CN110272111A - A kind of oxidant and preparation method thereof removing high-salt wastewater COD organic matter - Google Patents
A kind of oxidant and preparation method thereof removing high-salt wastewater COD organic matter Download PDFInfo
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- CN110272111A CN110272111A CN201910703611.5A CN201910703611A CN110272111A CN 110272111 A CN110272111 A CN 110272111A CN 201910703611 A CN201910703611 A CN 201910703611A CN 110272111 A CN110272111 A CN 110272111A
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- oxidant
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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
- C02F1/72—Treatment of water, waste water, or sewage by oxidation
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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
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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)
- Treatment Of Water By Oxidation Or Reduction (AREA)
Abstract
The present invention disclose it is a kind of remove high-salt wastewater COD organic matter oxidant and preparation method thereof, compounded by the raw material of following weight percent: sodium nitrite 12-15%, sodium peroxydisulfate 17-21%, Zero-valent Iron 5-10%, sodium sulfite 12-17%, ferrous sulfate 5-8%, remaining be water.Preparation method comprises the steps of: (1) configuration of component A: being sequentially added in water by sodium nitrite, sodium peroxydisulfate, sulfuric acid, is stirred evenly under room temperature, is filled in storage vat and saves；(2) configuration of component B: Zero-valent Iron, sodium sulfite, ferrous sulfate are mixed, is stirred evenly under room temperature, is filled in storage vat and saves；(3) compounding mixing: component A, component B are mixed in proportion, obtain oxidant after mixing evenly.Compared with the existing technology, formula of the invention so that Zero-valent Iron and ferrous sulfate it is common activate under produce the extremely strong potentiometric titrations of oxidation activity, can effectively remove the COD organic matter in high-salt wastewater, removal efficiency is up to 84%.
Description
Technical field
The invention belongs to water-treatment technology fields, and in particular to it is a kind of remove high-salt wastewater COD organic matter oxidant and
Preparation method.
Background technique
The waste water overwhelming majority generated in industrial production all organic matter containing high concentration and salt amount are especially returned in middle water
High-salt wastewater COD organic matter can be generated in the process with wastewater zero discharge, processing difficulty is big.Amount with high salt limits life in waste water
Object processing, is that cost for wastewater treatment increases very much.With the continuous improvement to environmental requirement, the place of high-salt wastewater COD organic matter
Reason becomes the problem in the urgent need to address of many enterprises.
The processing method of existing high-salt wastewater COD organic matter mainly has the skills such as biological treatment, embrane method, advanced oxidation processes
Art.
Biological treatment is after being diluted waste water, and addition nutrition carries out biological treatment；The technology can effectively degrade useless
Organic substance in water, removal efficiency is higher, but there is a problem of taking up a large area, invests that operating cost is high, limits the engineering of technology
Using.COD waste water with high salt is handled with embrane method, has occupied area small, the low feature of operation investment cost, but that there are flux is small,
Easily dirty block up is not easy to restore, cannot remove small molecule COD problem.Advanced oxidation processes are to utilize strong oxidizer by organic contamination in waste water
Object direct oxidation is nontoxic small-molecule substance even CO2And H2O；The technology removal efficiency is high, and simple process is easy to operate, but exists
The problems such as cost is relatively high, and processing is not thorough.
Above-mentioned high-salt wastewater COD method for treating organic material has respective limitation, and there are organic matter degradations to be not thorough
The problems such as.Therefore, a kind of more simple and effective oxidant is developed, to the processing of high-salt wastewater COD organic matter and environment is promoted to protect
Protector is significant.
Summary of the invention
In order to solve the problems, such as that above-mentioned high-salt wastewater COD organic matter degradation of the existing technology is halfway, the present invention is mentioned
For a kind of oxidant and preparation method thereof for removing high-salt wastewater COD organic matter.
To achieve the above object, the present invention uses following reagent combination:
A kind of oxidant removing high-salt wastewater COD organic matter, is compounded: sodium nitrite by the raw material of following weight percent
12-15%, sodium peroxydisulfate 17-21%, Zero-valent Iron 5-10%, sodium sulfite 12-17%, ferrous sulfate 5-8%, remaining be water.
The preparation method of the oxidant of the removal high-salt wastewater COD organic matter, comprises the steps of:
(1) configuration of component A: being sequentially added in water by sodium nitrite, sodium peroxydisulfate, sulfuric acid, is stirred evenly, is filled under room temperature
It is saved in storage vat；
(2) configuration of component B: Zero-valent Iron, sodium sulfite, ferrous sulfate are mixed, is stirred evenly under room temperature, is filled to storage vat
Middle preservation；
(3) compounding mixing: component A, component B are mixed in proportion, obtain oxidant after mixing evenly.
After high-salt wastewater is added when the oxidant uses, adjusting its pH value of solution is 4-6.
Component A in the step (3), component B mixed weight ratio be 1:(0.5-2).
Compared with the existing technology, formula of the invention is so that produce oxygen under the common activation of Zero-valent Iron and ferrous sulfate
Change the extremely strong potentiometric titrations of activity, can effectively remove the COD organic matter in high-salt wastewater, removal efficiency is up to 84%.
Specific embodiment
A kind of oxidant removing high-salt wastewater COD organic matter, is compounded: nitrous by the raw material of following weight percent
Sour sodium 12-15%, sodium peroxydisulfate 17-21%, Zero-valent Iron 5-10%, sodium sulfite 12-17%, ferrous sulfate 5-8%, remaining be water.
The present invention also provides the preparation methods of the oxidant of the removal high-salt wastewater COD organic matter described in one kind, by following
Step composition:
(1) configuration of component A: being sequentially added in water by sodium nitrite, sodium peroxydisulfate, sulfuric acid, is stirred evenly, is filled under room temperature
It is saved in storage vat；
(2) configuration of component B: Zero-valent Iron, sodium sulfite, ferrous sulfate are mixed, is stirred evenly under room temperature, is filled to storage vat
Middle preservation；
(3) compounding mixing: component A, component B are mixed in proportion, obtain oxidant after mixing evenly.
Further, after high-salt wastewater is added when the oxidant uses, adjusting its pH value of solution is 4-6.
Further, component A in the step (3), component B mixed weight ratio be 1:(0.5-2).
Oxidant is added in high-salt wastewater COD organic matter reaction tank using metering pump when use.
For the invention will be further described, it is described in detail below in conjunction with specific embodiment.Following embodiments
Middle raw material assembly is 100g.
Embodiment 1
The configuration for carrying out component A first, sequentially adds suitable quantity of water by weight sodium nitrite 13%, sodium peroxydisulfate 20% in proportion
In, it is stirred evenly under room temperature, is filled in the plastic barrel of 25L volume and saves.
Then the configuration for carrying out component B, it is mixed by weight the ratio of Zero-valent Iron 8%, sodium sulfite 15%, ferrous sulfate 6%
It closes, is stirred evenly under room temperature, be encapsulated into the plastic barrel of 25L volume and save.
In use, two kinds of components A, B are mixed by weight the ratio of 1:1, oxidant can be used as after mixing evenly.It uses
When can be used metering pump oxidant is added in high-salt wastewater COD organic matter reaction tank.
By oxidant obtained in embodiment 1, taking this oxidant of 250ml is experimental subjects, is added to the high-salt wastewater of 1L
Water sample in, wherein COD concentration be 1200mg/l, TDS range 8000mg/l, with 10% glacial acetic acid adjust solution pH value be 5,
It is reacted under the conditions of 45 DEG C, after 3 hours, measuring COD removal efficiency is 84%.
Embodiment 2
Other conditions are same as Example 1, the difference is that adjusting solution pH value with 10% glacial acetic acid is 6, other test conditions
Identical as 1, the sample is at 45 DEG C, and after 3 hours, measuring COD removal efficiency is 72%.
Embodiment 3
Other conditions are same as Example 1, the difference is that adjusting solution pH value with 10% glacial acetic acid is 4, other test conditions
Identical as 1, the sample is at 45 DEG C, and after 3 hours, measuring COD removal efficiency is 70%.
Embodiment 4
Other conditions are same as Example 1, the difference is that the ratio of A:B is 2:1, other test conditions are identical as 1, described
Sample is at 45 DEG C, and after 3 hours, measuring COD removal efficiency is 75%.
Embodiment 5
Other conditions are same as Example 1, the difference is that the ratio of A:B is 1:2, other test conditions are identical as 1, described
Sample is at 45 DEG C, and after 3 hours, measuring COD removal efficiency is 74%.
Embodiment 6
Other conditions are same as Example 1, the difference is that: sodium nitrite 15%, sodium peroxydisulfate 17%, other test conditions
Identical as 1, the sample is at 45 DEG C, and after 3 hours, measuring COD removal efficiency is 78%.It is poor compared with Example 1.
Embodiment 7
Other conditions are same as Example 1, the difference is that Zero-valent Iron 10%, sodium sulfite 12%, ferrous sulfate 5%, other surveys
Strip part is identical as 1, and the sample is at 45 DEG C, and after 3 hours, measuring COD removal rate is 75%.
Embodiment 8
Other conditions are same as Example 1, the difference is that Zero-valent Iron 5%, sodium sulfite 17%, ferrous sulfate 8%, other surveys
Strip part is identical as 1, and the sample is at 45 DEG C, and after 3 hours, measuring COD removal rate is 80%.It is poor compared with Example 1.
Embodiment 9
Other conditions are same as Example 1, the difference is that Zero-valent Iron 7%, sodium sulfite 12%, ferrous sulfate 5%, other surveys
Strip part is identical as 1, and the sample is at 45 DEG C, and after 3 hours, measuring COD removal rate is 62%.
Embodiment 10
Other conditions are same as Example 1, the difference is that Zero-valent Iron 10%, sodium sulfite 12%, ferrous sulfate 5%, other surveys
Strip part is identical as 1, and the sample is at 45 DEG C, and after 3 hours, measuring COD removal rate is 72%.It is poor compared with Example 1.
Embodiment 11
Other conditions are same as Example 1, the difference is that Zero-valent Iron 10%, sodium sulfite 12%, ferrous sulfate 5%, other surveys
Strip part is identical as 1, and the sample is at 45 DEG C, and after 3 hours, measuring COD removal rate is 66%.
Embodiment 12
Other conditions are same as Example 1, the difference is that sodium nitrite 12%, sodium peroxydisulfate 21%, sodium sulfite 12%, sulphur
Sour ferrous iron 5%, other test conditions are identical as 1, and the sample is at 45 DEG C, and after 3 hours, measuring COD removal rate is 72%.
Embodiment 13
Other conditions are same as Example 1, the difference is that: sodium nitrite 14%, sodium peroxydisulfate 18%, Zero-valent Iron 6%, sulfurous
Sour sodium 16%, ferrous sulfate 7%, other test conditions are identical as 1, and the sample after 3 hours, measures COD removal rate at 45 DEG C
It is 72%.
By the comparison of embodiment 1, embodiment 2, embodiment 3 as it can be seen that when the oxidant is when PH is 5 or so, COD is removed
Rate is best, and when PH is 4 ~ 6, COD removal rate has decline.By embodiment 4, embodiment 5 as it can be seen that A:B compared with embodiment 1
When=1:1, the COD removal effect of oxidant is best.By embodiment 1 and embodiment 6, embodiment 7, embodiment 8, embodiment 9, reality
The comparison of example 10, embodiment 11, embodiment 13 is applied as it can be seen that the variation of the ratio of each component has an impact to COD removal effect, but
When in the variation range of actual concentrations ± 3% described in embodiment 1, the removal rate of COD is 70% or more, when continuing growing,
The removal effect decline of COD is obvious.
In conclusion the sample in the present invention has excellent removal capacity for COD in waste water.Sample preparation letter
It is single, the hypersaline environment in waste water can be overcome, had a good application prospect.
It should be pointed out that for those skilled in the art, the present invention is not limited to the above embodiments, is not departing from
Under the premise of general idea of the present invention, several changes and improvements of component ratio can also be made, these also should be considered as this hair
Bright protection scope.
Claims (4)
1. a kind of oxidant for removing high-salt wastewater COD organic matter, it is characterised in that: compounded by the raw material of following weight percent
Form: sodium nitrite 12-15%, sodium peroxydisulfate 17-21%, Zero-valent Iron 5-10%, sodium sulfite 12-17%, ferrous sulfate 5-8%,
Remaining is water.
2. the preparation method of the oxidant of removal high-salt wastewater COD organic matter as described in claim 1, it is characterised in that: by
Following steps composition:
(1) configuration of component A: being sequentially added in water by sodium nitrite, sodium peroxydisulfate, sulfuric acid, is stirred evenly, is filled under room temperature
It is saved in storage vat；
(2) configuration of component B: Zero-valent Iron, sodium sulfite, ferrous sulfate are mixed, is stirred evenly under room temperature, is filled to storage vat
Middle preservation；
(3) compounding mixing: component A, component B are mixed in proportion, obtain oxidant after mixing evenly.
3. the preparation method of the oxidant of removal high-salt wastewater COD organic matter as claimed in claim 2, it is characterised in that: institute
It states after high-salt wastewater is added when oxidant uses, adjusting its solution Ph is 4-6.
4. the preparation method of the oxidant of removal high-salt wastewater COD organic matter as claimed in claim 2, it is characterised in that: institute
State component A in step (3), the mixed weight ratio of component B is 1:(0.5-2).
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111675305A (en) * | 2020-06-13 | 2020-09-18 | 北京胜德永信环保生物技术发展有限公司 | Organic wastewater oxidation treatment method and application thereof |
| CN113620396A (en) * | 2021-06-10 | 2021-11-09 | 雷红卫 | COD (chemical oxygen demand) remover and using method thereof |
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Application publication date: 20190924 |