CN111099782A - Advanced treatment method for coal chemical industry wastewater - Google Patents

Advanced treatment method for coal chemical industry wastewater Download PDF

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Publication number
CN111099782A
CN111099782A CN201811250197.9A CN201811250197A CN111099782A CN 111099782 A CN111099782 A CN 111099782A CN 201811250197 A CN201811250197 A CN 201811250197A CN 111099782 A CN111099782 A CN 111099782A
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wastewater
coal chemical
chemical industry
water
treated water
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周秋成
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Yulin Coal Chemical Industry Promotion Center
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Yulin Coal Chemical Industry Promotion Center
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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
    • 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
    • C02F1/001—Processes for the treatment of water whereby the filtration technique is of importance
    • 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
    • C02F1/44—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
    • 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
    • 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
    • C02F1/5263—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using natural chemical compounds
    • 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
    • C02F1/5281—Installations for water purification using chemical agents
    • 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
    • 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
    • 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
    • C02F1/72—Treatment of water, waste water, or sewage by oxidation
    • C02F1/78—Treatment of water, waste water, or sewage by oxidation with ozone
    • 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
    • C02F2003/001—Biological treatment of water, waste water, or sewage using granular carriers or supports for the microorganisms
    • C02F2003/003—Biological treatment of water, waste water, or sewage using granular carriers or supports for the microorganisms using activated carbon or the like
    • 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
    • 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
    • C02F2101/20—Heavy metals or heavy metal compounds
    • 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
    • C02F2101/30—Organic compounds
    • 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
    • C02F2101/30—Organic compounds
    • C02F2101/34—Organic compounds containing oxygen
    • C02F2101/345—Phenols
    • 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
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2209/00—Controlling or monitoring parameters in water treatment
    • C02F2209/08—Chemical Oxygen Demand [COD]; Biological Oxygen Demand [BOD]
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2209/00—Controlling or monitoring parameters in water treatment
    • C02F2209/14—NH3-N
    • 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
    • C02F3/34—Biological treatment of water, waste water, or sewage characterised by the microorganisms used

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  • Life Sciences & Earth Sciences (AREA)
  • Hydrology & Water Resources (AREA)
  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Water Supply & Treatment (AREA)
  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Activated Sludge Processes (AREA)
  • Separation Of Suspended Particles By Flocculating Agents (AREA)

Abstract

The invention relates to a coal chemical industry wastewater advanced treatment method, which comprises the following steps: introducing the coking wastewater subjected to the common treatment into a flocculation tank and adding a flocculating agent; performing membrane separation on the coal chemical wastewater after biochemical treatment to obtain primary treated water; introducing acetic acid and ozone into the primary treated water for aeration oxidation to obtain secondary treated water; treating the secondary water in a third stage in an immobilized biological activated carbon reactor; and filtering the third-stage treated water by a membrane to obtain purified water. The invention can effectively remove COD in the wastewater, realizes zero discharge of the wastewater, and has low operation cost and simple flow.

Description

Advanced treatment method for coal chemical industry wastewater
Technical Field
The invention belongs to the technical field of environmental protection, relates to a wastewater treatment method, and particularly relates to a coal chemical wastewater advanced treatment method.
Background
The coal chemical industry wastewater has the characteristics of various components, large quantity of toxic substances such as a large quantity of suspended particles and the like, high toxicity, high concentration and chromaticity and the like, although the components in the wastewater are different due to the influence of various factors, the overall environment pollution degree is the same, the pollution degree is high, and the problem is difficult to effectively solve; COD in the coal chemical industry wastewater is generally about 5000mg/L, ammonia nitrogen is 200-500 mg/L, organic pollutants contained in the wastewater comprise phenols, polycyclic aromatic compounds, heterocyclic compounds containing nitrogen, oxygen and sulfur and the like, wherein the phenols and the benzenes belong to easily degradable organic matters, pyrrolides, naphthalenes, furans and amidines belong to degradable organic matters, and pyrrolides, carbazoles, biphenyls, terphenyls and the like belong to difficultly degradable organic matters, so the coal chemical industry wastewater is typical industrial wastewater containing the difficultly degradable organic compounds, and the COD of the wastewater discharged outside the coal chemical industry is difficult to reach the first-level standard.
At present, coking wastewater in coal chemical industry at home and abroad is only treated by common coal chemical wastewater, and the treatment process flow of the coking wastewater in the common coal chemical industry mainly comprises oil removal, dephenolization, ammonia distillation and biological treatment, although phenol, cyanogen, sulfide and BOD in the effluent water5The pollutants can basically reach or approach the emission standard, but COD, total phenol and ammonia nitrogen pollutants still can not reach the emission standard. The treatment of oil refining wastewater in coal chemical industry mostly adopts three sets of traditional treatment processes, namely oil separation, flotation and biochemical treatment, but along with the increasing complexity of crude oil properties and the increasingly strict water quality discharge standard of oil refining industry, the oil refining wastewater after the traditional secondary treatment cannot meet the requirements of the current water quality discharge standard; therefore, the problem of advanced treatment of coal chemical wastewater becomes a hot spot again.
Disclosure of Invention
In order to solve the technical problems, the invention provides a coal chemical industry wastewater advanced treatment method which can effectively remove COD in wastewater, realize zero discharge of wastewater, and has low operation cost and simple flow.
The technical scheme adopted by the invention is as follows:
a coal chemical industry wastewater advanced treatment method is characterized in that: the advanced treatment method of the coal chemical industry wastewater comprises the following steps:
introducing coking wastewater subjected to common treatment into a flocculation tank and adding a flocculating agent;
secondly, performing membrane separation on the coal chemical wastewater after biochemical treatment to obtain primary treated water;
thirdly, introducing acetic acid and ozone into the primary treated water for aeration oxidation to obtain secondary treated water;
(IV) treating the secondary water in a third stage in an immobilized biological activated carbon reactor;
and (V) filtering the third-stage treated water by a membrane to obtain purified water.
The flocculant comprises the following components in parts by mass:
Figure BDA0001841502540000021
the balance being a matrix which is a combination of one or more of chitosan, modified starch, modified cellulose, lignin or gum.
The silicate is aluminum silicate or ferric silicate; the coagulant aid is one or a mixture of at least two of polymaleic anhydride, maleic acid-acrylic acid copolymer, acrylic acid-ethyl acrylate copolymer and guar gum.
The residence time in the membrane separation reactor is 2-24 h.
The acetic acid is industrial glacial acetic acid, and the adding ratio of the mass of the acetic acid to the COD amount of raw water is 0.25-0.4: 1.
The temperature of the water in the immobilized biological activated carbon reactor is 21-25 ℃.
The invention has the following technical effects:
1. the invention organically combines the membrane separation technology and the biological treatment technology, and can well remove COD and organic matters in the wastewater.
2. According to the invention, acetic acid is used as a co-metabolism substrate for aeration before the wastewater is introduced into the immobilized biological activated carbon reactor, so that the advantages of convenience in maintenance, stable effect, low cost and the like are achieved, and the concentration of dissolved oxygen in the water body is increased.
3. The method for deeply treating the coal chemical industry wastewater is simple, the deep treatment time is as short as 3-5 hours, and the cost is low.
4. The ozone oxidation can oxidize and degrade macromolecular nondegradable organic matters in the water body into low-degree or nontoxic micromolecular substances, and even directly degrade the macromolecular nondegradable organic matters into CO2And H2O, near complete mineralization.
5. The invention can effectively remove heavy metal ions in the wastewater through membrane filtration, further remove suspended matters, COD and organic matters which are difficult to degrade in the wastewater, and realize zero discharge of the coal chemical wastewater.
6. The flocculant adopted by the invention has stable performance, less input amount and better treatment effect.
Detailed Description
Specific implementations of the present invention will now be further described with reference to examples.
The advanced treatment method of the coal chemical industry wastewater provided by the invention comprises the following steps:
introducing coking wastewater subjected to common treatment into a flocculation tank, and adding a flocculant, wherein the flocculant comprises the following components in parts by mass: 13-18 parts of acrylamide; 20-30 parts of tetraethylenepentamine; 25-30 parts of silicate; 8-15% of zinc sulfate; 0.2-0.4% of coagulant aid; the balance is matrix which is one or the combination of chitosan, modified starch, modified cellulose, lignin or gum; the silicate is aluminum silicate or ferric silicate; the coagulant aid is one or a mixture of at least two of polymaleic anhydride, maleic acid-acrylic acid copolymer, acrylic acid-ethyl acrylate copolymer and guar gum; the addition amount of the flocculating agent is 40mg/L, the reaction time is 2-4 hours, and the pH value is 8-10.
Secondly, performing membrane separation on the coal chemical wastewater after biochemical treatment to obtain primary treated water; the retention time of the wastewater in the membrane separation reactor is 2-24 h.
Thirdly, introducing acetic acid and ozone into the primary treated water for aeration oxidation to obtain secondary treated water; the acetic acid is industrial glacial acetic acid, the adding ratio of the mass of the acetic acid to the COD amount of raw water is 0.25-0.4: 1, the supply amount of ozone is 1-2 kg/h, and the introducing time is 1-3 h.
(IV) treating the secondary treated water by a third-stage treated water in an immobilized biological activated carbon reactor; the temperature of the water body in the immobilized biological activated carbon reactor is 21-25 ℃, and the waste water stays in the immobilized biological activated carbon reactor for 30-40 min.
And (V) filtering the third-stage treated water by a membrane to obtain purified water.
Example 1
The method comprises the following steps of taking oil refining wastewater of a certain oil refinery as raw water for advanced treatment, measuring, wherein the average COD concentration is 800mg/L, adjusting the pH value of the wastewater to be 8, adding 40mg/L of flocculant, and the flocculant comprises the following components in parts by mass: acrylamide 15; tetravinyl pentylamine 28; silicate 25; 12 parts of zinc sulfate; 0.2 percent of coagulant aid, and the balance being modified starch; silicate is aluminum silicate, coagulant aid is mixture of polymaleic anhydride and maleic acid-acrylic acid copolymer, the mixture enters the wastewater, the reaction time is 3 hours, and the COD content in the wastewater is 220mg/L after the stirring speed is 200 r/min; the wastewater enters a membrane separator, stays for 8 hours in a membrane separation reactor, active sludge and macromolecular organic matters in the wastewater after biochemical treatment are retained, primary treated water is obtained after the treatment of the membrane separation reactor, and the COD in the primary treated water is 107 mg/L; introducing acetic acid and ozone into the primary treated water for aeration oxidation to obtain secondary treated water, wherein the acetic acid is industrial glacial acetic acid, the adding ratio of the mass of the acetic acid to the COD (chemical oxygen demand) amount of the raw water is 0.3:1, the supply amount of the ozone is 1.5kg/h, and the introduction time is 2h, so that the COD content in the obtained secondary treated water is 69 mg/L; the second-stage treated water enters an immobilized biological activated carbon reactor, the temperature of the water body is 25 ℃, the retention time is 35min, and the COD content in the obtained third-stage treatment is 14 mg/L; and the third-stage treated water enters membrane filtration for filtration to obtain purified water, so that zero discharge of wastewater is realized.
Example 2
Different from the embodiment 1, the flocculating agent comprises the following components in parts by mass: acrylamide 18; tetravinyl pentylamine 30; a silicate 28; 15 parts of zinc sulfate; 0.4 percent of coagulant aid, and the balance being modified cellulose; silicate is ferric silicate, coagulant aid is the mixture of polymaleic anhydride and maleic acid-acrylic acid copolymer, and the mixture enters the wastewater, and the reaction time is 4 hours; the other structures are unchanged.
Example 3
This embodiment monitors the water before and after 30 days coal chemical industry coking wastewater advanced treatment to COD value in the water, total phenol content in the water, ammonia nitrogen content in the water monitors, and this embodiment has good advanced treatment effect to coal chemical industry coking wastewater, and aquatic COD, total phenol and ammonia nitrogen pollutant reduce more than 85%, 90% and 55% respectively.

Claims (5)

1. A coal chemical industry wastewater advanced treatment method is characterized in that: the advanced treatment method of the coal chemical industry wastewater comprises the following steps:
introducing coking wastewater subjected to common treatment into a flocculation tank and adding a flocculating agent;
secondly, performing membrane separation on the coal chemical wastewater after biochemical treatment to obtain primary treated water;
thirdly, introducing acetic acid and ozone into the primary treated water for aeration oxidation to obtain secondary treated water;
(IV) treating the secondary water in a third stage in an immobilized biological activated carbon reactor;
and (V) filtering the third-stage treated water by a membrane to obtain purified water.
2. The advanced treatment method of coal chemical industry wastewater as set forth in claim 1, characterized in that: the flocculant comprises the following components in parts by mass:
Figure FDA0001841502530000011
the balance being a matrix which is a combination of one or more of chitosan, modified starch, modified cellulose, lignin or gum;
the silicate is aluminum silicate or ferric silicate; the coagulant aid is one or a mixture of at least two of polymaleic anhydride, maleic acid-acrylic acid copolymer, acrylic acid-ethyl acrylate copolymer and guar gum.
3. The advanced treatment method of coal chemical industry wastewater as set forth in claim 1, characterized in that: the residence time in the membrane separation reactor is 2-12 h.
4. The advanced treatment method of coal chemical industry wastewater as set forth in claim 1, characterized in that: the acetic acid is industrial glacial acetic acid, and the adding ratio of the mass of the acetic acid to the COD amount of raw water is 0.25-0.4: 1.
5. The advanced treatment method of coal chemical industry wastewater as set forth in claim 1, characterized in that: the temperature of the water in the immobilized biological activated carbon reactor is 21-25 ℃.
CN201811250197.9A 2018-10-25 2018-10-25 Advanced treatment method for coal chemical industry wastewater Pending CN111099782A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114014497A (en) * 2021-11-05 2022-02-08 山东中移能节能环保科技股份有限公司 Coking wastewater treatment process

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114014497A (en) * 2021-11-05 2022-02-08 山东中移能节能环保科技股份有限公司 Coking wastewater treatment process

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Application publication date: 20200505