CN222812032U - A cold box system arranged in height direction - Google Patents

Abstract

The present application discloses a cold box system arranged in the height direction, wherein the cold box system is equipped with a heat exchanger and a turbo expander arranged from high to low in the vertical direction, wherein the bottom outlet of the heat exchanger is connected to the top inlet of the turbo expander via a connecting member, wherein a liquid accumulation basin separates the connecting member and the heat exchanger to accommodate leaked liquid of the cold box system. By making full use of the lower space of the heat exchanger cold box, more floor space is saved and installation cost is saved.

Description

Cold box system arranged along height direction

Technical Field

The application belongs to the field of air separation, and relates to a layout of a cold box. And more particularly to a cold box system arranged in a height direction.

Background

Many of the components of the air separation plant operate at low temperatures below-50 ℃ and even below-100 ℃. To be insulated from the atmosphere, these components, such as distillation column(s), heat exchanger(s), condensing evaporator(s), phase separator(s), cryopump/(s) expander(s) and interconnecting piping(s), need to be housed in one or more cold boxes. The cold box is an insulating casing having an outer wall completely surrounding an insulating inner cavity, and a space between the outer wall and the included component is generally filled with an insulating material such as perlite.

As disclosed in chinese patent publication No. CN110662935A, a typical gas production system supplies liquefied gas as a product gas obtained by rectifying a gas source. The first heat exchanger, the turbine expansion, the recycling air source compressor, the high-pressure rectifying tower, the low-pressure rectifying tower and the pressure device are sequentially arranged in the cold box from left to right. In the first heat exchanger, the compressor and the high pressure rectification column, a recycle gas line is formed and the air flow is recycled.

In a typical design, the heat exchanger is close to the tower, which increases the size of the cold box, causing problems associated with transportation restrictions or difficulties. In some conditions, the heat exchanger is required to be positioned at a high vertical height to have a sufficient head in order to reduce the amount of pump usage. If the cold box is arranged in the prior art, more space is required.

Disclosure of utility model

In order to fully utilize the space below the heat exchanger and reduce the occupied area of the cold box area, the application designs a cold box system arranged along the height direction.

The application aims to optimize the arrangement of various components including a cold box and a pipeline in air separation equipment, integrate the pipeline (pipeline) of a turbine expander into a shell at the bottom of the cold box, save construction cost and time, save site occupied area and improve reliability.

In particular, the present application focuses on the configuration of the cold box. By arranging the heat exchangers above the turbo-expander, in sequence in the vertical space, the footprint is further reduced. The valves of the heat exchanger and various pipelines are arranged at different heights.

In order to achieve the above object, the present application discloses a cold box system arranged in a height direction, the cold box system being configured with a heat exchanger and a turbo expander arranged from high to low in a vertical direction, a bottom outlet of the heat exchanger being connected to a top inlet of the turbo expander via a connection member, wherein a liquid collecting basin separates the connection member from the heat exchanger for receiving leakage liquid of the cold box system.

Further, the cold box is a closed square box body formed by welding a steel structure frame and cold box plates around.

Further, the connecting member is an L-shaped sleeve.

Further, a temperature detector is arranged in the effusion pot and used for detecting leakage liquid.

Further, the pipelines passing through the effusion pots are all welded in a sealing way.

Further, a filling pipeline is arranged at the top of each of two sides of the effusion basin.

Further, the height of the filling line is greater than the height of the effusion cell.

Further, the filling line is a perlite filling line.

Further, a purge line is provided at the bottom of the heat exchanger.

Further, the cold box system also includes a stair module that may be attached to the cold box system in the field.

Further, when the cold box system is shipped in two sections, the method for installing the cold box may include installing the bottom cold box section in a vertical orientation, then lifting the top cold box section and placing the top cold box section on top of the bottom cold box section.

Compared with the prior art, the technical scheme provided by the application has the following advantages:

The lower space of the heat exchanger cold box is fully utilized to save more occupied area and installation cost.

Drawings

The advantages and spirit of the present application will be further understood from the following detailed description and the accompanying drawings.

Fig. 1 is a schematic view of a cold box system arranged in the height direction provided by the present application.

In the figure, a heat exchanger 101, a liquid accumulation basin 102, a sleeve 103-L and a turbine expander 104.

Detailed Description

Specific embodiments of the present application are described in detail below with reference to the accompanying drawings. However, the present application should be understood not to be limited to such an embodiment described below, and the technical idea of the present application may be implemented in combination with other known technologies or other technologies having the same functions as those of the known technologies.

In the following description of the specific embodiments, for the sake of clarity in explaining the structure and operation of the present application, description will be given by way of directional terms, but words of front, rear, left, right, outer, inner, outer, inner, axial, radial, etc. are words of convenience and are not to be construed as limiting terms.

In the following description of the specific embodiments, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are merely for convenience in describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and are not to be construed as limiting the present application.

A component or device is "under" another component or device when its top edge is at a lower geodetic level than the bottom edge of the other component.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not intended to be limiting with respect to time sequence, number, or importance, but are not to be construed as indicating or implying a relative importance or implicitly indicating the number of features indicated, but merely for distinguishing one feature from another in the present disclosure. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present application, the meaning of "a plurality" is two or more, unless explicitly specified otherwise. Likewise, the appearances of the phrase "a" or "an" in this document are not meant to be limiting, but rather describing features that have not been apparent from the foregoing. Likewise, unless a particular quantity of a noun is to be construed as encompassing both the singular and the plural, both the singular and the plural may be included in this disclosure. Likewise, modifiers similar to "about" and "approximately" appearing before a number in this document generally include the number, and their specific meaning should be understood in conjunction with the context.

It should be understood that in the present application, "at least one (item)" means one or more, and "a plurality" means two or more. "and/or" is used to describe association of associated objects, and means that three relationships may exist, for example, "a and/or B" may mean that only a exists, only B exists, and three cases of a and B exist simultaneously, where a and B may be singular or plural. The character "/" generally indicates that the context-dependent object is an "or" relationship. "at least one of" or the like means any combination of these items, including any combination of single item(s) or plural items(s). For example, at least one of a, b or c may represent a, b, c, "a and b", "a and c", "b and c", or "a and b and c", wherein a, b, c may be single or plural.

In the present application, the terms "mounted," "connected," "secured," and the like are to be construed broadly, unless otherwise specifically indicated and defined. For example, the components can be fixedly connected, detachably connected or integrated, mechanically connected or electrically connected, directly connected or indirectly connected through an intermediate medium, and can be communicated inside the two components or the interaction relationship of the two components. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances. "fixedly connected" or "non-movably connected" is understood to mean that the connection between two or more structural members is not configured to provide relative movement. One example of a fixed connection is a welded connection or bolted connection, and in some cases a welded seam and bolted connection. "movably connected" or "movable" or "mobile connection" is understood to mean a connection between two or more structural members that allows for horizontal and/or vertical relative movement between the members under extreme dynamic loads. Such a connection typically does not allow movement under static or generally dynamic loads (e.g., as applied from light/medium wind).

The terms "unit", "article", "module" and "module" described in the present specification mean a unit for processing at least one function and operation, and may be implemented by hardware components or software components and combinations thereof.

The term "sealing connection" or "sealable connection" means that the two component containers are connected or connectable by a welded connection, an adhesive connection, a screw thread or other means such that no contents leak out of the multi-chamber mixing container through the sealing connection when pressure is established for evacuating the multi-chamber mixing container.

In the term used herein, a "heat exchanger" is a device designed to indirectly transfer heat between at least two fluid streams, for example, directed in countercurrent relation to each other. Heat exchangers used within the scope of the application may be formed from parts of one or more heat exchangers connected in parallel and/or in series, for example, from one or more plate heat exchanger blocks. However, the application is in principle also applicable to other types of heat exchangers and is not limited to plate heat exchangers. The heat exchanger has "channels" which are configured to conduct a fluid and are separated from the other channels by separating plates or are connected on the inlet side and the outlet side only via respective heads. The channels are separated from the outside by means of side bars. The channels are hereinafter referred to as "heat exchanger channels". According to the conventional terminology, the terms "heat exchanger", "heat transfer device", "heat exchange device" are used synonymously hereinafter. This also applies to the terms "heat exchange" and "heat transfer". In a typical air separation plant, a main heat exchanger is used to cool a plurality of feed air streams by indirect heat exchange with a return stream from a separation column. In its construction, the side into which the higher temperature stream, such as the feed air stream, is fed is referred to as the warm side, and the side into which the lower temperature stream, such as the return stream from the separation column, is fed is referred to as the cold side. Typically, the hot and cold ends are located opposite on the main heat exchanger. For example, the heat exchanger is installed vertically with the hot side up and the cold side down.

The means for delivering/introducing these streams include the necessary piping, pressure relief or expansion devices, and connection ports.

As used herein, a "cold box" is understood to be an insulated enclosure that completely encloses an insulated interior in an outer wall, with the equipment components to be insulated disposed therein, such as one or more separation columns and/or heat exchangers. The insulating effect may be achieved by suitably designing the outer wall and/or by filling the gap between the device part and the outer wall with an insulating material. The latter form preferably employs a powdered material, such as perlite. Not only are the tower and heat exchanger enclosed within the cold box, but other cold plant components are also enclosed by one or more cold boxes, which at the same time can cause the volume of the cold box to become quite large.

In the case of prefabricated units, the external dimensions of the cold box determine the transport dimensions of the packages. The "height" of the cold box is understood to mean the dimension in the vertical direction during operation of the device, based on the orientation of the cold box, and the "cross section" is the area perpendicular thereto (horizontal). The longitudinal axis of the cold box and tower is the axis parallel to the height. In transit, the cold box is shipped in a horizontal fashion, so the height of the cold box determines the length in transit, while the cross-section determines the height and width in transit.

Each aspect or embodiment defined herein may be combined with any other aspect or embodiment unless clearly indicated to the contrary. In particular, any feature indicated as being preferred or advantageous may be combined with any other feature or features indicated as being preferred or advantageous.

Specific embodiments of the present application are described in detail below with reference to the accompanying drawings.

Example 1

A typical cryocooler is disposed in the cold box and includes a working circuit. The working circuit forms a loop and contains a working fluid, the working circuit forming a cycle comprising, in series, means for compressing the working fluid, means for cooling the working fluid, means for expanding the working fluid, and means for heating the working fluid.

The cryorefrigeration device comprises a heat exchanger intended to extract heat at least one component by heat exchange with the working fluid circulating in the working circuit, while the component for expanding the working fluid comprises at least one turboexpander.

When the cryocooler is operating, the temperature of the heat exchanger equalizes along a longitudinal gradient between the cold and hot ends. The inlet of the turboexpander receives the working fluid from the heat exchanger.

The heat exchanger cold box is a sealed square box body formed by welding a steel structure frame and cold box plates around, an aluminum plate heat exchanger and an expansion end of a turbine expander are arranged in the heat exchanger cold box, and heat preservation materials such as pearlitic sand and the like are filled in the heat exchanger cold box.

The components are connected through pipelines. The pipeline connected with the cold box is a low-temperature pipeline, cold insulation measures of the pipeline are needed to be considered, the pipeline in the cold box is in a low-temperature state, and besides the low-temperature resistance of the pipeline, the stress effect of the low-temperature pipeline is also needed to be considered.

Fig. 1 shows a schematic view of the cold box area in this embodiment.

In the vertical direction, the heat exchanger 101 is disposed at a high level, and the turbo-expander 104 is disposed at a low level. A vertical L-shaped sleeve 103 connects the heat exchanger 101 and the turbo-expander 104.

For example, liquid leaking within the cold box near the top may contact insulating (adiabatic) material (e.g., perlite) causing the perlite to freeze, which reduces shrinkage and expansion of the pipes penetrating the top and/or potentially increases the weight of the pipes and the pipes or instrumentation tubes near or below the frozen layer. Embodiments of the present application reduce and/or eliminate these problems.

A liquid basin 102 for containing liquid that may leak separates the L-shaped sleeve 103 from the heat exchanger 101. All lines through the basin 102 require a seal weld. This effectively avoids the risk of damaging surrounding equipment by leaking liquid from the heat exchanger.

The effusion pot 102 serves as a leakage discharge detection means that can detect whether or not there is a leakage phenomenon of liquid (cold liquid) therein. For example, a temperature detector may be used to detect cold fluid leaks. When the ultralow temperature liquid in the cold box leaks, the leaked cold liquid flows downwards into the effusion pot 102. The temperature detector can timely detect the temperature change of the bottom end inside the effusion basin 102, so that leakage can be found rapidly, and the risk of collapse of the cold box caused by a cold liquid brittle steel structure is reduced. Meanwhile, the leakage signal can be transmitted to the corresponding controller to trigger an alarm.

When being connected with the heat exchanger 101, all the pipelines passing through the effusion pot 102 are welded in a sealing way due to the existence of the effusion pot 102. While the top of the line through the effusion cell 102 needs to be spaced from the top cold box, insulation such as perlite is difficult to fill from the top of the heat exchanger cold box as is conventional in the art. To solve the perlite filling problem, a dedicated perlite filling line is added in this embodiment.

Illustratively, perlite fill lines may be provided on top of each of the two sides of the effusion pot 102, with corresponding openings being provided in the effusion pot 102 in accordance with the size of the perlite fill lines. Perlite filler lines are welded to these openings through the heat exchanger 101 with flanges and blind plates at the ends. And for safety reasons, the bottom of the heat exchanger 101 is provided with a purging pipeline, which can be used for filling perlite in the construction stage, and purging after filling, and can ensure that the perlite can pass through the L-shaped sleeve 103 compactly and uniformly.

Preferably, the perlite fill lines are stainless steel lines having a height of Yu Ji a height of the basin 102.

The stainless steel tubing is sealed to the opening in the effusion cell 102. This design allows perlite to pass through and continue to fill the lower low-lying pipe while avoiding the risk of cryogenic liquid leaking from the opening into the lower pipe.

The two stainless steel pipelines are vertically arranged and can be externally arranged on one side of the cold box system, so that operators can fill perlite in batches, and time is saved. Or may be built into the interior of the cold box, the perlite may be more easily moved from top to bottom. The perlite filling line described above allows the physically isolated cold box of the lower section to be densely and evenly filled with perlite, thereby ensuring good insulation of the lower section.

In this embodiment, the cold box system may further comprise a stair module that may be attached to the cold box system in the field.

In this embodiment, a method for installing a cold box when the cold box is shipped in two sections may include installing a bottom cold box section in a vertical orientation, then lifting a top cold box section and placing the top cold box section on top of the bottom cold box section. In one embodiment, instead of welding the two sections together, the two sections may be bolted together. Bolting the two cold box sections together rather than welding greatly reduces field time and necessary equipment.

In this embodiment, the cold box system may include pre-installed platforms that are positioned in a location that is operable to allow a user to access the pre-assembled piping. In the case of two cold boxes placed side by side, this advantageously provides access space and working space for workers to connect pipes from one cold box to another without the expense and time to construct temporary scaffolding as is conventional.

In this embodiment, it is also possible to bolt the top cold box assembly to the bottom cold box assembly at the installation site while still in the horizontal position, and then raise the entire cold box assembly in one piece to the vertical position.

The preferred embodiments of the present application have been described in the specification, and the above embodiments are merely for illustrating the technical solution of the present application and not for limiting the present application. All technical solutions that can be obtained by logic analysis, reasoning or limited experiments according to the inventive concept by those skilled in the art shall be within the scope of the present application.

Claims (10)

1. A cold box system arranged in a height direction, characterized in that the cold box system is provided with a heat exchanger and a turbo expander arranged vertically from high to low, the bottom outlet of the heat exchanger being connected to the top inlet of the turbo expander via a connecting member, wherein a liquid collecting basin separates the connecting member from the heat exchanger for receiving leakage liquid of the cold box system.

2. The cold box system of claim 1, wherein the cold box system is a closed square box body formed by welding a steel structural frame and cold box plates around.

3. The cold box system of claim 1, wherein the connecting member is an L-shaped sleeve.

4. The cold box system of claim 1, wherein a temperature detector is mounted within the effusion cell for detecting leaking liquid.

5. The cold box system of claim 1, wherein the lines through the effusion cell are all sealed by welding.

6. The cold box system of claim 1, wherein a fill line is provided at the top of each of the two sides of the effusion cell.

7. The cold box system of claim 6, wherein the fill line has a height that is greater than a height of the effusion cell.

8. The cold box system of claim 6, wherein the fill line is a perlite fill line.

9. The cold box system of claim 1, wherein a purge line is provided at the bottom of the heat exchanger.

10. The cold box system of claim 1, further comprising a stair module that may be attached to the cold box system in the field.