CN113683216A - Method for decolorizing and refining coal chemical wastewater by stripping ammonia water - Google Patents
Method for decolorizing and refining coal chemical wastewater by stripping ammonia water Download PDFInfo
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- CN113683216A CN113683216A CN202110992586.4A CN202110992586A CN113683216A CN 113683216 A CN113683216 A CN 113683216A CN 202110992586 A CN202110992586 A CN 202110992586A CN 113683216 A CN113683216 A CN 113683216A
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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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- 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
- B01D53/14—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 by absorption
- B01D53/18—Absorbing units; Liquid distributors therefor
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01C—AMMONIA; CYANOGEN; COMPOUNDS THEREOF
- C01C1/00—Ammonia; Compounds thereof
- C01C1/02—Preparation, purification or separation of ammonia
- C01C1/022—Preparation of aqueous ammonia solutions, i.e. ammonia water
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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
- C02F1/001—Processes for the treatment of water whereby the filtration technique is of importance
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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
- C02F1/28—Treatment of water, waste water, or sewage by sorption
- C02F1/283—Treatment of water, waste water, or sewage by sorption using coal, charred products, or inorganic mixtures containing them
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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
- C02F2101/30—Organic compounds
- C02F2101/34—Organic compounds containing oxygen
- C02F2101/345—Phenols
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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
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/08—Chemical Oxygen Demand [COD]; Biological Oxygen Demand [BOD]
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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
- C02F2303/00—Specific treatment goals
- C02F2303/16—Regeneration of sorbents, filters
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Abstract
The invention discloses a method for decoloring and refining coal chemical wastewater stripped ammonia water, wherein crude ammonia water obtained by wastewater stripping ammonia distillation such as coking, coal pyrolysis, coal gasification and the like usually contains phenols, so that the color is dark and the quality is influenced. The coarse ammonia water is firstly filtered by a precise filtering unit to remove suspended matters and colloid matters carried in the coarse ammonia water, and then enters an adsorption decoloring unit to remove phenols. And introducing nitrogen to blow off the residual ammonia in the adsorbent before the saturated adsorbent is regenerated, and allowing the ammonia tail gas to enter an ammonia gas absorption unit to reversely contact with the ammonia water at the outlet of the adsorption and decoloration unit to obtain refined ammonia water so as to reduce the loss of the ammonia water. The saturated adsorbent enters a regeneration unit and is introduced with alkali liquor for regeneration, the regenerated adsorbent is returned for use, and the phenol substances are recycled in the form of sodium phenolate. The total phenol content in the refined ammonia water treated by the method is less than or equal to 10ppm, and the chroma is less than or equal to 80 Haizheng. The method has stable operation, low energy consumption and simple operation and control, and can be used for decoloring and refining the stripped ammonia water of the coal chemical wastewater.
Description
Technical Field
The invention relates to a method for decoloring and refining coal chemical wastewater by stripping ammonia water, belongs to the technical field of industrial wastewater treatment, and is particularly suitable for decoloring and refining ammonia water obtained in the processes of coking, coal pyrolysis, coal gasification and the like by stripping ammonia distillation of phenol-ammonia wastewater.
Background
The phenol and ammonia nitrogen concentration in phenol-ammonia wastewater of coking, coal pyrolysis, coal gasification and the like is high, the ammonia water obtained through the steam stripping and ammonia distillation process often contains phenol organic matters with certain concentration, the concentration is sometimes as high as thousands or even tens of thousands mg/L, phenols can be oxidized into red quinone substances, the COD (chemical oxygen demand) of the ammonia water is high, the color is deep, the quality of the ammonia water is poor, and the recycling is influenced. Meanwhile, the phenol substance has higher purity and has recovery value. The removal method of the phenolic substances comprises an advanced oxidation method, a solvent extraction method, an adsorption method and the like, wherein the advanced oxidation method such as an ozone oxidation method has a good effect of removing the phenolic organic substances, but the cost is high, and the organic substances cannot be recycled by oxidative degradation. Both solvent extraction and adsorption methods can effectively recover phenolic substances, and how to avoid ammonia water loss during the recovery of the phenolic substances needs to be considered.
Disclosure of Invention
The invention aims to provide a method for decoloring and refining coal chemical wastewater by stripping ammonia water, which can be used for refining crude ammonia water and simultaneously recycling phenols.
A method for decoloring and refining coal chemical wastewater by stripping ammonia water is characterized by comprising the following steps:
(1) coarse ammonia water obtained by steam stripping of coal chemical wastewater passes through a precise filtering unit to remove suspended matters and colloid substances carried by the coarse ammonia water;
(2) the ammonia water after the precision filtration enters an adsorption and decoloration unit, phenols are removed by adopting an adsorbent, and the ammonia water after the adsorption enters an ammonia gas absorption unit from an outlet of the adsorption and decoloration unit;
(3) after the adsorbent in the step (2) is saturated, introducing nitrogen to blow off ammonia remaining in the adsorbent before regeneration; the ammonia tail gas after stripping enters an ammonia gas absorption unit and is in reverse contact with the ammonia water flowing out of the outlet of the adsorption and decoloration unit to obtain refined ammonia water;
(4) and (4) allowing the saturated adsorbent blown off in the step (3) to enter a regeneration unit, adopting alkali liquor as a regeneration medicament, returning the regenerated adsorbent to use, and recovering the phenol substances in a sodium phenolate form.
Further, the concentration of the crude ammonia water in the step (1) is 8% to 25%, for example, the concentration of the ammonia water may be 10%, 15%, or 20%.
Further, the concentration of phenols in the crude ammonia water in the step (1) is 1000-10000 mg/L in terms of total phenols, for example, the concentration of phenols can be 2000mg/L, 4000mg/L, 6000mg/L, 8000mg/L and 10000 mg/L.
Furthermore, the precision filtration unit in the step (1) has a filtration precision of 5-100 μm, for example, the precision filtration unit may have a filtration precision of 5 μm, 10 μm, 20 μm, 50 μm, 100 μm.
Further, the adsorbent in the step (2) is granular activated carbon or activated carbon fiber.
Furthermore, the adsorption decoloring unit comprises N adsorption tanks, wherein any M adsorption tanks can realize series operation, and at least one adsorption tank is regenerated or reserved; m is more than or equal to 2 and less than N, and M, N are all natural numbers.
Furthermore, the purity of the nitrogen introduced in the step (3) is more than 99%.
Further, in the step (4), the regeneration agent is NaOH solution, the concentration is 1% -10%, and the regeneration temperature is 30-90 ℃. For example, the concentration of the alkali solution may be 2%, 4%, 6%, 8%, and the regeneration temperature may be 40 ℃, 60 ℃, 80 ℃, 90 ℃.
Further, the concentration of total phenols in the refined ammonia water obtained in the step (3) is less than or equal to 10mg/L, and the chroma is less than or equal to 80 Haizheng.
The principle of the invention is as follows: suspended matters and colloid substances carried in the crude ammonia are removed through precise filtration, phenol organic matters in the crude ammonia are adsorbed and removed through activated carbon, and the phenol-containing saturated activated carbon firstly blows off residual ammonia on the surface of an adsorbent through nitrogen and enters an ammonia absorption unit for absorption, so that the concentration loss of ammonia water is reduced. The saturated activated carbon is regenerated and reused under the condition of alkali liquor, and the phenolic substances are recovered in the form of sodium phenolate. The invention has the following beneficial effects: the whole process is simple and convenient to operate, the energy consumption is low, the adsorbent can be recycled, the phenolic substances are recovered, and the ammonia concentration loss is low.
Drawings
FIG. 1 is a process flow diagram of the present invention.
Detailed Description
The technical scheme of the invention is clearly and completely described below by combining the attached drawings of the specification. It is to be understood that the described embodiments are merely exemplary of some, and not necessarily all, embodiments of the invention. All other embodiments, which can be obtained by a person skilled in the art without making creative efforts based on the embodiments of the present invention, belong to the protection scope of the present invention.
Example 1
Carrying out steam stripping on the coal chemical industry wastewater to distill ammonia to obtain crude ammonia water, wherein the ammonia concentration is 10 percent, and the ammonia water contains 5000mg/L of total phenol, firstly removing suspended matters and colloid matters through a precision filter, and the precision of the filter is 5 mu m; then the mixture enters an adsorption and decoloration unit, and phenol substances are adsorbed and removed by adopting a granular activated carbon adsorption tank at normal temperature and normal pressure; introducing nitrogen (with purity of 99%) before the saturated adsorbent is regenerated to blow off residual ammonia in the adsorbent, and allowing ammonia tail gas to enter an ammonia gas absorption unit and reversely contact ammonia water at an outlet of an adsorption and decoloration unit to obtain refined ammonia water, wherein the total phenol concentration is 5mg/L, and the chroma is 50 Hazen; the saturated adsorbent enters a regeneration unit, 4% NaOH alkali liquor is adopted to regenerate the adsorbent at the temperature of 60 ℃, the regenerated adsorbent is returned for use, and the phenol substances are recovered in the form of sodium phenolate.
Example 2
Carrying out steam stripping on the coal chemical industry wastewater to distill ammonia to obtain crude ammonia water, wherein the ammonia concentration is 22 percent, and the crude ammonia water contains 6000mg/L of total phenols, and firstly removing suspended matters and colloid matters through a precision filter, wherein the precision of the filter is 10 mu m; then enters an adsorption and decoloration unit, and phenol substances are adsorbed and removed by adopting an activated carbon fiber adsorption tank at normal temperature and normal pressure; introducing nitrogen (with purity of 99.9%) before the saturated adsorbent is regenerated to blow off ammonia remaining in the adsorbent, and allowing ammonia tail gas to enter an ammonia gas absorption unit and reversely contact ammonia water at an outlet of an adsorption and decoloration unit to obtain refined ammonia water, wherein the total phenol concentration is 8mg/L, and the chroma is 70 Hazen; the saturated adsorbent enters a regeneration unit, 6% NaOH alkali liquor is adopted to regenerate the adsorbent at the temperature of 80 ℃, the regenerated adsorbent is returned for use, and the phenol substances are recovered in a sodium phenolate form.
Example 3
Carrying out steam stripping on the coal chemical industry wastewater to distill ammonia to obtain crude ammonia water, wherein the ammonia concentration is 15 percent, and the crude ammonia water contains 3000mg/L of total phenols, firstly removing suspended matters and colloid matters through a precision filter, and the precision of the filter is 50 mu m; then enters an adsorption and decoloration unit, and phenol substances are adsorbed and removed by adopting an activated carbon fiber adsorption tank at normal temperature and normal pressure; introducing nitrogen (with purity of 99.9%) before the saturated adsorbent is regenerated to blow off ammonia remaining in the adsorbent, and allowing ammonia tail gas to enter an ammonia gas absorption unit and reversely contact ammonia water at an outlet of an adsorption and decoloration unit to obtain refined ammonia water, wherein the total phenol concentration is 2mg/L, and the chroma is 50 Hazen; the saturated adsorbent enters a regeneration unit, 5% NaOH alkali liquor is adopted to regenerate the adsorbent at the temperature of 60 ℃, the regenerated adsorbent is returned for use, and the phenol substances are recovered in the form of sodium phenolate.
Example 4
Carrying out steam stripping on the coal chemical wastewater to distill ammonia to obtain crude ammonia water, wherein the ammonia concentration is 25 percent, and the crude ammonia water contains 7000mg/L of total phenols, firstly removing suspended matters and colloid matters through a precision filter, and the precision of the filter is 100 mu m; then the mixture enters an adsorption and decoloration unit, and phenol substances are adsorbed and removed by adopting a granular activated carbon adsorption tank at normal temperature and normal pressure; introducing nitrogen (with purity of 99%) before the saturated adsorbent is regenerated to blow off residual ammonia in the adsorbent, and allowing ammonia tail gas to enter an ammonia gas absorption unit and reversely contact ammonia water at an outlet of an adsorption and decoloration unit to obtain refined ammonia water, wherein the total phenol concentration is 10mg/L, and the chroma is 80 Hazen; the saturated adsorbent enters a regeneration unit, the adsorbent is regenerated by adopting 3% NaOH alkali liquor at the temperature of 70 ℃, the regenerated adsorbent is returned for use, and the phenol substances are recovered in a sodium phenolate form.
Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made in the above embodiments by those of ordinary skill in the art without departing from the principle and spirit of the present invention. The scope of the invention is defined by the claims and their equivalents.
Claims (9)
1. A method for decoloring and refining coal chemical wastewater by stripping ammonia water is characterized by comprising the following steps:
(1) coarse ammonia water obtained by steam stripping of coal chemical wastewater passes through a precise filtering unit to remove suspended matters and colloid substances carried by the coarse ammonia water;
(2) the ammonia water after the precision filtration enters an adsorption and decoloration unit, phenols are removed by adopting an adsorbent, and the ammonia water after the adsorption enters an ammonia gas absorption unit from an outlet of the adsorption and decoloration unit;
(3) after the adsorbent in the step (2) is saturated, introducing nitrogen to blow off ammonia remaining in the adsorbent before regeneration; the ammonia tail gas after stripping enters an ammonia gas absorption unit and is in reverse contact with the ammonia water flowing out of the outlet of the adsorption and decoloration unit to obtain refined ammonia water;
(4) and (4) allowing the saturated adsorbent blown off in the step (3) to enter a regeneration unit, adopting alkali liquor as a regeneration medicament, returning the regenerated adsorbent to use, and recovering the phenol substances in a sodium phenolate form.
2. The method according to claim 1, wherein the concentration of the crude ammonia water in the step (1) is 8 to 25%.
3. The method according to claim 1, wherein the concentration of the phenolic substances in the crude ammonia water in the step (1) is 1000-10000 mg/L in terms of total phenols.
4. The method according to claim 1, wherein the precision filtration unit in the step (1) has a filtration precision of 5-100 μm.
5. The method of claim 1, wherein the adsorbent in step (2) is granular activated carbon or activated carbon fiber.
6. The method of claim 1, wherein the adsorption decoloring unit comprises N adsorption tanks, wherein any M adsorption tanks can be operated in series, and at least one adsorption tank is regenerated or standby; m is more than or equal to 2 and less than N, and M, N are all natural numbers.
7. The method according to claim 1, wherein the purity of the nitrogen introduced in the step (3) is 99% or more.
8. The method according to claim 1, wherein the regeneration agent in the step (4) is NaOH solution, the concentration is 1-10%, and the regeneration temperature is 30-90 ℃.
9. The process according to claim 1, wherein the purified aqueous ammonia obtained in the step (3) has a total phenol concentration of 10mg/L or less and a hue of 80 Hazen or less.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115738587A (en) * | 2022-12-02 | 2023-03-07 | 珠海格力电器股份有限公司 | Waste material removes ammonia system |
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| FR2882761B1 (en) * | 2005-03-04 | 2007-08-31 | Inst Francais Du Petrole | PROCESS FOR THE DESULFURATION AND / OR DEAZOTATION OF A HYDROCARBONATED LOAD BY OXYDESULFURATION |
| CN206188534U (en) * | 2016-11-09 | 2017-05-24 | 南京大学 | Phenol ammonia wastewater deamination and ammonia purification system |
| CN109384341A (en) * | 2018-11-30 | 2019-02-26 | 西安百特瑞化工工程有限公司 | Semi-coke high concentrated organic wastewater recycling treatment system and method |
| CN110498564A (en) * | 2019-08-20 | 2019-11-26 | 石家庄惠洁科技有限公司 | A kind of coking, semi-coke wastewater low-cost high-efficiency treatment process |
| CN112121779A (en) * | 2019-06-25 | 2020-12-25 | 内蒙古伊泰煤基新材料研究院有限公司 | Method and apparatus for regenerating adsorbent for removing oxide in FT synthetic oil |
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- 2021-08-27 CN CN202110992586.4A patent/CN113683216B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2882761B1 (en) * | 2005-03-04 | 2007-08-31 | Inst Francais Du Petrole | PROCESS FOR THE DESULFURATION AND / OR DEAZOTATION OF A HYDROCARBONATED LOAD BY OXYDESULFURATION |
| CN206188534U (en) * | 2016-11-09 | 2017-05-24 | 南京大学 | Phenol ammonia wastewater deamination and ammonia purification system |
| CN109384341A (en) * | 2018-11-30 | 2019-02-26 | 西安百特瑞化工工程有限公司 | Semi-coke high concentrated organic wastewater recycling treatment system and method |
| CN112121779A (en) * | 2019-06-25 | 2020-12-25 | 内蒙古伊泰煤基新材料研究院有限公司 | Method and apparatus for regenerating adsorbent for removing oxide in FT synthetic oil |
| CN110498564A (en) * | 2019-08-20 | 2019-11-26 | 石家庄惠洁科技有限公司 | A kind of coking, semi-coke wastewater low-cost high-efficiency treatment process |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115738587A (en) * | 2022-12-02 | 2023-03-07 | 珠海格力电器股份有限公司 | Waste material removes ammonia system |
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