CN109626740A - A kind of biochemical processing method of coking wastewater and wastewater from chemical industry - Google Patents
A kind of biochemical processing method of coking wastewater and wastewater from chemical industry Download PDFInfo
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- CN109626740A CN109626740A CN201811650532.4A CN201811650532A CN109626740A CN 109626740 A CN109626740 A CN 109626740A CN 201811650532 A CN201811650532 A CN 201811650532A CN 109626740 A CN109626740 A CN 109626740A
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F9/00—Multistage treatment of water, waste water or sewage
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
- C02F1/5236—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using inorganic agents
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
- C02F1/54—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using organic material
- C02F1/56—Macromolecular compounds
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F2001/007—Processes including a sedimentation step
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/10—Inorganic compounds
- C02F2101/16—Nitrogen compounds, e.g. ammonia
- C02F2101/163—Nitrates
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/34—Nature of the water, waste water, sewage or sludge to be treated from industrial activities not provided for in groups C02F2103/12 - C02F2103/32
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F3/00—Biological treatment of water, waste water, or sewage
- C02F3/30—Aerobic and anaerobic processes
- C02F3/302—Nitrification and denitrification treatment
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- Hydrology & Water Resources (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Separation Of Suspended Particles By Flocculating Agents (AREA)
Abstract
The present invention provides the biochemical processing method of a kind of coking wastewater and wastewater from chemical industry, using coking wastewater and wastewater from chemical industry hybrid governance, using the difference-complementary of the two, (i.e. wastewater from chemical industry reduces processing NO using the high CODcr of coking wastewater3Carbon source required for-N, and coking wastewater is low using the ammonia nitrogen of wastewater from chemical industry, reduces amount of oxygen required for processing ammonia nitrogen), efficiency is increased, while reducing the consumption of power and medicament, reduces operating cost.Biochemical system uses preaeration tank+preposition preaeration+separation of solid and liquid+coagulation sedimentation method, high treating effect, the various pollutants in coal chemical industry sewage can be effectively removed, end uses embrane method advanced treating, and treated, and waste water can reach industrial circulating cooling water water standard.
Description
Technical field
The present invention relates to environment protection field, the biochemical processing method of specifically a kind of coking wastewater and wastewater from chemical industry.
Background technique
Coal chemical industry sewage is mainly dirty by coking wastewater, coal tar processing sewage, coke-stove gas methanol wastewater, crude benzene refining
Water, polyformaldehyde sewage, adipic acid sewage and sanitary sewage composition, wherein coking wastewater mainly includes that distilled ammonia wastewater, coking are useless
Water, methanol waste water etc., belong to high-concentration organic industrial waste water, further include aliphatic compound, jeterocyclic chemistry in addition to compound of classifying
Object, phenolic substances and polycyclc aromatic compound etc. are closed, phenolic substances therein is easier to be biodegradable, and jeterocyclic chemistry
It closes object and polycyclic ring aromatics is more difficult to degrade；Polyformaldehyde waste water mainly contains formaldehyde, sulfide etc., and wherein formaldehyde is sterilization
Agent has toxic action to biology, the main content that water is reacted and controlled by dosing and removes formaldehyde or reduction formaldehyde；Adipic acid
Major pollutants in waste water are nitrate and COD (chemical oxygen demand, COD), can be by anti-
Nitrobacteria removes nitrate, removes COD by aerobic reaction, but such water reuse denitrification mode removes nitrate and needs
Want a large amount of carbon source.
Coal chemical industry sewage ingredient is more complicated, and organic pollutant not only has phenolic compound, fat compound, polycyclic virtue
Fragrant compounds of group, there are also nitrogenous, oxygen, the heterocyclic compound of sulphur and alcohol aldehyde polymers etc., and inorganic pollution is with cyanide, ammonia
Nitrogen, rhodanide, sulfide, based on ammonium salt, such sewage category high-concentration hardly-degradable and toxic organic industrial sewage.
Coking production operation control is more extensive, and variation water quality is big, and composition mainly includes distilled ammonia wastewater, methanol production waste water
Deng, pollutant complicated composition, concentration is high, toxicity is big, biochemical effects are bad, and main pollutant is COD, ammonia nitrogen；Adipic acid
Etc. Chemical Manufactures operation control it is more exquisite, sewage quality stablizes easy to control, NO3- N concentration is high, if in addition not supplementing carbon
Source meets denitrifying bacteria oxidation NO3- N, total nitrogen is up to standard relatively difficult, but carrys out supplementary carbon source by nutrients such as addition methanol, transports
Row cost is too high.
Coking wastewater and wastewater from chemical industry can be generated in enterprise production process, individually handle coking wastewater and wastewater from chemical industry, effect
Rate is low, and cost is again high, it is therefore desirable to which one kind can both be handled simultaneously, and biochemical treatment coking wastewater and change high-efficient, at low cost
Work method for waste water.
Summary of the invention
In order to solve low efficiency present in current coking wastewater and chemical wastewater biochemical processing, at high cost asks the present invention
Topic provides the method that can carry out biochemical treatment to coking wastewater and wastewater from chemical industry simultaneously, keeps coking wastewater and wastewater from chemical industry raw
It is high, at low cost to change treatment effeciency.
A kind of biochemical processing method of coking wastewater and wastewater from chemical industry, comprising the following steps:
(1) coking wastewater and wastewater from chemical industry are mixed into composite waste and are passed into conditioning tank, the water of balanced composite waste
Matter and regulating pondage；
(2) composite waste after adjusting is sent to aeration tank by elevator pump and carries out preaeration, composite waste discharges part
It is poisonous and harmful to have object and reduce partial organic substances matter；
(3) composite waste after pre- gas explosion is passed through anoxic pond, in the efficient anaerobic bacterium in anoxic pond and composite waste
NO3- N, COD reaction, to remove NO a part of in composite waste3- N and COD, at the same can also improve composite waste can
Biochemical；
(4) composite waste after anoxic pond is passed into aerobic tank, the high-efficiency aerobic bacterium in aerobic tank is useless to mixing
Water carries out oxygenolysis；
(5) composite waste after aerobic tank is precipitated into 1-5h, composite waste is separated into mixing by entering secondary settling tank
Liquid and sludge, sludge reflux to preaeration tank, anoxic pond and aerobic tank；
(6) mixed liquor after secondary settling tank is passed into coagulative precipitation tank, flocculant is added, removed outstanding in mixed liquor
Floating object obtains advanced treating waste water.
Specifically, preaeration tank uses aerobic deflector type structure, is internally provided with baffle plate, and baffle plate is by composite waste
In suspended impurity removal, to reduce composite waste turbidity, microporous aeration device, micropore is arranged in aerobic deflector type structural base
The proprietary microorganism of addition and carrier in aerator, water conservancy residence time of the composite waste in preaeration tank are 12-16h.In advance
The major function of aeration tank is the noxious materials such as removal composite waste COD, phenol, cyanogen, sulphur, and COD is greatly lowered, and is reduced to nitre
The inhibition of change-denitrification microbial inoculum, to avoid pre- gas explosion biological treatment from consuming carbon source excessively, the water conservancy residence time is extremely important, together
When can rationally adjust the removal efficiency of COD by the control of aeration quantity.Aerobic deflector type structure can be good at controlling microorganism
To the degradation process of organic matter, being maintained at a certain specific degradation period has its corresponding microbial flora, meanwhile, aerobic baffling
Formula structure can be good at reaching the cured effect of microorganism.
Specifically, aerobic tank is divided into a sequentially connected aerobic pond and aerobic two pond, and anoxic pond water outlet overflow enters aerobic
One pond, removes rest COD, and aerobic pond water outlet enters aerobic two pond, carries out nitration reaction, make NH3- H is fully converted to NO3 -And
Degrade overwhelming majority COD, wherein the hydraulic detention time in an aerobic pond is 8-16h, and the hydraulic detention time in aerobic two pond is
16-32h。
Specifically, an aerobic pond uses aerobic deflector type structure, and bottom setting microporous aeration device simultaneously adds carrier；It is aerobic
Microporous aeration device is arranged in two bottom of pond portion, adds proprietary microorganism and carrier, by adding alkali to control pH value.
Specifically, anoxic pond uses anoxic deflector type structure, is internally provided with baffle plate, the effect of baffle plate is by anoxic
Water outlet entrained efficient anaerobic bacterium in pond is deposited in anoxic pond, and composite waste flows into aerobic tank, the high-efficiency aerobic bacterium in aerobic tank
Kind by organic substance oxygenolysis, thus reduce composite waste COD and BOD (biochemical oxygen demand,
BOD), make purification of water quality.
Specifically, preaeration tank water outlet enters anoxic pond with aerobic tank nitrification liquid recirculation water together, completes denitrifying function
It can, wherein reflux ratio 100%-200%, hydraulic detention time 16-32h.
Specifically, flocculant M180, ferric sulfate, aluminum sulfate, polysilicon acid, poly-silicic acid iron sulfate, poly- phosphorus iron chloride, poly- phosphorus
One of aluminium chloride, ferric-polysilicate, polyacrylamide, methacrylic acid.
Coal chemical industry sewage coking wastewater with wastewater from chemical industry there is otherness to have compatible complementarity, coking wastewater and change simultaneously
Work waste water blending processing, the two can mutually promote, and biochemical treatment system runnability can be made more preferable, at the same reduce operation at
This.Coking wastewater COD higher and NH after wastewater from chemical industry ammonia still process3- N (ammonia-nitrogen content index) is still higher, wastewater from chemical industry NH3- N is basic
It is not required to remove；Coking wastewater NO3- N (nitrate nitrogen) is that nitrifier nitration reaction generates, and wastewater from chemical industry raw water is exactly to contain largely
NO3-N；Wastewater from chemical industry reduces operation processing NO using the high CODcr of coking wastewater (dichromate oxidizability)3Carbon required for-N
The offer in source, and the NH of coking wastewater3- N is high, wastewater from chemical industry ammonia nitrogen is low, reduces oxygen required for Treatment of Coking Effluent ammonia nitrogen
Tolerance,
Compared with prior art, the characteristics of present invention is for the high COD of coking wastewater and wastewater from chemical industry low ammonia nitrogen, using coking
Waste water and wastewater from chemical industry hybrid governance, using the difference-complementary of the two, (i.e. wastewater from chemical industry is using at the high CODcr reduction of coking wastewater
Manage NO3Carbon source required for-N, and coking wastewater is low using the ammonia nitrogen of wastewater from chemical industry, reduces oxygen required for processing ammonia nitrogen
Amount), efficiency is increased, while reducing the consumption of power and medicament, reduces operating cost.Biochemical system uses preaeration tank
+ preposition preaeration+separation of solid and liquid+coagulation sedimentation method, high treating effect can effectively remove the various pollutions in coal chemical industry sewage
Object, end use embrane method advanced treating, and treated, and waste water can reach industrial circulating cooling water water standard.
Specific embodiment
For a further understanding of the present invention, the preferred embodiment of the invention is described below with reference to embodiment, still
It should be appreciated that these descriptions are only further explanation the features and advantages of the present invention, rather than to the claims in the present invention
Limitation.
A kind of biochemical processing method of coking wastewater and wastewater from chemical industry, comprising the following steps:
(1) coking wastewater and wastewater from chemical industry are mixed into composite waste and are passed into conditioning tank, the water of balanced composite waste
Matter and regulating pondage；
(2) composite waste after adjusting is sent to aeration tank by elevator pump and carries out preaeration, composite waste discharges part
It is poisonous and harmful to have object and reduce partial organic substances matter, hydraulic detention time 12h；
(3) composite waste after pre- gas explosion is passed through anoxic pond, in the efficient anaerobic bacterium in anoxic pond and composite waste
NO3- N, COD reaction, to remove NO a part of in composite waste3- N and COD, hydraulic detention time are for 24 hours；
(4) composite waste after anoxic pond is passed into aerobic tank, the high-efficiency aerobic bacterium in aerobic tank is useless to mixing
Water carries out oxygenolysis, wherein the hydraulic detention time in an aerobic pond is 12h, the hydraulic detention time in aerobic two pond is for 24 hours；
(5) composite waste after aerobic tank is precipitated into 2h, composite waste is separated into mixed liquor by entering secondary settling tank
And sludge, sludge reflux to preaeration tank, anoxic pond and aerobic tank, wherein the reflux of pre-exposure pond water outlet and aerobic tank nitrification liquid
Than being 150%；
(6) mixed liquor after secondary settling tank is passed into coagulative precipitation tank, M180 is added, remove the suspension in mixed liquor
Object obtains advanced treating waste water.
The results are shown in Table 1, CODcr, NH3The handling rate of-N and phenol is up to 93.7%, 94.1% and 99.9%, has very
High treatment effeciency.
1 biochemical system Inlet and outlet water water quality of table
Claims (6)
1. the biochemical processing method of a kind of coking wastewater and wastewater from chemical industry, comprising the following steps:
(1) coking wastewater and wastewater from chemical industry are mixed into composite waste and are passed into conditioning tank, the water quality of balanced composite waste is simultaneously
Regulating pondage；
(2) composite waste after adjusting is sent to aeration tank by elevator pump and carries out preaeration, it is toxic that composite waste discharges part
Nocuousness has object and reduces partial organic substances matter；
(3) composite waste after pre- gas explosion is passed through anoxic pond, the efficient anaerobic bacterium in anoxic pond and the NO in composite waste3-
N, COD reacts, to remove NO a part of in composite waste3- N and COD；
(4) composite waste after anoxic pond is passed into aerobic tank, the high-efficiency aerobic bacterium in aerobic tank to composite waste into
Row oxygenolysis；
(5) by the composite waste after aerobic tank by entering secondary settling tank, precipitate 1-5h, composite waste be separated into mixed liquor and
Sludge, sludge reflux to preaeration tank, anoxic pond and aerobic tank；
(6) mixed liquor after secondary settling tank is passed into coagulative precipitation tank, flocculant is added, remove the suspension in mixed liquor
Object obtains advanced treating waste water.
2. the biochemical processing method of a kind of coking wastewater and wastewater from chemical industry according to claim 1, which is characterized in that described
Preaeration tank uses aerobic deflector type structure, is internally provided with baffle plate, baffle plate removes the suspended impurity in composite waste
It removes, to reduce composite waste turbidity, microporous aeration device, addition in microporous aeration device is arranged in aerobic deflector type structural base
Proprietary microorganism and carrier, water conservancy residence time of the composite waste in preaeration tank are 12-16h.
3. the biochemical processing method of a kind of coking wastewater and wastewater from chemical industry according to claim 1, which is characterized in that described
Aerobic tank is divided into a sequentially connected aerobic pond and aerobic two pond, and anoxic pond is discharged overflow and enters an aerobic pond, and removing is remaining
COD, aerobic pond water outlet enter aerobic two pond, carry out nitration reaction, make NH3- H is fully converted to NO3And the overwhelming majority of degrading
COD, wherein the hydraulic detention time in an aerobic pond is 8-16h, and the hydraulic detention time in aerobic two pond is 16-32h.
4. the biochemical processing method of a kind of coking wastewater and wastewater from chemical industry according to claim 3, which is characterized in that described
An aerobic pond uses aerobic deflector type structure, and bottom setting microporous aeration device simultaneously adds carrier；Aerobic two bottom of pond portion is set
Microporous aeration device is set, proprietary microorganism and carrier are added, by adding alkali to control pH value.
5. the biochemical processing method of a kind of coking wastewater and wastewater from chemical industry according to claim 1, which is characterized in that pre-exposure
The water outlet of gas pond enters anoxic pond with aerobic tank nitrification liquid recirculation water together, completes denitrifying function, wherein the reflux ratio is
100%-200%, hydraulic detention time 16-32h.
6. the biochemical processing method of a kind of coking wastewater and wastewater from chemical industry according to claim 1, which is characterized in that described
Flocculant is M180, ferric sulfate, aluminum sulfate, polysilicon acid, poly-silicic acid iron sulfate, poly- phosphorus iron chloride, poly- phosphorus aluminium chloride, polysilicon acid
One of iron, polyacrylamide, methacrylic acid.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022143243A1 (en) * | 2020-12-30 | 2022-07-07 | 中冶焦耐(大连)工程技术有限公司 | Coking wastewater treatment system and process for realizing gradient utilization of powdered activated carbon |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2013078639A1 (en) * | 2011-11-30 | 2013-06-06 | Rohm And Haas Company | Coking wastewater treatment |
| CN206580707U (en) * | 2017-03-16 | 2017-10-24 | 北京志能祥赢节能环保科技股份有限公司 | A kind of coking chemical waste water total system |
| CN108911440A (en) * | 2018-09-20 | 2018-11-30 | 河南小威环境科技有限公司 | A kind of method and system handling coking wastewater |
-
2018
- 2018-12-31 CN CN201811650532.4A patent/CN109626740A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2013078639A1 (en) * | 2011-11-30 | 2013-06-06 | Rohm And Haas Company | Coking wastewater treatment |
| CN206580707U (en) * | 2017-03-16 | 2017-10-24 | 北京志能祥赢节能环保科技股份有限公司 | A kind of coking chemical waste water total system |
| CN108911440A (en) * | 2018-09-20 | 2018-11-30 | 河南小威环境科技有限公司 | A kind of method and system handling coking wastewater |
Non-Patent Citations (1)
| Title |
|---|
| 段炯等: "煤化工废水生物处理技术研究", 《化工管理》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022143243A1 (en) * | 2020-12-30 | 2022-07-07 | 中冶焦耐(大连)工程技术有限公司 | Coking wastewater treatment system and process for realizing gradient utilization of powdered activated carbon |
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Application publication date: 20190416 |