EP1516908A1 - Coke drum with gate valve provided with pipe bridge - Google Patents

Abstract

To the outlet, inlet and/or access openings of a coking drum (3, 4), a pipe-bridging slide-plate valve is fitted as a shut-off valve (11). Valve closure plates (27, 28) have mutually-parallel, solid metal, sealing seats (24, 25) which seal against surfaces with hard cladding, made from wear- and corrosion-resistant material. The plates both move inside a spectacle casing. A pipe bridging section unites two pipe sections (22, 23) in the open position, one leading to the interior of the coking drum. The bridging section is a hollow circular cylinder with smooth internal surface. It is hard-plated internally to resist wear and corrosion, or is hardened. The valve closure plates are pressed onto the sealing surfaces in the closed position, by a ball-centered wedge section. A guide plate (45) associated with the valve closure plates is in constant metallic contact with the valve casing. The valve operating rod is sealed to slide in an out of the casing. A gas pressurization connection (44) is provided for the rod sealing chamber, this supplies sealing- or flushing gas. A drive actuator mounting is provided. Wear compensation is provided in the open position of the valve, by a wavy- or bellows-type type tube section, which fits around the pipe bridging section; it is fixed to one ring, but has axial freedom of motion w.r.t the other. An independent claim is included for the corresponding coking process.

Description

The present invention relates to a coking drum according to the preamble of claim 1 and a coking process, in particular for coking of residues from the vacuum distillation of crude oil, according to the preamble of claim 13.

In crude oil processing, increasing emphasis is being placed on heavy products, which are left over from the distillation of crude oil, to further process to lighter products. Thus, the production of heavy fuel oil is reduced and the production be increased by gasoline, diesel fuel and light fuel oil, without additional To process crude oil. The plants that are needed and after work different methods, called conversion systems. These transform heavy, long hydrocarbon molecules in light, shorter hydrocarbon molecules by splitting the long molecules. There are three such Cracking process: thermal, catalytic and hydrocracking. The optimal combination of procedures depends on several aspects, which include et al the nature of the crude and the desired products belong. The different cracking processes are based on different feed products from, wherein gas oil from the vacuum distillation as a feedstock for catalytic Crack plants and hydrocrackers and the residue from the vacuum distillation used in visbreakers or cokers as an input product.

The longest known and probably simplest cracking process is thermal Cracking. Hydrocarbon chains are split at high temperatures. The group of thermal cracking processes include the so-called visbreaking and the coking, in which carbon in solid form, so-called coke or Petroleum coke deposits.

There are three different methods of coking, namely the so-called Fluid Coken, the so-called Delayed Coken and the so-called Flexicoken. The most commonly used method is the Delayed Coken. In this Process is carried out at a pressure of about 30 bar, the feedstock, e.g. of the May be residue from the vacuum distillation, passed into an oven and at about Heated to 500 ° C. Due to these conditions, it flows through the furnace with very high Speed and then coked when entering a separate and from the oven with this coking chamber or coking drum connected via a pipeline, in which a chamber pressure of about 4 bar prevails.

In general, each oven is associated with at least two coking drums, each one of these chambers is in operation, while from the other the coke is removed. This can e.g. using water under high pressure the coking drum are cut out. The resulting from coking Light hydrocarbons pass from the coking chamber into a fractionating tower managed and processed there. The resulting petroleum coke becomes green coke and can either be sold after crumbling or continue be refined. The refinement happens in a calcination process, in burned at temperatures of 1200 ° C and more remaining oil components and Become coked. The resulting calcinate can then, for example for electrodes used in the aluminum industry come.

Each filled drum is cooled and the coke is removed from it. To First, water is passed into the drum to add to the resulting, hot coke cool. Then the drum is opened to the atmosphere by, depending on the design the coking chamber or drum, either only the bottom side or else the head of the drum or chamber is opened, so that the coke from the Drum cut out and fed to its further use can.

The process of opening the coking drum can be a source of danger for several reasons exhibit. The water that enters the drum to cool the coke The opening of the drum is very hot, which is not careful Handling of equipment due to escaping hot Water or water vapor, which is under pressure, can lead. Furthermore, loose Coke pieces fall out of the drum or load the opening mechanisms so that open them suddenly after unlocking, which also leads to injuries of the Operators can lead. Furthermore, the operator can also Dust, especially coke particles and also exposed to irritating or toxic gases be when the drums are opened.

To reduce the sources of danger for the operator, has been added passed over to no longer open the coking drums manually, but automatically by special, for example hydraulic lid actuation. Such Coke drum with an automatic opening mechanism is out of the WO 02/072729 A1. In the apparatus shown in this document To open coking drums is an automatically operable Slider, which ensures access to the coking drum in the open position, while the slide plate in closed position the coking drum completes against the atmosphere.

Disadvantage of the above-mentioned device is moderate security against an unwanted Escaping hot water or vapors and gases from the coking drum. Furthermore, it may be due to design disturbances, as coke or the like. On the guide rails of the slide, in particular on the coking chamber facing side of the guide rails, bake.

The object of the present invention is therefore to specify a coking drum, the closure works functionally and failsafe.

This object is achieved with respect to the device aspects by the features of the claim 1, with preferred developments and embodiments in the subclaims are described; in terms of process engineering aspects Reference is made to claim 13 and the claims dependent thereon.

An essential point of the invention is therefore that at an outlet and / or at or near an inlet and / or at an access opening of the coking drum a pipe bridge slide is arranged as a shut-off, the two shut-off plates having. This makes it possible the coking chamber with increased security seal. This is on the one hand a departure from the known closures with Bolting completed, on the other hand is also compared to the already known Slider closures made an improvement in two ways: to a is a double plate slide in this form provided for the first time, for second belongs the idea of the pipe bridge valve to the present invention.

In a preferred embodiment, the two shut-off plates to each other associated with parallel, full metallic sealing seats. These are characterized by an excellent Sealing effect.

In a further preferred embodiment, associated with the sealing seats Seal seats a wear and corrosion resistant hard armor on. Thereby the abrasive wear on the sealing seat surfaces is minimized, the maintenance intervals are extended, and cost savings are possible. The two Shut-off plates are preferably movable in a spectacle-shaped plate cage inserted, which makes the maintenance of the device according to the invention even easier.

Preferably, a pipe bridge is in an open position of the pipe bridge slider two pipe sockets connecting with each other, attached to the interior of the coking drum facing side and this opposite side of the Pipe bridge slide are attached, hollow cylindrical, in particular circular cylindrical educated. The pipe bridge has a smooth surface with one possible low roughness, thereby minimizing flow losses. In a Another embodiment, the pipe bridge on its inside a wear-resistant and corrosion-resistant hard armor or coating on, or is cured there. As a result, the abrasive wear on the pipe bridge is kept as low as possible.

The shut-off plates are preferably in the closed position via means of a Ball-centered wedge pieces pressed on sealing surfaces. This solution stands out also due to their low susceptibility to interference. A caking of coke or the like. on the guide rails of the shut-off plates is by pressing them in avoided the sealing position.

In a further preferred embodiment, a the shut-off plates associated Slider equipped with baffles that constantly contact the metal Have plate cage. This promotes the sealing effect and reduces abrasive wear.

Preferably, an actuating rod associated with the shut-off plates is fluid-tight inserted into the slide housing, wherein the slide housing a connection to Connection to a compressed gas source, in particular for connection to a flushing or sealing steam source is provided. Through the continuous introduction of Rinsing or sealing steam, the slide housing can be optimally cleaned, which the Störunanfälligkeit the coking drum according to the invention increased. Furthermore By applying the shut-off plates with pressure, the sealing effect strengthened. So the steam has a double function: on the one hand it serves Purification purposes, on the other hand, it causes an additional seal on two Sealing surfaces.

Does the pipe bridge valve of the coking chamber according to the invention additionally a Kompensatoreinheit, which offers the advantage that small column or Pass inaccuracies can be compensated in a simple manner, so the compressed gas connection offers further advantages. By applying the slider housing with compressed gas, preferably purging, the sealing effect of the Pipe bridge slider also reinforced in the open position of the slide become. The use of purging steam offers a cost savings potential because this for cleaning the housing interior and the guide plates and the plate cage is needed. The flushing steam thus serves on the one hand to improve the Sealing effect, on the other hand at the same time the cleaning of the closure device of Coking drum according to the invention.

In a preferred embodiment, hoods are with the slide housing Column attachment flanged to receive the drive. This embodiment is characterized by a particularly simple construction.

In a further embodiment, the pipe bridge slider, as already above mentions a compensator unit. The compensator unit offers the advantage that small gaps or Paßungenauigkeiten in a simple manner can be compensated, resulting in an excellent sealing function in each Situation leads.

The compensator comprises in a preferred embodiment a wavy curved Pipe section with a circumferentially extending indentation, wherein the wavy bent pipe section as an outer pipe section is coaxial over an inner tube section extending, which is fixed only with one of the two sealing rings is connected, while it is axially movable relative to the other sealing ring. Such an embodiment is characterized by a simple construction.

From a procedural point of view, it is an essential point of the invention that as Closing member for the coking chamber at least one pipe bridge slide with two shut-off plates is used. The advantages of the method according to the invention thus result analogously to the above description of the device claims.

Served in a preferred embodiment of the method according to the invention the pressure prevailing inside the drum when opening the coking drum, around the the interior of the drum facing shut-off to press its associated sealing seat. This reduces the effort required is to open a coking drum or its shut-off.

Fig. 1

schematisch den Aufbau einer Verkokungsanlage,

Fig. 2

das Absperrglied einer Verkokungsanlage in Schnittansicht,

Fig. 3

das Absperrglied einer Verkokungsanlage mit teilweise weggebrochenem Gehäuse,

Fig. 4

eine Schnittansicht entlang durch das Absperrglied der Fig. 2 entlang der Achse X-X,

Fig. 5

eine Detailansicht des Ausschnitts, der in Fig. 2 mit Y gekennzeichnet ist,

Fig. 6

eine Teilansicht einer zweiten Ausführungsform eines Absperrgliedes der Verkokungstrommel, und

Fig. 7

das Absperrglied gemäß Fig. 6 im Schnitt längs der Linie II-II in Fig. 6.

The invention will now be described by way of example and with reference to the accompanying drawings in view of further advantages and features. The drawings show in:

Fig. 1

schematically the construction of a coking plant,

Fig. 2

the shut-off member of a coking plant in sectional view,

Fig. 3

the shut-off of a coking plant with partially broken housing,

Fig. 4

a sectional view along the obturator of FIG. 2 along the axis XX,

Fig. 5

a detailed view of the section, which is marked in Fig. 2 with Y,

Fig. 6

a partial view of a second embodiment of a shut-off of the coking drum, and

Fig. 7

6 in section along the line II-II in Fig. 6.

Fig. 1 is a schematic representation of a coking plant. This consists of: a furnace 1, via a line 2 with the residues from the vacuum distillation is fed by crude oil; two coking chambers 3, 4, via a pipe 5 are fed with the oven-heated residues from the vacuum distillation; a conveyor belt 6, with which the coke produced in the coking chambers is transported further; and a Fraktionierkolonne 7, in which the coking process in the coking chambers 3 and 4 resulting gases, the fractionation 7 are fed via a line 8, are fractionated.

Furthermore, the coking plant has a furnace 9 with a turntable, in which at least Parts of the coke recovered in the coking chamber can be calcined. The heavy residues that remain in the Fraktionierkolonne 7 are over a Outlet 12 and a line 10 back into the line 2 and thus again the Coking process supplied. At this point it should be mentioned that the coking 3, 4 both on only one side for the removal of coke accumulated therein can be opened, as well as on two sides, so at a head and a foot end, so as to ensure easier removal. For this purpose, a shut-off 11 and the coke is then removed using suitable equipment.

In Figures 2, 3 and 4, a first embodiment of the shut-off member 11 for the coking chambers 3, 4 shown in different views. In addition is in Fig. 5 is given a detailed view of the marked in Fig. 2 with Y area.

The slider shown has a slide housing 21 with two pipe sockets 22 and 23 and two housing sealing seats 24 and 25, between which two shut-off plates 27, 28 are mounted displaceably with sealing rings 29, 30. The two shut-off plates 27 and 28 are against the housing sealing seats 24 and 25 by means of a Spreizorgan acting inner wedge 31 pressed, which at the end of an actuating rod 32 sits and is firmly connected to this. The shut-off plates 27, 28 are for this purpose by the inner wedge 31, which is centered by means of a ball, after a "Wedge-in-wedge principle" spreadable. This construction ensures that the slider easy to operate even under the most difficult thermal and dynamic conditions is. Jamming is not possible, since the inner wedge 31 is a non-self-locking Form has.

Below or next to the slide plate 26, a pipe bridge 33 is arranged, the two sealing rings 34, 35 has. The pipe bridge 33 is formed as a hollow cylinder, i.e. In particular, it has no corrugations on its inside, so that do not form any resulting flow losses (see also Fig. 4).

In Figures 2 and 3, the slider is shown in the closed position. The slide housing 21 is formed fluid-tight to the outside, so that in the interior 43 of the valve body a gas pressure is adjustable, which can be greater than the pressure in the Slide through. For this reason, the actuating rod 32 is fluid-tight in the slider housing 21 is inserted. On slide housing 21 is a connection 44 for Connection to a (not shown) compressed gas source, in particular a flushing steam source, arranged. By a continuous flushing of the interior 43 of the Slider housing will clogging of dirt and a resulting Disturbance of the coking 3.4 largely avoided. The sealing surfaces the sealing rings 34, 35 on the one hand and the housing sealing seats 24, 25 on the other are each formed extending parallel to the slide actuating direction. To increase the wear resistance, the aforementioned are known per se Hardened or armored way.

The shut-off plates 27, 28 are in a spectacle-shaped plate cage (in FIGS not shown), which ensures their holder, movably inserted. This Plate cage is guided between baffle plates 45, whereby an ingress of contaminants is avoided in the housing.

By inspection opening 49, 50 in the form of a blind flange, it is possible, in particular to the pipe bridge 33 easy access for observation purposes o.ä. to obtain.

Via a coolant inlet 51, the actuating rod 32, in particular at its from the housing projecting end, to be cooled. This is preferably done by cold air or cold gases. At this point it should be mentioned that a liquid cooling is conceivable.

In Fig. 4, the shut-off member 11 is in its open position along a section line X-X of Fig. 2 shown. Here it is clear that the pipe bridge 33rd the pipe socket 22, 23 connects without rejuvenation of the cross section. In addition to the sealing rings 34, 35 and the housing sealing seat 24, 25, it is recommended that the entire inner side of the pipe bridge 33 to harden or to armor, thus abrasive Prevent wear.

The section marked Y in FIG. 2 is again shown enlarged in FIG. 5. In this one can clearly see a rinsing and sealing steam channel 53, at a connection piece 52 (see Fig. 3) with a rinsing and sealing vapor source connected is. Furthermore, it can be seen in Fig. 5, a cutting edge 54, the Elimination of adherent coke is used. This is hard-shelled.

In the figures 6 and 7, a second embodiment of the obturator 11 of Coking chamber 3, 4 shown. Same parts or parts with the same functionality have the same reference numerals as the obturator according to the first Embodiment (FIGS. 2 to 5). They will therefore not continue in the following described.

The pipe bridge 33 of the shut-off member 11 according to the second embodiment sets itself from the sealing rings 34 and 35 and one connecting the sealing rings together Compensator 36 together. The compensator 36 consists of an inner Pipe section 37 and a coaxially extending outer pipe section 38, wherein the outer pipe section 38 via ring welds 39, 40 with both Sealing rings 34, 35 is firmly connected.

Further, the outer pipe section 38 has a circumferentially extending Wave or indentation 41. The inner tube section 37 is hollow cylindrical, i. formed without a shaft, so that analogous to the shut-off member 11 according to the first embodiment no trim losses can occur. Furthermore, according to the second embodiment of the inner pipe section with only one of the two sealing rings, namely here the sealing ring 35, firmly connected via a ring weld 42. Compared to the other sealing ring 34, the inner tube section 37 is axially movable, wherein the axial clearance between the sealing ring 34 and the inner pipe section 37 is between about 1.0 mm to about 5.0 mm.

The arrangement of the inner pipe section 36 with respect to the two sealing rings 34th and 35 is such that the inner surface of the pipe section 36 with the inner surfaces the sealing rings 34, 35 are aligned, so that a virtually continuous flow passage is created in the open position of the slider. In the figures 6 and FIG. 7 shows the slide analogously to FIGS. 2 and 3, each in the closed position. Also in the second embodiment, the slider housing 21 is after formed on the outside fluid-tight, so that within the slide housing analogous to first embodiment, a gas pressure is adjustable.

The circumferential indentation 41 of the outer tube section 38 extends to close to the outer surface of the inner tube section 37 so that the inside of the housing 43 prevailing gas pressure on the indentation 41 on the sealing rings 34, 35th under axial spread of the same is fully effective. The axial spread of the sealing rings 34, 35 is on the one hand by the indentation 41 and the other by the Axial clearance between the inner pipe section 37 and one of the two sealing rings, here sealing ring 34, possible.

The pipe bridge 33 is therefore by the two sealing rings 34, 35 on the one hand and arranged between these, serving as a compensator 36 inner and outer pipe sections 37, 38 on the other hand, forming a ring box 46th limited. This ring box 46 and the annulus between inner and outer Pipe section 37 and 38 is with a heat-insulating material, in particular Glass wool, rock wool or the like. Completed.

The filling has not only a heat-insulating purpose, but also the Purpose, the penetration of flow medium in said annulus between inner and outer pipe section to prevent. Adding the annulus with Flow medium or gas flow with dust and dirt particles or similar deposits would after prolonged use the effect of the compensator 36 disturb or impair. Insofar, the aforementioned execution a double function.

In the context of a known coking process, the above in the Description of Fig. 1 is explained in more detail, brings the use of a pipe bridge slide a special sealing aspect with it. The introduction of flushing steam or the resulting action on the interior 43 of the valve body with pressure (sealing steam) provides optimal sealing of the Coking drum 3, 4, in which the coking takes place at the respective time, for sure. In addition to the introduction of a wedge between the two shut-off plates 27, 28th These are additionally pressurized, resulting in increased security guaranteed.

The respectively filled coking drum 3, 4, however, is cooled, and the coke is removed from it. For this purpose, water is first passed into the coking drum 3, 4, to cool the resulting, hot coke. Then the coking drum 3, 4 open to the atmosphere, where in the interior of the coking drum 3, 4 prevailing pressure facing the interior shut-off plate pushes away from the valve seat and thus necessary to open the pipe bridge slide Reduced effort. If you go after opening the coking drum 3, 4 again rinsing or sealing vapor into the interior 43 of the valve body, so On the one hand, the housing and the components arranged in the housing continuously cleaned, on the other hand is due to the increased sealing effect of Pipe bridge an intrusion of dust when emptying the Coking drum 3, 4 arises to an increased extent, prevented in the housing.

Although the invention based on embodiments with a fixed feature combination is described, but it also includes the possible further advantageous Combinations of these characteristics, in particular, but not exhaustively, are given by the dependent claims. All in the registration documents disclosed features are claimed as essential to the invention, as far as they individually or in combination with the prior art.

Reference numerals:

1

oven

2

management

3

coking chamber

4

coking chamber

5

management

6

conveyor belt

7

fractionating

8th

management

9

oven

10

management

11

shutoff

12

outlet

21

slide housing

22

pipe socket

23

pipe socket

24

Housing sealing seat

25

Housing sealing seat

26

slide plate

27

shut-off

28

shut-off

29

seal

30

seal

32

actuating rod

33

Rohrbrücke

34

seal

35

seal

36

compensator

37

inner pipe section

38

outer tube section

39

ring weld

40

ring weld

41

wave

42

ring weld

43

Inside of the valve body

44

Connection

45

circuit board

46

ring box

49

maintenance closure

50

maintenance closure

51

Coolant inlet

52

connecting branch

53

Flushing and sealing steam channel

54

cutting edge

Claims (16)

Coking drum (3, 4), in particular for the production of petroleum coke, which has an approximately cylindrical base body, at least one inlet and an outlet and a further access opening,
characterized in that
at the outlet and / or at or near the inlet and / or at the access opening a pipe bridge slider is arranged as a shut-off member (11) having two shut-off plates (27, 28). Coking drum (3, 4) according to claim 1,
characterized in that
the two shut-off plates (27, 28) are associated with each other parallel, fully metallic sealing seats (24, 25). Coking drum (3, 4) according to claim 1 or 2,
characterized in that
the sealing seats (24, 25) associated with sealing seats have a wear and corrosion resistant hard armor. Coking drum (3, 4) according to one of the preceding claims,
characterized in that
both shut-off plates (27, 28) are movably inserted in a spectacle-shaped plate cage. Coking drum (3, 4) according to one of the preceding claims,
characterized in that
a pipe bridge (33) which in an open position of the pipe bridge slide (11) connects two pipe sockets (22, 23) to one another on the side facing the interior of the coking drum (3, 4) and the opposite side of the pipe bridge slider (11 ) are mounted as a hollow cylinder, in particular circular cylinder, is formed with a smooth surface. Coking drum (3, 4) according to one of the preceding claims,
characterized in that
the pipe bridge (33) on its inside has a wear and corrosion resistant hard armor or coating, or is cured. Coking drum (3, 4) according to one of the preceding claims,
characterized in that
the shut-off plates (27, 28) in the closed position are pressed onto sealing surfaces by means of a ball-centered wedge pieces. Coking drum (3, 4) according to one of the preceding claims,
characterized in that
a slide associated with the shut-off plates (27, 28) is provided with guide plates (45) which constantly have metallic contact with the plate cage. Coking drum (3, 4) according to one of the preceding claims,
characterized in that
a control rod (32) associated with the shut-off plates (27, 28) is inserted in a fluid-tight manner into the valve body (21), and that at least one pipe bridge valve (11) on the valve body (21) has a connection (44) for connection to a source of compressed gas, in particular flushing - Provided is provided via the compressed gas for flushing or for additional sealing of the valve body. Coking drum (3, 4) according to one of the preceding claims,
characterized in that
to the slide housing (21) hoods are flanged with a column attachment for receiving a drive. Coking drum (3, 4) according to one of the preceding claims,
characterized in that
the pipe bridge slide (11) has a compensator (36) which compensates for gaps and fit inaccuracies in an open position of the pipe bridge slide (11). Coking drum (3, 4) according to claim 9,
characterized in that
the compensator (36) comprises a wavy curved pipe section (38) with a recess extending over the circumference (41), wherein the wavy bent pipe section (38) extends as an outer pipe section coaxially over an inner pipe section (37) which only with one of the two sealing rings is firmly connected, while it is axially movable relative to the other sealing ring. Coking process, in particular for coking residues from the vacuum distillation of crude oil, in which the material to be coagulated is heated in an oven and fed to a coking drum (3, 4), in which the actual coking process takes place,
characterized in that
on the coking drum (3,4) at least as a shut-off member (11) a pipe bridge slide with two shut-off plates (27, 28) is used. Coking method according to claim 13,
characterized in that
for additional sealing of the coking drum (3,4) at least one pipe bridge slide (11) with pressurized gas, in particular rinsing or sealing steam, is applied / are. Coking method according to claim 13 or 14,
characterized in that
in the interior (43) of a slide housing (21) a gas pressure is set, in particular in a closed position of the shut-off plates (27, 28), which is greater than the pressure prevailing in the coking drum (3, 4). Coking method according to one of claims 13 to 15,
characterized in that
when opening the or each pipe bridge slide (11) in the interior of the coking drum (3, 4) prevailing pressure for pushing away the interior facing the shut-off plate from the valve seat and thus the force required to open the Absperrgliedes (11) force is reduced.

Images