CN109569293A - A kind of equipment for denitrifying flue gas and denitration method for flue gas - Google Patents
A kind of equipment for denitrifying flue gas and denitration method for flue gas Download PDFInfo
- Publication number
- CN109569293A CN109569293A CN201811506326.6A CN201811506326A CN109569293A CN 109569293 A CN109569293 A CN 109569293A CN 201811506326 A CN201811506326 A CN 201811506326A CN 109569293 A CN109569293 A CN 109569293A
- Authority
- CN
- China
- Prior art keywords
- liquid
- solution
- flue gas
- equipment
- urea
- 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.)
- Pending
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
- B01D53/86—Catalytic processes
- B01D53/90—Injecting reactants
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
- B01D53/86—Catalytic processes
- B01D53/8621—Removing nitrogen compounds
- B01D53/8625—Nitrogen oxides
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2251/00—Reactants
- B01D2251/20—Reductants
- B01D2251/206—Ammonium compounds
- B01D2251/2062—Ammonia
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2258/00—Sources of waste gases
- B01D2258/02—Other waste gases
- B01D2258/0283—Flue gases
Landscapes
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Biomedical Technology (AREA)
- Analytical Chemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Treating Waste Gases (AREA)
Abstract
The present invention provides a kind of equipment for denitrifying flue gas and denitration method for flue gas.The equipment for denitrifying flue gas includes: liquid-supply unit, and liquid-supply unit includes urea liquid liquid supply equipment and liquid supply equipment containing nitrate solutions；Solution hydrolysis unit, liquid-supply unit are connected by pipeline with solution hydrolysis unit to provide urea liquid to solution hydrolysis unit and contain nitrate solutions, and solution hydrolysis unit is hydrolyzed by urea liquid and containing nitrate solutions to form the HNO of gasification3And NH3；SCR denitration unit is connected with solution hydrolysis unit.When flue-gas temperature is lower than threshold temperature, supplies urea liquid simultaneously using liquid-supply unit and contain nitrate solutions, the HNO hydrolyzed to form3And NH3As the also Primordial Qi of SCR denitration, realizes and abundant denitration is carried out to flue gas at low temperature and not will lead to HNO3And NH3Waste.When flue-gas temperature is higher than threshold temperature, urea liquid is provided using liquid-supply unit, realizes SCR denitration unit to the NO_x Reduction by Effective of high-temperature flue gas.
Description
Technical field
The present invention relates to filed of flue gas purification, in particular to a kind of equipment for denitrifying flue gas and denitration method for flue gas.
Background technique
SCR denitration technology is a kind of effective flue gases purification.SCR denitration device design optimal reaction temperature be
320 DEG C~420 DEG C, the activity of catalyst is higher at this time, and denitration efficiency is up to 90%.SCR denitration technology is for restoring flue gas
Reaction temperature requirement it is very stringent, when boiler load is too low, will appear flue-gas temperature in denitration unit at SCR and urge
The unmatched situation of agent optimum working temperature is unfavorable for the progress of denitration reaction, so that NOxConcentration of emission get higher.
Since power surplus and peak regulation need, the unit of part power plant is in underrun state for a long time, generally works as denitration unit
In temperature be lower than 310 DEG C or so when, denitration efficiency can be significantly lower than design value, and cause the escaping of ammonia increase, catalyst lose
The problems such as living and air preheater blocking aggravation, traditional SCR device is caused to be unable to operate normally.
SCR denitration method in the prior art includes that steam will be used to hydrolyze ammonia, to generate ammonia gas vapor；Steam ammonia
Vapour and smoke contacts are to restore flue gas.But optimal reaction temperature of this method due to that cannot reach denitrification apparatus, cannot
It restores flue gas to the greatest extent, and also creates the waste of raw material and the energy.
Summary of the invention
The main purpose of the present invention is to provide a kind of equipment for denitrifying flue gas and denitration method for flue gas, to solve the prior art
Middle flue-gas temperature is too low to cannot proceed normally the problem of flue gas restores.
To achieve the goals above, according to an aspect of the invention, there is provided a kind of equipment for denitrifying flue gas, the flue gas are de-
Nitre device includes: liquid-supply unit, and liquid-supply unit includes urea liquid liquid supply equipment and liquid supply equipment containing nitrate solutions；Solution water
Unit is solved, liquid-supply unit is connected by pipeline to provide urea liquid to solution hydrolysis unit and containing nitric acid with solution hydrolysis unit
Root solution, solution hydrolysis unit are hydrolyzed by urea liquid and containing nitrate solutions to form the HNO of gasification3And NH3；SCR denitration list
Member is connected with solution hydrolysis unit.
Further, above-mentioned solution hydrolysis unit includes the heating equipment and solution hydrolysis device of connection setting, wherein plus
The upstream or downstream of solution hydrolysis device is arranged in hot equipment.
Further, above-mentioned heating equipment is arranged in the upstream of solution hydrolysis device, heating equipment have thermal medium entrance,
Hot liquid inlet to be added and the outlet of the first raffinate, solution hydrolysis device has hydrolysate outlet and the outlet of the second raffinate, to be added
Hot liquid inlet is connected with liquid-supply unit, and hydrolysate outlet is connected with SCR denitration unit, and the outlet of the second raffinate enters with thermal medium
Mouth is connected.
Further, above-mentioned liquid-supply unit further includes solution pre-processing device, and solution pre-processing device includes dissolvers, urine
Plain solution liquid supply equipment and liquid supply equipment containing nitrate solutions are connected by pipeline respectively with dissolvers, and are set respectively on each pipeline
It is equipped with switch valve.
Further, above-mentioned first raffinate outlet is connected with dissolvers, is preferably provided with blender in dissolvers.
Further, above-mentioned solution pre-processing device further include: the first solution memory, the first solution memory and dissolution
Device is connected by the first transfer pipeline, and the first Liquid valve is provided on the first transfer pipeline；Second solution memory, second is molten
Liquid memory is connected with dissolvers by the second transfer pipeline, and second liquid valve is provided on the second transfer pipeline, and preferably
Force (forcing) pump is provided on one transfer pipeline and the second transfer pipeline.
Further, above-mentioned first solution memory is connected with heating equipment by third transfer pipeline, third delivery pipe
Road is provided with third Liquid valve；Second solution memory is connected with heating equipment by the 4th transfer pipeline, the 4th conveying
The 4th Liquid valve is provided on pipeline.
According to another aspect of the present invention, a kind of denitration method for flue gas is provided, comprising: step S1 detects SCR denitration
Flue-gas temperature；And step S2, when flue-gas temperature is lower than threshold temperature, using urea liquid and containing the mixing of nitrate solutions
The HNO that solution hydrolyzes to form3And NH3Also Primordial Qi as SCR denitration；It is molten using urea when flue-gas temperature is higher than threshold temperature
The NH that liquid hydrolyzes to form3As also Primordial Qi.
Further, the above-mentioned nitrate solutions that contain are nitric acid solution, when flue-gas temperature is lower than threshold temperature, urea and nitre
The molar ratio of acid is 1.3:1 to 1.8:1；It is nitric acid ammonia solution containing nitrate solutions, wherein the molar ratio of urea and nitric acid ammonia is
0.8:1 to 1.2:1, preferably 1:1.
Further, when above-mentioned flue-gas temperature is lower than threshold temperature, step S2 includes: by urea liquid and containing nitrate anion
It is heated after solution mixing, forms hot miscible fluid；Hot miscible fluid is set to hydrolyze to form HNO3And NH3；Utilize HNO3And NH3As reduction
Gas carries out denitration to flue gas.
Further, when above-mentioned flue-gas temperature is greater than threshold temperature, step S2 includes: to heat urea liquid, is formed
Hot solution；Hot solution is set to hydrolyze to form NH3；Utilize NH3Denitration is carried out to flue gas as also Primordial Qi.
Further, the hydrolytic process of above-mentioned steps S2 generates raffinate, and wherein step S2 further comprises: being added using raffinate
Hot mixing solution or urea liquid.
Further, it is excellent in the range of mixed solution or urea liquid are heated to 150 DEG C to 200 DEG C by above-mentioned steps S2
Selecting threshold temperature is 310 DEG C.
Further, before heating to mixed solution described above or the urea liquid, the step S2 is also
Including the process compressed to the mixed solution or the urea liquid, preferably by force (forcing) pump to the mixed solution or
It is 2.4~2.8MPa that the urea liquid, which carries out compression and the gauge pressure of the force (forcing) pump,.
It applies the technical scheme of the present invention, the liquid-supply unit of the application is configured with urea liquid liquid supply equipment and simultaneously containing nitre
Acid group solution liquid supply equipment, therefore, when flue-gas temperature be lower than threshold temperature when, using liquid-supply unit simultaneously supply urea liquid and
Containing nitrate solutions, HNO that the mixed solution of the two hydrolyzes to form3And NH3As the also Primordial Qi of SCR denitration, make SCR denitration list
First efficient operation can be realized and carry out abundant denitration to flue gas at low temperature and not will lead to HNO3And NH3Waste.And work as cigarette
When temperature degree is higher than threshold temperature, urea liquid is provided using the urea liquid liquid supply equipment of liquid-supply unit, then uses urea
The NH that solution hydrolyzes to form3As also Primordial Qi, realize SCR denitration unit to the NO_x Reduction by Effective of high-temperature flue gas.
Detailed description of the invention
The accompanying drawings constituting a part of this application is used to provide further understanding of the present invention, and of the invention shows
Examples and descriptions thereof are used to explain the present invention for meaning property, does not constitute improper limitations of the present invention.In the accompanying drawings:
Fig. 1 shows the structural schematic diagram for the equipment for denitrifying flue gas that a kind of exemplary embodiment according to the present invention provides；
And
Fig. 2 shows the structural schematic diagrams of the equipment for denitrifying flue gas provided according to an embodiment of the present invention.
Wherein, the above drawings include the following reference numerals:
1, liquid-supply unit；11, urea liquid liquid supply equipment；12, liquid supply equipment containing nitrate solutions；131, dissolvers；
132, the first solution memory；133, the second solution memory；134, force (forcing) pump；
2, solution hydrolysis unit；21, heating equipment；22, solution hydrolysis device；
3, SCR denitration unit.
Specific embodiment
It should be noted that in the absence of conflict, the features in the embodiments and the embodiments of the present application can phase
Mutually combination.The present invention will be described in detail below with reference to the accompanying drawings and embodiments.
As the application background technique is analyzed, the method for denitration of the prior art cannot be to flue gas when flue-gas temperature is too low
Normal reduction is carried out, causes fume treatment insufficient and wastage of material, in order to solve this problem, it is de- that this application provides a kind of flue gases
Nitre device and denitration method for flue gas.
In a kind of typical embodiment of the application, a kind of equipment for denitrifying flue gas is provided, as illustrated in fig. 1 and 2, the cigarette
Gas denitrification apparatus includes liquid-supply unit 1, solution hydrolysis unit 2 and SCR denitration unit 3, and liquid-supply unit includes urea liquid feed flow
Equipment 11 and liquid supply equipment containing nitrate solutions 12；Liquid-supply unit 1 and solution hydrolysis unit 2 are connected by pipeline with to solution water
Solve unit 2 provide urea liquid and contain nitrate solutions, solution hydrolysis unit 2 by urea liquid and containing nitrate solutions hydrolyze with
Form the HNO of gasification3And NH3；SCR denitration unit 3 is connected with solution hydrolysis unit 2.
The liquid-supply unit 1 of the application is configured with urea liquid liquid supply equipment 11 and liquid supply equipment containing nitrate solutions simultaneously
12, therefore, when flue-gas temperature is lower than threshold temperature, supplies urea liquid simultaneously using liquid-supply unit 1 and contain nitrate solutions,
The HNO that the mixed solution of the two hydrolyzes to form3And NH3As the also Primordial Qi of SCR denitration, make 3 efficient operation of SCR denitration unit, energy
Enough realize carries out abundant denitration to flue gas at low temperature and not will lead to HNO3And NH3Waste.And when flue-gas temperature is higher than threshold value
When temperature, urea liquid is provided using the urea liquid liquid supply equipment 11 of liquid-supply unit, is then hydrolyzed to form using urea liquid
NH3As also Primordial Qi, realize SCR denitration unit 3 to the NO_x Reduction by Effective of high-temperature flue gas.
In order to improve solution hydrolysis unit 2 to the effectively hydrolyzing of handled liquid, and to enter SCR denitration unit 3
Hydrolysis gas have enough temperature, preferably as shown in Fig. 2, above-mentioned solution hydrolysis unit 2 include connection setting heating equipment
21 and solution hydrolysis device 22, wherein the upstream or downstream of solution hydrolysis device 22 is arranged in heating equipment 21.
In a kind of preferred embodiment, as shown in Fig. 2, the upper of solution hydrolysis device 22 is arranged in above-mentioned heating equipment 21
Trip, the solution first provided liquid-supply unit 1 heat, and reach solution temperature conducive to hydrolysis temperature, and then improve hydrolysis
Efficiency.Additionally, it is preferred that above-mentioned heating equipment 21 has thermal medium entrance, hot liquid inlet to be added and the outlet of the first raffinate, solution
Hydrolysis device 22 has hydrolysate outlet and the outlet of the second raffinate, and hot liquid inlet to be added is connected with liquid-supply unit 1, and hydrolysis produces
Object outlet is connected with SCR denitration unit 3, and the outlet of the second raffinate is connected to utilize 22 raffinate of solution hydrolysis device with thermal medium entrance
The temperature of the heat raffinate hot liquid to be added in heating equipment 21 is heated at 200 DEG C or so, realize the energy
Comprehensive utilization.
In the application another kind embodiment, as shown in Fig. 2, it is preferred that above-mentioned liquid-supply unit 1 further includes that solution pre-treatment is set
It is standby, solution pre-processing device include dissolvers 131, urea liquid liquid supply equipment 11 and liquid supply equipment containing nitrate solutions 12 with it is molten
It solves device 131 to be connected by pipeline respectively, and is respectively arranged with switch valve on each pipeline.In urea liquid liquid supply equipment 11 and contain nitre
Dissolvers 131 is set before acid group solution liquid supply equipment 12, is uniformly mixed two kinds of solution when needing using two kinds of solution, or
The urea and nitrate anion that person provides urea liquid liquid supply equipment 11 and liquid supply equipment containing nitrate solutions 12 are in dissolvers 131
Dissolution mixing, and then be conducive to hydrolysis and carry out.Preferably, it is provided with blender in above-mentioned dissolvers 131, to optimize liquid mixing
Effect.
Furthermore it is preferred that as shown in Fig. 2, above-mentioned first raffinate outlet be connected with dissolvers 131, utilize the residual of heating equipment 21
Lytic agent of the liquid as dissolvers 131, realizes the recycling of raffinate, and extra raffinate can send to sewage plant and be handled
Recycling or outlet afterwards.Such as the Residue temperature of heating equipment 21 is down to 90 DEG C or so, enter back into dissolvers 131 as urea and
The lytic agent of ammonium nitrate, extra raffinate are sent to sewage plant processing.
In addition, in order to improve the stability of the operation of solution hydrolysis unit 2, preferably as shown in Fig. 2, above-mentioned solution pre-treatment is set
Standby further includes the first solution memory 132 and the second solution memory 133, and the first solution memory 132 passes through with dissolvers 131
First transfer pipeline is connected, and the first Liquid valve is provided on the first transfer pipeline；Second solution memory 133 and dissolvers
131 are connected by the second transfer pipeline, and second liquid valve is provided on the second transfer pipeline.It is set in solution pre-processing device
Two solution memories are set, separately to carry out storage buffering to solution required under different flue-gas temperatures.In addition to accelerating water
Solution carries out, and is provided with force (forcing) pump 134 on preferably the first transfer pipeline and the second transfer pipeline.In order to simplify circuit design, first
Transfer pipeline and the second transfer pipeline merge in upstream, and force (forcing) pump 134 is arranged on the pipeline of merging, the first Liquid valve and the
Two Liquid valves are arranged on downstream branch pipeline.The edge of liquid-supply unit 1 and solution hydrolysis unit 2 is overcome using force (forcing) pump 134
Journey resistance, and guarantee the reducing agent that hydrolyzes to form jet velocity is sufficiently large in SCR system to mix to meet with the uniform of flue gas.
In addition, in order to flexibly control the supply of liquid, preferably as shown in Fig. 2, above-mentioned first solution memory 132 and heating
Equipment 21 is connected by third transfer pipeline, and third Liquid valve is provided on third transfer pipeline；Second solution memory 133
It is connected with heating equipment 21 by the 4th transfer pipeline, is provided with the 4th Liquid valve on the 4th transfer pipeline.
In another typical embodiment of the application, a kind of denitration method for flue gas is provided, the denitration method for flue gas
Include: step S1, detects the flue-gas temperature of SCR denitration；And step S2 utilizes urine when flue-gas temperature is lower than threshold temperature
The HNO that plain solution and mixed solution containing nitrate solutions hydrolyze to form3And NH3Also Primordial Qi as SCR denitration；When flue gas temperature
Degree is higher than the NH hydrolyzed to form when threshold temperature using urea liquid3As also Primordial Qi.
The denitration method for flue gas of the application using urea liquid and contains nitrate anion when flue-gas temperature is lower than threshold temperature
The HNO that the mixed solution of solution hydrolyzes to form3And NH3As the also Primordial Qi of SCR denitration, make SCR denitration unit efficient operation, energy
Enough realize carries out abundant denitration to flue gas at low temperature and not will lead to HNO3And NH3Waste.And when flue-gas temperature is higher than threshold value
When temperature, the NH that is hydrolyzed to form using urea liquid3As also Primordial Qi, realize SCR denitration unit to the efficient de- of high-temperature flue gas
Nitre.
According to verification experimental verification, preferably above-mentioned threshold temperature is 310 DEG C.So as to improve the treatment effeciency of flue gas under low temperature
With the utilization rate of also Primordial Qi.
When flue-gas temperature is lower than threshold temperature, the NO reduction reaction of generation in SCR denitration device are as follows: HNO3+2NO+3NH3
→3N2+5H2O, denitration efficiency of the reaction at 200 DEG C~300 DEG C is up to 90%；When flue-gas temperature is higher than threshold temperature, SCR
The NO reduction reaction occurred in denitrification apparatus are as follows: 4NO+4NH3+O2→4N2+6H2O。
In order to improve the utilization efficiency of urea and nitric acid and improve the SCR denitration efficiency of low-temperature flue gas, preferably contain nitric acid
Root solution is nitric acid solution, and when flue-gas temperature is lower than threshold temperature, the molar ratio of urea and nitric acid is 1.3:1 to 1.8:1, excellent
It is selected as 1.5:1.In addition, when being nitric acid ammonia solution containing nitrate solutions, wherein the molar ratio of urea and nitric acid ammonia be 0.8:1 extremely
1.2:1 preferably 1:1.
In a kind of embodiment of the application, when flue-gas temperature is lower than threshold temperature, above-mentioned steps S2 includes: that urea is molten
Liquid and containing nitrate solutions mixing after heat, form hot miscible fluid；Hot miscible fluid is set to hydrolyze to form HNO3And NH3；Utilize HNO3With
NH3Denitration is carried out to flue gas as also Primordial Qi.It is mixed to urea liquid and first containing nitrate solutions and heats and then be hydrolyzed afterwards,
So that the HNO that hydrolysis efficiency is improved and hydrolyzed to form3And NH3Uniformity.
In addition, preferably above-mentioned steps S2 includes: to heat urea liquid when flue-gas temperature is greater than threshold temperature, formed
Hot solution；Hot solution is set to hydrolyze to form NH3；Utilize NH3Denitration is carried out to flue gas as also Primordial Qi.It is molten to urea before hydrolysis
Liquid is heated, and hydrolysis efficiency is improved.
The hydrolytic process of above-mentioned steps S2 generates raffinate, and in order to improve the utilization efficiency of heat, preferred steps S2 is further
It include: using raffinate heating mixed solution or urea liquid.
According to hydrolysis required temperature, mixed solution or urea liquid are heated to 150 DEG C to 200 DEG C by preferably above-mentioned steps S2
In the range of.
In order to overcome the on-way resistance of liquid-supply unit and solution hydrolysis unit, and guarantee that reducing agent sprays in SCR system
Speed is sufficiently large to be mixed to meet with the uniform of flue gas, and before heating to mixed solution or urea liquid, step S2 is also
Including the process compressed to mixed solution or urea liquid, mixed solution or urea liquid are carried out preferably by force (forcing) pump
The gauge pressure of compression and force (forcing) pump is 2.4~2.8MPa.
Below with reference to embodiment and comparative example, the beneficial effect of the application is further illustrated.
Embodiment 1
The structure with reference to shown in Fig. 2, in boiler running process, when the display flue-gas temperature of temperature measuring set is greater than 310 DEG C
When, nitric acid/ammonium nitrate regulating valve, second liquid valve and the 4th Liquid valve are kept closed, urea regulating valve, first
Liquid valve and third Liquid valve are kept open, and urea is transported to dissolvers 131 by urea liquid liquid supply equipment 11
In, agitated device stirring is made into urea liquid, urea liquid is transported in the first solution memory 132 using force (forcing) pump 134,
Force (forcing) pump 134 is forced into gauge pressure 2.6MPa or so, and urea liquid is transported in heating equipment 21 followed by solution transfer pump,
And exchange heat with the raffinate come out from solution hydrolysis device 22, the urea liquid that heating equipment 21 exports is heated to about 180 DEG C,
Subsequent urea liquid is transported to solution hydrolysis device 22, urea liquid and directly occurs from the steam that turbine low pressure cylinder extracts
The hydrolysis of urea generates NH3, the NH of generation3It is injected into SCR denitration unit 3, then flue gas is restored by SCR denitration reaction
In NO:4NO+4NH3+O2→4N2+6H2O；Denitration efficiency of the reaction at 320 DEG C~420 DEG C is up to 90%.
Embodiment 2
The structure with reference to shown in Fig. 2, when the displays temperature of temperature measuring set is lower than 310 DEG C, is closed in boiler running process
The first Liquid valve and third Liquid valve are closed, and opens nitric acid/ammonium nitrate regulating valve, second liquid valve and the 4th liquid
Body valve, urea and nitric acid or urea and ammonium nitrate are sufficiently mixed the dissolvers 131 when using ammonium nitrate in dissolvers 131
The molar ratio of urea and ammonium nitrate is 1:1 in mixed solution, using urea and nitric acid in the mixed solution of dissolvers 131 when nitric acid
Molar ratio be 1.5:1, urea liquid is transported in the second solution memory 133 using force (forcing) pump 134, force (forcing) pump 134 plus
It is followed by solution transfer pump that the mixed solution for mixing molten or urea and ammonium nitrate of urea and nitric acid is defeated to gauge pressure 2.6MPa
It is sent in heating equipment 21, and exchanges heat with the raffinate come out from hydrolysis device, the mixed solution that heating equipment 21 exports is added
Heat arrives about 180 DEG C, and nitric acid or decomposing ammonium nitrate are HNO at this time3Or HNO3And NH3, subsequent mixed solution is transported to hydrolysis and sets
Standby, mixed solution and the hydrolysis that urea directly occurs from the steam that turbine low pressure cylinder extracts generate NH3, the NH of generation3
In the NH with nitric acid before or decomposing ammonium nitrate generation3And HNO3It sprays into together and denitration reaction, SCR occurs in SCR denitration unit 3
The NO reduction reaction occurred in denitration unit 3 are as follows: HNO3+2NO+3NH3→3N2+5H2O, the reaction is at 200 DEG C~300 DEG C
Denitration efficiency is up to 90%.
Embodiment 3
Difference from Example 2 is that mixed solution is the mixed solution of ammonium nitrate and urea, wherein urea and nitric acid
The molar ratio of ammonium is 0.8:1, and denitration efficiency is up to 86%.
Embodiment 4
Difference from Example 2 is that mixed solution is the mixed solution of ammonium nitrate and urea, wherein urea and nitric acid
The molar ratio of ammonium is 1.2:1, and denitration efficiency is up to 89%.
Embodiment 5
Difference from Example 2 is that mixed solution is the mixed solution of ammonium nitrate and urea, wherein urea and nitric acid
The molar ratio of ammonium is 0.6:1, and denitration efficiency is up to 80%.
Embodiment 6
Difference from Example 2 is that mixed solution is the mixed solution of nitric acid and urea, wherein urea and nitric acid
Molar ratio is 1.3:1, and denitration efficiency is up to 85%.
Embodiment 7
Difference from Example 2 is that mixed solution is the mixed solution of nitric acid and urea, wherein urea and nitric acid
Molar ratio is 1.8:1, and denitration efficiency is up to 89%.
Embodiment 8
Difference from Example 2 is that mixed solution is the mixed solution of nitric acid and urea, wherein urea and nitric acid
Molar ratio is 1.0:1, and denitration efficiency is up to 81%.
Comparative example 1
Difference from Example 1 is that the displays temperature of temperature measuring set is lower than 310 DEG C, and denitration efficiency is on 50% left side
The right side, and NH3Utilization rate it is lower, detect NH3Escape.
It can be seen from the above description that the above embodiments of the present invention realized the following chievements:.
The liquid-supply unit of the application is configured with urea liquid liquid supply equipment and liquid supply equipment containing nitrate solutions simultaneously, because
This is supplied urea liquid simultaneously using liquid-supply unit and contains nitrate solutions when flue-gas temperature is lower than threshold temperature, the two
The HNO that mixed solution hydrolyzes to form3And NH3As the also Primordial Qi of SCR denitration, makes SCR denitration unit efficient operation, can be realized
Abundant denitration is carried out to flue gas at low temperature and not will lead to HNO3And NH3Waste.And when flue-gas temperature is higher than threshold temperature
When, urea liquid, the NH then hydrolyzed to form using urea liquid are provided using the urea liquid liquid supply equipment of liquid-supply unit3Make
For also Primordial Qi, realize SCR denitration unit to the NO_x Reduction by Effective of high-temperature flue gas.
The foregoing is only a preferred embodiment of the present invention, is not intended to restrict the invention, for the skill of this field
For art personnel, the invention may be variously modified and varied.All within the spirits and principles of the present invention, made any to repair
Change, equivalent replacement, improvement etc., should all be included in the protection scope of the present invention.
Claims (13)
1. a kind of equipment for denitrifying flue gas, which is characterized in that the equipment for denitrifying flue gas includes:
Liquid-supply unit (1), the liquid-supply unit (1) include urea liquid liquid supply equipment (11) and liquid supply equipment containing nitrate solutions
(12)；
Solution hydrolysis unit (2), the liquid-supply unit (1) and the solution hydrolysis unit (2) are connected by pipeline with to described
Solution hydrolysis unit (2) provides urea liquid and contains nitrate solutions, the solution hydrolysis unit (2) by the urea liquid and
It is described to be hydrolyzed containing nitrate solutions to form the HNO of gasification3And NH3；
SCR denitration unit (3) is connected with the solution hydrolysis unit (2).
2. equipment for denitrifying flue gas according to claim 1, which is characterized in that the solution hydrolysis unit (2) includes connection
The heating equipment (21) and solution hydrolysis device (22) of setting, wherein the heating equipment (21) setting is set in solution hydrolysis
The upstream or downstream of standby (22).
3. equipment for denitrifying flue gas according to claim 2, which is characterized in that the heating equipment (21) is arranged described molten
The upstream of liquid hydrolysis device (22), the heating equipment (21) have thermal medium entrance, hot liquid inlet to be added and the first raffinate
Outlet, the solution hydrolysis device (22) have hydrolysate outlet and the second raffinate outlet, the hot liquid inlet to be added with
The liquid-supply unit (1) is connected, and the hydrolysate outlet is connected with the SCR denitration unit (3), the second raffinate outlet
It is connected with the thermal medium entrance.
4. equipment for denitrifying flue gas according to claim 3, which is characterized in that before the liquid-supply unit (1) further includes solution
Processing equipment, the solution pre-processing device include dissolvers (131), the urea liquid liquid supply equipment (11) and it is described contain nitre
Acid group solution liquid supply equipment (12) is connected by pipeline respectively with the dissolvers (131), and is respectively set on each pipeline
There is switch valve.
5. equipment for denitrifying flue gas according to claim 4, which is characterized in that the first raffinate outlet and the dissolvers
(131) it is connected, is provided with blender in the preferably described dissolvers (131).
6. equipment for denitrifying flue gas according to claim 4, which is characterized in that the solution pre-processing device further include:
First solution memory (132), the first solution memory (132) and the dissolvers (131) pass through the first conveying
Pipeline is connected, and is provided with the first Liquid valve on first transfer pipeline；
Second solution memory (133), the second solution memory (133) and the dissolvers (131) pass through the second conveying
Pipeline is connected, and is provided with second liquid valve on second transfer pipeline, preferably described first transfer pipeline and described second
Force (forcing) pump (134) are provided on transfer pipeline.
7. equipment for denitrifying flue gas according to claim 6, which is characterized in that the first solution memory (132) and institute
It states heating equipment (21) to be connected by third transfer pipeline, is provided with third Liquid valve on the third transfer pipeline；
The second solution memory (133) is connected with the heating equipment (21) by the 4th transfer pipeline, and the described 4th is defeated
It send and is provided with the 4th Liquid valve on pipeline.
8. a kind of denitration method for flue gas characterized by comprising
Step S1 detects the flue-gas temperature of SCR denitration；And
Step S2, when the flue-gas temperature is lower than threshold temperature, using urea liquid and containing the mixed solution of nitrate solutions
The HNO hydrolyzed to form3And NH3Also Primordial Qi as SCR denitration；Urine is used when the flue-gas temperature is higher than the threshold temperature
The NH that plain solution hydrolyzes to form3As also Primordial Qi.
9. denitration method for flue gas according to claim 8, which is characterized in that the nitrate solutions that contain are nitric acid solution,
When the flue-gas temperature is lower than threshold temperature, the molar ratio of the urea and the nitric acid is 1.3:1 to 1.8:1；It is described to contain
Nitrate solutions are nitric acid ammonia solution, and wherein the molar ratio of urea and nitric acid ammonia is 0.8:1 to 1.2:1, preferably 1:1.
10. denitration method for flue gas according to claim 8 or claim 9, which is characterized in that when the flue-gas temperature is lower than threshold value temperature
When spending, the step S2 includes:
It will be heated after the urea liquid and the mixing containing nitrate solutions, form hot miscible fluid；
The hot miscible fluid is set to hydrolyze to form HNO3And NH3；
Utilize the HNO3And NH3Denitration is carried out to the flue gas as also Primordial Qi；
When the flue-gas temperature is greater than threshold temperature, the step S2 includes:
The urea liquid is heated, hot solution is formed；
The hot solution is set to hydrolyze to form NH3；
Utilize the NH3Denitration is carried out to the flue gas as also Primordial Qi.
11. denitration method for flue gas according to claim 10, which is characterized in that the hydrolytic process of the step S2 generates residual
Liquid, wherein the step S2 further comprises:
The mixed solution or the urea liquid are heated using the raffinate.
12. according to the method described in claim 10, it is characterized in that, the step S2 is by the mixed solution or the urea
Solution is heated in the range of 150 DEG C to 200 DEG C, and the preferably described threshold temperature is 310 DEG C.
13. according to the method described in claim 10, it is characterized in that, to the mixed solution or urea liquid progress
Before heating, the step S2 further includes the process compressed to the mixed solution or the urea liquid, preferably by
The gauge pressure that force (forcing) pump carries out compression and the force (forcing) pump to the mixed solution or the urea liquid is 2.4~2.8MPa.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811506326.6A CN109569293A (en) | 2018-12-10 | 2018-12-10 | A kind of equipment for denitrifying flue gas and denitration method for flue gas |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811506326.6A CN109569293A (en) | 2018-12-10 | 2018-12-10 | A kind of equipment for denitrifying flue gas and denitration method for flue gas |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN109569293A true CN109569293A (en) | 2019-04-05 |
Family
ID=65928739
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811506326.6A Pending CN109569293A (en) | 2018-12-10 | 2018-12-10 | A kind of equipment for denitrifying flue gas and denitration method for flue gas |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109569293A (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2007145548A1 (en) * | 2006-06-13 | 2007-12-21 | Volvo Lastvagnar Ab | Diesel catalyst system |
| CN101462023A (en) * | 2007-12-18 | 2009-06-24 | 德国曼商用车辆股份公司 | Method for improving the hydrolysis of a reducing agent in a waste gas treatment system |
| WO2014044318A1 (en) * | 2012-09-21 | 2014-03-27 | Haldor Topsøe A/S | Method and system for the removal of noxious compounds from engine exhaust gas |
| CN106705091A (en) * | 2016-12-21 | 2017-05-24 | 西安交通大学 | System and method for slowing down deactivation of SCR catalyst and blocking of air preheater |
-
2018
- 2018-12-10 CN CN201811506326.6A patent/CN109569293A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2007145548A1 (en) * | 2006-06-13 | 2007-12-21 | Volvo Lastvagnar Ab | Diesel catalyst system |
| CN101462023A (en) * | 2007-12-18 | 2009-06-24 | 德国曼商用车辆股份公司 | Method for improving the hydrolysis of a reducing agent in a waste gas treatment system |
| WO2014044318A1 (en) * | 2012-09-21 | 2014-03-27 | Haldor Topsøe A/S | Method and system for the removal of noxious compounds from engine exhaust gas |
| CN106705091A (en) * | 2016-12-21 | 2017-05-24 | 西安交通大学 | System and method for slowing down deactivation of SCR catalyst and blocking of air preheater |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106705091B (en) | A kind of system and method for slowing down SCR catalyst inactivation and air preheater and blocking | |
| WO2021184786A1 (en) | Urea direct-injection pyrolysis denitrification device arranged inside outlet flue duct of gas turbine | |
| CN109279625B (en) | Urea hydrolysis ammonia production system and hydrolysis ammonia production method thereof | |
| CN203971726U (en) | SNCR equipment for denitrifying flue gas | |
| CN207713416U (en) | Fire coal boiler fume SCR denitration device urea depth hydrolysis' ammonia system | |
| CN101928014B (en) | Process for producing ammonia from urea used for denitration of boiler smoke and system thereof | |
| CN107188198A (en) | A kind of thermal power plant's denitration is pyrolyzed with hydrolysis of urea and is combined ammonia system processed | |
| CN104192862A (en) | Urea hydrolysis ammonia preparation method and device using boiler gas | |
| CN112902680A (en) | Sintering flue gas SCR denitration energy-saving emission-reducing method and system | |
| CN111036076A (en) | Urea hydrolysis ammonia supply system with injection steam as heat source | |
| CN106807193A (en) | A kind of flue-gas denitration process system | |
| CN205216547U (en) | Flue gas denitration process systems | |
| CN207209975U (en) | A kind of urea hydrolysis ammonia producing system for denitrating flue gas | |
| CN109569293A (en) | A kind of equipment for denitrifying flue gas and denitration method for flue gas | |
| CN210303176U (en) | Gas power generation non-combined cycle generating set flue gas denitration system | |
| CN109731472B (en) | Energy-saving boiler flue gas purification system and method | |
| CN207237700U (en) | Flue-gas denitration process system | |
| CN205717280U (en) | Denitration of boiler smoke process system | |
| CN213032227U (en) | SCR flue gas denitration system for preparing ammonia by urea pyrolysis | |
| CN216395900U (en) | Energy-saving urea hydrolysis ammonia preparation denitrification facility based on combustion engine SCR denitration | |
| CN206454499U (en) | The denitrating system of boiler smoke | |
| CN214106467U (en) | Ammonia gas flow regulating device and denitration system | |
| CN205700150U (en) | SCR boiler flue gas denitration system | |
| CN104971613B (en) | Denitration method for flue gas and the powder material spray gun suitable for flue-gas denitration process | |
| CN204125181U (en) | A kind of hydrolysis of urea ammonia-preparing device utilizing boiler gas |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| CB03 | Change of inventor or designer information |
Inventor after: Xu Huijun Inventor after: Zhao Yonggang Inventor after: Che Defu Inventor after: Bai Yang Inventor after: Du Yongbo Inventor after: Wei Xiaoyang Inventor after: Deng Lei Inventor before: Zhao Yonggang Inventor before: Che Defu Inventor before: Bai Yang Inventor before: Du Yongbo Inventor before: Xu Huijun Inventor before: Wei Xiaoyang Inventor before: Deng Lei |
|
| CB03 | Change of inventor or designer information | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20190405 |
|
| RJ01 | Rejection of invention patent application after publication |