Quench system

Abstract

The present invention relates to a quencher system for a plant for the treatment of cracking furnaces with liquid and gaseous feedstocks, comprising a primary heat exchanger or PQE (10) and a secondary heat exchanger or SQE (11) and a tertiary heat exchanger or TQE (12) connected in series, wherein a transfer line heat exchanger for double operation or TLX-D (26) is arranged and configured as a tertiary heat exchanger, the TLX-D (26) is connected in series to the secondary heat exchanger or SQE (11) through a TLX-D gas feed pipe (24), the TLX-D (26) is connected to a steam drum (59) connected to a feedwater supply pipe (49) through a TLX-D feedwater guide pipe (34) and a TLX-D riser pipe (46) and a TLX-D downcomer pipe (38), the SQE (11) is connected to the steam drum (59) connected to the feedwater supply pipe (49) through a SQE downcomer pipe (52) and a SQE riser pipe (57).

Description

Technical Field

[0001] This invention relates to a quench system and a process for a quench system for a pyrolysis furnace using liquid and gaseous feedstocks, the system comprising a primary heat exchanger, a secondary heat exchanger, and a tertiary heat exchanger connected in series. Background Technology

[0002] Several feedstocks require further processing in a cracking furnace for use in an ethylene furnace, also known as a cracking furnace. These feedstocks include naphtha, also called liquid feedstock (liquid feed), and gas, also called gaseous feedstock with a high ethylene content (gas feed). Both feedstocks are heated to high temperatures in the cracking furnace and then immediately cooled using a quench system, also known as QS.

[0003] Quenching systems, or QS, require special construction depending on the feedstock, as the physical properties of the feedstock differ. Gas feedstocks can be cooled downwards to a greater extent than liquid feedstocks; for example, a gas can be cooled from 900°C to 150°C, while a liquid feedstock can be cooled from approximately 900°C to 350°C, because condensation of the gas only begins at significantly lower temperatures.

[0004] Therefore, quench systems used in gas feed mode typically include a primary heat exchanger (PQE), a secondary heat exchanger (SQE), and a tertiary heat exchanger (TQE).

[0005] Quenching systems for liquid feed mode consist only of PQE and SQE connected in series. TQE, which is typically used as a feedwater preheater or boiler feedwater preheater, is not installed in such an arrangement where PQE and SQE are each connected and operate as evaporators.

[0006] The following figures further illustrate examples of possible cooler arrangements in the operating mode of a quench cooler system for a gas-feed mode.

[0007] The following figures further illustrate examples of possible cooler arrangements in the operating mode of a quencher system for a liquid feed mode.

[0008] DE 10 2014 018 261 A1 is mentioned as prior art.

[0009] The following figures further illustrate an example of the processing procedure of another type of pyrolysis furnace already in use, which is a quench system with gas feed mode and liquid feed mode operation.

[0010] To operate a quencher system using both liquid and gaseous feedstocks, a PQE, SQE, and TQE must be installed. In liquid feed operation mode, the TQE on the gas side should be bypassed.

[0011] The current operating mode of a prior art quencher system for gas and liquid feed, as explained in the accompanying drawings, is performed via this bypass circuit. In gas feed operation, the intake valve located upstream of the TQE intake pipe is open, and the bypass valve located in the TQE bypass is closed. In liquid feed operation, the intake valve is closed, and the bypass valve is open.

[0012] The disadvantages of the existing quencher system layout for gas-feed and liquid-feed operation modes are that this layout with bypass control requires a very large space and thus results in high costs. In addition, this technical layout and operation mode cannot fully meet the requirements for reliability, ease of maintenance and upkeep of such quencher systems. Summary of the Invention

[0013] The purpose of this invention is to provide a quench system and a process for a quench system for a pyrolysis furnace using liquid and gaseous feedstocks, which improves reliability and cost by reducing the high requirements for technical equipment and operating modes, and ensures simplicity in terms of necessary repair and maintenance.

[0014] The object of this invention is achieved by arranging and configuring a conveyor line heat exchanger (hereinafter referred to as TLX-D) for dual or alternating operation in a general manner as a three-stage heat exchanger. The TLX-D is connected in series to a secondary heat exchanger or SQE via a TLX-D gas feed pipe. The TLX-D is connected to a steam drum connected to a feed water supply pipe via a TLX-D feed water guide pipe, a TLX-D riser pipe, and a TLX-D downcomer pipe. Meanwhile, the SQE is connected to a steam drum connected to a feed water supply pipe via an SQE downcomer pipe and an SQE riser pipe.

[0015] In addition, the TLX-D is equipped with a TLX-D water supply pipe, which is fitted with TLX-D water supply pipe valves. Furthermore, TLX-D water supply guide pipe valves are installed on the TLX-D riser pipe, and TLX-D downcomer pipe valves are installed on the TLX-D downcomer pipe. Preferably, the TLX-D achieves natural water circulation cooling through the TLX-D downcomer pipe and TLX-D riser pipe.

[0016] One important advantage is that the TLX-D is connected to the provided TLX-D feedwater supply pipe equipped with TLX-D feedwater supply pipe valves, and is also connected to the steam drum via the TLX-D feedwater guide pipe equipped with TLX-D feedwater guide pipe valves, wherein forced circulation cooling in the TLX-D is carried out through the arranged TLX-D feedwater supply pipes and TLX-D feedwater guide pipes.

[0017] Advantageously, the TLX-D is arranged and configured for dual operation, such that the TLX-D has several baffles arranged at a certain distance from each other, wherein the baffles, which are surrounded by the TLX-D housing, are arranged inside the TLX-D and perpendicular to the centerline of the horizontally positioned TLX-D, while the arrangement and position of the baffles are predetermined based on the additional steam generated in the liquid feed mode.

[0018] Advantageously, a first baffle is installed inside the TLX-D and at a predetermined distance from the TLX-D feedwater inlet pipe. This first baffle deflects the supply water flow on the shell side by 180° and has a free supply water flow cross-section. Its maximum height, as a function of predetermined process conditions, is in the range of 10% to 40% of the TLX-D shell inner diameter, preferably in the range of 15% to 25%. Furthermore, a second baffle is arranged inside the TLX-D and at a predetermined distance from the first baffle. This second baffle also deflects the supply water by 180° and has a free supply water flow cross-section. Additional baffle assemblies are provided as a function of the length of the TLX-D up to the TLX-D feedwater outlet pipe.

[0019] Another feature is that the corresponding length of the TLX-D with predetermined process conditions is predetermined on both the gas side and the water / steam side, and the number of baffles arranged is adjustable as a function of the predetermined process conditions, with the distance between each baffle ranging from about 100 mm to 800 mm, preferably from 300 mm to 600 mm.

[0020] Another advantage is that the baffle in the TLX-D, which is perpendicular to the centerline of the TLX-D, has a flat structure in the upper region when the water supply flows through the horizontal position of the TLX-D, and a free volume or steam space is arranged below the riser branch of the TLX-D.

[0021] Another advantage is that, in the TLX-D, the flat end of the baffle is kept small on the one hand so that no unwanted bypass flow occurs during the operation of the TLX-D as a feedwater preheater in gas feed mode, and on the other hand, the flat end of the baffle is configured to be large so that the amount of steam generated can be completely discharged during the operation of the TLX-D as an evaporator in liquid feed mode. The maximum height of the flat end is preferably configured in the range of about 5 mm to 40 mm, preferably in the range of 10 mm to 15 mm.

[0022] In the processing of quencher systems for cracking furnaces using both liquid and gaseous feedstocks, it has proven particularly advantageous that the TLX-D dual heat exchanger or the TLX-D as a tertiary heat exchanger is connected for dual operation. Simultaneously, in the case of gaseous feedstock, the TLX-D operates as a feedwater preheater in gas feed mode, and in the case of liquid feedstock, the TLX-D operates as an evaporator in liquid feed mode. In gas feed mode, the TLX-D feedwater supply valve and feedwater valve are open, while the TLX-D downcomer valve and TLX-D riser valve are closed.

[0023] In the process, another advantage is that, under the countercurrent principle, the water supplied on the shell side is guided in the opposite direction to the flow of the gaseous cracked gas, and is cooled to a predetermined temperature in the TLX-D through the open TLX-D water supply pipe valve.

[0024] Another advantage is that the heat from the pyrolysis gas discharge in the TLX-D will heat the feed water from about 150°C to about 300°C.

[0025] In the TLX-D, it is advantageous to open the TLX-D downcomer valve and the TLX-D riser valve in liquid feed mode, and close the TLX-D feedwater supply valve and the feedwater valve, and guide the feedwater to the steam drum through the installed feedwater supply pipe.

[0026] Another advantage is that the TLX-D dual heat exchanger is integrated into the saturated steam system or cooling system of the quench system, in which water is drawn from the steam drum through the TLX-D downcomer and the open TLX-D downcomer valve until it is distributed to the TLX-D downcomer branch installed on the TLX-D.

[0027] Furthermore, it is advantageous that water from the steam drum flows through the TLX-D on the shell side to the TLX-D rising branch, which is arranged opposite to the TLX-D falling branch, in which the cracked gas passing through the TLX-D is not significantly cooled.

[0028] Particularly advantageously, due to the special guidance of the water flow, the inlet temperature of the cracked gas in the TLX-D is close to the saturated steam temperature, and a small amount of steam is generated on the water side or the shell side of the TLX-D shell. At the same time, the steam enters the steam drum through the TLX-D riser branch, through the TLX-D riser pipe, through the open TLX-D riser pipe valve and the TLX-D steam drum riser pipe.

[0029] The TLX-D is advantageously arranged and configured for dual operation, allowing it to be used in both gas and liquid feed modes, and in this dual operation, the TLX-D is provided as both a feed water preheater and an evaporator.

[0030] An advantageous arrangement for the TLX-D is that the operating mode is controlled via a water / steam cycle, and no longer via the gas side supplied from the PQE and SQE. Attached Figure Description

[0031] Further details and advantages of the present invention will be described in detail with reference to the exemplary embodiments shown in the accompanying drawings. In the drawings:

[0032] Figure 1 A schematic arrangement of a cooler system is shown in the operating mode of a gas-feed quench cooler system according to the prior art;

[0033] Figure 2 A schematic arrangement of a cooler system is shown in the operating mode of a liquid-feed quench cooler system according to the prior art;

[0034] Figure 3 A schematic arrangement of a cooler system is shown in the operating mode of a quench cooler system with gas feed and liquid feed and a bypass, according to the prior art.

[0035] Figure 4 A preferred exemplary embodiment of the cooler system arrangement in the operating mode of the quencher system employing gas feed and liquid feed according to the present invention is shown; and

[0036] Figure 5 A preferred exemplary embodiment of the TQE construction in the operating mode of the quencher system employing gas feed and liquid feed according to the present invention is shown. Detailed Implementation

[0037] Figure 1 A schematic arrangement of the quench system in the operating mode of a gas-feed quench system in the prior art is shown. PQE 10, SQE 11, and TQE 12 are connected in series. PQE 10 and SQE 11 are connected as evaporators, while TQE 12 operates as a water preheater. Cracking gas is supplied from a cracking furnace (not shown) to PQE 10, SQE 11, and TQE 12 in the direction of indicator arrow 13.

[0038] Figure 2 This diagram illustrates a schematic arrangement of a quench system in the operating mode of a liquid-feed quench system in the prior art. The schematic PQE 10 and SQE 11 are connected in series and operate as evaporators. The TQE, which typically operates as a water preheater or boiler feedwater preheater (abbreviated as BFW preheater), is not installed. Cracking gas from a cracking furnace (not shown) is supplied to PQE 10 and SQE 11 in the direction of indicator arrow 13.

[0039] Figure 3 This diagram illustrates a schematic arrangement of a quench system operating under both gas-feed and liquid-feed conditions, as used in prior art quench systems. PQE 10, SQE 11, and TQE 12 are connected in series. PQE 10 and SQE 11 operate as evaporators, while TQE 12 operates as a water preheater. A bypass pipe 16 is connected parallel to the horizontally arranged TQE 12 (as indicated by the arrow) between the TQE gas inlet pipe 14 and the TQE gas outlet pipe 15. The bypass pipe 16 branches off before the TQE feed valve 17, which is located on the TQE gas inlet pipe 14 of TQE 12. A TQE bypass valve 18 is located on the bypass pipe 16. Cracked gas from a cracking furnace (not shown) is supplied to PQE 10, SQE 11, and TQE 12 in the direction of the indicator arrow 13.

[0040] A preferred exemplary embodiment of an advantageous quencher system arrangement employing both gas feed and liquid feed modes is described in Figure 4 The diagram is shown schematically. For clarity, PQE 10 is shown schematically. The tube 20 shown, indicated by the arrow, leads from PQE10 and guides the pyrolysis gas into the SQE gas inlet tube 21 of the secondary heat exchanger (SQE11) in the direction of the arrow.

[0041] The horizontally arranged SQE11 is connected in series with a similarly horizontally arranged conveyor heat exchanger 26 for dual operation on the pyrolysis gas side; this conveyor heat exchanger is also referred to as TLX-D 26. The pyrolysis gas to be cooled reaches the SQE gas inlet pipe 21 via the provided pipe 20 and flows through the SQE11 to the SQE gas outlet pipe 23. The pyrolysis gas flows into the TLX-D gas inlet pipe 25 through the arranged TLX-D gas supply pipe 24 and continues to the TLX-D gas outlet pipe 27 in TLX-D 26.

[0042] SQE11 is connected to the steam drum 59 via SQE downpipe 52 and SQE uppipe 57 on the cooling side, water / steam side, or shell side. Natural circulation cooling in SQE11 is achieved through SQE downpipe 52 and SQE uppipe 57.

[0043] Furthermore, the TLX-D 26 is connected to the steam drum 59 via a TLX-D downpipe 38 equipped with a TLX-D downpipe valve 39 and a TLX-D riser 46 equipped with a TLX-D riser valve 47. Natural cooling in the TLX-D 26 is achieved through the TLX-D downpipe 38 and the TLX-D riser 46.

[0044] Furthermore, the TLX-D 26 is connected to a TLX-D feedwater supply pipe 30 equipped with a TLX-D feedwater supply pipe valve 31, and the TLX-D 26 is connected to the steam drum 59 via a feedwater guide pipe 34 equipped with a TLX-D feedwater guide pipe valve 35. Forced cooling circulation in the TLX-D 26 is achieved through the arranged TLX-D feedwater supply pipe 30 and TLX-D feedwater guide pipe 34.

[0045] The SQE11 will no longer be considered further to explain the function of TLX-D 26 in more detail.

[0046] The TLX-D 26 can preferably operate in two different modes. Depending on the pyrolysis gas to be processed, the TLX-D 26 operates as a feedwater preheater in gaseous feed mode, and as an evaporator in liquid feed mode. A more detailed description of these different operating modes has already been given in the background section, and therefore further description is omitted.

[0047] In the gas feed operation mode of TLX-D 26 as a feedwater preheater, TLX-D feedwater supply pipe valve 31 and TLX-D feedwater guide pipe valve 35 are open and TLX-D downpipe valve 39 and TLX-D riser valve 47 are closed; that is, TLX-D downpipe 38 and TLX-D riser 46 are blocked and no longer unobstructed.

[0048] The feedwater or boiler feedwater is supplied via a pump (not shown) through an open TLX-D feedwater supply valve 31 and into the TLX-D26 feedwater inlet pipe 32 of the TLX-D26 via the TLX-D feedwater supply pipe 30. Under counter-current principle, the feedwater flows through the shell side of the TLX-D26 in this manner, i.e., against the flow direction of the gaseous cracked gas, until it reaches the TLX-D feedwater outlet pipe 33. The cracked gas from the TLX-D gas inlet pipe 25, flowing through the TLX-D26 on the pipe side to the TLX-D gas outlet pipe 27, is effectively cooled to a predetermined temperature by the particularly efficient flow guidance of the feedwater flowing through the TLX-D26 under the counter-current principle. The discharged heat is absorbed by the guided feedwater, which is heated from approximately 150°C to approximately 300°C. The heated supply water leaves the TLX-D 26 through the installed TLX-D feedwater outlet pipe 33, and enters the steam drum 59 through the arranged TLX-D feedwater guide pipe 34 and through the opened TLX-D feedwater guide pipe valve 35 and the TLX-D steam drum water supply pipe 36 installed on the steam drum 59.

[0049] In the liquid feed operation mode of the TLX-D 26 operating as an evaporator, the TLX-D downcomer valve 39 and the TLX-D riser valve 47 are open, while the TLX-D feedwater supply pipe valve 31 and the TLX-D feedwater guide pipe valve 35 are closed; that is, the TLX-D feedwater supply pipe 30 and the TLX-D feedwater guide pipe 34 are blocked. Feedwater is supplied to the steam drum 59 through the installed feedwater supply pipe 49 and the feedwater pipe 50 located at the steam drum. In the liquid feed operation mode, the necessary supply water is supplied to the steam drum 59 from an external source. This external supply water has no impact on the operating mode of the TLX-D 26 and is therefore not considered further.

[0050] The TLX-D 26 is integrated into the saturated steam system or cooling system of the quench system. Water from the steam drum 59 flows through the TLX-D downcomer connection pipe 37, through the TLX-D downcomer 38, and then through the open TLX-D downcomer valve 39, until it is distributed to the TLX-D downcomer branches 40, 41, and 42 installed on the TLX-D 26. Water flows from the TLX-D downcomer branches 40, 41, and 42 through the shell side of the TLX-D 26 to the TLX-D riser branches 43, 44, and 45 on the opposite side. As water flows through the TLX-D 26, the cracked gas flowing from the TLX-D gas inlet pipe 25 through the pipe side of the TLX-D 26 to the TLX-D gas outlet pipe 27 is not significantly cooled because the inlet temperature of the cracked gas is close to the saturated steam temperature of the water. Therefore, only a small amount of steam generated on the water side or shell side of the TLX-D 26 enters the steam drum 59 via TLX-D riser branches 43, 44, 45, TLX-D riser 46, and the open TLX-D riser valve 47 and TLX-D steam drum riser 48. Due to its preferred configuration, the TLX-D 26 can operate with very low output. This operating mode avoids cooling of the cracked gas below the condensation temperature, eliminating the need to bypass the conventional TQE.

[0051] The advantages of the preferred exemplary embodiment are based on the fact that costs are significantly reduced by avoiding the gas-side bypass loop and the need for the expensive space associated with it is eliminated.

[0052] Compared to the traditional TQE, the major technical change of the TLX-D 26 is its dual-operation configuration.

[0053] In an exemplary embodiment, the TLX-D feedwater inlet pipe 32 and TLX-D feedwater outlet pipe 33, which are used as feedwater preheaters in gas feed mode, are preferably arranged at TLX-D 26. Furthermore, the TLX-D downpipes 40, 41, 42 and the TLX-D uppipes 43, 44, 45 are each preferably installed at TLX-D 26, which is used as an evaporator in liquid feed mode.

[0054] The horizontally arranged TLX-D 26 has its TLX-D water inlet pipe 32 and TLX-D water outlet pipe 33 located in front of the TLX-D gas outlet pipe 27 and behind the TLX-D gas inlet pipe 25, respectively, on the bottom and top sides of the TLX-D housing 28. Water is supplied through the TLX-D water inlet pipe 32 installed on the bottom side of the TLX-D housing 28, and preheated water is discharged through the TLX-D water outlet pipe 33 located on the top side of the TLX-D housing 28.

[0055] The number and horizontal position of the TLX-D downcomer branches 40, 41, 42 and the TLX-D riser branches 43, 44, 45 are predetermined based on the required steam generation; that is, Figure 4 The number of TLX-D downpipes and TLX-D uppipes shown is adjustable. In this case, water is supplied through TLX-D downpipes 40, 41, and 42 installed on the bottom side of the TLX-D housing 28, and water / steam is discharged through TLX-D uppipes 43, 44, and 45 arranged horizontally on the top side of the TLX-D housing 26.

[0056] The arrangement and position of the baffles 62, which are surrounded by the TLX-D housing 28 of the TLX-D 26 and located within the TLX-D interior 29, are predetermined based on the cooling of the pyrolysis gas in the gas feed mode. The baffles 62 have a special construction, which will be further shown and described below. This arrangement and position of the baffles 62 of the TLX-D 26 is determined by… Figure 5 As shown.

[0057] exist Figure 5The wavy line shown in the top view represents the supply water flow 65 on the shell side in the gas feed mode. The supply water enters the TLX-D 26 through the TLX-D supply water inlet pipe 32 and is deflected 180° by a first baffle 63, located at a predetermined distance from the supply water supply pipe, within the TLX-D interior 29 of the TLX-D, thereby flowing through a free supply water flow zone 60. The cross-section of the free supply water flow zone 60 is visible from point AA and has a maximum height as a function of predetermined process conditions, ranging from 10% to 40% of the diameter of the TLX-D shell 28, preferably from 15% to 25%. Based on a second baffle 64 arranged within the TLX-D interior 29 of the TLX-D 26 and at a predetermined distance from the first baffle 63, the supply water is also deflected 180° and flows through a second free supply water flow zone.

[0058] This process is repeated as a function of the length of TLX-D 26 up to TLX-D feedwater outlet pipe 33. The corresponding length of TLX-D 26 with predetermined precise process conditions is predetermined based on the gas side and the water / steam side. The number of arranged baffles 62 is adjustable as a function of predetermined process conditions. The distance between each baffle is in the range of approximately 100 mm to 600 mm, preferably in the range of 300 mm to 500 mm.

[0059] exist Figure 5 The arrows shown in the side view indicate the water / vapor flow 66 on the shell side in the liquid feed mode. Water enters the horizontally arranged TLX-D 26 on the shell side through the TLX-D downpipes 40, 41, 42 and passes vertically through the TLX-D. As the water passes vertically through the TLX-D 26, a partial phase change occurs. Therefore, in addition to water, a vapor component is present. Thus, the generated steam can be ensured to be discharged through the TLX-D uppipes 43, 44, 45. Therefore, the baffle 62 has a flattened structure in the upper region. As a result, the generated steam flows into the free volume or steam space 61 formed below the TLX-D uppipes 43, 44, 45 and is discharged through the TLX-D uppipes 43, 44, 45.

[0060] When the free volume or steam space 61 or the baffle 62 is flattened, it is possible to consider making the flattened end of the baffle very small so that no undesirable bypass flow occurs during operation of the TLX-D26 as a feedwater preheater in gas feed mode, and on the other hand, making the flattened end of the baffle very large so that the generated steam can be completely discharged during operation of the TLX-D as an evaporator in liquid feed mode. The maximum height of the flattened end cross-section is configured in the range of about 5 mm to 40 mm, and preferably in the range of 10 mm to 15 mm.

[0061] The variations in the number and location of the TLX-D downpipes and uppipes, as well as the baffle design, are crucial for the reliable operation of the TLX-D 26 in dual-operation mode. Therefore, when configuring the TLX-D 26, predefined machining conditions are considered in a precise manner.

Claims

1. A quench system for equipment used in processing pyrolysis furnaces employing liquid and gaseous feedstocks, comprising a primary heat exchanger (10), a secondary heat exchanger (11), and a tertiary heat exchanger (12) connected in series, characterized in that, The conveyor heat exchanger (26) for dual operation is arranged and configured as a three-stage heat exchanger. The conveyor heat exchanger (26) is connected in series to the secondary heat exchanger (11) via the conveyor heat exchanger gas feed pipe (24). The conveyor heat exchanger (26) is connected to the steam drum (59) connected to the feed water supply pipe (49) via the conveyor heat exchanger water guide pipe (34), the conveyor heat exchanger riser pipe (46), and the conveyor heat exchanger downpipe (38). The secondary heat exchanger (11) is connected to the steam drum (59) connected to the feed water supply pipe (49) via the secondary heat exchanger downpipe (52) and the secondary heat exchanger riser pipe (57). The conveyor heat exchanger (26) is equipped with a conveyor heat exchanger water supply pipe (30) with a conveyor heat exchanger water supply pipe valve (31). The conveyor heat exchanger water guide pipe (34) is equipped with a conveyor heat exchanger water guide pipe. Valves (35), conveyor heat exchanger downcomer valve (39) installed on conveyor heat exchanger downcomer, conveyor heat exchanger upcomer valve installed on conveyor heat exchanger upcomer (46), wherein natural circulation cooling in conveyor heat exchanger (26) is carried out through conveyor heat exchanger downcomer (38) and conveyor heat exchanger upcomer (46), conveyor heat exchanger (26) is connected to a provided conveyor heat exchanger feed water supply pipe (30) equipped with conveyor heat exchanger feed water supply pipe valve (31), conveyor heat exchanger (26) is connected to steam drum (59) through an arranged conveyor heat exchanger feed water guide pipe (34) equipped with conveyor heat exchanger feed water guide pipe valve (35), wherein forced circulation cooling in conveyor heat exchanger (26) is carried out through the arranged conveyor heat exchanger feed water supply pipe (30) and conveyor heat exchanger feed water guide pipe (34);The conveyor heat exchanger (26) has several baffles (62) arranged at a certain distance from each other. The baffles (62) are arranged inside the conveyor heat exchanger (29) surrounded by the conveyor heat exchanger housing (28) and are perpendicular to the center line (67) of the conveyor heat exchanger (26) in the horizontal position. The arrangement and position of the baffles (62) are predetermined based on the additional steam generated in the liquid feed mode. The baffles (62) arranged in the conveyor heat exchanger (26) and perpendicular to the center line (67) of the conveyor heat exchanger are used when water flows through the conveyor heat exchanger in the horizontal position. The upper region has a flat structure, and the free volume or steam space (61) is arranged below the rising branch pipes (43, 44, 45) of the conveyor heat exchanger. The flat end of the baffle (62) ensures that, on the one hand, no unwanted bypass flow occurs during the operation of the conveyor heat exchanger (26) as a feedwater preheater in gas feed mode, and on the other hand, the flat end of the baffle (62) is configured to completely discharge the generated steam during the operation of the conveyor heat exchanger (26) as an evaporator in liquid feed mode. The maximum height of the flat end is configured in the range of 5 mm to 40 mm.

2. The quench system according to claim 1, characterized in that, The maximum height of the flat end is configured in the range of 10mm to 15mm.

3. The quench system according to claim 1 or 2, characterized in that, A first baffle (63) is installed inside the conveyor heat exchanger (29) of the conveyor heat exchanger (26) and at a predetermined distance from the feed water inlet pipe (32) of the conveyor heat exchanger. The first baffle (63) deflects the supply water flow on the shell side by 180° and has a free supply water flow cross section (60). Its maximum height is in the range of 10% to 40% of the inner diameter (68) of the conveyor heat exchanger shell as a function of predetermined process conditions. A second baffle (64) is arranged inside the conveyor heat exchanger (29) of the conveyor heat exchanger (26) and at a predetermined distance from the first baffle (63). The second baffle deflects the supply water by 180° and has a free supply water flow cross section (60) as a function of the length of the conveyor heat exchanger (26) until an additional baffle group is provided at the feed water outlet pipe (33) of the conveyor heat exchanger.

4. The quench system according to claim 3, characterized in that, The maximum height, as a function of predetermined process conditions, is in the range of 15% to 25% of the inner diameter (68) of the heat exchanger housing of the delivery line.

5. The quench system according to claim 3, characterized in that, The corresponding lengths of the conveyor heat exchanger (26) with predetermined process conditions are predetermined on the gas side and the water / steam side, and the number of baffles (62) arranged is adjustable as a function of predetermined process conditions, with the distance between each baffle ranging from 100 mm to 800 mm.

6. The quench system according to claim 4, characterized in that, The corresponding lengths of the conveyor heat exchanger (26) with predetermined process conditions are predetermined on the gas side and the water / steam side, and the number of baffles (62) arranged is adjustable as a function of predetermined process conditions, with the distance between each baffle ranging from 100 mm to 800 mm.

7. The quench system according to claim 5 or 6, characterized in that, The distance between each baffle is limited to between 300mm and 600mm.

8. A process for a quench system of a pyrolysis furnace employing liquid and gaseous feedstocks, comprising a primary heat exchanger (10), a secondary heat exchanger (11), and a tertiary heat exchanger (12) connected in series according to claim 1, characterized in that, The conveyor heat exchanger is configured to be connected as a three-stage heat exchanger for dual operation. In the case of gaseous feed, the conveyor heat exchanger (26) operates as a feed water preheater in gas feed mode, and in the case of liquid feed, the conveyor heat exchanger operates as an evaporator in liquid feed mode. In the gas feed mode, the feed water supply pipe valve (31) and feed water guide pipe valve (35) of the conveyor heat exchanger are open, and the downpipe valve (39) and the riser valve (47) of the conveyor heat exchanger are closed.

9. The processing procedure of the quench system according to claim 8, characterized in that, Under the countercurrent principle, the supply water on the shell side is guided in the opposite direction to the flow of the gaseous cracked gas, and the supply water is heated to a predetermined temperature in the delivery line heat exchanger (26) through the open delivery line heat exchanger water supply pipe valve (31).

10. The processing procedure of the quench system according to claim 9, characterized in that, The heat from the pyrolysis gas discharged in the heat exchanger (26) of the delivery line will heat the feed water from 150°C to 300°C.

11. The processing procedure of the quench system according to claim 8, characterized in that, In liquid feeding mode, the downcomer valve (39) and the upcomer valve (47) of the conveyor heat exchanger (26) are opened, the feed water supply pipe valve (31) and the feed water guide pipe valve (35) of the conveyor heat exchanger are closed, and the supply water is guided to the steam drum (59) through the installed feed water supply pipe (49).

12. The processing procedure of the quench system according to claim 11, characterized in that, The conveyor heat exchanger is integrated into the saturated steam system or cooling system of the quench system, wherein water is drawn from the steam drum (59) through the conveyor heat exchanger downcomer (38) and the open conveyor heat exchanger downcomer valve (39) until it is distributed to the conveyor heat exchanger downcomer branches (40, 41, 42) installed on the conveyor heat exchanger.

13. The processing procedure of the quench system according to claim 12, characterized in that, Water from the steam drum (59) flows through the conveyor heat exchanger (26) on the shell side to the conveyor heat exchanger rising branch (43,44,45), which is arranged opposite to the conveyor heat exchanger descending branch (40,41,42), in which the pyrolysis gas passing through the conveyor heat exchanger is not significantly cooled.

14. The processing procedure of the quench system according to claim 13, characterized in that, Due to the special guidance of the water flow, the inlet temperature of the cracked gas in the conveyor heat exchanger (26) reaches the saturated steam temperature, and a small amount of steam is generated on the water side or the shell side of the conveyor heat exchanger shell (28). At the same time, the steam enters the steam drum (59) through the conveyor heat exchanger riser branch (43, 44, 45), through the conveyor heat exchanger riser pipe (46), through the open conveyor heat exchanger riser pipe valve (47) and the conveyor heat exchanger steam drum riser pipe (48).

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