CN212273967U - System for utilize high temperature flue gas to deoxidization water secondary for boiler - Google Patents

Abstract

The utility model provides an utilize high temperature flue gas to system of deoxidization water secondary deoxidization for boiler, belongs to the thermal power field, including a plurality of flue gas heat transfer unit, cloth water tank and the water storage box of establishing ties in proper order, high temperature flue gas carries out the heat exchange with the deoxidization water and heats the deoxidization in flue gas heat transfer unit, and later the deoxidization water reentrants and carries out a lot of heating deoxidization in the water distribution box, at last reentrant the water storage box and store. The utility model discloses make full use of the waste heat of high temperature flue gas carries out a lot of heating to the deaerated water, later recycle special construction's water distribution case makes steam and deaerated water carry out a lot of heat exchange again to form the multitime heating deoxidization to the deaerated water at the water distribution incasement, strengthened deoxidization efficiency and deoxidization effect greatly, not only can reduce the dissolved oxygen content in the deaerated water to below 16 micrograms per liter, but also improved the waste heat utilization of high temperature flue gas greatly.

Description

System for utilize high temperature flue gas to deoxidization water secondary for boiler

Technical Field

The utility model relates to the production of thermal power field deoxidization water, specific system that utilizes high temperature flue gas to deoxidization water secondary for boiler that says so.

Background

The deaerator is one of key equipment of a boiler and a heating system, for example, the deaerator has poor deaerating capability and causes serious loss to the corrosion of a boiler water supply pipeline, an economizer and other accessory equipment, and the caused economic loss is dozens or hundreds of times of the manufacturing cost of the deaerator. The deaerator has the main functions of: firstly, the water supply is heated to saturation temperature by utilizing the thermodynamic principle, dissolved gas in the water supply is removed, and secondly, the water supply temperature is improved, so that the thermal cycle efficiency of the unit is improved.

The deaerators equipped in the large-scale unit at present comprise a spray tray deaerator, a rotary film deaerator, a headless deaerator and the like. No matter which kind of oxygen-eliminating device, it basically all utilizes steam to heat the deoxidization, even use steam and demineralized water to pass through different mode contact heating, gets rid of the dissolved oxygen in the demineralized water, consequently, the contact surface and the contact mode of steam and demineralized water can direct influence deoxidization efficiency.

The design performance of the deaerator is index data obtained under ideal working conditions, but in actual production, considering the influences of factors such as cost, time, environmental temperature, matched pressure equipment and water quality, the design index is difficult to reach, for example, the deaerator of our company, in actual production, the dissolved oxygen content after deaerating by the deaerator is generally 40-60 micrograms per liter and is far higher than the standard value of 7 micrograms per liter.

SUMMERY OF THE UTILITY MODEL

In order to solve the problem that current oxygen-eliminating device leads to its deoxidization effect to be far below the standard because various factors influence in actual production, the utility model provides an utilize high temperature flue gas to the system of deoxidization water secondary deoxidization for the boiler, this system make full use of the waste heat of high temperature flue gas carry out a lot of heating to the deoxidization water, later recycle special construction's water distribution case makes steam and deoxidization water carry out the heat exchange many times again to the deoxidization effect has been strengthened greatly, can reduce the dissolved oxygen content in the deoxidization water to below 15 micrograms per liter.

The utility model discloses a solve the technical scheme that above-mentioned technical problem adopted and be: a system for secondarily deoxidizing boiler deaerated water by utilizing high-temperature flue gas comprises a plurality of flue gas heat exchange units, a water distribution tank and a water storage tank which are sequentially connected in series, wherein the high-temperature flue gas exchanges heat with deaerated water in the flue gas heat exchange units to heat and deaerate the high-temperature flue gas, the deaerated water enters the water distribution tank again to be heated and deaerated for a plurality of times and finally enters the water storage tank to be stored, the flue gas heat exchange units comprise conical shells, conical first heat exchange coils are arranged in the shells, small gaps are formed between the first heat exchange coils and the inner walls of the shells to form deaerated water heat exchange channels, each first heat exchange coil is a conical coil formed by spirally arranging a hollow copper pipe, the diameter of the bottom of each conical coil is larger than that of the top of the conical coil, a spiral first spiral line is formed between the hollow copper pipes on the surfaces of the conical coils, and a high-temperature flue gas discharge pipe penetrating out, the bottom of the first heat exchange coil is provided with a high-temperature flue gas inlet pipe penetrating out of the bottom end of the shell;

the conical top end of the shell is provided with a deoxygenated water passing device, the deoxygenated water passing device comprises a conical shell formed by an outer conical shell and an inner conical shell which are nested with each other, the outer conical shell and the inner conical shell are connected into a whole through a plurality of connecting pieces, a deoxygenated water inlet channel is formed between the outer conical shell and the inner conical shell, the bottom end of the deoxygenated water inlet channel faces the conical top end of the first heat exchange coil, and therefore deoxygenated water flowing out of the deoxygenated water inlet channel falls onto the surface of the first heat exchange coil; the inner conical shell is hollow, so that a steam channel is formed, steam is fed into the steam channel through a steam feed pipe penetrating through the outer conical shell and the inner conical shell, and deaerated water enters the deaerated water heat exchange channel through a gap between the bottom of the conical shell of the device and the conical top end of the first heat exchange coil, so that the deaerated water is heated, and meanwhile, the flow of the deaerated water on the surface of the first heat exchange coil is promoted;

the smoke heat exchange units which are sequentially connected in series from top to bottom in the height direction, the deoxygenated water on the smoke heat exchange unit at the highest position is connected with the deoxygenated water pipe through the deoxygenated water joint at the top of the smoke heat exchange unit, and the high-temperature smoke discharge pipe on the smoke heat exchange unit is connected with the smoke purification treatment device; among the other flue gas heat exchange units, a high-temperature flue gas discharge pipe on the flue gas heat exchange unit positioned below is communicated with a high-temperature flue gas inlet pipe on the flue gas heat exchange unit adjacent to the upper side of the high-temperature flue gas discharge pipe, and the deaerated water on the flue gas heat exchange unit positioned below extends into the shell of the flue gas heat exchange unit adjacent to the upper side of the high-temperature flue gas heat exchange unit through the device, so that the deaerated water in the flue gas heat exchange unit above the high-temperature flue gas heat exchange unit flows into the outer wall of the conical top end of the first; and the bottom of the flue gas heat exchange unit positioned at the lowest part is used for sending deoxygenated water into the water distribution hollow plate at the top of the water distribution box through the drain pipe I, and then the deoxygenated water is sprayed into the water distribution box through a plurality of atomizing spray heads arranged on the bottom surface of the water distribution hollow plate.

The utility model discloses an optimal embodiment does, the oxygen-eliminating water swivel includes that the interior shrouding of steam passage top confined and the top with outer conical shell of passing through the device with the oxygen-eliminating water on the flue gas heat transfer unit of highest point is connected and covers the outer shrouding of interior shrouding in it, and forms the intake antrum between interior shrouding and the outer shrouding, and the intake antrum pours into the oxygen-eliminating water into to it through an inlet tube.

The other preferred embodiment of the utility model is that the bottom of the water distribution tank is communicated with the water storage tank through a drain pipe II, a water separator is arranged in the water distribution tank, the water separator comprises a horizontally arranged water distribution plate, the water distribution tank is divided into an upper chamber and a lower chamber by the water distribution plate, a plurality of water distribution holes which are communicated with the upper chamber and the lower chamber and used for water guiding are distributed on the water distribution plate, the section of each water distribution hole is in a hyperbolic shape, a gas collecting hood which is in a reversed circular truncated cone shape and surrounds the water distribution hole is arranged at the bottom of each water distribution hole, the gas collecting hood is matched with the lower part of the water distribution hole to form a gas gathering cavity, a gas spraying component is arranged in the gas gathering cavity, the gas spraying component comprises a first gas spraying disc and a second gas spraying disc which is arranged on the first gas spraying disc through a connecting rod, wherein the first gas spraying disc shields an opening at the bottom of the gas gathering cavity, a gap is reserved between the first gas spraying disc, the steam sprayed by the first gas spraying holes is obliquely and upwards sprayed to the surface of the gas collecting hood, and is collided and converged at the top center of the gas collecting cavity after being rebounded by the surface of the gas collecting hood and the inner wall of the bottom of the water distribution hole in sequence to form semi-annular steam flow upwards along the water distribution hole, so that the deoxygenated water entering the water distribution hole is heated for the first time;

the first air injection holes in the first air injection disc are supplied with water vapor through first steam inlet pipes, the first steam inlet pipes are communicated with steam outlets of the conical second heat exchange coils, the second heat exchange coils are conical coils formed by spirally arranging hollow copper pipes, the diameter of the bottom of each conical coil is larger than that of the top of each conical coil, spiral second spiral lines are formed among the hollow copper pipes on the surfaces of the conical coils, the tops of the second heat exchange coils are positioned in openings at the bottoms of the air gathering cavities, so that deoxygenated water entering the water distribution holes falls onto the surfaces of the second heat exchange coils through the openings, and secondary heat exchange is carried out on the deoxygenated water and steam in the second heat exchange coils in the downward flowing process along the outer walls of the second heat exchange coils; a first steam injection pipe for feeding steam into the second heat exchange coil is arranged at the bottom of the second heat exchange coil;

the second air injection plate is a conical part extending into the narrow part of the middle part of the water distribution hole, and second air injection holes inclining upwards are distributed around the second air injection plate, so that steam sprayed by the second air injection holes is obliquely blown onto the inner wall of the middle part of the water distribution hole to form an air seal for the gas gathering cavity, and simultaneously, a low-pressure area is formed at the narrow part of the middle part of the water distribution hole to promote the steam in the gas gathering cavity to be sprayed upwards along the water distribution hole so as to be contacted with the deaerated water of the water distribution hole for heating; the second gas injection holes are injected with steam by a second steam injection pipe.

Another preferred embodiment of the utility model is that a row of second steam branch pipes uniformly supplied with steam by the first steam main pipe are arranged in the lower chamber of the water distribution box, and a first steam branch pipe is arranged below the gap between two adjacent second steam branch pipes, and all the first steam branch pipes are uniformly supplied with steam by the second steam main pipe; the water distribution holes on the water distribution plate are uniformly distributed in rows, and each water distribution hole corresponds to one second steam branch pipe and one first steam branch pipe, so that a first steam injection pipe below any one water distribution hole in the row is communicated with the first steam branch pipe, and a second steam injection pipe is communicated with the second steam branch pipe; the first steam injection pipe and the second steam injection pipe form a third deoxygenated water heat exchange area, and the second steam branch pipe and the first steam branch pipe form a fourth deoxygenated water heat exchange area.

The utility model discloses a another preferred embodiment does, the water distribution hole includes the outer narrow district that expands on upper portion and meet water district, middle part and the outer diffusion water district of bottom to make the oxygen-removed water sweep by steam from last down when narrow district's process, and the lateral wall dispersion that is pasting the outer diffusion water district has improved heating efficiency downwards.

Another preferred embodiment of the utility model is that a third air injection disc is fixed on the connecting rod, and a third air injection hole is obliquely arranged around the side surface of the third air injection disc, so that steam sprayed by the third air injection hole obliquely impacts the inner wall of the lower part of the water distribution hole and then rebounds upwards; the third gas injection holes are also injected with steam by the second steam injection pipes;

the center of the conical bottom of the second air injection disc is provided with a conical pit so as to form an annular fin at the bottom of the second air injection disc; the contact point of steam ejected by a third air ejecting hole on a third air ejecting disc and the side wall of the lower part of a water distribution hole is defined as a steam inflection point, the tangential direction of the steam inflection point is defined as a datum line, the connecting line of the third air ejecting hole and the steam inflection point is defined as a ray A, the connecting line of the top of a conical pit and the steam inflection point is defined as a ray B, the included angle between the ray A and the datum line is an acute angle and is larger than the included angle between the ray B and the datum line, and meanwhile, the included angle between the ray B and the vertical direction is smaller than the included angle between the side wall of the conical pit and the vertical direction, so that after steam flow ejected by the third air ejecting hole rebounds against the inner wall of the lower part of the water distribution hole, part of the steam.

The utility model discloses a another kind of preferred embodiment does, second heat exchange coil sets up on metal mesh plate, and this metal mesh plate is the metal sheet of edge-fixed on the water distribution box inner wall, and the dense netted plate structure that forms that has the hole that permeates water that runs through its thickness direction on the metal sheet.

The utility model discloses a another preferred embodiment does, be connected with 1-4 driving levers on the conical top of the jet-propelled dish of second, the bottom of driving lever articulate in the jet-propelled dish top of second, the top extends to the upper portion in water distribution hole to lean on the middle part in water distribution hole to make under the blowing of vapor produce stir, prevent that the deoxidization water from producing the water film that blocks the deoxidization underwater flow in water distribution hole middle part.

Compared with the prior art, the utility model discloses following beneficial effect has:

1) the utility model makes full use of the waste heat of the high-temperature flue gas to heat the deaerated water for many times, and then the water distribution box with a special structure is reused to make the steam and the deaerated water perform heat exchange for many times, thereby greatly enhancing the deaerating effect, not only reducing the dissolved oxygen content in the deaerated water to below 15 micrograms per liter, but also greatly improving the waste heat utilization of the high-temperature flue gas; the core of the water distribution tank is the water distribution holes on the water distribution plate in the water distribution tank and the air injection assembly arranged in each water distribution hole, and the special structure of the air injection assembly is matched with the shape and the structure of the water distribution holes, so that the deaerated water is heated and deaerated for multiple times in the water distribution tank, and the deaerated efficiency and the deaerated effect are improved;

2) the utility model designs the water distribution holes into a hyperbolic shape, so that the deoxygenated water from top to bottom can be uniformly dispersed along the inner wall of the water distribution holes under the blowing of the lower steam in the middle narrow area, the contact area with the steam is increased, and the heating effect is improved; the gas collecting hood arranged at the lower part of the water distribution hole forms a gas collecting cavity for accommodating the gas spraying assembly, so that the temperature in the gas collecting cavity can be increased, and the heating effect is improved when the deoxygenated water passes through the gas collecting cavity;

3) the utility model discloses an among the jet-propelled subassembly, first fumarole spun steam on the first fumarole can form the semi-annular steam flow in gathering the gas chamber to with gather the abundant contact heating of the deoxidization water that the gas chamber inner wall flows along, and the second fumarole extends to the narrow department in water distribution hole middle part, the downthehole spun steam of second fumarole above that, partly form the atmoseal to lower part gas gathering chamber, another part is then upwards spraying, play the drainage effect that the steam upward movement in the guide gas gathering chamber, not only play further heating effect, and in the process of rising, fully contact the heating with the deoxidization water;

4) the third air injection disc with the auxiliary function is also arranged in the air injection assembly, and steam sprayed from the third air injection holes on the third air injection disc can be matched with the conical pits at the bottom of the second air injection disc to form circulation in the air gathering cavity, so that the heating effect is improved;

5) the utility model discloses through the deoxidization water of water distribution hole and air gathering chamber back downflow, be along the downward flow of surface of second heat transfer coil pipe, in this process, carry out the heat exchange with the steam in the second heat transfer coil pipe to once more heat the deoxidization, improved the deoxidization effect;

6) the utility model discloses in, to the first steam injection pipe of the downthehole supply steam of first jet-propelled and to the downthehole second steam injection pipe of supplying with steam of second jet-propelled form the deoxidization water third heat transfer area that is in second heat transfer coil pipe below respectively, and have the first steam branch pipe and the second steam branch pipe of supplying with steam in these first steam injection pipes and the second steam injection pipe below them, these first steam branch pipe and second steam branch pipe form the fourth heat transfer area below deoxidization water third heat transfer area, thereby make the deoxidization water at top-down's in-process, through heating or heat transfer process of at least quartzy, the deoxidization effect has been improved greatly, through the experiment demonstration, can reduce the dissolved oxygen content in the deoxidization water to the standard below 15 micrograms per liter, compare with current index, promotion by a wide margin has been had.

Drawings

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

FIG. 2 is a schematic view of a connection structure of a flue gas heat exchange unit and a deoxygenated water passing device;

FIG. 3 is a schematic structural view of a deoxygenated water passing device and a deoxygenated water joint;

FIG. 4 is a schematic structural view of a water distribution tank;

FIG. 5 is an overall schematic view of multi-stage heating of deoxygenated water in the water distribution tank;

FIG. 6 is a schematic sectional view of the water distribution holes;

FIG. 7 is a schematic structural view of a gas injection assembly;

FIG. 8 is a schematic view of the air injection assembly and the water distribution holes;

FIG. 9 is a schematic view of the combination of FIG. 8 with a second heat exchange coil;

reference numerals: 1. a flue gas heat exchange unit, 101, a shell, 102, a first heat exchange coil, 103, a first spiral line, 104, a deoxygenated water heat exchange channel, 105, a high-temperature flue gas discharge pipe, 106, a high-temperature flue gas inlet pipe, 2, a deoxygenated water passing device, 201, an outer conical shell, 202, an inner conical shell, 203, a deoxygenated water inlet channel, 204, a connector, 205, a steam channel, 206, a steam feed pipe, 3, a deoxygenated water joint, 301, an inner sealing plate, 302, an outer sealing plate, 303, a water inlet cavity, 304, a water inlet pipe, 4, a water distribution box, 401, a water distribution hollow plate, 402, a second steam branch pipe, 403, a first steam branch pipe, 404, a water discharge pipe II, 405, a metal mesh plate, 406, an upper chamber, 407, a gas collection chamber, 408, a water discharge pipe I, 5, a water distributor, 501, a water distribution plate, 502, a water distribution hole, 5021, an outer expansion water collection region, 5022, a narrow region, 5023, an outer diffusion water, 504. the steam injection device comprises a gas gathering cavity, 505, an opening, 6, a gas injection assembly, 601, a first gas injection disc, 602, a first gas injection hole, 603, a first steam inlet pipe, 604, a third gas injection disc, 605, a third gas injection hole, 606, a connecting rod, 607, a second gas injection disc, 608, a second steam injection pipe, 609, a conical pit, 6010, a second gas injection hole, 6011, a deflector rod, 7, a second heat exchange coil pipe, 701, a second spiral line, 702, a first steam injection pipe, 8 and a water storage tank.

Detailed Description

The technical solution of the present invention will be further elaborated with reference to the following specific embodiments.

Example 1

As shown in fig. 1-3, a system for secondarily deoxidizing water for a boiler by using high-temperature flue gas comprises a plurality of flue gas heat exchange units 1, a water distribution tank 4 and a water storage tank 8 which are sequentially connected in series, wherein the high-temperature flue gas exchanges heat with the deoxidizing water in the flue gas heat exchange units 1 to deoxidize the deoxidizing water, then the deoxidizing water enters the water distribution tank 4 to deoxidize the deoxidizing water by heating for many times, and finally enters the water storage tank 8 to be stored, the flue gas heat exchange units 1 comprise conical shells 101, conical first heat exchange coils 102 are arranged in the shells 101, a small gap is formed between the first heat exchange coils 102 and the inner walls of the shells 101 to form a deoxidizing water heat exchange channel 104, the first heat exchange coils 102 are conical coils formed by spirally arranging hollow copper pipes, the bottom diameter of each conical coil is larger than the top diameter of each conical coil, and spiral first rotary lines 103 are formed between the hollow copper pipes on the surfaces of the conical coils, a high-temperature flue gas discharge pipe 105 penetrating through the conical top end of the shell 101 is arranged at the conical top end of the first heat exchange coil 102, and a high-temperature flue gas inlet pipe 106 penetrating through the bottom end of the shell 101 is arranged at the bottom of the first heat exchange coil 102;

the conical top end of the shell 101 is provided with a deoxygenated water passing device 2, the deoxygenated water passing device 2 comprises a conical shell formed by an outer conical shell 201 and an inner conical shell 202 which are nested with each other, the outer conical shell 201 and the inner conical shell 202 are connected into a whole through a plurality of connecting pieces 204, a deoxygenated water inlet channel 203 is formed between the outer conical shell 201 and the inner conical shell 202, the bottom end of the deoxygenated water inlet channel 203 faces the conical top end of the first heat exchange coil 102, and therefore deoxygenated water flowing out of the deoxygenated water inlet channel falls onto the surface of the first heat exchange coil 102; the inner conical shell 202 is hollow, so that a steam channel 205 is formed, steam is fed into the steam channel 205 through a steam feed pipe 206 penetrating through the outer conical shell 201 and the inner conical shell 202, and deoxygenated water enters the deoxygenated water heat exchange channel 104 through a gap between the conical shell bottom of the device 2 and the conical top end of the first heat exchange coil 102, so that the deoxygenated water is heated, and the flow of the deoxygenated water on the surface of the first heat exchange coil 102 is promoted;

the smoke heat exchange units 1 which are sequentially connected in series from top to bottom in the height direction, the deoxygenated water on the smoke heat exchange unit 1 at the highest position is connected with a deoxygenated water pipe through a deoxygenated water joint 3 at the top of the device 2, and a high-temperature smoke discharge pipe 105 on the device is connected with a smoke purification treatment device; in the rest of the flue gas heat exchange units 1, the high-temperature flue gas discharge pipe 105 on the flue gas heat exchange unit 1 positioned below is communicated with the high-temperature flue gas inlet pipe 106 on the flue gas heat exchange unit 1 adjacent above, and the deoxygenated water on the flue gas heat exchange unit 1 positioned below extends into the shell 101 of the adjacent flue gas heat exchange unit 1 above through the device 2, so that the deoxygenated water in the flue gas heat exchange unit 1 above flows into the outer wall of the conical top end of the first heat exchange coil 102 inside through the deoxygenated water inlet channel 203 of the device 2; the bottom of the flue gas heat exchange unit 1 positioned at the lowest part is used for sending deoxygenated water into the water distribution hollow plate 401 at the top of the water distribution box 4 through a drain pipe I408, and then the deoxygenated water is sprayed into the water distribution box 4 through a plurality of atomizing nozzles arranged on the bottom surface of the water distribution hollow plate 401.

In this embodiment, the bottom surface of casing 101 is the arcwall face that is low from edge high center to make the deoxidization water can assemble at the bottom surface center, and enter into next flue gas heat transfer unit 1 through deoxidization water entering channel 203 of deoxidization water through device 2.

In this embodiment, a small gap is formed between the first heat exchange coil 102 and the inner wall of the casing 101 to form a deoxygenated water heat exchange channel 104, where the small gap is: the distance between the two is not more than 2cm, and is optimally 0.5-1.5, which is determined mainly by the oxygen-removing water demand in the actual production.

In this embodiment, the number of the flue gas heat exchange units 1 is at least 3, and certainly, the number of the flue gas heat exchange units 1 may be more, the high-temperature flue gas inlet pipe 106 of the lowest flue gas heat exchange unit 1 is connected to a high-temperature flue gas pipeline, and the high-temperature flue gas outlet pipe 105 of the uppermost flue gas heat exchange unit 1 is connected to the existing flue gas purification treatment device.

In this embodiment, the steam channel 205 is used to inject steam, to promote the flow of the deoxygenated water, and to directly heat the deoxygenated water.

The above is the basic embodiment of the present invention, and further improvement, optimization and limitation can be made on the above basis, so as to obtain the following preferred embodiments:

example 2

This embodiment is an improved scheme based on embodiment 1, and its basic structure is the same as embodiment 1, except that: as shown in fig. 1 and 3, the deaerated water joint 3 includes an inner sealing plate 301 which closes the top end of a steam channel 205 of the highest flue gas heat exchange unit 1, and an outer sealing plate 302 which is connected with the top end of the outer conical shell 201 and covers the inner sealing plate 301 therein, wherein an inlet cavity 303 is formed between the inner sealing plate 301 and the outer sealing plate 302, and the inlet cavity 303 is filled with deaerated water through an inlet pipe 304.

In this embodiment, the inlet tube 304 of the deoxygenated water joint 3 is connected with the deoxygenated water pump, and the deoxygenated water pump pumps the deoxygenated water which is not deoxygenated by the existing deoxygenator or the deoxygenated water which is once deoxygenated by the deoxygenator.

Example 3

This embodiment is another modified scheme based on embodiment 1, and its basic structure is the same as embodiment 1, except that: as shown in fig. 1 and 4-9, the bottom of the water distribution tank 4 is communicated with the water storage tank 8 through a water discharge pipe ii 404, a water distributor 5 is arranged in the water distribution tank 4, the water distributor 5 comprises a water distribution plate 501 arranged horizontally, the water distribution plate 501 divides the interior of the water distribution tank 4 into an upper chamber 406 and a lower chamber 407, a plurality of water distribution holes 502 for water distribution are distributed on the water distribution plate 501 and are communicated with the upper chamber 406 and the lower chamber 407, the cross section of each water distribution hole 502 is hyperbolic, an inverted circular truncated cone-shaped gas collection cover 503 surrounding the water distribution holes 502 is arranged at the bottom of each water distribution hole 502, the gas collection cover 503 is matched with the lower part of the water distribution holes 502 to form a gas collection chamber 504, a gas injection assembly 6 is arranged in the gas collection chamber 504, the gas injection assembly 6 comprises a first gas injection plate 601 and a second gas injection plate 607 arranged on the first gas injection plate 601 through a connecting rod 606, wherein the first gas injection plate 601 shields the opening 505 at, a gap is reserved between the first air jet disc and the air collecting cover, a plurality of first air jet holes 602 which incline upwards are arranged on the surface surrounding the first air jet disc 601, so that steam sprayed out from the first air jet holes 602 is obliquely and upwards sprayed to the surface of the air collecting cover 503, and is collided and converged at the top center of the air collecting cavity 504 after being rebounded by the surface of the air collecting cover 503 and the inner wall of the bottom of the water distribution hole 502 in sequence to form semi-annular steam flow which upwards flows along the water distribution hole 502, and thus deaerated water entering the water distribution hole 502 is heated for one time;

the first air injection holes 602 on the first air injection plate 601 are supplied with water vapor by a first steam inlet pipe 603, the first steam inlet pipe 603 is communicated with a steam outlet of a conical second heat exchange coil 7, the second heat exchange coil 7 is also a conical coil formed by spirally arranging a hollow copper pipe and having a diameter at the bottom larger than that at the top, a spiral second spiral line 701 is formed between the hollow copper pipes on the surface of the conical coil, the top of the second heat exchange coil 7 is positioned in an opening 505 at the bottom of the air gathering cavity 504, so that deoxygenated water entering the water distribution hole 502 falls onto the surface of the second heat exchange coil 7 through the opening 505, and performs secondary heat exchange with steam in the second heat exchange coil 7 in the process of flowing downwards along the outer wall of the second heat exchange coil 7; a first steam injection pipe 702 for feeding steam into the second heat exchange coil 7 is arranged at the bottom of the second heat exchange coil;

the second air jet disc 607 is a conical member extending into the narrow part of the middle of the water distribution hole 502, and second air jet holes 6010 inclined upwards are distributed around the second air jet disc 607, so that steam ejected from the second air jet holes 6010 is obliquely blown onto the inner wall of the middle of the water distribution hole 502 to form an air seal to the gas gathering cavity 504, and simultaneously, a low pressure region is formed at the narrow part of the middle of the water distribution hole 502 to promote the steam in the gas gathering cavity 504 to be ejected upwards along the water distribution hole 502, so as to contact with the deoxygenated water of the water distribution hole 502 for heating; the second gas injection holes 6010 are injected with the vapor from the second vapor injection pipe 608.

In this embodiment, the first gas injection holes 602 on the first gas injection plate 601 are two layers of annular gas injection holes at different heights, but may be 3 layers or more; the second gas injection holes 6010 of the second gas injection tray 607 are also two layers of annular gas injection holes at different heights, but may be 3 layers or more.

In the present embodiment, the steam pressure inside the second steam injection pipe 608 is greater than the steam pressure inside the first steam injection pipe 602. Typically 1.1 to 1.4 times the vapor pressure within the first vapor injection pipe 602.

In this embodiment, the steam in the second steam injection pipe 608 is preferably supplied intermittently, i.e., 1s is stopped for every 1-2s of steam supplied.

Example 4

This embodiment is an improved scheme based on embodiment 3, and its basic structure is the same as embodiment 3, except that: as shown in fig. 4 and 5, a row of second steam branch pipes 402 uniformly supplied with steam by a first steam header pipe is arranged in a lower chamber 407 of the water distribution box 4, a first steam branch pipe 403 is arranged below a gap between two adjacent second steam branch pipes 402, and all the first steam branch pipes 403 are uniformly supplied with steam by the second steam header pipe; the water distribution holes 502 on the water distribution plate 501 are uniformly distributed in rows, and each water distribution hole 502 corresponds to one second steam branch pipe 402 and one first steam branch pipe 403, so that the first steam injection pipe 702 below any one water distribution hole 502 in the row is communicated with the first steam branch pipe 403, and the second steam injection pipe 608 is communicated with the second steam branch pipe 402; the first steam injection pipe 702 and the second steam injection pipe 608 form a third heat exchange area for the deoxygenated water, and the second steam branch pipe 402 and the first steam branch pipe 403 form a fourth heat exchange area for the deoxygenated water.

In this embodiment, the diameter of the first steam branch pipe 403 is not smaller than the gap between the two second steam branch pipes 402, so that the deoxygenated water inevitably falls onto the surface of the first steam branch pipe 403 or the second steam branch pipe 402 during the falling process, and further heat exchange occurs; the middle position of each first steam branch pipe 403 and the adjacent second steam branch pipe 402 corresponds to the center of one row of water distribution holes 502, so that the first steam injection pipe 702 and the second steam injection pipe 608 below the row of water distribution holes 502 can be vertically and downwardly communicated with the first steam branch pipe 403 or the second steam branch pipe 402 respectively, thereby forming a row of staggered first steam injection pipes 702 and second steam injection pipes 608 in a vertical plane, the first steam injection pipe 702 below the adjacent two rows of water distribution holes 502 is connected to one first steam branch pipe 403, and the second steam injection pipe 608 below the adjacent two rows of water distribution holes 502 is connected to one second steam branch pipe 402. The second steam injection pipe 608 is partially disposed in the connection rod 606 and communicates with the second gas injection hole 6010, and the remaining portion extends downward through the inner cavity of the second heat exchange coil 7.

Example 5

This embodiment is another modified scheme based on embodiment 3, and its basic structure is the same as embodiment 3, except that: as shown in fig. 6, the water distribution holes 502 include an upper outward-diffusion water-facing area 5021, a middle narrow area 5022, and a bottom outward-diffusion water area 5023, so that the deoxygenated water is swept from the bottom up by the steam when passing through the narrow area 5022, and is dispersed downward against the sidewall of the outward-diffusion water area 5023, thereby improving the heating efficiency.

In this embodiment, the diameter of the narrowest part of the narrow region 5022 is 0.5-1.5cm, the maximum diameter of the top of the outward-expanding water-facing region 5021 is greater than the maximum diameter of the bottom of the outward-diffusing water-facing region 5023, the maximum diameter of the top of the outward-expanding water-facing region 5021 is 0.8-1.2 times the depth of the water distribution holes 502, and the maximum diameter of the bottom of the outward-diffusing water-facing region 5023 is 0.4-0.6 times the depth of the water distribution holes 502.

In this embodiment, the depth of the water distribution holes 502 is actually the thickness of the water distribution plate 501.

In this embodiment, the water distribution holes 502 are processed by a bidirectional reaming method, that is, holes are drilled in the water distribution plate 501, and then reaming operations are performed at two ends of the drilled holes respectively, where the reaming standard is that according to the diameter and depth parameter indexes of the water distribution holes 502, a certain depth of the holes corresponds to a diameter parameter, and reaming operations are performed according to the parameter.

Example 6

This embodiment is another modified scheme based on embodiment 3, and its basic structure is the same as embodiment 3, except that: as shown in fig. 7-9, a third air injection plate 604 is fixed on the connecting rod 606, and a third air injection hole 605 is obliquely arranged around the side surface of the third air injection plate 604, so that steam sprayed from the third air injection hole 605 obliquely impacts the inner wall of the lower part of the water distribution hole 502 and then rebounds upwards; the third gas injection holes 605 are also injected with steam by the second steam injection pipe 608;

the conical bottom center of the second jet disk 607 is provided with a conical concave pit 609 so as to form an annular fin at the bottom of the second jet disk 607; the contact point of steam ejected from the third air ejection hole 605 on the third air ejection disc 604 and the lower side wall of the water distribution hole 502 is defined as a steam inflection point, the tangential direction at the steam inflection point is defined as a reference line, the connecting line of the third air ejection hole 605 and the steam inflection point is defined as a ray A, the connecting line of the vertex of the conical pit 609 and the steam inflection point is defined as a ray B, the included angle between the ray A and the reference line is an acute angle and is larger than the included angle between the ray B and the reference line, and meanwhile, the included angle between the ray B and the vertical direction is smaller than the included angle between the side wall of the conical pit 609 and the vertical direction, so that after steam flow ejected from the third air ejection hole 605 rebounds against the lower inner wall of the water distribution hole 502, a part of the steam flow can form a circulation flow in.

In this embodiment, the angle between the ray A and the reference line is generally 50-70 °, the angle between the ray B and the reference line is generally 35-45 °, the angle between the ray B and the vertical direction is generally 30-50 °, and the angle between the sidewall of the conical pit 609 and the vertical direction is generally 48-70 °.

Example 7

This embodiment is another modified scheme based on embodiment 3, and its basic structure is the same as embodiment 3, except that: as shown in fig. 7 to 9, the second heat exchanging coil 7 is disposed on a metal mesh plate 405, the metal mesh plate 405 is a metal plate whose edge is fixed on the inner wall of the water distribution box 4, and a mesh plate structure formed by water permeable holes penetrating through the metal plate in the thickness direction is densely distributed on the metal plate.

Example 8

This embodiment is another modified scheme based on embodiment 3, and its basic structure is the same as embodiment 3, except that: as shown in fig. 7 to 9, 1 to 4 deflector rods 6011 are connected to the conical top of the second air jet disc 607, the bottom of the deflector rods 6011 are hinged to the top of the second air jet disc 607, and the top end of the deflector rods 6011 extends to the upper part of the water distribution holes 502 and leans against the middle part of the water distribution holes 502, so that the deflector rods are moved by the blowing of the water vapor, and the oxygen-removed water is prevented from generating a water film in the middle of the water distribution holes 502 to block the downward flow of the oxygen-removed water.

The utility model discloses an in above each embodiment, because steam enters into water distribution box 3 in, consequently lead to the atmospheric pressure in it to be bigger and bigger, so, need set up the atmospheric pressure valve at water distribution box 3's top for it maintains a invariable scope to balance atmospheric pressure in it.

In order to verify the oxygen removing effect of the utility model, the following oxygen removing experiment is specially made:

comparative example 1: taking a spinning membrane deaerator of Yizigao group thermoelectricity company as a comparative example 1, namely detecting the dissolved oxygen content of deaerated water discharged from a drain pipe of the spinning membrane deaerator;

comparative example 2: the deoxygenated water after deoxygenation in comparative example 1 is guided into comparative example 1 again for secondary deoxygenation, namely: feeding the deoxygenated water discharged from the drain pipe of the rotary membrane deaerator back to the rotary membrane deaerator again for deaerating, and finally deaerating the deoxygenated water twice continuously through the rotary membrane deaerator to detect the content of dissolved oxygen in the deoxygenated water;

comparative example 3: the deoxygenated water after the secondary deoxygenation of comparative example 2 was again led into comparative example 1 to be deoxygenated for three times, namely: continuously deoxidizing the deoxidized water for three times through a rotary membrane deaerator, and detecting the dissolved oxygen content in the deoxidized water;

experimental example 1: introducing the deoxygenated water deoxygenated by the comparative example 1 into the embodiment 4 of the utility model; in embodiment 4, the flue gas heat exchange units 1 are three groups, each group has a height of 1.5 m, the taper of the first heat exchange coil 102 is 145 °, and the diameter of the hollow copper tube forming the first heat exchange coil 102 is 3 cm; the height of the second heat exchange coil 7 is 0.5 m, and the diameter of the hollow copper pipe forming the second heat exchange coil 7 is 1 cm.

When the dissolved oxygen content is detected, a scheme of measuring and averaging for multiple times in different periods is adopted, namely: in the normal operation process, taking deoxygenated water once every 30min as a sample, detecting the dissolved oxygen content in the sample, taking 10 times in total, taking the average value as the dissolved oxygen content, and detecting:

the dissolved oxygen content of comparative example 1 was 58.1 micrograms per liter, the dissolved oxygen content of comparative example 2 was 48.7 micrograms per liter, and the dissolved oxygen content of comparative example 3 was 12.5 micrograms per liter; the dissolved oxygen content of experimental example 1 was 15.2 micrograms per liter;

according to the experimental data, the utility model discloses be equivalent to the effect after establishing ties three current rotary film deaerators of group, nevertheless compare in the series connection of three rotary film deaerators of group, the cost is lower, make full use of the waste heat of the coal-fired high temperature flue gas that produces of steam power plant moreover.

Claims (8)

1. The utility model provides an utilize high temperature flue gas to system of deoxidization water secondary deoxidization for boiler, this system includes flue gas heat transfer unit (1), cloth water tank (4) and water storage box (8) that a plurality of is established ties in proper order, and wherein, high temperature flue gas carries out heat exchange heating deoxidization with the deoxidization water in flue gas heat transfer unit (1), and later the deoxidization water reenters and carries out a lot of heating deoxidization in water distribution box (4), and it stores its characterized in that to reenter water storage box (8) at last: the smoke heat exchange unit (1) comprises a conical shell (101), a conical first heat exchange coil (102) is arranged in the shell (101), a small gap is formed between the first heat exchange coil (102) and the inner wall of the shell (101) to form a deaerated water heat exchange channel (104), the first heat exchange coil (102) is a conical coil formed by spirally arranging hollow copper pipes, the diameter of the bottom of the conical coil is larger than that of the top of the conical coil, a spiral first spiral line (103) is formed between the hollow copper pipes on the surface of the conical coil, a high-temperature smoke discharge pipe (105) penetrating through the conical top end of the shell (101) is arranged at the conical top end of the first heat exchange coil (102), and a high-temperature smoke inlet pipe (106) penetrating through the bottom end of the shell (101) is arranged at the bottom of the first heat exchange coil (;

the device is characterized in that a deoxygenated water passing device (2) is arranged at the conical top end of the shell (101), the deoxygenated water passing device (2) comprises a conical shell formed by an outer conical shell (201) and an inner conical shell (202) which are nested with each other, the outer conical shell (201) and the inner conical shell (202) are connected into a whole through a plurality of connecting pieces (204), a deoxygenated water inlet channel (203) is formed between the outer conical shell and the inner conical shell, and the bottom end of the deoxygenated water inlet channel (203) faces the conical top end of the first heat exchange coil (102), so that deoxygenated water flowing out of the deoxygenated water inlet channel falls onto the surface of the first heat exchange coil (102); the inner conical shell (202) is hollow, so that a steam channel (205) is formed, steam is fed into the steam channel (205) through a steam feed pipe (206) penetrating through the outer conical shell (201) and the inner conical shell (202), and deoxygenated water enters the deoxygenated water heat exchange channel (104) through a gap between the conical shell bottom of the device (2) and the conical top of the first heat exchange coil (102), so that the deoxygenated water is heated, and meanwhile, the flow of the deoxygenated water on the surface of the first heat exchange coil (102) is promoted;

the smoke heat exchange units (1) which are sequentially connected in series from top to bottom in the height direction, the deoxygenated water on the smoke heat exchange unit (1) at the highest position is connected with a deoxygenated water pipe through a deoxygenated water joint (3) at the top of the device (2), and a high-temperature smoke discharge pipe (105) on the device is connected with a smoke purification treatment device; among the rest flue gas heat exchange units (1), a high-temperature flue gas discharge pipe (105) on the flue gas heat exchange unit (1) positioned below is communicated with a high-temperature flue gas inlet pipe (106) on the flue gas heat exchange unit (1) adjacent to the upper side of the flue gas heat exchange unit, and deoxygenated water on the flue gas heat exchange unit (1) positioned below extends into a shell (101) of the flue gas heat exchange unit (1) adjacent to the upper side of the flue gas heat exchange unit through a device (2), so that the deoxygenated water in the flue gas heat exchange unit (1) above the shell flows into the outer wall of the conical top end of a first heat exchange coil (102) through a deoxygenated water inlet channel (203) of the device (2); and the bottom of the flue gas heat exchange unit (1) positioned at the lowest part is used for sending deoxygenated water into the water distribution hollow plate (401) at the top of the water distribution tank (4) through a drain pipe I (408), and then a plurality of atomizing nozzles arranged on the bottom surface of the water distribution hollow plate (401) are sprayed into the water distribution tank (4).

2. The system for secondarily deoxidizing water for boilers by using high-temperature flue gas as claimed in claim 1, wherein: the deaerated water joint (3) comprises an inner closed steam channel (205) with the top end of the steam channel (205) of the smoke heat exchange unit (1) at the highest position passing through the device (2), an outer sealing plate (302) connected with the top end of the outer conical shell (201) and covering the inner sealing plate (301) in the outer sealing plate, a water inlet cavity (303) is formed between the inner sealing plate (301) and the outer sealing plate (302), and deaerated water is injected into the water inlet cavity (303) through a water inlet pipe (304).

3. The system for secondarily deoxidizing water for boilers by using high-temperature flue gas as claimed in claim 1, wherein: the bottom of the water distribution tank (4) is communicated with the water storage tank (8) through a drain pipe II (404), a water distributor (5) is arranged in the water distribution tank (4), the water distributor (5) comprises a water distribution plate (501) which is horizontally arranged, the water distribution plate (501) divides the interior of the water distribution tank (4) into an upper chamber (406) and a lower chamber (407), a plurality of water distribution holes (502) which are communicated with the upper chamber (406) and the lower chamber (407) and used for water guiding are distributed on the water distribution plate (501), the section of each water distribution hole (502) is in a hyperbolic shape, a gas collection cover (503) which surrounds the water distribution hole (502) and is in an inverted frustum shape is arranged at the bottom of each water distribution hole (502), the gas collection cover (503) is matched with the lower part of the water distribution hole (502) to form a gas gathering cavity (504), a gas injection assembly (6) is arranged in the gas gathering cavity (504), and the gas injection assembly (6) comprises a first gas injection disc (601) and a second disc (601) arranged on the 607) The first air jet disc (601) shields an opening (505) at the bottom of the air gathering cavity (504), a gap is reserved between the first air jet disc and the air gathering cavity, a plurality of first air jet holes (602) which are inclined upwards are arranged on the surface surrounding the first air jet disc (601), so that steam sprayed by the first air jet holes (602) is obliquely and upwards sprayed to the surface of the air collecting hood (503), and is collided and converged at the center of the top of the air gathering cavity (504) after being rebounded by the surface of the air collecting hood (503) and the inner wall at the bottom of the water distribution holes (502) in sequence to form semi-annular steam flow which is upwards along the water distribution holes (502), and thus deoxygenated water entering the water distribution holes (502) is heated for one time;

the first air injection holes (602) in the first air injection disc (601) are supplied with water vapor through a first steam inlet pipe (603), the first steam inlet pipe (603) is communicated with a steam outlet of a conical second heat exchange coil (7), the second heat exchange coil (7) is also a conical coil which is formed by spirally arranging hollow copper pipes and has the diameter of the bottom larger than that of the top, a spiral second spiral line (701) is formed between the hollow copper pipes on the surface of the conical coil, and the top of the second heat exchange coil (7) is positioned in an opening (505) at the bottom of the air gathering cavity (504), so that deoxygenated water entering the water distribution hole (502) falls onto the surface of the second heat exchange coil (7) through the opening (505) and performs secondary heat exchange with steam in the second heat exchange coil (7) in the downward flowing process along the outer wall of the second heat exchange coil (7); a first steam injection pipe (702) for feeding steam into the second heat exchange coil (7) is arranged at the bottom of the second heat exchange coil;

the second air injection disc (607) is a conical part extending into the narrow part in the middle of the water distribution hole (502), and second air injection holes (6010) inclining upwards are distributed around the second air injection disc (607) so that steam sprayed from the second air injection holes (6010) is obliquely blown to the inner wall in the middle of the water distribution hole (502) to form an air seal to the gas gathering cavity (504), and simultaneously, a low-pressure area is formed in the narrow part in the middle of the water distribution hole (502) to promote the steam in the gas gathering cavity (504) to be sprayed upwards along the water distribution hole (502) so as to contact with deoxygenated water in the water distribution hole (502) for heating; the second gas injection hole (6010) is injected with the steam from the second steam injection pipe (608).

4. The system for secondarily deoxidizing water for boilers by using high-temperature flue gas as claimed in claim 3, wherein: a row of second steam branch pipes (402) uniformly supplied with steam by a first steam main pipe are arranged in a lower chamber (407) of the water distribution box (4), a first steam branch pipe (403) is arranged below a gap between every two adjacent second steam branch pipes (402), and all the first steam branch pipes (403) are uniformly supplied with steam by the second steam main pipe; the water distribution holes (502) on the water distribution plate (501) are uniformly distributed in rows, and each water distribution hole (502) corresponds to one second steam branch pipe (402) and one first steam branch pipe (403), so that a first steam injection pipe (702) below any one water distribution hole (502) in the row is communicated with the first steam branch pipe (403), and a second steam injection pipe (608) is communicated with the second steam branch pipe (402); the first steam injection pipe (702) and the second steam injection pipe (608) form a third deoxygenated water heat exchange area, and the second steam branch pipe (402) and the first steam branch pipe (403) form a fourth deoxygenated water heat exchange area.

5. The system for secondarily deoxidizing water for boilers by using high-temperature flue gas as claimed in claim 3, wherein: the water distribution holes (502) comprise an outer expanded water facing area (5021) at the upper part, a narrow area (5022) at the middle part and an outer diffused water area (5023) at the bottom, so that deoxygenated water is blown from the bottom to the top by steam when passing through the narrow area (5022), and is dispersed downwards by adhering to the side wall of the outer diffused water area (5023), and the heating efficiency is improved.

6. The system for secondarily deoxidizing water for boilers by using high-temperature flue gas as claimed in claim 3, wherein: a third air injection disc (604) is fixed on the connecting rod (606), and third air injection holes (605) are obliquely arranged on the side surface surrounding the third air injection disc (604), so that steam sprayed out of the third air injection holes (605) obliquely impacts the inner wall of the lower part of the water distribution hole (502) and then rebounds upwards; the third gas injection holes (605) are also injected with steam by the second steam injection pipe (608);

the center of the conical bottom of the second jet disc (607) is provided with a conical concave pit (609) so as to form an annular fin at the bottom of the second jet disc (607); a contact point of steam ejected by a third air ejecting hole (605) on a third air ejecting disc (604) and the lower side wall of a water distribution hole (502) is defined as a steam inflection point, a tangential direction at the steam inflection point is defined as a reference line, a connecting line of the third air ejecting hole (605) and the steam inflection point is defined as a ray A, a connecting line of a vertex of a conical pit (609) and the steam inflection point is defined as a ray B, an included angle between the ray A and the reference line is an acute angle and is larger than an included angle between the ray B and the reference line, and meanwhile, an included angle between the ray B and a vertical direction is smaller than an included angle between the side wall of the conical pit (609) and the vertical direction, so that after steam flow ejected by the third air ejecting hole (605) rebounds against the lower inner wall of the water distribution hole (502), a part of steam flow can form a circulating flow in a gas gathering cavity (.

7. The system for secondarily deoxidizing water for boilers by using high-temperature flue gas as claimed in claim 3, wherein: the second heat exchange coil (7) is arranged on a metal mesh plate (405), the metal mesh plate (405) is a metal plate with the edge fixed on the inner wall of the water distribution tank (4), and a reticular plate structure formed by water permeable holes penetrating through the metal plate in the thickness direction is densely distributed on the metal plate.

8. The system for secondarily deoxidizing water for boilers by using high-temperature flue gas as claimed in claim 3, wherein: the conical top of the second air injection disc (607) is connected with 1-4 deflector rods (6011), the bottom of each deflector rod (6011) is hinged to the top of the second air injection disc (607), the top end of each deflector rod extends to the upper part of the corresponding water distribution hole (502) and leans against the middle of the corresponding water distribution hole (502) in an inclined mode, stirring is carried out under the blowing of water vapor, and a water film blocking the downward flow of the deoxygenated water is prevented from being generated in the middle of the corresponding water distribution hole (502) by the deoxygenated water.

Images