CN117000027A - Chlorination tail gas purification and resource utilization system - Google Patents
Chlorination tail gas purification and resource utilization system Download PDFInfo
- Publication number
- CN117000027A CN117000027A CN202311144327.1A CN202311144327A CN117000027A CN 117000027 A CN117000027 A CN 117000027A CN 202311144327 A CN202311144327 A CN 202311144327A CN 117000027 A CN117000027 A CN 117000027A
- Authority
- CN
- China
- Prior art keywords
- tower
- hydrochloric acid
- acid
- sodium hypochlorite
- absorption
- 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
- 238000005660 chlorination reaction Methods 0.000 title claims abstract description 29
- 238000000746 purification Methods 0.000 title claims abstract description 18
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims abstract description 375
- 238000010521 absorption reaction Methods 0.000 claims abstract description 152
- 239000007789 gas Substances 0.000 claims abstract description 146
- SUKJFIGYRHOWBL-UHFFFAOYSA-N sodium hypochlorite Chemical group [Na+].Cl[O-] SUKJFIGYRHOWBL-UHFFFAOYSA-N 0.000 claims abstract description 87
- 238000006298 dechlorination reaction Methods 0.000 claims abstract description 78
- 239000005708 Sodium hypochlorite Substances 0.000 claims abstract description 64
- 239000000460 chlorine Substances 0.000 claims abstract description 44
- IXCSERBJSXMMFS-UHFFFAOYSA-N hydrogen chloride Substances Cl.Cl IXCSERBJSXMMFS-UHFFFAOYSA-N 0.000 claims abstract description 44
- 229910000041 hydrogen chloride Inorganic materials 0.000 claims abstract description 44
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 claims abstract description 43
- 229910052801 chlorine Inorganic materials 0.000 claims abstract description 43
- 239000003595 mist Substances 0.000 claims abstract description 17
- 238000007599 discharging Methods 0.000 claims abstract description 6
- 230000000382 dechlorinating effect Effects 0.000 claims abstract description 4
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 claims abstract description 3
- 229910052708 sodium Inorganic materials 0.000 claims abstract description 3
- 239000011734 sodium Substances 0.000 claims abstract description 3
- 239000002253 acid Substances 0.000 claims description 172
- 239000007788 liquid Substances 0.000 claims description 60
- 239000012071 phase Substances 0.000 claims description 55
- 239000007791 liquid phase Substances 0.000 claims description 24
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 17
- 238000004064 recycling Methods 0.000 claims description 15
- 238000003860 storage Methods 0.000 claims description 13
- 239000003513 alkali Substances 0.000 claims description 12
- 239000000945 filler Substances 0.000 claims description 12
- 238000012856 packing Methods 0.000 claims description 8
- 239000008235 industrial water Substances 0.000 claims description 5
- 206010015137 Eructation Diseases 0.000 claims description 3
- 238000003795 desorption Methods 0.000 claims description 2
- OYOKPDLAMOMTEE-UHFFFAOYSA-N 4-chloro-1,3-dioxolan-2-one Chemical compound ClC1COC(=O)O1 OYOKPDLAMOMTEE-UHFFFAOYSA-N 0.000 description 12
- 238000000034 method Methods 0.000 description 8
- 238000006243 chemical reaction Methods 0.000 description 7
- KZBUYRJDOAKODT-UHFFFAOYSA-N Chlorine Chemical compound ClCl KZBUYRJDOAKODT-UHFFFAOYSA-N 0.000 description 6
- 239000000047 product Substances 0.000 description 6
- SBLRHMKNNHXPHG-UHFFFAOYSA-N 4-fluoro-1,3-dioxolan-2-one Chemical compound FC1COC(=O)O1 SBLRHMKNNHXPHG-UHFFFAOYSA-N 0.000 description 5
- KMTRUDSVKNLOMY-UHFFFAOYSA-N Ethylene carbonate Chemical compound O=C1OCCO1 KMTRUDSVKNLOMY-UHFFFAOYSA-N 0.000 description 5
- 239000002994 raw material Substances 0.000 description 5
- VAYTZRYEBVHVLE-UHFFFAOYSA-N 1,3-dioxol-2-one Chemical compound O=C1OC=CO1 VAYTZRYEBVHVLE-UHFFFAOYSA-N 0.000 description 4
- 238000004519 manufacturing process Methods 0.000 description 4
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 description 3
- 229910001416 lithium ion Inorganic materials 0.000 description 3
- YBBRCQOCSYXUOC-UHFFFAOYSA-N sulfuryl dichloride Chemical compound ClS(Cl)(=O)=O YBBRCQOCSYXUOC-UHFFFAOYSA-N 0.000 description 3
- 238000005406 washing Methods 0.000 description 3
- 239000002000 Electrolyte additive Substances 0.000 description 2
- 239000000654 additive Substances 0.000 description 2
- 230000000996 additive effect Effects 0.000 description 2
- 239000006227 byproduct Substances 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- FOCAUTSVDIKZOP-UHFFFAOYSA-N chloroacetic acid Chemical compound OC(=O)CCl FOCAUTSVDIKZOP-UHFFFAOYSA-N 0.000 description 1
- 229940106681 chloroacetic acid Drugs 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- BIXZHMJUSMUDOQ-UHFFFAOYSA-N dichloran Chemical compound NC1=C(Cl)C=C([N+]([O-])=O)C=C1Cl BIXZHMJUSMUDOQ-UHFFFAOYSA-N 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000003792 electrolyte Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000012025 fluorinating agent Substances 0.000 description 1
- 229910052736 halogen Inorganic materials 0.000 description 1
- 150000002367 halogens Chemical group 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 229910052744 lithium Inorganic materials 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 150000002894 organic compounds Chemical class 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 125000000472 sulfonyl group Chemical group *S(*)(=O)=O 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- 239000002912 waste gas Substances 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
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
- B01D53/77—Liquid phase processes
- B01D53/78—Liquid phase processes with gas-liquid contact
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B7/00—Halogens; Halogen acids
- C01B7/01—Chlorine; Hydrogen chloride
- C01B7/07—Purification ; Separation
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Organic Chemistry (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)
- Inorganic Chemistry (AREA)
- Treating Waste Gases (AREA)
Abstract
The invention relates to a chlorination reaction tail gas purification and resource utilization system, which comprises a hydrochloric acid absorption unit, a hydrochloric acid dechlorination unit and a sodium hypochlorite unit, wherein the hydrochloric acid absorption unit is respectively communicated with the hydrochloric acid dechlorination unit and the sodium hypochlorite unit, and a hydrochloric acid mist demister is arranged between the hydrochloric acid absorption unit and the sodium hypochlorite unit; hydrochloric acid absorption unit: the device is used for absorbing the hydrogen chloride gas in the mixed gas containing hydrogen chloride and chlorine in the tail gas of the chlorination reaction to form hydrochloric acid, removing hydrochloric acid mist of the mixed gas and then conveying the mixed gas to a sodium hypochlorite unit; hydrochloric acid dechlorination unit: the device is used for receiving the chlorine-containing hydrochloric acid discharged from the hydrochloric acid absorption unit and dechlorinating the chlorine-containing hydrochloric acid to form qualified hydrochloric acid; sodium subunit: the device is used for absorbing the mixed gas conveyed by the hydrochloric acid absorption unit to form sodium hypochlorite solution, purifying qualified tail gas and discharging the tail gas from a chimney. The invention can realize purification and resource utilization of the tail gas of the chlorination reaction, and has the advantages of high absorption efficiency, excellent product quality, low equipment cost and the like.
Description
Technical Field
The invention belongs to the technical field of purification and resource utilization of hydrogen chloride and chlorine gas mixed gas, and particularly relates to a system for purifying and resource utilization of hydrogen chloride and chlorine gas mixed gas in chlorination reaction tail gas.
Background
With the development of lithium ion batteries, the amounts of electrolyte additives fluoroethylene carbonate (FEC) and Vinylene Carbonate (VC) are rapidly increasing. FEC has received great attention as improving the cycle life of a battery, increasing the safety of a battery, and improving the low-temperature performance of a battery. Typically FEC is produced by halogen exchange reaction of chloroethylene carbonate (CEC) with a fluorinating agent in a solvent. VC is an organic film forming additive of lithium ion batteries with the most ideal effect at present, and is obtained by dechlorination reaction with CEC as a raw material. Both lithium ion battery electrolyte additives with larger dosage are produced by taking CEC as raw materials, so that the demand of CEC is obviously increased along with the increase of the yields of FEC and VC.
CEC is an organic compound of formula C 3 H 3 ClO 3 Is used as an organic synthesis intermediate and an additive for lithium battery electrolyte. The conventional CEC production process is to carry out chlorination reaction on Ethylene Carbonate (EC) and sulfonyl chloride, wherein the sulfonyl chloride is liquid, is convenient to use, and is a relatively mild and stable reaction, so that the CEC production process is the preferred method. However, the sulfonyl method produces more acid gas and has large pollution, and the method is eliminated. The current technology adopts a chlorine method, namely, CEC is prepared by the reaction of EC and chlorine. Compared with the sulfonyl chloride method, the chlorine method has the advantages of slightly poorer reaction stability and high requirement on production equipment, but less generated waste gas and small environmental protection pressure, and accords with the development trend of the current chemical industry.
CEC reaction conditions are typically n (Cl) 2 ): n (HCl) is 1.2:1, namely chlorine is excessive, and hydrogen chloride is a byproduct of the reaction, so that the gas phase of the reaction product of the product is mainly chlorine, hydrogen chloride, trace EC and CEC. The mixed gas is mainly chlorine and hydrogen chloride, and if the mixed gas is not recycled, great raw material waste is caused, so that the CEC production cost is high. Other chlorination reactions such as chloroacetic acid, 2, 6-dichloro-4-nitroaniline, and the like also present the above-described problems. Therefore, the mixed gas is purified and recycled, which is very goodIt is necessary.
Chinese patent CN 212283461U discloses a device for treating chlorinated tail gas of ethylene carbonate. In the patent, the tail gas is mainly absorbed and adsorbed through a tail gas trapping tower and a tail gas re-absorbing tower, baffle plates are arranged in the trapping tower in a relatively stepped manner and used for countercurrent absorption of hydrogen chloride, but the absorption efficiency of the structure is low, meanwhile, the removal of impurity free chlorine in hydrochloric acid is not considered, and the problems of low quality and poor stability of hydrochloric acid exist.
Disclosure of Invention
The invention aims to provide a method for purifying and recycling a mixed gas containing hydrogen chloride and chlorine in chlorination reaction tail gas, so as to solve the problems of low absorption efficiency of the hydrogen chloride, low quality of hydrochloric acid and the like in the prior art that the chlorine is not recycled.
In order to solve the technical problems, the technical scheme provided by the invention is as follows:
the system comprises a hydrochloric acid absorption unit, a hydrochloric acid dechlorination unit and a sodium hypochlorite unit, wherein the hydrochloric acid absorption unit is respectively communicated with the hydrochloric acid dechlorination unit and the sodium hypochlorite unit, and a hydrochloric acid mist demister is arranged between the hydrochloric acid absorption unit and the sodium hypochlorite unit;
hydrochloric acid absorption unit: the device is used for absorbing the hydrogen chloride gas in the mixed gas containing hydrogen chloride and chlorine in the tail gas of the chlorination reaction to form hydrochloric acid, removing hydrochloric acid mist of the mixed gas and then conveying the mixed gas to a sodium hypochlorite unit;
hydrochloric acid dechlorination unit: the device is used for receiving the chlorine-containing hydrochloric acid discharged from the hydrochloric acid absorption unit and dechlorinating the chlorine-containing hydrochloric acid to form qualified hydrochloric acid;
sodium subunit: the device is used for absorbing the mixed gas conveyed by the hydrochloric acid absorption unit to form sodium hypochlorite solution, purifying qualified tail gas and discharging the tail gas from a chimney.
The system can absorb the hydrogen chloride and the chlorine in the tail gas into hydrochloric acid and sodium hypochlorite respectively.
Preferably, the hydrochloric acid absorption unit comprises a hydrochloric acid combined absorption tower, a dilute acid circulation tank, a concentrated acid cooler, a dilute acid cooler, a concentrated acid circulation pump and a dilute acid circulation pump, wherein the concentrated acid absorption section, the dilute acid storage section, the dilute acid absorption section and the clear water absorption section are sequentially arranged in the hydrochloric acid combined absorption tower from bottom to top, the concentrated acid absorption section is communicated with the concentrated acid cooler, the dilute acid storage section is communicated with the dilute acid circulation tank, the dilute acid absorption section is communicated with the dilute acid cooler, the concentrated acid cooler is communicated with the hydrochloric acid combined absorption tower through the concentrated acid circulation pump, and the dilute acid circulation tank is communicated with the dilute acid cooler through the dilute acid circulation pump.
The hydrochloric acid combined absorption tower is used for washing and absorbing hydrogen chloride gas generated by the chlorination reaction to form finished hydrochloric acid, and conveying unabsorbed chlorine gas to the sodium hypochlorite unit;
the dilute acid circulating tank is used for collecting dilute hydrochloric acid generated by the dilute acid absorption section and overflows to the tower bottom of the hydrochloric acid combined absorption tower;
the hydrochloric acid mist demister is used for removing hydrochloric acid mist drops in the hydrogen chloride and chlorine gas mixed gas;
the concentrated acid cooler and the dilute acid cooler are respectively used for removing the absorption heat of the concentrated acid section and the absorption heat of the dilute acid section;
the concentrated acid circulating pump, the dilute acid circulating pump and the dechlorination tower circulating pump are respectively used for conveying hydrochloric acid with various concentrations;
the concentrated acid absorption section is used for recycling the concentrated acid in the concentrated acid absorption section, countercurrent absorbing the hydrogen chloride gas to form concentrated acid with higher concentration, and conveying the unabsorbed hydrogen chloride gas to the dilute acid absorption section;
the dilute acid absorption section is used for recycling dilute acid in the dilute acid absorption section, absorbing hydrogen chloride gas in a countercurrent way to form dilute acid with larger concentration, and conveying the hydrogen chloride gas which is not absorbed yet to the clear water absorption section;
the clean water absorption section is used for absorbing the hydrogen chloride gas through industrial water to form low-concentration dilute acid and conveying the mixed gas of the hydrogen chloride and the chlorine which are not absorbed yet to the sodium hypochlorite unit.
Preferably, the hydrochloric acid dechlorination unit comprises a hydrochloric acid dechlorination tower, a dechlorination tower fan and a dechlorination tower circulating pump, a dechlorination tower gas phase inlet and a dechlorination tower liquid phase inlet are arranged at the lower part of the hydrochloric acid dechlorination tower, a dechlorination tower liquid distributor is arranged at the upper part of the hydrochloric acid dechlorination tower, a hydrochloric acid outlet is arranged at the bottom of the hydrochloric acid dechlorination tower, a dechlorination tower gas phase outlet is arranged at the top of the hydrochloric acid dechlorination tower, the dechlorination tower gas phase inlet is communicated with the dechlorination tower fan, the dechlorination tower gas phase outlet is communicated with a hydrochloric acid combined absorption tower inlet, the dechlorination tower liquid phase inlet is communicated with a concentrated acid circulating pump, the hydrochloric acid outlet is communicated with the dechlorination tower liquid distributor through a pipeline, and the dechlorination tower circulating pump is arranged on the pipeline connecting the hydrochloric acid outlet and the dechlorination tower liquid distributor.
The hydrochloric acid dechlorination tower is contacted with chlorine-containing hydrochloric acid through air countercurrent to desorb chlorine from the chlorine-containing hydrochloric acid to form high-quality hydrochloric acid;
the dechlorination tower fan is used for conveying air required by the hydrochloric acid dechlorination tower.
Preferably, the sodium hypochlorite unit comprises a sodium hypochlorite tower, a security tower, a tail gas fan and a chimney which are sequentially communicated; the sodium hypochlorite tower is provided with a sodium hypochlorite tower gas phase inlet, a sodium hypochlorite tower gas phase outlet and a sodium hypochlorite tower liquid phase outlet, the sodium hypochlorite tower gas phase inlet is communicated with a hydrochloric acid mist demister gas phase outlet, the sodium hypochlorite tower liquid phase outlet is communicated with a sodium hypochlorite tower liquid distributor through a pipeline, and a sodium hypochlorite circulating pump and a sodium hypochlorite cooler are arranged on the pipeline connecting the sodium hypochlorite tower liquid phase outlet and the sodium hypochlorite tower liquid distributor;
the safety tower is provided with a safety tower gas phase inlet, a safety tower gas phase outlet and a safety tower liquid phase outlet, wherein the safety tower gas phase inlet is communicated with the sodium hypochlorite tower gas phase outlet, the safety tower liquid phase outlet is communicated with the safety tower liquid distributor through a pipeline, and an alkali liquor circulating pump and an alkali liquor cooler are arranged on the pipeline connecting the safety tower liquid phase outlet and the safety tower liquid distributor.
The sodium hypochlorite tower is used for washing and absorbing the chlorine gas conveyed by the hydrochloric acid absorption unit to form finished sodium hypochlorite, and conveying the unabsorbed chlorine gas to the security tower;
the safety tower is used for washing and absorbing trace chlorine at the outlet of the sodium hypochlorite tower, so that the discharged tail gas meets the discharge standard;
a sodium hypochlorite cooler and an alkali liquor cooler for removing the reaction heat of sodium hypochlorite;
the sodium hypochlorite circulating pump and the alkali liquor circulating pump are respectively used for conveying sodium hypochlorite and alkali liquor;
and the tail gas blower and the chimney are used for discharging the tail gas reaching the standard through the chimney at high altitude.
Preferably, the lower part of the hydrochloric acid combined absorption tower is provided with a hydrochloric acid combined absorption tower inlet, the bottom of the hydrochloric acid combined absorption tower is provided with a concentrated acid outlet, a first liquid distributor is arranged above the concentrated acid absorption section, the concentrated acid outlet is communicated with the first liquid distributor through a pipeline, and a concentrated acid circulating pump and a concentrated acid cooler are arranged on the pipeline connecting the concentrated acid outlet and the first liquid distributor.
Preferably, a gas raising pipe is arranged in the dilute acid liquid storage section, the dilute acid liquid storage section is connected with a dilute acid circulating tank, a second liquid distributor is arranged above the dilute acid absorption section, the dilute acid circulating tank is communicated with the second liquid distributor through a pipeline, and a dilute acid circulating pump and a dilute acid cooler are arranged on the pipeline connecting the dilute acid circulating tank and the second liquid distributor; the dilute acid circulating tank is connected to the tower bottom of the concentrated acid absorption section in the hydrochloric acid combined absorption tower through a pipeline.
Preferably, a third liquid distributor for introducing industrial water is arranged above the clean water absorption section.
Preferably, the hydrochloric acid mist demister is provided with a demister gas phase inlet, a demister gas phase outlet and an overflow port, wherein the demister gas phase inlet is communicated with a hydrochloric acid combined absorption tower gas phase outlet, the demister gas phase outlet is communicated with a sodium hypochlorite tower gas phase inlet, and the overflow port is communicated with a tower kettle of a concentrated acid absorption section in the hydrochloric acid combined absorption tower and is used for discharging hydrochloric acid trapped by the demister.
Preferably, the hydrochloric acid combined absorption tower is a filler combined tower, the hydrochloric acid dechlorination tower is a filler desorption tower, and the sodium hypochlorite tower is a filler absorption tower.
Preferably, the absorption forms of the concentrated acid absorption section, the dilute acid absorption section and the clear water absorption section are all filler absorption, and the filler is random packing or structured packing.
Compared with the prior art, the technical scheme provided by the invention has the following beneficial effects:
1. the system can realize the integrated purification of the hydrogen chloride which is a byproduct of the chlorination reaction and the excessive chlorine mixed gas in the raw materials, and can form high-quality hydrochloric acid and sodium hypochlorite products;
2. the hydrochloric acid combined absorption tower is in a three-in-one combination (a concentrated acid absorption section, a dilute acid absorption section and a clear water absorption section), three concentration gradients are formed through one tower to carry out multistage absorption on the hydrogen chloride, and the absorption efficiency is high;
3. the product concentration, the raw material flow and the like in the system can be monitored by adopting an online instrument, so that automatic control can be realized, the operation efficiency is effectively improved, and the labor cost is reduced;
4. the system has the advantages of low cost, high absorption efficiency, high product quality, low equipment cost, and good economic and environmental protection benefits, and the tail gas emission and the product quality of the system meet the national standard, the hydrochloric acid concentration is more than or equal to 31%, the free chlorine is less than or equal to 25ppm, and the sodium hypochlorite concentration is more than or equal to 10.5%.
Drawings
FIG. 1 is a schematic flow diagram of a chlorination tail gas purification and resource utilization system;
fig. 2 is a schematic structural diagram of a hydrochloric acid combined absorption tower.
Detailed Description
The invention will be further understood by reference to the following examples which are given to illustrate the invention but are not intended to limit the scope of the invention.
Referring to fig. 1 and 2, a system for purifying tail gas of chlorination reaction and recycling comprises a hydrochloric acid unit, a hydrochloric acid dechlorination unit and a sodium hypochlorite unit, wherein the hydrochloric acid absorption unit is respectively communicated with the hydrochloric acid dechlorination unit and the sodium hypochlorite unit, and a hydrochloric acid mist demister 3 is arranged between the hydrochloric acid absorption unit and the sodium hypochlorite unit.
The hydrochloric acid absorption unit is used for absorbing the hydrogen chloride gas in the mixed gas containing hydrogen chloride and chlorine in the tail gas of the chlorination reaction and conveying the mixed gas of hydrogen chloride and chlorine which is not completely absorbed to the sodium hypochlorite unit; the hydrochloric acid dechlorination unit is used for dechlorinating the chloric hydrochloric acid absorbed by the hydrochloric acid absorption unit to form qualified hydrochloric acid. The hydrochloric acid absorption unit comprises a hydrochloric acid combined absorption tower 1, a concentrated acid circulating pump 11, a dilute acid circulating pump 12, a concentrated acid cooler 13, a dilute acid circulating tank 14 and a dilute acid cooler 15, and the hydrochloric acid dechlorination unit comprises a hydrochloric acid dechlorination tower 2, a dechlorination tower circulating pump 21 and a dechlorination tower fan 22.
The hydrochloric acid combined absorption tower 1 is internally provided with a concentrated acid absorption section 16, a dilute acid absorption section 17 and a clear water absorption section 18 from bottom to top in sequence.
The concentrated acid absorption section 16 is used for recycling concentrated acid in the concentrated acid absorption section, the hydrogen chloride gas is absorbed in a countercurrent way to form concentrated acid with larger concentration, the unabsorbed hydrogen chloride gas is conveyed to the dilute acid absorption section 17, the lower part of the hydrochloric acid combined absorption tower is provided with a hydrochloric acid combined absorption tower inlet 1-1, the bottom of the hydrochloric acid combined absorption tower is provided with a concentrated acid outlet 1-2, a first liquid distributor 1-3 is arranged above the concentrated acid absorption section 16, the hydrochloric acid combined absorption tower inlet 1-1 is communicated with a chlorination reaction working section, the concentrated acid outlet 1-2 is communicated with the first liquid distributor 1-3 through a pipeline, and a concentrated acid circulating pump 11 and a concentrated acid cooler 13 are arranged on the pipeline which is connected with the concentrated acid outlet 1-2 and the first liquid distributor 1-3;
the dilute acid absorption section 17 is used for recycling dilute acid in the dilute acid absorption section, absorbing hydrogen chloride gas in a countercurrent manner to form dilute acid with larger concentration, and conveying the hydrogen chloride gas which is not absorbed yet to the clear water absorption section 18; a dilute acid liquid storage section 19 is arranged below the dilute acid absorption section 17, a gas raising pipe 1-4 is arranged in the dilute acid liquid storage section 19, the dilute acid liquid storage section 19 is communicated with a dilute acid circulation tank 14 through a pipeline, a second liquid distributor 1-5 is arranged above the dilute acid absorption section 19, the dilute acid circulation tank 14 is communicated with the second liquid distributor 1-5 through a pipeline, and a dilute acid circulation pump 12 and a dilute acid cooler 15 are arranged on the pipeline connecting the dilute acid circulation tank 14 and the second liquid distributor 1-5; the dilute acid circulation tank 14 is also connected to the concentrated acid absorption Duan Dafu of the hydrochloric acid combined absorption tower 1 through a pipeline, so that the dilute acid can be introduced into the concentrated acid absorption section 16, and the hydrogen chloride gas in the concentrated acid absorption section 16 is absorbed to form the concentrated acid, so that the yield of the concentrated acid can be improved.
The clean water absorption section 18 is used for absorbing the hydrogen chloride gas through industrial water to form low-concentration dilute acid and conveying the mixed gas of the hydrogen chloride and the chlorine which are not absorbed yet to the sodium hypochlorite unit; a liquid distributor for introducing industrial water is arranged above the clean water absorption section 18.
The hydrochloric acid combined absorption tower is characterized in that low-concentration dilute acid formed by a clear water absorption section 18 sequentially enters a dilute acid absorption section 17 from the inside of the tower and continuously absorbs hydrogen chloride gas to form high-concentration dilute acid, the high-concentration dilute acid is stored in a dilute acid storage section 19, when the dilute acid storage section 19 stores a certain amount, the dilute acid is introduced into a dilute acid circulation tank 14, a dilute acid part in the dilute acid circulation tank 14 is circularly conveyed to the dilute acid absorption section through a dilute acid circulation pump 12 and continuously absorbs the hydrogen chloride gas, so that the concentration of the dilute acid in the dilute acid circulation tank 14 is continuously increased, when the liquid level of the dilute acid circulation tank 14 is increased to a certain height, the high-concentration dilute acid in the dilute acid circulation tank 14 is introduced into a concentrated acid absorption section 16 and absorbs the hydrogen chloride gas in a hydrogen chloride gas mixture from outside a boundary to form high-quality concentrated acid, and part of the dilute acid is conveyed to a first liquid distributor of the concentrated acid circulation tank 11; part of the concentrated acid is continuously conveyed to the tower kettle of the hydrochloric acid dechlorination tower 2 through a concentrated acid circulating pump 11.
The hydrochloric acid combined absorption tower liquid distributor is a weir groove type liquid distributor, a groove disc type liquid distributor or a tubular liquid distributor.
The absorption forms of the concentrated acid absorption section 16, the dilute acid absorption section 17 and the clear water absorption section 18 are all filler absorption, and the filler is random packing or structured packing.
The hydrochloric acid dechlorination tower 2 is used for receiving the chlorine-containing concentrated acid from the hydrochloric acid combined absorption tower, and desorbing chlorine from the chlorine-containing hydrochloric acid through the contact of air countercurrent and the chlorine-containing hydrochloric acid to form high-quality hydrochloric acid; the lower part of the hydrochloric acid dechlorination tower 2 is provided with a dechlorination tower gas phase inlet 2-1 and a dechlorination tower liquid phase inlet 2-2, the bottom is provided with a hydrochloric acid outlet 2-3, the top is provided with a dechlorination tower gas phase outlet 2-4, the upper part of the tower is provided with a dechlorination tower liquid distributor 2-5, the dechlorination tower gas phase inlet 2-1 is communicated with a dechlorination tower fan 22, the dechlorination tower gas phase outlet 2-4 is communicated with an inlet of the hydrochloric acid combined absorption tower 1, the dechlorination tower liquid phase inlet 2-2 is communicated with an outlet of a concentrated acid circulating pump 11, the hydrochloric acid outlet 2-3 is communicated with the dechlorination tower liquid distributor 2-5 through a pipeline, and a dechlorination tower circulating pump 21 is arranged on the pipeline connecting the hydrochloric acid outlet 2-3 and the dechlorination tower liquid distributor 2-5.
The packing of the hydrochloric acid dechlorination tower is structured packing, and the liquid distributor is a weir groove type liquid distributor, a groove disc type liquid distributor or a tubular liquid distributor.
The hydrochloric acid mist demister 3 is provided with a demister gas phase inlet 3-1, a demister gas phase outlet 3-2 and an overflow port 3-3, wherein the demister gas phase inlet 3-1 is communicated with a gas phase outlet of the hydrochloric acid combined absorption tower 1, the demister gas phase outlet 3-2 is communicated with a gas phase inlet of the sodium-secondary unit sodium-secondary tower 4, and the overflow port 3-3 is communicated with a tower kettle of the hydrochloric acid combined absorption tower 1 and is used for discharging hydrochloric acid complemented by the demister.
The sodium hypochlorite unit is used for absorbing a small amount of mixed gas of hydrogen chloride and chlorine which is not absorbed by the hydrochloric acid unit to form sodium hypochlorite solution with a certain concentration, and achieving the standard of tail gas and high-altitude emission; the sodium hypochlorite unit comprises a sodium hypochlorite tower 4, a sodium hypochlorite circulating pump 41, a sodium hypochlorite cooler 42, a security tower 5, an alkali liquor circulating pump 51, an alkali liquor cooler 52, a tail gas fan 6 and a chimney 7.
The sodium hypochlorite tower is provided with a sodium hypochlorite tower gas phase inlet 4-1, a sodium hypochlorite tower gas phase outlet 4-2 and a sodium hypochlorite tower liquid phase outlet 4-3, wherein the sodium hypochlorite tower gas phase inlet 4-1 is communicated with the hydrochloric acid mist demister 3 gas phase outlet 3-2, the sodium hypochlorite tower liquid phase outlet 4-3 is communicated with the sodium hypochlorite tower liquid distributor 4-4 through a pipeline, and a sodium hypochlorite circulating pump 41 and a sodium hypochlorite cooler 42 are arranged on the pipeline connecting the sodium hypochlorite tower liquid phase outlet 4-3 and the sodium hypochlorite tower liquid distributor 4-4.
The safety tower is provided with a safety tower gas phase inlet 5-1, a safety tower gas phase outlet 5-2 and a safety tower liquid phase outlet 5-3, wherein the safety tower gas phase inlet 5-1 is communicated with a sodium hypochlorite tower gas phase outlet 4-2, the safety tower liquid phase outlet 5-3 is communicated with a safety tower liquid distributor 5-4 through a pipeline, and an alkali liquor circulating pump 51 and an alkali liquor cooler 52 are arranged on the pipeline connecting the safety tower liquid phase outlet 5-3 and the safety tower liquid distributor 5-4; meanwhile, a defogging cleaning device 5-5 is arranged at the top of the security tower 5.
The chlorination reaction tail gas purification and resource utilization system comprises the following specific steps:
1) Chilled water with the pressure range of 0.3-0.5 MPa and the temperature range of 5-7 ℃ is introduced into the concentrated acid cooler 13, the dilute acid cooler 15, the sodium hypochlorite cooler 42 and the alkali liquor cooler 52.
2) The mixed gas containing hydrogen chloride and chlorine from the chlorination reactor enters the hydrochloric acid combined absorption tower 1, the hydrogen chloride is subjected to countercurrent gradual absorption through a plurality of gradients such as concentrated acid absorption, dilute acid absorption, clear water absorption and the like in sequence to form chlorine-containing hydrochloric acid, and absorption heat is removed by the concentrated acid cooler 13 and the dilute acid cooler 15 respectively. The chlorine-containing hydrochloric acid is dechlorinated through a hydrochloric acid dechlorination tower 2 by an air stripping process to obtain the finished hydrochloric acid, wherein the mass concentration is more than or equal to 31% and the free chlorine is less than or equal to 25ppm.
3) A small amount of unabsorbed hydrogen chloride and chlorine at the outlet of the hydrochloric acid combined absorption tower 1 is removed by a hydrochloric acid mist catcher 3, the hydrochloric acid mist enters a sodium hypochlorite tower 4, the chlorine is circularly absorbed to generate sodium hypochlorite, and after the trace chlorine is removed by a security tower 5, the tail gas qualified in treatment is sucked to a chimney 7 by a tail gas fan 6 for high-altitude emission.
4) The three modules for producing sodium hypochlorite by hydrochloric acid absorption, hydrochloric acid dechlorination and chlorine absorption can be used independently or in combination.
The system has the advantages that the tail gas emission and the product quality meet the national standard, the hydrochloric acid concentration is more than or equal to 31%, the free chlorine is less than or equal to 25ppm, and the sodium hypochlorite concentration is more than or equal to 10.5%.
The present invention has been described in detail with reference to the embodiments, but the description is only the preferred embodiments of the present invention and should not be construed as limiting the scope of the invention. All equivalent changes and modifications within the scope of the present invention should be considered as falling within the scope of the present invention.
Claims (10)
1. A chlorination reaction tail gas purification and resource utilization system is characterized in that: the system comprises a hydrochloric acid absorption unit, a hydrochloric acid dechlorination unit and a sodium hypochlorite unit, wherein the hydrochloric acid absorption unit is respectively communicated with the hydrochloric acid dechlorination unit and the sodium hypochlorite unit, and a hydrochloric acid mist demister is arranged between the hydrochloric acid absorption unit and the sodium hypochlorite unit;
hydrochloric acid absorption unit: the device is used for absorbing the hydrogen chloride gas in the mixed gas containing hydrogen chloride and chlorine in the tail gas of the chlorination reaction to form hydrochloric acid, removing hydrochloric acid mist of the mixed gas and then conveying the mixed gas to a sodium hypochlorite unit;
hydrochloric acid dechlorination unit: the device is used for receiving the chlorine-containing hydrochloric acid discharged from the hydrochloric acid absorption unit and dechlorinating the chlorine-containing hydrochloric acid to form qualified hydrochloric acid;
sodium subunit: the device is used for absorbing the mixed gas conveyed by the hydrochloric acid absorption unit to form sodium hypochlorite solution, purifying qualified tail gas and discharging the tail gas from a chimney.
2. The chlorination tail gas purification and recycling system according to claim 1, wherein: the hydrochloric acid absorption unit comprises a hydrochloric acid combined absorption tower, a dilute acid circulation tank, a concentrated acid cooler, a dilute acid cooler, a concentrated acid circulation pump and a dilute acid circulation pump, wherein the concentrated acid absorption section, the dilute acid storage section, the dilute acid absorption section and the clear water absorption section are sequentially arranged in the hydrochloric acid combined absorption tower from bottom to top, the concentrated acid absorption section is communicated with the concentrated acid cooler, the dilute acid storage section is communicated with the dilute acid circulation tank, the dilute acid absorption section is communicated with the dilute acid cooler, the concentrated acid cooler is communicated with the hydrochloric acid combined absorption tower through the concentrated acid circulation pump, and the dilute acid circulation tank is communicated with the dilute acid cooler through the dilute acid circulation pump.
3. The chlorination tail gas purification and recycling system according to claim 2, wherein: the hydrochloric acid dechlorination unit comprises a hydrochloric acid dechlorination tower, a dechlorination tower fan and a dechlorination tower circulating pump, a dechlorination tower gas phase inlet and a dechlorination tower liquid phase inlet are formed in the lower portion of the hydrochloric acid dechlorination tower, a dechlorination tower liquid distributor is arranged on the upper portion of the hydrochloric acid dechlorination tower, a hydrochloric acid outlet is formed in the bottom of the hydrochloric acid dechlorination tower, a dechlorination tower gas phase outlet is formed in the top of the hydrochloric acid dechlorination tower, the dechlorination tower gas phase inlet is communicated with the dechlorination tower fan, the dechlorination tower gas phase outlet is communicated with the hydrochloric acid combined absorption tower inlet, the dechlorination tower liquid phase inlet is communicated with a concentrated acid circulating pump, the hydrochloric acid outlet is communicated with the dechlorination tower liquid distributor through a pipeline, and the dechlorination tower circulating pump is arranged on a pipeline connecting the hydrochloric acid outlet and the dechlorination tower liquid distributor.
4. The chlorination tail gas purification and recycling system according to claim 3, wherein:
the sodium hypochlorite unit comprises a sodium hypochlorite tower, a security tower, a tail gas fan and a chimney which are sequentially communicated;
the sodium hypochlorite tower is provided with a sodium hypochlorite tower gas phase inlet, a sodium hypochlorite tower gas phase outlet and a sodium hypochlorite tower liquid phase outlet, the sodium hypochlorite tower gas phase inlet is communicated with a hydrochloric acid mist demister gas phase outlet, the sodium hypochlorite tower liquid phase outlet is communicated with a sodium hypochlorite tower liquid distributor through a pipeline, and a sodium hypochlorite circulating pump and a sodium hypochlorite cooler are arranged on the pipeline connecting the sodium hypochlorite tower liquid phase outlet and the sodium hypochlorite tower liquid distributor;
the safety tower is provided with a safety tower gas phase inlet, a safety tower gas phase outlet and a safety tower liquid phase outlet, wherein the safety tower gas phase inlet is communicated with the sodium hypochlorite tower gas phase outlet, the safety tower liquid phase outlet is communicated with the safety tower liquid distributor through a pipeline, and an alkali liquor circulating pump and an alkali liquor cooler are arranged on the pipeline connecting the safety tower liquid phase outlet and the safety tower liquid distributor.
5. The chlorination tail gas purification and recycling system according to claim 2, wherein: the lower part of the hydrochloric acid combined absorption tower is provided with a hydrochloric acid combined absorption tower inlet, the bottom of the hydrochloric acid combined absorption tower is provided with a concentrated acid outlet, a first liquid distributor is arranged above the concentrated acid absorption section, the concentrated acid outlet is communicated with the first liquid distributor through a pipeline, and a concentrated acid circulating pump and a concentrated acid cooler are arranged on the pipeline connecting the concentrated acid outlet and the first liquid distributor.
6. The chlorination tail gas purification and recycling system according to claim 5, wherein: a gas raising pipe is arranged in the dilute acid liquid storage section, the dilute acid liquid storage section is connected with a dilute acid circulating tank, a second liquid distributor is arranged above the dilute acid absorption section, the dilute acid circulating tank is communicated with the second liquid distributor through a pipeline, and a dilute acid circulating pump and a dilute acid cooler are arranged on the pipeline connecting the dilute acid circulating tank and the second liquid distributor; the dilute acid circulating tank is connected to the tower bottom of the concentrated acid absorption section in the hydrochloric acid combined absorption tower through a pipeline.
7. The chlorination tail gas purification and recycling system according to claim 6, wherein: a third liquid distributor for introducing industrial water is arranged above the clean water absorption section.
8. The chlorination tail gas purification and recycling system according to claim 6, wherein: the hydrochloric acid mist demister is provided with a demister gas phase inlet, a demister gas phase outlet and an overflow port, wherein the demister gas phase inlet is communicated with the gas phase outlet of the hydrochloric acid combined absorption tower, the demister gas phase outlet is communicated with the gas phase inlet of the sodium hypochlorite tower, and the overflow port is communicated with the tower bottom of the concentrated acid absorption section in the hydrochloric acid combined absorption tower.
9. The chlorination tail gas purification and recycling system according to claim 4, wherein: the hydrochloric acid combined absorption tower is a filler combined tower, the hydrochloric acid dechlorination tower is a filler desorption tower, and the sodium hypochlorite tower is a filler absorption tower.
10. The chlorination tail gas purification and recycling system according to claim 2, wherein: the absorption forms of the concentrated acid absorption section, the dilute acid absorption section and the clear water absorption section are filler absorption, and the filler is random packing or structured packing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311144327.1A CN117000027A (en) | 2023-09-06 | 2023-09-06 | Chlorination tail gas purification and resource utilization system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311144327.1A CN117000027A (en) | 2023-09-06 | 2023-09-06 | Chlorination tail gas purification and resource utilization system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117000027A true CN117000027A (en) | 2023-11-07 |
Family
ID=88565658
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311144327.1A Pending CN117000027A (en) | 2023-09-06 | 2023-09-06 | Chlorination tail gas purification and resource utilization system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117000027A (en) |
-
2023
- 2023-09-06 CN CN202311144327.1A patent/CN117000027A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101235160B (en) | Hydrogen chloride whole reclaiming zero discharging technique and device for PVC producing process | |
| CN108159842B (en) | Method for reducing VOC content in tail gas generated by methane chloride device | |
| CN111330412B (en) | System and process for absorbing and purifying byproduct hydrogen chloride gas in chlorination section into acid | |
| CN101274195B (en) | Method for removing residual chlorine gas in tail gas in production processes of chloroacetic acid | |
| CN105036141A (en) | Method for producing nanosilicon dioxide and by-product hydrochloric acid through chlorosilane waste gas | |
| CN217499114U (en) | Fluoroethylene carbonate production system | |
| CN213433774U (en) | Organic tail gas purification system | |
| CN108641023B (en) | Mercury-free polyvinyl chloride production process | |
| CN220715413U (en) | Chlorination tail gas purification and resource utilization system | |
| CN109232171B (en) | Method for completely removing acidic substances in crude vinyl chloride gas | |
| CN111701404B (en) | Hydrogen chloride absorption treatment method, device and application | |
| CN117000027A (en) | Chlorination tail gas purification and resource utilization system | |
| CN116354349A (en) | Dechlorination method and system for producing hydrogen fluoride by fluosilicic acid | |
| CN214634110U (en) | Hydrochloric acid desorption device using sulfuric acid as extractant | |
| CN213101516U (en) | Hydrogen chloride absorbs processing apparatus | |
| CN211799976U (en) | Hydrogen chloride synthesis tail gas purification resource recycling device | |
| CN218307192U (en) | Tail gas treatment system of chlorinated ethylene carbonate preparation technology | |
| CN102188966A (en) | Process for recovering mercury chloride in hydrochloric-acid-containing wastewater discharged in acetylene method based poly(vinyl chloride) production and circularly producing mercury chloride catalyst | |
| CN108033433B (en) | Industrial waste acid treatment system | |
| CN216223692U (en) | Chloroethylene purification device | |
| CN111320141A (en) | Production process for synthesizing high-purity chlorosulfonic acid by gas phase circulation method | |
| CN106698368A (en) | Nitric oxide wet oxidation process | |
| CN221601658U (en) | Tail gas absorbing device | |
| CN111039745A (en) | System and method for reducing waste alkali in methane chloride production process | |
| CN214114927U (en) | Device for producing electronic-grade ammonia water by using purge gas of synthetic ammonia |
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 |