CN209752547U - Raw flue gas sensible heat deep utilization regeneration system - Google Patents

Abstract

The utility model discloses a regeneration system is utilized to former flue gas sensible heat degree of depth. The regeneration system is characterized in that a liquid storage unit is arranged in an absorption device, an inner cavity is divided into a first smoke treatment area and a second smoke treatment area by using the liquid storage unit, smoke enters from the bottom of the absorption device and is in countercurrent contact with a concentrated solution sprayed on the top of the absorption device, the concentrated solution in the second smoke treatment area absorbs the moisture in the smoke to become dilute, latent heat released in the phase change process of the moisture is separated out, and the smoke and the concentrated solution are heated to 55-65 ℃; the heated concentrated solution is led out through the liquid storage unit to enter the first heat exchanger to exchange heat with a heat exchange medium (such as heat supply network water), the heat exchange medium can be heated to 3-10 ℃, the concentrated solution enters the first flue gas treatment area after being cooled to be approximately consistent with the temperature of the solution inlet at the top of the second flue gas treatment area, the water in the flue gas is continuously absorbed, the first step heat exchange is adopted, the heat exchange quality can be effectively improved, and the sensible heat of the original flue gas and the latent heat of the purified flue gas steam are deeply recovered and utilized.

Description

Raw flue gas sensible heat deep utilization regeneration system

Technical Field

The utility model belongs to the technical field of the environmental protection, concretely relates to regeneration system is utilized to former flue gas sensible heat degree of depth.

background

At present, the mainstream smoke plume elimination technology is that a flue gas condenser and a spray tower are arranged behind a desulfurizing tower or a slurry cooler is added on a slurry circulating slurry pipe to cool flue gas at the outlet of the desulfurizing tower to separate out moisture, and the flue gas is heated by using the waste heat of the original flue gas.

Meanwhile, the flue gas condensation and water separation require external refrigerants, so that great energy waste is caused. The cold source is a problem which must be faced by the current mainstream technology in order to take away latent heat of purified flue gas, particularly for areas which stipulate the outlet flue gas temperature and moisture content of a desulfurizing tower, the cold source needs to be condensed in winter or even needs to be condensed in summer, and a water cooling tower in a power plant is always operated at full load in summer, so that an effective cold source cannot be provided, if investment is required to be increased for newly-built water cooling towers, waste water is replaced by good water, and a water-saving effect cannot be achieved. If the new mechanical ventilation cooling tower is built, the construction cost is extremely high, and the new mechanical ventilation cooling tower cannot bear a power plant.

SUMMERY OF THE UTILITY MODEL

Therefore, the to-be-solved technical problem of the utility model is that there is a large amount of latent heats of the sensible heat of unable degree of depth utilization original flue gas and water vapor in the clean flue gas in the current technical route of retrieving the flue gas waste heat, and energy and water waste, investment cost are big simultaneously, eliminate colored cigarette feather and only invest in the defect that does not have the income to an original flue gas sensible heat degree of depth utilizes regeneration system has been provided.

Therefore, the technical proposal adopted by the application is that,

a deep utilization and regeneration system of sensible heat of raw flue gas, which comprises a dust removal device, a desulfurization device and an absorption device which are sequentially communicated and arranged, and also comprises a flue gas regeneration device,

The liquid storage unit is arranged in the absorption device and divides the inner cavity of the absorption device into a first smoke treatment area and a second smoke treatment area, and smoke is suitable to enter the second smoke treatment area from the first smoke treatment area through the liquid storage unit;

The liquid inlet end of the first heat exchanger is communicated with the liquid storage unit, and the liquid outlet end of the first heat exchanger is communicated with the first flue gas treatment area close to the liquid storage unit, so that the solution in the liquid storage unit enters the first heat exchanger for heat exchange, and the solution after heat exchange is sent to the first flue gas treatment area to be contacted with flue gas;

the coal economizer is arranged between the dust removal device and the desulfurization device;

And the eighth heat exchanger is arranged between the lower part of the absorption device and the economizer and is respectively connected with the lower part of the absorption device and the economizer so as to send the solution in the first flue gas treatment area into the eighth heat exchanger to exchange heat with a heat exchange medium, and send the heat exchange medium after heat exchange into the economizer to exchange heat with the flue gas passing through the economizer.

the flue gas absorption device further comprises a first packing layer and a second packing layer, wherein the first packing layer is arranged in the absorption device between the first spraying unit and the liquid storage unit, and the second packing layer is arranged in the absorption device between the second spraying unit and the flue gas inlet.

Further, a regeneration system is also included, the regeneration system including,

the upper part of the flash tank is provided with a dilute solution inlet and a steam outlet respectively, and the lower part of the flash tank is provided with a concentrated solution outlet;

And the lower part of the absorption device, the sixth heat exchanger and the dilute solution inlet are communicated in sequence.

The concentrated solution outlet, the fifth heat exchanger and the first spraying unit are sequentially communicated and arranged so as to spray the concentrated solution after heat exchange on the rising flue gas through the first spraying unit;

And the second spraying unit is arranged in the absorption device close to and below the liquid storage unit, and the liquid storage unit, the first heat exchanger and the second spraying unit are sequentially communicated so as to spray the solution contacted with the flue gas onto the clean flue gas after heat exchange and realize counter-current convection with the clean flue gas.

Further, the liquid storage unit, the first heat exchanger and the second spraying unit are communicated in sequence, so that the solution in the liquid storage unit is sent to the second spraying unit after heat exchange;

the lower part of the absorption device, the fifth heat exchanger, the sixth heat exchanger and the dilute solution inlet are communicated in sequence, so that heat exchange is carried out between the fifth heat exchanger and the concentrated solution from the concentrated solution outlet of the flash tank, and the concentrated solution is sent to the flash tank after heat exchange is carried out through the sixth heat exchanger.

the lower part of the absorption device, the second heat exchanger and the second spraying unit are sequentially communicated, so that the dilute solution is subjected to heat exchange and then is sent to the second spraying unit;

The lower part of the absorption device, the solution filtering and conditioning system, the second heat exchanger and the second spraying unit are sequentially communicated and arranged so as to send the dilute solution into the second spraying unit after the dilute solution is subjected to filtering, conditioning and heat exchange.

The heat exchanger comprises a first heat exchanger, a second heat exchanger, a third heat exchanger and a fourth heat exchanger which are sequentially communicated, so that incoming water or low-condensation water of a heat supply network sequentially passes through the first heat exchanger, the second heat exchanger, the third heat exchanger and the fourth heat exchanger and exchanges heat with substances entering the corresponding heat exchangers; or the like, or, alternatively,

The first heat exchanger, the second heat exchanger, the fourth heat exchanger and the third heat exchanger are communicated in sequence, so that incoming water or low-condensation water of a heat supply network sequentially passes through the first heat exchanger, the second heat exchanger, the fourth heat exchanger and the third heat exchanger and exchanges heat with substances entering the corresponding heat exchangers.

further, the sixth heat exchanger is communicated with the third heat exchanger, so that the extracted air condensate water of the sixth heat exchanger is sent to the third heat exchanger for heat exchange and then returned to the boiler for water supply; the steam outlet is communicated with the fourth heat exchanger so as to send secondary steam into the fourth heat exchanger for heat exchange, and the secondary steam is used as process make-up water after the heat exchange; or the like, or, alternatively,

The sixth heat exchanger is communicated with the fourth heat exchanger, so that the extracted condensed water of the sixth heat exchanger is sent to the fourth heat exchanger for heat exchange and then returned to the boiler for water supply; and the steam outlet is communicated with the third heat exchanger so as to send secondary steam into the third heat exchanger for heat exchange, and the secondary steam is used as process make-up water after the heat exchange.

Furthermore, the lower part of the absorption device is provided with a flue gas inlet, the upper part of the absorption device is provided with a flue gas outlet, the flue gas outlet is communicated with the chimney, and the first spraying unit, the liquid storage unit and the second spraying unit are all positioned between the flue gas inlet and the flue gas outlet;

The demister is arranged in the absorption device and is positioned between the first spraying unit and the flue gas outlet.

further, a first pump is arranged between the lower part of the absorption device and the second heat exchanger or between the second heat exchanger and the second spraying unit;

A second pump is arranged between the lower part of the absorption device and the solution filtering tempering system, or between the solution filtering tempering system and the second heat exchanger, or between the second heat exchanger and the second spraying unit;

a third pump is arranged between the lower part of the absorption device and the fifth heat exchanger, or between the fifth heat exchanger and the sixth heat exchanger, or between the sixth heat exchanger and the flash tank;

And a fourth pump is arranged between the concentrated solution outlet and the fifth heat exchanger or between the fifth heat exchanger and the first spraying unit.

The utility model discloses technical scheme has following advantage:

1. The utility model provides a regeneration system is utilized to former flue gas sensible heat degree of depth sets up the liquid unit of storing in absorbing device, utilizes it to divide into first flue gas treatment area and second flue gas treatment area with the inner chamber, and the flue gas gets into from absorbing device's bottom and the concentrated solution (like strong brine solution) that the absorbing device top sprayed contact against the current, and the concentrated solution in second flue gas treatment area absorbs the moisture in the flue gas and becomes rare, separates out the latent heat of release among the moisture phase transition process, heats flue gas and concentrated solution to 55 ℃ -65 ℃; the heated concentrated solution is led out through the liquid storage unit to enter the first heat exchanger to exchange heat with a heat exchange medium (such as heat supply network water), the heat exchange medium can be heated to 3-10 ℃, the concentrated solution enters the first flue gas treatment area after being cooled to be approximately consistent with the temperature of the solution inlet at the top of the second flue gas treatment area, the water in the flue gas is continuously absorbed, the cascade heat exchange is adopted for the first time, and the heat exchange quality can be effectively improved. Meanwhile, an economizer is arranged between the dust removal device and the desulfurization device, the lower part of the absorption device is connected with the economizer so as to send the solution in the first flue gas treatment area into the economizer, an eighth heat exchanger is arranged between the lower part of the absorption device and the economizer so as to fully recover the sensible heat of the flue gas, finally the sensible heat of the original flue gas and the latent heat of the purified flue gas steam are deeply recovered and utilized by the means, the problem that a large amount of cold sources are needed for cooling and condensing the flue gas in the prior art is avoided, and water resources are greatly saved. Meanwhile, the water in the clean flue gas is recovered, the system operation cost is reduced, the problems that colored smoke plumes are eliminated in a coal-fired power plant or other industries, and a deep water lifting system is only put into use and does not have income are solved, the environment-friendly effects of high efficiency, energy conservation, emission reduction and the like are achieved, and the method has good social and economic influences.

2. the utility model provides a raw flue gas sensible heat degree of depth utilizes regeneration system, utilizes absorbing device to reduce the moisture content of clean flue gas by a wide margin at first, and steam is because phase transition release latent heat in the concentrated solution absorption process, makes the quality and the temperature of clean flue gas improve, can reach the effect of eliminating colored smoke plume, degree of depth lift water, reducing the dust content of clean flue gas and retrieving the low-quality latent heat of water vapor in the clean flue gas simultaneously; then the concentrated solution after absorbing the water vapor in the absorption device is changed into a dilute solution, one part of the dilute solution is cooled through a fifth heat exchanger, and then is recovered to the original concentration through a regeneration system, and finally returns to the second flue gas treatment area; the other part of the flue gas is heated by a heat exchange medium (such as heat supply network water) through a second heat exchanger and then returns to the first flue gas treatment area, the flow rates of the two parts of the flue gas are adjusted according to specific requirements, and the water absorption capacity of the concentrated solution with unit mass can be changed by adjusting the flow rate ratio of the two parts of the flue gas; in addition, the dilute solution sent to the regeneration system is regenerated into a concentrated solution after being treated by the third heat exchanger and the flash tower, and then is conveyed to the absorption device, secondary steam generated by the flash tower enters the fourth heat exchanger to exchange heat with heat supply network water, the heat supply network water is lifted to 85-90 ℃ for heating or low addition of condensed water, and the cooled condensed water can be used as washing water of a demister of a desulfurization device or as process make-up water and the like, so that the cost and the energy consumption are reduced. Avoids the regenerative use of the steam of the power plant, and can effectively reduce the steam consumption.

3. the utility model provides a regeneration system is utilized to former flue gas sensible heat degree of depth, regeneration system heating season adopt the steam turbine to bleed and take out steam, and the comdenstion water of bleeding is after third heat exchanger or fourth heat exchanger heat transfer, and the boiler feed water returns. After heat exchange and temperature rise of heat supply network water or low-condensed water are carried out through a first heat exchanger and a second heat exchanger of an absorption device, heat exchange is carried out with a third heat exchanger and a fourth heat exchanger of a regeneration system, the requirement of the temperature of the heat supply network water is met in a heating season, and the heat supply network returns to the heating season; the low-temperature economizer is used for heating low-temperature condensed water in non-heating seasons or the low-temperature economizer is used for removing low-temperature condensed water after heat exchange, so that the generating capacity of the unit is basically not influenced in the non-heating seasons. The problems that a coal-fired power plant or other industries eliminate wet smoke plume and a deep water lifting system is only put into use and does not have income are solved through the above modes, sensible heat of original flue gas and latent heat of purified flue gas steam after a desulfurization device are further recovered through the coal economizer, the eighth heat exchanger, the fifth heat exchanger, the sixth heat exchanger and the flash tank, water in the purified flue gas is recovered, the operating cost of the system is reduced, and the environment-friendly effects of high efficiency, energy conservation, emission reduction and the like are achieved.

4. The utility model provides a regeneration system is utilized to former flue gas sensible heat degree of depth not only can be used for heating the heat supply network water or lowly adding the condensation water with former flue gas sensible heat, can also retrieve a large amount of latent heats of vapor in the flue gas simultaneously, and the flue gas waste heat is retrieved to the degree of depth, because retrieve latent heat in-process flue gas temperature and rise simultaneously, can reduce the flue gas moisture content simultaneously and improve the flue gas temperature, reaches and retrieves latent heat and eliminate colored smoke feather in coordination and reduce the effect of flue gas dust content. The device recovers water saving resources through deep water lifting, and compared with the prior art, the device can reduce the operating pressure drop of the system by more than one third due to simple system equipment, saves operating cost and has good environment-friendly and energy-saving effects.

drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the technical solutions in the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a layout diagram of a raw flue gas sensible heat deep utilization regeneration system in an embodiment of the present invention;

FIG. 2 is a system diagram of a raw flue gas sensible heat deep utilization regeneration system in an embodiment of the present invention;

FIG. 3 is a schematic structural view of an embodiment of the absorption device of the present invention;

Wherein the reference numerals are represented as:

1-a dust removal device; 2-a desulfurization unit; 3-an absorption device; 3-1-a first spraying unit; 3-2-a second spraying unit; 3-3-a reservoir unit; 3-4-a flue gas inlet; 3-5-a flue gas outlet; 3-6-a demister; 4-a coal economizer; 5-a first pump; 6-a second pump; 7-solution filtration conditioning system; 8-a first heat exchanger; 9-a second heat exchanger; 10-a third heat exchanger; 11-a fourth heat exchanger; 12-a third pump; 13-a fifth heat exchanger; 14-a fourth pump; 15-an eighth heat exchanger; 16-heat supply network incoming water or low condensed water; 17-a sixth heat exchanger; 18-a flash tank; 19-a chimney; 20-a seventh heat exchanger; 21-solution replenishing tank; 22-fifth pump.

Detailed Description

The technical solutions of the present invention will be described clearly and completely below, and it should be apparent that the described embodiments are some, but not all embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

in the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", 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 simplification of description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

in the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

furthermore, the technical features mentioned in the different embodiments of the invention described below can be combined with each other as long as they do not conflict with each other.

Example 1

the embodiment provides a raw flue gas sensible heat deep utilization regeneration system, as shown in fig. 1 and 2, which comprises a dust removal device 1, a desulfurization device 2 and an absorption device 3 which are sequentially communicated, for example, the dust removal device 1 can be an electric dust remover, the desulfurization device 2 can be a desulfurization tower, the absorption device 3 can be an absorption tower, more specifically, a spray tower or a packed tower, the lower part of the absorption device 3 is provided with a flue gas inlet 3-4, the upper part of the absorption device is provided with a flue gas outlet 3-5, the system further comprises a liquid storage unit 3-3, for example, the liquid storage unit 3-3 can be a liquid receiving disc, as shown in fig. 3, the liquid receiving disc is provided with a disc which is matched with the inner cavity of the desulfurization tower, a through hole is arranged on the disc, the through hole is provided with an extension section which extends towards the top of the desulfurization tower along the axial direction of the desulfurization tower, a liquid storage space is arranged between adjacent extension sections and is arranged in the absorption device 3, the flue gas is suitable for entering a second flue gas treatment area from the first flue gas treatment area through a liquid storage unit 3-3; specifically, the liquid storage unit 3-3 may be disposed in the middle of the desulfurization tower;

the liquid inlet end of the first heat exchanger 8 is communicated with the liquid storage unit 3-3, and the liquid outlet end of the first heat exchanger is communicated with the first flue gas treatment area close to the liquid storage unit 3-3, so that the solution in the liquid storage unit 3-3 enters the first heat exchanger 8 for heat exchange, and the solution after heat exchange is sent to the first flue gas treatment area to be contacted with flue gas;

the economizer 4 is arranged between the dust removal device 1 and the desulfurization device 2; specifically, the economizer 4 may be a low-temperature economizer, and the temperature of the flue gas is reduced to about 90 ℃ by using heat medium circulating water by using the low-temperature economizer, and the absorbed heat heats the dilute solution by using the heat medium circulating water;

The eighth heat exchanger 15 is arranged between the lower part of the absorption device 3 and the economizer 4 and is respectively connected with the lower part of the absorption device 3 and the economizer 4 so as to send the solution in the first flue gas treatment area into the eighth heat exchanger 15 to exchange heat with a heat exchange medium, and send the heat exchange medium after heat exchange into the economizer 4 to exchange heat with the flue gas passing through the economizer 4; specifically, eighth heat exchanger 15 is plate heat exchanger, and the heat transfer medium can be heat medium circulating water, adopts low temperature economizer and eighth heat exchanger 15 to heat dilute solution, can avoid the flue gas dividing wall formula direct heating dilute solution heat exchanger material that causes to improve the problem, reduces investment cost.

In the original flue gas sensible heat deep utilization regeneration system, a liquid storage unit 3-3 is arranged in an absorption device 3, an inner cavity is divided into a first flue gas treatment area and a second flue gas treatment area by the liquid storage unit, flue gas enters from the bottom of the absorption device 3 and is in countercurrent contact with concentrated solution (such as concentrated salt solution) sprayed on the top of the absorption device 3, the concentrated solution in the second flue gas treatment area absorbs the moisture in the flue gas to be diluted, latent heat released in the phase change process of the moisture is separated out, and the flue gas and the concentrated solution are heated to 55-65 ℃; the heated concentrated solution is led out through the liquid storage unit 3-3 to enter the first heat exchanger to exchange heat with a heat exchange medium (such as heat supply network water), the heat exchange medium can be heated to 3-10 ℃, the concentrated solution enters the first flue gas treatment area after being cooled to be approximately consistent with the temperature of the solution inlet at the top of the second flue gas treatment area, the water in the flue gas is continuously absorbed, the cascade heat exchange is adopted for the first time, and the heat exchange quality can be effectively improved. Meanwhile, an economizer is arranged between the dust removal device and the desulfurization device, the lower part of the absorption device is connected with the economizer so as to send the solution in the first flue gas treatment area into the economizer, an eighth heat exchanger is arranged between the lower part of the absorption device and the economizer so as to fully recover the sensible heat of the flue gas, finally the sensible heat of the original flue gas and the latent heat of the purified flue gas steam are deeply recovered and utilized by the means, the problem that a large amount of cold sources are needed for cooling and condensing the flue gas in the prior art is avoided, and water resources are greatly saved. Meanwhile, the water in the clean flue gas is recovered, the system operation cost is reduced, the problems that colored smoke plumes are eliminated in a coal-fired power plant or other industries, and a deep water lifting system is only put into use and does not have income are solved, the environment-friendly effects of high efficiency, energy conservation, emission reduction and the like are achieved, and the method has good social and economic influences.

further, the device also comprises a first packing layer and a second packing layer, wherein the first packing layer is arranged in the absorption device 3 between the first spraying unit 3-1 and the liquid storage unit 3-3, and the second packing layer is arranged in the absorption device 3 between the second spraying unit 3-2 and the flue gas inlet 3-4; specifically, the packing in the first packing layer and the second packing layer may be structured packing or random packing.

Further, the system comprises a regeneration system, wherein the regeneration system comprises a flash tank 18, the upper part of the flash tank is respectively provided with a dilute solution inlet and a steam outlet, and the lower part of the flash tank is provided with a concentrated solution outlet; specifically, the middle part is provided with a dilute solution inlet, and the upper part is provided with a steam outlet; the lower part of the absorption device 3, the sixth heat exchanger 17 and the dilute solution inlet are communicated in sequence; in particular, the sixth heat exchanger 17 may be a plate heat exchanger.

in addition, the driving heat source of the regeneration system is used for pumping air for the unit in the heating season, and heat supply network water, circulating heat medium water or low-condensed water is heated to different temperatures through the heat supply network heat exchanger in different seasons.

in this embodiment, the device further comprises a first spraying unit 3-1, which is arranged in the absorption device 3 near the middle upper part and above the liquid storage unit 3-3, and the concentrated solution outlet, the fifth heat exchanger 13 and the first spraying unit 3-1 are sequentially communicated with each other, so that the concentrated solution after heat exchange is sprayed on the rising flue gas through the first spraying unit 3-1; the second spraying unit 3-2 is arranged in the absorption device 3 and is close to and below the liquid storage unit 3-3, and the liquid storage unit 3-3, the first heat exchanger 8 and the second spraying unit 3-2 are communicated in sequence so as to spray the solution contacted with the flue gas on the clean flue gas after heat exchange so as to perform counter-current flow with the clean flue gas; specifically, the first spraying unit 3-1 and the second spraying unit 3-2 both comprise spraying conduits and spraying nozzles arranged on the spraying conduits at intervals, and the first spraying unit 3-1 and the second spraying unit 3-2 are both close to and below the flue gas outlet 3-5 of the absorption device 3, so that the countercurrent contact path is prolonged, and the heat in the flue gas can be effectively recovered.

Specifically, the liquid storage unit 3-3, the first heat exchanger 8 and the second spraying unit 3-2 are communicated in sequence, so that the solution in the liquid storage unit 3-3 is sent to the second spraying unit after heat exchange;

The lower part of the absorption device 3, the fifth heat exchanger 13, the sixth heat exchanger 17 and the dilute solution inlet are communicated in sequence, so that the solution at the bottom of the absorption tower exchanges heat with the concentrated solution from the concentrated solution outlet of the flash tank in the fifth heat exchanger 13, exchanges heat with the concentrated solution through the sixth heat exchanger 17, and is finally sent to the flash tank 18; the fifth heat exchanger 13 may be a plate heat exchanger;

In addition, a seventh heat exchanger 20 is also arranged, and the concentrated solution from the fifth heat exchanger 13 can enter the seventh heat exchanger 20 to exchange heat with heat supply network water or low-pressure condensate water and then enter the absorption device 3.

Example 2

The embodiment provides a raw flue gas sensible heat deep utilization regeneration system, on the basis of the embodiment 1, in order to improve the heat exchange effect, fully recover the sensible heat in the raw flue gas and the latent heat of purified flue gas steam, and fully regenerate the waste liquid, the system further comprises a second heat exchanger 9, wherein the lower part of the absorption device 3, the second heat exchanger 9 and a second spraying unit 3-2 are sequentially communicated and arranged, so that a dilute solution is sent to the second spraying unit 3-2 after heat exchange; meanwhile, in order to filter and modulate the concentrated solution serving as the absorption liquid in the absorption device, the absorption device further comprises a solution filtering and conditioning system 7, the lower part of the absorption device 3, the solution filtering and conditioning system 7, a second heat exchanger 9 and a second spraying unit 3-2 are sequentially communicated, so that the dilute solution is sent to the second spraying unit 3-2 after being subjected to filtering, conditioning and heat exchange; specifically, as shown in fig. 2, the solution filtration and conditioning system 7 is composed of a cyclone + a filter which are communicated in sequence, and a solution replenishing tank 21 and a fifth pump 22 which are communicated in sequence are provided, and the fifth pump 22 is communicated with the solution filtration and conditioning system 7 to replenish the solution therein.

Example 3

The embodiment provides a raw flue gas sensible heat deep utilization regeneration system, which further comprises a third heat exchanger 10 and a fourth heat exchanger 11 on the basis of the embodiment 1 or 2, wherein the first heat exchanger 8, the second heat exchanger 9, the third heat exchanger 10 and the fourth heat exchanger 11 are sequentially communicated, so that heat supply network incoming water or low condensed water sequentially passes through the first heat exchanger 8, the second heat exchanger 9, the third heat exchanger 10 and the fourth heat exchanger 11 and exchanges heat with substances entering the corresponding heat exchangers;

As a variant embodiment, the positions of the third heat exchanger 10 and the fourth heat exchanger 11 can be changed according to the temperature of the primary steam condensate and the temperature of the secondary steam, specifically, the first heat exchanger 8, the second heat exchanger 9, the fourth heat exchanger 11 and the third heat exchanger 10 are sequentially communicated, so that the incoming water or low-condensed water of the heat supply network sequentially passes through the first heat exchanger 8, the second heat exchanger 9, the fourth heat exchanger 11 and the third heat exchanger 10 and exchanges heat with the substances entering the corresponding heat exchangers.

further, the sixth heat exchanger 17 is communicated with the third heat exchanger 10, so that the extracted air condensate water of the sixth heat exchanger 17 is sent to the third heat exchanger 10 for heat exchange and then returned to the boiler for water supply; the steam outlet is communicated with a fourth heat exchanger 11, secondary steam condensate water of a sixth heat exchanger 17 is sent to the fourth heat exchanger 10, and is used as process make-up water after heat exchange, and heat supply network incoming water or low-addition condensate water after passing through a first heat exchanger 8, a second heat exchanger 9, the third heat exchanger 10 and the fourth heat exchanger 11 is used as heat supply network return water or returns to a low-addition system, namely used as heat supply network incoming water or low-addition condensate water 16;

as a modified embodiment, the sixth heat exchanger 17 is communicated with the fourth heat exchanger 11, so that the extracted air condensate of the sixth heat exchanger 17 is sent to the fourth heat exchanger 11 for heat exchange, and then is returned to the boiler for water supply; the steam outlet is communicated with the third heat exchanger 10 so as to send the secondary steam condensate water of the sixth heat exchanger 17 into the third heat exchanger 10, after heat exchange, the secondary steam condensate water is used as process make-up water, and the heat supply network incoming water or low-addition condensate water passing through the first heat exchanger 8, the second heat exchanger 9, the third heat exchanger 10 and the fourth heat exchanger 11 is used as heat supply network return water or a low-addition system, namely used as heat supply network incoming water or low-addition condensate water 16;

in order to realize the flow of liquid, a first pump 5 is arranged between the lower part of the absorption device 3 and the second heat exchanger 9 or between the second heat exchanger 9 and the second spraying unit 3-2; a second pump 6 is arranged between the lower part of the absorption device 3 and the solution filtering and tempering system 7, or between the solution filtering and tempering system 7 and the second heat exchanger 9, or between the second heat exchanger 9 and the second spraying unit 3-2; a third pump 12 is arranged between the lower part of the absorption device 3 and the fifth heat exchanger 13, or between the fifth heat exchanger 13 and the sixth heat exchanger 17, or between the sixth heat exchanger 17 and the flash tank 17; and a fourth pump 14 is arranged between the concentrated solution outlet and the fifth heat exchanger 13 or between the fifth heat exchanger 13 and the first spraying unit 3-1.

in addition, the secondary steam at the top of the flash tank 18 enters the third heat exchanger 10 or the fourth heat exchanger 11 to raise the heat supply network water to 85-90 ℃ for heating or low condensed water addition.

Example 4

The embodiment provides a deep utilization and regeneration system of sensible heat of raw flue gas, on the basis of the embodiments 1, 2 or 3, the lower part of an absorption device 3 is provided with a flue gas inlet 3-4, the upper part is provided with a flue gas outlet 3-5, the flue gas outlet 3-5 is communicated with a chimney 19, and a first spraying unit 3-1, a liquid storage unit 3-3 and a second spraying unit 3-2 are all positioned between the flue gas inlet 3-4 and the flue gas outlet 3-5; the demister 3-6 is arranged in the absorption device 3 and is positioned between the first spraying unit 3-1 and the flue gas outlet 3-5.

If the smoke temperature needs to be raised to a higher temperature, a reheating heat exchanger can be arranged on a flue behind a smoke outlet 3-4 of the absorption device 3 or a heat exchange pipe is arranged in the top of the upper section of the absorption device 3, so that the smoke temperature can be heated to the temperature required by environmental protection or owners.

In addition, the specific working principle of the above device is as follows:

as shown in figures 1 and 2, flue gas enters from the bottom of the absorption tower and flows counter-currently with the strong salt solution sprayed from the top of the absorption tower, the strong salt solution at the top of the upper section of the absorption tower absorbs the flue gas to dilute, latent heat is released in the phase change process of precipitated moisture, and the flue gas and the salt solution are heated to 55-65 ℃. The heated solution is led out through a liquid receiving disc at the bottom of the upper section to enter a first heat exchanger (a heat supply network primary heat exchanger) to exchange heat with heat supply network water, the heat supply network water can be heated to 3-10 ℃, the saline solution is cooled to be consistent with the inlet temperature of the solution at the top of the upper section and then enters the top of the lower section of the absorption tower to continuously absorb moisture in the flue gas, the dilute solution at the bottom of the lower section of the absorption tower is respectively sent to a second heat exchanger (a heat supply network secondary heat exchanger) and a fifth heat exchanger (a dilute concentrated solution heat exchanger) by a first pump (a dilute saline solution pump), the heat supply network water which is discharged from the first heat exchanger (the heat supply network primary heat exchanger) exchanges heat with the dilute solution which enters the second heat exchanger (the heat supply network secondary heat, mixing the solution with the solution at the outlet of the first heat exchanger (heat supply network first-level heat exchanger), feeding the mixture into the top of the lower section of the absorption tower for spraying, and heating the heat supply network water or low condensed water to 50-60 ℃; the technology considers the temperature gradient from the top to the bottom of the absorber, and the first-stage heat exchanger and the second-stage heat exchanger of the absorber perform cascade heat exchange, so that the quality of hot water can be effectively improved; the dilute solution entering the fifth heat exchanger (dilute-concentrated solution heat exchanger) exchanges heat with the concentrated solution from the regeneration system and then enters the regeneration system.

and the lower-section absorption liquid of part of the absorber is sent to an eighth heat exchanger 15 (a plate type intermediate heat exchanger) to exchange heat with the heat medium water from the economizer 4, the heat exchange liquid is mixed with the dilute solution heated by the concentrated solution, the heat medium water is heated by utilizing the sensible heat of the raw flue gas, the absorption liquid heated by the heat medium water enters a sixth heat exchanger (a steam heater) to be continuously heated to 120-140 ℃ (the heat source adopts steam of a pump set), and then flash evaporation is carried out by a flash tank. The flue heat exchanger adopts a low-temperature economizer, the temperature of the flue gas is reduced to about 90 ℃ by using heat medium circulating water, and the absorbed heat heats the dilute solution through the heat medium circulating water. The extracted condensed water enters a third heat exchanger (a heat supply network third-level heat exchanger) or a fourth heat exchanger (a heat supply network fourth-level heat exchanger) to exchange heat with the heat supply network water, the secondary steam at the top of the flash tank enters the fourth heat exchanger (a heat supply network fourth-level heater) or the third heat exchanger (a heat supply network third-level heat exchanger) to lift the heat supply network water or low condensed water to about 95 ℃, the concentrated solution at the bottom of the flash tank exchanges heat with the dilute solution in a fifth heat exchanger (a dilute concentrated solution heat exchanger), and the concentrated solution is cooled to 30-50 ℃ by a seventh heat exchanger (a concentrated solution cooling heat exchanger) and then returns to the top of the upper section of the.

In addition, the temperature of the flue gas outlet of the low-temperature economizer is generally required to be not lower than 90 ℃, the temperature of the flue gas can be reduced to 90 ℃ through circulating heat medium water, so that the original temperature of the flue gas at the inlet of the desulfurizing tower can be fully absorbed, the evaporation water quantity of the desulfurizing tower can be reduced, and the process water supplement quantity of the desulfurizing tower can be reduced. In order to prevent low-temperature corrosion, the outlet water temperature of low-temperature heating medium water is generally above 70 ℃, the temperature of dilute solution discharged from the bottom of an absorber is about 70 ℃, the heat of original flue gas can be fully recovered by utilizing the small heat exchange temperature end difference of a plate heat exchanger, the heat of the original flue gas can be basically and completely recovered when the temperature of the original flue gas is 140 ℃, the steam quantity of a regeneration system can be reduced by utilizing the sensible heat of the original flue gas, regeneration can be realized in non-heating seasons even without using steam, when the sensible heat of the flue gas can not completely meet the heat of regeneration, the dilute solution is sent into a steam heater to be continuously heated (the heat source adopts steam of a pump set), and. The extracted condensed water enters a heat supply network third-level heat exchanger to exchange heat with heat supply network water, and secondary steam at the top of the flash evaporation tank enters a heat supply network fourth-level heater to raise the temperature of the heat supply network water to 85-90 ℃ for heating or adding the condensed water to a low level. The concentrated solution at the bottom of the flash tank exchanges heat with the dilute solution in the dilute concentrated solution heat exchanger and then returns to the top of the absorption tower.

Specifically, the solution at the bottom of the lower section of the desulfurization tower is divided into four parts:

the first part exchanges heat with the heat supply network secondary heat exchanger and then returns to the top of the lower section of the absorption tower to form a small circulation. The second part is sent to a dilute-concentrated solution heat exchanger for heating and then enters a regeneration system. The third part enters a solution filtering and tempering unit, and the filtering and tempering unit is matched with the bottom of the lower section of the absorption tower, so that on one hand, solid particles accumulated in the absorption tower by the solution and substances such as generated crystal salt (sulfate, carbonate and the like) can be removed through a cyclone and a filtering device, and pollutants and impurities in the solution in the absorption tower can be controlled to a certain degree; on the other hand, the calcium-based salt is added to adjust the pH value of the solution, maintain the absorption capacity of the solution and reduce the corrosivity of the solution. And the fourth part enters the economizer to exchange heat with the flue gas.

the absorption liquid enters from the top of the absorption tower, and through the reverse convection of the uniform spraying or dripping and the clean flue gas entering from the bottom of the absorption tower, the water vapor in the clean flue gas of the packing layer is absorbed by the concentrated solution, and the respective spraying layer or dripping layer of the upper section and the lower section can be provided with a standby layer so as to improve the reliability of the absorption tower. The water absorption capacity of the saline solution of unit mass can be controlled by adjusting the small circulation solution amount of the lower section of the absorption tower, the absorption tower is arranged behind the desulfurization tower, most of water absorption occurs at the part due to high flue gas moisture content at the bottom of the absorption tower, the small circulation is arranged at the bottom of the absorption tower, the balance temperature of the lower section of the absorption tower is controlled by reducing the temperature of the small circulation solution, so that the water absorption capacity of the solution of unit mass is improved, the concentration of the absorbed dilute solution is reduced by 1-10% relative to that of the concentrated solution, and the ratio of the small circulation amount to the regeneration circulation amount can be 1: 1. The desulfurizing tower in the original system does not need to be modified, and the utility model is suitable for a desulfurizing tower system includes single tower double circulation and two tower double circulation systems.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications can be made without departing from the scope of the invention.

Claims (10)

1. A deep utilization and regeneration system of sensible heat of raw flue gas, which comprises a dust removal device, a desulfurization device and an absorption device which are sequentially communicated, and is characterized by also comprising,

the liquid storage unit is arranged in the absorption device and divides the inner cavity of the absorption device into a first smoke treatment area and a second smoke treatment area, and smoke is suitable to enter the second smoke treatment area from the first smoke treatment area through the liquid storage unit;

The liquid inlet end of the first heat exchanger is communicated with the liquid storage unit, and the liquid outlet end of the first heat exchanger is communicated with the first flue gas treatment area close to the liquid storage unit, so that the solution in the liquid storage unit enters the first heat exchanger for heat exchange, and the solution after heat exchange is sent to the first flue gas treatment area to be contacted with flue gas;

the coal economizer is arranged between the dust removal device and the desulfurization device;

And the eighth heat exchanger is arranged between the lower part of the absorption device and the economizer and is respectively connected with the lower part of the absorption device and the economizer so as to send the solution in the first flue gas treatment area into the eighth heat exchanger to exchange heat with a heat exchange medium, and send the heat exchange medium after heat exchange into the economizer to exchange heat with the flue gas passing through the economizer.

2. The raw flue gas sensible heat deep utilization regeneration system of claim 1, further comprising a first packing layer and a second packing layer, wherein the first packing layer is disposed in the absorption device between the first spray unit and the liquid storage unit, and the second packing layer is disposed in the absorption device between the second spray unit and the flue gas inlet.

3. The raw flue gas sensible heat deep utilization regeneration system of claim 2, further comprising a regeneration system, said regeneration system comprising,

the upper part of the flash tank is provided with a dilute solution inlet and a steam outlet respectively, and the lower part of the flash tank is provided with a concentrated solution outlet;

And the lower part of the absorption device, the sixth heat exchanger and the dilute solution inlet are communicated in sequence.

4. The raw flue gas sensible heat deep utilization regeneration system of claim 3, further comprising,

The first spraying unit is arranged in the absorption device close to the middle upper part of the absorption device and positioned above the liquid storage unit, and the concentrated solution outlet, the fifth heat exchanger and the first spraying unit are sequentially communicated so as to spray the concentrated solution after heat exchange on the rising flue gas through the first spraying unit;

And the second spraying unit is arranged in the absorption device close to and below the liquid storage unit, and the liquid storage unit, the first heat exchanger and the second spraying unit are sequentially communicated so as to spray the solution contacted with the flue gas onto the clean flue gas after heat exchange and realize counter-current convection with the clean flue gas.

5. The raw flue gas sensible heat deep utilization regeneration system as claimed in claim 4, wherein the liquid storage unit, the first heat exchanger and the second spraying unit are communicated in sequence, so that the solution in the liquid storage unit is sent to the second spraying unit after heat exchange;

The lower part of the absorption device, the fifth heat exchanger, the sixth heat exchanger and the dilute solution inlet are communicated in sequence, so that heat exchange is carried out between the fifth heat exchanger and the concentrated solution from the concentrated solution outlet of the flash tank, and the concentrated solution is sent to the flash tank after heat exchange is carried out through the sixth heat exchanger.

6. the raw flue gas sensible heat deep utilization regeneration system of claim 5, further comprising,

The lower part of the absorption device, the second heat exchanger and the second spraying unit are sequentially communicated, so that the dilute solution is subjected to heat exchange and then is sent to the second spraying unit;

The lower part of the absorption device, the solution filtering and conditioning system, the second heat exchanger and the second spraying unit are sequentially communicated and arranged so as to send the dilute solution into the second spraying unit after the dilute solution is subjected to filtering, conditioning and heat exchange.

7. The raw flue gas sensible heat deep utilization regeneration system of claim 6, further comprising,

the first heat exchanger, the second heat exchanger, the third heat exchanger and the fourth heat exchanger are communicated in sequence, so that incoming water or low-condensed water of a heat supply network sequentially passes through the first heat exchanger, the second heat exchanger, the third heat exchanger and the fourth heat exchanger and exchanges heat with substances entering the corresponding heat exchangers; or the like, or, alternatively,

The first heat exchanger, the second heat exchanger, the fourth heat exchanger and the third heat exchanger are communicated in sequence, so that incoming water or low-condensation water of a heat supply network sequentially passes through the first heat exchanger, the second heat exchanger, the fourth heat exchanger and the third heat exchanger and exchanges heat with substances entering the corresponding heat exchangers.

8. The raw flue gas sensible heat deep utilization regeneration system of claim 7, wherein the sixth heat exchanger is communicated with the third heat exchanger, so that the extracted air condensate of the sixth heat exchanger is sent to the third heat exchanger for heat exchange and then returned to boiler feed water; the steam outlet is communicated with the fourth heat exchanger so as to send secondary steam into the fourth heat exchanger for heat exchange, and the secondary steam is used as process make-up water after the heat exchange; or the like, or, alternatively,

the sixth heat exchanger is communicated with the fourth heat exchanger, so that the extracted condensed water of the sixth heat exchanger is sent to the fourth heat exchanger for heat exchange and then returned to the boiler for water supply; and the steam outlet is communicated with the third heat exchanger so as to send secondary steam into the third heat exchanger for heat exchange, and the secondary steam is used as process make-up water after the heat exchange.

9. the raw flue gas sensible heat deep utilization regeneration system according to any one of claims 4 to 8, wherein a flue gas inlet is arranged at a lower part of the absorption device, a flue gas outlet is arranged at an upper part of the absorption device, the flue gas outlet is communicated with the chimney, and the first spraying unit, the liquid storage unit and the second spraying unit are all positioned between the flue gas inlet and the flue gas outlet;

The demister is arranged in the absorption device and is positioned between the first spraying unit and the flue gas outlet.

10. The raw flue gas sensible heat depth utilization regeneration system of any one of claims 4 to 8, wherein a first pump is arranged between the lower part of the absorption device and the second heat exchanger, or the second heat exchanger and a second spray unit;

a second pump is arranged between the lower part of the absorption device and the solution filtering tempering system, or between the solution filtering tempering system and the second heat exchanger, or between the second heat exchanger and the second spraying unit;

a third pump is arranged between the lower part of the absorption device and the fifth heat exchanger, or between the fifth heat exchanger and the sixth heat exchanger, or between the sixth heat exchanger and the flash tank;

And a fourth pump is arranged between the concentrated solution outlet and the fifth heat exchanger or between the fifth heat exchanger and the first spraying unit.