DE10137284B4 - Process for dismantling a process engineering apparatus - Google Patents

Abstract

Process for the disassembly of a process engineering apparatus (6) consisting of a housing (12) and internals (15) arranged therein, e.g. B. a shell-and-tube heat exchanger, with the following steps:
a) filling a processable or flowable, solidifiable mass in the housing (12) such that the mass distributed around the internals (15) in the housing (12),
b) allowing the filled mass to solidify,
c) cutting the apparatus (6) into individual elements of easily transportable size,
d) softening the mass contained in the individual elements, preferably by their renewed transfer into the sprayable or flowable state.

Description

The The invention relates to a method for disassembling one of a housing and arranged internals existing procedural apparatus, z. B. a tube bundle heat exchanger.

Not more usable or otherwise no longer needed Process engineering apparatus are, as far as possible, dismantled by disassembly into their original items. In that sense can be in contrast to a construction of a "deconstruction" of the apparatus speak.

It However, there are cases in practice where such an orderly dismantling is not feasible, z. B. in the decomposition of radioactively contaminated apparatus such. B. shell and tube heat exchangers, the previously in the primary circuit a nuclear power plant were in use. A regular disassembly such an apparatus would who dealt with it Worker one inadmissible exposure to high and long radiation dose, which is why others in such cases technical paths must be taken.

So is in the EP 0 327 841 B1 describes a method in which a radioactively contaminated component is sawn, whereby contaminated sawing material or Sägespane incurred. In order to bind them already during the sawing process and thus not even let them enter the environment, the contaminated component as a whole is frozen in an ice block, ie completely enveloped by this block of ice. Then the block of ice is sawed with the component therein, the resulting sawdust are immediately tied back in the ice of the block of ice and therefore they do not leave the block of ice.

The procedure according to EP 0 327 841 B1 is very expensive. It is necessary, with considerable expenditure of time and energy, to produce an ice block whose extent, since the component must be completely encased by the block of ice, still considerably exceeds the extent of the component. Once created, the block of ice must maintain this state of aggregation during the subsequent sawing process. It is therefore necessary to carry out the sawing in an at least strongly cooled down room, which in turn is associated with a considerable use of energy. But also the time required for the implementation of the known method is extremely large. Until the complete inclusion of the component in an ice block is expected to take a time of three to four months.

Of the Invention is based on the object, a method for disassembly one from a housing and internals disposed therein existing procedural To create apparatus that is feasible with low energy input.

• a) Einfüllen einer im Verarbeitungszustand sprüh- oder fließfähigen, verfestigbaren Masse in das Gehäuse derart, daß sich die Masse um die Einbauten herum in dem Gehäuse verteilt,
• b) Verfestigenlassen der eingefüllten Masse,
• c) Zerschneiden des Apparates in einzelne Elemente leicht zu transportierender Größe,
• d) Entfestigen der in den einzelnen Elementen enthaltenen Masse, vorzugsweise durch deren erneute Überführung in den sprüh- bzw. fließfähigen Zustand.

To solve a process for disassembling a consisting of a housing and disposed internals procedural apparatus, for. B. a shell-and-tube heat exchanger, proposed with the following steps:

• a) filling in the housing a sprayable or flowable, solidifiable mass in the housing in such a way that the mass distributed around the internals in the housing,
• b) allowing the filled mass to solidify,
• c) cutting the apparatus into individual elements of easily transportable size,
• d) softening the mass contained in the individual elements, preferably by their renewed transfer into the sprayable or flowable state.

Thus, according to the invention a spray or flowable mass in the case the procedural apparatus filled so that this mass to the in the housing arranged internals distributed around. In a subsequent step the solidification of the thus filled mass, whereby the in the housing arranged fixtures fixed in their respective position within the housing become. In the subsequent Cutting the apparatus into individual elements may result this fixing to none for the fragmentation process and especially for the service life of the cutting tool unfavorable vibration of the internals come. In a further process step, a softening then takes place the mass, preferably by their renewed transfer into the spray or flowable condition. As a result, then the fixtures or their sawed individual parts from the actual housing solve the process engineering apparatus and optionally separated for further disposal.

The method according to the invention can be carried out particularly advantageously on tube bundle heat exchangers which are composed of a heat exchanger housing and tubes arranged in a parallel or U-shaped manner for the one heat exchanger fluid. When cutting such a heat exchanger, the tubes usually perform a very strong intrinsic movement within the housing, in particular they tend under the influence of the cutting forces to vibrate. This vibration is prevented by the inventive fixation of the individual tubes within the housing, so that there is a cut through the procedural apparatus clean and while preserving the cutting tool perform.

Preferably the cutting of the apparatus takes place transversely to the longitudinal extent in the case arranged fittings. In case of using the method for Disassembling a shell and tube heat exchanger Therefore, the cutting planes are at right angles to the longitudinal extent to lay the individual tubes.

With a further embodiment of the method according to the invention is proposed that this Slicing in a opposite the environment hermetically sealed room is remotely controlled. This variant is used when the relevant procedural Apparatus is radioactively contaminated. By arranging the one to be cut Apparatus in a hermetically sealed room, the danger is excluded that employee too close and too long in the immediate vicinity of the contaminated Stop the apparatus. The cutting takes place remotely controlled and monitored from one through a glass pane opposite the actual work space disconnected control room. The cutting is also done at normal temperature, which is why it does not require the room as a cooling chamber including to provide the provision of appropriate cooling units.

With another embodiment of the method is proposed that the solidifiable mass at normal temperature to a solid foam curing liquid is. Particularly suitable as a solidifying mass is a polyurethane foam, as in the fields of construction technology and building equipment as Mounting foam is known. Polyurethane foam can be restored by heating convert into a flowable state of matter, wherein the accumulating liquid, as far as the process that saw up a radioactively contaminated component, disposed of got to. The this amount of liquid However, it is low because z. B. in the use of polyurethane the Volume of cured foam which is 30 to 100 times the volume of the liquid.

With In a further embodiment, it is finally proposed that the cutting with a band saw takes place, the saw band with a liquid chilled becomes. The biggest part this liquid can in the pipes of the process engineering apparatus, their cross sections while the foaming process remain free, run down, and is caught there. One further part of the cooling liquid for the bandsaw let yourself in the area of the outer jacket of the apparatus housing collect and, if necessary, also dispose of it.

in the The following is the invention with reference to an embodiment only showing drawing in more detail explained. Show:

1 in a sectional view of a closed space with a sawing device arranged therein and a mounted on the sawing device, to be dismantled process engineering apparatus and

2 a section through the process engineering apparatus in the in 1 registered level II.

1 shows a hermetically sealed to the environment space 1 with a cutting device arranged therein 2 , which is designed here as a band saw. The cutting device 2 consists of a vertical mast 3 , at the bottom of a prop 4 as well as at different heights arms 5 are attached. On the support 4 relies on a process engineering apparatus 6 starting with the cutting device 2 to be cut. For additional stabilization of the apparatus 6 During the cutting process are also attached to different heights arms 5 with the apparatus 6 connected, z. B. via suitable welds.

The support 4 performs a double function. On the one hand, it serves to hold and stabilize the material to be cut, ie the process engineering apparatus 6 during the cuts to be made. On the other hand, the prop forms 4 a guide on which the actual cutting apparatus 8th can move up and down to perform cuts at different heights. The cutting apparatus 8th is about a vertical axis 9 rotatably mounted, so that a cutting arm 10 of the cutting apparatus 8th Can perform cutting movements within a horizontal plane. The endless saw band is denoted by the reference numeral 11 Mistake.

At the in 1 presented procedural apparatus 6 it is a shell-and-tube heat exchanger, which comes from the primary circuit of a nuclear power plant. The apparatus 6 consists of a cylindrical housing 12 which is in its lower part with two collectors 13a . 13b is provided. Above the two collectors 13a . 13b there is a tube plate 14 , From the tubesheet 14 out lead pipes 15 through the interior of the housing. The pipes 15 are in the upper part of the apparatus 6 bent over by 180 °, so that an overall U-shaped course of the tubes 15 results, with the main longitudinal extent of the pipes paral Lel extends to the longitudinal extent of the substantially cylindrical housing 12 ,

The levels in which the cutting apparatus 8th the cutting device 2 horizontal cuts are performed in 1 with the reference number 16 designated. It can be seen here that the process engineering apparatus 6 is cut or sawed into easily transportable round discs.

2 shows a section through the process engineering apparatus 6 in the in 1 Plotted sectional plane II. Visible are the cylindrical housing 12 as well as arranged in alignment with the housing tubes 15 , The cutting planes 16 extend at right angles to the longitudinal extension of the housing and pipes of the process engineering apparatus.

To carry out the process, a sprayable or flowable mass is introduced into the apparatus 6 filled that mass around the pipes 15 around inside the whole case 12 distributed. In the interior of the pipes 15 no mass is filled into it. The mass is preferably made of a foam-forming material, for. As a polyurethane foam. After foaming, the mass fills the entire volume of the apparatus 6 except for the interior of the pipes 15 out. The curing of the polyurethane foam causes the tubes to become inside the housing 12 fixed in their respective position.

Basically it has to be at the filled Do not mass around a liquid act. Also a flowable bulk material like z. B. a subsequently curing Granules are suitable as mass.

This fixation is of considerable advantage for the subsequent process step of sawing along the individual cutting planes 16 , Because the pipes 15 are fixed by the foam and thus stabilized, they can perform during the sawing no significant movements, and in particular do not vibrate.

The cutting is done in such a way that step by step starting from the top, the individual cutting planes 16 be performed. The required stability of the apparatus 6 during the cutting process is through the mast 3 ensured with the apparatus 6 over the arms 5 connected is. Sections of the prop 4 that are no longer needed are through the saw band 11 immediately with severed.

After this the last cut was done is the process engineering apparatus in individual elements of each easily transportable size before, preferably a Weight not exceeding 10 tons. Within this individual elements are the pipe sections running there as before stabilized by the polyurethane foam.

All of the aforementioned method steps are within the hermetically sealed space 1 performed at normal room temperature. The operation of the cutting device 2 This is done remotely under observation of a control station, which is outside the room 1 located.

The elements formed by cutting can then in z. B. transported a repository. There is a softening of the contained in the individual elements, hardened mass, preferably by re-transfer of this mass in the sprayable or flowable state. In the case of a polyurethane foam z. B. can be dissolve by strong heating of the elements of this foam, wherein liquid accumulates, the volume of which is significantly less than the volume of the polyurethane foam. This liquid is disposed of properly. The coolant used during sawing is also disposed of. Most of this coolant passes over the inside of the open tubes 15 already during the sawing process into one of the two collectors 13a . 13b , and can be removed from there further. The remaining cooling liquid is on the outer surface of the housing 12 intercepted in a suitable manner, for. B. by an outside attached to the housing gutter.

Of the Energy input for operating the described method is very low. Ultimately, this reduces to the drive power for the saw as well the energy for introducing the later hardening mass into the interior the procedural apparatus, if necessary also still to reliquefy the mass required energy.

1

room

2

cutter

3

mast

4

support

5

connecting arm

6

process engineering apparatus

8th

cutting machine

9

axis

10

cutting arm

11

bandsaw

12

casing

13a

collector

13b

collector

14

tube sheet

15

pipe

16

cutting plane

Claims (7)

Method for disassembling a housing ( 12 ) and internals arranged therein ( 15 ) existing process engineering apparatus ( 6 ), z. B. a shell and tube heat exchanger, comprising the following steps: a) filling a sprayable or flowable in the processing state, solidifiable mass in the housing ( 12 ) such that the mass around the internals ( 15 ) around in the housing ( 12 b) solidifying the filled mass, c) cutting the apparatus ( 6 ) in individual elements of easily transportable size, d) softening the mass contained in the individual elements, preferably by their renewed transfer into the sprayable or flowable state. A method according to claim 1, characterized in that the cutting of the apparatus transversely to the longitudinal extent of the in the housing ( 12 ) arranged internals ( 15 ) he follows. Method according to one of the preceding claims, characterized in that the cutting in a hermetically sealed space ( 1 ) is remotely controlled. Method according to one of claims 1 to 3, characterized that the solidifiable mass at normal temperature to a solid foam curing liquid is. Method according to claim 4, characterized by a Polyurethane foam as a solidifiable mass. Method according to claim 5, characterized in that that this Softening the mass by heating the individual elements takes place. Method according to one of the preceding claims, characterized in that the cutting takes place with a band saw, wherein the saw band ( 11 ) is cooled with a liquid.