A kind of overcritical Direct Air-Cooled heat supply unit heat supply network draining system
Technical field
The utility model relates to a kind of heat supply unit heat supply network draining system, particularly relates to a kind of overcritical Direct Air-Cooled heat supply unit heat supply network draining system.
Background technology
Present large-scale heat supply power plant usually adopts the heat-supplying mode of extracting Steam Heating heat supply network recirculated water from steam turbine out, and steam heats in heat exchangers for district heating and condenses into that hydrophobic to return Steam Turbine Regenerative System recycling behind the heat supply network recirculated water; Exist the problem that heat supply network drain water quality that reason such as heat exchangers for district heating pipe side leakage causes descends.A kind of heat supply network draining system that present large-scale heating power plant generally adopts, the steam of releasing from steam turbine condenses into hydrophobic after having heated heat supply network recirculated water in the middle of the heat exchangers for district heating, after the heat supply network drainage pump boosts, deliver to oxygen-eliminating device then, after the feed water system of boiler to deliver to boiler recycling.Above-mentioned heat supply network draining system reclaim heat supply network hydrophobic the time also with the hydrophobic feed water system of boiler of bringing into of contaminated heat supply network.
For subcritical dum boiler, because boiler is provided with continuous blowdown and periodical blowdown system, the water pollution issue of above-mentioned heat supply network draining system can solve by boiler blow-off.But along with the development and the maturation of China's thermal power generating technology, overcritical or ultra supercritical machine consists of the development trend of fired power generating unit, and increasing from now on heat supply power plant will select supercritical unit for use.For supercritical once-through boiler, because direct current cooker is not provided with drainage, there is the hydrophobic problem that directly enters boiler without the condensate water precision processing of contaminated heat supply network in existing heat supply network draining system, promptly this system can not satisfy " the whole feedwater that enter direct current cooker all should handle through 100% desalination " requirement, have the possibility that jeopardizes super critical boiler and steam turbine safe and stable operation.Therefore for satisfying the water quality requirement of direct current cooker, must after handling, the polishing unit that condenses just can send into boiler with contaminated heat supply network is hydrophobic.
Solving the most direct thinking of problem noted earlier is to utilize the polishing unit processing heat supply network that condenses that generally is provided with in the middle of the power plant condensate system hydrophobic, it is reached send into boiler after super critical boiler is given water quality standard; But the general hydrophobic condensate system of directly sending into of the heat supply network between 138~162 ℃ of temperature, the damage of " resin-oatmeal " in the polishing unit that can cause condensing.For addressing this problem, must manage to reduce the heat supply network drain temperature that enters the polishing unit that condenses.
The utility model content
The purpose of this utility model is to provide a kind of overcritical Direct Air-Cooled heat supply unit heat supply network draining system with low cost, effective.Reach the purpose that reduces the heat supply network drain temperature by heat supply network drain cooler unit is set, make the heat supply network draining system can reclaim working medium, also can make the quality of the working medium that reclaims satisfy the feedwater water quality requirement of direct current cooker.
The purpose of this utility model is implemented by following technical scheme, a kind of overcritical Direct Air-Cooled heat supply unit heat supply network draining system, comprise the hydrophobic piping of heat supply network, the heat supply network circulating water piping, condensate water piping and oxygen-eliminating device, the hydrophobic piping of described heat supply network comprises heat exchangers for district heating and steam exhaust device, described condensate water piping comprises the polishing unit that condenses, the hydrophobic piping of described heat supply network also includes heat supply network drain cooler unit, the described heat exchangers for district heating that described heat supply network drain pipe is fastened, described heat supply network drain cooler unit and described steam exhaust device are communicated with successively, described steam exhaust device is communicated with the described polishing unit that condenses of described condensate water piping, the described polishing unit that condenses is communicated with described oxygen-eliminating device, the heat supply network recirculated water backwater end of described heat supply network circulating water piping is connected with the heat supply network recirculated water arrival end of described heat exchangers for district heating with described heat supply network drain cooler unit respectively, and the heat supply network circulating water outlet end of described heat exchangers for district heating and described heat supply network drain cooler unit supplies water to hold with the heat supply network recirculated water of described heat supply network circulating water piping and is connected.
The heat supply network recirculated water backwater end of described heat supply network circulating water piping can also be connected with the heat supply network recirculated water arrival end of described heat exchangers for district heating, the heat supply network circulating water outlet end of described heat exchangers for district heating is connected with the heat supply network recirculated water arrival end of described heat supply network drain cooler unit, and the heat supply network circulating water outlet end of described heat supply network drain cooler unit supplies water to hold with the heat supply network recirculated water of described heat supply network circulating water piping and is connected.
Described heat supply network drain cooler unit comprises at least one or an above heat supply network drain cooler.
Extracted steam from turbine through heat exchangers for district heating be cooled to from the heat supply network recirculated water heat exchange of heat supply network circulating water piping hydrophobic after, enter heat supply network drain cooler unit; Hydrophobicly in heat supply network drain cooler unit, further be cooled to 80 ℃ or be lower than 80 ℃ with heat supply network recirculated water heat exchange from heat supply network circulating water piping or heat exchangers for district heating, certainly flow into steam exhaust device by intrasystem pressure reduction, carry out entering oxygen-eliminating device behind 100% desalination through the polishing unit that condenses again, enter the super critical boiler water supply system at last.
Advantage of the present utility model is that (1) the utility model has solved the hydrophobic problem of carrying out water treatment of heat supply network by very simple, easy-operating heat supply network drain cooler unit is set; (2) the utility model is not provided with heat supply network drainage pump unit, and hydrophobic to reclaim heat exchangers for district heating hydrophobic from flowing to steam exhaust device, reduces station service, energy savings; (3) adopted simple technological means, with low cost, workable, economic benefit is high.
Description of drawings
Fig. 1 is subcritical and following parameter Direct Air-Cooled heat supply unit heat supply network draining system schematic diagram.
Fig. 2 is embodiment 1 an overcritical Direct Air-Cooled heat supply unit heat supply network draining system schematic diagram.
Fig. 3 is embodiment 2 overcritical Direct Air-Cooled heat supply unit heat supply network draining system schematic diagrames.
The hydrophobic piping 1 of heat supply network, heat supply network circulating water piping 2, condensate water piping 3, oxygen-eliminating device 4, heat exchangers for district heating 5, heat supply network drain cooler unit 6, steam exhaust device 7, the polishing unit 8 that condenses, steam turbine 9.
The specific embodiment
Embodiment 1: a kind of overcritical Direct Air-Cooled heat supply unit heat supply network draining system, comprise the hydrophobic piping 1 of heat supply network, heat supply network circulating water piping 2, condensate water piping 3 and oxygen-eliminating device 4, the hydrophobic piping 1 of heat supply network comprises heat exchangers for district heating 5 and steam exhaust device 7, condensate water piping 3 comprises the polishing unit 8 that condenses, the hydrophobic piping 1 of heat supply network also includes heat supply network drain cooler unit 6, heat exchangers for district heating 5 on the hydrophobic piping 1 of heat supply network, heat supply network drain cooler unit 6 and steam exhaust device 7 are communicated with successively, steam exhaust device 7 is communicated with the polishing unit 8 that condenses of condensate water piping 3, the polishing unit 8 that condenses is communicated with oxygen-eliminating device 4, the heat supply network recirculated water backwater end A of heat supply network circulating water piping 2 is connected with D with the heat supply network recirculated water arrival end C of heat exchangers for district heating 5 and heat supply network drain cooler unit 6 respectively, and the heat supply network circulating water outlet end E of heat exchangers for district heating 5 and heat supply network drain cooler unit 6 supplies water with the heat supply network recirculated water of heat supply network circulating water piping 2 with F and holds B to be connected.Steam turbine 9 draw gas through heat exchangers for district heating 5 and heat supply network recirculated water heat exchange from heat supply network circulating water piping 2 be cooled to hydrophobic after, enter heat supply network drain cooler unit 6; Hydrophobicly in heat supply network drain cooler unit 6, further be cooled to 80 ℃ or be lower than 80 ℃ with heat supply network recirculated water heat exchange from heat supply network circulating water piping 2, certainly flow into steam exhaust device 7 by intrasystem pressure reduction, after the polishing unit 8 that condenses carries out 100% desalination, enter oxygen-eliminating device 4 again, enter the super critical boiler water supply system at last.
Heat supply network drain cooler unit 6 comprises a heat supply network drain cooler.
Embodiment 2: a kind of overcritical Direct Air-Cooled heat supply unit heat supply network draining system, comprise the hydrophobic piping 1 of heat supply network, heat supply network circulating water piping 2, condensate water piping 3 and oxygen-eliminating device 4, the hydrophobic piping 1 of heat supply network comprises heat exchangers for district heating 5 and steam exhaust device 7, condensate water piping 3 comprises the polishing unit 8 that condenses, the hydrophobic piping 1 of heat supply network also includes heat supply network drain cooler unit 6, heat exchangers for district heating 5 on the hydrophobic piping 1 of heat supply network, heat supply network drain cooler unit 6 and steam exhaust device 7 are communicated with successively, steam exhaust device 7 is communicated with the polishing unit 8 that condenses of condensate water piping 3, the polishing unit 8 that condenses is communicated with oxygen-eliminating device 4, the heat supply network recirculated water backwater end A of heat supply network circulating water piping 2 is connected with the heat supply network recirculated water arrival end C of heat exchangers for district heating 5, the heat supply network circulating water outlet end E of heat exchangers for district heating 5 is connected with the heat supply network recirculated water arrival end D of heat supply network drain cooler unit 6, and the heat supply network circulating water outlet end F of heat supply network drain cooler unit 6 supplies water with the heat supply network recirculated water of heat supply network circulating water piping 2 and holds B to be connected.Steam turbine 9 draw gas through heat exchangers for district heating 5 and heat supply network recirculated water heat exchange from heat supply network circulating water piping 2 be cooled to hydrophobic after, enter heat supply network drain cooler unit 6; Hydrophobicly in heat supply network drain cooler unit 6, further be cooled to 80 ℃ or be lower than 80 ℃ with heat supply network recirculated water heat exchange from heat exchangers for district heating 5, certainly flow into steam exhaust device 7 by intrasystem pressure reduction, after the polishing unit 8 that condenses carries out 100% desalination, enter oxygen-eliminating device 4 again, enter the super critical boiler water supply system at last.
Heat supply network drain cooler unit 6 comprises two heat supply network drain coolers.