Background technology
In the fields such as the energy, electric power, chemical industry, iron and steel, pharmacy, there are many production links must cool guarantee production process continuous and steady operation in time.
For thermal power generation, the cooling of the steam discharge of steam turbine is become condensate water and is not only vital process in Steam Power Circulation, and the effect (cooldown rate, exothermic temperature) of cooling also can affect the efficiency of power cycle.Good cooling can improve the energy utilization rate of thermal power generation, realizes the energy-saving and emission-reduction of power generation.
Tradition thermoelectricity adopts clammy mode, turbine discharge by surface condenser by heat dissipation to recirculated cooling water, absorb the recirculated cooling water after heat and send into wet cooling tower, directly to contact with air at Ta Nei and carry out heat convection and evaporation and heat-exchange, realize the cooling of recirculated cooling water.It is can by below circulating water to air dry-bulb temperature that wet type cools the remarkable advantage had, close to air ' s wet bulb temperature.Because the evaporation of recirculated cooling water self and air carry the reasons such as water droplet, recirculated cooling water has certain loss in cooling procedure, needs lasting moisturizing.In addition, wet cooling tower outlet air is in saturation state, moisture can be caused to separate out as mixed with cool ambient air, produces water smoke, has a negative impact to surrounding environment.
Along with the scarcity day by day of water resource, adopt traditional thermoelectricity of clammy mode, because it needs consume great lot of water resources and be faced with severe challenge to factors such as environment have a negative impact in running.In the three northern areas of China of the few water of the rich coal of China, be objectively difficult to the water resources quantity fully ensured needed for clammy generating.Compare clammy generating, use air and gas turbine exhaust gas or between air and recirculated cooling water, air cooling (dry and cold) generation technology of different transfer of heat obtains increasingly extensive application in recent years.
Air cooling system mainly contains three kinds: the indirect air cooling system (Harmon formula system) of direct air cooling system, belt surface formula condenser and the indirect air cooling system (Hai Leshi system) of band injecting type (hybrid) condenser.In direct air cooling system, heat is directly discharged in surrounding air by finned tube exchanger by gas turbine exhaust gas, does not need recirculated cooling water; In indirect air cooling system, recirculated cooling water is
independentclosed system, recirculated water loss seldom, does not need to supplement substantially.
Although air cooling system has the remarkable advantage of saving water resource, also there is intrinsic shortcoming in it.In direct air cooling system, need the generated energy consuming power plant 1% ~ 1.5% for driving diameter fan that fin outer tube air flows, and produce noise.In Harmon formula indirect cooling system, recirculated cooling water needs through twice heat exchange, and heat-transfer effect is poor, and under identical design temperature condition, turbine back pressure is higher, and unit economy is low.Hai Leshi indirect cooling system adopts direct-contact type condenser, and equipment is numerous, system complex, and needs a large amount of precision processing water, and water treatment costly.In summer, when the dry-bulb temperature of surrounding air is higher, above-mentioned three kinds of heat transfer temperature differences between air cooling system and surrounding air reduce, and cause turbine back pressure in power plant to raise, unit economy declines.
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countryunder calling energy-saving and emission-reduction, the overall background of building a resource-conserving society energetically, in the production process in the fields such as the energy, electric power, chemical industry, realize high efficiency cooling and can significantly improve efficiency of energy utilization, save the valuable source such as water, electricity.The present invention is on existing dry and cold and clammy basis, and comprehensively both advantage, has developed
novelassociating cooling system.
Summary of the invention
In order to overcome the deficiencies in the prior art, the invention provides a kind of dry wet associating cooling tower and the application thereof that adopt gravity-flow ventilation and combined running pattern, concrete technical scheme is as follows:
Adopt the dry wet associating cooling tower of gravity-flow ventilation and combined running pattern, comprise tower body 1, supporting construction 15, dry and cold section, clammy section and flow distributing system; Tower body 1 adopts hyp form, is supported on ground by supporting construction 15; Supporting construction 15 is " X " type post or " people " font post; Dry and cold section and clammy section is vertically integratedly arranged in same cooling tower; Dry and cold section is positioned at the top of clammy section;
Described dry and cold section comprises cooling triangle 2 and dry and cold section of shutter 3; Cooling triangle 2 is as heat-exchanger rig, be made up of each other in 30 ° ~ 120 ° two vertical air cooled fin tube bundles, 100 ~ 2000 cooling triangle 2 unit are arranged around tower outside Ta Nei or tower for one week, and dry and cold section of shutter 3 is along the circumferential direction arranged in cooling triangle 2 periphery, as air intake; The setting height(from bottom) of dry and cold section of equipment is higher than the height of dry and cold section of equipment in traditional indirect air cooling;
Described clammy section comprises dehydrater 4, water distribution system 5, packing area 6, collecting-tank 8 and clammy section of shutter 16; Water distribution system 5 is by cool water shower to packing area 6, and cooling water is introduced in collecting-tank 8 behind packing area 6 with air heat-exchange; Clammy section of air, by entering packing area 6 after clammy section of shutter 16, absorbs the air after heat and moisture and imports in cooling tower, form suction force upwards;
Described flow distributing system comprises general import pipeline 17, general export pipeline 18, dry and cold section of inlet pipeline 19, dry and cold section of outlet conduit 20, clammy section of inlet pipeline 21, clammy section of outlet conduit 22, the connecting pipe 23 of dry and cold section of outlet and clammy section of import, valve A ~ valve E (9 ~ 13) and circulating pump 14; Mounted valve A on dry and cold section of inlet pipeline 19, mounted valve D on dry and cold section of outlet conduit 20, dry and cold section of outlet and mounted valve B in the connecting pipe 23 of clammy section of import, mounted valve C on clammy section of inlet pipeline 21, mounted valve E on clammy section of outlet conduit 22, general export pipeline 18 is installed circulating pump 14.
Further, described clammy section comprises reverse-flow and cross-flow type two kinds of arrangements.
When adopting reverse-flow clammy section, in the composition of clammy section, also comprise rain belt 7; The locations of structures of reverse-flow clammy section is followed successively by dehydrater 4, water distribution system 5, packing area 6, rain belt 7, clammy section of shutter 16 and collecting-tank 8 from top to bottom; Spray equipment in dehydrater 4, water distribution system 5 and the filler in packing area 6 horizontally disposed in tower; Described filler is even or nonuniform mutation operator; Supporting construction 15 is as air intake.
When adopting clammy section of cross-flow type, collecting-tank 8 is positioned at tower bottom, and dehydrater 4 is vertically arranged at tower edge, the filler in the distribution reservoir in water distribution system 5 and packing area 6 tower edge or tower outer horizontally disposed; Described filler is even or nonuniform mutation operator; Clammy section of shutter 16 is as air intake.
Dry and cold section is positioned at clammy section of top, is connected between the two by flow distributing system; The dry and cold section of air-recirculated water heat exchange mode for heat exchangers such as use finned tubes, clammy section is heat convection and vapor cooling system.Distance between dry and cold section and clammy section, cooling water flow can be chosen according to actual conditions such as local meteorological conditions.
The dry wet application of associating cooling tower in cooling as above.
The air cooled fin tube bundle of dry and cold section, pipe internal flow is water, and managing fluid between outer fin is air, and under the swabbing action that free convection produces in cooling tower, air flows through air cooled fin tube bundle from bottom to top, is passed by water side heat and takes away; Dry and cold section of shutter 3 of cooling triangle 2 periphery is for controlling air side air intake.
In reverse-flow clammy section, water effluent moves as from top to down successively through water distribution system 5, packing area 6 and rain belt 7, wherein, water distribution system 5 by cool water shower to packing area 6, cooling water completes the heat and mass with air in packing area 6 and rain belt 7, finally arrives collecting-tank 8 and mixes; Air side flow is for entering in tower from tower is outer by supporting construction 15, after clammy section of shutter 16, rising of being heated in rain belt 7, successively by rain belt 7, packing area 6, water distribution system 5 and dehydrater 4, arrive dry and cold fragment position, with flow through this be in dry and cold section absorb heat after hot-air mix.
In clammy section of cross-flow type, water effluent moves as from top to down successively through water distribution system 5 and packing area 6, and water distribution system 5 is by cool water shower to packing area 6, and cooling water completes the heat and mass with air in packing area 6, finally arrives collecting-tank 8 and mixes; Air side flow is for entering packing area 6 from tower is outer by clammy section of shutter 16, carry out contacting heat convection with recirculated water or recirculated cooling water, enter in tower by dehydrater 4 and supporting construction 15 subsequently, rise to dry and cold fragment position, and flow through this and be in the dry and cold section of hot-air absorbing heat and mix.
The aqueous water carried secretly in Hot wet air heating is collected in the effect of dehydrater 4, introduces collecting-tank 8, to reach the object of water saving.
Further, according to thermic load and Meteorological Elements in China, dry and cold section with clammy section of adverse current or flow over clammy section and adopt a pair cooling water of following combined running mode to cool:
A) all cooling water first through dry and cold section, after through the series operation mode of clammy section---now, in flow distributing system, valve A, valve B and valve E are in full-gear, valve C and valve D is in buttoned-up status, and dry and cold section of shutter 3 and clammy section of shutter 16 are in open mode;
B) cooling water is distinguished by a certain percentage
independentthrough dry and cold section and clammy section parallel running mode---now, in flow distributing system, valve A, valve C, valve D and valve E are in open mode, and valve B is in buttoned-up status, dry and cold section of shutter 3 and clammy section of shutter 16 are in open mode;
C) whole cooling water is first through dry and cold section, rear portion through clammy section, the mixed flow method of operation of the direct backwater of another part---now, in flow distributing system, valve A and valve E is in full-gear, valve C is in buttoned-up status, valve B and valve D is in certain aperture state, and dry and cold section of shutter 3 and clammy section of shutter 16 are in open mode;
D) cooling water is first distinguished by a certain percentage
independentthrough dry and cold section and clammy section, the cooling water wherein flowing through dry and cold section flows through the mixed flow method of operation of clammy section again---now, in flow distributing system, valve B and valve E is in full-gear, valve D is in buttoned-up status, valve A and valve C is in certain aperture state, and dry and cold section of shutter 3 and clammy section of shutter 16 are in open mode.
In thermic load during lower or system overhaul, dry and cold section and clammy section also can isolated operation.When dry and cold section or clammy section of isolated operation mode, cooling water and cooling-air are merely through one of dry and cold section and clammy section, and another section is in buttoned-up status.Separately during dry and cold section of operation, in flow distributing system, valve A and valve D is in full-gear, and valve B, valve C and valve E are in buttoned-up status, and dry and cold section of shutter 3 is in open mode; Adopt independent clammy time, in flow distributing system, valve C and valve E is in full-gear, and valve A, valve B and valve D are in buttoned-up status, and clammy section of shutter 16 is in open mode.
Of the present invention is a kind ofly adopt natural ventilation system, cooling tower for reducing circulating water temperature, cooling tower is final cooling medium with surrounding air, integrated use different transfer of heat (dry and cold) and evaporative cooling (clammy) two kinds of types of cooling in tower, in conjunction with Practical Meteorological Requirements condition, adopt the combined running pattern of series, parallel or mixture length, not only can economize on water but also lower outlet water temperature can be provided when summer high temperature, may be used in the fields such as the energy, electric power, chemical industry, iron and steel, pharmacy.Beneficial effect of the present invention is:
(1) use Double curve tower-shape, rely on Effect of Nature Convection, suction force can be formed at tower upper and lower, drive air flowing without the need to blower fan, save a large amount of electric energy;
(2) adopt dry, the clammy section of mode being vertically arranged in same cooling tower up and down, make full use of space in tower;
(3) dry, clammy section of combined layout mode is adopted, make in a tower, there are upper and lower two place's thermals source, enhance free convection and suction force thereof, under the requirement that required suction force is certain, the height of tower and the diameter of tower can be reduced, reduce the floor space of tower, reduce the initial costs such as the capital construction cost of tower;
(4) adopt dry, clammy section of cooperation, make water be sidelong heat and increase, lower outlet water temperature can be provided, reduce power plant steam turbine back pressure, improve generating efficiency;
(5) be arranged in clammy section of top by dry and cold section, dry and cold section of outlet dry air export mix close to saturated humid air with clammy section, and the rear air humidity reduction of mixing, avoids cooling tower outlet to be atomized, reduce cooling tower surrounding environment influence;
(6) dry and cold section is run throughout the year, enables clammy section carry out associating cooling when environment temperature is too high, can reduce water evaporation loss clammy in running in year, and the year saving recirculated cooling water runs rate of water make-up;
(7) adopt flow distributing system to regulate dry, clammy section operational mode, make cooling tower to the strong adaptability of various Meteorological Elements in China, region is suitable for wider;
(8) can dry and cold section or clammy section of isolated operation when safeguarding, avoid cooling tower to stop transport completely causing to produce interrupting, reduce the economic loss of stopping transport.