A kind of desulfurization cooling potentiation and the system and method for heat recovery
Technical field
The invention belongs to industrial waste gas purifying environmental protection and energy field are and in particular to coal fired power plant flue gas desulfurization device, special
It is not related to the system and method for a kind of desulfurization cooling potentiation and heat recovery.
Background technology
Using coal as the energy, coal combustion produces a large amount of SO in process of production for coal-burning power plant2, for controlling SO2Realize SO2
Qualified discharge, coal-burning power plant's commonly used Gypsum Wet technology carries out flue gas desulfurization.
Wet desulfurization of flue gas by limestone-gypsum method technology adopts cheap limestone as desulfurization absorbent, and limestone is through broken
Breakdown mill powdering and water mix and blend make absorption serosity;Then, in desulfurizing tower, absorb serosity and contact with flue gas adverse current, cigarette
SO in gas2With the CaCO in serosity3Reaction removing SO2, desulfurization product occurs anti-in desulfurization tower bottom and the oxidation air being passed through
Should, ultimately generate gypsum by-product;Flue gas after desulfurization sequentially passes through demister and removes droplet, after flue gas heat-exchange unit heat temperature raising
Through smoke stack emission.Wet desulfurization of flue gas by limestone-gypsum method technology has that response speed is fast, desulfuration efficiency is high, stable and reliable operation,
Side-product is easy to the advantages of recycle, and therefore coal-burning power plant is used widely at home.
Wet desulfurization of flue gas by limestone-gypsum method whole process be a flue gas enthalpy be held essentially constant, in flue gas containing wet
Amount is continuously increased until wet flue gas are the process of saturation, and final desulfurizing tower exit gas temperature is down to adiabatic saturation temperature,
Slurry temperature is also accordingly down to same temperature range.In sweetening process, slurry temperature has considerable influence to desulfuration efficiency.Serosity
Temperature is lower, SO2With CaCO3Dissolubility in serosity is bigger, and overall mass transfer coefficient is also bigger, can effectively improve desulfuration efficiency.
No matter but current wet desulfurization of flue gas by limestone-gypsum method adopts single cycle or Two-way Cycle form, its desulfurizing tower exiting flue gas temperature
Degree all between 45 DEG C~55 DEG C, corresponding slurry temperature also between 45 DEG C~55 DEG C, existing Gypsum Wet cigarette
Desulfurization device does not all take appropriate measures reduction slurry temperature to improve desulfuration efficiency further.
Dynamics with country's execution " energy-saving and environmental protection " state basic policy is increasing, to thermal power plant SO2Discharge Deng pollutant carries
Higher requirement, corresponding requirements SO are gone out2Absorption techniqueses should have higher efficiency.Improve desulfurization by reducing slurry temperature
Efficiency, simultaneously to heat recovery, meets the increasingly strict energy-saving and emission-reduction requirement of country, has important application value.
Chinese patent CN1727296A discloses a kind of wet desulfurization of flue gas by limestone-gypsum method device, belong to station boiler,
The flue gas desulfurization device of Industrial Boiler or kiln, solves little the asking of limestone dissolubility present in existing flue gas desulfurization device
Topic.The present invention includes air-introduced machine, flue gas heat-exchange unit, absorption tower, slurry circulating pump, oxidation pond, oxidation fan, lime stone slurry
Tank, limestone slurry liquid pump, limestone powder bin, Gypsum Fibrosum excavationg pump, Gypsum Fibrosum cyclone, belt dewaterer, filtrate water box and filtrate water
Pump.The present invention is by high concentration CO produced by oxygen-enriched combusting2Flue gas activates to lime stone slurry, and lime stone slurry is molten
Solution speed is accelerated, and dissolubility increases, and desulfuration efficiency improves.But the present invention is due to needing by high concentration CO2Improve limestone molten
Xie Du, is only applicable to oxygen-enriched combustion system, cannot apply under conventional coal-fired plant flue gas atmosphere, and only by improving limestone
Dissolubility improves desulfuration efficiency, limited use.In addition, the present invention is also not related to remaining pick up the heat.
Content of the invention
Potentiation and the system and method for heat recovery it is an object of the invention to provide a kind of desulfurization is lowered the temperature, by heat exchange
Reduce desulfurization slurry temperature, thus effectively improving SO2With absorbent CaCO3Dissolubility in the liquid phase, improves mass transfer rate, enters
And effectively improve desulfuration efficiency(Desulfuration efficiency more than 99%), realize flue gas SO2Ultra-clean discharge, simultaneously by waste heat recovery
After carry out Multi-class propagation, effectively improve the heat utilization efficiency of whole therrmodynamic system, on the whole reduce operating cost, realize heating power system
The efficient energy-saving and emission-reducing of system.
To achieve these goals, the present invention adopts the following technical scheme that:
A kind of desulfurization cooling potentiation and the system of heat recovery, described system is single column single cycle wet process of FGD
Cooling potentiation and waste heat recycling system, including desulfurizing tower, wet-type electrostatic defroster, smoke re-heater, chimney, loop slurry
Pump, heat exchanger, cool slurry circulating pump(Or directly utilize the circulation slurry pump of desulfurizing tower), vaporizer, compressor, condenser,
Heating system, fuel dryer system, inlet air of boiler heating system, described desulfurizing tower arranges circulation slurry pump, described desulfurizing tower
Outlet passes sequentially through wet-type electrostatic defroster, smoke re-heater is connected with chimney, and described smoke re-heater is connected with condenser, institute
State condenser to be also connected with described heating system, fuel dryer system, inlet air of boiler heating system respectively, described condenser passes through
Compressor is connected with vaporizer, and described vaporizer is connected with desulfurizing tower by heat exchanger.
Desulfurization cooling potentiation based on said system and the method for heat recovery, the flue gas that boiler is discharged is in desulfurizing tower
Interior SO is carried out by the effect of circulation slurry pump2Purified treatment, from desulfurizing tower discharge purification after flue gas sequentially pass through wet
The demisting of formula electrostatic precipitator, and after the heat effect of smoke re-heater, by smoke stack emission.The higher slurry of temperature in desulfurizing tower
Liquid is first in cool slurry circulating pump(Or directly utilize the circulation slurry pump of desulfurizing tower)In the presence of pass through heat exchanger heat exchange, change
Heat after heat sequentially passes through the heat pump being made up of vaporizer, compressor, condenser and heat is passed to smoke re-heater, confession
Hot systems, fuel dryer system, inlet air of boiler heating system.
In described desulfurizing tower, the pH value of serosity is 4-5.5, and heat exchange rear slurry temperature is 25 DEG C -35 DEG C.
A kind of desulfurization cooling potentiation and the system of heat recovery, described system is single column Two-way Cycle wet process of FGD
Cooling potentiation and waste heat recycling system, including desulfurizing tower, wet-type electrostatic defroster, smoke re-heater, chimney, loop slurry
Pump, heat exchanger, cool slurry circulating pump(Or directly utilize the circulation slurry pump of desulfurizing tower itself), vaporizer, compressor, condensation
Device, heating system, fuel dryer system, inlet air of boiler heating system, upper spraying layer, liquid receptacle, lower spraying layer, serum pot, institute
State desulfurizing tower setting circulation slurry pump, in described desulfurizing tower, be sequentially arranged lower spraying layer, liquid receptacle, upper spraying layer from bottom to top,
Described liquid receptacle is connected with serum pot, and the outlet of described desulfurizing tower passes sequentially through wet-type electrostatic defroster, smoke re-heater and cigarette
Chimney connects, and described smoke re-heater is connected with condenser, described condenser also respectively with described heating system, fuel dryer system
System, inlet air of boiler heating system connect, and described condenser is connected with vaporizer by compressor, and described vaporizer passes through heat exchanger
It is connected with desulfurizing tower.
Desulfurization cooling potentiation based on said system and the method for heat recovery, the flue gas that boiler is discharged is in desulfurizing tower
The interior effect by circulation slurry pump and lower spraying layer carries out SO2Preliminary purification process, the flue gas after preliminary purification is through upper
Spraying layer carries out deep purifying process, and the serosity that upper spraying layer sprays is collected by liquid receptacle and entered serum pot, from desulfurizing tower row
The gas going out sequentially passes through the demisting of wet-type electrostatic defroster, after the heat effect of smoke re-heater, by smoke stack emission.High pH
In value serum pot, the higher serosity of temperature is in cool slurry circulating pump(Or directly utilize the circulation slurry pump of desulfurizing tower itself)'s
Effect is lower to pass through heat exchanger heat exchange, and the heat after heat exchange sequentially passes through the heat pump being made up of vaporizer, compressor, condenser
Heat is passed to smoke re-heater, heating system, fuel dryer system, inlet air of boiler heating system.With the balance of heat,
Whole desulfurization tower bottom low ph value slurry temperature is also gradually reduced.
The pH value of described desulfurizing tower inner bottom part serosity is 4-5.5, and stable rear slurry temperature is 35 DEG C -45 DEG C;Described
Slurry pH value in serum pot is 5.8-6.5, and heat exchange rear slurry temperature is 25 DEG C -35 DEG C.
A kind of desulfurization cooling potentiation and the system of heat recovery, described device is double tower Two-way Cycle wet process of FGD
Desulfurization cooling potentiation and waste heat recycling system, including front desulfurizing tower, rear desulfurizing tower, wet-type electrostatic defroster, flue gas reheat
Device, chimney, circulation slurry pump, heat exchanger, cool slurry circulating pump(Or directly utilize desulfurizing tower circulation slurry pump), vaporizer,
Compressor, condenser, heating system, fuel dryer system, inlet air of boiler heating system, described front desulfurizing tower pass through outlet flue with
Desulfurizing tower connects afterwards, described front desulfurizing tower, rear desulfurizing tower setting circulation slurry pump, and the outlet of described rear desulfurizing tower passes sequentially through wet
It is connected with chimney after formula electrostatic precipitator, smoke re-heater, described smoke re-heater is connected with condenser, described condenser also divides
It is not connected with described heating system, fuel dryer system, inlet air of boiler heating system, described condenser passes through compressor and evaporation
Device connect, described vaporizer through heat exchanger with after desulfurizing tower be connected.
Desulfurization cooling potentiation based on said system and the method for heat recovery, the flue gas that boiler is discharged is in front desulfurization
Carry out SO in tower2Preliminary purification process, after entering afterwards, desulfurizing tower carries out the deep purifying of flue gas, discharges from rear desulfurizing tower
Gas sequentially passes through wet-type electrostatic defroster demisting, and after smoke re-heater heating, by smoke stack emission, temperature in rear desulfurizing tower
Higher serosity is in cool slurry circulating pump(Or directly utilize desulfurizing tower circulation slurry pump)In the presence of pass through heat exchanger heat exchange,
Heat after heat exchange sequentially pass through the heat pump being made up of vaporizer, compressor, condenser by heat pass to smoke re-heater,
Heating system, fuel dryer system, inlet air of boiler heating system.
In described front desulfurizing tower, the pH value of serosity is 4-5.5, and slurry temperature is 45 DEG C -55 DEG C;In described rear desulfurizing tower
Slurry pH value is 5.8-6.5, and heat exchange rear slurry temperature is at 25 DEG C -35 DEG C.
Above-mentioned desulfurization is lowered the temperature potentiation and the system of heat recovery, the reduction of desulfurization slurry temperature, is by by evaporating
The heat pump heat exchanging of the compositions such as device, compressor, condenser is realized, and carries out heat exchange using compression heat pump or absorption heat pump.
Beneficial effects of the present invention:
1st, the present invention carries out reheating, effectively solving flue gas with water using the heat obtaining from serosity to the flue gas after purifying
The chimney etching problem causing, remaining heat is used for heat supply, inlet air of boiler heats and as-fired fuel is dried etc., many by heat
Level utilizes, and realizes the maximization of energy saving of system.
2nd, the present invention reduces the temperature of desulfurization slurry by heat exchange, make the temperature of serosity from 45 DEG C -55 DEG C be reduced to 25 DEG C -
35 DEG C, thus effectively improving SO2With absorbent CaCO3Dissolubility in the liquid phase, improves mass transfer rate, and then effectively improves de-
Sulphur efficiency(Desulfuration efficiency more than 99%), realize flue gas SO2Ultra-clean discharge, carries out Multi-class propagation after waste heat recovery simultaneously, has
Effect improves the heat utilization efficiency of whole therrmodynamic system, effectively reduces operating cost on the whole, realizes the energy-efficient of therrmodynamic system
Reduce discharging.
3rd, the present invention is based on conventional wet lay flue gas desulfurization technique, improves desulfuration efficiency further by reducing slurry temperature,
And energy-efficient by realizing to the Multi-class propagation of waste heat, realizing coal-fired flue-gas SO2Effectively reduce whole while ultra-clean discharge
The operating cost of individual system, has broad application prospects.
Brief description
Fig. 1 is the cooling potentiation of single column single cycle wet process of FGD and bootstrap system schematic diagram;
Fig. 2 is the cooling potentiation of single column Two-way Cycle wet process of FGD and bootstrap system schematic diagram;
Fig. 3 is the cooling potentiation of double tower Two-way Cycle wet process of FGD and bootstrap system schematic diagram;
Wherein, 1, desulfurizing tower, 1-1, front desulfurizing tower, 1-2, rear desulfurizing tower, 2, wet-type electrostatic defroster, 3, flue gas reheat
Device, 4, chimney, 5, circulation slurry pump, 6, heat exchanger, 7, cool slurry circulating pump(Optional), 8, vaporizer, 9, compressor, 10,
Condenser, 11, heating system, 12, fuel dryer system, 13, inlet air of boiler heating system, 14, upper spraying layer, 15, liquid receptacle,
16th, lower spraying layer, 17, serum pot.
Specific embodiment
The invention will be further described with embodiment below in conjunction with the accompanying drawings.
Embodiment 1
Potentiation and the system of heat recovery as shown in figure 1, a kind of desulfurization is lowered the temperature, described system is that single column single cycle is wet
Method flue gas desulfurization cooling potentiation and waste heat recycling system, including desulfurizing tower 1, wet-type electrostatic defroster 2, smoke re-heater 3,
Chimney 4, circulation slurry pump 5, heat exchanger 6, cool slurry circulating pump 7, vaporizer 8, compressor 9, condenser 10, heating system
11st, fuel dryer system 12, inlet air of boiler heating system 13, described desulfurizing tower 1 arranges circulation slurry pump 5, in described desulfurizing tower 1
The pH value of serosity is 5-5.5, and the outlet of described desulfurizing tower 1 passes sequentially through wet-type electrostatic defroster 2, smoke re-heater 3 and chimney 4
Connect, described smoke re-heater 3 is connected with condenser 10, described condenser 10 also respectively with described heating system 11, fuel stem
Drying system 12, inlet air of boiler heating system 13 connect, and described condenser 10 is connected with vaporizer 8 by compressor 9, described evaporation
Device 8 is sequentially passed through heat exchanger 6, cool slurry circulating pump 7 or is directly connected with desulfurizing tower 1 by desulfurizing tower circulation slurry pump 5.
Desulfurization cooling potentiation based on said system and the method for heat recovery, the flue gas that boiler is discharged is in desulfurizing tower
In 1, SO is carried out by the effect of recycle liquid pump 52Purified treatment, the flue gas discharged from desulfurizing tower 1 sequentially passes through wet electrostatic and removes
The demisting of day with fog 2, and the heat effect of smoke re-heater 3, are discharged by chimney 4, and in desulfurizing tower 1, the higher serosity of temperature passes through
Cool slurry circulating pump 7 or directly act on heat exchanger 6 heat exchange using desulfurizing tower circulation slurry pump, the heat after heat exchange is successively
Through vaporizer 8, compressor 9, condenser 10 by heat pass to smoke re-heater 3, heating system 11, fuel dryer system 12,
Inlet air of boiler heating system 13, heat exchange rear slurry temperature is 25 DEG C -35 DEG C.
Embodiment 2
Potentiation and the system of heat recovery as shown in Fig. 2 a kind of desulfurization is lowered the temperature, described system is that single column Two-way Cycle is wet
Method flue gas desulfurization cooling potentiation and waste heat recycling system, including desulfurizing tower 1, wet-type electrostatic defroster 2, smoke re-heater 3,
Chimney 4, circulation slurry pump 5, heat exchanger 6, cool slurry circulating pump 7, vaporizer 8, compressor 9, condenser 10, heating system
11st, fuel dryer system 12, inlet air of boiler heating system 13, upper spraying layer 14, liquid receptacle 15, lower spraying layer 16, serum pot 17,
In described desulfurizing tower 1, the pH value of serosity is 4-5.5, and stable rear slurry temperature is 35 DEG C -45 DEG C, and described desulfurizing tower 1 is arranged
Circulation slurry pump 5, is sequentially arranged lower spraying layer 16, liquid receptacle 15, upper spraying layer 14 from bottom to top in described desulfurizing tower 1, described
Liquid receptacle 15 is connected with serum pot 17, the outlet of described desulfurizing tower 1 pass sequentially through wet-type electrostatic defroster 2, smoke re-heater 3 with
Chimney 4 connects, and described smoke re-heater 3 is connected with condenser 10, described condenser 10 also respectively with described heating system 11, combustion
Material drying system 12, inlet air of boiler heating system connect 13, and described condenser 10 is connected with vaporizer 8 by compressor 9, described
Vaporizer 8 is sequentially passed through heat exchanger 6, cool slurry circulating pump 7 or is directly connected by desulfurizing tower circulation slurry pump and serum pot 17
Connect.
Desulfurization cooling potentiation based on said system and the method for heat recovery, the flue gas that boiler is discharged is in desulfurizing tower
The interior effect by circulation slurry pump 5 and lower spraying layer 16 carries out SO2Preliminary purification process, flue gas after preliminary purification passes through
Upper spraying layer 13 carries out deep purifying process, and the serosity that upper spraying layer 13 sprays passes through liquid receptacle 15 and collects entrance serum pot 17,
The flue gas discharged from desulfurizing tower sequentially passes through the demisting of wet-type electrostatic defroster 2, and the heat effect of smoke re-heater 3, by cigarette
Chimney 4 discharges, and in serum pot 17, the higher serosity of temperature passes through cool slurry circulating pump 7 or directly utilizes desulfurizing tower circulation slurry pump
5 act on heat exchanger 6 heat exchange, the heat after heat exchange sequentially passes through vaporizer 8, heat is passed to cigarette by compressor 9, condenser 10
Gas reheater 3, heating system 11, fuel dryer system 12, inlet air of boiler heating system 13, the slurry pH value in described serum pot
For 5.8-6.5, heat exchange rear slurry temperature is between 25 DEG C -35 DEG C.Slurry pH value in described desulfurization tower bottom stock tank is in 4-5.5
Between, with the balance of heat, the slurry temperature in the stock tank of bottom gradually decreases down between 35 DEG C -45 DEG C.
Embodiment 3
Potentiation and the system of heat recovery as shown in figure 3, a kind of desulfurization is lowered the temperature, described device is that double tower Two-way Cycle is wet
Method flue gas desulfurization cooling potentiation and waste heat recycling system, including front desulfurizing tower 1-1, rear desulfurizing tower 1-2, wet electrostatic demisting
Device 2, smoke re-heater 3, chimney 4, circulation slurry pump 5, heat exchanger 6, cool slurry circulating pump 7, vaporizer 8, compressor 9, cold
Condenser 10, heating system 11, fuel dryer system 12, inlet air of boiler heating system 13, described front desulfurizing tower 1-1 passes through outlet flue
It is connected with rear desulfurizing tower 1-2, described front desulfurizing tower 1-1, rear desulfurizing tower 1-2 are respectively provided with circulation slurry pump 5, described rear desulfurizing tower 1-
2 gas outlet passes sequentially through wet-type electrostatic defroster 2, smoke re-heater 3 is connected with chimney 4, described smoke re-heater 3 and condensation
Device 10 connects, described condenser 10 also respectively with described heating system 11, fuel dryer system 12, inlet air of boiler heating system 13
Connect, described condenser 10 is connected with vaporizer 8 by compressor 9, and described vaporizer 8 sequentially passes through heat exchanger 6, cool slurry
Circulating pump 7 or be directly connected with rear desulfurizing tower 1-2 by desulfurizing tower circulation slurry pump 5.
Desulfurization cooling potentiation based on said system and the method for heat recovery, the flue gas that boiler is discharged is in front desulfurization
Carry out SO in tower 1-12Preliminary purification process, after entering afterwards, desulfurizing tower 1-2 carries out the deep purifying of flue gas, from rear desulfurizing tower
1-2 expellant gas sequentially pass through wet-type electrostatic defroster 2 demisting, and after smoke re-heater 3 heating, are discharged by chimney 4, after
The effect that in desulfurizing tower 1-2, the higher serosity of temperature passes through cool slurry circulating pump 7 or directly utilizes desulfurizing tower circulation slurry pump 5
In heat exchanger 6 heat exchange, the heat after heat exchange sequentially passes through vaporizer 8, heat is passed to flue gas reheat by compressor 9, condenser 10
Device 3, heating system 11, fuel dryer system 12, inlet air of boiler heating system 13, after heat exchange after in desulfurizing tower slurry temperature 25
DEG C~35 DEG C, pH value is 5.8-6.5.
Although the above-mentioned accompanying drawing that combines is described to the specific embodiment of the present invention, not model is protected to the present invention
The restriction enclosed, one of ordinary skill in the art should be understood that on the basis of technical scheme, and those skilled in the art are not
Need to pay the various modifications that creative work can make or deformation still within protection scope of the present invention.