JPS5844407B2 - Rose sawtail element - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for removing powder impurities from a fluid stream entering a bed of bulk solid elements, and more particularly, for removing impurities from a hydrocarbon stream entering a bed of granular catalyst. Relating to an improved design of a removal basket.

Any process that involves directing a flow of fluid material consisting of a gas, liquid or mixture of gas and liquid through a bed of bulk solid elements or particulate material, such as a bed of particulate catalyst in a chemical reaction zone or reactor. The cycle life of the bed itself is governed by the amount of impurities entrained in the fluid stream.

Powdered impurities are filtered out of the fluid stream by the layer of material in the bed into which the fluid stream enters, so that if a sufficiently large amount of these powdered impurities accumulates at or near the surface of the bed into which the fluid stream enters, The pressure drop across the floor increases to such an extent that the floor is no longer able to do the work it is allowed to do.

For this reason, reactors and the like having beds have to be shut down.

A grid of cylindrical wire mesh containers called "trash baskets" placed in the bed with their open ends at or near the surface of the granular catalyst bed or other bed into which the fluid stream enters. It has been proposed to solve this problem and extend the cycle life of the floor by doing so.

In this way, the fluid flow first takes the path of least resistance and enters the catalyst bed through a cylindrical wire mesh vessel, so that solid impurities entrained in the fluid are filtered out of the fluid, for example by wire mesh. be done.

Only after a significant amount of impurities has accumulated in the vicinity of the wire mesh containers does the pressure drop across these wire mesh containers reduce the flow of fluid through the superficial, or bare surface, of the catalyst bed between the wire mesh containers. increases to the point where it essentially seeks entry into the catalyst bed.

However, since the accumulated impurities first accumulate near the bottom of the cylindrical wire mesh container, the accumulated impurities tend to be filtered out radially from the bottom of the wire mesh container, relative to the fluid flow through the catalyst bed. , which has the effect of closing the entire cross section of the catalyst bed.

For this reason, neither the vertical side walls of the wire mesh container, which still remain substantially free of initial impurities, nor the surface area of the catalyst bed free from the wire mesh container are effectively utilized as a fluid flow entry site.

Therefore, if you use the wire mesh container that has been proposed so far,
Although it extends the cycle life of the catalyst bed to some extent, it still leaves a significant portion of the catalyst bed that cannot be effectively utilized, for example, to filter impurities from a fluid stream.

Accordingly, one of the objects of the present invention is to provide an improved apparatus for removing powder impurities from a fluid stream entering a bed of bulk solid elements.

Another object of the present invention is to provide an improved device for insertion into a bed of solid elements which allows maximum utilization of the bed of loose solid elements for removing entrained powder impurities from an incoming fluid stream. It is.

Yet another object of the present invention is to provide an improved device for contacting a fluid with a bed of bulk solid elements in which the cycle life of the bed of bulk solid elements is significantly increased compared to the life of known devices of the same type. .

Yet another object of the present invention is to provide a method for removing powdery impurities from a fluid stream entering a bed of bulk solid elements that significantly increases the cycle life of the bed.

In order to achieve the aforementioned objects, the present invention generally has its longitudinal axis coincident with the direction of fluid flow and a significant portion of its total length, such as a large portion, preferably at least about An elongated hollow basket part extending 80% through a bed of bulk solid elements provides a device for removing powdered impurities from a fluid stream entering the bed of bulk solid elements.

The basket part consists of a side wall and a bottom wall, and the bottom wall and the lower part of the adjacent side wall have a mesh structure through which fluid passes, while the lower part of the side wall adjacent to the open end facing the bottom of the basket part has a gap. and is of substantially, preferably completely fluid-tight construction.

The upper fluid impermeable portion of the sidewall has a length sufficient to extend below the surface of the bed of loose solid elements from which a substantial portion of the device extends.

This top portion of the basket component includes a device for at least partially restraining the flow of fluid entering the basket component, typically one or more orifices in the solid top wall of the basket component.

The device also has a cross-section larger than the basket component and is placed in a nested hole relationship with the top of the basket component to provide a means for temporarily reversing the direction of fluid flow before it enters the basket component. Includes broken lid parts.

The invention also provides a chamber, a bed of bulk solid elements contained in the chamber, such as a bed of catalyst particles, a fluid stream inlet and outlet device, and at least one of the aforementioned types for removing powdered impurities from the fluid stream. Consisting of one device,
An apparatus is provided for contacting a fluid stream with a bed of loose solid elements.

In a preferred embodiment, the fluid inlet device is positioned above the fluid outlet device so that fluid passes through the bed in a generally downward direction.

The present invention also provides an improved method for removing powdered impurities from a fluid stream entering a bed of bulk solid elements.

In this method, one of the solid element beds has at least one elongated hollow basket part whose longitudinal axis coincides with the direction of fluid flow and a substantial portion of its entire length extends into the solid element bed. The fluid stream is preferably directed in a generally downward direction.

The basket component comprises a side wall and a bottom wall, the bottom wall and the adjacent lower part of the side wall forming a fluid-permeable mesh structure, and the upper part of the side wall having a substantially, preferably completely fluid-tight structure. ing.

At least a portion of the fluid-tight upper portion of the side wall extends into the floor.

Fluid flow is initially at least partially restrained from entering each basket component, such that fluid flow enters the floor from the bare surface of the floor adjacent to the installed basket component, and this This exposed surface removes powdered impurities from the fluid stream until the pressure drop through which it flows into the bed is greater than or equal to the pressure drop through each basket part.

Other objects and advantages of the invention will become apparent from the following detailed description of the invention, taken in conjunction with the accompanying drawings.

The present invention increases the cycle life of a bed of discrete solid elements comprising catalyst particles to be contacted by flowing the fluid temperature, preferably in a generally downward direction, while carrying out any of the many known chemical reactions. It is particularly advantageous for applications relating to

For example, the "trash basket" device of the present invention may be used in a catalytic reactor utilized to contact a downwardly flowing stream of liquid hydrocarbon feed mixed with gaseous hydrogen with a conventional hydrogen reforming catalyst or reforming catalyst. can be used.

Although the present invention will be described below with reference to a specific embodiment involving a bed of bulk solid elements of catalytic material of the type described above, the principles of the invention are such that a fluid stream contacts a bed of bulk granules. It should be understood that other methods may be used as well.

Referring now to the drawings, FIG. 1 includes a packed bed of pulverized catalytic material 12 and a relatively thin layer of essentially non-catalytically active alumina spheres 14 covering its surface. A common catalytic reactor is exemplified.

One of the functions of the alumina spheres 140 is to help immobilize the bed of catalyst material 120.

A plurality of "trash basket" pieces 16 are equidistantly spaced across the entire surface of the alumina sphere 14.

The arrangement can be seen more clearly with reference to FIG.

Basket part 16 is inserted into catalyst material 12;
A significant portion of its length extends into the catalytic material, with a slightly shorter portion extending over the surface of the catalytic material and the overlying layer of alumina spheres 140.

From FIG. 3, the structure of the basket part 16 can be seen in more detail.

Each basket part 16 is defined by side walls 20 and bottom walls 23 extending essentially from top to bottom, with the top of each basket part 16 remaining generally open.

The lower portion 21 of the side wall 200, which extends over a substantial portion of the length of each basket component 16, is fabricated from a fluid permeable mesh type material, such as woven wire or the like.

The size of the openings in the mesh is generally not a problem as long as it is smaller than the average particle size of the bulk solid material forming the catalyst bed in contact with the mesh.

The bottom wall 23 is likewise made of this fluid-permeable mesh material.

On the other hand, the upper part 22 of the side wall 20 of each basket part 16 extends from the top of the basket part 16 to the catalyst bed 12 and the alumina spheres 1.
4 extends downwardly along sidewall 20 to a point well below the surface of sidewall 20 so that fluid entering the exposed surface of alumina spheres 14 interposed between each basket component 16 will flow along sidewall 20.
0 basket parts 16 spaced through the lower part 21
Do not shorten to.

In a basic embodiment of the present invention, the upper end of each basket part 16 is configured to reduce the flow of fluid through the basket part.
Also, a device is attached to partially restrain it.

In the illustrated embodiment, the restraint device includes a continuous end wall 24 located at the upper end of the basket component 16;
It has one orifice passing through it.

Obviously, a plurality of such orifices can be provided, or a continuous part can be provided which only partially covers the upper end of the basket part 16.

Further, a device may be provided at the upper end of the basket component 16 to adjust the degree of opening to be kept open as a fluid passage.

In a further preferred embodiment of the invention, each basket part is additionally provided with a device for reversing the direction of the fluid flow just before it enters the basket part 16.

In FIGS. 3 and 4, the aforementioned fluid flow reversal creates a generally inverted U-shaped closure component 30 having a continuous end wall 32 and a downwardly depending continuous wall or flange 34. This is done by providing.

The lid part 30 has a larger cross section than the basket part 16 and fits into the nesting hole with the basket part so that the lower end of the downwardly depending wall 34 extends below the height of the upper end of the side wall 22 of the basket part 16. will be installed.

A continuous end wall 2 is provided to secure the lid part 30 in place.
A plurality of spacing parts 36 are provided at intervals around the circumference of 4.

Lid part 30 and basket part 1 by reversing the direction of +-3 fluid flow for fluid to flow into the basket part.
It must be passed upwardly through the annular portion 38 formed between the side wall 22 of 6 and the side wall 22 of 6.

This reversal of direction is accomplished by initially depositing and eliminating large particles entrained in the fluid stream.

In operation, a fluid stream, such as a stream that is almost entirely liquid, a mixed gas-liquid stream, or a stream that is preferably almost entirely gas, enters the reactor through the inlet port 11 of the contact reactor and is introduced into the catalyst material 12. Directed downwards.

Because the opening in each basket part 16 is partially restricted, fluid flow has a lower pressure drop entering the catalyst material 12 through the exposed surface of the alumina spheres 14 than through the basket part 16.

Thus, fluid flow initially enters the catalyst material 12 through the exposed direction of the alumina spheres 14.

Alumina bulb 1 on or near the exposed surface of alumina bulb 14
4 and catalytic material 12 are initially uncontaminated and thus serve to remove entrained powder impurities from the fluid stream during the initial stages of operation.

When the reactor 10 is operated for a certain period of time, the alumina spheres 14
Portions of the alumina bulbs 14 and catalyst material 12 at or near the exposed areas begin to become contaminated with accumulated impurities, resulting in a greater pressure drop as the fluid stream passes through these portions.

Eventually this pressure drop will cause the fluid flow to reach the basket part 16.
equal to, and then greater than, the pressure drop as it flows through.

At this time, fluid flow is preferentially directed to the basket component 16.
The powdered impurities that are entrained in the fluid stream flow along the portion of the catalytic material 120 surrounding the lower part 21 and bottom wall 23 of the networked sidewalls and along the basket part 1.
6 itself, in particular the wire mesh of the bottom wall of the basket part 16.

Thus, both the top of the catalytic material 12 and the inner surface of the basket part 16 itself are effectively used to remove entrained powder impurities from the fluid stream, thereby reducing the cycle life of the catalytic material 12. Increase to the maximum.

In the foregoing more preferred embodiment of the present invention, in which a lid part 30 is provided over each basket part 16, the operation is essentially the same as described above, but with the exception that large sized particles of impurities entrained in the fluid stream are removed. particles tend to deposit at the point where the fluid stream is reversed just before it enters the basket component, thus providing an additional means of removing impurities from the fluid stream and reducing the effective cycle of the catalytic material 12. The difference is that it can extend lifespan even more effectively.

As mentioned above, the improved "trash basket" design of the present invention is most preferably used in the field of catalytic reactors;
Generally any conventional reactor can be used.

A typical reactor of this type is approximately 0.046 m (0.5 f
t2) or less to approximately 15.8m” (170f
t2) or higher, preferably 0.465
Preferably circular cross-sectional area of 5 to 150 ft2 and about 1.52 m or less to 38 m
．． Within the range of 1 m (125 ft) or more, preferably about 3.05-21.3 m (10-70 ft)
It has a length of

The particles used to form the bed in this type of reactor may be of any suitable geometry, e.g. spherical, cylindrical, granular,
It may be in the form of a tablet, irregular shape or other shape.

Preferably the maximum linear dimension of the particles is about 3% of the diameter of the reactor.
It is better not to exceed.

As a representative example, catalyst particles of this type have a minimum dimension of at least about 0.25 mm (0.01 inch) and about 12.7 mm (1/2 inch) or 25.4 mm (1 inch).
inches) or larger.

The "trash basket" device of the present invention is used for oil refining,
It is particularly useful when used in reactor systems for catalytic chemical conversion of hydrocarbons, such as those involved in petrochemical processing.

Conventional and well-known hydrocarbon chemical reactions that are facilitated by catalysts and for which the apparatus and methods of the present invention may be used include oxidation, hydrosulfidation, hydrocracking, cracking, reforming, hydrogenation, polymerization, etc. , alkylation, isomerization, disproportionation, etc.

Typical operating conditions and catalyst compositions used in each catalytic reaction system are well known to those skilled in the art and can be varied to meet the requirements of the particular hydrocarbon processing process.

For this reason, an exhaustive list of reaction conditions and catalyst compositions is omitted here.

However, by way of example, a typical example of a hydrocarbon hydrosulfurization catalyst includes a support, any one or more transition metals known to catalyze the hydrosulfurization reaction, and a metal oxidation catalyst. It consists of metal salts, metal sulfides, and other metal salts.

A typical hydrocarbon reforming catalyst consists of at least one platinum group metal supported on a support.

An example of a typical hydrocracking catalyst is a crystalline metal aluminosilicate zeolite containing a platinum group metal, such as platinum or palladium, deposited on or in composition with a zeolite.

The hydrogenation catalyst comprises at least one metal from Group I of the Periodic Table, such as nickel, cobalt, iron, or a metal from the platinum group, such as palladium, platinum, iridium or ruthenium, supported on a suitable support. It can be a mixture.

Suitable carriers or supports for these catalysts can be materials such as silica, alumina, zirconium oxide, titanium oxide, magnesia, boron oxide, silica-alumina, silica-magnesia, acid clay, halogenated alumina, etc. .

Mixtures of one or more of these materials can also be used in these catalysts.

A representative embodiment of the invention uses a reactor having an internal diameter of 3.96 m (13 feet) and a length of 15.2 m (50 feet).

The reactor is equipped with a bed of catalyst particles having a particle size of 1.6 mm (1716 inches) and is topped with a 6 inch thick layer of alumina spheres having a particle size of 19 mm (3/4 inch).

Fifty-five "trash basket" devices according to the invention having an equidistant cylindrical shape with a center-to-center spacing of 508 mm (20 inches) and a diameter of 203 mm (8 inches) are evenly distributed.

The total length of each basket part is 1651mm (65 inches)
The total length of the lower fluid-permeable mesh portion of the basket component is 1219 mm (48 inches), and the upper fluid-impermeable wall portion is 432 mm (1 inch).

Each basket part is approximately 1524m from the top of the alumina sphere.
m (60 inches) downwardly so that the fluid-tight continuous top wall portion of each basket component extends approximately 305 mm (12 inches) below this surface.

The required pressure drop when passing through the basket part is approximately 2”/2” diameter left open for fluid passage.
This is achieved by providing the basket component with an annular continuous top wall having a 2 inch orifice.

In the most preferred embodiment, each basket part has a diameter of 2
A circular lid piece is provided having side walls that are 10 inches wide and suspend downwardly by 3 inches.

25mm between the wall of the lid part and the side wall of the basket part (
To provide a nested overlap of 1 inch), the lid piece should be approximately 511n7IL(
2 inches) apart and placed on top.

Accordingly, the present invention provides an improved design of a "trash basket" apparatus for use in apparatus and methods for contacting a fluid stream with a bed of bulk solid elements, such as a catalyst. It can be seen that the effective cycle life of the bed is significantly extended because the portion at or near the surface of the bed that enters the particle bed and removes powdery impurities entrained, for example, from the fluid stream, can be more effectively utilized.

Although the invention has been described and pointed out with reference to only one preferred embodiment thereof, without departing from the spirit of the invention,
It will be appreciated that various minor modifications, changes and additions may be made to the "trash basket" device designed as described above.

It is the intention, therefore, to be limited only by the scope of the claims appended hereto.

Embodiments of the invention are summarized as follows.

(1) at least one in which the flow restraint device occupies a substantial portion of the opening formed by the fluid-impermeable sidewall;
Claim 1 consisting of a solid part that does not allow fluid to pass through.
The device described.

2. The device of claim 1, wherein the flow equalizing device comprises a solid end wall of the basket part including at least one orifice.

3. The apparatus of claim 1 further comprising a device for temporarily reversing the direction of fluid flow before the fluid enters the basket component.

(4) The device for reversing the direction of fluid flow comprises a lid part having a larger cross-section than the basket part and placed in a telescoping relationship with the top of the basket part.
The device described.

(5) The device according to claim 1, wherein the basket component has a circular cross-sectional shape.

(6) a chamber, a bed of loose solid elements contained within the chamber, a fluid inlet, a fluid outlet located below the inlet, and at least one for removing powdered impurities from the fluid;
An apparatus for contacting a fluid with a bed of loose solid elements, comprising the apparatus of claim 1.

7. The apparatus of claim 1, wherein the bed of discrete solid elements comprises a bed of catalyst particles.

(8) The method of claim 2, wherein the bed of bulk solid elements comprises a bed of catalyst particles.

9. The method of claim 2, wherein the fluid stream is gaseous in nature.

10. The method of claim 2 further comprising the step of removing large particles of impurities by temporarily reversing the flow of the fluid stream just before entering each basket part.

(11) The above (8), wherein the catalyst is a hydrocarbon conversion catalyst.
) method described.

(12) The catalyst performs at least one type of carbonization selected from the group consisting of hydrocarbon oxidation, hydrogen sulfidation, hydrogen cracking, decomposition, reforming, hydrogenation, polymerization, alkylation, isomerization, and disproportionation. The method according to (8) above, which is a hydrocarbon conversion catalyst used to promote a hydrogen chemical reaction.

(13) The method according to the above item 0υ, wherein the fluid stream is essentially gaseous.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway front view of a reactor and a bed of loose solid elements having one of several embodiments of an impurity removal apparatus according to the invention, and FIG. This is a top view. 3 is a cross-sectional view of an apparatus of the present invention for removing powdered impurities from a fluid stream, taken along line 3--3 of FIG. 1, and FIG. 4 is a cross-sectional view taken along line 4--4 of FIG. It is a diagram. Each reference number in the figure has the following meaning. 10: reactor, 11: fluid inlet device, 12: catalyst material, 14: alumina sphere, 16: basket component, 20: side wall, 23: bottom wall, 24: end wall, 26: orifice, 3
0: Lid parts.

Claims (1)

Claims: 1. A method for removing powdered impurities from a fluid stream entering a bed of bulk solid elements, the method comprising: directing the fluid flow in a generally downward direction toward one surface of the solid element bed having at least one elongated hollow basket part extending into the bulk solid element bed; and by initially partially restraining the flow of fluid entering each basket part, the solid elements A method for removing powdery impurities from a fluid stream entering a bed of bulk solid elements, the method comprising removing the powdery impurities from the fluid stream at or near a surface portion of the bed. 2 Apparatus for removing powdered impurities from a fluid stream entering a bed of bulk solid elements, the apparatus comprising a side wall and a bottom wall, the bottom wall and the adjacent lower part of the side wall forming a fluid-permeable network structure. None, the upper part of the side wall adjacent the top opposite the bottom wall is of substantially fluid-impermeable construction, and the upper part of the side wall is of substantially fluid-impermeable construction and is sufficiently large that this fluid-impermeable portion extends below the surface of the bulk solid element bed. an elongated hollow basket part having a length, the longitudinal axis of which is aligned generally with the direction of fluid flow, and arranged such that a substantial portion of its length extends in the bed of solid elements; removing powdery impurities from a fluid stream entering a bed of bulk solid elements, the method comprising: a basket part having a filtered structure; and a device adjacent the top of the basket part for at least partially restraining the flow of fluid entering the basket part; device to do.