CN102728182B - Treatment method of arsenic-containing tail gas - Google Patents
Treatment method of arsenic-containing tail gas Download PDFInfo
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- CN102728182B CN102728182B CN201210244219.7A CN201210244219A CN102728182B CN 102728182 B CN102728182 B CN 102728182B CN 201210244219 A CN201210244219 A CN 201210244219A CN 102728182 B CN102728182 B CN 102728182B
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
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Abstract
The invention provides a treatment method of arsenic-containing tail gas, which is characterized by comprising the following four steps of: step 1, entering the arsenic-containing tail gas to a spray tower, carrying out reverse spray treatment using potassium permanganate solution, and discharging the treated tail gas which reaches the national standard; step 2, discharging the solution in a kettle of the spray tower in a quantitative way at the fixed time; step 3, collecting the discharged solution into a flocculent tank in a unified way for treatment; and step 4, continuously filtering and circulating the solution in the flocculent tank, filtering out solid filter residue, and discharging the wastewater which reaches the standard. The treatment method of the arsenic-containing tail gas is high in treatment efficiency, simple and convenient in operation of treatment working procedures and low in needed cost, and can be used for further treating the arsenic-containing tail gas solution so as to lead the solution to reach the discharge standard.
Description
Technical field
The present invention relates to a kind of arsenic exhaust gas treating method that contains, belong to the technical field of waste gas treatment containing Arsenic and species of Arsenic.
Background technology
Arsine is the necessary important raw and processed materials of China's space industry GaAs (GaAs) solar cell, is also the indispensable important materials of LED lighting industry (LED) fast development.
Make GaAs by arsine, mainly realize by MOCVD (metallo-organic compound chemical gaseous phase deposition).MOCVD is a kind of Novel air phase epitaxy growing technology growing up on the basis of vapor phase epitaxial growth (VPE), is that current growing semiconductor material is especially manufactured the requisite a kind of technology of opto-electronic device.
MOCVD is using the hydride of the organic compound of III family, II family element and V, VI family element etc. as crystal growth raw material, in pyrolysis mode at the enterprising promoting the circulation of qi phase epitaxy of substrate, the thin layer monocrystal material of grow various III-V family, II-VI compound semiconductor and their multivariate solid solution.Conventionally the crystal growth in MOCVD system is all at normal pressure or the lower logical H of low pressure (10～100Torr)
2cold wall quartz (or stainless steel) reative cell in carry out, underlayer temperature is 500～1200 ℃, heats graphite base (substrate base is above graphite base), H with radio frequency induction
2the fluid supply bubbling controlled by temperature carries metallorganic to vitellarium.
The basic growth equation formula of typical As reddish yellow photosemiconductor is as follows:
Ga(CH
3)
3+AsH3＝GaAs+3CH
4
Because the MO source that MOCVD growth is used is material inflammable, explosive, that toxicity is very large, and the multicomponent of will growing, large area, thin layer and superthin layer dissimilar materials.Therefore in the time of reaction, arsine must excessively can fully react with assurance MO source.Therefore in tail gas, also have arsine gas, can not directly be discharged in atmosphere, must first process it.Because arsine has severe toxicity, when emission treatment, usually with nitrogen, it is diluted, be generally diluted to arsine concentration in 1ppm left and right.
The method of processing the waste gas that contains Arsenic and species of Arsenic mainly contains three kinds: absorption method, Bubbling method and spray process.Absorption method is the processing method of utilizing the active carbon that is soaked with some oxides to adsorb arsine, and the treatment effeciency of this method is not high, and result can not guarantee, and the adsorbent that absorption arsine is used is also difficult to process; Bubbling method be by waste gas by below the liquid level of Treatment Solution, under the effect of exhaust gas pressure, the processed liquid of arsine absorbs, other gases overflow from treatment fluid, this method does not exist treatment effeciency high and can not guarantee to process rear tail gas problem up to standard equally; Spray process refers to gas motion from bottom to top in spray equipment, and treatment fluid sprays with gas haptoreaction from top to bottom, and to reach the object of processing arsine, treatment fluid used generally is oxidant.But select its treatment effeciency of different oxidants also to have a great difference, current disposal methods efficiency is not high, and the arsenic-containing waste water absorbing after arsine is not processed well.
Summary of the invention
The technical problem to be solved in the present invention be to provide a kind for the treatment of effeciency high, process after tail gas can directly discharge and to being further processed the integrated approach to qualified discharge containing the solution of arsenic tail gas.
In order to solve the problems of the technologies described above, technical scheme of the present invention is to provide a kind of containing arsenic exhaust gas treating method, it is characterized in that: the method is divided into following 4 steps:
Step 1: make to enter spray column containing arsenic tail gas by flowmeter, be provided with the filler of given shape in spray column, the liquor potassic permanganate that the treatment fluid working concentration of spray column is 0.5%～10% also maintains liquor potassic permanganate pH value in 7～10 scopes; Control the addition of liquor potassic permanganate by oxidation-reduction potential (ORP) analyzer of installing in spray column tower reactor, regulate the addition of potassium hydroxide solution by the pH meter of installing in spray column tower reactor; By circulating pump, liquor potassic permanganate sprayed from top to bottom and in spray column, fully contact absorption containing arsenic tail gas, tail gas after treatment is up to state standards after " GB16297 discharge standard of air pollutants " and exports discharge by tail gas;
Step 2: the solution in spray tower reactor is carried out regularly to quantitatively discharge, discharge every day 2～3 times, discharge the solution of 5%～15% tower reactor liquid level at every turn;
Step 3: the solution unification after discharge is collected in flocculation tank and processed; By adding ferrum sulfuricum oxydatum solutum to making arsenic precipitation in flocculation tank, control pH between 5～9, regulate the addition of potassium hydroxide solution by being arranged on pH meter on flocculation tank.
Step 4: the solution in flocculation tank is continued to filtration cycle, be filtered out " GB8978 integrated wastewater discharge standard " discharge that is up to state standards of waste water after solid filter residue by circulating pump; Surface also has the filter core of waste residue to transfer to the collection and treatment of professional solid waste company.
Preferably, in described step 1, in spray column, the filler of given shape is Raschig ring or arc saddle type filler or arc saddle type net.
Preferably, the flocculation tank of described step 3 is with agitating device.
One provided by the invention is containing arsenic exhaust gas treating method, treatment effeciency is high, treatment process is easy and simple to handle, required cost is low, and the solution containing arsine tail gas is further processed to qualified discharge, there is following beneficial effect: 1, adopt liquor potassic permanganate to absorbing containing arsine tail gas, guaranteed high treatment effeciency; 2, adopt ferrum sulfuricum oxydatum solutum to precipitate to the arsenic-containing waste water having absorbed, under specific pH value, can guarantee that arsenic can precipitate completely; 3, whole treatment process is easy and simple to handle, and required cost is low; 4, realized the system and device of processing containing arsenic tail gas and arsenic-containing waste water integrated; 5, the discharge that has guaranteed tail gas and waste water is significantly less than national standard, reaches the object of environment protection emission.
Accompanying drawing explanation
Fig. 1 is that one provided by the invention contains arsenic exhaust gas treating method flow chart:
Description of reference numerals
1-flowmeter; 2-spray column; 3-circulating pump; 4-pH meter; 5-ORP analyzer; 6-ferrum sulfuricum oxydatum solutum; 7-flocculation tank; 8-solid filter residue; 9-filter; 10-potassium hydroxide solution; 11-liquor potassic permanganate; 12-waste water up to standard; 13-is containing arsenic tail gas; The outlet of 14-tail gas.
The specific embodiment
For the present invention is become apparent, hereby with several preferred embodiments, and coordinate accompanying drawing to be described in detail below.
Embodiment 1
Fig. 1 is that one provided by the invention contains arsenic exhaust gas treating method flow chart, and it is 10ppm that tail gas contains arsine concentration, and air quantity is 60m
3/ min, described one is divided into following 4 steps containing arsenic exhaust gas treating method:
Step 1: making to enter spray column 2 containing arsenic tail gas 13 by flowmeter 1, be provided with the filler of given shape in spray column 2, is Raschig ring or arc saddle type filler or arc saddle type net.The treatment fluid of spray column 2 uses liquor potassic permanganate 11, control the addition of liquor potassic permanganate 11 by the oxidation-reduction potential ORP analyzer 5 of installing in spray column 2 tower reactors, regulate the addition of potassium hydroxide solution 10 by the pH meter 4 of installing in spray column 2 tower reactors, take liquor potassic permanganate 11 concentration that guarantee treatment fluid as 0.5%, pH value maintains 10 left and right, to guarantee best treatment effeciency.
By circulating pump 3, liquor potassic permanganate 11 sprayed from top to bottom and fully contact absorptions containing arsenic tail gas 13 spray column 2 is interior, after tail gas after treatment is up to state standards, exporting 14 by tail gas and discharge.
Step 2: the solution of setting in spray column 2 stills discharges three times every day is discharged the solution of 15% tower reactor liquid level left and right, to prevent that spray column 2 from including gathering of arsenic waste strength at every turn.Can make certain modification to discharge frequency and discharge capacity depending on actual conditions.
Step 3: the solution unification after discharge is collected in flocculation tank 7 and processed, and flocculation tank 7 is with agitating device 15, to guarantee that solution can fully react.To flocculation tank 7, make arsenic precipitation by adding ferrum sulfuricum oxydatum solutum 6, regulate the addition of potassium hydroxide solution 10 by being arranged on pH meter 4 on flocculation tank 7, make ferrum sulfuricum oxydatum solutum concentration be controlled at 2%, the pH value in flocculation tank maintains 9 left and right, guarantees that the arsenic in arsenic-containing waste water can precipitate completely.
Step 4: the solution in flocculation tank 7 is continued to filtration cycle, waste water 12 up to standard is discharged after filter 9 filters out solid filter residue 8 by circulating pump 3.Waste residue on the filter core that contains waste residue is mainly arsenic salt, there is no very large toxicity, can transfer to professional solid waste to process company's centralized collection processing.
Be less than 0.05ppm by the concentration containing arsenic in said method outlet tail gas after treatment, in the waste water solution finally emitting, be less than 0.05ppm containing arsenic concentration, far below the concentration of emission (0.5ppm) of national standard " GB16297 discharge standard of air pollutants " and " GB8978 integrated wastewater discharge standard " restriction, therefore can reach the object of environment protection emission.
Step 1: making to enter spray column 2 containing arsenic tail gas 13 by flowmeter 1, be provided with the filler of given shape in spray column 2, is Raschig ring or arc saddle type filler or arc saddle type net.The treatment fluid of spray column 2 uses liquor potassic permanganate 11, control the addition of liquor potassic permanganate 11 by the oxidation-reduction potential ORP analyzer 5 of installing in spray column 2 tower reactors, regulate the addition of potassium hydroxide solution 10 by the pH meter 4 of installing in spray column 2 tower reactors, take liquor potassic permanganate 11 concentration that guarantee treatment fluid as 10%, pH value maintains 7 left and right, to guarantee best treatment effeciency.
By circulating pump 3, liquor potassic permanganate 11 sprayed from top to bottom and fully contact absorptions containing arsenic tail gas 13 spray column 2 is interior, after tail gas after treatment is up to state standards, exporting 14 by tail gas and discharge.
Step 2: the solution of setting in spray column 2 stills discharges twice every day is discharged the solution of 10% tower reactor liquid level left and right, to prevent that spray column 2 from including gathering of arsenic waste strength at every turn.
Step 3: the solution unification after discharge is collected in flocculation tank 7 and processed, and flocculation tank 7 is with agitating device 15, to guarantee that solution can fully react.To flocculation tank 7, make arsenic precipitation by adding ferrum sulfuricum oxydatum solutum 6, regulate the addition of potassium hydroxide solution 10 by being arranged on pH meter 4 on flocculation tank 7, make ferrum sulfuricum oxydatum solutum concentration be controlled at 10%, the pH value in flocculation tank maintains 5 left and right, guarantees that the arsenic in arsenic-containing waste water can precipitate completely.
Step 4: the solution in flocculation tank 7 is continued to filtration cycle, waste water 12 up to standard is discharged after filter 9 filters out solid filter residue 8 by circulating pump 3.Waste residue on the filter core that contains waste residue is mainly arsenic salt, there is no very large toxicity, can transfer to professional solid waste to process company's centralized collection processing.
Be less than 0.05ppm by the concentration containing arsenic in said method outlet tail gas after treatment, in the waste water solution finally emitting, be less than 0.05ppm containing arsenic concentration, far below the concentration of emission (0.5ppm) of national standard " GB16297 discharge standard of air pollutants " and " GB8978 integrated wastewater discharge standard " restriction, therefore can reach the object of environment protection emission.
Step 1: making to enter spray column 2 containing arsenic tail gas 13 by flowmeter 1, be provided with the filler of given shape in spray column 2, is Raschig ring or arc saddle type filler or arc saddle type net.The treatment fluid of spray column 2 uses liquor potassic permanganate 11, control the addition of liquor potassic permanganate 11 by the oxidation-reduction potential ORP analyzer 5 of installing in spray column 2 tower reactors, regulate the addition of potassium hydroxide solution 10 by the pH meter 4 of installing in spray column 2 tower reactors, take liquor potassic permanganate 11 concentration that guarantee treatment fluid as 5%, pH value maintains 8 left and right, to guarantee best treatment effeciency.
By circulating pump 3, liquor potassic permanganate 11 sprayed from top to bottom and fully contact absorptions containing arsenic tail gas 13 spray column 2 is interior, after tail gas after treatment is up to state standards, exporting 14 by tail gas and discharge.
Step 2: the solution of setting in spray column 2 stills discharges twice every day is discharged the solution of 5% tower reactor liquid level left and right, to prevent that spray column 2 from including gathering of arsenic waste strength at every turn.
Step 3: the solution unification after discharge is collected in flocculation tank 7 and processed, and flocculation tank 7 is with agitating device 15, to guarantee that solution can fully react.To flocculation tank 7, make arsenic precipitation by adding ferrum sulfuricum oxydatum solutum 6, regulate the addition of potassium hydroxide solution 10 by being arranged on pH meter 4 on flocculation tank 7, make ferrum sulfuricum oxydatum solutum concentration be controlled at 5%, the pH value in flocculation tank maintains 7 left and right, guarantees that the arsenic in arsenic-containing waste water can precipitate completely.
Step 4: the solution in flocculation tank 7 is continued to filtration cycle, waste water 12 up to standard is discharged after filter 9 filters out solid filter residue 8 by circulating pump 3.Waste residue on the filter core that contains waste residue is mainly arsenic salt, there is no very large toxicity, can transfer to professional solid waste to process company's centralized collection processing.
Be less than 0.05ppm by the concentration containing arsenic in said method outlet tail gas after treatment, in the waste water solution finally emitting, be less than 0.05ppm containing arsenic concentration, far below the concentration of emission (0.5ppm) of national standard " GB16297 discharge standard of air pollutants " and " GB8978 integrated wastewater discharge standard " restriction, therefore can reach the object of environment protection emission.
Claims (3)
1. containing an arsenic exhaust gas treating method, it is characterized in that: the method is divided into following 4 steps:
Step 1: make to enter spray column (2) containing arsenic tail gas (13) by flowmeter (1), in spray column (2), be provided with the filler of given shape, the liquor potassic permanganate (11) that the treatment fluid working concentration of spray column (2) is 0.5%～10% also maintains liquor potassic permanganate (11) pH value in 7～10 scopes; Control the addition of liquor potassic permanganate (11) by the oxidation reduction potential determination instrument (5) of installing in spray column (2) tower reactor, regulate the addition of potassium hydroxide solution (10) by the pH meter (4) of installing in spray column (2) tower reactor; By circulating pump (3), liquor potassic permanganate (11) sprayed from top to bottom and spray column (2) in, fully contact absorption containing arsenic tail gas (13), tail gas after treatment is up to state standards and exports (14) by tail gas after " GB16297 discharge standard of air pollutants " and discharge;
Step 2: the solution in spray column (2) still is carried out regularly to quantitatively discharge, discharge every day 2～3 times, discharge the solution of 5%～15% tower reactor liquid level at every turn;
Step 3: the solution unification after discharge is collected in flocculation tank (7) and processed; To flocculation tank (7), make arsenic precipitation by adding ferrum sulfuricum oxydatum solutum (6), control pH between 5～9, regulate the addition of potassium hydroxide solution (10) by being arranged on pH meter (4) on flocculation tank (7);
Step 4: the solution in flocculation tank (7) is continued to filtration cycle, the waste water (12) by circulating pump (3) after filter (9) filters out solid filter residue (8) be up to state standards " GB8978 integrated wastewater discharge standard " discharge; Surface also has the filter core of waste residue to transfer to the collection and treatment of professional solid waste company.
2. one as claimed in claim 1, containing arsenic exhaust gas treating method, is characterized in that: the filler of the interior given shape of spray column in described step 1 (2) is Raschig ring or arc saddle type filler or arc saddle type net.
3. one as claimed in claim 1, containing arsenic exhaust gas treating method, is characterized in that: the flocculation tank (7) in described step 3 is with agitating device (15).
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| CN201210244219.7A CN102728182B (en) | 2012-07-13 | 2012-07-13 | Treatment method of arsenic-containing tail gas |
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1139588A (en) * | 1996-04-11 | 1997-01-08 | 中国科学院半导体研究所 | Method for treating waste gas containing arsenic and arsenic compound |
| CN101503255A (en) * | 2009-03-23 | 2009-08-12 | 中国科学院生态环境研究中心 | Method for treating heavy metal polluted water by multicomponent composite flocculating setting agent |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1139588A (en) * | 1996-04-11 | 1997-01-08 | 中国科学院半导体研究所 | Method for treating waste gas containing arsenic and arsenic compound |
| CN101503255A (en) * | 2009-03-23 | 2009-08-12 | 中国科学院生态环境研究中心 | Method for treating heavy metal polluted water by multicomponent composite flocculating setting agent |
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