Tower direct air cooled condenser and tower direct dry cooling-system thereof
Technical field
The invention belongs to fire (nuclear) exhaust steam of electric power plant dry type and cool off the technical field that makes exhaust steam become condensate water, particularly a kind of tower direct air cooled condenser and tower direct dry cooling-system thereof.
Background technology
Every of thermal power generation is electric energy once, adopts dry type cooling (being commonly called as air cooling), than adopting the wet type cooling to save the water of 2.5kg.Classical dry cooling systems is between mixed in the following table, between table and direct-cooled three kinds of systems.Three kinds of systems by classics derive again remaining six kinds of cooling system in the following table.
It is dry cooling system that developed country has all renamed as air cooling system, and at present, China is the term of standard dry type cooling not yet, and ambiguity is more, and preciseness is not enough.For power station cooling, heat exchanger, radiator, condenser and clammy, dry cooling-system can be defined as follows:
Dry type is cooled off significant water-saving result must cause increasing of the large and operating cost of the change of system investment.The little defective of existing dry cooling systems and the deficiency of suitability force people to change thinking, and the advantage of integrated various cooling systems is used for reference mutually.
Over more than 50 year, the power plant unit capacity that the whole world is equipped with the dry type cooling has reached 200,000,000 kilowatts.China's (mainly being over nearly 10 years) is built and at the cold-dry type generating set of building, and installed capacity also surpasses 100,000,000 kilowatts, and single-machine capacity differs in size from 2MW to 1000MW, and over thousands of cover dry cooling systems is arranged.The dry type cooling generating of " changing water with coal ", coal consumption is than the large-scale unit of clammy high 5%() to the little unit of 10%().China's dry type cooling generating, about 1,000,000,000 tons of annual water saving needs 7,000,000 tons in many consumption mark coals.Along with constantly riseing of coal price, the power plant faces to economize on water also wants energy-conservation awkward situation, is badly in need of the new dry type cooling technology of research and development.In following 20 years, China at least also will build the dry type cooling power plant of 100,000,000 kilowatts of installation total capacities, be badly in need of improving key technology and equipment.
The ACC system is simple because of system, flexible operation, initial cost are low, and the heat exchange number of times is few and efficient is high, is favored.But along with the lifting of environmental requirement, the ACC system noise disturbs residents and highlights; The ACC system is to wind direction (colder than the between) sensitivity of strong wind, and fan power consumption is larger.The ACC system runs into the policy bottleneck at Evaluation on Energy Saving, also has, force in the performance assessment criteria of some gencos to list in station service power consumption rate [lose just and sound, should only examine the generating can (coal) consumption, comparatively reasonable.For example, the examination station service power consumption rate force the feed pump of some power plant to abandon driven by power, is used steam drive instead] so that the ACC system and a cold scheme comparison in run into unprecedented difficulty.Therefore, keep the advantage of ACC, eliminate fan energy consumption and noise and reduction strong wind sensitiveness, for the research of dry type cooling clear and definite direction.
Belgian HAMON LUMMUS companies in 1993 at first propose the concept of Natural Draft Condenser, the NDC system of namely extensively being talked about afterwards, and its key concept is exactly the fan forced-air blast that substitutes the ACC system with cooling tower with natural air exhaust.But this research only rests on the horizontally disposed aspect of the interior ridge of air cooling tubes condenser tower, briefly, removes exactly the fan of ACC system, and ACC is put in the cooling tower.The said firm is that the conceptual design of a 200MW unit outfit dry cooling tower of Fedtsch wild goose pond two power plant is: tower overall height H=94m, and tower bottom diameter D=83m, air inlet height h10m fails to enter practical stage.
German GEA company proposed Natural Draft Air Cooled Condenser concept in 1994, i.e. the NDACC system that extensively copied of its figure afterwards.October nineteen ninety-five, Germany GEA company was that the Preliminary design of a 200MW unit outfit dry cooling tower of Fedtsch wild goose pond two power plant is: tower overall height H115m, tower bottom diameter D127m, air inlet height h14m, air cooling tubes condenser still is ridge in tower horizontally disposed, the bottom has additional shutter, but also fails to enter practical stage.
Summary of the invention
The object of the present invention is to provide a kind of tower direct air cooled condenser and tower direct dry cooling-system thereof, the ACC system is simple to keep, flexible operation, initial cost are low, the heat exchange number of times is few and advantage that efficient is high, eliminates ACC system fan energy consumption and noise, reduction to the sensitiveness of wind direction.
To achieve these goals, the present invention adopts following technical scheme:
A kind of tower direct air cooled condenser comprises scroll casing shape steam distribution main and some condensing units; Condensing unit comprises that standpipe, following current tube bank, adverse current tube bank and adverse current following current distribute inclined clapboard; Standpipe comprises joins vapour standpipe and discharge, joins the adverse current following current is installed between vapour standpipe and the discharge distributes inclined clapboard, joins that vapour standpipe and discharge vertically arrange and discharge is positioned at and joins vapour standpipe top; Described standpipe tilts first row tube bank and second row tube bank is installed downwards; The first row tube bank comprises a plurality of following current tube bank and a plurality of adverse current tube banks that are installed on the discharge of joining on the vapour standpipe that are installed on; The tube bank of the second comb is arranged symmetrically with centered by restraining to join the vapour standpipe with first row; The described vapour standpipe of joining connects described scroll casing shape steam distribution main; Following current tube bank and interval setting parallel with the adverse current tube bank, the end under the following current tube bank of same row and adverse current tube bank are tilted to all is connected to a condensate water collecting standpipe.
The present invention further improves and is: the skewed layout of the Eight characters that first row tube bank and second row tube bank consist of.
The present invention further improves and is: the angle between following current tube bank and adverse current tube bank and the horizontal plane is α=30~60 °.
The present invention further improves and is: described some condensing units are circular layout, and adjacent condensing unit shares a condensate water collecting standpipe.
The present invention further improves and is: collecting pipe connects buried receipts condensate water collection endless tube, and buried receipts condensate water collection endless tube is by going the condensate tank carrier pipe to connect condensate tank.
The present invention further improves and is: discharge is connected with vacuum-pumping pipeline; Condensate tank connects scroll casing shape steam distribution main by drainage pump, and condensate tank also is connected with condensate pump; Vacuum-pumping pipeline connects scroll casing shape steam distribution main, and vacuum-pumping pipeline connects condensate tank by the liquid-ring type vacuum pumping pump.
The present invention further improves and is: the top of scroll casing shape steam distribution main reduces gradually to terminal internal diameter.
A kind of tower direct dry cooling-system comprises tower direct air cooled condenser; Described tower direct air cooled condenser is arranged at armored concrete hyperbolic-type cooling tower bottom, some condensing units are circular layout, the vapour standpipe of joining of some condensing units all connects scroll casing shape steam distribution main, and the discharge of some condensing units all connects vacuum-pumping pipeline; Armored concrete hyperbolic-type cooling tower inside is provided with the crosswise wind isolation board.
The present invention further improves and is: the top of described tower direct air cooled condenser is provided with the oblique bridging piece of armored concrete at the cooling tower ring beam place; The collecting pipe both sides respectively are provided with two hooks, and glass fiber reinforced plastic wind deflector is movably installed between two collecting pipes by described hook; Be stamped the triangular aslant cover plate on the two comb bundles of adjacent condensing unit.
With respect to prior art, the present invention has the following advantages:
The tower direct dry cooling-system of the present invention does not adopt the ridge of NDC or NDACC horizontally disposed, but condenser is arranged in the outer border of cooling tower with natural air exhaust in the mode of column, overlook the finned-tube bundle plate, present the Eight characters skewed (Eight characters prefix section's height and the bottom is low).Natural air exhaust, abandon using shutter, antifreeze means be contrary following current arrange, allow condenser top inflation (large condenser is become small condenser to be used), open triangular aslant cover plate (hot blast improvements) and carry additionally the deep bead method of aerofoil (the reference wet cooling tower put into gear).Four kinds of means come into operation one by one or make up and come into operation.
Shutter slightly has certain impact to the cleaning of fin.Annual shutter was harmful within 3/4 period, had increased the resistance that cold wind flows, and had reduced heat transfer efficiency.Therefore, tower direct dry cooling-system does not use shutter, changes the aerofoil of putting into gear.The aerofoil of just putting into gear during preventing freeze in winter.In all the other periods, the aerofoil of then not putting into gear.
Condensate water collecting endless tube and horizontal tube bury in below ground, are used for keeping Land leveling, to make things convenient for hanging and taking and removing of deep bead.
The dual variation of tower direct dry cooling-system energy reform of nature wind and environment temperature, have novel structure and exquisite layout of utilizing natural ventilation system cooling turbine discharge, formed larger heat exchange area, and can get access to more cooling air quantity, do not have old-fashioned ACC system energy consumption---the power consumption of blower fan distribution motivation does not have noise; Cold energy consumption between tower direct dry cooling-system does not have yet---the power consumption of water circulating pump distribution motivation, the cold condenser that is equipped with in steam turbine building between more not having---the 600MW unit is economized 36,000,000 yuan.Tower direct dry cooling-system can obtain lower condenser pressure summer, realizes the low back pressure operation of steam turbine, promotes full sending out.Some direct-cooled advantages of cold-peace between tower direct dry cooling-system is integrated have following 8 advantages:
1, gravity-flow ventilation: utilize the air heat of dry and cold tower to rise floating function, save the axial flow blower of ACC; Be reserved with the adequate condition of " cooling, smoke evacuation, desulfurization " three towers unification.
2, the Eight characters is arranged: windage reduces.Load transfer is to ground: the condenser column is arranged on the ground, the high-altitude load of ACC (mainly being the tube bank deadweight), has transferred to ground, the deadweight of cold heat-exchange working medium (recirculated water) between also not having, and Aseismic Design becomes simply (not comprising cooling tower).Under 1 atmospheric pressure, when steam condensation is water, 1725 times of volume-diminished.The internal capacity of supposing direct air cooled condenser equates with the internal capacity of a cold heat sink, and so, the water in the direct air cooled condenser, vapour add up to weight, only be between in the cold heat sink water heavy 5/10000ths. eight.
3, the standpipe self-supporting: the enabling capabilities of standpipe is the several times of horizontal tube (be 2 times such as the DN300 pipes, along with the increase of caliber, multiple also increases).Take full advantage of DN2000, DN1000 tubing string at pressurized, turned round and all directions are subjected to excellent performance aspect curved.
4, cross is every wind: the crosswise wind isolation board is arranged in the tower, can eliminate draught.
5, heat-transfer surface increases: have the condition that improves tube bank wing ratio, can significantly increase heat-sinking capability;
6, cold blast rate is large: windage is little and cause air quantity large.
7, freeze proof measure: but the 1. ratio of Set arbitrarily adverse current, following current tube bank; 2. reduce and bleed, allow condenser top gassy, be equivalent to that a large condenser is become small condenser and use; 3. open the triangular aslant cover plate, hot blast gets warm again after a cold spell; 4. the aerofoil of putting into gear reduces cooling air quantity.
8, without separation valve door, vapour locking reduces on the blow-off line.
Initial estimate adopts the comparable ACC of tower direct dry cooling-system system to increase by 3% electricity volume.
Description of drawings
Fig. 1 is the schematic diagram of the direct dry cooling systems ACC of classics; A condensing and cooling unit have been drawn among the figure; The Turbo-generator Set of 600MW generally has 56 unit.
Fig. 2 is the schematic diagram of system of the present invention; Drawn 3 identical condensings and cooling unit among the figure, the finned-tube bundle plate of unit, the left and right sides is reduced to tabular drafting; In order to give top priority to what is the most important, do not draw the oblique bridging piece of armored concrete at cooling tower ring beam place.
Fig. 3 be system of the present invention along the profile of A-A line among Fig. 4, wherein α is 30~60 °; In order clearly to represent critical piece, do not draw the pillar of cooling tower among the figure.
Fig. 4 is that system of the present invention is along the cutaway view of B-B line among Fig. 3, in order clearly to represent the column condenser, there is the underground condensate water collecting endless tube in 1/4 tower district not have drawn, the cross wind isolation board is arranged in the tower, can eliminate draught, wind isolation board is reinforced concrete prefabricated board, highly is not less than the tower direct air cooled condenser of the present invention.
Fig. 5 a is the structural representation of the present invention that is provided with barge board, oblique bridging piece and triangular aslant cover plate, has only drawn the deep bead in 1/4 tower district; Fig. 5 b is the partial enlarged drawing of Fig. 5 a, has illustrated the hook pattern of deep bead, and every deep bead has 4 hooks; Cold flat bridging piece changes the oblique bridging piece of armored concrete between the present invention's handle, in order to hold huge scroll casing shape steam-distributing pipe, arrow represents that cold wind skims over the situation of finned-tube bundle plate among the figure.
Fig. 6 is for being used for expressing the schematic diagram of system of the present invention scroll casing shape steam distribution pipeline and column condenser; 30~60 ° of α, 10 times of calculating in cold water pipe cross section have Dmax3.16d between getting spiral case pipe starting point place tube section and being; To the 600MW unit, cold d=3m between employing adopts tower directly dry and coldly, and then spiral case pipe maximum gauge is Dmax9.48m.
Fig. 7 is similar to Fig. 4, is used for expressing system of the present invention 2 semi-scroll shellies steam-distributing pipe road, to 600MW unit, Dmax2.236d=6.7m.
The figure elements instruction card
Modular member 3,4,8 purpose: be convenient to the factory floor manufacturing, be convenient to building-site welding inside weld (caliber is too small, can't do inseam).
The specific embodiment
See also Fig. 2 to shown in Figure 7, a kind of tower direct air cooled condenser of the present invention comprises scroll casing shape steam distribution main 2 and condensing unit.Condensing unit comprises that standpipe, following current tube bank 5, adverse current tube bank 6 and adverse current following current distribute inclined clapboard 16.Standpipe comprises joins vapour standpipe 3 and discharge 4, joins the adverse current following current is installed between vapour standpipe 3 and the discharge 4 distributes inclined clapboard 16, joins that vapour standpipe 3 and discharge 4 vertically arrange and discharge 4 is positioned at and joins vapour standpipe 3 tops.Above-mentioned standpipe tilts first row tube bank and second row tube bank is installed downwards, the skewed layout of the Eight characters that first row tube bank and second row tube bank consist of.The first row tube bank comprises a plurality of following current tube bank 5 and a plurality of adverse current tube banks 6 that are installed on the discharge 4 of joining on the vapour standpipe 3 that are installed on; The tube bank of the second comb is arranged symmetrically with the first row tube bank.Following current tube bank 5 is restrained 6 parallel and interval settings with adverse current, and the end under the following current tube bank 5 of same row and adverse current tube bank 6 are tilted to all is connected to a condensate water collecting standpipe 8.Angle between following current tube bank 5 and adverse current tube bank 6 and the horizontal plane is α=30~60 °.Adjacent condensing unit shares a condensate water collecting standpipe 8.The ratio of distributing inclined clapboard 16 can adjust arbitrarily and distribute adverse current and following current condenser by adjusting the adverse current following current.First row tube bank and the second row tube bank Eight characters are arranged: windage reduces, load transfer is to ground: the condenser column is arranged on the ground, the high-altitude load of ACC (mainly being the tube bank deadweight), transferred to ground, the deadweight of cold heat-exchange working medium (recirculated water) between also not having, Aseismic Design becomes simply (not comprising cooling tower); Under 1 atmospheric pressure, when steam condensation is water, 1725 times of volume-diminished.The internal capacity of supposing condenser of the present invention equates with the internal capacity of a cold heat sink, and so, the water in the condenser of the present invention, vapour add up to weight, only be between in the cold heat sink water heavy 5/10000ths. eight.
Join vapour standpipe 3 and adopt the standpipe self-supportings: the enabling capabilities of standpipe is the several times of horizontal tube (be 2 times such as the DN300 pipes, along with the increase of caliber, multiple also increases).Take full advantage of DN2000, DN1000 tubing string at pressurized, turned round and all directions are subjected to excellent performance aspect curved.
Exhaust steam flows in the scroll casing shape steam distribution main 2 by the steam discharge main, enters and joins in the vapour standpipe 3, is condensed into water through following current tube bank 5, flows in the collecting pipe 8; Through a small amount of steam that not yet condenses after the following current tube bank 5, rise to the top of collecting pipe 8, be condensed into water through adverse current tube bank 6; Other gas such as not condensing vapour and leaked-in air etc. of minute quantity is collected in the discharge 4, is pumped by vacuum-pumping pipeline 13.When steam condensation was water, volume was rapid little over thousands of times and form vacuum.Collecting pipe 8 connects buried receipts condensate water collection endless tube 17, and buried receipts condensate water collection endless tube 17 is by going condensate tank carrier pipe 170 that the condensate water of collecting is delivered to condensate tank 9.Condensate tank 9 connects scroll casing shape steam distribution main 2 by drainage pump 12, and condensate tank 9 also is connected with condensate pump 11.Vacuum-pumping pipeline 13 connects scroll casing shape steam distribution main 2, and connects condensate tank 9 by liquid-ring type vacuum pumping pump 10.
A kind of tower direct dry cooling-system of the present invention comprises tower direct air cooled condenser; Tower direct air cooled condenser is arranged at armored concrete hyperbolic-type cooling tower 15 bottoms, a plurality of condensing units are circular layout, the vapour standpipe 3 of joining of a plurality of condensing units all connects scroll casing shape steam distribution main 2, and the discharge 4 of a plurality of condensing units all connects vacuum-pumping pipeline 13.Armored concrete hyperbolic-type cooling tower 15 inside are provided with the crosswise wind isolation board, can eliminate draught.
See also shown in Fig. 5 a and Fig. 5 b, the top of tower direct air cooled condenser is provided with the oblique bridging piece 20 of armored concrete at the cooling tower ring beam place; Collecting pipe 8 both sides respectively are provided with two hooks, glass fiber reinforced plastic wind deflector 19 can be hung between two collecting pipes 8 by hook.Be stamped triangular aslant cover plate 21 on the two comb bundles of adjacent condensing unit.
See also Fig. 4 and shown in Figure 7, scroll casing shape steam distribution main 2 can be such as the monolithic construction among Fig. 4 among the present invention, also can adopt the Split type structure of the symmetry shown in Fig. 7.The top of scroll casing shape steam distribution main 2 reduces gradually to terminal internal diameter.
Power Plant varies in size, and causes tower direct dry cooling-system scale different.The first power plant, two embodiments of second power plant are arranged.
One, but the embodiment of a 66OMW Turbo-generator Set of the first power plant is as follows:
Two, the embodiment of second power plant 0.3MW unit is as follows:
Second power plant 0.3MW unit and the public wet cooling tower of other 5 units are separated, and clammyly change tower direct dry cooling-system, and tower direct dry cooling-system is carried out the industrialness checking.Clammy tower and all the other units are maintained the statusquo, and do not make any changes.
By enlarging the scale of tower direct dry cooling-system, tower direct dry cooling-system can be complementary with wet cooling gas turbine, and this need not transform steam turbine.
Tower direct dry cooling-system is designed with wind isolation board in tower, the surrounding air flow field is not had special requirement.According to the present situation of second power plant, dry and cold tower is arranged in the steam turbine building stiff end, about 50 meters far away apart from steam turbine.
From the exhaust steam that steam turbine is discharged, draw main building by the pipeline of DN3000, arrive the outer scroll casing shape main steam range of cooling tower, enter respectively the steam distribution pipe of 12 DN2000, to the bank of condenser pipes distributing steam.Because the project location lowest temperature is 30 ℃, condenser adverse current section area is 20% of the gross area, and condenser is arranged in the cooling tower border, height 6m, width 6m.Adopt 3 combs, finned tube is that steel rolls constructed of aluminium, and the steel pipe specification is D25 * 1.5mm, and the fin specification is D57/D25mm, and sheet is thick to be 0.30mm, spacing of fin 2.3mm.
Tower direct dry cooling-system calculates and the configuration list
Sequence number |
Project |
Tower is arranged vertically outward |
1 |
Completely send out summer temperature (℃) |
30 |
2 |
Full carbuncle on the back pressure [kPa(a)] |
18 |
3 |
Design temperature (℃) |
20 |
4 |
Design back-pressure [kPa(a)] |
10.8 |
5 |
Air side film-cooled heat (m
2)
|
36000 |
6 |
Steam side condensation area (ten thousand m
2)
|
1352 |
7 |
Windward side area (m
2)
|
360 |
8 |
Windward side wind speed (m/s) |
1.68 |
9 |
Pillar condenser number (individual) |
12 |
10 |
Dry and cold tower border pillar condenser outside diameter (m) |
31 |
11 |
Triangular aslant cover plate perpendicular bisector length (m) |
6.96 |
12 |
0 meter absolute altitude place of cooling tower diameter (m) |
13 |
13 |
Cooling tower height (m) |
78 |
14 |
Cooling tower air inlet height (m) |
6.5 |
15 |
Tiltedly bridging piece width (plagioclase) (m) |
1.15 |
Design data sheet (declared working condition)
Second power plant 0.3MW Transformation of Unit is the advantage of tower direct dry cooling-system:
(1) tower direct dry cooling-system natural air exhaust effect of hot-air in the cold tower cylinder between having used has realized the heating power automatic cycle of cooling-air.Not only save the High Altitude Platform of direct air cooling system and supporting frame, also saved all investments of whole axial fan systems, more do not have blower fan power consumption, maintenance cost and noise, simultaneously eliminated also that fan system brings all faults of influential Unit Economic and safe operation.
Tower direct dry cooling-system has been used the advantage that the direct steam discharge of steam turbine enters ACC.Do not have the armamentarium of the interior condenser of a cooling system steam turbine building and terminal temperature difference loss and circulation, without power consumption, noise and occupation of land, reduce investment outlay.All faults that affect Unit Economic and safe operation that these equipment bring have also been eliminated simultaneously.
Tower direct dry cooling-system has only just been passed to air with heat through a partition heat exchange, and heat transfer temperature loss is little, and logarithmic mean temperature difference (LMTD) is large, is conducive to reduce the operation back pressure of steam turbine.Adopt and a cold same air mass flow, can take away more heat, make the steam turbine back pressure fall cold lowlyer than between, thereby increase the power output of steam turbine.
Tower direct dry cooling-system has thoroughly solved the distinctive hot air circulation problem of ACC.
Summer condensate water temperature than 70 ℃ of ACC low 15 ℃, than cold 65 ℃ also low 10 ℃; The deironing amount of condensate polishing system is little, thereby reduces cost.
Second power plant 0.3MW steam turbine is clammy change tower direct dry cooling-system dry and cold after, strengthen cooling air quantity 50%, the finned tube gross area is 36000m
2(the ACC area significantly increases relatively), cooling effect is good.When 20 ℃ of temperature, tower direct dry cooling-system can guarantee that the steam turbine back pressure reaches 10.8kPa, makes steam turbine with near the operation of clammy operating mode, under the constant condition of throttle flow, only reduces generated energy 18kW.
Tower direct dry cooling-system power consumption only has vavuum pump power consumption 20kW, condensate pump power consumption 11kW, under 20 ℃ of temperature conditions, not only per hour economize on water 18 tons, also than present clammy economize on electricity 72kW, than a cold economize on electricity 342kW, than direct-cooled economize on electricity 362kW, the tower direct dry cooling-system gross investment of second power plant is about 6,000,000 yuan, 10 years can realize repaying capital with interest (having considered other 5 super electricity amounts of unit cooling system grow during estimation).