CN101995028B - Energy and water saving desulphuration integrated system for power plant - Google Patents
Energy and water saving desulphuration integrated system for power plant Download PDFInfo
- Publication number
- CN101995028B CN101995028B CN2010105279573A CN201010527957A CN101995028B CN 101995028 B CN101995028 B CN 101995028B CN 2010105279573 A CN2010105279573 A CN 2010105279573A CN 201010527957 A CN201010527957 A CN 201010527957A CN 101995028 B CN101995028 B CN 101995028B
- Authority
- CN
- China
- Prior art keywords
- exchanger
- change heat
- level phase
- phase
- mixing chamber
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E20/00—Combustion technologies with mitigation potential
- Y02E20/34—Indirect CO2mitigation, i.e. by acting on non CO2directly related matters of the process, e.g. pre-heating or heat recovery
Landscapes
- Treating Waste Gases (AREA)
- Chimneys And Flues (AREA)
Abstract
The invention discloses an energy and water saving desulphuration integrated system for a power plant in the technical field of heat transmission. The system comprises an I-level phase change heat exchanger, a mixing chamber and a control system, wherein the I-level phase change heat exchanger is arranged on the back of an air preheater arranged on a gas duct at the tail end of a boiler and then is connected with the mixing chamber through a pipeline, the mixing chamber is connected with the air outlet of the air preheater of a boiler system through a pipeline, and the I-level phase change heat exchanger and the mixing chamber are all connected with the control system through connecting wires; or an II-level phase change heat exchanger is arranged between the desulfurization fan and desulfurizing tower of the boiler system. In the invention, the phase change heat exchanger absorbs the energy of raw gas to heat clean air, and the heated clean air is mixed with the low-temperature clean gas after being further heated to a higher temperature by the air preheater, the gas outlet temperature of a chimney is increased, thus the problems of low temperature corrosion of the existing clean gas heater and invalid integral device caused by low temperature corrosion are avoided radically, the low temperature exhaust heat of the raw gas is used fully, the thermal efficiency of the integral electric generating system is improved, and meanwhile, the water resource is saved greatly.
Description
Technical field
What the present invention relates to is the device in a kind of heat transfer technology field, specifically be a kind of be used for that clean flue gas after the wet desulphurization heats up and the power plant of waste heat recovery with energy-saving and water-saving sulphur removal integrated system.
Background technology
Adopting limestone wet-process flue gas desulfurization is the process for sulfur removal that present large power plant generally uses.But; Use the serious cold end corrosion of wet method lime/lime stone desulfurization process (FCD) ubiquity flue gas heat-exchange system; Can't clean flue gas heating is extremely temperature required, and often make that heat transmission equipment is entirely ineffective, finally caused extremely serious secondary pollution problem.In other words, use flue gas heater to improve clean flue-gas temperature, becoming does not for a long time have a fine technical problem that is resolved in the world all the time.Such as according to " heat-engine plant wet flue gas desulfurization technique handbook (China Electric Power Publishing House, 2006), to its main three kinds of form flue gas heaters analysis as follows:
(1) circulation heating (GGH), the heat exchanger of former flue gas through a certain appropriate form that the desulfurizing tower upper reaches is in 130-150 ℃ without desulfurization processing, temperature heats clean flue gas, to promote the final exhaust temperature of flue gas.Only consider that the GGH technology can reasonable distribution or made full use of the energy of flue gas from the angle of energy balance.The GGH of designing proper becomes the preferential best mode of selecting of people naturally,, although the GGH form that is proposed so far is varied, this effort is not succeedd.Trace it to its cause and be: because the dew-point temperature of clean flue gas is usually above the dew-point temperature of former flue gas; Thereby so must be higher than under the precondition that to corrode do not appear in the dew-point temperature of relevant working medium at the wall surface temperature that guarantees heat exchanger; The temperature of former flue gas institute release heat is lower than the temperature that clean flue gas need promote, to such an extent as to can't be realized to the purpose that clean flue gas transmits heat by former flue gas at all.
(2) online heater (SGH) uses by temperature that steam turbine the provided low-pressure steam about 250 ℃ roughly, through the clean flue gas behind the heat exchanger heating desulfurizing tower.This technical scheme once obtained people's generally attention, but did not have real achieving success so far.Reason is to have obviously deficiency: one of which, and it is big that this heat exchanger consumes quantity of steam, and heat loss accounts for 2% of boiler efficiency, and is less economical; They are two years old; This mode does not have to consider how to absorb the entering desulfurizing tower low temperature exhaust heat of former flue gas before fully; To improve the problem of boiler thermal output as far as possible; But also because needing to consume a large amount of cooling waters is used to realize reducing the technological requirement that gets into the former flue-gas temperature of desulfurizing tower, to such an extent as to finally causes the serious waste of water resource and increase the unnecessary thermal pollution of atmospheric environment.Yet the serious cold end corrosion problem that heat exchanger is difficult to overcome causes entire equipment can't continue operate as normal at all.Technically, the tube bank surface temperature is higher, and corrosive environment is expected to relax to some extent.Be higher than 120 ℃ if for example can remain the heating surface temperature, and the flue gas saturation degree is reduced to below 80%, then can obviously reduce the corrosion rate of clean flue gas heat exchanging device.But; Analyse in depth from the mechanism of thermal conduction study; Get into 250 ℃ of inboard low-pressure steams of clean flue gas heater heat exchange pipeline and remain superheated steam, what flow through the heat exchange pipeline outside then is that desulfurizing tower flows out, and temperature is about 50 ℃ and carries the clean flue gas of large quantity of moisture secretly.That is to say that in the SGH heat exchanger, cold fluid and hot fluid roughly is in usually said " gas-gas heat exchange " category.General knowledge according to thermal conduction study can be known; The coefficient of heat transfer in the pipeline outside is far above the coefficient of heat transfer of inboard; Also contain small amount of moisture in the clean flue gas of low temperature in addition and make the coefficient of heat transfer of fume side further strengthen, to such an extent as in the local zone of heat exchanger, it is 50 ℃ the clean flue gas of low temperature that its metallic walls surface temperature extremely approaches temperature; And greatly depart from temperature is 250 ℃ low-pressure steam, can't reach initial at all and expect that wall temperature is higher than 120 ℃ " designing requirement.
(3) direct burning heater through being similar to the optional equipment of gas turbine, utilizes the clean flue gas of the flue gas heating of its generation through desulfurization.Undoubtedly, not only initial investment is excessive, operating cost is too high for this scheme, can't reduce water consumption, but also the very serious secondary thermal pollution problem of association can occur.
Can be known that by above analysis because can not properly settle the cold end corrosion problem, each thermal power plant can only adopt higher exhaust gas temperature, energy dissipation is very big, and still occurs cold end corrosion easily.For addressing the above problem; The applicant proposes another name simultaneously and is called " the composite phase-change heat-exchanger rig of clean flue gas intensification and waste heat recovery after the wet desulphurization " (separate case is applied for a patent); Use three phase-change heat-exchange independent of each other unit; In order to low temperature exhaust heat that absorbs former flue gas and the clean flue gas that heating need heat up, the thermal source that wherein heats the III level phase-change heat-exchanger of clean flue gas derives from the steam that the steam turbine bleeding point is introduced respectively.But; When supposing that the original air preheater heat balance of boiler leaves the safe budget about 20～30%; If not using the device that proposes here, and continue to continue to use the method that another patent provides, promptly through the described III level of this patent phase-change heat-exchanger; The clean flue gas of low-pressure steam indirect that utilization is extracted out from the steam turbine bleeding point; Identical purpose with clean smog discharge temperature after the realization raising sulphur removal then not only causes the initial investment of equipment higher relatively, but also has operation complicacy and the relative problem that improves of this part operating cost.
Summary of the invention
The objective of the invention is to overcome the deficiency of prior art in specific operation; Provide a kind of power plant with energy-saving and water-saving sulphur removal integrated system; The present invention passes to the heat energy of boiler flue flue gas the cleaned air that gets into before the air preheater; Again from air preheater outlet to the direct input temp in desulfurizing tower rear end up to the high-quality cleaned air more than 330～350 ℃, mixes with the clean flue gas of the low temperature in desulfurizing tower exit, to realize the temperature of the clean flue gas of lifting; Reach the requirement that causes the boiler smoke exhaust temperature; Thereby when having heated the air preheater air intake, also save from the steam turbine bleeding point introduce saturated vapor lifting exhaust gas temperature heat exchanger and with a series of equipment that this heat exchanger matches, greatly reduced the initial stage manufacturing cost and operation complexity of entire equipment.
The present invention realizes through following technical scheme:
One of optional following two kinds structure of the present invention:
Structure one; Comprise: I level phase-change heat-exchanger, mixing chamber and control system; I level phase-change heat-exchanger places after the air preheater of boiler back end ductwork; Connect mixing chamber through pipeline, mixing chamber is connected with the air outlet slit of the air preheater of steam generator system through pipeline, and I level phase-change heat-exchanger all is connected through being wired to the control system with mixing chamber.
Structure two; Comprise: I level phase-change heat-exchanger, mixing chamber, II level phase-change heat-exchanger and control system; I level phase-change heat-exchanger places after the air preheater of boiler back end ductwork, connects mixing chamber through pipeline, between the desulfurization blower fan of steam generator system and desulfurizing tower, II level phase-change heat-exchanger is set; Mixing chamber is connected with the air outlet slit of the air preheater of steam generator system through pipeline, and I level phase-change heat-exchanger all is connected through being wired to the control system with mixing chamber.
Described II level phase-change heat-exchanger comprises: II level phase-change heat-exchanger phase transformation epimere, II level phase-change heat-exchanger phase transformation hypomere, be terminated in the air duct on the II level phase-change heat-exchanger phase transformation hypomere, and be terminated in the exhaust gases passes under the II level phase-change heat-exchanger phase transformation hypomere.
Said I level phase-change heat-exchanger comprises: drum, demineralized water flow control valve, I level phase-change heat-exchanger phase transformation hypomere; I level phase-change heat-exchanger phase transformation hypomere is arranged in the air preheater flue afterwards of steam generator system; Be connected in series with four equipment of steam generator system after the phase transformation hypomere of I level phase-change heat-exchanger successively: deduster, air-introduced machine, desulfurization blower fan, desulfurizing tower; Be connected with mixing chamber afterwards, receive at last on the fume extractor chimney; The phase transformation hypomere upper end of I level phase-change heat-exchanger is connected to air preheater.
Described I level phase-change heat-exchanger phase transformation hypomere comprises: heat exchange fin tube bank, header, central dividing plate; Wherein: the heat exchange fin tube bank is fixedly set between the header of top and bottom; And it is perpendicular with the flue gas direction of desulfurizing tower output; The top of header is connected with drum, and it is vertical with the heat exchange fin tube bank that central dividing plate is placed on middle part, phase transformation lower end, divides I level phase-change heat-exchanger phase transformation hypomere upper end and I level phase-change heat-exchanger phase transformation hypomere lower end with I level phase-change heat-exchanger phase transformation hypomere.
Described mixing chamber is an enclosure space, connects two inlet ducts and an outlet conduit, and wherein an inlet duct is clean gas approach, and another inlet duct is the hot-air inlets that comes from air preheater; Outlet connects chimney.
Said mixing chamber is located at outside the chimney, also can be located at the bottom within the chimney.
The wall surface temperature signal of the said control reception I of system level phase-change heat-exchanger phase transformation hypomere and the temperature signal of mixing chamber mist; Control air mass flow that gets into I level phase-change heat-exchanger phase transformation hypomere upper end and the air mass flow that gets into mixing chamber, reach the correlation technique requirement with normal operation and the smog discharge temperature that guarantees equipment.
The present invention is directed in boiler plant; The clean flue gas dew point temperature that gets into the former flue gas on absorption tower and flow out from the absorption tower differs bigger; The higher flue gas heater that causes easily of the dew-point temperature of clean flue gas cold end corrosion occurs until this problem of inefficacy, and the dividing wall type flue gas heater of normal use has been led in the cancellation of novelty, and will place the former fume side phase-change heat-exchanger heating cleaned air that absorbs energy; And through after air preheater further is heated to higher temperature; Directly mix, promote the exhanst gas outlet temperature of chimney with the clean flue gas of low temperature, thus the problem of avoiding the at present clean existing cold end corrosion of flue gas heater at all and causing entire equipment to lose efficacy; And save install the lifting flue gas the needed cost of heat transmission equipment that will use, the initial investment expense of having saved equipment by a relatively large margin.In addition, at the low temperature exhaust heat that fully uses former flue gas, when improving the whole generating system thermal efficiency, also brought into play positive role for practicing thrift most valuable water resource significantly.
Description of drawings
Fig. 1 is the structural representation of application examples one.
Fig. 2 is the structural representation of application examples two;
Among the figure: boiler 1, air preheater 2, air connect pipeline 3, I level phase-change heat-exchanger 4, deduster 5, air-introduced machine 6, desulfurization blower fan 7, by-pass flue 8, II level phase-change heat-exchanger 9, desulfurizing tower 10, mixing chamber 11, chimney 12, hot-air duct 13, control system 14.
Fig. 3 is that mixing chamber working medium flows to sketch map.
Among the figure: clean gas approach thermometer 305, mixed flue gas outlet temperature meter 307, clean gas approach flowmeter 306, mixed flue gas rate of discharge meter 308, assignment of traffic control valve 309.
Fig. 4 is an I level phase-change heat-exchanger structural representation;
Among the figure: drum 101, phase transformation hypomere 102, phase transformation hypomere upper end 121, phase transformation hypomere lower end 122, central dividing plate 103, heat exchange fin tube bank 104, header 105, I level phase-change heat-exchanger temperature measurer 301, I level phase-change heat-exchanger demineralized water flow control valve 303.
Fig. 5 is an II level phase-change heat-exchanger structural representation.
Among the figure: drum 201, phase transformation hypomere 202, phase transformation hypomere upper end 221, phase transformation hypomere lower end 222, central dividing plate 203, heat exchange fin tube bank 204, header 205, II level phase-change heat-exchanger temperature measurer 302, II level phase-change heat-exchanger demineralized water flow control valve 304.
The specific embodiment
Below in conjunction with accompanying drawing embodiments of the invention are elaborated, present embodiment provided detailed embodiment and concrete operating process, but protection scope of the present invention is not limited to following embodiment being to implement under the prerequisite with technical scheme of the present invention.
Embodiment one
Present embodiment comprises: I level phase-change heat-exchanger 4, mixing chamber 11, control system 14; I level phase-change heat-exchanger 4 places after the air preheater 3 of boiler back end ductwork; Connect mixing chamber 11 through pipeline; Mixing chamber 11 is connected with the air outlet slit of the air preheater 3 of steam generator system through pipeline, and I level phase-change heat-exchanger 4 all is connected through being wired to control system 14 with mixing chamber 11.
The said I level of present embodiment phase-change heat-exchanger 4 comprises: drum 101, demineralized water flow control valve 303, phase transformation hypomere 102; Phase transformation hypomere 102 is arranged in the flue after the steam generator system air preheater 3; Be connected in series with four equipment of steam generator system after the phase transformation hypomere lower end 122 of I level phase-change heat-exchanger 4 successively: deduster 5, air-introduced machine 6, desulfurization blower fan 7, desulfurizing tower 10; Be connected with mixing chamber 11 afterwards, receive at last on the fume extractor chimney 12; The phase transformation hypomere upper end 121 of I level phase-change heat-exchanger 4 is connected to the air outlet slit of air preheater 4.
The described phase transformation hypomere 102 of present embodiment comprises: heat exchange fin tube bank 104, header 105, central dividing plate 103; Wherein: heat exchange fin tube bank 104 is fixedly set between the header 105 of top and bottom; And it is perpendicular with the flue gas direction; The top of header 105 is connected with drum 101, and central dividing plate 103 is placed on phase transformation hypomere 102 middle parts and heat exchange fin and restrains 104 vertically, and phase transformation hypomere 102 is divided into phase transformation hypomere upper end 121 and 122 two parts in phase transformation hypomere lower end.
The described mixing chamber 11 of present embodiment is an enclosure space, connects two inlet ducts and an outlet conduit, and wherein an inlet duct is clean gas approach, and another inlet duct is the hot-air inlets that comes from air preheater; Outlet conduit connects chimney 12.
The said mixing chamber 11 of present embodiment is located at outside the chimney 12, also can be located at the bottom within the chimney 12.
The said control of present embodiment system 14 receives the wall surface temperature signal of I level phase-change heat-exchanger 4 phase transformation hypomeres 102 and the temperature signal of mixing chamber 11 mists; Control demineralized water flow that gets into I level phase-change heat-exchanger 4 drums 101 and the air mass flow that gets into mixing chamber 11, reach the correlation technique requirement with normal operation and the smog discharge temperature that guarantees equipment.
Outstanding technological progress and significant useful effect that present embodiment can obtain through following embodiment and process:
The metallic walls surface temperature that contacts with former flue gas in the present embodiment I level phase-change heat-exchanger 4 is controlled at former flue gas all the time and possibly occurs on the temperature of low temperature dewfall, promptly is operated among usually said " first place of safety ".In the low temperature exhaust heat that former flue gas reclaimed; Except being used as the heating demineralized water; Also in I level phase-change heat-exchanger 4, set up the air before air preheater is heated in upper end 121 preheatings of phase transformation hypomere; Adopt central dividing plate 103 that phase transformation hypomere upper end 121 is separated with phase transformation hypomere lower end 122; A part of heat that phase transformation hypomere lower end 122 is absorbed from former flue gas is used as preheated air, not only can improve the condition of work of air preheater 2, also often further improves the thermal efficiency of boiler because improving burning; Normal temperature air through 121 preheatings of phase transformation hypomere upper end after; Connect the air preheater 2 that pipeline 3 gets into steam generator system through air again; That is to say; Between the air preheater 2 of steam generator system and I level phase-change heat-exchanger 4, air is set and is connected pipeline 3, a high temperature air part of coming out from air preheater 2 flows to boiler and participates in burning, and another part gets into mixing chambers through hot-air duct 13.
Present embodiment mixing chamber 11 connects air preheater 2 through pipeline; (flue gas without desulfurization before getting into desulfurizing tower is called former flue gas when the former flue gas of the air preheater of steam generator system 2 outlets; Be called clean flue gas through the flue gas after the desulfurization) the 122 temperature reductions after heat release of entering phase transformation hypomere lower end; Its energy is converted into the latent heat of vaporization that phase transformation hypomere 102 inside are in the intermediate medium in the phase transformation state in principle all the time; And the higher intermediate medium of contained gas phase composition rises to drum 101, through in the condensation heat the lower demineralized water of heat transferred temperature, demineralized water after being heated gets into the oxygen-eliminating device of power plant system; On the other hand; The former flue gas of low temperature that comes from phase transformation hypomere lower end 122 passes through deduster 5, air-introduced machine 6 and the desulfurization blower fan 7 of steam generator system successively; Then get into desulfurizing tower 10 desulfurization of steam generator system and further cooling; Mixing chamber 11 mixes with high temperature air from air preheater 2 and is reheated intensification and the clean flue gas of low temperature that comes from the desulfurizing tower 10 of steam generator system is flowed through, and is disposed to atmosphere through chimney 12 at last.The I level phase-change heat-exchanger temperature measurer 301 metallic walls surface temperature signals that contact with former flue gas in the I level phase-change heat-exchanger 4 of surveying send to control system 14; Control system 14 is through computing, and the aperture of regulating I level phase-change heat-exchanger demineralized water control valve 303 is to form the closed-loop control to the metallic walls surface temperature.Simultaneously; As shown in Figure 3; Control system 14 is according to the running parameter of setting; And gather the clean gas approach thermometer 305 be arranged on mixing chamber 11 clean gas approach and mixed flue gas exit, mixed flue gas outlet temperature meter 307, the data of gas approach flowmeter 306, mixed flue gas rate of discharge meter 308 only, real-time regulated is used for the aperture of the assignment of traffic control valve 309 of control air preheater 2.
The above-mentioned all devices of present embodiment, as shown in Figure 1, form one interrelated, interdependent and by control system 14 heat exchanger system of control in real time in addition each other.
Embodiment two
As shown in Figure 2, should use-case on the basis of above-mentioned application examples one, further save the energy, above-mentioned application examples one structure is made further improvement: II level phase-change heat-exchanger 9 is set on the flue between desulfurization blower fan 7 and the desulfurizing tower 10.
As shown in Figure 5; The structure of II level phase-change heat-exchanger 9, function are identical with I level phase-change heat-exchanger 4; Be divided into phase transformation hypomere upper end 221 and phase transformation hypomere lower end 222 by central dividing plate 203; Phase transformation hypomere upper end 221 is connected in the air duct, and phase transformation hypomere lower end 222 is connected in the exhaust gases passes, with the fume afterheat preheated air and the boiler demineralized water that absorb.The difference of II level phase-change heat-exchanger 9 and I level phase-change heat-exchanger 4 is exactly that the temperature spot of each Self Control is different, and manufacture craft has any different, and is set in second place of safety like II level phase-change heat-exchanger 9 wall temperatures, and the metal surface scribbles anticorrosive coat.The metallic walls surface temperature that control system 14 records according to II level phase-change heat-exchanger temperature measurer 302 is regulated the demineralized water flow and is formed the closed-loop control to II level phase-change heat-exchanger 9 metallic walls surface temperatures.Owing to set up II level phase-change heat-exchanger 9; Utilize the waste heat of flue gas more fully, the flue-gas temperature that gets into desulfurizing tower 10 is further reduced, utilized the waste heat of flue gas more fully; Help follow-up sulphur removal, and further reduce the water consumption of desulfurizing tower 10.
The high-temperature flue gas that present embodiment comes out from boiler 1; For the first time cool to T1 ℃ through air preheater 2; Get into then that I level phase-change heat-exchanger 4 is passed to air to flue gas heat energy and demineralized water is lowered the temperature once more; I level phase-change heat-exchanger wall temperature is controlled at T2 ℃, and exit gas temperature is higher about 15 ℃ than wall surface temperature; Flue gas under this temperature passes through deduster 5, air-introduced machine 6, desulfurization blower fan 7 successively then; Get into II level phase-change heat-exchanger 9 and pass to air and demineralized water to flue gas heat energy once more; These II level phase-change heat-exchanger 9 wall surface temperatures are controlled at T3 ℃; This temperature is lower than dew-point temperature, is in second place of safety, and the outlet exhaust gas temperature is higher about 15 ℃ than T3; Low-temperature flue gas under this temperature gets into desulfurization in the desulfurizing tower 10, and the clean flue-gas temperature behind the desulfurizing tower 10 will reduce once again, and outlet temperature is T4 ℃; Clean flue gas behind the desulfurizing tower 10 gets into mixing chamber 11 subsequently, mixes fully at mixing chamber 11 with the hot-air that comes via bypass duct 13 from air preheater 2 and heats up afterwards from smoke stack emission, makes the exhaust temperature of flue gas be higher than 80 ℃ of the emission requests of national regulation all the time.
The present invention was provided with the II level phase-change heat-exchanger 9 that works in " second place of safety " before desulfurizing tower 10 when implementing.The mechanism that the basic difference of II level phase-change heat-exchanger 9 and I level phase-change heat-exchanger 4 is to control cold end corrosion is different, in requisition for the wall surface temperature point difference of control, and the difference of corresponding service condition with it and manufacture craft.For example, to application scenario described herein, because handle the problem that " ash is stifled " can not appear in later clean flue gas in principle again, so generally speaking allow to be provided with the II level phase-change heat-exchanger 9 that is operated in " second place of safety " through deduster.Obviously, for the phase-change heat-exchanger that is operated in " first place of safety ", just cold end corrosion should not occur as long as its wall surface temperature is not less than the temperature of setting, and high more of wall surface temperature can be safe more.But; Different fully with it; When phase-change heat-exchanger was operated in " second place of safety ", its wall surface temperature must be strict controlled on " temperature spot it " of " second place of safety " defined, can not be lower than the temperature of setting; The temperature that can not be higher than setting, otherwise intolerable cold end corrosion phenomenon all can appear.At this moment, also need be coated with anticorrosive coat with the metal surface that former flue gas contacts, incite somebody to action in principle inevitably " cold end corrosion " and reasonably be controlled on certain minimum " reaction rate " at heat exchanger.Certainly, set up II level phase-change heat-exchanger 9 here, purpose is to be used as and further reduces the former flue-gas temperature that flows out I level phase-change heat-exchanger 4 and raise to some extent because having absorbed air-introduced machine and sulphur removal blower fan acting institute's produce power.
As shown in Figure 5, set up the system of II level phase-change heat-exchanger
Wherein, I level phase-change heat-exchanger 4 is arranged between the air preheater 2 and deduster 5 of steam generator system, realizes that the minimum metallic walls surface temperature of control need be more than former flue gas dew point temperature (for example 80 ℃).In the energy that this heat exchanger discharges, a part improves the thermal efficiency of boiler simultaneously as the condition of work of heating and normal-temperature air with the air preheater 2 that improves steam generator system at former flue gas, and another part is then as the heating demineralized water.Work in the occasion of the II level phase-change heat-exchanger 9 of " second place of safety " in setting; Demineralized water to be heated is at first by 9 heating of II level phase-change heat-exchanger; Get into again and place deduster 5 I level phase-change heat-exchanger 4 before by the continuation heating, with the temperature of further lifting oneself.
Should be noted that; When having the phase transformation hypomere lower end 122 of fin in the flue gas process I level phase-change heat-exchanger 4 of treating release heat; The heat that flue gas discharges will be used to heat the phase-change working substance that is in saturation state all the time; The phase-change working substance that gets into phase transformation hypomere upper end 121, drum 101 is in the state of all pressing samming; Also make simultaneously to contact, exist the possible metal wall corresponding position of cold end corrosion among the state of temperature of homogenising, thereby be the controllable condition that provides of metallic walls surface temperature with flue gas; Heat the demineralized water or the process of normal temperature air and the heat exchanger of general type as for phase-change working substance and do not have difference; And discharged the latent heat of vaporization so the big phase-change working substance that has increased of high humidity, and get into evaporimeter again and accept the energy of flue gas release again through down-comer and next part case, so move in circles by means of this, I level phase-change heat-exchanger 4 is able to operate as normal.Generally speaking, the metallic walls surface temperature of I level phase-change heat-exchanger 4 is achieved by means of the heated demineralized water water yield of control.
But, being arranged on the II level phase-change heat-exchanger 9 of " second place of safety ", its mechanism that overcomes " cold end corrosion influence " is different from the phase-change heat-exchanger that works in " first place of safety " fully.On the metal wall, be bound to occur acid solution during flue gas generation low temperature dewfall; And the concentration of acid solution and metallic walls surface temperature produce opposite influence to " rate of metal corrosion "; And so-called " second place of safety " is exactly to utilize this characteristic, and " corrosion rate " of metal wall is controlled on minimum relatively, the level that people can reasonably accept.Therefore; Must be higher than more than the temperature (as 80 ℃) that causes low temperature dewfall phenomenon with the wall surface temperature of the phase-change heat-exchanger that requires to work in " first place of safety "; It is different thereby " cold end corrosion " phenomenon can not occur; For the heat exchanger that is operated in " second place of safety ", its metallic walls surface temperature often much lower (as 35-55 ℃), thus be further to reduce entering desulfurizing tower 10 former flue-gas temperature before possibility is provided.
Present embodiment is from the thermal conduction study angle analysis; The II level phase-change heat-exchanger 9 that works in " second place of safety " must satisfy following primary condition: the metal that contacts with flue gas in (1) heat exchanger, its wall surface temperature must be in more strict all even controllable state; (2) control device must satisfy " two-way controllable " requirement, can not be lower than also not allow to be higher than preset metallic walls surface temperature; (3) still need keep enough temperature and pressure, for example at gas side one end, the minimum temperature difference of itself and metal wall must not be lower than 15 ℃, and at liquid side one end, and the minimum temperature difference of itself and metal wall must not be lower than 10 ℃; (4) flue gas must not contain ash content; (5) metal surface need increase the deposited coating that satisfies corrosion-resistant requirement.Therefore, if compare,, on the structure of anticorrosive mechanism, relative set and even mode of connection, all there are some careful and material differences for II level phase-change heat-exchanger 9 with the phase-change heat-exchanger of general type in the past.
11 of embodiments of the invention mixing chambers are arranged between the dehydrating unit and chimney 12 at desulfurizing tower 10 rear portions; As shown in Figure 3; Its temperature of clean flue gas that gets into mixing chamber 11 is generally about 50 ℃, and the temperature (as 80 ℃) that need be heated to the discharge standard defined enters atmosphere via chimney again.So need flow and state of temperature, use the hot-air of corresponding desired flow to mix with it to improve the exhaust temperature of flue gas to clean flue gas.
Claims (6)
1. a power plant is characterized in that with energy-saving and water-saving sulphur removal integrated system, one of optional following two kinds structure:
Structure one; Comprise: I level phase-change heat-exchanger, mixing chamber and control system; I level phase-change heat-exchanger places after the air preheater of boiler back end ductwork; Connect mixing chamber through pipeline, mixing chamber is connected with the air outlet slit of the air preheater of steam generator system through pipeline, and I level phase-change heat-exchanger all is connected with the control system through wiring with mixing chamber;
Structure two; Comprise: I level phase-change heat-exchanger, mixing chamber, II level phase-change heat-exchanger and control system; I level phase-change heat-exchanger places after the air preheater of boiler back end ductwork; Connect mixing chamber through pipeline, between the desulfurization blower fan of steam generator system and desulfurizing tower, II level phase-change heat-exchanger is set, mixing chamber is connected with the air outlet slit of the air preheater of steam generator system through pipeline; I level phase-change heat-exchanger all is connected through being wired to the control system with mixing chamber, and II level phase-change heat-exchanger is connected with the control system;
Described mixing chamber is an enclosure space, connects two inlet ducts and an outlet conduit, and wherein an inlet duct links to each other with desulfurizing tower as clean gas approach, and another inlet duct is the hot-air inlets that comes from air preheater; Outlet connects chimney;
Said I level phase-change heat-exchanger comprises: drum, demineralized water flow control valve, I level phase-change heat-exchanger phase transformation hypomere; I level phase-change heat-exchanger phase transformation hypomere is arranged in the air preheater flue afterwards of steam generator system; Be connected in series with four equipment of steam generator system after the I level phase-change heat-exchanger phase transformation hypomere successively: deduster, air-introduced machine, desulfurization blower fan, desulfurizing tower; Be connected with mixing chamber afterwards, receive at last on the fume extractor chimney; Divide I level phase-change heat-exchanger phase transformation hypomere upper end and I level phase-change heat-exchanger phase transformation hypomere lower end with I level phase-change heat-exchanger phase transformation hypomere, the phase transformation hypomere upper end of I level phase-change heat-exchanger is connected to air preheater.
2. power plant according to claim 1 is with energy-saving and water-saving sulphur removal integrated system; It is characterized in that; Described II level phase-change heat-exchanger; Comprise: II level phase-change heat-exchanger phase transformation epimere, II level phase-change heat-exchanger phase transformation hypomere, be terminated in the air duct on the II level phase-change heat-exchanger phase transformation hypomere, be terminated in the exhaust gases passes under the II level phase-change heat-exchanger phase transformation hypomere.
3. power plant according to claim 2 is characterized in that with energy-saving and water-saving sulphur removal integrated system described II level phase-change heat-exchanger metal surface scribbles anticorrosive coat.
4. power plant according to claim 1 is with energy-saving and water-saving sulphur removal integrated system; It is characterized in that; Described I level phase-change heat-exchanger phase transformation hypomere comprises: heat exchange fin tube bank, header, central dividing plate, and wherein: the heat exchange fin tube bank is fixedly set between the header of top and bottom, and perpendicular with the flue gas direction of desulfurizing tower output; The top of header is connected with drum, and it is vertical with the heat exchange fin tube bank that central dividing plate is placed on middle part, phase transformation lower end.
5. power plant according to claim 1 is characterized in that with energy-saving and water-saving sulphur removal integrated system described mixing chamber is located at outside the chimney, perhaps is located at the bottom within the chimney.
6. power plant according to claim 1 is with energy-saving and water-saving sulphur removal integrated system; It is characterized in that; The wall surface temperature signal of the said control reception I of system level phase-change heat-exchanger phase transformation hypomere and the temperature signal of mixing chamber mist, control gets into the air mass flow of I level phase-change heat-exchanger phase transformation hypomere upper end and the air mass flow that gets into mixing chamber.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010105279573A CN101995028B (en) | 2010-11-02 | 2010-11-02 | Energy and water saving desulphuration integrated system for power plant |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010105279573A CN101995028B (en) | 2010-11-02 | 2010-11-02 | Energy and water saving desulphuration integrated system for power plant |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101995028A CN101995028A (en) | 2011-03-30 |
| CN101995028B true CN101995028B (en) | 2012-01-11 |
Family
ID=43785527
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2010105279573A Expired - Fee Related CN101995028B (en) | 2010-11-02 | 2010-11-02 | Energy and water saving desulphuration integrated system for power plant |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101995028B (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102393024A (en) * | 2011-11-10 | 2012-03-28 | 王海波 | Composite phase change heat exchange device for boiler flue gas waste heat recovery |
| CN103776045B (en) * | 2014-01-16 | 2016-02-24 | 西安交通大学 | The method and system of a kind of wet bottom boiler lime-ash heat recovery |
| CN105202945A (en) * | 2015-07-27 | 2015-12-30 | 南通昊友食品添加剂有限公司 | Waste heat recycling system |
| CN106196132B (en) * | 2016-08-30 | 2018-10-12 | 江苏海德节能科技有限公司 | Energy saving heat transfer flue device |
| CN106196121B (en) * | 2016-08-30 | 2018-07-10 | 江苏海德节能科技有限公司 | Fume afterheat water conservancy diversion heat-exchanger rig |
| CN108534170A (en) * | 2018-03-30 | 2018-09-14 | 珠海市华远自动化科技有限公司 | A kind of boiler smoke wind blending heating regulating system and its control method |
| CN112783231B (en) * | 2021-01-05 | 2022-03-22 | 中国大唐集团科学技术研究院有限公司华中电力试验研究院 | Advanced control system for circulating water temperature of thermal power plant |
| CN114135890B (en) * | 2021-12-06 | 2023-09-12 | 北京运江科技有限公司 | Comprehensive treatment system for flue gas and control method thereof |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2368001Y (en) * | 1999-04-23 | 2000-03-08 | 杨本洛 | Integrated heat-pipe type compound phase transition heat exchanger |
| CN1206473C (en) * | 2002-08-21 | 2005-06-15 | 杨本洛 | Mixed composite phase change heat exchanger |
| CN101398267A (en) * | 2007-09-28 | 2009-04-01 | 杨本洛 | Internal circulation composite phase change heat exchanger |
| CN101629713A (en) * | 2009-08-19 | 2010-01-20 | 深圳中兴科扬节能环保股份有限公司 | Flue gas afterheat recovery system |
| CN101634457A (en) * | 2009-08-19 | 2010-01-27 | 深圳中兴科扬节能环保股份有限公司 | Flue-gas waste heat reclaiming system |
| CN101709879A (en) * | 2009-09-27 | 2010-05-19 | 西安交通大学 | System for deep cooling and waste heat recovery of smoke gas in boiler |
| CN201517780U (en) * | 2009-08-19 | 2010-06-30 | 深圳中兴科扬节能环保股份有限公司 | Smoke gas waste heat recovery system |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4959156B2 (en) * | 2004-11-29 | 2012-06-20 | 三菱重工業株式会社 | Heat recovery equipment |
-
2010
- 2010-11-02 CN CN2010105279573A patent/CN101995028B/en not_active Expired - Fee Related
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2368001Y (en) * | 1999-04-23 | 2000-03-08 | 杨本洛 | Integrated heat-pipe type compound phase transition heat exchanger |
| CN1206473C (en) * | 2002-08-21 | 2005-06-15 | 杨本洛 | Mixed composite phase change heat exchanger |
| CN101398267A (en) * | 2007-09-28 | 2009-04-01 | 杨本洛 | Internal circulation composite phase change heat exchanger |
| CN101629713A (en) * | 2009-08-19 | 2010-01-20 | 深圳中兴科扬节能环保股份有限公司 | Flue gas afterheat recovery system |
| CN101634457A (en) * | 2009-08-19 | 2010-01-27 | 深圳中兴科扬节能环保股份有限公司 | Flue-gas waste heat reclaiming system |
| CN201517780U (en) * | 2009-08-19 | 2010-06-30 | 深圳中兴科扬节能环保股份有限公司 | Smoke gas waste heat recovery system |
| CN101709879A (en) * | 2009-09-27 | 2010-05-19 | 西安交通大学 | System for deep cooling and waste heat recovery of smoke gas in boiler |
Also Published As
| Publication number | Publication date |
|---|---|
| CN101995028A (en) | 2011-03-30 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101995028B (en) | Energy and water saving desulphuration integrated system for power plant | |
| CN102012036B (en) | Composite phase-transition heat exchanging device for warming clean gas fume and recovering exhaust heat after wet desulphurization | |
| CN206950940U (en) | High energy efficiency flue gas desulphurization system | |
| JP5913369B2 (en) | Non-contact exhaust residual heat sludge drying system | |
| CN101706106B (en) | Recovering device for afterheat of garbage incineration furnace | |
| JP2015525863A (en) | Co-current boiler flue gas residual heat recovery system | |
| CN102401554A (en) | Drying system for plaster slab | |
| CN109945277A (en) | A kind of energy conserving system being used for central heating using electric heat pump depth recycling remaining heat of flue gas from steam power plant | |
| CN201028791Y (en) | Anti-corrosion energy-saving boiler flue gas residual heat utilization device | |
| CN108469033A (en) | A kind of dehumidifying decontamination heating of flue gas condensing disappears white heat exchanger | |
| CN210197331U (en) | Combined system for eliminating smoke plume and utilizing low-grade flue gas waste heat | |
| CN102121703A (en) | Mixed type flue gas reheating system suitable for wet type flue gas purification process of high-cold region | |
| CN204421043U (en) | Off-gas recovery deep condensation device | |
| CN201706510U (en) | Waste incineration boiler afterheat recovering device | |
| CN102533302A (en) | Internal heating type dryer for in-furnace coking coal dehumidification | |
| CN202511307U (en) | Compound phase change heat exchange system for recycling boiler flue gas waste heat | |
| CN206669688U (en) | A kind of multichannel exhaust-heat boiler system equipment | |
| CN208735652U (en) | The eliminating white smoke system that a kind of heat exchanger and air preheater combine | |
| CN109731431A (en) | A kind of coal steam-electric plant smoke takes off white system and method | |
| CN202492499U (en) | Internal heating type dryer for dehumidifying coking coal entering into furnace | |
| CN201014754Y (en) | Flue gas waste heat utilization device of corrosion-proof energy-saving type industry boiler | |
| CN201259210Y (en) | Non-phase-change composite heat exchanger | |
| CN208591715U (en) | Energy-saving combustion gas suitable for medium small boiler takes off white device | |
| CN210874732U (en) | Flue gas deep cooling, condensation remove white system in coordination | |
| CN208332300U (en) | A kind of system emitting white cigarette using the waste heat elimination chimney of desulfurization slurry |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20120111 Termination date: 20121102 |