Vertical heat exchanger

Abstract

A vertical heat exchanger comprises a shell, an upper tube box and a lower tube box. An upper condensed fluid inlet and a lower condensed fluid outlet are respectively formed in the shell, and a spiral wound tube bundle is arranged in the shell. The spiral wound tube bundle is composed of multiple layers of spiral wound tubes, and the spiral directions of the adjacent layers are opposite. And each layer of spiral wound tube forms a tube pass flow channel. The tube pass flow channel is provided with a flow channel outlet formed by the upper free flexible tube end and a flow channel inlet formed by the lower free flexible tube end. And the upper tube box and the lower tube box are detachably fixed with the shell respectively. A fluid seal is formed between the housing and each channel to prevent condensed fluid from entering the corresponding channel from the housing. A tube plate is arranged in each tube box, and the upper free flexible tube end of each layer of spiral wound tube is fixed on the upper tube plate and is opened in the corresponding tube box. And the upper tube box and the lower tube box are respectively provided with a boiling medium outlet and a boiling medium inlet. The vertical heat exchanger is high in heat exchange efficiency, not prone to scaling and simple and firm in structure.

Description

TECHNICAL FIELD

[0001] The utility model relates to a kind of heat exchange equipment. BACKGROUND

[0002] Heat exchanger, such as spiral pipe heat exchanger, can be applied to, for example: methanol wash section in synthetic ammonia device of chemical fertilizer;Distillation reflux system;Concentration system;Rectification system;Tail gas waste heat recovery system;Traditional Chinese medicine extraction system;High-temperature instantaneous sterilization system;CIP cleaning system;Civil heating and ventilation system;Process material heating and cooling, etc. In addition, such heat exchanger can process multiple media simultaneously, especially suitable for being applied to the place needing to transfer larger heat under small temperature difference and the operating pressure of medium in pipe is higher, such as heat exchange equipment used in oxygen production and other low-temperature processes;In addition, it can also be widely applied to supercooler and liquefier of large air separation device (such as liquid oxygen, liquid ammonia device, etc.).

[0003] However, the structure design of existing heat exchanger is usually more complex, the service life is limited, and the overall heat exchange efficiency needs to be further improved. INVENTION CONTENTS

[0004] The utility model aims at providing a vertical heat exchanger, which can at least improve overall heat exchange efficiency and has simple and reliable structure.

[0005] The vertical heat exchanger provided by the utility model comprises:

[0006] A shell, wherein the shell is provided with a condensing fluid inlet located at the upper part and a condensing fluid outlet located at the lower part, respectively, and the shell is internally provided with a spiral wound tube bundle, wherein the spiral wound tube bundle is composed of multiple layers of spiral wound tubes from inside to outside, the spiral directions of the spiral wound tubes of each adjacent layer are opposite, each layer of spiral wound tube forms a tube pass flow channel, the tube pass flow channel has a flow channel outlet formed by the upper free flexible tube end and a flow channel inlet formed by the lower free flexible tube end,

[0007] An upper tube box located above the shell and detachably fixed together with the shell, wherein the shell and the upper tube box form fluid seal to prevent condensing fluid from entering the upper tube box from the shell, the upper tube box is internally provided with an upper tube plate, the upper free flexible tube end of each layer of spiral wound tube is fixed to the upper tube plate and opened in the interior of the upper tube box from the upper tube plate, and the upper tube box is further provided with a boiling medium outlet at the top;And

[0008] A lower tube box located below the shell and detachably fixed together with the shell, wherein the lower tube box also forms fluid seal with the shell to prevent condensing fluid from entering the lower tube box from the shell, the lower tube box is internally provided with a lower tube plate, the lower free flexible tube end of each layer of spiral wound tube is fixed to the lower tube plate and opened in the interior of the lower tube box from the lower tube plate, and the lower tube box is further provided with a boiling medium inlet at the bottom.

[0009] According to one preferred embodiment of the vertical heat exchanger of the present application, the helically wound tubes of each adjacent layer can be separated from each other by gaskets. The gaskets are designed to control the helical pitch angle of the helically wound tubes on one hand, and to increase the disturbance of the shell side flow on the other hand.

[0010] According to another preferred embodiment of the vertical heat exchanger of the present application, a tube bundle centering rod can be further arranged inside the shell, and the helically wound tubes of each layer of the helically wound tube bundle are arranged around the tube bundle centering rod. The outer diameter of the tube bundle centering rod can be adapted to the minimum bending radius of the helically wound tubes, and serves as a support during manufacturing.

[0011] According to yet another preferred embodiment of the vertical heat exchanger of the present application, a lifting lug seat can be further arranged outside the shell. The arrangement of the lifting lug seat can facilitate the vertical placement of the heat exchanger or the moving and maintenance operation thereof.

[0012] According to the vertical heat exchanger of the present application, the fluid flows in a helical manner inside the heat exchange tubes, forming secondary flow between the flow passages, thereby strengthening the heat exchange effect. Meanwhile, the shell side fluid also forms turbulent flow between each layer of the helically wound tubes, reducing the adhesion of the fluid to the wall surface and making it less prone to fouling.

[0013] In summary, the vertical heat exchanger of the present application has good turbulent flow effect, high heat exchange efficiency, low impurity deposition probability and low tendency to fouling, and has simple and reliable structure. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 It is an overall structural schematic view of the vertical heat exchanger of the present application. DETAILED DESCRIPTION

[0015] The present application will be further described below with reference to the accompanying drawings.

[0016] Figure 1 It is an overall structural schematic view of the vertical heat exchanger of the present application. As shown in Figure 1 the vertical heat exchanger of the present application generally comprises: a shell 10, a helically wound tube bundle 20 fixed in the shell 10, an upper tube box 30 and a lower tube box 40.

[0017] The shell 10 is provided with a lateral condensing fluid inlet 11 at the upper portion and a lateral condensing fluid outlet 12 at the lower portion, and the condensing fluid flows into the shell 10 from the lateral condensing fluid inlet 11 and flows out of the shell 10 from the lateral condensing fluid outlet 12.

[0018] The top and bottom of the shell 10 are provided with an upper flange plate 13 and a lower flange plate 14, respectively. The middle portion of the outer side of the shell 10 is further provided with a lifting lug seat 15, so as to facilitate the vertical placement of the heat exchanger or the moving and maintenance operation thereof.

[0019] A spiral wound tube bundle 20 is fixedly arranged inside the shell 10. The spiral wound tube bundle 20 is composed of multiple layers of spiral wound tubes arranged from inside to outside, such as the outermost spiral wound tube 22 and the next outer spiral wound tube 23 shown in the figure.

[0020] A support tube bundle center (not specifically shown in the figure) can also be arranged inside the shell 10 along the center line 21 thereof, and the spiral wound tubes of each layer of the spiral wound tube bundle 20 are arranged around the support tube bundle center. In addition, although not specifically shown, the spiral wound tubes of each adjacent layer can be separated from each other by a gasket. A corresponding profiled gasket can be used to control the spiral angle of the spiral wound tubes.

[0021] The spiral directions of the spiral wound tubes of each adjacent layer are opposite to each other, and each layer of spiral wound tube forms a tube pass flow channel having a flow channel outlet formed by the upper free flexible tube end and a flow channel inlet formed by the lower free flexible tube end. For example, the outermost spiral wound tube 22 has a lower free flexible tube end 220 and an upper free flexible tube end 221, the next outer spiral wound tube 23 has a lower free flexible tube end 230 and an upper free flexible tube end 231, and so on.

[0022] Such free flexible tube ends of the spiral wound tubes can self-compensate the expansion and contraction length caused by thermal expansion and contraction over a certain length. Such flexible free end design helps to reduce the stress impact on the spiral wound tubes when they are fixed to the tube plate and also reduces the possibility of leakage between the two.

[0023] An upper tube box 30 is arranged above the shell 10 and has a flange plate 33 at the bottom. Therefore, the upper tube box 30 can be detachably fixed to the shell 10 through detachable connection between the flange plate 33 and the upper flange plate 13, and a fluid seal can be formed therebetween to prevent condensed fluid from entering the upper tube box 30 from the shell 10. Such detachable connection is particularly convenient for descaling operation.

[0024] An upper tube plate is arranged near the position 31 in the upper tube box 30, and the upper free flexible tube end of each layer of spiral wound tube is fixed to the upper tube plate and opens to the inside of the upper tube box 30 there. A boiling medium outlet 32 is further arranged at the top of the upper tube box.

[0025] A lower tube box 40 is arranged below the shell 10 and has a flange plate 43 at the top. Therefore, the lower tube box 40 can be detachably fixed to the shell 10 through detachable connection between the flange plate 43 and the lower flange plate 14, and a fluid seal can be formed therebetween to prevent condensed fluid from entering the lower tube box 40 from the shell 10.

[0026] A lower tube plate is arranged near the position 41 in the lower tube box 40, and the lower free flexible tube end of each layer of spiral wound tube is fixed to the lower tube plate and opens to the inside of the lower tube box 40 there. A boiling medium inlet 42 is further arranged at the bottom of the lower tube box 40.

[0027] According to the vertical heat exchanger, the condensing fluid (steam) flows outside the spiral winding pipe from top to bottom, and the condensing liquid film is effectively thinned and uniformly dispersed by disturbing flow through each layer of spiral winding pipe and the corresponding gasket strip.

[0028] Due to the adjacent spiral winding pipes being reversely wound, the flow of the fluid in the pipe is greatly disturbed, and the fluid in the shell flow forms strong turbulent flow; the fluid in the pipe flows in a spiral state, thereby enhancing the heat exchange effect, so that the heat transfer film coefficient of the tube flow is increased; in addition, the shell flow is continuously disturbed by the pipe bundle outer contour and the gasket strip. Due to the combined influence of the above factors, compared with the general structure of the tube and shell type or spiral pipe type heat exchanger, the heat transfer performance is significantly improved. For example, the total heat transfer coefficient of the heat exchanger commonly used for gas phase heat exchange can only reach 75-365 W / (m2 K), and the total heat transfer coefficient of the vertical heat exchanger of the utility model can be as high as 500 W / (m2 K) or more.

[0029] In addition, compared with the traditional horizontal heat exchanger, the structure of the utility model is more simple and firm, and the failure rate is low, and the service life is longer. In addition, compared with the straight pipe spiral heat exchange pipe, the heat exchange pipe length of the utility model is much longer, and the heat transfer area is significantly increased.

[0030] In addition, each layer of spiral winding pipe can also form two or more tube flow channels to adapt to more medium flow heat exchange.

Claims

1. A vertical heat exchanger, characterized in that, include: The shell has an upper condensate inlet and a lower condensate outlet. Inside the shell are a helical tube bundle and a central tube bundle. The helical tube bundle consists of multiple layers of helical tubes arranged from the inside out. Each layer of helical tubes is arranged around the central tube bundle, and adjacent layers are separated by spacers with opposite helical directions. Each layer of helical tubes forms a tube-side flow channel with an outlet formed by the upper free flexible tube end and an inlet formed by the lower free flexible tube end. An upper tube box is located above the shell and detachably fixed to it, wherein a fluid seal is formed between the shell and the upper tube box to prevent condensate from entering the upper tube box from the shell. An upper tube sheet is installed inside the upper tube box, and the upper free flexible tube ends of each layer of spirally wound tubes are fixed to the upper tube sheet and thus open into the interior of the upper tube box. A boiling medium outlet is also provided at the top of the upper tube box; and The lower tube box is located below the shell and is detachably fixed to the shell. The lower tube box also forms a fluid seal with the shell to prevent condensate from entering the lower tube box from the shell. The lower tube box is equipped with a lower tube sheet. The lower free flexible tube end of each layer of spiral wound tube is fixed to the lower tube sheet and thus opened to the inside of the lower tube box. The bottom of the lower tube box is also equipped with a boiling medium inlet.

2. The vertical heat exchanger according to claim 1, characterized in that, Lifting lugs are also provided on the outside of the shell.

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