CN110510776B - Heavy metal sewage treatment method - Google Patents
Heavy metal sewage treatment method Download PDFInfo
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- CN110510776B CN110510776B CN201910834188.2A CN201910834188A CN110510776B CN 110510776 B CN110510776 B CN 110510776B CN 201910834188 A CN201910834188 A CN 201910834188A CN 110510776 B CN110510776 B CN 110510776B
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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
- C02F1/5245—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using inorganic agents using basic salts, e.g. of aluminium and iron
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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
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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
- C02F1/66—Treatment of water, waste water, or sewage by neutralisation; pH adjustment
-
- 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
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- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Removal Of Specific Substances (AREA)
Abstract
The invention discloses a heavy metal sewage treatment method, which comprises the following steps: (1) adding sodium sulfide into the sewage, and heating and preserving heat; (2) adding ferrous sulfate, dimethyl diallyl ammonium chloride and sodium dodecyl sulfate into the sewage, and stirring at high temperature to obtain a mixed solution; (3) cooling the mixed solution, and adding sodium hydroxide while cooling; (4) and (3) filtering, stirring the mixed solution in a magnetic field, adding sodium persulfate, filtering again, and adding an acidic solution into the mixed solution for neutralization. The sewage treated by the sodium sulfide is treated by ferrous sulfate, dimethyl diallyl ammonium chloride and sodium dodecyl sulfate, so that the removal effect of heavy metals can be improved; sodium hydroxide is added in the cooling process, and the ratio of heavy metal in the sewage converted into sediment can be improved by matching with magnetic field.
Description
Technical Field
The invention relates to the technical field of sewage treatment, in particular to a heavy metal sewage treatment method.
Background
The heavy metal wastewater is mainly from wastewater discharged by enterprises such as mines, smelting, electrolysis, electroplating, pesticides, medicines, paints, pigments and the like.
In industrial production, in order to reduce environmental pollution, sewage is purified and then discharged, and one important link of purifying the sewage is to remove heavy metals in the sewage. At present, the treatment of heavy metal sewage includes chemical treatment, physical treatment and biological treatment, and the chemical treatment mostly adjusts the PH of sewage and uses sulfur ions to precipitate heavy metals in sewage, thereby achieving the effect of removing heavy metals.
The existing chemical treatment method for sewage simply depends on chemical substances, the conversion rate of chemical reaction depends on reaction environment to a certain extent, and the removal effect is not ideal due to the fact that the chemical substances are simply added.
Disclosure of Invention
The invention aims to provide a heavy metal sewage treatment method with better heavy metal removal effect.
A heavy metal sewage treatment method comprises the following steps:
(1) adding sodium sulfide into the sewage, and heating and preserving heat;
(2) adding ferrous sulfate, dimethyl diallyl ammonium chloride and sodium dodecyl sulfate into the sewage, and stirring at high temperature to obtain a mixed solution;
(3) cooling the mixed solution, and adding sodium hydroxide while cooling;
(4) and (3) filtering, stirring the mixed solution in a magnetic field, adding sodium persulfate, filtering again, and adding an acidic solution into the mixed solution for neutralization.
The invention has the beneficial effects that: the sewage treated by the sodium sulfide is treated by ferrous sulfate, dimethyl diallyl ammonium chloride and sodium dodecyl sulfate, so that the removal effect of heavy metals can be improved; sodium hydroxide is added in the cooling process, and the ratio of heavy metal in the sewage converted into sediment can be improved by matching with magnetic field.
In addition, the heavy metal sewage treatment method provided by the invention can also have the following additional technical characteristics:
further, in the step (1), the concentration of the sodium sulfide is 200-600 mg/L, and the adding amount is 1-2% of the weight of the sewage.
Further, the heating and heat preservation temperature is 50-60 ℃, and the duration time is 3-5 hours.
Further, in the step (2), the concentrations of the ferrous sulfate, the dimethyl diallyl ammonium chloride and the sodium dodecyl sulfate are respectively 50-100 mg/L, 10-20 mg/L and 50-80 mg/L, and the adding amounts of the ferrous sulfate, the dimethyl diallyl ammonium chloride and the sodium dodecyl sulfate are respectively 1-2%, 2-5% and 0.2-1% of the weight of the sewage.
Further, the high-temperature stirring temperature is 80-90 ℃.
Further, in the step (3), the temperature is reduced to 5 ℃ within the range of 0.1-0.3 ℃/min.
Further, the concentration of the sodium hydroxide is 50-150 mg/L, and the adding amount is controlled until the pH of the sewage is = 10.
Further, in the step (4), the average magnetic field intensity of the magnetic field is 0.2-0.7T, and the holding time is 1-2 hours.
Further, in the step (4), the concentration of the sodium persulfate is 10-20 mg/L, the adding amount is 0.5-1% of the weight of the sewage, and the acid solution is one or a combination of hydrochloric acid, ammonium chloride and carbonic acid.
Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
Detailed Description
In order to make the objects, features and advantages of the present invention comprehensible, specific embodiments accompanied with examples are described in detail below. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.
Example 1
A heavy metal sewage treatment method comprises the following steps:
(1) adding sodium sulfide into the sewage, and heating and preserving heat, wherein the concentration of the sodium sulfide is 550mg/L, the adding amount of the sodium sulfide is 1.5 percent of the weight of the sewage, the heating and preserving heat temperature is 50 ℃, and the duration time is 3 hours;
(2) adding ferrous sulfate, dimethyl diallyl ammonium chloride and lauryl sodium sulfate into the sewage, and stirring at a high temperature, wherein the concentrations of the ferrous sulfate, the dimethyl diallyl ammonium chloride and the lauryl sodium sulfate are respectively 70mg/L, 20mg/L and 60mg/L, the addition amounts of the ferrous sulfate, the dimethyl diallyl ammonium chloride and the lauryl sodium sulfate are respectively 1%, 3% and 0.6% of the weight of the sewage, and the temperature of the high-temperature stirring is 90 ℃ to obtain a mixed solution;
(3) cooling the mixed solution, and adding sodium hydroxide while cooling, wherein the cooling amplitude of the cooling is 0.1 ℃/min, the cooling is carried out until the temperature is reduced to 5 ℃, the concentration of the sodium hydroxide is 90mg/L, and the adding amount is that the pH of the sewage is = 10;
(4) and (2) filtering, stirring the mixed solution under a magnetic field, adding sodium persulfate, wherein the average magnetic field intensity of the magnetic field is 0.6T, the holding time is 1 hour, filtering again, and adding an acidic solution into the mixed solution for neutralization, wherein the concentration of the sodium persulfate is 10mg/L, the adding amount is 0.7 percent of the weight of the sewage, and the acidic solution is hydrochloric acid, and the neutralization is carried out until the pH is = 7.
In treating sewage, the sewage may be injected into a treatment tank, and a magnetic field is applied to both sides of the treatment tank.
The method has the advantages that the sewage treated by the sodium sulfide is treated by ferrous sulfate, dimethyl diallyl ammonium chloride and sodium dodecyl sulfate, so that the removal effect of heavy metals can be improved; sodium hydroxide is added in the cooling process, and the ratio of heavy metal in the sewage converted into sediment can be improved by matching with magnetic field.
Example 2
A heavy metal sewage treatment method comprises the following steps:
(1) adding sodium sulfide into the sewage, and heating and preserving heat, wherein the concentration of the sodium sulfide is 200mg/L, the adding amount of the sodium sulfide is 1% of the weight of the sewage, the heating and preserving heat temperature is 50 ℃, and the duration time is 3 hours;
(2) adding ferrous sulfate, dimethyl diallyl ammonium chloride and sodium dodecyl sulfate into the sewage, and stirring at a high temperature, wherein the concentrations of the ferrous sulfate, the dimethyl diallyl ammonium chloride and the sodium dodecyl sulfate are respectively 50mg/L, 10mg/L and 50mg/L, the addition amounts of the ferrous sulfate, the dimethyl diallyl ammonium chloride and the sodium dodecyl sulfate are respectively 1%, 2% and 0.2% of the weight of the sewage, and the temperature of the high-temperature stirring is 80 ℃ to obtain a mixed solution;
(3) cooling the mixed solution, and adding sodium hydroxide while cooling, wherein the cooling amplitude of the cooling is 0.1 ℃/min, the cooling is carried out until the temperature is reduced to 5 ℃, the concentration of the sodium hydroxide is 50mg/L, and the adding amount is that the pH of the sewage is = 10;
(4) and (2) filtering, stirring the mixed solution under a magnetic field, adding sodium persulfate, adding an acidic solution into the mixed solution for neutralization, wherein the average magnetic field intensity of the magnetic field is 0.2T, the retention time is 1 hour, filtering again, and adding the acidic solution into the mixed solution for neutralization, the concentration of the sodium persulfate is 10mg/L, the addition amount of the sodium persulfate is 0.5 percent of the weight of the sewage, the acidic solution is a combination of ammonium chloride and carbonic acid, and the neutralization is carried out until the pH is = 7.
Example 3
A heavy metal sewage treatment method comprises the following steps:
(1) adding sodium sulfide into the sewage, and heating and preserving heat, wherein the concentration of the sodium sulfide is 600mg/L, the adding amount of the sodium sulfide is 2% of the weight of the sewage, the heating and preserving heat temperature is 60 ℃, and the duration time is 5 hours;
(2) adding ferrous sulfate, dimethyl diallyl ammonium chloride and sodium dodecyl sulfate into the sewage, and stirring at a high temperature, wherein the concentrations of the ferrous sulfate, the dimethyl diallyl ammonium chloride and the sodium dodecyl sulfate are respectively 100mg/L, 20mg/L and 80mg/L, the addition amounts of the ferrous sulfate, the dimethyl diallyl ammonium chloride and the sodium dodecyl sulfate are respectively 2%, 5% and 1% of the weight of the sewage, and the temperature of the high-temperature stirring is 90 ℃ to obtain a mixed solution;
(3) cooling the mixed solution, and adding sodium hydroxide while cooling, wherein the cooling amplitude of the cooling is 0.3 ℃/min, the cooling is carried out until the temperature is reduced to 5 ℃, the concentration of the sodium hydroxide is 150mg/L, and the adding amount is that the pH of the sewage is = 10;
(4) and filtering, stirring the mixed solution under a magnetic field, adding sodium persulfate, wherein the average magnetic field intensity of the magnetic field is 0.7T, the holding time is 2 hours, filtering again, and adding an acidic solution into the mixed solution for neutralization, wherein the concentration of the sodium persulfate is 20mg/L, the adding amount is 1% of the weight of the sewage, and the acidic solution is one or a combination of more of hydrochloric acid, sodium carbonate and sodium bicarbonate.
Comparative example 1
A heavy metal sewage treatment method comprises the following steps:
adding sodium sulfide into the sewage, heating and preserving heat, wherein the concentration of the sodium sulfide is 550mg/L, the adding amount of the sodium sulfide is 1.5 percent of the weight of the sewage, the temperature of the heating and preserving heat is 50 ℃, and the duration time is 3 hours.
Comparative example 2
A heavy metal sewage treatment method comprises the following steps:
(1) adding sodium sulfide into the sewage, and heating and preserving heat, wherein the concentration of the sodium sulfide is 550mg/L, the adding amount of the sodium sulfide is 1.5 percent of the weight of the sewage, the heating and preserving heat temperature is 50 ℃, and the duration time is 3 hours;
(2) and adding ferrous sulfate into the sewage, and stirring at high temperature, wherein the concentration of the ferrous sulfate is 70mg/L, the adding amount is 1 percent of the weight of the sewage, and the temperature of the high-temperature stirring is 90 ℃.
Comparative example 3
This comparative example is substantially the same as example 1 except that the step (3) is:
and cooling the mixed solution, and adding sodium hydroxide at the temperature of 20 ℃, wherein the concentration of the sodium hydroxide is 90mg/L, and the adding amount is that the pH of the sewage is = 10.
Comparative example 4
This comparative example is substantially the same as example 1 except that the mixed solution was not subjected to a magnetic field in step (4).
The invention adopts the sewage of a certain mine field in the Jiangxi province for verification, the initial concentration of heavy metal is 240mg/L of iron, 710mg/L of copper, 8.5mg/L of lead and 2.3mg/L of cadmium, the sewage is respectively treated by adopting the embodiment and the comparison example, the content of various metals in the treated sewage is measured by adopting a graphite furnace atomic absorption spectrophotometry, the removal rate is calculated, and the result is shown in a table 1.
TABLE 1
| Grouping | Iron (mg/L) | Iron removal Rate (%) | Copper (mg/L) | Copper removal (%) | Lead (mg/L) | Lead removal (%) | Cadmium (mg/L) | Cadmium removal Rate (%) |
| Initial sewage | 240 | - | 710 | - | 8.5 | - | 2.3 | - |
| Example 1 | 8 | 96.7 | 27 | 96.2 | 0.3 | 96.5 | 0.05 | 97.8 |
| Example 2 | 13 | 96.6 | 22 | 96.9 | 0.3 | 96.5 | 0.07 | 96.9 |
| Example 3 | 18 | 92.5 | 36 | 94.9 | 0.4 | 95.3 | 0.04 | 98.3 |
| Comparative example 1 | 66 | 72.5 | 83 | 88.3 | 2.5 | 70.6 | 0.21 | 90.9 |
| Comparative example 2 | 42 | 82.5 | 64 | 91.0 | 1.6 | 81.2 | 0.14 | 93.9 |
| Comparative example 3 | 21 | 91.3 | 44 | 93.8 | 1.1 | 87.1 | 0.08 | 96.5 |
| Comparative example 4 | 28 | 88.3 | 52 | 92.7 | 0.6 | 92.9 | 0.07 | 96.9 |
As can be seen from table 1, examples 1, 2 and 3 all achieved good removal effects, and the removal rates all reached more than 96%; comparing example 1, comparative example 1 and comparative example 2, it can be seen that example 1 has a distinct advantage over comparative example 1 and comparative example 2; comparing example 1, comparative example 3 and comparative example 4, it can be seen that the addition of sodium hydroxide and the use of a magnetic field at a reduced temperature can promote the removal of heavy metals to some extent.
In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (7)
1. The heavy metal sewage treatment method is characterized by comprising the following steps:
(1) adding sodium sulfide into the sewage, and heating and preserving heat;
(2) adding ferrous sulfate, dimethyl diallyl ammonium chloride and sodium dodecyl sulfate into the sewage, and stirring at a high temperature to obtain a mixed solution, wherein the high-temperature stirring temperature is 80-90 ℃;
(3) cooling the mixed solution, adding sodium hydroxide while cooling, wherein the cooling amplitude of the cooling is 0.1-0.3 ℃/min, and cooling to 5 ℃;
(4) and (3) filtering, stirring the mixed solution in a magnetic field, adding sodium persulfate, filtering again, and adding an acidic solution into the mixed solution for neutralization.
2. The heavy metal sewage treatment method according to claim 1, wherein in the step (1), the concentration of the sodium sulfide is 200-600 mg/L, and the addition amount of the sodium sulfide is 1-2% of the weight of the sewage.
3. The heavy metal sewage treatment method according to claim 1 or 2, wherein the heating and heat preservation temperature is 50-60 ℃ and the duration is 3-5 hours.
4. The heavy metal sewage treatment method according to claim 1, wherein in the step (2), the concentrations of the ferrous sulfate, the dimethyl diallyl ammonium chloride and the sodium dodecyl sulfate are respectively 50-100 mg/L, 10-20 mg/L and 50-80 mg/L, and the addition amounts of the ferrous sulfate, the dimethyl diallyl ammonium chloride and the sodium dodecyl sulfate are respectively 1-2%, 2-5% and 0.2-1% of the weight of the sewage.
5. The heavy metal wastewater treatment method according to claim 1, wherein the concentration of the sodium hydroxide is 50 to 150mg/L, and the sodium hydroxide is added until the pH of the wastewater is = 10.
6. The heavy metal wastewater treatment method according to claim 1, wherein in the step (4), the average magnetic field strength of the magnetic field is 0.2-0.7T, and the retention time is 1-2 hours.
7. The heavy metal wastewater treatment method according to claim 1 or 6, wherein in the step (4), the concentration of the sodium persulfate is 10-20 mg/L, the addition amount is 0.5-1% of the wastewater weight, and the acidic solution is one or more of hydrochloric acid, ammonium chloride and carbonic acid.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101186373A (en) * | 2007-11-30 | 2008-05-28 | 华南理工大学 | Method for processing paroxysmal mercury polluted water under emergency condition |
| CN102010084A (en) * | 2010-11-09 | 2011-04-13 | 中国兵器工业集团第五三研究所 | Treatment method of copper-bearing waste water |
| CN102531280A (en) * | 2011-12-16 | 2012-07-04 | 深圳市祐林环保有限公司 | Method for treating wastewater of printed circuit board |
| WO2014153965A1 (en) * | 2013-03-28 | 2014-10-02 | 南京大学宜兴环保研究院 | Composite flocculating agent and method for processing radioactive elements iron, cobalt, manganese and silver in nuclear wastewater |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101186373A (en) * | 2007-11-30 | 2008-05-28 | 华南理工大学 | Method for processing paroxysmal mercury polluted water under emergency condition |
| CN102010084A (en) * | 2010-11-09 | 2011-04-13 | 中国兵器工业集团第五三研究所 | Treatment method of copper-bearing waste water |
| CN102531280A (en) * | 2011-12-16 | 2012-07-04 | 深圳市祐林环保有限公司 | Method for treating wastewater of printed circuit board |
| WO2014153965A1 (en) * | 2013-03-28 | 2014-10-02 | 南京大学宜兴环保研究院 | Composite flocculating agent and method for processing radioactive elements iron, cobalt, manganese and silver in nuclear wastewater |
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