摘要:
A steam cracking process and facility is described which comprises injection of erosive powder to effect at least partial decoking of transfer line exchangers without interrupting the steam cracking stream. The powder, preferably injected just upstream of the transfer line exchangers (TLE) (4), is separated from the cracked gases in primary gas/solid separators (5), temporarily stored in receiving drums at a controlled temperature and evacuated to a common powder storage and/or treatment module by pneumatic transfer by means of a relatively low flow of uncondensable gas. The process and facility can be used to collect solid fragments generated by injection of chemical compounds which are catalysts for the gasification of coke by steam.
摘要:
A facility and a process for steam cracking include controlled injection of solid particles into a transfer line exchanger (3). The particles are injected via injection lines, numbering between 1 and 8, just upstream of an impact-diffuser (6) comprising solid surfaces disposed on either side of the line for transfer of the cracked gases to the exchanger; this impact-diffuser is located in the inlet cone (2) of the exchanger, is permeable to the gases via a plurality of passages and at least 70% opaque viewed from the transfer line.
摘要:
A flexible steam cracking process for hydrocarbon feeds comprises injection of particles with an average size of between 0.02 mm and 4 mm, at a circulation rate in indirect transfer line exchangers (4) of 20 to 180 m/s, and in a sufficient quantity to limit the increase in temperature at the outlet to the exchangers (4) to a value of less than 100.degree. C. per month, into at least one point upstream of an indirect transfer line exchanger (4), cracking zone (2) remaining in communication with downstream means (6) for the treatment of cooled effluents. At least 70% by weight of the quantity of injected particles is introduced between the outlet to the cracking zone (2) and the tubes of the indirect transfer line exchanger (4). Chemical decoking is carried out in the tubes of the cracking zone at time intervals of less than 4 months by establishing accelerated coke gasification conditions, for example by injecting compounds which catalyse gasification by steam, or by decoking in air and/or steam.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
The device comprises at least one column 1 that is filled with a number of beds A.sub.n, whereby each bed A.sub.i is separated from the next bed A.sub.i+1 by a fluid distributor plate P.sub.i. Each plate is divided into a number of sectors P.sub.10, and P.sub.11, and each sector comprises at least two fluid distribution chambers CH.sub.i and CH.sub.j. Each chamber of the plate is connected to a transfer line LT.sub.i and LT.sub.j to the outside. Transfer line LT.sub.i, which is associated with chambers CH.sub.i of a distributor plate, is connected to transfer line LT.sub.j, which is associated with chambers CH.sub.j of the same plate, via a bypass line L.sub.i,j. The latter comprises means 14, 15, 16, and 17 for controlling and adjusting the flow rate of fluid that circulates there, such that each distribution chamber CH.sub.i is flushed by a fluid that is obtained from chamber CH.sub.j and that has approximately the same composition as that of the fluid that circulates through distributor plate P.sub.i at each of the chambers.
摘要:
Apparatus and continuous process for converting hydrocarbons in the presence of a granular catalyst including a metal from group VI a, VII a or VIII, deposited on a carrier, comprising passing a charge of hydrocarbons with hydrogen through a series of at least two vertical catalytic zones in which the catalyst bed moves progressively downwardly, withdrawing progressively the catalyst from the bottom of the last catalytic zone, and reintroducing the same, after regeneration, at the top of the first catalytic zone.
摘要:
The invention relates to an apparatus for carrying out chemical reactions in the presence of at least one catalyst, in at least one reaction zone equipped with heat exchanger plates allowing the temperature of the zone to be controlled. The apparatus mainly comprises a reactor (1), at least one central distributing manifold (6.1a), a plurality of distributing manifolds (6.2a), at least one central receiving manifold (6.5a), a plurality of receiving manifolds (6.4a), a plurality of connecting manifolds (6.6a) and a plurality of hollow, continuous, elongate plates (6.3a), each divided into two hollow half panels (6.3, 1a and 6.3, 2a). The plates are preferably substantially parallelepipedic and may contain adjacent channels having one of the following forms: square, rectangular, triangular, or sinusoidal.
摘要:
Catalytic process for reforming or production of aromatic hydrocarbons at a temperature from 480.degree. to 600.degree. C., wherein a charge of hydrocarbons and hydrogen is passed through two reaction zones, of the moving bed type, whose catalyst continuously flows downwardly and is withdrawn at the bottom thereof, is regenerated, treated with hydrogen and then with a sulfur compound, at respective temperatures lower than the reaction temperature, and thereafter fed back continuously to the reaction zone.