CN216169997U

CN216169997U - Alkali evaporation device

Info

Publication number: CN216169997U
Application number: CN202122078008.8U
Authority: CN
Inventors: 王永建; 魏金堂; 刘志军; 程早阳
Original assignee: Tianjin Bohua Engineering Co ltd
Current assignee: Tianjin Bohua Engineering Co ltd
Priority date: 2021-08-31
Filing date: 2021-08-31
Publication date: 2022-04-05
Anticipated expiration: 2031-08-31

Abstract

The utility model discloses an alkali evaporation device, wherein a liquid inlet is arranged at the outer top of an upper pipe box, the upper surface of a butterfly-shaped end enclosure is used for distributing liquid, a distribution disc is arranged right below the butterfly-shaped end enclosure, one or more than one down-flow pipes communicated with the distribution disc are fixed on the bottom surface of the distribution disc, a pipe plate is fixed below the down-flow pipes, and the upper pipe box and a heat exchanger are spaced by the pipe plate; be equipped with a plurality of heat exchange tubes that supply liquid to flow through in the heat exchanger, the heat exchange tube extends along the length direction of heat exchanger, the top of heat exchange tube is fixed in on the tube sheet, and the top of heat exchange tube is equipped with cloth membrane head, in liquid on the tube sheet enters into the heat exchange tube via cloth membrane head, the heat exchanger passes through tube sheet interval down with the gas-liquid separation jar, the bottom of heat exchange tube is passed down the tube sheet and is linked together with the gas-liquid separation jar, the top of gas-liquid separation jar is equipped with steam outlet, steam outlet's below is equipped with the defroster, the bottom of gas-liquid separation jar is equipped with liquid outlet. The utility model can effectively reduce the energy consumption of alkali evaporation.

Description

Alkali evaporation device

Technical Field

The utility model relates to the technical field of chemical engineering, in particular to an alkali evaporation device.

Background

The alkali evaporation process is roughly divided into the following steps: 32 percent of raw material alkali from the ionic membrane electrolysis procedure is sent into an alkali liquor storage tank, added into a triple-effect evaporator from the top through an alkali liquor pump, and flows downwards along the inner wall of a tube array of the triple-effect evaporator under the operating pressure of 13.5kPa to exchange heat with secondary steam of the double-effect evaporator. After concentration, alkali liquor with the concentration of 36.5% is sent to an alkali liquor preheater through a conveying pump part to exchange heat with 50% alkali liquor of a first-effect evaporator, part of the alkali liquor is sent to an alkali liquor heat exchanger b to exchange heat with steam condensate of the first-effect evaporator, the two parts are converged and then sent to the top of a second-effect evaporator, secondary steam generated by the third-effect evaporator is condensed by a surface condenser, and non-condensable gas in the secondary steam is pumped out by a water ring vacuum pump.

The second-effect evaporator is operated under the operation pressure of 0.049MPa, 36.5 percent of alkali liquor is heated by secondary steam of the first-effect evaporator, and is further concentrated into 41.8 percent of alkali liquor which then enters a gas-liquid separator. The liquid is sent to an alkali liquid preheater through the conveying pump part to exchange heat with 50% alkali liquid of the first-effect evaporator, part of the liquid is sent to an alkali liquid heat exchanger b to exchange heat with steam condensate of the first-effect evaporator, the two parts are converged and then sent to the top of the first-effect evaporator, and secondary steam generated by the second-effect evaporator is sent to the third-effect evaporator to serve as a heating heat source of the third-effect evaporator.

The first effect evaporator is operated under the operation pressure of 0.21MPa, 42 percent of alkali liquor is heated by the raw steam in the shell pass, and the alkali liquor is further concentrated into 50 percent of alkali liquor and then enters a vapor-liquid separator. Pumping the mixture into an alkali liquor preheater and an alkali liquor heat exchanger b by a 50% alkali pump, cooling the mixture to below 45 ℃ by a cooler, and feeding the cooled mixture into a storage tank.

The existing evaporator of the alkali evaporation process has different feeding forms, different distributor forms, larger difference of falling film forming effect, unsatisfactory distributor form design, uneven film forming and influence on evaporation effect.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide an alkali evaporation device aiming at the technical defects in the prior art.

The technical scheme adopted for realizing the purpose of the utility model is as follows:

the utility model provides an alkali evaporation plant, includes by lower to last gas-liquid separation jar, heat exchanger and the upper portion case of sealing connection in proper order, wherein:

a liquid inlet is formed in the outer top of the upper pipe box, an inlet baffle pipe communicated with the liquid inlet is arranged in the upper pipe box, a butterfly-shaped end socket is arranged right below the inlet baffle pipe, the upper surface of the butterfly-shaped end socket is used for distributing liquid, a distribution disc is arranged right below the butterfly-shaped end socket, one or more than one down-flow pipes communicated with the distribution disc are fixed on the bottom surface of the distribution disc, a pipe plate is fixed below the down-flow pipes, and the upper pipe box and the heat exchanger are spaced through the pipe plate;

the heat exchanger is internally provided with heat exchange tubes for liquid to flow through, the number of the heat exchange tubes is set according to the heat exchange area of the process requirement, the heat exchange tubes extend along the length direction of the heat exchanger, the top of each heat exchange tube is fixed on the tube plate, the top of each heat exchange tube is provided with a film distribution head, liquid on the tube plate enters the heat exchange tubes through the film distribution heads, the side walls of the heat exchanger are provided with steam inlets, and steam entering from the steam inlets exchanges heat with the liquid in the heat exchange tubes through the heat exchange tubes;

the heat exchanger and the gas-liquid separation tank are separated through a lower tube plate, the bottom of the heat exchange tube penetrates through the lower tube plate and is communicated with the gas-liquid separation tank, a steam outlet is formed in the top of the gas-liquid separation tank, a demister is arranged below the steam outlet, and a liquid outlet is formed in the bottom of the gas-liquid separation tank.

In the above technical scheme, the outer wall of the heat exchanger is composed of an inner lining cylinder and an expansion outer sleeve hermetically connected to the outer side of the inner lining cylinder, the steam inlet is arranged on the expansion outer sleeve, the heat exchange tube is located in the inner lining cylinder, a gap for steam to enter is formed on the inner lining cylinder, and the gap is located in the expansion outer sleeve and is staggered with the steam inlet. The steam adopts an expansion joint built-in lining barrel structure, so that the steam is prevented from directly blowing to the heat exchange tube, and the steam is more uniform after entering.

In the above technical scheme, the heat exchange tubes are arranged in the heat exchanger in a triangular shape, specifically in a regular triangular shape or an oblique triangular shape.

In the technical scheme, baffle plates which are arranged in a left-right staggered mode are fixed on the side wall in the heat exchanger, the baffle plates are fixed through distance pipes which are vertically arranged, pull rods are sleeved in the distance pipes, threads are arranged at two ends of each pull rod, and the pull rods are fixed on the baffle plates through nuts matched with the pull rods. The baffle plate provides a baffling effect on the fluid in the heat exchanger, and prevents the fluid in the shell from flowing straight.

In the technical scheme, the lengths of the heat exchange tubes are the same, and the lengths of the heat exchange tubes are kept to be uniform.

In the above technical scheme, cloth membrane head is both ends open-ended drum structure, the one end of cloth membrane head is the throat end to the matching inserts in the heat-exchange tube, be equipped with the vertical fluting that supplies liquid inflow of one or more annular equipartitions on the lateral wall of cloth membrane head, grooved one end begin with another tip that the throat end is relative, the other end is located the middle part of cloth membrane head does not reach the tip of the throat end of cloth membrane head.

In the above technical scheme, the fluting divide into along the length direction of cloth membrane head to be close to the first fluting section and the principle of throat end the second fluting section of throat end, first fluting section is oblique fluting, contained angle from the top down between two slope lateral walls of oblique fluting is 30 by the 60 gradual change, it is parallel between two lateral walls of second fluting section, first fluting section and second fluting section are located the opening width of cloth membrane head inner wall one side the same, first fluting section is located the opening of cloth membrane head outer wall one side diminishes by the width from the top down, until diminish to with the second fluting section is located the opening width of cloth membrane head outer wall one side is the same, the second fluting section is located the opening of cloth membrane head outer wall one side keeps unanimous by from the top down. The first grooving section is horn-like, and the liquid feeding is more, can further improve the homogeneity of liquid film distribution.

In the technical scheme, the steam inlet is arranged in the middle of the shell of the heat exchanger, the top of the shell of the heat exchanger is provided with the exhaust port, and the bottom of the shell is provided with the condensed water outlet.

In the technical scheme, a pressure gauge connecting port is arranged at the top of a shell of the heat exchanger, a drain port is arranged at the bottommost part of the shell of the heat exchanger, an evaporator connector at the bottom of the heat exchanger is connected with a heat exchanger connecting port at the top of the gas-liquid separation tank in a sealing mode, a gasket and a gasket are arranged between the evaporator connector and the heat exchanger connecting port, and the gasket and the heat exchanger are fastened and sealed through nuts and studs.

In the technical scheme, a plurality of liquid level meter ports are arranged on the side wall of the gas-liquid separation tank, one of the liquid level meter ports is located at the bottom of the gas-liquid separation tank, the other two liquid level meter ports are located at the middle upper part of the gas-liquid separation tank, a manhole is arranged on the side wall of the gas-liquid separation tank, the demister is a wire mesh demister, the demister is obliquely arranged below the steam outlet, a liquid inlet is arranged on the side wall of the gas-liquid separation tank, and the liquid inlet is located below the demister.

Compared with the prior art, the utility model has the beneficial effects that:

1. the alkali evaporation device disclosed by the utility model is high in liquid distribution uniformity through multi-step liquid distribution, and particularly, the side wall of the film distribution head is obliquely provided with the groove, so that liquid rotates on the inner wall of the heat exchange tube to form a uniform film, the heat exchange efficiency is further improved, and the energy consumption of the alkali evaporation device is reduced.

2. The steam outlet of the gas-liquid separation tank in the device is positioned at the top of the gas-liquid separation tank, so that the alkali liquor stock can be effectively increased, and the demisting effect can be improved.

Drawings

FIG. 1 is a schematic view showing the structure of an alkali evaporation apparatus.

Fig. 2 is a schematic view of the upper header and its connection to the heat exchanger.

Fig. 3 is a schematic structural view of a heat exchange tube.

Fig. 4 is a schematic structural view of a film laying head of embodiment 3, wherein (a) is a side view and (b) is a top view.

Fig. 5 is an assembly schematic of the film laying head.

In the figure: a-gas-liquid separation tank, b-heat exchanger, c-upper tube box

1-a liquid inlet, 2-an inlet baffle pipe, 3-a butterfly-shaped end socket, 4-a distribution plate, 5-a down-flow pipe, 6-a pipe plate, 7-a heat exchange pipe, 8-a film distribution head, 9-a steam inlet, 10-a steam outlet, 11-a demister, 12-a liquid outlet, 13-a lower pipe plate, 14-an inner lining, 15-an expansion outer sleeve, 16-a gap, 17-a baffle plate, 18-a distance pipe, 19-a necking end, 20-a slot, 21-an exhaust port, 22-a condensate outlet, 23-a pressure gauge connecting port, 24-a purging port, 25-an evaporator interface, 26-a heat exchanger connecting port, 27-a liquid level meter port, 28-a manhole and 29-a liquid inlet.

20-1-a first grooving section and 20-2-a second grooving section.

Detailed Description

The utility model is described in further detail below with reference to the figures and specific examples. It should be understood that the specific embodiments described herein are merely illustrative of the utility model and are not intended to limit the utility model.

Example 1

An alkali evaporation device comprises a gas-liquid separation tank a, a heat exchanger b and an upper pipe box c which are sequentially and hermetically connected from bottom to top, wherein:

a liquid inlet 1 is arranged at the outer top of the upper pipe box c, an inlet baffle pipe 2 communicated with the liquid inlet 1 is arranged in the upper pipe box c, a butterfly-shaped end socket 3 is arranged right below the inlet baffle pipe 2, the upper surface of the butterfly-shaped end socket 3 is used for distributing liquid, a distribution disc 4 is arranged right below the butterfly-shaped end socket 3, one or more downcomers 5 communicated with the distribution disc 4 are fixed on the bottom surface of the distribution disc 4, a pipe plate 6 is fixed below the downcomers 5, and the upper pipe box c and the heat exchanger b are separated by the pipe plate 6;

a plurality of heat exchange tubes 7 for liquid to flow through are arranged in the heat exchanger b, the number of the heat exchange tubes 7 is set according to the heat exchange area of the process requirement, the heat exchange tubes 7 extend along the length direction of the heat exchanger b, the top of each heat exchange tube 7 is fixed on the tube plate 6, a film distribution head 8 is assembled at the top of each heat exchange tube 7, liquid on the tube plate 6 enters the heat exchange tubes 7 through the film distribution heads 8, a steam inlet 9 is arranged on the side wall of the heat exchanger b, and steam entering from the steam inlet 9 exchanges heat with the liquid in the heat exchange tubes 7 through the heat exchange tubes 7;

the heat exchanger b and the gas-liquid separation tank a are separated by a lower tube plate 13, the bottom of the heat exchange tube 7 penetrates through the lower tube plate 13 and is communicated with the gas-liquid separation tank a, a steam outlet 10 is formed in the top of the gas-liquid separation tank a, a demister 11 is arranged below the steam outlet 10, and a liquid outlet 12 is formed in the bottom of the gas-liquid separation tank a.

In the device, an inlet baffle pipe 2 is additionally arranged, and the alkali liquor is collected and distributed at a liquid inlet 1 by the inlet baffle pipe 2. NaOH collected by the inlet baffle pipe 2 falls on the butterfly-shaped end enclosure 3 and falls into the distribution disc 4 after being redistributed on the upper surface of the butterfly-shaped end enclosure 3. The number and distribution of the downcomers 5 are determined by calculation, so that the alkali liquor uniformly falls on the tube plate 6 through the downcomers 5.

On the tube plate 6, alkali liquor uniformly enters the heat exchange tube 7 after passing through the membrane distributing head 8, a film is formed on the inner wall of the heat exchange tube 7, the film is evaporated through heat exchange of the heat exchange tube 7, steam with the alkali liquor generated by the heat exchanger b enters the gas-liquid separation tank a for separation, and the steam with the alkali liquor entering the gas-liquid separation tank a is discharged from the steam outlet 10 of the upper end enclosure after passing through the demister 11, so that the alkali liquor storage can be increased, and the demisting effect can be increased.

Example 2

Preferably, the outer wall of the heat exchanger b is composed of an inner lining 14 and an expansion outer sleeve 15 hermetically connected to the outside of the inner lining 14, the steam inlet 9 is arranged on the expansion outer sleeve 15, the heat exchange tubes 7 are positioned in the inner lining 14, gaps 16 for steam to enter are formed on the inner lining 14, and the gaps 16 are positioned in the expansion outer sleeve 15 and are staggered with the steam inlet 9. The steam adopts an expansion joint built-in lining barrel structure, so that the steam is prevented from directly blowing to the heat exchange tube 7, and the steam is more uniform after entering.

Preferably, the heat exchange tubes 7 are arranged in the heat exchanger b in a regular triangle shape, so that the heat exchange effect can be optimized. As shown, each intersection represents the presence of one heat exchange tube 7.

Preferably, baffle plates 17 which are arranged in a left-right staggered mode are fixed on the side wall in the heat exchanger b, the baffle plates 17 are fixed through distance pipes 18 which are vertically arranged, pull rods are sleeved in the distance pipes 18, threads are arranged at two ends of each pull rod, and the pull rods are fixed on the baffle plates 17 through nuts matched with the pull rods. The baffle 17 provides a baffle effect to the fluid located in the heat exchanger b, avoiding a straight flow of fluid inside the casing.

Preferably, the lengths of the heat exchange tubes 7 are the same, and the lengths of the heat exchange tubes 7 are kept uniform. This avoids the situation where some of the heat exchanger b feeds from the side of the header resulting in uneven feeding.

Example 3

As shown in fig. 4, the film distribution head 8 is a cylinder structure with two open ends, one end of the film distribution head 8 is a necking end 19 (the necking end 19 is the lower end of the film distribution head 8, the other end is the upper end) to be inserted into the heat exchange tube 7 in a matching manner, one or more vertical slots 20 which are annularly and uniformly distributed and are used for liquid to flow in are arranged on the side wall of the film distribution head 8, one end of each slot 20 is started from the other end opposite to the necking end 19, the other end of each slot is positioned in the middle of the film distribution head 8, and the end of the necking end 19 of the film distribution head 8 is not reached.

The slot 20 is divided into a first slot section 20-1 close to the necking end 19 and a second slot section 20-2 of the necking end 19 in principle along the length direction of the film distribution head, the first grooving section 20-1 is an inclined grooving, the included angle between two inclined side walls of the inclined grooving is gradually changed from 60 degrees to 30 degrees from top to bottom, the two side walls of the second slotting section 20-2 are parallel, the opening widths of the first slotting section 20-1 and the second slotting section 20-2 at one side of the inner wall of the film distributing head 8 are the same, the width of the opening of the first groove opening section 20-1 at one side of the outer wall of the film distribution head 8 is reduced from top to bottom until the width is the same as the width of the opening of the second groove opening section 20-2 at one side of the outer wall of the film distribution head 8, the opening of the second grooved section 20-2 on the outer wall side of the film laying head 8 is consistent from top to bottom.

The first groove section 20-1 is horn-like, the liquid feeding amount is large, and the uniformity of liquid film distribution can be further improved.

Example 4

Preferably, the liquid inlet 1, the inlet baffle pipe 2, the butterfly-shaped end enclosure 3, the distribution plate 4 and the shell of the upper channel c are coaxially arranged. The uniformity of alkali liquor distribution is increased.

Preferably, the steam inlet 9 is arranged in the middle of the shell of the heat exchanger b, the top of the shell of the heat exchanger b is provided with an exhaust port 21, the bottom of the shell is provided with a condensed water outlet 22, condensed water generated after the steam is subjected to heat exchange is discharged from the condensed water outlet 22, and uncooled gas is discharged through the exhaust port 21.

Furthermore, a pressure gauge connecting port 23 is arranged at the top of the shell of the heat exchanger b. The pressure gauge connecting port 23 is used for assembling a pressure gauge.

Furthermore, the lowest part of the shell of the heat exchanger b is provided with a drain port 24 to drain the liquid in the heat exchanger b.

Preferably, an evaporator connector 25 at the bottom of the heat exchanger b is hermetically connected with a heat exchanger connector 26 at the top of the gas-liquid separation tank a, and a gasket are arranged between the evaporator connector 25 and the heat exchanger connector 26 and are fastened and sealed by a nut and a stud.

Preferably, a plurality of level meter ports 27 are provided on the sidewall of the gas-liquid separation tank a, wherein one of the level meter ports 27 is located at the bottom of the gas-liquid separation tank a, and the other two level meter ports 27 are located at the middle upper part of the gas-liquid separation tank a.

Preferably, a manhole 28 is provided on a sidewall of the gas-liquid separation tank a, and is used for operations such as maintenance.

Preferably, the demister 11 is a wire mesh demister and is disposed obliquely below the steam outlet 10. The separation effect is optimized. And a liquid inlet 29 is arranged on the side wall of the gas-liquid separation tank a, and the liquid inlet 29 is positioned below the demister 11 and is used for flushing the wire mesh demister.

Spatially relative terms, such as "upper," "lower," "left," "right," and the like, may be used in the embodiments for ease of description to describe one element or feature's relationship to another element or feature as illustrated in the figures. It will be understood that the spatial terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" other elements or features would then be oriented "above" the other elements or features. Thus, the exemplary term "lower" can encompass both an upper and a lower orientation. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

Moreover, relational terms such as "first" and "second," and the like, may be used solely to distinguish one element from another element having the same name, without necessarily requiring or implying any actual such relationship or order between such elements.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims

1. The utility model provides an alkali evaporation plant, its characterized in that includes by lower to last sealing connection's gas-liquid separation jar, heat exchanger and upper portion pipe case in proper order, wherein:

a heat exchange tube for liquid to flow through is arranged in the heat exchanger, the heat exchange tube extends along the length direction of the heat exchanger, the top of the heat exchange tube is fixed on the tube plate, a film distribution head is assembled at the top of the heat exchange tube, liquid on the tube plate enters the heat exchange tube through the film distribution head, a steam inlet is arranged on the side wall of the heat exchanger, and steam entering from the steam inlet exchanges heat with the liquid in the heat exchange tube through the heat exchange tube;

2. The alkali evaporating device as claimed in claim 1, wherein the outer wall of the heat exchanger is composed of an inner lining and an expansion jacket hermetically connected to the outer side of the inner lining, the steam inlet is arranged on the expansion jacket, the heat exchange tubes are arranged in the inner lining, gaps for steam to enter are formed on the inner lining, and the gaps are arranged in the expansion jacket and are staggered with the steam inlet.

3. The alkaline evaporation plant of claim 1, wherein said heat exchange tubes are arranged in a triangular pattern within said heat exchanger.

4. The alkali evaporation device as claimed in claim 1, wherein the side wall of the heat exchanger is fixed with baffle plates which are arranged in a left-right staggered manner, the baffle plates are fixed through vertically arranged distance tubes, pull rods are sleeved in the distance tubes, threads are arranged at two ends of each pull rod, and the pull rods are fixed on the baffle plates through nuts matched with the pull rods.

5. The soda evaporating apparatus of claim 1, wherein said heat exchanging pipes are all the same length.

6. The alkali evaporation device according to claim 1, wherein the film distribution head is a cylindrical structure with openings at both ends, one end of the film distribution head is a necking end to be inserted into the heat exchange tube in a matching manner, one or more vertical slots which are annularly and uniformly distributed and are used for liquid to flow in are arranged on the side wall of the film distribution head, one end of each slot starts from the other end opposite to the necking end, the other end is positioned in the middle of the film distribution head and does not reach the end part of the necking end of the film distribution head.

7. The alkali evaporation device according to claim 6, wherein the slot is divided into a first slot section near the necking end and a second slot section at the necking end along a length direction of the film distribution head, the first slot section is an oblique slot, an included angle between two oblique side walls of the oblique slot is gradually changed from 60 ° to 30 ° from top to bottom, two side walls of the second slot section are parallel, widths of openings of the first slot section and the second slot section on one side of an inner wall of the film distribution head are the same, an opening of the first slot section on one side of an outer wall of the film distribution head is decreased from top to bottom until the widths of the openings are the same as those of the second slot section on one side of the outer wall of the film distribution head, and an opening of the second slot section on one side of the outer wall of the film distribution head is kept the same from top to bottom.

8. The soda evaporating apparatus of claim 1, wherein the steam inlet is disposed in a middle portion of a housing of the heat exchanger, a top portion of the housing of the heat exchanger is provided with a gas exhaust port, and a bottom portion of the housing is provided with a condensed water outlet.

9. The alkali evaporation device according to claim 1, wherein a pressure gauge connection port is arranged at the top of the shell of the heat exchanger, a drain port is arranged at the bottommost portion of the shell of the heat exchanger, an evaporator connector at the bottom of the heat exchanger is connected with a heat exchanger connection port at the top of the gas-liquid separation tank in a sealing mode, and a gasket are arranged between the evaporator connector and the heat exchanger connection port and are fastened and sealed through nuts and studs.

10. The alkali evaporation device according to claim 1, wherein a plurality of level meter ports are provided on a side wall of the gas-liquid separation tank, one of the level meter ports is located at the bottom of the gas-liquid separation tank, the other two level meter ports are located at the middle upper part of the gas-liquid separation tank, a manhole is provided on the side wall of the gas-liquid separation tank, the demister is a wire mesh demister and is obliquely provided below the steam outlet, a liquid inlet is provided on the side wall of the gas-liquid separation tank, and the liquid inlet is located below the demister.