and a steam-cracking process with controlled injection of solid particles in a quenching exchanger (3) is described. The particles are injected through a single axial injection pipe that is arranged on the axis of input cone (2) of the quenching exchanger, just upstream from an impact separator-diffuser (6) that comprises solid surfaces that are arranged opposite the transfer pipe of the cracked gases toward the exchanger; this impact separator-distributor is located in input cone (2) of the exchanger and is gas-permeable along a number of passages and at least 70% opaque when viewed from the transfer pipe.

Abstract: A process is described for catalytic cracking of a petroleum feed in which a catalyst from a regeneration zone 4 is caused to flow in a dense fluidized bed conditioning zone 2 upstream of an injection zone 10, the fluidization rate being 0.1 to 30 cm/s. The throughput of catalyst into injection zone 10 is regulated by a constriction means 11. The hydrocarbon feed 12 is injected below the constriction means and flows counter-current to the direction of flow of the shaped catalyst flow. The hydrocarbon feed 12 is injected at a set injection angle depending on the movement of the feed and the catalyst.

Abstract: The hydrotreatment of hydrocarbons in the liquid phase is effected in a column containing a catalyst bed supported by a grid, wherethrough passes an ascending stream of the charge admixed with hydrogen which expands the catalyst bed, the perforations of the grid being small enough to prevent passage of the catalyst particles but large enough to permit passage of the hydrogen-charge mixture, the reaction effluent being withdrawn from the top of the column. The reactor column is provided with means between the hydrogen-charge mixture introducing means and the catalyst bed supporting grid for mixing and dispersing the combined liquid-gas charge.

Abstract: The hydrotreatment of hydrocarbons in the liquid phase is effected in a column containing a catalyst fixed or moving bed supported by a grid, wherethrough passes an ascending stream of the charge admixed with hydrogen. The perforations of the grid are small enough to prevent passage of the catalyst particles but large enough for giving passage to the hydrogen-charge mixture. The reaction effluent is withdrawn from the top of the column.

Abstract: The hydrotreatment of hydrocarbons in the liquid phase is effected in a column containing a catalyst bed supported by a grid, wherethrough passes an ascending stream of the charge admixed with hydrogen which expands the catalyst bed, the perforations of the grid being small enough to prevent passage of the catalyst particles but large enough to permit passage of the hydrogen-charge mixture, the reaction effluent being withdrawn from the top of the column.