Support assembly for regenerator air distributor in a fluid catalytic cracking unit

A support assembly for the air distributor in the catalyst regenerator vessel of a fluid catalytic cracking apparatus is revealed. The support assembly comprises a primary support which fixedly connects the air distributor to the catalyst regenerator and a plurality of secondary rigid supports. The secondary rigid supports connect to both the air distributor and catalyst regenerator vessel with ball and socket joints. The support assembly allows for unrestricted multi directional thermal expansion of the air distributor without causing twisting or warping.

BACKGROUND OF THE INVENTION 
In the catalyst regenerator of a fluid catalytic cracking unit there is 
typically positioned one or more pipe headers fitted with a plurality of 
nozzles for distributing regeneration gas into the bed of spent catalyst. 
These pipe headers are frequently but not necessarily shaped in a ring 
configuration and supplied by a regeneration gas supply header entering 
the vessel from below as illustrated in U.S. Pat. Nos. 3,912,460 and 
4,443,551 both incorporated herein by reference. 
These pipe headers called air distributors are supported in the vessel and 
since the distributor temperature is high, approaching the process 
temperature (1100.degree. to 1400.degree. F.), and the shell temperatures 
are low (200.degree. to 400.degree. F.); protected by insulation, the air 
distributor support assembly must be able to compensate for considerable 
thermal expansion between the air distributor apparatus, air supply 
header, vessel supporting structure and supporting elements. 
The air distributor support assembly shown in U.S. Pat. No. 4,101,288; 
incorporated herein by reference, solved a number of problems associated 
with thermal expansion experienced in air distributors. This was 
accomplished, as shown in FIG. 1 of the patent by alignment of pivotally 
mounted support members to allow for movement and recovery from 
differential thermal expansion. The direction of thermal expansion induced 
motion must be predicted when using this assembly to achieve the best 
alignment of this apparatus. The present invention is an improvement in 
that it renders such alignment unnecessary, and still compensates for air 
distributor expansion, warping and twisting. 
BRIEF SUMMARY OF THE INVENTION 
The invention is an improvement in the regeneration gas distributor support 
assembly in a catalyst regenerator vessel of a fluid catalytic cracking 
apparatus. 
A first support means fixedly connects the regeneration gas distributor to 
the regenerator vessel. The regeneration gas distributor is supported by, 
along with the first support means, a plurality of rigid supports. The 
rigid supports are adapted to be connected between the regeneration gas 
distributor and the catalyst regenerator vessel. The lower end of the 
rigid support is connected to the catalyst regenerator vessel by means of 
a first ball and socket joint. The upper end of the rigid support is 
connected to the air distributor by means of a second ball and socket 
joint. 
The support assembly provides the regeneration gas distributor with 
multi-directional support and is not so subject to regeneration gas 
distributor twisting or buckling caused by non uniform or restricted 
thermal expansion. The support assembly allows unrestricted horizontal 
growth of the air distributor assembly.

DETAILED DESCRIPTION OF THE DRAWINGS 
While various support devices may be formed by the invention, FIGS. 1-3 
illustrate at least one support assembly that may be formed as described 
herein. 
FIG. 1, a plan view of the regeneration gas distributor 10, is a schematic 
view of the positioning of the support assembly relative to the 
regeneration gas distributor 10. This support assembly comprises first 
support 12, such as the air supply header and four secondary elongated 
rigid supports 13a, 13b, 13c and 13d. 
FIG. 2 is a schematic side view of one of the secondary elongated rigid 
supports 13a of the total support assembly and FIG. 3 is a sectional view 
taken at 3--3 on FIG. 2. The support assembly supports regeneration gas 
distributor 10 on the bottom of a catalyst regenerator vessel 21, in a 
fluid catalytic cracking (FCC) apparatus. Secondary support 13a comprises 
rigid support member 20 comprising an upper end 20u and a lower end 20l. 
Lower end 20l of rigid support member 20 is connected to a lower ball 22l 
seated in lower socket 23l. Upper end 20u is connected to an upper ball 
22u seated in upper socket 22u. Each ball and socket comprises a ball and 
socket joint. The lower end 20l is connected to lower ball 22l in this 
case by means of threads 25, but the ball may be connected by any means 
such as welding, slip fitting, integrally forming, etc. Threads 25 are 
preferred because they allow for easy leveling of regeneration gas 
distributor 10 for the best distribution of regeneration gas in the 
catalyst bed (not shown) of the fluid catalytic cracking (FCC) regenerator 
vessel 21. 
Assembly is effected by filling the socket 23 with fiber insulating 
material 24 and then inserting the ball 22 and rigid support member 20. 
Fiber insulating material 24; for example asbetos or glass wool, packed 
into the joint, seals the area from catalyst intrusion while allowing 
movement in the joint. Final assembly of the socket is made with welds 
23w. Fiber insulation material 24 is held in place by means of brackets 27 
and braided wire hose 28 which seals the area from catalyst while allowing 
movement of the joint. The braided wire hose 28 will compress and expand 
without permanent deformation. 
An upper sleeve 29 is secured, as by welding to a pad 30a, which sleeve is 
also welded to the regeneration gas distributor 10 at the desired point of 
support. Directly below, a similar lower sleeve 31 is secured to pad 32 
which is secured, as by welding to the internal bottom surface of the 
catalyst regenerator vessel 21. Insulating refractory 42 is installed in 
the vacant space inside the lower enlarged sleeve. A vent hole 35 is 
formed in the upper pad 30 and vent holes 36 and 37 are formed in the 
lower pad 32 for escape of air between the pads and their contiguous 
structure to which the pads are welded. 
The principles, preferred embodiments and modes of operation of the present 
invention have been described in the foregoing specification. However, the 
invention which is intended to be protected is not to be construed as 
limited to the particular embodiments disclosed. The embodiments are to be 
regarded as illustrative rather than restrictive. Variations and changes 
may be made by others without departing from the spirit of the present 
invention. For example, variously shaped regeneration gas distributors are 
envisioned. Accordingly, it is expressly intended that all such variations 
and changes which fall within the spirit and scope of the present 
invention as defined in the following claims be embraced thereby.