CN110548387A - integrated treatment device and process for ion denitration, desulfurization and dust removal by semidry method - Google Patents
integrated treatment device and process for ion denitration, desulfurization and dust removal by semidry method Download PDFInfo
- Publication number
- CN110548387A CN110548387A CN201910898291.3A CN201910898291A CN110548387A CN 110548387 A CN110548387 A CN 110548387A CN 201910898291 A CN201910898291 A CN 201910898291A CN 110548387 A CN110548387 A CN 110548387A
- Authority
- CN
- China
- Prior art keywords
- desulfurization
- flue
- flue gas
- denitration
- ion
- 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
- 238000006477 desulfuration reaction Methods 0.000 title claims abstract description 127
- 230000023556 desulfurization Effects 0.000 title claims abstract description 127
- 239000000428 dust Substances 0.000 title claims abstract description 126
- 238000000034 method Methods 0.000 title claims abstract description 63
- 230000008569 process Effects 0.000 title claims abstract description 33
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims abstract description 133
- 239000003546 flue gas Substances 0.000 claims abstract description 133
- 150000002500 ions Chemical class 0.000 claims abstract description 60
- 230000003009 desulfurizing effect Effects 0.000 claims abstract description 27
- 239000007789 gas Substances 0.000 claims abstract description 27
- 239000007787 solid Substances 0.000 claims description 41
- UKLNMMHNWFDKNT-UHFFFAOYSA-M sodium chlorite Chemical compound [Na+].[O-]Cl=O UKLNMMHNWFDKNT-UHFFFAOYSA-M 0.000 claims description 34
- 229960002218 sodium chlorite Drugs 0.000 claims description 34
- 239000003795 chemical substances by application Substances 0.000 claims description 33
- 238000006243 chemical reaction Methods 0.000 claims description 31
- 238000005507 spraying Methods 0.000 claims description 27
- 239000000243 solution Substances 0.000 claims description 24
- 239000005708 Sodium hypochlorite Substances 0.000 claims description 20
- SUKJFIGYRHOWBL-UHFFFAOYSA-N sodium hypochlorite Chemical compound [Na+].Cl[O-] SUKJFIGYRHOWBL-UHFFFAOYSA-N 0.000 claims description 20
- 229910052979 sodium sulfide Inorganic materials 0.000 claims description 20
- GRVFOGOEDUUMBP-UHFFFAOYSA-N sodium sulfide (anhydrous) Chemical compound [Na+].[Na+].[S-2] GRVFOGOEDUUMBP-UHFFFAOYSA-N 0.000 claims description 20
- 239000007921 spray Substances 0.000 claims description 16
- 238000010521 absorption reaction Methods 0.000 claims description 15
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 15
- 239000011259 mixed solution Substances 0.000 claims description 14
- 239000002002 slurry Substances 0.000 claims description 11
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 claims description 10
- 239000000920 calcium hydroxide Substances 0.000 claims description 9
- 229910001861 calcium hydroxide Inorganic materials 0.000 claims description 9
- 235000011116 calcium hydroxide Nutrition 0.000 claims description 9
- 238000007599 discharging Methods 0.000 claims description 8
- 230000008021 deposition Effects 0.000 claims description 7
- 239000002245 particle Substances 0.000 claims description 7
- 238000012545 processing Methods 0.000 claims description 6
- 230000001276 controlling effect Effects 0.000 claims description 5
- 230000001105 regulatory effect Effects 0.000 claims description 5
- 238000009827 uniform distribution Methods 0.000 claims description 4
- 238000005452 bending Methods 0.000 claims description 2
- 238000009826 distribution Methods 0.000 claims description 2
- 230000010354 integration Effects 0.000 claims description 2
- 238000000926 separation method Methods 0.000 claims description 2
- 238000000746 purification Methods 0.000 abstract description 14
- 239000003344 environmental pollutant Substances 0.000 abstract description 6
- 231100000719 pollutant Toxicity 0.000 abstract description 6
- 239000002956 ash Substances 0.000 description 67
- 239000011575 calcium Substances 0.000 description 35
- 239000007788 liquid Substances 0.000 description 26
- 238000005243 fluidization Methods 0.000 description 20
- 238000012360 testing method Methods 0.000 description 12
- 230000000694 effects Effects 0.000 description 10
- 239000012535 impurity Substances 0.000 description 10
- 239000000463 material Substances 0.000 description 9
- 238000005516 engineering process Methods 0.000 description 8
- 239000007800 oxidant agent Substances 0.000 description 8
- 230000001590 oxidative effect Effects 0.000 description 8
- 238000003860 storage Methods 0.000 description 8
- 239000000779 smoke Substances 0.000 description 7
- 238000002360 preparation method Methods 0.000 description 6
- 230000002745 absorbent Effects 0.000 description 5
- 239000002250 absorbent Substances 0.000 description 5
- 238000007254 oxidation reaction Methods 0.000 description 5
- 230000002378 acidificating effect Effects 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 4
- 239000003814 drug Substances 0.000 description 4
- 230000003647 oxidation Effects 0.000 description 4
- 239000002351 wastewater Substances 0.000 description 4
- 239000002253 acid Substances 0.000 description 3
- 238000007664 blowing Methods 0.000 description 3
- 239000003054 catalyst Substances 0.000 description 3
- 230000007613 environmental effect Effects 0.000 description 3
- 230000002349 favourable effect Effects 0.000 description 3
- -1 ClO 2 - Chemical class 0.000 description 2
- 239000004734 Polyphenylene sulfide Substances 0.000 description 2
- 210000000988 bone and bone Anatomy 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 238000002485 combustion reaction Methods 0.000 description 2
- 238000009833 condensation Methods 0.000 description 2
- 230000005494 condensation Effects 0.000 description 2
- 238000005260 corrosion Methods 0.000 description 2
- 230000007797 corrosion Effects 0.000 description 2
- 238000005034 decoration Methods 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 239000010881 fly ash Substances 0.000 description 2
- 150000008040 ionic compounds Chemical class 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 229920000069 polyphenylene sulfide Polymers 0.000 description 2
- 230000002035 prolonged effect Effects 0.000 description 2
- VWDWKYIASSYTQR-UHFFFAOYSA-N sodium nitrate Chemical compound [Na+].[O-][N+]([O-])=O VWDWKYIASSYTQR-UHFFFAOYSA-N 0.000 description 2
- 239000004071 soot Substances 0.000 description 2
- 230000002195 synergetic effect Effects 0.000 description 2
- 238000012546 transfer Methods 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
- BZSXEZOLBIJVQK-UHFFFAOYSA-N 2-methylsulfonylbenzoic acid Chemical compound CS(=O)(=O)C1=CC=CC=C1C(O)=O BZSXEZOLBIJVQK-UHFFFAOYSA-N 0.000 description 1
- UXVMQQNJUSDDNG-UHFFFAOYSA-L Calcium chloride Chemical compound [Cl-].[Cl-].[Ca+2] UXVMQQNJUSDDNG-UHFFFAOYSA-L 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 1
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 description 1
- 239000002202 Polyethylene glycol Substances 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 235000011941 Tilia x europaea Nutrition 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 238000010669 acid-base reaction Methods 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000003044 adaptive effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 239000010882 bottom ash Substances 0.000 description 1
- 239000001110 calcium chloride Substances 0.000 description 1
- 229910001628 calcium chloride Inorganic materials 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000005536 corrosion prevention Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000003500 flue dust Substances 0.000 description 1
- 239000002803 fossil fuel Substances 0.000 description 1
- XLYOFNOQVPJJNP-ZSJDYOACSA-N heavy water Substances [2H]O[2H] XLYOFNOQVPJJNP-ZSJDYOACSA-N 0.000 description 1
- 229910000037 hydrogen sulfide Inorganic materials 0.000 description 1
- 239000004571 lime Substances 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 239000005416 organic matter Substances 0.000 description 1
- 229920001223 polyethylene glycol Polymers 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 238000010791 quenching Methods 0.000 description 1
- 239000000376 reactant Substances 0.000 description 1
- 238000010992 reflux Methods 0.000 description 1
- 238000003303 reheating Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 239000002893 slag Substances 0.000 description 1
- 238000009751 slip forming Methods 0.000 description 1
- 235000010344 sodium nitrate Nutrition 0.000 description 1
- 239000004317 sodium nitrate Substances 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 230000005514 two-phase flow Effects 0.000 description 1
- 239000002912 waste gas Substances 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D46/00—Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
- B01D46/02—Particle separators, e.g. dust precipitators, having hollow filters made of flexible material
- B01D46/023—Pockets filters, i.e. multiple bag filters mounted on a common frame
-
- 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
- B01D53/46—Removing components of defined structure
- B01D53/48—Sulfur compounds
- B01D53/50—Sulfur oxides
- B01D53/501—Sulfur oxides by treating the gases with a solution or a suspension of an alkali or earth-alkali or ammonium compound
- B01D53/502—Sulfur oxides by treating the gases with a solution or a suspension of an alkali or earth-alkali or ammonium compound characterised by a specific solution or suspension
-
- 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
- B01D53/46—Removing components of defined structure
- B01D53/54—Nitrogen compounds
- B01D53/56—Nitrogen oxides
-
- 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
- B01D53/77—Liquid phase processes
- B01D53/78—Liquid phase processes with gas-liquid contact
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Health & Medical Sciences (AREA)
- Biomedical Technology (AREA)
- Analytical Chemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Treating Waste Gases (AREA)
Abstract
The invention discloses a semi-dry ion denitration, desulfurization and dust removal integrated treatment device, which comprises: the flue system comprises a primary desulfurization system and an ion denitration system which are sequentially arranged in the flue along the flow direction of flue gas; the secondary desulfurization system is arranged at the downstream of the flue system; the secondary desulfurization system comprises a Venturi tube and a desulfurization tower, wherein the gas inlet section of the Venturi tube is communicated with the tail end of the flue system, and the gas outlet section of the Venturi tube is communicated with the inside of the desulfurization tower; the dust remover is communicated with the exhaust port of the desulfurizing tower; the exhaust end of the dust remover is connected with the clean flue gas recirculation system; the dust collecting end of the dust remover is connected to the air inlet section of the venturi tube through a circulating ash system. The invention also provides a corresponding process. Therefore, the denitration unit can be liberated from the rest of the boiler, so that the desulfurization, denitrification and dust removal are operated in the same temperature window, the desulfurization and denitrification cost is greatly reduced, the deep purification of denitration, desulfurization and dust removal is realized, and the standard reaching and even ultra-clean emission of all pollutants is achieved.
Description
Technical Field
The invention belongs to the technical field of flue gas desulfurization, denitrification and dedusting purification, particularly relates to a deep purification technology of waste gas generated in a boiler combustion process, and particularly relates to a semi-dry ion denitration, desulfurization and dedusting integrated treatment device and process.
Background
the fossil fuel combustion flue gas is often accompanied with the emission of pollutants such as NOx, SOx, dust and the like, and the flue gas is often purified industrially through a multi-technology combined process due to different removal principles of the three types of pollutants. In the prior art, particularly in the design of the purification process of large-scale flue gas, the denitration unit, the desulfurization unit and the dust removal unit are often connected in series.
the method is characterized in that the flue gas desulfurization generally adopts an alkaline absorbent to circularly spray and is in countercurrent contact with the flue gas to absorb SO 2 in the flue gas, wherein the petrochemical wet desulfurization refers to a method of adopting alkaline absorption liquid or slurry as an absorbent, the semi-dry desulfurization refers to a method of adopting solid particles as an absorbent, and the dust removal technology is mainly realized by adopting a filtering method, the SCR denitration temperature is 300-400 ℃, the SCR denitration temperature needs to be placed between a superheater and high-temperature water gas in a residual boiler, namely SCR denitration, and desulfurization and dust removal are carried out after the residual boiler.
the wet desulphurization temperature is between 50 and 60 ℃, and the corresponding flue gas dedusting temperature is 160 to 180 ℃; the operation temperature of the semi-dry desulfurization is 80-100 ℃, and the dust removal temperature range matched with the operation temperature is 80-100 ℃.
Compared with wet desulphurization, the existing semi-dry desulphurization technology has the advantages of no generation of white smoke, blue smoke, wastewater and the like, and the desulphurization and the dust removal are integrally operated, but the desulphurization and the dust removal are still in different operation intervals with SCR denitration, and the purification of the smoke gas can be completed by two completely independent units.
chinese patent document CN 109529621A discloses a semi-dry desulfurization, denitrification and demercuration method based on catalytic oxidation and deep condensation, wherein NO X 2 and Hg in flue gas after dust removal generate NO 3- , SO 4 2- and Hg 2+ under the synergistic effect of O 3/H 2 O 2 and a catalyst, then the deep removal of pollution components in the flue gas is realized by multi-stage condensation, and the purified flue gas is treated by demisting and reheating processes and then is discharged into the environment.
Chinese patent document CN 208082211U proposes an efficient integrated device for denitration, desulfurization and dust removal by semidry method, which comprises an absorption tower and a bag-type dust remover, wherein flue gas enters the absorption tower from the lower part of the tower, and after being discharged from the upper part of the tower, the flue gas enters the dust remover, a process water nozzle and an oxidant solution nozzle are arranged in the absorption tower, the process water nozzle is arranged at the lower part of the tower, the oxidant solution nozzle is arranged at the upper part of the tower, and a height difference is formed in the vertical direction, so that the partitioned control of firstly performing desulfurization and then performing denitration is realized. The collected dust of the dust collector is returned to the lower part of the absorption tower and is discharged from the bottom of the absorption tower. Although the patent technology has the advantages of reducing the consumption of high-cost oxidant and shortening the flow, the collected dust is returned to the upper part of the flue gas inlet at the lower part of the absorption tower and is easy to be carried upwards by flue gas, so that the accumulation of ineffective absorbent in a system is caused, the absorption efficiency is reduced, the load of the dust remover is increased, the standard exceeding of discharged flue gas and dust is easy to cause, and the service life of the dust remover is shortened. And the variety of the oxidant is variable, the oxidation effect and adaptability of most oxidants are influenced by temperature and humidity, and if the oxidant with a determined formula and a determined proportion is not adopted, the uncertain factors of a system, such as serious equipment corrosion, high operation cost, influence on system stability and the like, can be caused.
Chinese patent document CN 109200782a proposes a semi-dry desulfurization and denitrification process for high-concentration organic flue gas, wherein flue gas is cooled by a condensing tower and then enters a desulfurization and denitrification tower for treatment, and the treated flue gas is subjected to dust removal and purification and then is discharged after reaching the standard. In the desulfurization and denitrification tower, the flue gas is firstly sprayed by lime water and then sprayed by the desulfurization and denitrification catalyst, and the sprayed flue gas enters active carbon for adsorption. Although this technique is favorable to retrieving the organic matter, because quench tower is in wet-type acid environment, it is serious to corrode, and catalyst denitration is serious to the temperature dependence moreover, and is with high costs, output SOx/NOx control waste water.
Chinese patent document CN 107497273a proposes a preparation method and application of an environment-friendly low-cost flue gas denitration agent, which adopts a denitration solution prepared from sodium chlorate, polyethylene glycol, sodium nitrate, calcium chloride and a certain amount of acid. The proportioning needs to be carried out under an acidic condition, the used PH environment is high, and the proportioning medicament is complex, so that the cost of the medicament is not substantially reduced.
Aiming at the defects of the existing semi-dry desulfurization, denitrification and dedusting integrated technology, the invention needs to provide a semi-dry ion denitrification, desulfurization and dedusting integrated treatment device and process, which can liberate a denitrification unit from the rest of a pot, enable desulfurization, denitrification and dedusting to operate in the same temperature window, greatly reduce the desulfurization and denitrification cost, realize deep purification of denitrification, desulfurization and dedusting, and achieve the purpose that all pollutants reach the standard and even are discharged in an ultra-clean manner.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides the integrated treatment device and the process for the ion denitration, desulfurization and dust removal by the semidry method, which can realize deep purification of denitration, desulfurization and dust removal, are energy-saving and environment-friendly, reduce the cost and operate stably and reliably. The device and the corresponding process can liberate the denitration unit from the residual pot, so that the desulfurization, denitration and dust removal are operated in the same temperature window, and the expensive conventional oxidant is replaced by the low-price ionic compound, so that the desulfurization and denitration cost is greatly reduced through a certain medicament proportion. Therefore, in a set of device system, the circulating fluidized bed is used as a reaction foundation bed, deep purification of denitration, desulfurization and dust removal is realized simultaneously, and all pollutants reach the standard and are even discharged in an ultra-clean manner.
in order to realize one of the purposes, the invention provides an integrated treatment device for ion denitration, desulfurization and dust removal by a semidry method, which adopts the following technical scheme:
The utility model provides a semidry method ion denitration desulfurization dust removal integration processing apparatus, includes:
The flue system comprises a primary desulfurization system and an ion denitration system which are sequentially arranged in a flue along the flow direction of flue gas;
the secondary desulfurization system is arranged at the downstream of the flue system; the secondary desulfurization system comprises a Venturi tube and a desulfurization tower, wherein the gas inlet section of the Venturi tube is communicated with the tail end of the flue system, and the gas outlet section of the Venturi tube is communicated with the inside of the desulfurization tower;
The dust remover is communicated with the exhaust port of the desulfurizing tower; one path of the exhaust end of the dust remover is connected with a clean flue gas exhaust pipeline, and the clean flue gas exhaust pipeline is connected into a flue system through a clean flue gas recirculation flue and an electric switch regulating valve to form a clean flue gas recirculation system; the dust collecting end of the dust remover is connected to the air inlet section of the venturi tube through a circulating ash system.
Preferably, the flue comprises a horizontal section and a bent section; the primary desulfurization system and the ion denitration system are sequentially arranged in the horizontal section and are connected with the Venturi tube through the bent connection section; and/or the presence of a gas in the gas,
The bottom of the flue is provided with an ash deposition bucket which is communicated with the flue, and the ash deposition bucket is respectively arranged under the air inlet section of the corresponding Venturi tube and under the primary desulfurization system and the ion denitration system.
Furthermore, the bending section between the ion denitration system and the Venturi tube is also provided with an air flow uniform distribution device.
preferably, the primary desulfurization system comprises a double-reflux spray gun with the spray opening facing into the flue and used for spraying Ca (OH) 2 slurry to react with the flue gas, and/or,
The ion denitration system comprises double backflow spray guns, and spray ports of the double backflow spray guns face the interior of the flue and are used for spraying ion denitration agents to react with flue gas.
preferably, the air outlet section of the venturi tube is an outlet expanding pipe section, and a water spraying device facing the inside of the desulfurization tower is arranged in the outlet expanding pipe section and used for reducing the smoke temperature in the desulfurization tower.
preferably, the dust remover adopts a long-bag low-pressure pulse dust remover.
preferably, the circulating ash system comprises a material returning and discharging unit, the material returning and discharging unit comprises an air fluidization conveying groove, a fluidization bottom bin, a middle ash bin, an air chute and a pneumatic conveying device, and the pneumatic conveying device comprises a bin pump;
The inlet of the air fluidization conveying groove is communicated with the dust collecting end of the dust remover through a pipeline, and a material returning control valve is arranged on the pipeline and used for receiving dust collected in the dust remover; the outlet of the air fluidization conveying groove is connected with the fluidization bottom bin, and the fluidization bottom bin is provided with a plurality of fluidization fan inlets for keeping the fluidization state of the fly ash in the fluidization bottom bin; an overflow port of the fluidized bottom bin is communicated to an intermediate ash bin, the intermediate ash bin is connected to an ash storage bin through a bin pump, and a discharge control valve is arranged between the intermediate ash bin and the bin pump and used for conveying ash to the ash storage bin for storage through pneumatic force; and a circulating ash outlet pipeline of the fluidized bottom bin is connected to the air inlet section of the Venturi tube through an air chute, and an electric flow control valve is arranged on the circulating ash outlet pipeline.
The invention also aims to provide a semi-dry ion denitration, desulfurization and dust removal integrated treatment process, which comprises the following steps:
s1, introducing the flue gas to be treated from the flue, and preliminarily reacting most of SO 2 in the flue gas with Ca (OH) 2 solution by spraying slaked lime slurry at the first section of the inlet flue of the desulfurizing tower;
s2, spraying an ion denitration agent at the second section of the inlet flue of the desulfurization reactor to convert NO in the flue gas into NO 2;
s3, accelerating the flue gas to enter a circulating fluidized bed in a desulfurizing tower for secondary desulfurization through a venturi tube, spraying process water into the tower through a water spraying device above the venturi tube, reducing the temperature of the flue gas in the desulfurizing tower to about 75-85 ℃, converting the reaction of SO 2 and Ca (OH) 2 into an instantaneously finished ionic reaction, and humidifying and atomizing Ca (OH) 2 (solid) which is carried in the flue gas and has not been subjected to the reaction and CaO (solid) contained in CaSO 3 (solid) and CaSO 4 (solid);
the purified dust-containing flue gas is discharged from the top of the desulfurizing tower and then enters a dust remover for gas-solid separation, solid particles collected by the dust remover return to the absorption tower through a circulating ash system at the downstream of the dust remover to continuously participate in the reaction, and the circulation is carried out, wherein unreacted solid Ca (OH) 2 in the ash removed by the dust remover and solid Ca (OH) 2 contained in solid CaSO 3 and CaSO 4 circulate to the desulfurizing tower along with the circulating ash to continuously react, and the redundant small amount of desulfurization and denitrification ash is discharged;
And S4, discharging the treated flue gas reaching the standard.
preferably, in step S2, the ion denitration agent is a mixed solution of sodium chlorite, sodium hypochlorite and sodium sulfide, and the molar ratio of the sodium chlorite to the sodium hypochlorite to the sodium sulfide is (1-4): (2-6): (1.5-3). Wherein, the sodium chlorite adopts 15-30 wt% sodium chlorite solution in the preparation process.
Further, the mole ratio of sodium chlorite, sodium hypochlorite and sodium sulfide in the ionic denitration agent is 2: 4: 2.
Preferably, in step S1, the molar ratio of the Ca element to the S element in the flue gas is controlled to be (1-3): 1.
preferably, in step S2, the reaction temperature for denitration of the reactive ions is controlled to be 50 to 100 ℃.
Preferably, in step S3, the flue gas is accelerated into the desulfurization tower through the gas flow distributor and then enters the venturi tube.
The invention can bring the following beneficial effects:
1. the invention provides a semi-dry ion denitration, desulfurization and dust removal integrated treatment device and a process technology, which can liberate a denitration unit from a residual pot, enable desulfurization, denitration and dust removal to operate in the same temperature window, and improve the convenience and treatment efficiency of operation; and the cheap ionic compound is used for replacing the expensive oxidant, so that the desulfurization and denitrification cost is greatly reduced through a certain medicament proportion. Therefore, in a set of device system, the circulating fluidized bed is used as a reflecting foundation bed, and the deep purification of denitration, desulfurization and dust removal is realized simultaneously, so that all pollutants reach the standard and are even discharged in an ultra-clean manner.
2. the method adopts a special mixed solution as an ion denitration agent, generates ions such as ClO 2 - , ClO - , Cl - , NO 2 - , NO 3 - and the like before and after reaction, wherein the relative electrode electromotive force of ClO 2 - /ClO - electrons in the mixed denitration agent solution is 1.645, and the electromotive force is stronger than that of any single ion, so the oxidability of the mixed denitration agent solution is further improved, and the required dosage of the mixed denitration agent solution is half saved.
3. The temperature of the ion denitration system is controlled to be within the optimal range of 50-100 ℃, and because the system device adopts secondary desulfurization and wet denitration, and the temperature of high-temperature flue gas can be reduced by 60% after the high-temperature flue gas is washed by slaked lime solution in the primary desulfurization system, the device and the process can meet the high-temperature flue gas treatment requirement of 200 ℃ at most, and have excellent temperature adaptability of 50-200 ℃. Meanwhile, the humidity adaptive capacity is excellent, and the method is suitable for the flue gas humidity of 4% -20%.
4. The whole set of treatment device of the invention does not generate waste water and does not need to be added with the investment of a waste water treatment system.
5. The outlet flue gas is at the environmental dew point of more than 15-20 ℃, no colored rain or smoke is generated, no white removing device is required to be additionally arranged, and the investment is reduced. And the flue material adopts conventional Q235, and is anticorrosive without the scale, so can bear the flue gas of higher temperature and pass through to whole device need not the scale anticorrosive, reduces the investment.
6. The invention can adjust the flow load of the flue gas at the inlet of the system by designing the clean flue gas recirculation system, so that the load of the system is stable.
In conclusion, the device and the process for integrated treatment of desulfurization, denitrification and dust removal realize that the denitration efficiency is more than or equal to 95%, the desulfurization efficiency is more than or equal to 95% and the dust removal efficiency is more than or equal to 99% on the basis of reducing the cost and having stable and high device operation reliability.
drawings
The above features, technical features, advantages and modes of realisation of the present invention will be further described in the following detailed description of preferred embodiments thereof, which is to be read in connection with the accompanying drawings.
FIG. 1 is a schematic structural diagram of a semi-dry ion denitration desulfurization dust removal integrated treatment device;
The reference numbers illustrate:
1-flue system, 10-flue, 11-first-stage desulfurization system, 12-ion denitration system and 13-airflow uniform distribution device;
2-a secondary desulfurization system, 21-a venturi tube, 210-an air inlet section, 211-an outlet expanding section, 212-a water spraying device and 22-a desulfurization tower;
3-a dust remover, 30-a clean flue gas discharge pipeline, 31-a clean flue gas recirculation flue and 32-an electric switch regulating valve;
4-circulating ash system, 40-intermediate ash bin.
Detailed Description
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following description will be made with reference to the accompanying drawings. It is obvious that the drawings in the following description are only some examples of the invention, and that for a person skilled in the art, other drawings and embodiments can be derived from them without inventive effort.
for the sake of simplicity, the drawings only schematically show the parts relevant to the present invention, and they do not represent the actual structure as a product.
example 1
as shown in fig. 1, a semi-dry ion denitration, desulfurization and dust removal integrated treatment device comprises:
The flue system 1 comprises a primary desulfurization system 11 and an ion denitration system 12 which are sequentially arranged in a flue 10 along the flow direction of flue gas;
the secondary desulfurization system 2 is arranged at the downstream of the flue system 1; the secondary desulfurization system 2 comprises a Venturi tube 21 and a desulfurization tower 22, wherein the air inlet section of the Venturi tube 14 is communicated with the tail end of the flue system 1, and the air outlet section of the Venturi tube is communicated with the inside of the desulfurization tower 22;
The dust remover 3 is communicated with the top exhaust port of the desulfurizing tower 22 in the side direction; one path of the exhaust end of the dust remover 3 is connected with a clean flue gas exhaust pipeline 30, and the clean flue gas exhaust pipeline 30 is connected to a flue system through a clean flue gas recirculation flue 31 and an electric switch regulating valve 32 to form a clean flue gas recirculation system; the dust collecting end of the dust separator 3 is connected to the air inlet section 210 of the venturi tube 21 through the circulating ash system 4.
in the embodiment, waste flue gas firstly enters a flue to be treated by a primary desulfurization system 11 and an ion denitration system 12, then enters a circulating fluidized bed body in a desulfurization tower 2 through a Venturi tube 21 to be accelerated to carry out secondary desulfurization treatment, gas-solid two phases are turbulent and mixed under the action of airflow and fully contact, floccules are continuously formed to return downwards (internal circulation) in the rising process, and the floccules are continuously disintegrated and lifted by the airflow again in the turbulent motion, SO that SO 2 in the bed is fully reacted, the gas-solid two-phase flow mechanism in the circulating fluidized bed greatly strengthens mass transfer and heat transfer between the gas and the solid, SO as to provide fundamental guarantee for realizing high desulfurization rate, then, the fully desulfurized flue gas enters a dust remover to be dedusted and then returns to the desulfurization tower through a circulating ash system to be subjected to circulating reaction continuously, the utilization rate and desulfurization efficiency of an absorbent Ca (OH) 2 are improved, the normal operation of the deacidification system is guaranteed, in addition, no waste water is generated, the flue gas flow rate at the inlet of the flue of the clean flue gas recirculation 31 can be adjusted, the load of the system is stable, the denitration system, the ion denitration device and the denitration device can meet the highest flue gas temperature of the secondary desulfurization and the flue gas washing temperature of 100-removing lime by a wet method, SO as to meet the highest flue gas washing temperature of the highest flue gas.
as a preferred embodiment, the flue 10 includes a horizontal section and a bent section, and the primary desulfurization system 11 and the ion denitration system 12 are sequentially disposed in the horizontal section and are connected to the venturi tube 14 (vertically disposed with the desulfurization tower) through the bent section. In practical application, the flue is made of conventional Q235 steel, and scale-free corrosion prevention is realized, so that the flue can bear the passing of smoke at a higher temperature. Preferably, the curved connection section between the ion denitration system 12 and the venturi tube 21 is further provided with an airflow uniform distribution device 13, so that the flue gas can more uniformly enter the desulfurization tower 2. Preferably, the bottom of the flue 10 is provided with an ash deposition hopper 100 (which can be in a through hole form), the ash deposition hopper 100 is respectively arranged right below the air inlet section 210 of the corresponding venturi tube 21 and right below the primary desulfurization system 11 and the ion denitration system 12, and the ash deposition hopper 100 is communicated with the flue 10; the ash bucket can be used for receiving part of circulating ash which does not enter the desulfurization tower and part of falling ash after desulfurization and denitrification reaction.
As another preferred embodiment, the primary desulfurization system 11 comprises a dual-flow-back spray gun, the spraying openings of which face the flue 10 and are used for spraying Ca (OH) 2 slurry to react with the flue gas, and more preferably, the primary desulfurization system 11 also comprises an oxidizing air pipeline facing the flue 10 and used for promoting the sufficient oxidation reaction of the Ca (OH) 2 slurry and the flue gas.
As another preferred embodiment, the ion denitration system 12 includes a dual-flow-back spray gun, the spray opening of which faces into the flue system for spraying the ion denitration agent to react with the flue gas.
as another preferred embodiment, the outlet section of the venturi tube 21 is an outlet expanding section 211, and a water spraying device 212 facing the inside of the desulfurization tower 2 is arranged in the outlet expanding section 211 for reducing the smoke temperature in the desulfurization tower 2.
In the above embodiment, the dust remover 3 is a long bag low pressure pulse dust remover. More preferably, a long-bag low-pressure pulse dust collector is adopted, and the LDMC-II series long-bag low-pressure pulse dust collector is purchased from Liaoning Vast environmental protection equipment engineering Limited company; the dust remover comprises an upper box body, a middle box body, an inlet and outlet flue, a dust hopper, a compressed air back-blowing system, a filter bag, a bag and a control system, wherein when the dust remover works, dust-containing flue gas enters the dust hopper from the inlet flue, large-particle dust directly falls into the bottom of the dust hopper, finer dust uniformly enters the middle box body and is adsorbed on the outer surface of the filter bag, and purified clean flue gas enters the upper box body through the filter bag and is discharged (an exhaust end) through the outlet flue; the dust on the outer surface of the filter bag is continuously increased along with the continuous filtration, when the resistance of the equipment reaches a limited resistance value, the compressed air back blowing system automatically works according to a pressure difference set value or an ash removal time set value in the control system, the pressure in the filter bag is suddenly increased by utilizing the instantaneous back blowing of the compressed air, the dust on the surface of the filter bag is removed, and the dust on the filter bag is shaken down to an ash hopper (dust collection end). Since the dust remover is the prior art in the field, further description of the structure and function of the dust remover is omitted here.
In the above embodiment, the circulating ash system 4 includes a material returning unit, the material returning unit includes an air fluidization conveying tank, a fluidization bottom bin, an intermediate ash bin 40, an air chute, and a pneumatic conveying device, the pneumatic conveying device includes a bin pump; the inlet of the air fluidization conveying groove is communicated with the dust collecting end of the dust remover through a pipeline, and a material returning control valve is arranged on the pipeline and used for receiving dust collected in the dust remover; the outlet of the air fluidization conveying groove is connected with the fluidization bottom bin, and the fluidization bottom bin is provided with a plurality of fluidization fan inlets for keeping the fluidization state of the fly ash in the fluidization bottom bin; an overflow port of the fluidized bottom bin is communicated to an intermediate ash bin, the intermediate ash bin is connected to an ash storage bin through a bin pump, and a discharge control valve is arranged between the intermediate ash bin and the bin pump and used for conveying ash to the ash storage bin for storage through pneumatic force; and a circulating ash outlet pipeline of the fluidized bottom bin is connected to the air inlet section of the Venturi tube through an air chute, and an electric flow control valve is arranged on the circulating ash outlet pipeline.
therefore, when the material returning control valve (not shown in the figure) is opened, all the ash collected in the ash hopper of the dust remover 3 enters the fluidized bottom bin (not shown in the figure) through the air fluidized conveying groove (not shown in the figure) in the circulating ash system, and the ash is controlled at a certain material level in the fluidized bottom bin to ensure that the ash amount is enough to meet the circulating requirement; one part of the fluidization bottom bin is used for discharging ash outside, overflows into the middle ash bin 40, and is pneumatically conveyed to the ash storage bin by the bin pump to be discharged outside after a discharge control valve (not shown in the figure) is opened; most of the rest ash in the fluidized bottom bin is used as circulating ash, is sent into an air chute (not shown in the figure) through an electric flow control valve and then is sent into a venturi tube to enter a desulfurization tower for circulation, the circulating ash has good fluidity, and the amount of the circulating ash can be adjusted through the flow control valve; the removal efficiency of the acid gas is ensured by adjusting the amount of circulating ash, and simultaneously, the good and stable operation of the system is ensured. Since the circulating ash system is conventional in the art, further description of the structure and function thereof is omitted here.
example 2
The embodiment is an integrated treatment process for ion denitration, desulfurization and dust removal by a semidry method, which is shown in fig. 1 and comprises the following steps:
S1, introducing the flue gas to be treated from the flue 10 at the inlet of the desulfurization tower 2, and spraying slaked lime slurry at the first section of the flue 10 to primarily cause most of SO 2 in the flue gas to have a primary desulfurization reaction with Ca (OH) 2 solution, wherein the reaction equation is as follows:
SO 2 (gas) + H 2 O → H 2 SO 3 (liquid);
ca (OH) 2 (liquid) + H 2 SO 3 (liquid) → CaSO 3 (liquid) +2H 2 O
CaSO 3 (liquid) +1/2O 2 (liquid) → CaSO 4 (liquid)
S2, converting NO in the flue gas into NO 2 by spraying an ion denitration agent at the second section of the flue 10, wherein the reaction equation is as follows:
4NO+3NaClO2+2H2O→4HNO3+3NaCl；
2NO+3NaClO+H2O→3NaCl+2HNO3；
4NO 2 (gas) +2H 2 O + O 2 (gas) → 4HNO 3 (liquid)
s3, accelerating the flue gas to enter a circulating fluidized bed in a desulfurizing tower 2 through a venturi tube 21 for secondary desulfurization reaction, and simultaneously spraying process water into the tower through a water spraying device 212 of an outlet expansion section 211 of the venturi tube 21 to reduce the temperature of the flue gas in the desulfurizing tower 2 to about 75-85 ℃ (higher than the dew point of the flue gas by 20 ℃) SO as to convert the reaction between SO 2 and Ca (OH) 2 into ionic reaction which can be completed instantly, and humidifying and atomizing Ca (OH) 2 (solid) which is carried in the flue gas and CaO (solid) contained in CaSO 3 (solid) and CaSO 4 (solid) to restore the absorption capacity;
the solid particles collected by the dust remover 3 return to the desulfurizing tower 2 through a circulating ash system 4 at the downstream of the dust remover 3 to continue to react, wherein unreacted Ca (OH) 2 (solid) and Ca (OH) 2 (solid) contained in CaSO 3 (solid) and CaSO 4 (solid) in the soot removed by the dust remover are circulated into the desulfurizing tower to continue to react, and the excessive small amount of desulfurized and denitrified ash slag is conveyed into an ash storage bin through pneumatic transmission to be discharged outside and circulated;
the reaction equation is:
SO 2 (gas) + H 2 O → H 2 SO 3 (liquid)
4NO 2 (gas) +2H 2 O + O 2 (gas) → 4HNO 3 (liquid)
Ca (OH) 2 (liquid) + H 2 SO 3 (liquid) → CaSO 3 (liquid) +2H 2 O
Ca (OH) 2 (solid) + H 2 SO 3 (liquid) → CaSO 3 (liquid) +2H 2 O
ca (OH) 2 (liquid) +2HNO 3 (liquid) → Ca (NO 3) 2 (liquid) +4H 2 O
Ca (OH) 2 (solid) +2HNO 3 (liquid) → Ca (NO 3) 2 (liquid) +4H 2 O
CaSO 3 (liquid) +1/2O 2 (liquid) → CaSO 4 (liquid)
CaSO 4 (liquid) → CaSO 4 (solid)
Ca (NO 3) 2 (liquid) → Ca (NO 3) 2 (solid)
And S4, discharging the treated flue gas reaching the standard into a chimney through a draught fan.
in the embodiment, the waste flue gas firstly enters a flue and is subjected to primary desulfurization treatment and ion denitration treatment, then is accelerated by a venturi tube 21 to enter a circulating fluidized bed body in a desulfurization tower for secondary desulfurization treatment, and then is subjected to dust removal treatment, and most of solid particles collected after the dust removal treatment are returned to the desulfurization tower as circulating ash to continue absorption reaction; therefore, the process realizes the high-efficiency integrated treatment of desulfurization, denitrification and dust removal in the same temperature window. In addition, the device adopts two-stage desulfurization and wet-process ion denitration, the temperature of the high-temperature flue gas can be reduced by 60% after the high-temperature flue gas is washed by the first-stage slaked lime solution, and the optimal temperature of the denitration section is 50-100 ℃, so that the high-temperature flue gas can meet the treatment requirement of 200 ℃ at most.
the method comprises the following steps of S3, enabling circulating ash collected by a dust collector to participate in conversion reaction, wherein the dust collector adopted in the embodiment is not a bag-type dust collector commonly used in the prior art, preferably a long-bag low-pressure pulse dust collector, and is an LDMC-II series long-bag low-pressure pulse dust collector from Liaoning Ming-justice environmental protection equipment engineering Limited company, when a semi-dry method is adopted, a filter bag is required to be in contact with acidic gas in flue gas and alkaline reactant, a PPS (polyphenylene sulfide) film-coated filter bag is preferably selected under the condition, the shortest service life is 30 months, the actual service life can be fully prolonged according to the maintenance experience and management level of a user and can reach more than 4 years at most, moreover, the cage bones of the dust collector are subjected to surface spraying by adopting organic silicon high-temperature coating, the corrosion of the cage bones can be effectively prevented, the service life is prolonged, the discharge concentration of an outlet of the dust collector is controlled to be always less than 15mg/Nm 3, the discharge concentration of the air is controlled to be always controlled by an air fluidization conveying groove in a fluidized bottom bin, the circulating ash hopper, the circulating system, the circulating ash is further, the circulating ash flow rate of the circulating ash is ensured, the circulating air, the circulating ash is ensured by the conventional circulating system, the conventional circulating ash flow control, the conventional circulating system, the fluidized bottom ash flow control technology, the flow control of the conventional circulating ash flow control, the.
in a preferred embodiment, the molar ratio of Ca element to S element in step S1 is controlled to 1: 1. Tests prove that the control in the proportion range is favorable for coordinating the synergistic effect of the primary desulfurization reaction and the secondary desulfurization reaction, the consumption of slaked lime can be reduced, the acid-base reaction can be fully reacted to the maximum extent, the desulfurization process of the whole system is promoted to be carried out efficiently, and the desulfurization efficiency is finally realized to be more than or equal to 95%.
In a preferred embodiment, the ionic denitration agent is a mixed solution of sodium chlorite, sodium hypochlorite and sodium sulfide, wherein the sodium chlorite component is preferably prepared by using a sodium chlorite solution with a concentration of 15-30 wt% in view of cost and safety. Preferably, the ionic denitration agent comprises sodium chlorite, sodium hypochlorite and sodium sulfide in a molar ratio of (1-4): (2-6): (1.5 to 3). More preferably, the molar ratio of sodium chlorite to sodium hypochlorite to sodium sulfide in the ionic denitration agent is respectively 2: 4: 2.
In the embodiment, a special mixed denitration agent solution is adopted, ions such as ClO 2 - , ClO - , Cl - , NO 2 - , NO 3 - and the like can be generated before and after reaction, the relative electrode electromotive force of ClO 2 - /ClO - electrons in the mixed denitration agent solution is 1.645, the electromotive force is stronger than that of any single ion, the oxidability of the mixed denitration agent solution is further improved, the required dosage of the mixed denitration agent solution is half saved with the same denitration effect, the electrode electromotive force has better effect under an acidic condition, sodium sulfide can be hydrolyzed into hydrogen sulfide under the acidic working condition of flue gas desulfurization and denitration, the activity and the electromotive force of ClO 2 - /ClO - are moderately improved, the formula is simple, the oxidation effect of the mixed denitration agent solution is further enhanced, and the ion denitration effect of the invention is excellent.
as another preferred embodiment, when the flue gas load is reduced according to different flue gas conditions, the electric switch regulating valve 32 on the clean flue gas recirculation flue 31 is opened to recirculate the clean flue gas into the desulfurizing tower 2, so that the inlet flue gas load of the desulfurizing tower 2 is maintained in a relatively stable state. Therefore, the integrated desulfurization, denitrification and dust removal device and the process are more stable in operation.
as another preferred embodiment, in step S3, the flue gas firstly passes through the gas flow distributor 13 and then enters the venturi tube 14 to accelerate into the desulfurization tower 2, which is favorable for the balance of the flue gas entering the desulfurization tower 2 for the secondary desulfurization reaction.
example 3
The embodiment is a semi-dry ion denitration, desulfurization and dust removal integrated treatment process, which comprises the following treatment steps:
s1, introducing flue gas to be treated from a flue 10 at an inlet of a desulfurizing tower 2 at a flow rate of 20m 3/h, wherein the temperature of the flue gas is 120 ℃, the initial SO 2 content in the flue gas is 2000mg/m 3, the initial NOx concentration is 500mg/m 3, and the initial dust concentration is 10g/m 3, spraying slaked lime slurry at the first section of the flue 10, controlling the molar ratio of Ca element to S element to be 2:1, and primarily leading most of SO 2 in the flue gas and Ca (OH) 2 solution to have primary desulfurization reaction;
S2, spraying an ion denitration agent on the second section of the flue 10, wherein the ion denitration agent is a mixed solution of sodium chlorite, sodium hypochlorite and sodium sulfide, the final concentration of the mixed solution is 2mmol/L of sodium chlorite, 4mmol/L of sodium hypochlorite and 2mmol/L of sodium sulfide, and in the preparation process, the sodium chlorite is a 20 wt% sodium chlorite solution to convert NO in flue gas into NO 2;
S3, continuously distributing the flue gas through the gas flow distribution device 13, controlling the liquid-gas ratio to be 20L/m 3, then entering the venturi tube 14 to accelerate the flue gas to enter a circulating fluidized bed in the desulfurizing tower 2 for secondary desulfurization reaction, simultaneously spraying process water into the tower through the water spraying device 142 of the outlet expansion section 141 of the venturi tube 14, on one hand, reducing the temperature of the flue gas in the desulfurizing tower 2 to be about 75-85 ℃ and higher than the dew point of the flue gas by more than 20 ℃, SO that the reaction of SO 2 and Ca (OH) 2 is converted into ionic reaction which can be completed instantly, on the other hand, Ca (OH) 2 (solid) which is not subjected to the reaction and is carried in the flue gas, and humidifying and atomizing CaO (solid) contained in CaSO 3 (solid) and CaSO 4 (solid), thereby recovering the absorption capacity;
The solid particles collected by the dust remover 3 return to the desulfurizing tower 2 through a circulating ash system 4 at the downstream of the dust remover 3 to continue to react, wherein unreacted Ca (OH) 2 (solid) and Ca (OH) 2 (solid) contained in CaSO 3 (solid) and CaSO 4 (solid) in the soot removed by the dust remover are circulated into the desulfurizing tower to continue to react, and the excessive small amount of desulfurized and denitrified ash is discharged outside, and the process is circulated;
and S4, discharging the treated flue gas reaching the standard into a chimney through a draught fan.
After 5 times of parallel tests, the average content of the standard-reaching flue gas is 80mg/m 3 of SO 2, 16mg/m 3 of NOx and 0.06g/m 3 of dust, and the NOx removal rate, the SO 2 removal rate and the dust removal rate are calculated to be 96.8%, 96% and 99.4%, respectively.
Example 4
The procedure of this example is substantially the same as example 3, except that:
In step S2, the ion denitration agent is a mixed solution of sodium chlorite, sodium hypochlorite, and sodium sulfide, and the final concentration of the mixed solution is: 1mmol/L of sodium chlorite, 2mmol/L of sodium hypochlorite and 1.5mmol/L of sodium sulfide, and in the preparation process, a 15 wt% sodium chlorite solution is adopted as the sodium chlorite.
After 5 times of parallel tests, the average impurity removal rate of the standard-reaching flue gas is 95.6 percent of NOx removal rate, 95 percent of SO 2 removal rate and 99.1 percent of dust removal rate.
comparative example 4
the procedure of this example is substantially the same as example 4, except that:
In step S2, the ion denitration agent is a mixed solution of sodium chlorite, sodium hypochlorite, and sodium sulfide, and the final concentration of the mixed solution is: 0.8mmol/L of sodium chlorite, 2mmol/L of sodium hypochlorite and 1.5mmol/L of sodium sulfide, and in the preparation process, a 15 wt% sodium chlorite solution is adopted as the sodium chlorite.
after 5 times of parallel tests, the average impurity removal rate of the standard-reaching flue gas is 74 percent of NOx removal rate, 90 percent of SO 2 removal rate and 94.6 percent of dust removal rate.
The ionic denitration agent has the advantages that the electromotive force formed by sodium chlorite and sodium hypochlorite is insufficient due to low proportion, the oxidizability is weakened, the denitration effect is influenced, and the overall purification efficiency is further influenced.
Example 5
The procedure of this example is substantially the same as example 3, except that:
In step S2, the ion denitration agent is a mixed solution of sodium chlorite, sodium hypochlorite, and sodium sulfide, and the final concentration of the mixed solution is: 4mmol/L of sodium chlorite, 6mmol/L of sodium hypochlorite and 3mmol/L of sodium sulfide, and in the preparation process, a 30 wt% sodium chlorite solution is adopted as the sodium chlorite.
After 5 times of parallel tests, the average impurity removal rate of the standard-reaching flue gas is 95.2 percent of NOx removal rate, 94 percent of SO 2 removal rate and 98.2 percent of dust removal rate.
comparative example 5
The procedure of this example is substantially the same as example 5, except that:
In step S2, the ion denitration agent is a mixed solution of sodium chlorite, sodium hypochlorite, and sodium sulfide, and the final concentration of the mixed solution is: 4.2mmol/L of sodium chlorite, 6mmol/L of sodium hypochlorite and 3mmol/L of sodium sulfide.
After 5 times of parallel tests, the average impurity removal rate of the standard-reaching flue gas is 70 percent of NOx removal rate, 92 percent of SO 2 removal rate and 95.2 percent of dust removal rate.
the ionic denitration agent has the advantages that the oxidation of sodium chlorite in the ionic denitration agent is weakened due to overlarge electromotive force resistance formed by sodium chlorite and the ionic denitration agent, so that the denitration effect is influenced, and the overall purification efficiency is further influenced.
Example 6
The procedure of this example is substantially the same as example 3, except that:
In step S1, the molar ratio of Ca element to S element is controlled to be 1: 1;
After 5 times of parallel tests, the average impurity removal rate of the standard-reaching flue gas is that the NOx removal rate is 96.1 percent, the SO 2 removal rate is 95.7 percent and the dust removal rate is 99.2 percent.
Comparative example 6
the procedure of this example is substantially the same as example 3, except that:
In step S1, the molar ratio of Ca element to S element is controlled to be 0.8: 1;
after 5 times of parallel tests, the average impurity removal rate of the standard-reaching flue gas is 88.2 percent of NOx removal rate, 85.6 percent of SO 2 removal rate and 96.3 percent of dust removal rate.
It is shown that if the molar ratio of Ca/S is too small in the primary desulfurization system, the absorption capacity of the slaked lime slurry to SO 2 is insufficient, SO that the desulfurization effect is influenced, and the overall purification efficiency is further influenced.
example 7
The procedure of this example is substantially the same as example 3, except that:
In step S1, the molar ratio of Ca element to S element is controlled to be 3: 1;
after 5 times of parallel tests, the average impurity removal rate of the standard-reaching flue gas is 95.3 percent of NOx removal rate, 95.9 percent of SO 2 removal rate and 99.3 percent of dust removal rate.
Comparative example 7
The procedure of this example is substantially the same as example 3, except that:
In step S1, the molar ratio of Ca element to S element is controlled to be 3.2: 1;
After 5 times of parallel tests, the average impurity removal rate of the standard-reaching flue gas is 79.7 percent of NOx removal rate, 90.6 percent of SO 2 removal rate and 92.3 percent of dust removal rate.
it is shown that if the molar ratio of Ca/S is too large in the primary desulfurization system, the slaked lime slurry is easy to agglomerate and solidify, SO that the absorption capacity of SO 2 is insufficient indirectly, the desulfurization effect is influenced, and the overall purification efficiency is influenced.
Example 8
the procedure of this example is substantially the same as example 3, except that:
step S1, the temperature of the flue gas to be processed is 160 ℃; in step S2, controlling the reaction temperature of ion denitration to be 80 ℃;
after 5 times of parallel tests, the average impurity removal rate of the standard-reaching flue gas is that the NOx removal rate is 96.5%, the SO 2 removal rate is 96.2% and the dust removal rate is 99.5%.
Example 9
The procedure of this example is substantially the same as example 3, except that:
Step S1, the temperature of the flue gas to be processed is 200 ℃; in step S2, controlling the reaction temperature of ion denitration to be 100 ℃;
after 5 times of parallel tests, the average impurity removal rate of the standard-reaching flue gas is 95.6 percent of NOx removal rate, 95.4 percent of SO 2 removal rate and 99.2 percent of dust removal rate.
it should be noted that the above embodiments can be freely combined as required, and further description is omitted here for many other combinations. The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.
Claims (10)
1. The utility model provides a semi-dry method ion denitration desulfurization dust removal integration processing apparatus which characterized in that includes:
the flue system comprises a primary desulfurization system and an ion denitration system which are sequentially arranged in a flue along the flow direction of flue gas;
The secondary desulfurization system is arranged at the downstream of the flue system; the secondary desulfurization system comprises a Venturi tube and a desulfurization tower, wherein the gas inlet section of the Venturi tube is communicated with the tail end of the flue system, and the gas outlet section of the Venturi tube is communicated with the inside of the desulfurization tower;
the dust remover is communicated with the exhaust port of the desulfurizing tower; one path of the exhaust end of the dust remover is connected with a clean flue gas exhaust pipeline, and the clean flue gas exhaust pipeline is connected into a flue system through a clean flue gas recirculation flue and an electric switch regulating valve to form a clean flue gas recirculation system; the dust collecting end of the dust remover is connected to the air inlet section of the venturi tube through a circulating ash system.
2. The processing apparatus according to claim 1, characterized in that:
The flue comprises a horizontal section and a bent section; the primary desulfurization system and the ion denitration system are sequentially arranged in the horizontal section and are connected with the Venturi tube through the bent connection section; and/or the presence of a gas in the gas,
The bottom of the flue is provided with an ash deposition bucket which is communicated with the flue, and the ash deposition bucket is respectively arranged under the air inlet section of the corresponding Venturi tube and under the primary desulfurization system and the ion denitration system.
3. the processing apparatus according to claim 2, characterized in that:
The bending section between the ion denitration system and the Venturi tube is also provided with an air flow uniform distribution device.
4. the processing apparatus according to claim 1, characterized in that:
The primary desulfurization system comprises double backflow spray guns, the spray openings of the double backflow spray guns face the flue, and/or the double backflow spray guns are used for spraying Ca (OH) 2 slurry to react with flue gas,
The ion denitration system comprises double backflow spray guns, and spray ports of the double backflow spray guns face the interior of the flue and are used for spraying ion denitration agents to react with flue gas.
5. The processing apparatus according to claim 1, characterized in that:
the venturi pipe's section of giving vent to anger is established to export and expands the pipeline section, be equipped with the water jet equipment towards the inside of desulfurizing tower in the export expands the pipeline section for reduce the interior gas temperature of desulfurizing tower.
6. A semi-dry ion denitration, desulfurization and dust removal integrated treatment process is characterized by comprising the following steps:
S1, introducing the flue gas to be treated from the flue, and preliminarily reacting most of SO 2 in the flue gas with Ca (OH) 2 solution by spraying slaked lime slurry at the first section of the inlet flue of the desulfurizing tower;
S2, spraying an ion denitration agent at the second section of the inlet flue of the desulfurization reactor to convert NO in the flue gas into NO 2;
S3, accelerating the flue gas to enter a circulating fluidized bed in a desulfurizing tower for secondary desulfurization through a venturi tube, spraying process water into the tower through a water spraying device above the venturi tube, reducing the temperature of the flue gas in the desulfurizing tower to about 75-85 ℃, converting the reaction of SO 2 and Ca (OH) 2 into an instantaneously finished ionic reaction, and humidifying and atomizing solid Ca (OH) 2 which is carried in the flue gas and has not yet reacted and solid CaO contained in solid CaSO 3 and CaSO 4;
discharging the purified dust-containing flue gas from the top of the desulfurizing tower, and then feeding the flue gas into a dust remover for gas-solid separation; the solid particles collected by the dust remover pass through a circulating ash system at the downstream of the dust remover and return to the absorption tower to continue to participate in the reaction, and the process is circulated;
And S4, discharging the treated flue gas reaching the standard.
7. The process of claim 6, wherein:
in step S2, the ion denitration agent is a mixed solution of sodium chlorite, sodium hypochlorite and sodium sulfide, and the molar ratio of the sodium chlorite to the sodium hypochlorite to the sodium sulfide is (1-4): (2-6): 1.5-3.
8. the process of claim 7, wherein:
the mole ratio of sodium chlorite to sodium hypochlorite to sodium sulfide in the ionic denitration agent is 2: 4: 2.
9. The process of claim 7, wherein:
In step S1, the molar ratio of Ca element to S element in the flue gas is controlled to be (1-3): 1;
and/or in the step S2, controlling the reaction temperature of the denitration of the reactive ions to be 50-100 ℃.
10. The process of claim 6, wherein:
in step S3, the flue gas enters the venturi tube and then enters the desulfurizing tower through the gas flow distribution device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910898291.3A CN110548387A (en) | 2019-09-23 | 2019-09-23 | integrated treatment device and process for ion denitration, desulfurization and dust removal by semidry method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910898291.3A CN110548387A (en) | 2019-09-23 | 2019-09-23 | integrated treatment device and process for ion denitration, desulfurization and dust removal by semidry method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110548387A true CN110548387A (en) | 2019-12-10 |
Family
ID=68741274
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910898291.3A Pending CN110548387A (en) | 2019-09-23 | 2019-09-23 | integrated treatment device and process for ion denitration, desulfurization and dust removal by semidry method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110548387A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113019090A (en) * | 2021-04-14 | 2021-06-25 | 吉林省铸洁环保有限责任公司 | Dust removal and desulfurization self-circulation system |
| WO2021134925A1 (en) * | 2019-12-30 | 2021-07-08 | 童裳慧 | Semi-dry flue gas desulfurization and denitrification method |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201239608Y (en) * | 2008-06-27 | 2009-05-20 | 中电投远达环保工程有限公司 | Integrated system for simultaneous desulfuration and denitration using semidry process |
| CN101983755A (en) * | 2010-11-05 | 2011-03-09 | 浙江菲达脱硫工程有限公司 | Dry-type flue gas desulphurization, denitration and dedusting integrated device and method |
| CN103566725A (en) * | 2013-10-15 | 2014-02-12 | 中国科学院过程工程研究所 | Device and method for jointly removing sulphur, saltpeter and mercury by semidry method through circulating fluidized bed |
| CN104984656A (en) * | 2015-06-23 | 2015-10-21 | 哈尔滨工业大学 | Multistage internal circulation semi-dry method desulfurization, denitrification and demercuration integrated device |
| CN108636092A (en) * | 2018-05-24 | 2018-10-12 | 南京石博环保科技有限公司 | A kind of flue gas desulfurization and denitrification system and method |
| CN109833748A (en) * | 2017-11-29 | 2019-06-04 | 中科天龙（厦门）环保股份有限公司 | A kind of near-zero release flue gas coordinated desulfurization denitration dust collecting group technology |
| CN210934428U (en) * | 2019-09-23 | 2020-07-07 | 上海蓝科石化环保科技股份有限公司 | Integrated treatment device for ion denitration, desulfurization and dust removal by semidry method |
-
2019
- 2019-09-23 CN CN201910898291.3A patent/CN110548387A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201239608Y (en) * | 2008-06-27 | 2009-05-20 | 中电投远达环保工程有限公司 | Integrated system for simultaneous desulfuration and denitration using semidry process |
| CN101983755A (en) * | 2010-11-05 | 2011-03-09 | 浙江菲达脱硫工程有限公司 | Dry-type flue gas desulphurization, denitration and dedusting integrated device and method |
| CN103566725A (en) * | 2013-10-15 | 2014-02-12 | 中国科学院过程工程研究所 | Device and method for jointly removing sulphur, saltpeter and mercury by semidry method through circulating fluidized bed |
| CN104984656A (en) * | 2015-06-23 | 2015-10-21 | 哈尔滨工业大学 | Multistage internal circulation semi-dry method desulfurization, denitrification and demercuration integrated device |
| CN109833748A (en) * | 2017-11-29 | 2019-06-04 | 中科天龙（厦门）环保股份有限公司 | A kind of near-zero release flue gas coordinated desulfurization denitration dust collecting group technology |
| CN108636092A (en) * | 2018-05-24 | 2018-10-12 | 南京石博环保科技有限公司 | A kind of flue gas desulfurization and denitrification system and method |
| CN210934428U (en) * | 2019-09-23 | 2020-07-07 | 上海蓝科石化环保科技股份有限公司 | Integrated treatment device for ion denitration, desulfurization and dust removal by semidry method |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2021134925A1 (en) * | 2019-12-30 | 2021-07-08 | 童裳慧 | Semi-dry flue gas desulfurization and denitrification method |
| CN113019090A (en) * | 2021-04-14 | 2021-06-25 | 吉林省铸洁环保有限责任公司 | Dust removal and desulfurization self-circulation system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108636098A (en) | A kind of the minimum discharge purifier and its method of burning city domestic garbage flue gas | |
| CN202185253U (en) | Exhaust gas purifying system for waste incineration | |
| CN102974181A (en) | Flue gas dedusting and desulfurization and denitrification craft and special device thereof | |
| CN102114386B (en) | Desulfurization and demercuration method for flue gas | |
| CN102233230A (en) | Waste burning smoke purification process and purification system | |
| CN101342459A (en) | Exhuast gas desulfurization, recycle and treatment method and apparatus | |
| CN112121614A (en) | Stable ultralow emission device and method for solid waste incineration flue gas | |
| CN206240299U (en) | A kind of coke oven flue waste gas purification waste heat recovery apparatus | |
| CN110548387A (en) | integrated treatment device and process for ion denitration, desulfurization and dust removal by semidry method | |
| CN111957197A (en) | Efficient flue gas deacidification, dioxin removal and waste heat utilization cooperative system and process | |
| CN116262198A (en) | Two-stage dry desulfurization deacidification dust removal process for waste incineration flue gas | |
| CN205102149U (en) | Multiple gas cleaning is demercuration device in coordination | |
| CN108561893B (en) | Industrial boiler flue gas multi-pollutant cooperative control device and process flow thereof | |
| CN106178877A (en) | A kind of coke oven flue waste gas purification waste heat recovery apparatus and technique | |
| CN112675698B (en) | Desulfurization, denitrification and dust removal device of turbulent bed in separate bin and process thereof | |
| CN210934428U (en) | Integrated treatment device for ion denitration, desulfurization and dust removal by semidry method | |
| CN105222143A (en) | Mercury removal device and method are worked in coordination with in one kind of multiple gas cleanings | |
| CN102886203B (en) | A kind of method of flue gas desulfurizing and hydrargyrum-removing | |
| CN113117480A (en) | Method for flue gas desulfurization and denitration by using calcium-based absorbent | |
| CN111085092A (en) | Desulfurization and dust removal device and desulfurization and dust removal method for gas boiler | |
| CN115990401A (en) | Purification process and device for waste incineration flue gas | |
| CN202724993U (en) | Flue gas desulphurization system combining dry process and wet process | |
| TW202010565A (en) | Aerosol generation controlling method during absorption process of ammonia desulfurization capable of realizing highly efficient desulfurization and dust removal while controlling ammonia escape and aerosol generation | |
| CN113559692A (en) | Double-tower double-circulation semi-dry desulfurization device, process and application | |
| CN209828707U (en) | Flue gas full-dry purification device |
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 |