Title of Invention

CATALYST WITHDRAWAL APPARATUS FOR REGULATING CATALYST INVENTORY IN A FLUID CATALYST CRACKING UNIT

Abstract A catalyst withdrawal apparatus and method for regulating catalyst inventory in a fluid catalytic cracking catalyst (FCC) unit is provided. In one embodiment, a catalyst withdrawal apparatus for removing catalyst from a FCC unit includes a pressure vessel having a metering device coupled to a fill port. A heat dissipater is located adjacent the metering device and is adapted to cool catalyst entering the pressure vessel. A sensor is coupled to the pressure vessel arranged to provide a metric indicative of catalyst entering the pressure vessel through the metering device. In another embodiment, a method for regulating catalyst inventory in a FCC unit includes the steps of determining a change of catalyst present in a FCC unit, withdrawing catalyst from the FCC unit into an isolatable storage vessel coupled to the FCC unit, measuring the amount of catalyst disposed in the storage vessel, and removing the measured catalyst from the storage vessel.
Full Text Date of Deposit: 14 July 2006 Attorney Docket No. CAT/013PCT
Express Mail Label: EV840619730US
CATALYST WITHDRAWAL APPARATUS AND METHOD
FOR REGULATING CATALYST INVENTORY IN A FLUID
CATALYST CRACKING UNIT
BACKGROUND OF THE INVENTION
Field of the Invention
[0001] Embodiments of the invention generally relate to a catalyst
withdrawal apparatus and method for regulating catalyst inventory in a fluid
catalytic cracking catalyst unit.
Description of the Related Art
[0002] Figure 1 is a simplified schematic of a conventional fluid catalytic
cracking system 130. The fluid catalytic cracking system 130 generally includes
a fluid catalytic cracking (FCC) unit 110 coupled to a catalyst injection system
100, a petroleum feed stock source 104, an exhaust system 114 and a
distillation system 116. One or more catalysts from the catalyst injection
system 100 and petroleum from the petroleum feed stock source 104 are
delivered to the FCC unit 110. The petroleum and catalysts are reacted in the
FCC unit 110 to produce a vapor that is collected and separated into various
petrochemical products in the distillation system 116. The exhaust system 114
is coupled to the FCC unit 110 and is adapted to control and/or monitor the
exhausted byproducts of the fluid cracking process.
[0003] The FCC unit 110 includes a regenerator 150 and a reactor 152.
The reactor 152 primarily houses the catalytic cracking reaction of the
petroleum feed stock and delivers the cracked product in vapor form to the
distillation system 116. Spend catalyst from the cracking reaction is transfer
from the reactor 152 to the regenerator 150 where the catalyst is rejuvenated
by removing coke and other materials. The rejuvenated catalyst is reintroduced
into the reactor 152 to continue the petroleum cracking process. By-products
from the catalyst rejuvenation are exhausted from the regenerator 150 through
an effluent stack of the exhaust system 114.
1

Date of Deposit: 14 July 2006 Attorney Docket No. CAT/013PCT
Express Mail Label: EV840619730US
[0004] The FCC unit 110 includes a catalyst injection system 100 that
maintains a continuous or semi continuous addition of fresh catalyst to the
inventory circulating between the regenerator 150 and the reactor 152. The
catalyst injection system 100 includes a main catalyst source 102 and one or
more additive sources 106. The main catalyst source 102 and the additive
source 106 are coupled to the FCC unit 110 by a process line 122. A fluid
source, such as a blower or air compressor 108, is coupled to the process line
122 and provides pressurized fluid, such as air, that is utilized to carry the
various powdered catalysts from the sources 102, 106 through the process line
122 and into the FCC unit 110.
[0005] One or more controllers 120 is/are utilized to control the amounts of
catalysts and additives utilized in the FCC unit 110. Typically, different
additives are provided to the FCC unit 110 to control the ratio of product types
recovered in the distillation system 116 (i.e., for example, more LPG than
gasoline) and to control the composition of emissions passing through the
exhaust system 114, among other process control attributes. As the controller
120 is generally positioned proximate the catalyst sources 106, 102 and the
FCC unit 110, the controller 120 is typically housed in an explosion-proof
enclosure to prevent spark ignition of gases which may potentially exist on the
exterior of the enclosure in a petroleum processing environment.
[0006] During processing, there is a dynamic balance of the total catalyst
within the FCC unit. As discussed above, catalyst is periodically added utilizing
a catalyst injection system. During the cracking process, some catalyst is lost
through the distillation system 116, while some catalyst is lost through the
effluent exiting the regenerator 150. The addition rate required to maintain a
desired level of catalytic activity sometimes matches the loss rate through
attrition, and in this case, there is no need for corrective measures.
[0007] If the amount of catalyst within the FCC unit diminishes over time,
the performance and desired output of the FCC unit will diminish, and the FCC
unit will become inoperable. Conversely, if the catalyst inventory in the FCC
unit increases over time, the catalyst bed level within the regenerator reaches
an upper operating limit, necessitating a small catalyst withdrawal to prevent
2

Date of Deposit: 14 July 2006 Attorney Docket No. CAT/013PCT
Express Mail Label: EV840619730US
unacceptably high catalyst emissions into the flue gas stream, or other process
upsets.
[0008] Catalyst withdrawal systems are normally sized for the most
demanding operating case, which is when the entire catalyst inventory is
removed during a short period of time when the FCC unit is shut down. The
periodic operational-type catalyst withdrawals for level control addressed by this
invention can take place once a day, once a week, or once a month, depending
on how quickly the catalyst inventory level is building. Because these sudden
changes in regenerator bed level cause changes in the pressure balance of the
FCC unit, they may result in changes in catalyst circulation rate, reactor
temperature and/or regenerator temperature, and these upset the stability of
the FCC unit operation. As these changes in the dynamic equilibrium force the
FCC unit away from its operating limits, the desired product mix and/or effluent
composition may not be obtained. As the FCC unit is a major profit center in
most refineries, a great deal of time and investment made by refineries to
ensure the FCC unit is always operating against its operating limits, thereby
maximizing profitability. Anything that forces the operation of the FCC unit
away from these limits reduces profitability and is a major detriment to the
refiner. Thus, it would be highly desirable to stabilize the FCC operation by
eliminating sudden catalyst withdrawals, thus maintaining the dynamic balance
of catalyst in a FCC unit.
[0009] Therefore, there is a need for a catalyst withdrawal apparatus
suitable for use with a fluid catalytic cracking catalyst unit.
SUMMARY OF THE INVENTION
[0010] A catalyst withdrawal apparatus and method for regulating catalyst
inventory in a fluid catalytic cracking catalyst (FCC) unit is provided. In one
embodiment, a catalyst withdrawal apparatus for removing catalyst from a FCC
unit includes a pressure vessel having a metering device coupled to a fill port.
A heat dissipater is located adjacent the metering device and is adapted to cool
catalyst entering the pressure vessel. A sensor is coupled to the pressure
vessel arranged to provide a metric indicative of catalyst entering the pressure
vessel through the metering device.
3

Date of Deposit: 14 July 2006 Attorney Docket No. CAT/013PCT
Express Mail Label: EV840619730US
[0011] In another embodiment, a fluid catalyst cracking system is provided
that includes a FCC unit having a catalyst withdrawal apparatus coupled thereto
and configured to meter catalyst removed from the FCCU.
[0012] In yet another embodiment, a method for regulating catalyst
inventory in a FCC unit includes the steps of determining a change of catalyst
present in a FCC unit, withdrawing catalyst from the FCC unit into an isolatable
storage vessel coupled to the FCC unit, measuring the amount of catalyst
disposed in the storage vessel, and removing the measured catalyst from the
storage vessel.
DESCRIPTION OF THE DRAWINGS
[0013] So that the manner in which the above recited features of the
present invention are attained and can be understood in detail, a more
particular description of the invention, briefly summarized above, may be had
by reference to the embodiments thereof which are illustrated in the appended
drawings. It is to be noted, however, that the appended drawings illustrate only
typical embodiments of this invention and are therefore not to be considered
limiting of its scope, for the invention may admit to other equally effective
embodiments.
[0014] Figure 1 is a simplified schematic view of a conventional fluid
catalytic cracking system;
[0015] Figure 2 is a simplified schematic diagram of a fluid catalytic
cracking system having a catalyst withdrawal system in accordance with one
embodiment of the present invention;
[0016] Figure 3 is a sectional view of on embodiment of the catalyst
withdrawal system of Figure 2; and
[0017] Figure 4 is a flow diagram of one embodiment of a method of
regulating catalyst in a fluid catalytic cracking system.
[0018] To facilitate understanding, identical reference numerals have been
used, wherever possible, to designate identical elements that are common to
the figures. It is contemplated that features from any one embodiment may be
beneficially incorporated in other embodiments without additional recitation.
4

Date of Deposit: 14 July 2006 Attorney Docket No. CAT/013PCT
Express Mail Label: EV840619730US
DETAILED DESCRIPTION
[0019] The invention generally provides catalyst withdrawal apparatus
suitable for use on a fluid catalyst cracking (FCC) unit and a method for
regulating catalyst inventory in a FCC unit. Advantageously, the invention
facilitates the removal of excess catalysts from the FCC unit with minimal
process disruption.
[0020] Figure 2 is a simplified schematic of a fluid catalytic cracking
system 230 having a metered catalyst withdrawal system 240. The fluid
catalytic cracking system 230 generally includes a fluid catalytic cracking (FCC)
unit 210 coupled to a catalyst injection system 200 and the metered catalyst
withdrawal system 240, a controller 220, a petroleum feed stock source 204, an
exhaust system 214 and a distillation system 216. One or more catalysts from
the catalyst injection system 200 and petroleum from the petroleum feed stock
source 204 are delivered to the FCC unit 210. The petroleum and catalysts are
reacted in the FCC unit 210 to produce a vapor that is collected and separated
into various petrochemical products in the distillation system 216.
[0021] The heaviest products recovered in the distillation system 216 are
generally tested to determine the amount of entrained catalyst. In one
embodiment, the testing may be carried out daily or once a shift in a refinery
laboratory 218. It is contemplated the amount of entrained catalyst may be
determined by other methods, such as, but not limited to some form of online
analysis. The metric of entrained catalyst is provided from the laboratory 218 to
the controller 220 for using in regulating the catalyst within the FCC unit as
further described below.
[0022] The exhaust system 214 is interface with an exhaust 212 of the
regenerator 250 and is adapted to monitor the composition of materials
exhausted from the regenerator 250. In one embodiment, the exhaust system
214 is configured to detect a metric of catalyst exiting the regenerator 250
through the exhaust. This metric may be obtained by determining the amount
of catalyst particles and/or catalyst fines entrained in the regenerator exhaust.
As such, the exhaust system 214 may include a third or fourth stage separator,
for example, a cyclone separator 232 and a scrubber 234. The metric of
catalyst exiting the regenerator 250 can be provided to the controller 220 and
5

Date of Deposit: 14 July 2006 Attorney Docket No. CAT/013PCT
Express Mail Label: EV840619730US
utilized to balance the amount of catalyst within the FCC unit 210 as further
described below.
[0023] The FCC unit 210 includes a regenerator 250 and a reactor 252 as
known in the art. The reactor 252 primarily houses the catalytic cracking
reaction of the petroleum feed stock and delivers the cracked product in vapor
form to the distillation system 216. Spend catalyst from the cracking reaction is
transferred from the reactor 252 to the regenerator 250, where the catalyst is
rejuvenated by removing coke and other materials. The rejuvenated catalyst is
reintroduced into the reactor 252 to continue the petroleum cracking process.
By-products from the catalyst rejuvenation process are exhausted from the
regenerator 250 through an effluent stack.
[0024] The FCC unit 210 includes a catalyst injection system 200 that
maintains a semi continuous addition of fresh catalyst to the catalyst inventory
circulating between the regenerator 250 and the reactor 252. The catalyst
injection system 200 includes a main catalyst source 202 and one or more
additive sources 206. The main catalyst source 202 and the additive source
206 are coupled to the FCC unit 210 by a process line 222. A fluid source,
such as a blower or air compressor 208, is coupled to the process line 222 and
provides pressurized fluid, such as air, that is utilized to carry the various
powdered catalysts from the sources 202, 206 through the process line 222 and
into the FCC unit 210.
[0025] Typically, different additives are provided from the addition source
206 to the FCC unit 210 to control the ratio of product types recovered in the
distillation system 216 (i.e., for example, more LPG than gasoline) and to
control the composition of emissions passing through the exhaust system 214,
among other process control attributes. The main catalyst source 202 generally
delivers a Y-zeolite containing catalyst, which drives the main cracking process.
Examples of catalyst injection systems that may be adapted to benefit the
invention are described in United States Patent No. 5,389,236, issued February
14, 1995; United States Patent No. 6,358,401, issued March 19, 2002; United
States Patent Application No. 10/304,670 filed November 2, 2002; United
States Patent No. 6,859,759 issued February 22, 2005; United States Patent
Application Serial No. 10/445,543, filed May 27, 2003; and United States Patent
6

Date of Deposit: 14 July 2006 Attorney Docket No. CAT/013PCT
Express Mail Label: EV840619730US
Application Serial No. 10/717,250, filed November 19, 2003, all of which are
hereby incorporated by reference in their entireties. Other suitable catalyst
injection systems that may be adapted to benefit the invention are available
from Intercat Equipment Corporation, located in Sea Girt, New Jersey.
[0026] The controller 220 is utilized to regulate the addition of catalysts
and/or additives made by the injection system 200 and withdrawals made by
the metered catalyst withdrawal system 240 so that the dynamic equilibrium of
catalyst within the FCC unit 210 may be maintained. As the controller 220 is
generally positioned proximate the catalyst sources 206, 202 and the FCC unit
210, the controller 220 is typically housed in an explosion-proof enclosure to
prevent spark ignition of gases which may potentially exist on the exterior of the
enclosure in a petroleum processing environment. The controller 220 may be
equipped with remote access capability so that activity may be monitored from
other locations, such as operations center or by catalyst suppliers. A controller
having such capability is described in United States Patent No. 6,859,759,
issued February 22, 2005 and United States Patent Application Serial No.
10/304,670, filed November 26, 2002, both of which are hereby incorporated by
reference in their entireties.
[0027] The regenerator 250 may be equipped with one or more sensors
that provide a metric indicative of a catalyst level within the regenerator 250. In
the embodiment depicted in Figure 2, the regenerator 250 includes a first
sensor 242 and a second sensor 244 configured to detect when the level of
catalyst within the regenerator 250 exceeds an upper or lower threshold. The
sensor 242, 244 may be an differential pressure measurement device, optical
transducer, a capacitance device, a sonic transducer or other device suitable
for providing information from which the level or volume of catalyst disposed in
the regenerator 250 may be resolved. For example, if the first sensor 242
provides an indication to the controller 220 that the catalyst level is low, the
controller 220 may initiate a catalyst injection by the catalyst injection system
200. If the second sensor 244 provides an indication to the controller 220 that
the catalyst level is high, the controller 220 may initiate a catalyst withdrawal
from the FCC unit by the catalyst withdrawal system 240, or speed up these
otherwise semi-continuous withdrawal processes.
7

Date of Deposit: 14 July 2006 Attorney Docket No. CAT/013PCT
Express Mail Label: EV840619730US
[0028] The metered catalyst withdrawal system 240 is coupled to the
regenerator 250 by a conduit 254. A metering device 256 is disposed in the
conduit 254 to control the flow of catalyst between the regenerator 250 and the
metered withdrawal system 240. An outlet valve 260 is coupled to the catalyst
withdrawal system 240 and is configured to control the flow of catalyst between
the withdrawal system 240 and the spent catalyst storage/disposal 262. The
metering device 256 and outlet valve 260 may be similarly constructed.
[0029] Figure 3 depicts a larger view of one embodiment of the metered
withdrawal system 240 of Figure 2. The withdrawal system 240 includes a
storage vessel 310 having the metering device 256 and the outlet valve 260
coupled thereto. The storage vessel 310 is typically a metal container suitable
for use at high temperatures having a fill port 314 and a discharge port 316.
Typically, the discharge port 316 is positioned at or near a bottom of the
storage vessel 310. The storage vessel 310 is coupled to a pressure control
apparatus 318 that controls the pressure within the storage vessel 310. The
pressure control apparatus 318 generally pressurizes the storage vessel 310 to
about 5 to about 60 pounds per square inch (about 0.35 to about 4.2 kg/cm2)
during withdrawal operations. The apparatus 318 may intermittently vent the
storage vessel 310 to about atmospheric pressure to accommodate filling the
vessel 310 with catalyst from the regenerator 250.
[0030] The storage vessel 310 is vented through a vent port 312 that is
coupled to the regenerator's exhaust 212 or other suitable effluent stack. A
control valve 308 is provided to regulate (or prevent) flow through the vent port
314 from the storage vessel 310. A cyclone 380 or similar device may also be
inserted in the vent line to minimize catalyst carryover from the storage vessel
310. Recovered fines from the cyclone 380 may be transferred through a
return conduit 382 to the storage vessel 310.
[0031] In one embodiment, the pressure control apparatus 318 is
configured to provide air or other gas into the vessel 310. The air or other gas
may be utilized to fluidize, aerate and/or otherwise cool the withdrawn catalyst
disposed in the vessel 310. The pressure control apparatus 318 may
additionally be configured to control the flow of the air or other gas provided to
8

Date of Deposit: 14 July 2006 Attorney Docket No. CAT/013PCT
Express Mail Label: EV840619730US
the vessel 310, thereby providing the ability to optimize cooling of the withdrawn
catalyst and control environmental conditions within the storage vessel 310.
[0032] The metering device 256 is coupled to the fill port 314 to monitor to
control the amount of catalyst received from the regenerator 250. The outlet
valve 260 is coupled to the discharged port 316 to control the amount of
withdrawn catalyst removed from the storage vessel 310 to the spent catalyst
storage/disposal 262 through an outlet line 304. The metering device 256 may
be an on/off valve such as an everlasting valve, a rotary valve or other device
suitable for removing and/or regulating the amount of catalyst withdrawn from
the FCC unit 210 into the storage vessel 310. The metering device 256 may
determine the amount of catalyst by weight, volume, timed dispense or by other
manners. Depending on the catalyst requirements of the system 230, the
metering device 256 is typically configured to remove about 0.1 to about 30
tons per day of catalyst from the regenerator 250 without interruption of
processing in the FCC unit 210. The metering device 256 typically removes
catalysts from the FCC unit 210 periodically over the course of a planned
production cycle, typically 24 hours, in multiple shots of predetermined amounts
spaced over the production cycle. However, catalysts may also be removed
from the FCC unit 210 in an "as needed" basis as discussed above.
[0033] In the embodiment depicted in Figure 3, the metering device 256 is
a control valve 332 that regulates the amount of catalyst delivered from the
regenerator 250 into the storage vessel 310 by timed actuation. The control
valve 332 may include shear disk (not shown) for opening and closing a valve
orifice. In one embodiment, the shear disk rotates eccentricity while additionally
rotating clear of the orifice to provide a self-lapping, seat cleaning action that
prevents the withdrawn catalyst from grooving the sealing surfaces of the shear
disk and valve seat that could cause the valve leakage. One valve that may be
adapted to benefit from the invention is available from the Everlasting Valve
Company, located in South Plainfield, New Jersey. Other control valves may
alternatively be utilized.
[0034] Generally, the control valve 332 and the outlet valve 260 are
interlocked to prevent simultaneous opening. This allows data to be obtained
between valve 332, 260 openings such that the amount of catalyst entering and
9

Date of Deposit: 14 July 2006 Attorney Docket No. CAT/013PCT
Express Mail Label: EV840619730US
leaving the storage vessel 310 may be accurately resolved. In one
embodiment, the outlet valve 260 is opened while the pressure regulating
system 240 provides air at about 60 psi (about 4.2 kg/cm2) into the interior of
the storage vessel 310 to cause catalyst to flow from the storage vessel 310
through the valve 260 and into the spent catalyst storage/disposal 262 via the
outlet line 304.
[0035] Referring back to Figure 2, the metered withdrawal system 240
includes one or more sensors 264 for providing a metric suitable for resolving
the amount of catalyst passing through the metering device 256 during each
withdrawal of catalyst from the regenerator 250. The sensors 264 may be
configured to detect the level (i.e., volume) of catalyst in the storage vessel 310,
the weight of catalyst in the storage vessel 310 and/or the rate of catalyst
movement through at least one of the storage vessel 310, the fill port 314, the
discharge port 316, the metering device 256, the outlet valve 260, the conduit
254 or outlet line 304.
[0036] In the embodiment depicted in Figure 3, the sensor 264 is a plurality
of load cells 306 adapted to provide a metric indicative of the weight of catalyst
in the storage vessel 310. The load cells 306 are respectively coupled to a
plurality of legs 336 that supports the storage vessel 310 above a surface 320,
such as a concrete pad. Each of the legs 336 has one load cell 326 coupled
thereto. The controller 220 receives the outputs of the load cells 326 and
utilizes sequential data samples obtained therefrom to resolve the net amount
of withdrawn catalyst after each actuation of the metering device 256. Data
samples are also taken after actuation of the outlet valve 260 such that the true
amount of catalyst withdrawn from the FCC unit 210 through the system 240
may be accurately determined. Additionally, the net amount of catalyst
withdrawn over the course of the production cycle may be monitored so that
variations in the amount of catalyst dispensed in each individual shot may be
compensated for by adjusting the delivery attributes of the metering device 256,
for example, changing the open time of the control valve 332 to allow more (or
less) catalyst to pass therethrough and be removed from the FCC unit 210.
[0037] Alternatively, the sensor 264 may be a level sensor 328 coupled to
the storage vessel 310 and adapted to detect a metric indicative of the level of
10

Date of Deposit: 14 July 2006 Attorney Docket No. CAT/013PCT
Express Mail Label: EV840619730US
catalyst within the storage vessel 310. The level sensor 328 may be a
differential pressure measuring device, an optical transducer, a capacitance
device, a sonic transducer or other device suitable for providing information
from which the level or volume of catalyst disposed in the storage vessel 310
may be resolved. By utilizing the sensed difference in the level of catalyst
disposed in the storage vessel 310 after dispenses, the amount of catalyst
removed from the regenerator 250 may be resolved for a known storage vessel
geometry.
[0038] Alternatively, the sensor 264 may be a flow sensor 330 adapted to
detect the flow of catalyst through one of the components of the catalyst
withdrawal system 240. The flow sensor 330 maybe a contact or non-contact
device and may be mounted to the storage vessel 310, the metering device 256
or the conduit 254 coupling the storage vessel 310 to the waste container. In
the embodiment depicted in Figure 3, the flow sensor 330 may be a sonic flow
meter or capacitance device adapted to detect the rate of entrained particles
(i.e., catalyst) moving through the delivery line 308.
[0039] Returning to Figure 2, a heat dissipater 258 is coupled to or
positioned approximate to the conduit 254. The heat dissipater 258 is
configured to extract heat from the catalyst within conduit 254, thereby reducing
the temperature of the catalyst flowing from the regenerator 250 to the metered
withdrawal system 240.
[0040] Referring additionally to Figure 3, the heat dissipater 258 may be
positioned proximate the conduit 254 between the regenerator 250 and the
metering device 256, or positioned proximate the conduit 254 between the
metering device 256 and the storage vessel 310. In another embodiment, the
conduit 254 may be coiled or define a torturous path such that the heat
dissipater 258 may be interfaced with a greater length of conduit than if the
conduit was routed in a straight line path as shown in Figure 2, thereby
improving the amount of heat transferred therebetween.
[0041] The heat dissipater 258 may include at least one or more
temperature regulating features. For example, the heat dissipater 258 may
include heat transfer fins 342. In another embodiment, the heat dissipater 258
may include one or more conduits 344 coupled to a fluid source 346 through
11

Date of Deposit: 14 July 2006 Attorney Docket No. CAT/013PCT
Express Mail Label: EV840619730US
which a heat transfer fluid is flowed. By reducing the temperature of catalyst
being withdrawn from the regenerator 250, the design constraint of the
withdrawal system 240 may be relaxed accordingly with the reduction in catalyst
temperature entering the vessel 310.
[0042] Similarly, the storage vessel 310 may also be equipped with a
thermal regulating device 358 to reduce the temperature of the storage vessel
310. The thermal regulating device 358 may be configured similar to the heat
dissipater 258 described above. For example, the thermal regulating device
358 may include heat transfer fins 360. In another embodiment, the thermal
regulating device 358 may include one or more conduits 362 coupled to a fluid
source 364 through which a heat transfer fluid is flowed.
[0043] The storage vessel 310 may alternatively and/or additionally be
cooled as described above by providing fluid from the pressure control
apparatus 318 into the vessel 310. The control valve 308 may also be
periodically opened to allow heated gases disposed on the interior volume of
the vessel 310 to be removed and replace by cooler gas provided from the
pressure control apparatus 318.
[0044] The temperature of the gas and/or catalyst entering vessel 310 may
be monitored using a sensor 384. If the controller 220 determines, in response
to a metric of temperature provided by the sensor 384, that the temperature of
the gas and/or catalyst entering the vessel exceed a predefined limit, then a
remedial action may be initiated. For example, remedial actions may include at
least one of shutting off the flow through into the vessel 310 to allow the system
to cool before restarting, reducing the flowrate of catalyst into vessel 310 using
the regulating device 256, increasing the heat extraction rate of the heat
dissipater 258 or adding an extra flow of cold air to the catalyst leaving the
regenerator to cool it down through jets 386 formed in the conduit 254.
[0045] Returning to Figure 2, the controller 220 is provided to control the
function of at least the withdrawal system 240. The controller 220 may be any
suitable logic device for controlling the operation of the catalyst withdrawal
system 240. In one embodiment, the controller 220 is a programmable logic
controller (PLC), such as those available from GE Fanuc. However, from the
disclosure herein, those skilled in the art will realize that other controllers such
12

Date of Deposit: 14 July 2006 Attorney Docket No CAT/013PCT
Express Mail Label: EV840619730US
as microcontrollers, microprocessors, programmable gate arrays, and
application specific integrated circuits (ASICs) may be used to perform the
controlling functions of the controller 220. It is contemplated that the injection
system 200 and the withdrawal system 240 may have separate controllers,
which may, or may not, be linked.
[0046] The controller 220 is coupled to various support circuits that provide
various signals to the controller 220. These support circuits include, power
supplies, clocks, input and output interface circuits and the like. Other support
circuits couple to the temperature sensor 384, the sensors 264, the metering
device 256, the outlet valve 260, the pressure control apparatus 318 and the
like, to the controller 220.
[0047] Figure 4 is flow diagram of one embodiment of a method 400 for
regulating catalyst within a FCC unit. The method 400 begins at step 402 by
obtaining a metric of catalyst lost and/or removed from the FCC unit. The
metric of catalyst lost may be a predefined value. For example, based on
empirical data, or calculated data, or maybe a provided real time and/or as an
updated metric. Examples of updated and/or provided metrics include a metric
of catalyst entrained in the product stream at the distiller, catalyst exiting the
regenerator through the exhaust system, catalyst removed from the metered
withdrawal system, among others.
[0048] At step 404, a metric of catalyst additions are obtained. The metric
of catalyst addition are typically attained from the catalyst addition system, in
the form of catalyst and/or additives added to the FCC unit.
[0049] At step 406, an amount of catalyst within the FCC unit is
determined. In one embodiment, the amount of catalyst is determined by
summing the catalyst additions obtained at step 404 minus the catalyst
removed from the system obtained at step 402. The determination of catalyst
within the FCC unit may be made from data obtained over a predetermined
period of time. The predetermined period of time may be in fractions of an
hour, hourly, daily or over other time periods. The determination of catalyst
within the FCC unit may be made from data obtained real time, for example, by
monitoring a data stream such as regenerator bed level. As the process
described above is iterative, the total catalyst determined may, alternatively, be
13

Date of Deposit: 14 July 2006 Attorney Docket No. CAT/013PCT
Express Mail Label: EV840619730US
calculated by subtracting the catalyst removed over the period from the last
determination and adding the catalyst added over the same period.
[0050] At step 408, the catalyst amount is compared against a threshold
value or process window. If the determined catalyst is outside of a predefined
process window (or exceeds the threshold), appropriate catalyst additions or
withdrawals are made at step 410. This cycle of monitoring the amount of
catalyst is repeated in order to maintain the dynamic catalyst equilibrium in the
FCC unit. Advantageously, this allows the FCC unit to continue operating at or
near processing limits with minimal fluctuation, thereby providing the desired
product mix and emissions composition with minimal dis-optimisation, thereby
maximizing the profitability of the FCC system refiner.
[0051] In another embodiment of a method for regulating catalyst within a
FCC unit, the withdrawal system 240 may be set to remove a predefined
amount of catalyst over a predefined period of time. For example, the
withdrawal system 240 may be set to remove a target withdrawal of about 4
tons of catalyst per day. The withdrawal may be made in predetermined
increments, such that a total withdrawal amount will be made over the
predefined period. In one embodiment the operator may manually initiate
withdrawals from the regenerator 250 using the system 240. For example, the
operator may initiate a withdrawal in response to the catalyst bed level within
the regenerator 250, such as provided by information obtained by the sensor
244, The manual withdrawal may be made in addition to the target withdrawal,
or count against the target withdrawal for that time period.
[0052] Although the teachings of the present invention have been shown
and described in detail herein, those skilled in the art can readily devise other
varied embodiments that still incorporate the teachings and do not depart from
the scope and spirit of the invention.
14

Date of Deposit: 14 July 2006 Attorney Docket No. CAT/013PCT
Express Mail Label: EV840619730US
What is claimed is:
1. A catalyst withdrawal apparatus for removing catalyst from a fluid
catalyst cracking (FCCU) unit, comprising:
a pressure vessel suitable for high temperature operation;
a fill port and a discharge port defined in the pressure vessel;
a metering device coupled to the fill port;
a heat dissipater located adjacent the metering device and adapted to
cool catalyst entering the pressure vessel; and
a sensor coupled to the pressure vessel arranged to provide a metric
indicative of catalyst entering the pressure vessel through the metering device.
2. The apparatus of claim 1, wherein the sensor further comprises:
at least one of a load cell, a differential pressure sensor, flow sensor or a
level sensor.
3. The apparatus of claim 1, wherein the heat dissipater further comprises:
one or more heat transfer fins.
4. The apparatus of claim 1, wherein the heat dissipater further comprises:
a conduit adapted to flow a heat transfer fluid therethrough.
5. The apparatus of claim 1, wherein the metering device further
comprises:
a valve coupled to the fill port.
6. The apparatus of claim 1 further comprising:
a vent port adapted for coupling to an effluent stack or other safe
location; and
a pressure control apparatus coupled to the pressure vessel and suitable
for establishing a pressure within the vessel in excess of 5 pounds per square
inch.
15

Date of Deposit: 14 July 2006 Attorney Docket No. CAT/013PCT
Express Mail Label: EV840619730US
7. The apparatus of claim 1 further comprising:
a cooling system arranged to regulate a temperature of the pressure
vessel.
8. The apparatus of claim 1, wherein the cooling system further comprises
as least one of fins coupled to the pressure vessel or a cooling jacket.
9. A fluid catalyst cracking system comprising:
a fluid catalyst cracking unit (FCCU) having a reactor coupled to a
regenerator; and
a catalyst withdrawal apparatus coupled to the FCCU and configured to
meter catalysts removed from the FCCU.
10. The system of claim 9 further comprising:
a heat dissipater disposed between the catalyst withdrawal apparatus
and the reactor, the heat dissipater adapted to cool catalyst moving between
the catalyst withdrawal apparatus and the reactor.
11. The system of claim 10, wherein the heat dissipater further comprises:
one or more heat transfer fins.
12. The system of claim 10, wherein the heat dissipater further comprises:
a conduit adapted to flow a heat transfer fluid therethrough.
13. The system of claim 9 further comprising:
a metering device disposed between the catalyst withdrawal apparatus
and the FCCU, the metering device adapted to regulate flow of catalyst moving
between the catalyst withdrawal apparatus and the FCCU.
14. The system of claim 13, wherein the metering device further comprises:
a valve coupled to the catalyst withdrawal apparatus and adapted to
selectively open a passage defined between the catalyst withdrawal apparatus
and the FCCU.
16

Date of Deposit: 14 July 2006 Attorney Docket No. CAT/013PCT
Express Mail Label: EV840619730US
15. The system of claim 13 further comprising:
a sensor arranged to provide a metric indicative of catalyst entering the
the catalyst withdrawal apparatus.
16. The system of claim 15, wherein the sensor further comprises:
at least one of a load cell, a differential pressure sensor, a flow sensor or
a level sensor.
17. The system of claim 9, wherein the catalyst withdrawal apparatus further
comprises:
a pressure vessel; and
a vent port disposed in the pressure vessel and coupled to an effluent
stack or other safe location.
18. A method for controlling an amount of catalyst in a fluid catalytic cracking
unit, comprising:
determining a change of catalyst present in a catalytic cracking unit
(FCCU);
withdrawing catalyst from the FCCU into an isolatable storage vessel
coupled to the FCCU;
measuring the amount of catalyst disposed in the storage vessel; and
removing the measured catalyst from the storage vessel.
19. The method of claim 18, wherein the step of measuring further
comprises:
sensing a metric of catalyst disposed in the storage vessel.
20. The method of claim 19, wherein the step of sensing further comprises:
determining a change in weight of the storage vessel.
17

Date of Deposit: 14 July 2006 Attorney Docket No. CAT/013PCT
Express Mail Label: EV840619730US
21. The method of claim 19, wherein the step of withdrawing further
comprises:
venting the storage vessel.
18

A catalyst withdrawal apparatus and method for regulating catalyst inventory in a fluid catalytic cracking catalyst (FCC) unit is provided. In one embodiment, a catalyst withdrawal apparatus for removing catalyst from a FCC unit includes a pressure vessel having a metering device coupled to a fill port.
A heat dissipater is located adjacent the metering device and is adapted to cool
catalyst entering the pressure vessel. A sensor is coupled to the pressure vessel arranged to provide a metric indicative of catalyst entering the pressure vessel through the metering device. In another embodiment, a method for
regulating catalyst inventory in a FCC unit includes the steps of determining a change of catalyst present in a FCC unit, withdrawing catalyst from the FCC unit into an isolatable storage vessel coupled to the FCC unit, measuring the amount of catalyst disposed in the storage vessel, and removing the measured
catalyst from the storage vessel.

Documents:

00125-kolnp-2008-abstract.pdf

00125-kolnp-2008-claims.pdf

00125-kolnp-2008-correspondence others.pdf

00125-kolnp-2008-description complete.pdf

00125-kolnp-2008-drawings.pdf

00125-kolnp-2008-form 1.pdf

00125-kolnp-2008-form 3.pdf

00125-kolnp-2008-form 5.pdf

00125-kolnp-2008-gpa.pdf

00125-kolnp-2008-international publication.pdf

00125-kolnp-2008-international search report.pdf

00125-kolnp-2008-pct request form.pdf

125-KOLNP-2008(28-02-2014)-CLAIMS.pdf

125-KOLNP-2008(28-02-2014)-CORRESPONDENCE.pdf

125-KOLNP-2008-(13-05-2013)-ABSTRACT.pdf

125-KOLNP-2008-(13-05-2013)-CLAIMS.pdf

125-KOLNP-2008-(13-05-2013)-CORRESPONDENCE.pdf

125-KOLNP-2008-(13-05-2013)-DESCRIPTION (COMPLETE).pdf

125-KOLNP-2008-(13-05-2013)-DRAWINGS.pdf

125-KOLNP-2008-(13-05-2013)-FORM 13.pdf

125-KOLNP-2008-(13-05-2013)-FORM 2.pdf

125-KOLNP-2008-(13-05-2013)-FORM 3.pdf

125-KOLNP-2008-(13-05-2013)-OTHERS.pdf

125-KOLNP-2008-(13-05-2013)-PETITION UNDER RULE 137-1.1.pdf

125-KOLNP-2008-(13-05-2013)-PETITION UNDER RULE 137.pdf

125-KOLNP-2008-ASSIGNMENT.pdf

125-KOLNP-2008-CORRESPONDENCE OTHERS 1.2.pdf

125-KOLNP-2008-CORRESPONDENCE OTHERS-1.1.pdf

125-KOLNP-2008-FORM 3 1.1.pdf

125-KOLNP-2008-PCT REQUEST 1.1.pdf

abstract-00125-kolnp-2008.jpg


Patent Number 259332
Indian Patent Application Number 125/KOLNP/2008
PG Journal Number 11/2014
Publication Date 14-Mar-2014
Grant Date 07-Mar-2014
Date of Filing 08-Jan-2008
Name of Patentee INTERCAT EQUIPMENT INC.
Applicant Address 104 UNION AVENUE, MANASQUAN NJ
Inventors:
# Inventor's Name Inventor's Address
1 EVANS MARTIN 125 ANDERSON ROAD, TOLLAND, CT 06084
PCT International Classification Number B32B 5/02,B32B 27/04
PCT International Application Number PCT/US2006/027542
PCT International Filing date 2006-07-14
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 11/184125 2005-07-19 U.S.A.