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Title:
REMOVING PARTICULATE MATERIAL FROM VESSELS
Document Type and Number:
WIPO Patent Application WO/2019/016327
Kind Code:
A1
Abstract:
An unloading system for unloading particulate material from a vessel (10), the unloading system comprising a hoses assembly (20, 30, 40) arranged to be lowered into the vessel for vacuuming the particulate material from the vessel, the hoses assembly comprising one or more bendable parts (21, 32, 43), the unloading system further comprising one or more actuators (22, 51, 61, 71, 74, 81) fixed to the one or more bendable parts for steering the one or more bendable parts, wherein the actuators are controllable by a control system (16) that is arranged to be located outside of the vessel.

Inventors:
GROOTHUIS STEFAN SEBASTIAAN (NL)
Application Number:
PCT/EP2018/069663
Publication Date:
January 24, 2019
Filing Date:
July 19, 2018
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
MOURIK INT B V (NL)
International Classes:
B08B9/08; B01J8/00
Domestic Patent References:
WO2007062179A22007-05-31
Foreign References:
EP2224454A12010-09-01
US20040134518A12004-07-15
DE202014105987U12016-03-14
EP1215683A22002-06-19
EP1491463A22004-12-29
JPS61185330A1986-08-19
Other References:
None
Attorney, Agent or Firm:
HAARTSEN, Jan Pieter et al. (NL)
Download PDF:
Claims:
CLAIMS

1. An unloading system for unloading particulate material from a vessel (10), the unloading system comprising a hoses assembly (20, 30, 40) arranged to be lowered into the vessel for vacuuming the particulate material from the vessel, the hoses assembly comprising one or more bendable parts (21, 32, 43), the unloading system further comprising one or more actuators (22, 51, 61, 71, 74, 81) fixed to the one or more bendable parts for steering the one or more bendable parts, wherein the actuators are controllable by a control system (16) that is arranged to be located outside of the vessel.

2. The unloading system according to claim 1 , wherein the one or more actuators comprise actuation cables (22, 51, 61, 71, 74) that are guided along the hoses assembly and fixed near an end of a bendable part of the hoses assembly for steering the one or more bendable parts by pulling one or more of the actuation cables under control of the control system.

3. The unloading system according to claim 2, wherein the hoses assembly comprises guiding means (52, 62) fixed to the outside of the hoses assembly for guiding the actuation cables along the outside of the hoses assembly.

4. The unloading system according to claim 2, wherein the hoses assembly comprises a guiding system on the inside of the hoses assembly for guiding the actuation cables along the inside of the hoses assembly. 5. The unloading system according to any one of the preceding claims, wherein the one or more actuators comprise at least one of:

pneumatic actuators (81);

hydraulic actuators;

electrical actuators; and

thermo-electric actuators,

wherein the pneumatic, hydraulic, electrical, and/or thermo-electric actuators are fixed along a bendable part of the hoses assembly for steering the bendable part by expanding or contracting the actuators under control of the control system.

6. The unloading system according to any one of the preceding claims, comprising a first set of one or more actuators for steering a first bendable part of the hoses assembly and a second set of one or more actuators for steering a second bendable part of the hoses assembly.

7. The unloading system according to any one of the preceding claims, comprising at least three actuators that are longitudinally arranged along the hoses assembly at a substantially same radial distance from each other.

8. The unloading system according to any one of the preceding claims, wherein the hoses assembly comprises one or more hoses (20, 31, 32, 41, 42, 43) that are arranged to be rigidly coupled, wherein at least one of the one or more hoses is a steerable bendable part (21, 32, 42).

9. The unloading system according to claim 8, wherein at least one of the hoses is non-steerable.

10. The unloading system according to any one of the preceding claims, further comprising an anti-clogging tool (90) fixed near the end of the hoses assembly and arranged to loosen the particulate material before being vacuumed, the anti-clogging tool being controllable by the control system.

11. The unloading system according to any one of the preceding claims, further comprising a stabilization system for stabilizing at least a part of the hoses assembly inside of the vessel with respect to a wall of the vessel.

12. The unloading system according to claim 11, wherein the stabilization system is arranged to be positioned around the hoses assembly and comprises one or more arms that are extendable in a direction predominantly perpendicular to the hoses assembly for releasably fixating the stabilization system to the wall of the vessel.

13. The unloading system according to claim 11 or 12, wherein the stabilization system comprises a gripper for opening one or more tray sections or hatches inside of the vessel, the gripper being controllable by the control system.

14. The unloading system according to any one of the claims 1-13, wherein the particulate material comprises catalyst particles, and wherein the vessel is a packed bed reactor.

15. A method of unloading particulate material from a vessel using an unloading system according to any one of the claims 1-14.

Description:
REMOVING PARTICULATE MATERIAL FROM VESSELS

TECHNICAL FIELD

[0001] The invention relates to removing particulate material, such as spent catalyst, from vessels, such as packed bed reactors. In particular, the invention relates to an unloading system for unloading particulate material from a vessel, and a method of unloading particulate material from a vessel.

BACKGROUND ART

[0002] Chemicals are often manufactured on an industrial scale by reaction in large industrial catalytic reactors. One type of reactors used in catalytic processes is a fixed bed reactor, in which catalyst is an immobile bulk. This is different from, for instance, a continuous stirred tank reactor, in which liquid and/or gas reactants are stirred. Note that catalyst may be regenerated continuously in a continuous catalyst regeneration (CCR) reactor which means that the catalyst is constantly on the move. However, if the catalyst bulk is relatively large, and therefore static compared to the catalyst regeneration flow, the reactor may still be called a fixed bed reactor.

[0003] Two main groups of fixed bed reactors can be distinguished according to the thermal properties of the process. A process can be adiabatic, during which no heat is exchanged with the environment, or diabatic, during which heat is (or should be) exchanged with the environment. The two reactor groups are then the (adiabatic) packed bed (any reactor with a bulk of catalyst) and the (multi-)tubular fixed bed reactor (any reactor having catalyst inside small (relative to the reactor diameter) tubes). Within these groups, many different types and forms can be distinguished. Often, packed bed reactors are called fixed bed reactors, while multi-tubular fixed bed reactors are simply called tubular reactors.

[0004] Adiabatic packed bed reactors are favored if the life of the catalyst is longer than three months and if the pressures are high. In these reactors, that may be 4 m in diameter and 50 m high, it is particularly important that the catalyst strength and porosity are maximized, the pressure drop across the reactor is minimized, and the pore diffusion resistance is low. The requirement on the pressure drop often results in a reactor that has a large diameter and a relatively low bed height. Very often, the catalyst is held in place inside the reactor by a layer of inert ceramic balls, placed both below and on top of the catalyst bed. This stabilization enables the use of a feed flow from the bottom to the top of the reactor. Without this stabilization, feed should flow from top to bottom to prevent fluidization of the catalyst (moving around of catalyst driven by the feed flow). To spread out the feed flow evenly across the catalyst, mesh baskets and distributors are used near the bed at the entry point (and above lower beds).

[0005] In general, a packed bed reactor is adiabatic, meaning that during the process, no heat is exchanged with the environment. In the majority of packed bed reactors, the reactor may have multiple levels of fixed catalyst to be able to regulate the temperature of the flow (cool down, or heat up) in between the beds so as to keep the temperature in a specified range, or mix the higher bed effluents with quench gases.

[0006] Catalytic reactors are usually bespoke structures designed for particular chemical processes or site requirements and hence individual reactors can vary greatly in their dimensions. In principle, such a reactor can be of any size, and in particular can be bigger or smaller than the typical sizes given above, the limitations being associated with physical construction limits and reaction requirements. There has been a general trend in the last years, particularly in the petrochemical industry, to increase catalytic reactor sizes.

[0007] Unloading catalyst from a packed bed reactor is a dangerous, labor intensive, time consuming and therefore costly operation. It may be required to enter the reactor under an inert environment (an environment that causes no chemical reactions, which is often done by removing all oxygen from the environment with, in general, nitrogen), because the catalyst can be (or have gotten) pyrophoric under a normal air environment with oxygen. Sometimes the inert environment is required to protect the catalyst not from heating up or burning, but from activating, such that regeneration or disposal may be more effective. Entering the reactor under an inert environment may also be done to save time; the catalyst (or actually the sulfur that is deposited on the catalyst by the process) can be burned in a controlled way by adding oxygen to the feed. This takes some time, after which the reactor also needs to cool down. This does mean, however, that the reactor can be unloaded without nitrogen. In practice, 0% oxygen is not feasible, so often 4% oxygen combined with a Lower Explosion Limit (LEL) of 10% of the substance is taken as safe entry environment (regarding explosions or fire), where "safe" is still a relative notion. The catalyst can also be passivated by feeding oil mixed with a coating that deposits on the catalyst and disables its pyrophoric state. The inert environment is then not necessary anymore, but this is an expensive procedure and is, therefore, hardly used.

[0008] The person performing the entry is typically supported by three others, making the B A team (breathing apparatus) a four person team. One person is inside the reactor with full BA equipment, while another person (also with full BA equipment) is the backup near the manhole who can help in case of a problem with the person doing the first entry, and is ready to enter the reactor. These two are communicating with another person (without BA equipment) at the top of the reactor but outside the unsafe area, and with a person inside the Life Support Unit (LSU), who takes care of the air flow and general supervision and collection of information. The person entering the reactor is most likely an experienced person and is, therefore, not too uncomfortable performing the entry. However, some persons following and successfully passing a BA training do get uncomfortable when entering a reactor under nitrogen conditions for the first time, even up to the point that they will never go inside again.

[0009] With reference to Fig. 1 , a known method for unloading catalyst from a packed bed reactor is vacuum unloading (e.g. at 3.5 to 5 m 3 /h) using flexible pipes or hoses to vacuum the catalyst from the top 11 out of a reactor 10. Vacuuming is performed by a person 12 guiding vacuum tubing 13 inside the reactor 10 close to the catalyst 14 to vacuum it out. Optionally, part of the catalyst may be removed by gravity dumping, wherein catalyst falling down is removed by a further vacuum system 15 at the bottom of the reactor.

[0010] When vacuuming a "sweet reactor" (a reactor purged with nitrogen), two pipes may be used: one for vacuuming, and the other for nitrogen return, which adds part of the nitrogen that has been removed from the reactor by vacuuming the catalyst, back into the top of the reactor. Sometimes wet unloading is done, during which water is used to spray the catalyst out. A combination of these methods may be used.

[0011] Often the catalyst is not free flowing, and is either very hard, making it difficult to break apart, or a wet and soft sludge, causing blockage in vacuum pipes or dump nozzles. If it is hard, it may need to be hit to break it apart. This can be done by the person inside the reactor with a jackhammer or a normal hammer, and is not a precise task. In general, this is done in places that are easily reached, and one needs to take care that the catalyst is struck from top to bottom, and not vice versa, to prevent an avalanche effect. [0012] There is a need for a more efficient catalyst unloading method, wherein the number of personnel can be minimized, the safety levels can be improved and the time needed for unloading can be lowered.

SUMMARY OF INVENTION

[0013] The invention enables particulate material to be removed from vessels, such as packed bed reactors, in a safe, labor efficient and time efficient manner. Examples of particulate material are catalyst particles, ceramics, grit and dust. Other examples of particulate material are agricultural products, such as corn or wheat, in which case the vessel may be a silo.

[0014] According to an aspect of the invention, an unloading system is proposed for unloading particulate material from a vessel. The unloading system can comprise a hoses assembly arranged to be lowered into the vessel for vacuuming the particulate material from the vessel. The hoses assembly can comprise one or more bendable parts. The unloading system can further comprise one or more actuators fixed to the one or more bendable parts for steering the one or more bendable parts. The actuators can be controllable by a control system that is arranged to be located outside of the vessel.

[0015] Advantageously, the vessel can thus be unloaded without a person entering the vessel.

[0016] In an embodiment, the one or more actuators can comprise actuation cables that are guided along the hoses assembly and fixed near an end of a bendable part of the hoses assembly for steering the one or more bendable parts by pulling one or more of the actuation cables under control of the control system.

[0017] In an embodiment, the hoses assembly can comprise guiding means fixed to the outside of the hoses assembly for guiding the actuation cables along the outside of the hoses assembly.

[0018] In an embodiment, the hoses assembly can comprise a guiding system on the inside of the hoses assembly for guiding the actuation cables along the inside of the hoses assembly.

[0019] In an embodiment, the one or more actuators can comprise at least one of: pneumatic actuators; hydraulic actuators; electrical actuators; and thermo-electric actuators. The pneumatic, hydraulic, electrical, and/or thermo-electric actuators can be fixed along a bendable part of the hoses assembly for steering the bendable part by expanding or contracting the actuators under control of the control system. [0020] In an embodiment, the unloading system can comprise a first set of one or more actuators for steering a first bendable part of the hoses assembly and a second set of one or more actuators for steering a second bendable part of the hoses assembly.

[0021] In an embodiment, the unloading system can comprise at least three actuators that are longitudinally arranged along the hoses assembly at a substantially same radial distance from each other.

[0022] In an embodiment, the hoses assembly can comprise one or more hoses that are arranged to be rigidly coupled. At least one of the one or more hoses can be a steerable bendable part.

[0023] In an embodiment, at least one of the hoses is non-steerable.

[0024] In an embodiment, the unloading system can further comprise an anti- clogging tool fixed near the end of the hoses assembly and arranged to loosen the particulate material before being vacuumed. The anti-clogging tool can be controllable by the control system.

[0025] In an embodiment, the unloading system can further comprise a stabilization system for stabilizing at least a part of the hoses assembly inside of the vessel with respect to a wall of the vessel.

[0026] In an embodiment, the stabilization system can be arranged to be positioned around the hoses assembly. The stabilization system can comprise one or more arms that are extendable in a direction predominantly perpendicular to the hoses assembly for releasably fixating the stabilization system to the wall of the vessel.

[0027] In an embodiment, the stabilization system can comprise a gripper for opening one or more tray sections or hatches inside of the vessel. The gripper can be controllable by the control system.

[0028] In an embodiment, the particulate material can comprise catalyst particles.

The vessel can be a packed bed reactor.

[0029] According to an aspect of the invention, a method of unloading particulate material from a vessel is proposed. The method can use an unloading system having one or more of the above described features.

[0030] Hereinafter, embodiments of the invention will be described in further detail. It should be appreciated, however, that these embodiments may not be construed as limiting the scope of protection for the present invention. BRIEF DESCRIPTION OF DRAWINGS

[0031 ] Embodiments will now be described, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts, and in which:

[0032] Fig. 1 is a cross-sectional side view of a prior art packed bed reactor and unloading method;

[0033] Fig. 2 shows a three-dimensional cross-sectional side view of a packed bed reactor with an unloading system of an exemplary embodiment of the invention;

[0034] Figs. 3 and 4 show three-dimensional cross-sectional side views of a packed bed reactor with exemplary embodiments of hoses assemblies;

[0035] Figs. 5-7 show side views of hoses with exemplary embodiments of guiding actuator cables;

[0036] Fig. 8 shows a three-dimensional side view of a hose including an exemplary embodiment of actuator cables;

[0037] Fig. 9 shows a three-dimensional side view of a hose including an exemplary embodiment of a pneumatic actuator;

[0038] Fig. 10 shows a three-dimensional view of an end of a hose including an exemplary embodiment of an anti-clogging tool; and

[0039] Figs. 11-13 show three-dimensional views of exemplary stabilization systems.

[0040] The figures are meant for illustrative purposes only, and do not serve as restriction of the scope or the protection as laid down by the claims.

DESCRIPTION OF EMBODIMENTS

[0041] The invention enables automated handling of particulate material, wherein the particulate material is removed from a vessel by an unloading system without the need for a person inside the vessel during the removal process. Typically the particulate material to be removed is spent or used particulate material, but in rare occasions it may concern unused or still useful particulate material.

[0042] In the following description and examples the invention is explained for the removal of catalyst from a packed bed reactor using a catalyst unloading system. It will be understood that the invention is not limited to catalyst and similarly applies to other types of particulate material, such as ceramics, grit and/or dust. Other examples of particulate material are agricultural products, such as corn or wheat. Moreover, the invention is not limited to packed bed reactors and similarly applies to other types of vessels.

[0043] The wording "catalyst", "catalyst material", "catalyst bulk" and "catalyst particles" are used interchangeably and have the same meaning. The wording

"unloading" and "removing" in conjunction with particulate material or catalyst are used interchangeably and have the same meaning.

[0044] The process of removing the catalyst from the reactor may include two phases. In a preparation phase the reactor may be prepared to enable the cleaning parts of the catalyst unloading system to enter the reactor and reach the catalyst material. In an unloading phase the catalyst may be removed from the reactor.

[0045] Regarding the preparation phase, depending on the reactor, various internal mechanical components may be present that may need to be manipulated to allow the catalyst unloading system to enter lower sections of the reactor, or which should be cleaned. These internals may include distribution trays and piping, screens (that act as filters), thermocouples, cladding, and cones. Each reactor is different and the components do not adhere to one universal design regarding, for instance, manholes and how to open and close them. Moreover, they can be in hard to reach places.

[0046] An example of a task that may be performed in the preparation phase is the bolting and unbolting of an internal part. To enable bolting and unbolting, the catalyst unloading system may include an end-effector or end-point tool with an integrated wrench, or a gripper holding the proper tool.

[0047] Another example of a task that may be performed in the preparation phase is removing a forelock, which is similar to unbolting. To enable a forelock to be removed, the catalyst unloading system may include an end-effector or end-point tool with an integrated wrench, or a gripper holding the proper tool. The end-effector may be similar to a clamping tool and gripper.

[0048] Another example of a task that may be performed in the preparation phase concerns hatches or tray sections. Hatches or tray sections may have to be unbolted and forelocks may have to be removed before the hatches or tray sections are be free to be handled and manipulated. To open and close the hatches or tray sections, the catalyst unloading system may include an end-effector or end-point tool with an integrated gripper. [0049] Different parts of the catalysts unloading system may be used for the preparation phase and the catalyst removal phase. In an embodiment a first part of the catalyst unloading system enters the reactor first to perform preparation tasks and is removed from the reactor before a second part of the catalyst unloading system enters the reactor to perform the catalyst unloading task. In another embodiment the first part of the catalyst unloading system for performing preparation tasks and the second part of the catalyst unloading system for performing the catalyst unloading task enter the reactor simultaneously. In another embodiment the first part for performing preparation tasks and the second part for performing the catalyst removal task are integrated into one part. In yet another embodiment preparation tasks may be performed by one or more persons, in which case the catalyst unloading system may include only a part for performing the catalyst unloading task.

[0050] After the preparation phase, the catalyst may be removed from the reactor using the catalyst unloading system. In the unloading phase, preferably no persons are required to enter the reactor.

[0051 ] According to an aspect of the invention, the catalyst unloading system includes tubing that is guided through a manhole or other entrance into the reactor to vacuum spent catalyst out of the reactor. Typically the tubing includes at least one flexible part and may include one or more rigid parts. Typically, the reactor manhole is situated at the very top of a reactor. However, sometimes a manhole is placed on the shoulder of the reactor, or on the side.

[0052] The catalyst unloading operation may be performed without a person within the reactor. Hereto, the tubing may be guided within the reactor from outside of the reactor. The accuracy of the movement of the tubing may be low, for example in the range of decimeters. Because the tubing may be heavy and needs to be bent in certain directions to preferably reach every location in the reactor, the force requirements for guiding the tubing may be high, e.g. in the range of hundreds of Newton. Considering that the complete volume in the reactor, including hard to reach locations, is preferably reached, the tubing preferably has many degrees of freedom for both positioning and orientation.

[0053] Fig. 2 shows an exemplary embodiment of the invention, wherein the catalyst unloading system includes a long tube 20 with a flexible tip 21 which can be steered with cables 22 outside, or embedded inside (not shown), the long tube 20. In the example of Fig. 2, the long tube 20 has been inserted into the reactor 10 through a manhole located at the top 11 of the reactor 10. Preferably, the manhole on top 11 of the reactor and in the tray sections 23 are all aligned in a central column along the axis of the reactor, such as shown in Fig. 2. An exemplary reactor is 40 m high, 4 m in diameter, and has 1 m thick tray sections at a depth of 2 m, 15 m, and 27 m. Tray sections 23 may have been opened in a preparation phase to enable the long tube 20 to reach the catalyst 14 to be removed. On the outside of the reactor 10, the tube 20 is connected to a vacuum system and to a control system for controlling the cables 20. The vacuum system and the control system may be two separate systems or integrated into a single vacuum/control system 16, as shown in Fig. 2.

[0054] In an embodiment the tubing may be formed as a hoses assembly including one or more flexible hoses that may be lowered into the fixed bed reactor through a manhole. The assembly may be steered by actuators such that the tip of the assembly (the open end of the hose assembly through which catalyst is to be vacuumed) can be placed at desired locations in the reactor. A double bend in the hoses assembly may be necessary to reach difficult to reach locations. Preferably, the hoses assembly includes a flexible part that may be positioned with six degrees of freedom.

[0055] To perform the bending, actuation parts may be used to pull or push the tip of the assembly. Cables 22, e.g. steel cables or cables from any other suitable material, may be used to pull the hose into the desired direction. Alternatively or additionally, pneumatic, hydraulic, electrical, thermo-electric, or any other suitable actuators may be used to pull or push the hose into the desired direction. The actuation system may be attached to the one or more hoses and acts with respect to the hoses, i.e. a distributed actuation load may move the hoses, as opposed to a single force at, e.g. the tip with respect to the reactor. The actuation system may be able to control a distal part of the hoses assembly remotely, i.e. from outside of the reactor.

[0056] The one or more flexible hoses may be actuated by cables spaced at a certain radial distance from the hoses, preferably uniformly spaced angularly around the hoses. Using four cables is found to be preferable for ease of control (perpendicular pulling directions), but it is noted that only three cables per hose are necessary for full positioning capabilities. It is possible to use more than four cables, although three or four cables are found to be sufficient. [0057] In an embodiment the hoses assembly includes only a limited length of steerable hose near the bottom of the hoses assembly. The remaining length at the top of the hoses assembly may then be substantially straight without a need for being bendable or steerable.

[0058] In case the hoses assembly includes multiple hoses, the hoses may be rigidly coupled to form a single long tube 20. The hoses assembly may include one or more steerable hoses and zero or more non-steerable hoses, depending on the required length of the long tube 20, which depends on the height of the reactor, and the required mobility of the steerable part of the long tube 20, which depends on the diameter of the reactor.

[0059] Each of the steerable and non-steerable hoses may include guiding means for guiding the actuation cables along the hoses in the lengthwise direction. Preferably the guiding means are substantially uniformly distributed along the hoses. The lengthwise part of a hose in between two subsequent guiding means is also called a hose segment. An example of a guiding means is an eye, for example in the form of an eye bolt or an eye nut attached to the hose. The actuation cables along the steerable hoses may then be guided by the eyes and attached to the hose near the tip of the hose. The actuation cables provide a force (a tension) along the direction of the cables, so the part of the hose to which a cable is attached is subject to a force in the direction of the cable. The other parts of the hose to which the cable is not fixed but is guided in a guiding eye are subject to perpendicular force components due to the bending of the hose as a whole. This bending is caused by the bending of the segment to which a cable is fixed, and due to the perpendicular force on a cable's eye because of the bending of a segment, that segment is also bent which causes this chain of events. Thus, the hoses may bend because actuation cables will try to straighten as much as possible, which pulls the guiding eyes, and thereby the hose, along.

[0060] Fig. 5 shows an exemplary embodiment of how actuation cables 51 may be guided along a hose 50. Guiding means, in this example in the form of eyes 52, may be secured to the hose 50, e.g. using a clamping ring 53 or any other suitable fixation means. The cables 51 may be guided through eyes 52 in a linear manner, i.e. from one eye to the next eye in longitudinal direction along the hose 50 wherein the eyes used for guiding a cable 51 are linearly arranged along the hose in the longitudinal direction. Cables 51 may cross at one or more positions, such as shown in Fig. 7. Each cable 51 may be fixed to the hose near the tip of the hose, to enable the hose to bend when pulling one or more cables. [0061] The hose 50 may include multiple hose segments, each hose segment typically including at least one eye 52 per cable 51. This enables subsequent hose segments to be placed under an angle when pulling one or more of the cables, resulting in a bent hose 50.

[0062] Fig. 6 shows an alternative embodiment of how an actuation cable 61 may be guided along a hose 60. In this example, a cable 61 may be guided through eyes 62 spirally along the hose 60.

[0063] The steerable part of the hose may be bendable at multiple places, allowing more flexibility in reaching catalyst at different locations within the reactor. To enable multiple bends in a hose, cables may be fixed at different longitudinal positions to the hose. Fig. 8 shows an example wherein cables 71 are fixed to a hose 70 at a first longitudinal location 73. Pulling the cables 71 results in the hose being steered at the first longitudinal location 73. Other cables 74 are guided through the eyes to a lower longitudinal location (not shown) where the cables 74 are fixed to the hose 70 to enable the hose to be steered at the lower longitudinal location. The lower longitudinal location may be near the tip of the hose to enable the tip to be steered. Alternatively the lower longitudinal location may be similar to the first longitudinal location to enable a further bend in the hose.

[0064] Fig. 9 show an exemplary embodiment wherein a hose 80 is provided with pneumatic actuators 81 for bending the hose 80. In this embodiment the hose 80 may be steered by expanding and contracting one or more of the pneumatic actuators. In case the hose includes hose segments, each segment may include its own set of pneumatic actuators. Pneumatic actuators may be used in addition to or as an alternative to actuation cables. Different parts of the hose may be steerable using different types of actuators. For example a first part of the hose may use actuation cables while a second part of the hose may use pneumatic actuators.

[0065] In the exemplary embodiment of Fig. 3, a hoses assembly 30 is shown including two hoses 31, 32 each with ten segments 33 per hose (only one segment 33 has been identified in Fig. 3). In this example the first hose 31 may be an non-steerable hose and the second hose 32 may be a steerable hose.

[0066] In the exemplary embodiment of Fig. 4, a hoses assembly 40 is shown including three hoses 41-43. In this example the first hose 41 may be an non-steerable hose of a single segment. The first hose 41 may be implemented as a rigid pipe 44. The second hose 42 may be an non-steerable hose consisting of five segments 45 (only one segment 45 has been identified in Fig. 4). The third hose 43 may be a steerable hose consisting of five segments 46 (only one segment 46 has been identified in Fig. 4).

[0067] In an exemplary embodiment, to reach the lowest point in a reactor, eight 5 m hoses may be coupled to obtain a 40 m long assembly. This hoses assembly may include two steerable hoses positioned near the bottom of the reactor and six non-steerable hoses.

[0068] The catalyst 14 may contain clogged catalyst that can be almost as hard as stone. For removing this clogged catalyst, the catalyst unloading system may include an anti-clogging tool. The anti-clogging tool may be implemented as a hammer, a (possibly pneumatic) jackhammer, a rotating drill system, a whipping system or a combination thereof. The anti-clogging tool may be incorporated and integrated with the vacuum tubing.

[0069] Preferably, the anti-clogging tool can be positioned with an accuracy in the range of centimeters to the clogged catalyst. Preferably, the anti-clogging tool is capable of reaching the entire volume inside the reactor. Hereto, the tubing may be provided at the lower end, i.e. the end that collects the catalyst material, with an integrated anti- clogging tool or gripper to hold the anti-clogging tool. In case e.g. a hammer is used, the anti-clogging tool may be adapted to perform a swinging motion of the hammer.

[0070] Fig. 10 illustrates an anti-clogging tool 90, in the example of Fig. 10 in the form of a jackhammer, fixed near the tip of a hose. The anti-clogging tool 90 is typically operated from outside of the reactor. Hereto, conduits (not shown) connect the anti- clogging tool 90 to a control unit 16 outside of the reactor. These conduits are typically guided into the reactor through the same opening where the hose enters the reactor. The conduits may be guided along the hose or move freely from the hose.

[0071] The term "conduit" is used in a broad sense, and covers various kinds of elongate tubular structures that have relatively small cross-sections with respect to their lengths, and that are arranged for conveying matter and/or energy between source devices and destination devices. Exemplary conduits are formed by wires (e.g. single stranded) and cables (e.g. twisted strands, coaxial) comprising electrically conducting material for conveying electrical power and/or control or measurement signals, optical fibers (e.g. for conveying optical control and/or measurement signals), and fluid transport tubes (e.g. for conveying cooling fluids or air). [0072] A camera may be mounted on the vacuum tubing, preferably at the end of the flexible hose near the catalyst 14 to be removed, to give a clear image of the catalyst to the operator outside of the reactor 10. Another camera may be mounted higher up the vacuum tubing to show the bend of the flexible part of the vacuum tubing, to aid the operator outside of the reactor 10 in steering the flexible part of the tubing 21. The cameras may provide stereo vision images.

[0073] According to an aspect of the invention, the catalyst unloading system may include a stabilization system. The stabilization system may be used to stabilize the hoses assembly with respect to the reactor, for example by securing itself against the walls of the reactor. This enables for example the start of the steerable portion of the hoses assembly to be kept stable and the velocity of the end of the non-steerable portion to be kept substantially close to zero. An alternative solution for keeping the start of the steerable portion of the hoses assembly stable may use one or more sufficiently rigid pipes that precede the steerable hoses in the hoses assembly.

[0074] In an embodiment the stabilization system comprises a tripod system that may be lowered into the reactor. The tripod system may secure itself against the walls of the reactor by laterally extending the tripod arms towards the walls. Figs. 11-13 show various exemplary embodiments of tripod stabilization systems for stabilizing a hose.

[0075] Alternatively the stabilization system may include only one, two or more than three arms that may be secured to the walls of the reactor. Instead of using arms, the stabilization system may be realized in any other manner that enables the hoses assembly to be stabilized with respect to the reactor. An example hereof is a stabilization system using air thrusters to keep the hose, or at least the part of the hose that is to be stabilized, in place. In another example the actuation cables may be used in conjunction with a stabilization controller embedded in the control system 16 for actively compensating for movements of the part of the hose that is to be stabilized.

[0076] In the example of Fig. 11, a hose 100 may be stabilized by stabilization system 104. The part 101 of the hose 100 above the stabilization system 104 may be a non-steerable portion of the hose 100. The part 102 of the hose 100 below the stabilization system 104 may be a steerable portion of the hose 100. The stabilization system 104 may be positioned within the reactor by cables 103 or any other suitable means for guiding the stabilization system up and down the reactor. The stabilization system 104 may include telescopic stabilization arms 105 that can expand to secure the stabilization system 104 against the walls of the reactor.

[0077] In the example of Fig. 12, a hose 110 may be stabilized by stabilization system 114. The part 111 of the hose 110 above the stabilization system 114 may be a non-steerable portion of the hose 110. The part 112 of the hose 110 below the stabilization system 114 may be a steerable portion of the hose 110. The stabilization system 114 may be positioned within the reactor by cables 113 or any other suitable means for guiding the stabilization system up and down the reactor. The stabilization system 114 may include accordion like stabilization arms 105 that can unfold to secure the stabilization system 114 against the walls of the reactor.

[0078] In the example of Fig. 13, a hose 120 may be stabilized by stabilization system 124. The part 121 of the hose 120 above the stabilization system 124 may be a non-steerable portion of the hose 120. The part 122 of the hose 120 below the stabilization system 124 may be a steerable portion of the hose 120. The stabilization system 124 may be positioned within the reactor by cables 123 or any other suitable means for guiding the stabilization system up and down the reactor. The stabilization system 124 may include foldable stabilization arms 125 that can unfold to secure the stabilization system 124 against the walls of the reactor.

[0079] Additionally or alternatively the stabilization system may be used to allow a gripper that may be integrated with the stabilization system, to operate from a secured and stable base thereby enabling the gripper to perform operations like grasping and pulling a locking mechanism of a tray section to unlock it and then place the tray section to the side after which the unloading system may proceed to a lower bed.