CN111912253A

CN111912253A - Multi-strand flow wound tube heat exchanger with tube pass capable of being cleaned on line

Info

Publication number: CN111912253A
Application number: CN202010512638.9A
Authority: CN
Inventors: 吕剑超; 王亚东; 杜涛; 郑志斌; 方剑杰
Original assignee: Zhejiang Petroleum and Chemical Co Ltd
Current assignee: Zhejiang Petroleum and Chemical Co Ltd
Priority date: 2020-06-08
Filing date: 2020-06-08
Publication date: 2020-11-10

Abstract

The invention discloses a multi-strand winding pipe heat exchanger with pipe passes capable of being cleaned on line, which comprises an upper pipe box, a middle barrel and a lower pipe box, wherein a first pipe plate and a second pipe plate divide the inner cavity of the middle barrel into the upper barrel, a columnar pipe box and the lower barrel, a porous plate is connected in the pipe box and divides the pipe box into an upper space and a lower space, a distributor is arranged in the upper space, a nozzle is connected on the distributor, a demineralized water inlet pipe is connected on the outer wall of the middle barrel, a bubble cap plate is arranged in the lower space, pipelines are arranged in the upper barrel and the lower barrel, the upper pipe box is communicated with the upper space through the pipeline in the upper barrel, the lower pipe box is communicated with the lower space through the pipeline in the lower barrel, the upper end wall and the lower end wall of the upper barrel are respectively communicated with a cold medium outlet and a cold medium inlet, the upper end wall and the lower end wall of the lower barrel are respectively communicated with a, the on-line cleaning device can be used for on-line cleaning, and can avoid the problem of amine liquid crystallization caused by the winding pipe heat exchanger in the use process.

Description

Multi-strand flow wound tube heat exchanger with tube pass capable of being cleaned on line

Technical Field

The invention relates to a wound tube heat exchanger, in particular to a multi-strand wound tube heat exchanger with tube passes capable of being cleaned on line, and belongs to the field of petrochemical industry.

Background

The winding pipe heat exchanger is widely applied to devices such as chemical fertilizers, air separation, LNG liquefaction and the like due to the compact structure and high heat exchange efficiency, the application in a hydrogenation device is gradually increased in recent years, the winding pipe heat exchanger is more applied to a hydrogenation reaction product-hydrogenation feeding heat exchange system in the hydrogenation device, the winding pipe heat exchanger can be adopted to greatly improve the heat exchange efficiency, reduce the consumption of fuel gas and reduce the production cost, but in practical application, the winding pipe heat exchanger also has some defects: ammonium chloride and ammonium bisulfide in hydrogenation reaction products can form crystals in a low-temperature section in a heat exchanger, and the conventional winding pipe heat exchanger has a complex structure and cannot be cleaned on line, so that once ammonium salt crystals are generated in the heat exchanger, the heat exchange efficiency is reduced, the system pressure drop is increased, the energy consumption of the device is increased, even the device is forced to be shut down, the device is not favorable for safe and stable operation, and the production cost is increased. Chenzhanhua [ analysis and countermeasure of ammonium salt crystallization of a hydrogenation device wound tube type heat exchanger, J, petrochemical corrosion prevention and protection, No. 33 No. 4 of 2016 ], explains that a certain hydrogenation device wound tube type heat exchanger is forced to be shut down and cleaned due to the fact that the energy consumption is greatly increased due to reduction of ammonium salt crystallization heat exchange efficiency, and in order to avoid recrystallization of the heat exchanger, a method for adjusting a heat exchange network to improve the temperature of a reaction product after heat exchange is adopted, so that the method also causes certain increase of device energy consumption.

Chinese patent document CN201822180841.1 discloses a back-blowing system for preventing the fouling of a coiled tube heat exchanger, which utilizes a nitrogen back-blowing system to blow off the fouling adhered to the tube wall of the coiled tube heat exchanger at regular time, but the method can not be applied to a hydrogenation device, Chinese patent document CN201610331183.4 discloses an easy-to-clean coiled tube heat exchanger, which utilizes ultrasonic waves to automatically clean the interior of a cylinder body and the interior of a spiral tube bundle of the heat exchanger, but because the adhesive force of ammonium salt crystallization and the combination of the equipment inner surface is higher, the method has limited cleaning effect on ammonium salt and can not be generally applied to the hydrogenation device, so that the research and development of the coiled tube heat exchanger have the inevitable trend of being applicable to the hydrogenation device for processing high-nitrogen high-chlorine raw oil, breaking through the bottleneck of temperature limitation of reaction products after heat exchange in the design of a heat exchange network, greatly improving the applicability of the coiled tube heat exchanger in the hydrogenation device, has great practical significance.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides the multi-strand wound tube heat exchanger with the tube side capable of being cleaned on line, which has the technical characteristics that the wound tube heat exchanger can be cleaned on line, the crystallization of amine salt can be avoided in the using process of the wound tube heat exchanger, and the like.

In order to achieve the purpose, the invention is realized by the following technical scheme:

a multi-strand winding pipe heat exchanger with a pipe pass capable of being cleaned on line comprises a barrel, wherein an upper pipe plate and a lower pipe plate are connected in the barrel and divide the interior of the barrel into an upper pipe box, a middle barrel and a lower pipe box, the middle barrel is internally connected with a first pipe plate and a second pipe plate, the first pipe plate and the second pipe plate divide the inner cavity of the middle barrel into the upper barrel, a columnar pipe box and the lower barrel from top to bottom, a perforated plate is connected in the pipe box and divides the pipe box into an upper space and a lower space, an annular tubular distributor is arranged in the upper space and is connected with a plurality of nozzles, a demineralized water inlet pipe is connected to the outer wall of the middle barrel and extends into the upper space to be communicated with the distributor, and a foam cap plate is connected in the lower space;

the upper barrel and the lower barrel are internally provided with pipelines, the upper tube box is communicated with the upper space through the pipeline in the upper barrel, the lower tube box is communicated with the lower space through the pipeline in the lower barrel, the side wall of the upper end of the upper barrel and the side wall of the lower end of the upper barrel are respectively communicated with a first cold medium outlet and a first cold medium inlet, the side wall of the upper end of the lower barrel and the side wall of the lower end of the lower barrel are respectively communicated with a second cold medium outlet and a second cold medium inlet, the upper end of the upper tube box is communicated with a hot medium inlet, and the lower end of the lower tube box is communicated with a hot medium.

As an improvement, the demineralized water inlet pipe is connected with a water supply pipeline through a flange, the water supply pipeline is connected with a valve, a flowmeter and a pressure gauge, the valve comprises a regulating valve, a hand valve and a one-way valve, and the space outside the inner pipelines of the upper cylinder and the lower cylinder forms a shell pass of the heat exchanger.

As an improvement, a first central tube and a second central tube are respectively arranged in the upper barrel and the lower barrel, two ends of the first central tube are respectively connected to the upper tube plate and the first tube plate, two ends of the second central tube are respectively connected to the lower tube plate and the second tube plate, and through holes are formed in the upper tube plate, the lower tube plate, the first tube plate and the second tube plate;

the upper end of the pipeline in the upper barrel body is inserted into the through hole of the upper tube plate to be communicated with the upper tube box, the lower end of the pipeline extends downwards and forms a spiral shape around the first central tube, and the lower end of the pipeline is inserted into the through hole of the first tube plate to be communicated with the upper space;

the upper end of the pipeline in the lower barrel body is inserted into the through hole of the second tube plate to be communicated with the lower space, the lower end of the pipeline extends downwards and forms a spiral shape around the second central tube, and the lower end of the pipeline is inserted into the through hole of the lower tube plate to be communicated with the lower tube box;

the upper pipe box and the upper space and the lower pipe box and the lower space are connected through pipelines to form a heat exchanger tube pass.

As an improvement, a plurality of through holes with the same number are respectively formed in the upper tube plate, the lower tube plate, the first tube plate and the second tube plate, the through holes of the upper tube plate are surrounded into a circular structure, the through holes of the first tube plate are in one-to-one correspondence with the through holes of the upper tube plate from top to bottom, a pipeline is inserted into each through hole of the upper tube plate, and the pipelines surround the first central tube in sequence and in the same direction to form a layer of spiral tube bundle to cover the first central tube;

the through holes of the second tube plate are surrounded into a pattern structure, the through holes of the lower tube plate are in up-down one-to-one correspondence with the through holes of the second tube plate, a pipeline is inserted into each through hole of the second tube plate, and the pipelines surround the second central tube in sequence and the same direction to form a layer of spiral tube bundle to cover the second central tube.

As an improvement, through holes on the upper tube plate and the second tube plate are encircled into three concentrically arranged circles, pipelines on the upper tube plate and in the same circular upper through hole surround the first central tube in sequence and in the same direction to form a layer of spiral tube bundle, a first cushion block is arranged between adjacent layers of spiral tube bundles for spacing, a second cushion block is arranged between the innermost layer of spiral tube bundle and the first central tube, and the spiral directions of the adjacent layers of spiral tube bundles are opposite;

the pipeline in the same circular upper through hole on the second tube plate surrounds the second central tube in sequence and in the same direction to form a layer of spiral tube bundle, a first cushion block is arranged between adjacent layers of spiral tube bundles for spacing, a second cushion block is arranged between the innermost layer of spiral tube bundle and the second central tube, and the spiral directions of the two adjacent layers of spiral tube bundles are opposite.

As an improvement, the first central tube and the middle cylinder body and the second central tube and the middle cylinder body are coaxial.

As an improvement, the side walls of the lower ends of the upper cylinder and the lower cylinder are also communicated with a shell pass liquid discharge port to prevent moisture from gathering at the lower part of the shell pass of the heat exchanger to generate wet hydrogen sulfide corrosion.

As an improvement, the first cold medium outlet and the first cold medium inlet are respectively positioned on the left side surface and the right side surface of the upper cylinder, and the second cold medium outlet and the second cold medium inlet are respectively positioned on the left side surface and the right side surface of the lower cylinder.

As an improvement, the distributors are provided with a plurality of distributors, the volumes of the distributors are gradually reduced, the distributors are sequentially sleeved with a plurality of layers of concentric circles, adjacent distributors are communicated, and the brine inlet pipe extends into the upper space and is communicated with the outermost distributor.

As a refinement, there are 2 distributors.

Has the advantages that: the online cleaning is realized, the energy consumption is prevented from rising and even forced shutdown caused by the generation of amine salt crystallization in the use process of the winding tube heat exchanger, the raw material adaptability of the hydrogenation device adopting the winding tube heat exchanger is greatly improved, and the bottleneck that the temperature is limited after the heat exchange of reaction products in the heat exchange network design of the hydrogenation device adopting the winding tube heat exchanger can be broken through.

Drawings

Fig. 1 is a schematic view of the overall structure of the present invention.

FIG. 2 is a cross-sectional view taken at A-A of the present invention.

FIG. 3 is a schematic diagram of a multi-cell structure according to the present invention.

Detailed Description

The present invention will be further described with reference to the drawings attached to the specification, but the present invention is not limited to the following examples.

In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "left", "right", "upper", "lower", "middle", "bottom", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention.

In the description of the invention, it is to be noted that, unless otherwise specifically defined and limited, the names of the specialized parts are those normally understood by those skilled in the art, such as the bubble cap plate 26, also called bubble cap plate, which is the earliest type of plate used in industry, and the gas-liquid contact element of the bubble cap plate is a bubble cap, which has two main types of circular and strip, and the liquid layer escapes from the slit formed in the lower portion of the bubble cap through the revolving path between the bubble cap and the gas lift tube.

A multi-strand wound tube heat exchanger with tube passes capable of being cleaned on line is provided, and the multi-strand wound tube heat exchanger with the tube passes capable of being cleaned on line can be formed by connecting two or more heat exchange units 29 in series, wherein each heat exchange unit 29 is identical in structure, the main structure of the heat exchanger is equivalent to that of a plurality of wound tube heat exchangers in series, as shown in fig. 3, the multi-strand wound tube heat exchanger is a specific embodiment and is formed by connecting three heat exchange units 29 in series, each heat exchange unit 29 is identical in structure, an upper tube box of the heat exchanger is communicated with a columnar tube box through an upper heat exchange unit spiral tube bundle and communicated with a lower tube box of the heat exchanger through a lower heat exchange unit spiral tube bundle to jointly form a tube pass of the heat exchanger, a space outside the upper heat exchange unit tube body area spiral tube bundle forms a shell pass I, and a;

as shown in fig. 1-2, a specific embodiment of a multi-strand wound tube heat exchanger with online cleanable tube passes is provided, wherein two heat exchange units are used, a columnar tube box 7 is used for connecting two adjacent heat exchange units, a distributor 12, a porous plate 9 and a bubble cap plate (bubble cap plate) 26 are arranged in the tube box, the embodiment specifically comprises a tube body, an upper tube plate and a lower tube plate are connected in the tube body, the upper tube plate and the lower tube plate divide the interior of the tube body into an upper tube box 1, a middle tube body 2 and a lower tube box 3, a first tube plate 4 and a second tube plate 5 are connected in the middle tube body 2, the first tube plate 4 and the second tube plate 5 divide the inner cavity of the middle tube body 2 into an upper tube body 6, a columnar tube box 7 and a lower tube body 8 from top to bottom, the porous plate 9 is connected in the tube box 7, the porous plate 9 divides the tube box 7 into an, an annular tubular distributor 12 is arranged in the upper space 10, a plurality of nozzles 13 are connected to the distributor 12, a demineralized water inlet pipe 27 is connected to the outer wall of the middle cylinder 2, the demineralized water inlet pipe 27 extends into the upper space 10 and is communicated with the distributor 12, and a bubble cap plate 26 is connected in the lower space 11;

the upper barrel 6 and the lower barrel 8 are both internally provided with a pipeline 16, the upper tube box 1 is communicated with an upper space 10 through the pipeline 16 in the upper barrel 6, the lower tube box 3 is communicated with a lower space 11 through the pipeline 16 in the lower barrel 8, a first cold medium outlet 17 and a first cold medium inlet 18 are respectively communicated with the side wall of the upper end of the upper barrel 6 and the side wall of the lower end of the upper barrel 6, a second cold medium outlet 19 and a second cold medium inlet 20 are respectively communicated with the side wall of the upper end of the lower barrel 8 and the side wall of the lower end of the lower barrel 8, a heat medium inlet 21 is communicated with the upper end of the upper tube box 1, and a heat medium outlet 22 is communicated with the lower end of the;

high-temperature materials sequentially enter the pipelines 16 of the upper tube box 1 and the upper barrel 6 from a tube pass heat medium inlet 21, namely enter the tube pass of the upper heat exchange unit, then enter the tube box 7 which is columnar and shared by the two heat exchange units, then sequentially enter the pipelines 16 in the lower barrel 8 and the lower tube box 3, namely enter the tube pass of the lower heat exchange unit, and finally flow out from a tube pass bottom heat medium outlet 22, each heat exchange unit is provided with a group of cold material inlets and outlets, a first low-temperature material participating in heat exchange enters through a first cold medium inlet 18 at the bottom of the shell pass of the upper heat exchange unit (the shell pass of the upper barrel 6) and flows out from a first cold medium outlet 17 at the upper part of the shell pass of the upper heat exchange unit, a second low-temperature material participating in heat exchange enters through a second cold medium inlet 20 at the shell pass of the lower heat exchange unit (the shell pass of the lower barrel 8), flows out from a second cold medium outlet 19 at, more preferably, the deoxidized water is generally required to have an oxygen content of not more than 20 mug/g and a chloride ion content of not more than 5 mug/g, the nozzle 13 of the distributor 13 uniformly distributes the injected desalted water on the cross section of the pipe box 7, the porous plate 9 is used for primarily distributing and mixing the pipe pass material and the desalted water, the bubble cap plate 26 (also called bubble cap plate, which is the earliest column plate in industrial application, the gas-liquid contact element of the bubble cap plate is bubble cap, and has two types of circular and strip, and the gas-liquid contact element is bubble cap, and escapes from a tooth seam formed at the lower part of the bubble cap through a rotary passage between the bubble cap and a gas lifting pipe) is used for redistributing and mixing the oil phase, the gas-liquid phase substance and the desalted water in the pipe pass material to prevent the gas-liquid phase drift, the desalted water injected into the pipe pass dissolves ammonium salt crystals generated at the low temperature section of the pipe pass and then is discharged along, the invention can be applied to a hydrogenation device for processing high-nitrogen high-chlorine raw oil, can break through the bottleneck of temperature limitation after heat exchange of reaction products in the heat exchange network design, avoids heat exchange efficiency reduction, system pressure drop increase, device energy consumption increase and even forced shutdown caused by ammonium salt crystallization, keeps the device to stably operate for a long time, can simultaneously exchange heat with more than two cold materials, and saves equipment installation space and equipment investment.

As an improvement, the demineralized water inlet pipe 27 is connected with a water supply pipe through a flange, the water supply pipe is connected with a valve, a flowmeter and a pressure gauge, the valve comprises a regulating valve, a hand valve and a one-way valve, the space except the pipeline 16 in the upper cylinder 6 and the lower cylinder 8 forms a heat exchanger shell pass, the flowmeter on the demineralized water supply pipe is used for monitoring the amount of the injected demineralized water, the valve or the regulating valve on the demineralized water supply pipe is used for accurately controlling the flow of the injected demineralized water so as to ensure the optimal cleaning effect, the one-way valve on the demineralized water supply pipe is used for preventing medium from flowing backwards in the pipe pass after the accidental interruption of the demineralized water, and the pressure gauge on the demineralized water supply pipe is used for monitoring the pressure difference variation trend of each heat exchange.

As an improvement, a first central tube 14 and a second central tube 15 are respectively arranged in the upper barrel 6 and the lower barrel 8, two ends of the first central tube 14 are respectively connected to the upper tube plate and the first tube plate 4, two ends of the second central tube 15 are respectively connected to the lower tube plate and the second tube plate 5, and through holes are formed in the upper tube plate, the lower tube plate, the first tube plate 4 and the second tube plate 5; the upper end of a pipeline 16 in the upper cylinder 6 is inserted into the through hole of the upper tube plate to be communicated with the upper tube box 1, the lower end of the pipeline 16 extends downwards and forms a spiral shape around the first central tube 14, and the lower end of the pipeline 16 is inserted into the through hole of the first tube plate 4 to be communicated with the upper space 10; the upper end of a pipeline 16 in the lower cylinder 8 is inserted into the through hole of the second tube plate 5 to be communicated with the lower space 11, the lower end of the pipeline 16 extends downwards and forms a spiral shape around the second central tube 15, and the lower end of the pipeline 16 is inserted into the through hole of the lower tube plate to be communicated with the lower tube box 3; the upper tube box 1 and the upper space 10 and the lower tube box 3 and the lower space 11 are connected through a pipeline 16 to form a heat exchanger tube pass; the design of the helical tube 20 allows the tube 16 to be exposed to a large area in the shell side of the heat exchanger, which facilitates the realization of sufficient heat exchange.

As an improvement, a plurality of through holes with the same number are respectively formed in the upper tube plate, the lower tube plate, the first tube plate 4 and the second tube plate 5, the through holes of the upper tube plate are surrounded into a circular structure, the through holes of the first tube plate 4 are in one-to-one correspondence with the through holes of the upper tube plate from top to bottom, a pipeline 16 is inserted into each through hole of the upper tube plate, and the pipelines 16 surround the first central tube 14 in sequence and in the same direction to form a layer of spiral tube bundle to cover the first central tube 14; the through holes of the second tube plate 5 are surrounded into a pattern structure, the through holes of the lower tube plate are in up-down one-to-one correspondence with the through holes of the second tube plate 5, a pipeline 16 is inserted into each through hole of the second tube plate 5, and the pipelines 16 surround the second central tube 15 in sequence and in the same direction to form a layer of spiral tube bundle to cover the second central tube 15; the design of the multi-layer helical tube 20 provides a large area of the tube 16 exposed in the shell side of the heat exchanger, which facilitates the achievement of sufficient heat exchange.

As an improvement, through holes in the upper tube plate and the second tube plate 5 are encircled to form three circles which are concentrically arranged, pipelines 16 in the same round upper through hole on the upper tube plate surround the first central tube 14 in sequence and in the same direction to form a layer of spiral tube bundle, a first cushion block 23 is arranged between adjacent layers of spiral tube bundles for spacing, a second cushion block 24 is arranged between the innermost layer of spiral tube bundle and the first central tube 14, and the spiral directions of the two adjacent layers of spiral tube bundles are opposite;

the pipelines 16 in the same circular upper through hole on the second tube plate 5 surround the second central tube 15 in sequence and in the same direction to form a layer of spiral tube bundle, a first cushion block 23 is arranged between adjacent layers of spiral tube bundles at intervals, a second cushion block 24 is arranged between the innermost layer of spiral tube bundle and the second central tube 15, and the spiral directions of the adjacent layers of spiral tube bundles are opposite;

the design of adding cushion 23, No. two cushion 24 for also can circulate hot medium between the spiral tube bundle of adjacent layer, the efficient heat transfer of being convenient for, in limited upper barrel 6, lower barrel 8, design multilayer spiral tube bank, both can make heat exchange efficiency high, also can satisfy the settlement circulation between upper tube case 1, lower tube case 3.

As an improvement, the first central tube 14 and the middle cylinder body 2 and the second central tube 15 and the middle cylinder body 2 are coaxial, and have symmetrical structures, so that heat exchange is facilitated.

As an improvement, the side walls of the lower ends of the upper cylinder 6 and the lower cylinder 8 are also communicated with a shell pass liquid outlet 25 to prevent moisture from gathering at the lower part of the shell pass of the heat exchanger to generate wet hydrogen sulfide corrosion.

As an improvement, the first cold medium outlet 17 and the first cold medium inlet 18 are respectively located on the left and right side surfaces of the upper cylinder 6, and the second cold medium outlet 19 and the second cold medium inlet 20 are respectively located on the left and right side surfaces of the lower cylinder 8, so that circulation and heat exchange of cold and hot media are facilitated.

As an improvement, distributor 12 is equipped with a plurality of, and a plurality of distributor 12 volume reduces gradually, the order cover is established in proper order between distributor 12 and is formed with the concentric circle of multilayer, and intercommunication between adjacent distributor 12, salt solution inlet tube 27 stretches into in the upper space 10 and outermost distributor 12 intercommunication, and the connection is the tandem mode between distributor 13, and concrete distributor 12 quantity can be selected according to column pipe case 7 space size, demineralized water input volume etc. and the restriction of quantity change is not done to this application.

As a refinement, there are 2 distributors 12.

Finally, it should be noted that the present invention is not limited to the above embodiments, and many variations are possible. All modifications which can be derived or suggested by a person skilled in the art from the disclosure of the present invention are to be considered within the scope of the invention.

Claims

1. The utility model provides a tube side can online cleaning's stranded stream winding pipe heat exchanger which characterized in that: the barrel comprises a barrel body, an upper tube plate and a lower tube plate are connected in the barrel body, the barrel body is internally divided into an upper tube box (1), a middle barrel body (2) and a lower tube box (3) by the upper tube plate and the lower tube plate, a first tube plate (4) and a second tube plate (5) are connected in the middle barrel body (2), the first tube plate (4) and the second tube plate (5) divide an inner cavity of the middle barrel body (2) into the upper barrel body (6), a columnar tube box (7) and the lower barrel body (8) from top to bottom, a porous plate (9) is connected in the tube box (7), the tube box (7) is divided into an upper space (10) and a lower space (11) by the porous plate (9), an annular tubular distributor (12) is arranged in the upper space (10), a plurality of nozzles (13) are connected on the distributor (12), a demineralized water inlet pipe (27, a desalted water inlet pipe (27) extends into the upper space (10) and is communicated with the distributor (12), and a bubble cap plate (26) is connected in the lower space (11);

the cooling device is characterized in that pipelines (16) are arranged in the upper barrel (6) and the lower barrel (8), the upper tube box (1) is communicated with the upper space (10) through the pipelines (16) in the upper barrel (6), the lower tube box (3) is communicated with the lower space (11) through the pipelines (16) in the lower barrel (8), a first cold medium outlet (17) and a first cold medium inlet (18) are respectively communicated with the side wall of the upper end of the upper barrel (6) and the side wall of the lower end of the upper barrel (6), a second cold medium outlet (19) and a second cold medium inlet (20) are respectively communicated with the side wall of the upper end of the lower barrel (8) and the side wall of the lower end of the lower barrel (8), a hot medium inlet (21) is communicated with the upper end of the upper tube box (1), and a hot medium outlet (22) is.

2. The multi-strand wound tube heat exchanger with the tube pass capable of being cleaned on line as claimed in claim 1, wherein: the demineralized water inlet pipe (27) is connected with a water supply pipeline through a flange, the water supply pipeline is connected with a valve, a flowmeter and a pressure gauge, the valve comprises an adjusting valve, a hand valve and a one-way valve, and the space except for the pipeline (16) in the upper cylinder body (6) and the lower cylinder body (8) forms a shell pass of the heat exchanger.

3. The multi-strand wound tube heat exchanger with the tube pass capable of being cleaned on line as claimed in claim 1 or 2, wherein: a first central tube (14) and a second central tube (15) are respectively arranged in the upper cylinder (6) and the lower cylinder (8), two ends of the first central tube (14) are respectively connected to the upper tube plate and the first tube plate (4), two ends of the second central tube (15) are respectively connected to the lower tube plate and the second tube plate (5), and through holes are formed in the upper tube plate, the lower tube plate, the first tube plate (4) and the second tube plate (5);

the upper end of a pipeline (16) in the upper cylinder (6) is inserted into a through hole of the upper tube plate to be communicated with the upper tube box (1), the lower end of the pipeline (16) extends downwards and surrounds a first central tube (14) to form a spiral shape, and the lower end of the pipeline (16) is inserted into the through hole of the first tube plate (4) to be communicated with the upper space (10);

the upper end of an inner pipeline (16) of the lower cylinder (8) is inserted into a through hole of the second tube plate (5) to be communicated with the lower space (11), the lower end of the pipeline (16) extends downwards and surrounds the second central tube (15) to form a spiral shape, and the lower end of the pipeline (16) is inserted into the through hole of the lower tube plate to be communicated with the lower tube box (3);

the upper pipe box (1) is connected with the upper space (10) and the lower pipe box (3) is connected with the lower space (11) through a pipeline (16) to form a heat exchanger tube pass.

4. The multi-strand wound tube heat exchanger with the tube pass capable of being cleaned on line as claimed in claim 3, wherein: the upper tube plate, the lower tube plate, the first tube plate (4) and the second tube plate (5) are respectively provided with a plurality of through holes with the same number, the through holes of the upper tube plate are surrounded into a circular structure, the through holes of the first tube plate (4) are in one-to-one correspondence with the through holes of the upper tube plate from top to bottom, a pipeline (16) is inserted into the through holes of the upper tube plate, and the pipeline (16) surrounds the first central tube (14) in sequence and in the same direction to form a layer of spiral tube bundle to cover the first central tube (14);

the through holes of the second tube plate (5) are surrounded into a pattern structure, the through holes of the lower tube plate are in up-down one-to-one correspondence with the through holes of the second tube plate (5), a pipeline (16) is inserted into each through hole of the second tube plate (5), and the pipeline (16) surrounds the second central tube (15) in sequence and in the same direction to form a layer of spiral tube bundle to cover the second central tube (15).

5. The multi-strand wound tube heat exchanger with the tube pass capable of being cleaned on line as claimed in claim 4, wherein: the through holes in the upper tube plate and the second tube plate (5) are encircled into three concentrically arranged circles, pipelines (16) in the same circular upper through hole on the upper tube plate surround the first central tube (14) in sequence and in the same direction to form a layer of spiral tube bundle, first cushion blocks (23) are arranged between adjacent layers of spiral tube bundles at intervals, second cushion blocks (24) are arranged between the innermost layer of spiral tube bundle and the first central tube (14), and the spiral directions of the adjacent layers of spiral tube bundles are opposite;

a pipeline (16) in the through hole on the second pipe plate (5) and the same circle surrounds a second central pipe (15) in sequence and in the same direction to form a layer of spiral pipe bundle, a first cushion block (23) is arranged between adjacent layers of spiral pipe bundles at intervals, a second cushion block (24) is arranged between the innermost layer of spiral pipe bundle and the second central pipe (15), and the spiral directions of the two adjacent layers of spiral pipe bundles are opposite.

6. The multi-strand wound tube heat exchanger with the tube pass capable of being cleaned on line as claimed in claim 3, wherein: the first central tube (14) and the middle cylinder body (2) and the second central tube (15) and the middle cylinder body (2) are coaxial.

7. The multi-strand wound tube heat exchanger with the tube pass capable of being cleaned on line as claimed in claim 2, wherein: the side walls of the lower ends of the upper cylinder (6) and the lower cylinder (8) are also communicated with a shell pass liquid discharge port (25) to prevent moisture from gathering at the lower part of the shell pass of the heat exchanger to generate wet hydrogen sulfide corrosion.

8. The multi-strand wound tube heat exchanger with the tube pass capable of being cleaned on line as claimed in claim 2, wherein: the first cold medium outlet (17) and the first cold medium inlet (18) are respectively positioned on the left side surface and the right side surface of the upper cylinder body (6), and the second cold medium outlet (19) and the second cold medium inlet (20) are respectively positioned on the left side surface and the right side surface of the lower cylinder body (8).

9. The multi-strand wound tube heat exchanger with the tube pass capable of being cleaned on line as claimed in claim 1, wherein: the water distributor is characterized in that the number of the distributors (12) is multiple, the volume of the plurality of distributors (12) is gradually reduced, the distributors (12) are sequentially sleeved with multiple layers of concentric circles, adjacent distributors (12) are communicated through communicating pipes, the number of the communicating pipes between adjacent distributors (13) is more than or equal to 1, and the brine inlet pipe (27) extends into the upper space (10) and is communicated with the outermost distributor (12).

10. The multi-strand wound tube heat exchanger with the tube pass capable of being cleaned on line as claimed in claim 9, wherein: the number of the distributors (12) is 2.