CN102951719B - Method for treating nitrobenzene wastewater by utilizing pyrrhotite fixed bed - Google Patents
Method for treating nitrobenzene wastewater by utilizing pyrrhotite fixed bed Download PDFInfo
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- CN102951719B CN102951719B CN201210558919.3A CN201210558919A CN102951719B CN 102951719 B CN102951719 B CN 102951719B CN 201210558919 A CN201210558919 A CN 201210558919A CN 102951719 B CN102951719 B CN 102951719B
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- pyrrhotite
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- waste water
- nitrobenzene
- fixed bed
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Abstract
The invention discloses a method for treating nitrobenzene wastewater by utilizing a pyrrhotite fixed bed, and belongs to the technical field of sewage treatment. The method comprises three steps of: (1), the preparation of a raw material: crushing pyrrhotite until a particle size is less than 30 mm, cleaning pyrrhotite particles clearly, removing oxides and other dirt on the surfaces of the pyrrhotite particles, and directly putting the pyrrhotite particles in a reactor to form the pyrrhotite fixed bed; (b), the start of the reactor: introducing the nitrobenzene wastewater into the reactor in the step (a), periodically sampling, detecting a water quality index, and completing the start of the reactor after the removal rate of nitrobenzene is stable; and (c), the running of the reactor: introducing the wastewater to be treated into the reactor completing the starting, controlling the running parameters of the reactor according to the step (b), and discharging the treated nitrobenzene wastewater. By using the method, the nitrobenzene is converted into corresponding phenylamine by adopting the natural pyrrhotite, so that the pretreatment on the nitrobenzene wastewater is realized, and the method has the advantages of small floor area, simplenessicity in operation and low cost.
Description
Technical field
The invention belongs to technical field of sewage, specifically, relate to a kind of method of utilizing pyrrhotite fixed bed treatment of Nitrobenzene waste water.
Background technology
Oil of mirbane is widely used in the industry such as national defence, medicine, agricultural chemicals, printing and dyeing and plastics, is a kind of important industrial chemicals.But its chemical structure is more stable, and biodegradability is poor, belong to the organism of difficult for biological degradation, be difficult for directly adopting biological process to process.If by physico-chemical processes by oil of mirbane change into toxicity little, should biodegradable aniline, then by biological process by its permineralization, can make discharged wastewater met the national standard.In practical application, the chemical methods that adopt carry out pre-treatment to high density nitrobenzene-containing waste water more, to reduce the impact load to biochemistry pool.But the treatment technology of existing p-nitrophenyl waste water all exists cost high, the problem of cannot big area using.
Method for transformation based on transition element Fe in numerous methods that oil of mirbane are converted into aniline is the focus of research at present.Zero-valent Iron (Fe
0), surface contains Fe(II) or absorption Fe(II) material can effectively remove the difficult degradation toxic organic pollutants such as nitro-aromatic, halohydrocarbon.The oil of mirbane of Zero-valent Iron reduction is at present the more method of studying in pre-treatment nitrobenzene waste water.Though Zero-valent Iron reduction oil of mirbane has fast, the practical feature of speed of response, its cost is higher.There are some researches show Fe
0surface is at process HS
-the reducing activity of processing the FeS forming significantly strengthens, and the speed of removing halohydrocarbon greatly improves.
The applicant has applied for that on 04 01st, 2012 a name is called a kind of patent document that utilizes the method for Iron sulfuret pre-treatment nitrobenzene-containing waste water, Chinese Patent Application No.: 2012100953696, open day: on 07 25th, 2012, this patent disclosed employing Iron sulfuret and carried out the pretreated method of nitrobenzene waste water.The steps include: that (1) is crushed to granularity by Iron sulfuret is 50-60 order, and it is stand-by by washing or pickling, to expose Iron sulfuret unsalted surface; (2) Iron sulfuret after processing is joined in reaction vessel; (3) nitrobenzene waste water is joined in above-mentioned reaction vessel, wherein in reaction vessel, Iron sulfuret is not less than 30:1 with the ratio of the mass concentration of oil of mirbane, and the mass concentration of Iron sulfuret is not less than 3.6 g/L; (4) reaction vessel is placed in to anaerobism or anaerobic environment, Iron sulfuret is mixed with nitrobenzene waste water, after hybrid reaction 60 ~ 180min, complete the pre-treatment of nitrobenzene waste water.This patent provides the novel method of utilizing synthetic Iron sulfuret treatment of Nitrobenzene.But Iron sulfuret used is chemical products, and cost is higher.Using method is intermittently batch use, uses and is limited to, and pH is had relatively high expectations while using.And the pH value fluctuation ratio of general nitrobenzene waste water is larger, so being not suitable for big area, this method uses.Therefore need to find a kind of cost low and can process the technology of the nitrobenzene waste water that pH value fluctuation ratio is larger.
In fact, FeS is on earth with pyrrhotite (Fe
(1-x)s, x is between 0～0.1) form exist, it is natural mineral widely distributed, cheap and easy to get on the earth.Natural pyrrhotite main component is Iron sulfuret, and still wherein the ratio of iron and sulphur is usually less than 1:1, and compositing range is Fe
7s
8～Fe
11s
12, its structure is the NiA from standard
5lattice development, has multiple crystalline form, wherein iron atom Fe the most in debt
7s
8have oblique crystal symmetry, some other intermediateness product and FeS have respectively hexagonal crystal and square crystal structure.The pyrrhotite of occurring in nature is usually the mixture of oblique crystal and hexagonal crystal, and owing to existing in crystalline structure, iron is in debt becomes complicated to its chemical property, and the deficit of the iron in crystalline structure causes lower crystal symmetry, thereby has strengthened its reactivity.In addition, in natural pyrrhotite, also there are some unvulcanised ferrous components such as ferric iron, can promote the formation of iron content active compound in natural pyrrhotite and oil of mirbane reaction process.Exactly because the crystalline structure of this uniqueness of natural pyrrhotite with become to be grouped into make it than Iron sulfuret, within the scope of wider pH, to there is stronger response capacity, can react with oil of mirbane.Discarded pyrrhotite, in moistening oxidation that can be spontaneous with contact with air in the situation that, produces acid wastewater in mine, and the water surrounding in mine is caused to serious harm.Utilize the characteristic reduction oil of mirbane of natural pyrrhotite not only can reduce its harm to mine environment, the method for a cheap pre-treatment nitrobenzene waste water is also provided simultaneously.
Summary of the invention
the problem solving
Processing cost for prior art treatment of Nitrobenzene is high, the problem of pH narrow application range, the invention provides a kind of method of utilizing pyrrhotite fixed bed treatment of Nitrobenzene waste water, is a kind of method of pre-treatment nitrobenzene-containing waste water simply effective, with low cost.
technical scheme
In order to address the above problem, the technical solution adopted in the present invention is as follows:
A method of utilizing pyrrhotite fixed bed treatment of Nitrobenzene waste water, the steps include:
(a) raw material is prepared: pyrrhotite is crushed to particle diameter <30 mm, and pyrrhotite particle cleaning is clean, remove oxide on surface and other dirt, be directly placed in reactor and form pyrrhotite fixed bed;
(b) reactor start-up: pass into nitrobenzene waste water in the reactor in step (a), temperature of reaction is controlled as 15-60 ℃, regulate reactor flooding velocity, controlling nitrobenzene waste water is 0.5-2d at the hydraulic detention time of reactor, make pyrrhotite and nitrobenzene waste water be able to fully contact, regularly sampling, surveys its water-quality guideline, after oil of mirbane clearance is stable, complete reactor start-up; ;
(c) reactor operation: continue to pass into pending waste water to completing in the reactor of startup, control reactor operating parameter by step (b), the nitrobenzene waste water discharge after processing.
Preferably, the pyrrhotite in described step (a) is natural pyrrhotite, the particle diameter <10 mm of pyrrhotite particle.
In present method, the transformation efficiency of oil of mirbane raises along with the rising of temperature of reaction, the too low oil of mirbane clearance of temperature is lower, be difficult to apply, although higher temperature may obtain higher treatment effect, but may accelerate the generation of oxides-containing iron precipitation in fixed bed, shorten the work-ing life of fixed bed.
Preferred, in described step (b), nitrobenzene waste water pH value is 2-10.The dissolving of the natural pyrrhotite that water inlet pH is too low in will accelerating solid bed, pH is too high will form at pyrrhotite the oxides-containing irons such as similar patina, is all difficult to form the surface bonding iron system with reduction characteristic, realizes the reduction of p-nitrophenyl.
Preferably, in described step (b), nitrobenzene waste water is 1 d at the hydraulic detention time of reactor.
Preferred, in described step (b), temperature of reaction is 25 ℃.
Principle of the present invention is in reactor, to form natural pyrrhotite fixed bed, utilize the reduction characteristic of natural pyrrhotite uniqueness, and the combined Fe(II that forms of particle surface), the reductive action that has of the characteristic such as the activated precursor compound of tool is reduced to amino benzenes compounds by nitrobenzene compounds, thereby improves its biodegradability.
beneficial effect
Than prior art, the invention provides the method for natural pyrrhotite fixed bed treatment of Nitrobenzene waste water, nitrobenzene compounds in waste water is reduced to aniline category matter, improve the biodegradability of waste water, pre-treatment before being applicable to high nitrobenzene wastewater biochemical and processing and the processing of low-concentration nitrobenzene waste water by means, principal benefits has:
(1) the present invention adopts natural pyrrhotite, nitrobenzene compounds in waste water is reduced to aniline category matter, improve the biodegradability of waste water, pre-treatment before being applicable to high nitrobenzene wastewater biochemical and processing and the processing of low-concentration nitrobenzene waste water by means, there is processing cost low, effective advantage;
(2) the present invention adopts natural pyrrhotite, and pyrrhotite source is wide, cheap, and treatable nitrobenzene waste water pH value reaches 2-10, and p-nitrophenyl wastewater pH is applied widely;
(3) when the present invention reacts, needed pyrrhotite fixed bed reaction apparatus is simple, easy and simple to handle, and processing cost is low;
(4) energy Continuous Wastewater Treatment of the present invention, reaction process is short, do not need outer adding medicine, and cost is low, and treatment effect is good, is easy to through engineering approaches application.
Accompanying drawing explanation
Fig. 1 is reaction unit structural representation of the present invention.
In figure: 1, water tank; 2, pump; 3, reactor; 4, water temperature control device; 5, water outlet.
Embodiment
Below in conjunction with specific embodiment, describe the present invention.
embodiment 1
A kind of method of utilizing pyrrhotite fixed bed treatment of Nitrobenzene waste water, adopt the device in Fig. 1, this device is connected to form successively by water tank 1, pump 2, reactor 3 and water outlet 5, also comprise that water temperature control device 4 controls the temperature of reactor 3, processing for neutral nitrobenzene waste water, the steps include:
(a) raw material is prepared: pyrrhotite is crushed to particle diameter <30 mm, and pyrrhotite particle cleaning is clean, remove oxide on surface and other dirt, be directly placed in reactor 3 and form pyrrhotite fixed bed; The nitrobenzene waste water that the present embodiment is processed is prepared by oil of mirbane and tap water, water sample pH=6.75, and initial nitro phenenyl concentration is 22 mg/L, it is stand-by that nitrobenzene waste water is put into water tank 1.
(b) reactor start-up: the nitrobenzene waste water in water tank 1 is passed in reactor 3 by pump 2, pyrrhotite is fully contacted with nitrobenzene waste water, water temperature control device 4 makes temperature of reaction remain on 25 ℃ ± 2 ℃, regulate reactor water inlet flow velocity, controlling nitrobenzene waste water is 1 d at the hydraulic detention time of reactor 3, every 48 h samplings, survey its water-quality guideline, after oil of mirbane clearance is stable, complete reactor 3 and start, sampling result is as shown in table 1 below.
(c) reactor operation: continue to pass into pending waste water to completing in the reactor 3 of startup, by step (b), control reactor operating parameter, the nitrobenzene waste water after processing is discharged by water outlet 5, and water outlet oil of mirbane is lower than 2 mg/l, oil of mirbane clearance is 91%, and installs stable.
Table 1
| Sampling number of times | 1 | 2 | 3 | 4 |
| Water outlet NB(mg/L) | 3.6 | 3.3 | 1.98 | 1.96 |
embodiment 2
This invention is processed for acid nitrobenzene waste water, adopts the device in Fig. 1, the steps include:
(a) raw material is prepared: pyrrhotite is crushed to particle diameter <10 mm, and pyrrhotite particle cleaning is clean, remove oxide on surface and other dirt, be directly placed in reactor 3 and form pyrrhotite fixed bed; Nitrobenzene waste water is prepared by oil of mirbane and tap water, water sample pH=2.00, and initial nitro phenenyl concentration is 24 mg/L,
(b) reactor start-up: pass into nitrobenzene waste water in the reactor 3 in step (a), pyrrhotite is fully contacted with nitrobenzene waste water, it is 15 ℃ that temperature of reaction is controlled, regulate reactor 3 water inlet flow velocitys, controlling nitrobenzene waste water is 1 d at the hydraulic detention time of reactor 3, every 24 h samplings, survey its water-quality guideline, after oil of mirbane clearance is stable, complete reactor 3 and start, sampling result is as shown in table 2 below;
(c) reactor operation: continue to pass into pending waste water to completing in the reactor 3 of startup, control reactor 3 operating parameters by step (b), the nitrobenzene waste water discharge after processing.Water outlet oil of mirbane is lower than 1.6 mg/l, and oil of mirbane clearance is 93%, and installs stable.
Table 2
| Sampling number of times | 1 | 2 | 3 | 4 |
| Water outlet NB(mg/L) | 1.75 | 1.65 | 1.56 | 1.55 |
embodiment 3
For alkaline nitrobenzene waste water, process, with embodiment 1, difference is nitrobenzene waste water pH=10, and initial nitro phenenyl concentration is 22 mg/L, and water temperature remains on 60 ℃.Regulate flooding velocity, controlling nitrobenzene waste water is 0.5 d at the hydraulic detention time of reactor, unloading phase every 12 h, get sample one time, result is as shown in table 3, after the normal operation of reactor 3, water outlet oil of mirbane is lower than 1.8 mg/l, and oil of mirbane clearance is 92%, and installs stable.
Table 3
| Sampling number of times | 1 | 2 | 3 | 4 |
| Water outlet NB(mg/L) | 3.2 | 2.5 | 1.9 | 1.8 |
embodiment 4
The present embodiment is the processing for high water temperature nitrobenzene waste water, and with embodiment 1, difference is nitrobenzene waste water pH=6.56, and initial nitro phenenyl concentration is 17 mg/L, and water temperature remains on 60 ℃.Regulate reactor 3 water inlet flow velocitys, pyrrhotite is fully contacted with processing waste water, controlling hydraulic detention time is 1 d, unloading phase, every 48 h, get sample one time, measure its water-quality guideline, sampling result is as shown in table 4.After reactor 3 is stable, water outlet oil of mirbane is lower than 0.2 mg/l, and oil of mirbane clearance is 99%, and installs stable.
Table 4
| Sampling number of times | 1 | 2 | 3 | 4 |
| Water outlet NB(mg/L) | 0.27 | 0.15 | 0.14 | 0.15 |
embodiment 5
The present embodiment is to process for actual nitrobenzene wastewater, and operation steps is with embodiment 1, and difference is that test waste water used is from chemical plant, Zhengzhou, regulate water sample pH=5.65, in waste water, initial nitrobenzene matters concentration is 15 mg/L, and water temperature remains on 25 ℃, and hydraulic detention time is 2 d.Water outlet nitrobenzene matters is lower than 0.5 mg/l, and oil of mirbane clearance is 99%, and installs stable.
Claims (5)
1. a method of utilizing pyrrhotite fixed bed treatment of Nitrobenzene waste water, the steps include:
(a) raw material is prepared: pyrrhotite is crushed to particle diameter <30 mm, and pyrrhotite particle cleaning is clean, remove oxide on surface and other dirt, be directly placed in reactor and form pyrrhotite fixed bed;
(b) reactor start-up: pass into nitrobenzene waste water in the reactor in step (a), temperature of reaction is controlled as 15-60 ℃, regulate reactor flooding velocity, controlling nitrobenzene waste water is 0.5-2 d at the hydraulic detention time of reactor, make pyrrhotite and nitrobenzene waste water be able to fully contact, regularly sampling, surveys its water-quality guideline, after oil of mirbane clearance is stable, complete reactor start-up;
(c) reactor operation: continue to pass into pending waste water to completing in the reactor of startup, control reactor operating parameter by step (b), the nitrobenzene waste water discharge after processing.
2. according to letter of authorization, require a kind of method of utilizing pyrrhotite fixed bed treatment of Nitrobenzene waste water described in 1, it is characterized in that, pyrrhotite in described step (a) is natural pyrrhotite, the particle diameter <10 mm of pyrrhotite particle.
3. according to letter of authorization, require a kind of method of utilizing pyrrhotite fixed bed treatment of Nitrobenzene waste water described in 1, it is characterized in that, in described step (b), nitrobenzene waste water pH value is 2-10.
4. according to letter of authorization, require a kind of method of utilizing pyrrhotite fixed bed treatment of Nitrobenzene waste water described in 1, it is characterized in that, in described step (b), nitrobenzene waste water is 1 d at the hydraulic detention time of reactor.
5. according to letter of authorization, require a kind of method of utilizing pyrrhotite fixed bed treatment of Nitrobenzene waste water described in any one in 1-4, it is characterized in that, in described step (b), temperature of reaction is 25 ℃.
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| CN106242013B (en) * | 2016-09-20 | 2020-04-14 | 绍兴文理学院 | Method for treating heavy metal ion-containing wastewater by mixing natural pyrrhotite and zero-valent iron |
| CN106348419B (en) * | 2016-09-20 | 2020-04-14 | 绍兴文理学院 | Method for repairing polluted wastewater by using natural pyrrhotite and zero-valent iron as PRB active filler |
| CN107304075B (en) * | 2017-07-06 | 2019-12-13 | 南京大学 | Wastewater treatment method for synchronously removing nitrogen, phosphorus and ammonia nitrogen |
| CN109052641B (en) * | 2018-09-05 | 2020-12-18 | 南京大学 | Coupling filler autotrophic denitrification biological filter and application |
| CN112429842B (en) * | 2020-11-27 | 2023-06-16 | 南通大学 | Treatment method for FeS-driven anaerobic reduction of nitroaromatic compound wastewater |
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| CN101428895A (en) * | 2008-11-28 | 2009-05-13 | 同济大学 | Method for pretreating nitrobenzene-containing wastewater by employing steel scoria-bivalent iron ion system |
| CN101514070A (en) * | 2009-04-07 | 2009-08-26 | 达斯玛环境科技（北京）有限公司 | Disposal technique of nitrobenzene-containing sewage |
| CN102060368A (en) * | 2010-11-24 | 2011-05-18 | 南京大学 | Method for improving utilization rate of zero-valent iron in zero-valent iron pretreatment of chemical wastewater |
| CN102603050A (en) * | 2012-04-01 | 2012-07-25 | 南京大学 | Method for preprocessing nitrobenzene-contained waste water by ferrous sulfide |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0249798B2 (en) * | 1988-01-28 | 1990-10-31 | Kogyo Gijutsuin | JUKIKAGOBUTSUGANJUSUINOSHORIHOHO |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101428895A (en) * | 2008-11-28 | 2009-05-13 | 同济大学 | Method for pretreating nitrobenzene-containing wastewater by employing steel scoria-bivalent iron ion system |
| CN101514070A (en) * | 2009-04-07 | 2009-08-26 | 达斯玛环境科技（北京）有限公司 | Disposal technique of nitrobenzene-containing sewage |
| CN102060368A (en) * | 2010-11-24 | 2011-05-18 | 南京大学 | Method for improving utilization rate of zero-valent iron in zero-valent iron pretreatment of chemical wastewater |
| CN102603050A (en) * | 2012-04-01 | 2012-07-25 | 南京大学 | Method for preprocessing nitrobenzene-contained waste water by ferrous sulfide |
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| Title |
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| JP平1-194993A 1989.08.04 |
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