WO2020192966A1 - Method and module set for producing a steam cracking system - Google Patents

Abstract

The invention relates to a method for producing a steam cracking system (100). The steam cracking system (100) has a cracking furnace (10) with a convection zone (11) and a radiation zone (12), and cracking tubes (122) are led through the radiation zone (12) and are connected to one or more quenching heat exchangers (15) via one or more transfer lines (14). At least one part of the radiation zone (12) is prefabricated in the form of one or more furnace modules (II— V) together with the cracking tubes (122) at a pre-assembly location, wherein the furnace module(s) (II— V) is/are transported to a production location and is/are used at the production location in order to produce the steam cracking system (100). The invention likewise relates to a corresponding module set.

Description

description

Process and module set for the creation of a steam cracking system

The present invention relates to a method and a set of modules for creating a steam cracking system according to the generic terms of the independent

Claims.

State of the art

Processes and systems for steam cracking have been known for a long time and are extensively described in the specialist literature. In this context, the article "Ethylene" in Ullmann's Encyclopedia of Industrial Chemistry, online edition, 2007, DOI 10.2002 / 14356007 should be referred in particular. a10_045.pub2, referenced.

Steam cracking systems (often also referred to as ethylene systems) with so-called cracking furnaces are used for steam cracking. These cracking furnaces can also be provided in several groups and operated under different conditions or supplied with different inserts (English feeds). Cracking furnaces typically have a so-called convection zone (English convection section) and a so-called radiation zone (English radiant section). The radiation zone is fired by means of burners arranged at least on the bottom. Flue gases from the radiation zone flow off via the convection zone.

The convection zone is typically used to preheat boiler feed water, to generate or further heat steam and / or to preheat the reaction insert or to further heat a mixture from

Reaction insert and steam. For this purpose, appropriate tube bundles are passed through the convection zone. The mixture of reaction feed and steam is passed through the radiation zone in so-called cans (coils) for conversion. The cans can be provided in various configurations and arrangements described in the specialist literature.

The so-called cracked gas, which is discharged from the radiation zone via the cracked tubes mentioned and initially at a temperature of typically 750 to 875 ° C is present, must in order to bring the reactions as quickly as possible to a standstill and thus an excessive formation of undesirable

To prevent by-products to be cooled as quickly as possible. So-called quench heat exchangers, which can be subdivided in particular into so-called primary and secondary quench heat exchangers (English. Primary Quench Exchanger, Secondary Quench Exchanger), serve to cool the fission gas. Different designs are also described in the specialist literature.

Depending on its composition, which depends in particular on the reaction inserts and cracking conditions used, the correspondingly cooled cracked gas is subjected to water and / or oil scrubbing, then compression and acid gas removal as well as fractionation operated at least partially at cryogenic temperatures in order to obtain the desired products,

traditionally ethylene to be obtained from the cracked gas.

With the previous design and assembly concept of steam cracking systems, the cracking furnaces are delivered to the construction site in many individual parts and assembled accordingly on site. Occasionally, tube bundles for the convection zone are prefabricated and delivered in modular design. Nevertheless, intensive assembly work is required on the respective construction site.

The present invention has the task of creating

To facilitate steam cracking systems, especially the cracking furnaces mentioned. Disclosure of the invention

This object is achieved by a method and a set of modules with the respective features of the independent patent claims. Refinements are the subject matter of the dependent claims and the description below.

The method proposed according to the invention overcomes the problems associated with the previous concept of intensive "on-site" assembly. Such problems are posed in particular by the requirements or

Regulations regarding compliance with occupational health and safety and environmental requirements, but also, for example, hindering environmental influences, which even at times

Setting the assembly activities can lead.

Overall, the known methods involve a great deal of effort in order to permit and administer a construction site for a steam cracking system, with corresponding disruptions and restrictions in the rest of the system operation. The disruptions associated with the creation of a steam cracking system and

Restrictions are correspondingly longer-term due to the complex and therefore long installation time. In certain regions, there are extremely high assembly costs due to increasing demands on the plant construction sites and the inefficiency of the assembly work.

The new construction concept proposed according to the invention at least partially overcomes these disadvantages and minimizes the installation time and thus also the costs and risks for customers for the construction of steam cracking systems.

In the new design and assembly concept proposed according to the invention for steam cracking systems or the corresponding cracking furnaces, according to our knowledge, it is possible for the first time to use the radiation zone areas of cracking furnaces in addition to the convection zone modules with appropriate furnace modules and prefabricated ones

To deliver assembly frames (skids) and large components to the construction site and to install them there with minimal assembly effort and reduced assembly time.

In the context of the present invention, a cracking furnace is designed in such a way that it is divided into several furnace modules, which are then connected to one

Prefabrication Yard can be built and then delivered to the construction site using suitable means of transport and assembled to the finished furnace in a significantly reduced time. In the method proposed according to the invention, in particular

characterizing that the corresponding furnace modules are already fully equipped with the radiation zone tube system, arranged outside the radiation zone

Pipework, one or more quench heat exchangers (in particular one or more primary quench heat exchangers, but also optionally one or more secondary quench heat exchangers) and one or more lines between the radiation zone and the one or more

Quench heat exchangers (and possibly between primary and secondary

Quench heat exchangers, if these are also part of the furnace module) including the respective welds.

Particular advantages of the method proposed according to the invention also result from the fact that corresponding pressure-bearing parts can be preassembled and the corresponding pressure tests can be carried out in advance.

In addition, in particularly advantageous refinements of the invention, external insulation, expanded internal floor insulation (refractory lining) or other fireproof insulation, instrumentation and electrical components and, if applicable, their cable connections can be preassembled.

Against this background, the present invention proposes a method for creating a steam cracking system, the steam cracking system, as is basically known and explained above, a cracking furnace with a convection zone and a

Has radiation zone. In the steam cracking system created according to the invention, cans are passed through the radiation zone and over one or more

Transfer lines connected to one or more quench heat exchangers.

As already explained, in the conventional method a corresponding creation of a steam cracking system and thus also the connection of the

Transfer lines with the quench heat exchanger or the cans on the construction site. In contrast, the present invention proposes that at least a part of the radiation zone in the form of one or more furnace modules with the

Canned tubes is prefabricated at a pre-assembly location, the furnace module or modules being transported to the respective production site after prefabrication and being used at the production site to create the steam cracking system. The advantages of the measures proposed according to the invention have already been partially explained above. The present invention in particular enables extensive standardization of both the furnace design and the

Creation process of a corresponding steam cracking system. In the meaning of

The system design or the furnace modules are already available as

Considered sub-assemblies and tested accordingly non-destructively, which is too clear reduced effort on the construction site with regard to the entire acceptance of the system and results in significant time savings. In the context of the present invention, there is also an advantage with regard to the creation of the

Steam cracking system and the storage space required in this context. When using the appropriate furnace modules, the customer has to provide fewer so-called utilities such as electricity and water.

Overall, by using the proposed according to the invention

Measures the furnace construction time on site can be significantly reduced. In the context of the present invention, assembly times can be reduced significantly, depending on the type of furnace by approx. 30 to 50%. Steam cracking systems planned and constructed within the scope of a method according to the invention also have clear advantages when converting existing systems (revamps). The construction site situation at the place of use, i.e. at the construction site of the steam cracking system, is significantly improved and shortened, among other things with regard to safety and environmental requirements, the installation time and the entire schedule due to lower scaffolding costs, crane times, overheads and the like, the product and installation quality, the dependency of environmental and weather influences, the deployment of administration and monitoring staff by the plant operator and the disruptive effects on ongoing plant operation. The present invention leads overall to a significantly more economical plant construction with corresponding technical advantages with regard to safety and maintainability.

As already explained, the furnace module or modules prefabricated within the scope of the present invention can also be prefabricated with the quench heat exchanger or heat exchangers. This results in a further degree of prefabrication and lower assembly costs for the entire pressure-side components or these components up to a corresponding quench heat exchanger. When

Quench heat exchangers can be included in the prefabrication according to the invention not only a primary but also a primary and a secondary quench heat exchanger. In turn, more extensive prefabrication results in less effort when creating the system at the place of installation.

For the sake of clarification, it should be noted that the

Quench heat exchangers to typical transfer line heat exchangers for Can act steam cracking systems in which several pipelines are led through a cold room through which water or steam flows.

As also mentioned, the oven module or modules on the

Prefabrication site are subjected to one or more functional tests, wherein the functional test or tests can in particular include a pressure test. The furnace module or modules can also be provided with an external insulation, a

Interior floor insulation, instrumentation and / or electrical components and / or their connections are prefabricated. In the case of a higher degree of prefabrication in the manner explained, further functional testing can also be carried out on

Pre-fabrication site, so that this can be largely or at least partially dispensed with at the place of manufacture.

As already mentioned, several additional modules can be prefabricated at the prefabrication site or at a further prefabrication site and at the creation site

Creation of the steam cracking system can be used, in particular one or more furnace floor modules, one or more access modules in the form of stairwells and the like, one or more piping support modules, one or more feed line modules, one or more high pressure line modules, in particular for high pressure steam, and / or one or more drainage modules. A corresponding steam cracking system also typically includes a smoke gas discharge system with, if necessary, corresponding smoke gas cleaning. Such modules can also be used if necessary

are prefabricated according to the invention. In particular, within the scope of the present invention, the

Oven modules are prefabricated on the basis of a dimension and / or weight specification, in particular with regard to the portability of corresponding modules. The design of the furnace modules can be adapted to include existing pipe bridge heights to be taken into account or others

Road transport restrictions such as bridges, loads, driveways and the like.

By using the assembly concept proposed according to the invention, a novel logistical concept for cracking furnaces or

Steam cracking systems are realized, namely the possibility of transport while using the advantages of the modularized construction concept. this leads to Significantly lower deliveries to the construction site with the advantages of correspondingly lower associated costs on the construction site. This represents one

A decisive advantage over other variants, for example, in which a complete furnace is pre-assembled and moved to the final installation site. A modularized creation of a steam cracking system according to an embodiment of the invention has the advantage of being easy to transport with common

Means of transport and via common transport routes.

The proposed module set according to the invention for creating a

Steam cracking system benefits in the same way from the advantages explained above, so that reference can be made to the explanations above in this regard.

The invention is explained in more detail below with reference to the accompanying drawings, which illustrate preferred embodiments of the invention.

Brief description of the drawings

FIG. 1 illustrates a steam cracking system that can be created according to an embodiment of the invention in a greatly simplified, schematic partial representation.

FIGS. 2A and 2B each illustrate a steam cracking system that can be created according to an embodiment of the invention, with and without corresponding modules, in a simplified, schematic partial representation in a front view. FIGS. 3A and 3B each illustrate a steam cracking system that can be created according to an embodiment of the invention, with and without corresponding modules, in a simplified, schematic partial representation in side view.

Detailed description of the drawings

In the figures, structurally or functionally corresponding elements are indicated with identical reference symbols and are not explained repeatedly for the sake of clarity. In Figure 1, one can be created according to an embodiment of the invention

Vapor cracking system illustrated in a greatly simplified, schematic partial representation and denoted as a whole by 100. The steam cracking system 100 illustrated in FIG. 1 comprises one or more cracking furnaces 10, shown here with a reinforced line. Typical steam cracking plants 100 comprise a number of corresponding cracking furnaces 10 which can be operated under the same or different conditions. Furthermore, corresponding cracking furnaces 10 can have the components explained below in one or a plurality.

The cracking furnace 10 comprises a convection zone indicated here as a whole as 11 and a radiation zone indicated here as a whole as 12. In refinements, provision can also be made, for example, to assign several radiation zones 12 to a convection zone 11.

In the example shown, several heat exchangers 1 1 1 to 1 15 are arranged in the convection zone 1 1, each of which is also in a different arrangement or arrangement.

Sequence in the convection zone 1 1 can be provided. This

Heat exchangers 1 1 1 to 1 15 are typically in the form of through the

Convection stone 11 guided tube bundles are formed and flue gas from the radiation zone 12 flows around them. In the example shown, the radiation zone 12 is heated by means of a plurality of burners 121, which are only partially designated separately here, on the bottom and on the wall. Heating on the floor only is also possible.

In the example shown, a gaseous or liquid feed stream 101 containing hydrocarbons is fed to the steam cracking system 100. Also the

Use of several feed streams 101 is possible. The feed stream 101 is initially preheated in the heat exchanger 11.

Furthermore, a boiler feed water flow 102 is passed through the convection zone 1 1 or the heat exchanger 1 12 and is preheated. The boiler feed water flow 102 is then fed into a steam drum 13. In the heat exchanger 1 13 in the convection zone 1 1, a process steam flow 103, which can also be provided using the steam drum 13, is further heated and with the

Feed stream 101 combined.

A collection stream 104 formed in this way from the feed and steam is passed through a further heat exchanger 115 in the convection zone 11 and then passed through the radiation zone 12 in typically several cans 122. The representation in Figure 1 is greatly simplified. Typically a

corresponding collecting flow 104 is divided into a multiplicity of can 122 and, after passing through the radiation zone 12, is combined again as a cracked gas flow in a common line (not illustrated).

As further illustrated in FIG. 1, a steam stream 105 can be removed from the steam drum 13 and heated in a further heat exchanger 114 in the convection zone 11, whereby a high-pressure steam stream 106 can be generated. This can be used at a suitable point in the steam cracking system 100.

Fission gas discharged from the radiation zone 12 or the can 122 is fed via one or more transfer lines 14 to a quench heat exchanger 15 and is cooled there. In the example shown, the quench heat exchanger 15 represents a primary quench heat exchanger. In addition to a primary quench heat exchanger 15, secondary quench heat exchangers can also be present. Cooled cracked gas is fed via a line 16 to further process units, which are indicated here only very schematically with 17. With these others

Process units 17 can in particular be process units for washing, compressing and fractionating the cracked gas. In the example shown, the quench heat exchanger 15 is charged with a water stream 106 from the steam drum 13. A steam stream 107 formed in this way in the quench heat exchanger 15 is returned to the steam drum 13.

An essential aspect of a method used in accordance with an embodiment of the present invention for creating a corresponding steam cracking system 100 is to at least part of the radiation zone 12 with at least the

Provide cans 122 in the form of one or more furnace modules. Other components can also be included accordingly. A corresponding furnace module, which is shown in dash-dotted lines in FIG. 1 and denoted overall by II, can also include one or more quench heat exchangers 15. The furnace module or modules II are used within the scope of the present invention or a corresponding configuration that is used to create the

Steam cracking system 100 according to FIG. 1 is used, prefabricated at a pre-assembly location, transported to a corresponding creation location, and on

Creation site used to create the steam cracking system 100. An essential aspect of the present invention is to equip a corresponding unit with the cans and to subject them to a pressure test at the pre-assembly location, for example.

As illustrated in the following figures, a corresponding

Steam cracking system 100 also have further oven modules III-V in addition to oven module II, as well as further modularized units that are prefabricated as a module set at the pre-assembly site or at different pre-assembly sites

can then be transported to the place of creation.

In FIGS. 2A and 2B, a vapor cracking system that can also be created in accordance with an embodiment of the present invention is illustrated in a more detailed representation than in FIG. FIG. 2A shows the steam cracking system 100 without the corresponding modules and FIG. 2B shows the steam cracking system 100 with these. The modules are represented by rectangles that cover the components they contain.

A furnace module, which has already been illustrated in FIG. 1 and shown there in a highly simplified manner and designated by II, is also provided here. Furthermore, the

Steam cracking system according to FIGS. 2A and 2B further furnace modules designated here with III-V. The furnace modules II-V form the entire radiation zone of a cracking furnace of the steam cracking system 100 of FIGS. 2A and 2B. A further module that is used in the creation of the steam cracking system 100 according to FIGS. 2A and 2B is a furnace floor module I, which can in particular include floor interior insulation or burners or preparatory components for attaching burners.

Furthermore, in Figures 2A and 2B, an access module VI with a lower part of a stairwell, another access module VII with an upper part of a

Stairwell, a lower piping support module VIII, an upper

Piping support module IX, a feed line module X, a high pressure line module Xa and a discharge module XI illustrated. Figures 2A and 2B also show further modules XX, XXI and XXII, which are used in the discharge of flue gases or

Product streams can be used.

In FIGS. 3A and 3B, the steam cracking system already illustrated in FIGS. 2A and 2B is shown again in a side view. The explanations for FIGS. 2A and 2B apply in a corresponding manner, further modules being illustrated here, but not being explained separately. The modules already explained above are also partially illustrated, but partially covered due to the different representation.

Claims

Claims 1. A method for creating a steam cracking system (100), wherein the Steam cracking system (100) has a cracking furnace (10) with a convection zone (1 1) and a radiation zone (12) and with cracking tubes (122) guided through the radiation zone (12) and via one or more transfer lines (14) with one or more Quench heat exchangers (15) are connected, characterized in that at least part of the radiation zone (12) in the form of one or more furnace modules (II-V) with the cans (122) is prefabricated at a pre-assembly location, the furnace module or modules (II- V) transported to a creation location and at the creation location for the creation of the Steam cracking system (100) is or are used. 2. The method according to claim 1, in which the furnace module or modules (II-V) is or are further prefabricated with the quench heat exchanger or heat exchangers (15). 3. The method according to claim 2, wherein the furnace module or modules (II-V) is or are prefabricated with several quench heat exchangers (15), the several quench heat exchangers (15) comprising one or more primary quench heat exchangers and one or more secondary quench heat exchangers. 4. The method according to any one of the preceding claims, in which the or at least one of the plurality of quench heat exchangers (15) is designed as a heat exchanger in which a plurality of pipes (141) are guided through a cooling chamber through which water or steam flows. 5. The method according to any one of the preceding claims, wherein the or the Oven modules (II-V) is or will be subjected to one or more functional tests at the prefabrication site. 6. The method of claim 5, wherein the one or more functional tests comprise at least one pressure test. 7. The method according to any one of the preceding claims, wherein the or the Oven modules furthermore with an external insulation, an internal floor insulation Instrumentation and / or electrical components and / or their connections is or will be prefabricated. 8. The method according to any one of the preceding claims, in which one or more further modules (VI-XI) at the prefabrication site or at another Prefabrication site to be prefabricated. 9. The method according to claim 8, in which the further module or modules (VI-Xl) one or more furnace base modules (I), access modules (VI, VII), Piping support modules (VIII, IX), feed line modules (X), High pressure line modules (Xa) and / or drainage modules (XI) comprise. 10. The method according to any one of the preceding claims, in the or the Oven modules (II - V) are prefabricated on the basis of a dimension and / or weight specification. 1 1st module set for creating a steam cracking system (100), whereby the Steam cracking system (100) has a cracking furnace (10) with a convection zone (11) and a radiation zone (12) and with cracking tubes (122) guided through the radiation zone (12) and via one or more transfer lines (14) with one or more quench heat exchangers (15) are connected, characterized in that the module set is one or more Furnace modules (II-V) with the cans (122), wherein the one or the Furnace modules (II-V) can be transported to the place of creation and can be used at the place of creation to create the steam cracking system (100). 12. Module set according to claim 1 1, which further includes one or more further modules (Vl-Xl), comprising one or more furnace bottom modules (I), access modules (VI, VII), piping support modules (VIII, IX), feed line modules (X), Has high-pressure line modules (Xa) and / or discharge modules (XI).