CN111875018A - Flocculating agent for treating sewage in livestock breeding land and preparation method thereof - Google Patents
Flocculating agent for treating sewage in livestock breeding land and preparation method thereof Download PDFInfo
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- CN111875018A CN111875018A CN202010707536.2A CN202010707536A CN111875018A CN 111875018 A CN111875018 A CN 111875018A CN 202010707536 A CN202010707536 A CN 202010707536A CN 111875018 A CN111875018 A CN 111875018A
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- flocculant
- reaction kettle
- livestock breeding
- starch
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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
-
- 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
Abstract
The invention discloses a flocculating agent for treating sewage of livestock breeding land and a preparation method thereof, wherein the flocculating agent comprises the following components in parts by weight: 30-50 parts of starch, 2-4 parts of animal bone glue, 20-40 parts of zeolite, 10-20 parts of attapulgite powder, 3-5 parts of a silane coupling agent, 3-5 parts of dimethyl carbonate and 6-10 parts of acrylamide. The inorganic-organic composite flocculant is prepared by using common raw materials through coupling reaction, and has the advantages of inorganic flocculant and organic flocculant.
Description
Technical Field
The invention relates to the technical field of flocculating agents, in particular to a flocculating agent for treating sewage in a livestock breeding area and a preparation method thereof.
Background
The excrement of the livestock is a precious organic fertilizer raw material and a serious pollution source, and in the livestock breeding field, a large amount of clear water is used for cleaning the breeding field every day, so that a large amount of sewage is discharged every day, and the sewage contains a large amount of organic matters, pathogens and parasites. If the sewage in the livestock breeding land is directly discharged into the environment without proper treatment, the sewage can cause serious pollution to underground water, surface soil and atmosphere, and the health of livestock and nearby residents is seriously influenced. Research data show that the COD concentration in the wastewater of the farm is as high as 5000-2000 mg/L, the ammonia nitrogen concentration is as high as 800-2000 mg/L, and Suspended Substances (SS) exceed the standard by tens of times.
The existing sewage treatment of livestock breeding places mainly comprises a returning mode, a natural treatment mode and an industrial treatment mode, wherein the existing industrial treatment mode mostly adopts an anaerobic-aerobic combined treatment method, and an aerobic technology is used as the post-treatment of anaerobic treatment. However, in the existing treatment process, the cost of aerobic treatment equipment is high, and because the high-concentration organic matters and ammonia nitrogen in the sewage of the livestock breeding area increase the load of microorganisms in an industrial treatment mode, the hydraulic retention time of the wastewater in an aerobic section is long, so that the sewage treatment efficiency is low.
The flocculation method is one of the most economical and practical methods at present, and by adding a flocculating agent to the sewage in a gathering way, insoluble matters or insoluble matters are formed in the sewage and removed after floating, so that the aim of purifying the sewage to a certain degree is fulfilled. The flocculating agent can be divided into three types of inorganic flocculating agent, organic flocculating agent and microbial flocculating agent according to chemical components, and in addition, some mixed and composite flocculating agents exist, the microbial flocculating agent is greatly influenced by the environmental temperature and the pH value of sewage, and the effect in the sewage treatment of the livestock breeding place is not ideal; the inorganic flocculant has the advantages of low price, slow flocculation speed and small formed floccule; the organic flocculant is mainly a polymeric flocculant, has small dosage, high flocculation speed and is not easy to be influenced by the environment, and the organic polymeric flocculant generally has hydrophilic groups of-COO-, -NH-, -OH and the like, can have various structures of chain, ring and the like, and can remove pollutants by utilizing the adsorption and bridging effect, thereby having good decoloration effect, but the cost of sewage treatment can be increased by simply using the organic flocculant. Therefore, the combination of the organic flocculant and the inorganic flocculant can play a role of both in the sewage treatment of the livestock breeding place.
Disclosure of Invention
The invention aims to provide a flocculating agent for treating sewage of a livestock breeding place, which comprises the following components in parts by weight: 30-50 parts of starch, 2-4 parts of animal bone glue, 20-40 parts of zeolite, 10-20 parts of attapulgite powder, 3-5 parts of a silane coupling agent, 3-5 parts of dimethyl carbonate and 6-10 parts of acrylamide.
Preferably, the starch is one or a mixture of more of potato starch, glutinous rice starch, cassava starch and corn starch.
Preferably, the silane coupling agent is KH 570.
Preferably, the preparation method of the flocculant for treating the sewage of the livestock breeding place comprises the following steps:
s1: calcining the attapulgite powder at the temperature of 460-620 ℃ for 2-3 h, grinding and sieving to prepare fine powder with the particle size of 200-400 meshes, and mixing the fine powder with zeolite with the particle size of 1-3 mm according to the mass part ratio for later use;
s2: mixing starch and animal bone glue according to the mass part ratio, adding pure water with the mass being twice that of the mixture, stirring for 40-60 min in a constant-temperature water bath at 75-85 ℃, and adjusting the pH of the mixed solution to 6.5-7.5 by using an acidic regulator/an alkaline regulator;
s3: adding the mixture obtained in the step S1 into the product obtained in the step S2, placing the new mixture into a reaction kettle, adding a proper amount of silane coupling agent into the reaction kettle according to the mass part ratio, stirring, and introducing nitrogen to remove oxygen in the reaction kettle.
S4: adding dimethyl carbonate and acrylamide in a mass ratio into the reaction kettle, fully stirring, slowly dropwise adding a catalyst into the reaction kettle after the dimethyl carbonate and the acrylamide are dissolved, applying ultrasonic-assisted catalysis, keeping the temperature in the reaction kettle constant at 65-85 ℃, and reacting for 150-200 min to obtain a crude flocculant product.
S4: transferring the crude flocculant product obtained in the step S3 into an absolute ethyl alcohol solution, stirring and separating out, washing the precipitate for 4-5 times by using an acetone solution, then carrying out vacuum drying at the temperature of 50-62 ℃, putting the product obtained by vacuum drying into a Soxhlet extractor, extracting by using absolute ethyl alcohol as a solvent, and carrying out vacuum drying on the extracted product at the temperature of 50-62 ℃ for 3 hours to obtain a final flocculant product.
Preferably, the acidic modifier in step S2 is 1 wt% to 2 wt% HCl solution, and the alkaline modifier is 1 wt% to 2 wt% NaOH solution.
Preferably, the catalyst in step S4 is K2S2O8。
Preferably, the ultrasonic frequency of the ultrasonic-assisted catalysis in the step S4 is 20 to 26 kHZ.
The invention has the beneficial effects that:
the inorganic-organic composite flocculant is prepared by using common raw materials through coupling reaction, and has the advantages of inorganic flocculant and organic flocculant.
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to specific embodiments, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.
Example 1:
a flocculating agent for treating sewage in livestock breeding land comprises the following components in parts by weight:
30 parts of corn starch, 4 parts of animal bone glue, 20 parts of zeolite, 12 parts of attapulgite powder, 3 parts of a silane coupling agent, 4 parts of dimethyl carbonate and 10 parts of acrylamide.
The preparation method of the flocculant for treating the sewage of the livestock breeding land comprises the following steps:
s1: calcining the attapulgite powder at the high temperature of 500 ℃ for 2.5h, grinding and sieving to prepare fine powder with the particle size of 200 meshes, and mixing the fine powder with zeolite with the particle size of 1.5mm according to the mass part ratio for later use;
s2: mixing corn starch, animal bone glue and pure water according to a ratio of 15:2:34, stirring in a constant-temperature water bath at 78 ℃ for 40min, testing the pH value of the mixed solution, and adjusting the pH value of the mixed solution to 6.5-7.5 by using an acidic regulator/an alkaline regulator;
s3: adding the mixture obtained in the step S1 into the product obtained in the step S2, placing a new mixture into a reaction kettle, adding a silane coupling agent KH570 into the reaction kettle according to the mass part ratio, stirring, and introducing nitrogen to remove oxygen in the reaction kettle.
S4: adding dimethyl carbonate and acrylamide in a mass ratio into the reaction kettle, fully stirring, and slowly dropwise adding K into the reaction kettle after the dimethyl carbonate and the acrylamide are dissolved2S2O8And applying ultrasonic assisted catalysis with the frequency of 20kHZ, keeping the temperature in the reaction kettle constant at 70 ℃, and reacting for 180min to obtain a crude flocculant product.
S4: transferring the crude flocculant product obtained in the step S3 into an absolute ethyl alcohol solution, stirring and separating out, washing the precipitate for 4 times by using an acetone solution, then carrying out vacuum drying at the temperature of 50 ℃, putting the product obtained by vacuum drying into a Soxhlet extractor, extracting by using absolute ethyl alcohol as a solvent, and carrying out vacuum drying on the extracted product for 3 hours at the temperature of 50 ℃ to obtain a final flocculant product.
In step S2, a 1 wt% -2 wt% HCl solution or a 1 wt% -2 wt% NaOH solution is selected according to the obtained pH value to adjust the pH value.
Example 2:
a flocculating agent for treating sewage in livestock breeding land comprises the following components in parts by weight:
50 parts of corn starch, 3 parts of animal bone glue, 30 parts of zeolite, 18 parts of attapulgite powder, 3 parts of a silane coupling agent, 5 parts of dimethyl carbonate and 8 parts of acrylamide.
The preparation method of the flocculant for treating the sewage of the livestock breeding land comprises the following steps:
s1: calcining the attapulgite powder at the high temperature of 600 ℃ for 3h, grinding and sieving to prepare fine powder with the particle size of 400 meshes, and mixing the fine powder with zeolite with the particle size of 1mm according to the mass part ratio for later use;
s2: mixing corn starch, animal bone glue and pure water according to a ratio of 50:3:106, stirring in a constant-temperature water bath at 85 ℃ for 60min, testing the pH value of the mixed solution, and adjusting the pH value of the mixed solution to 6.5-7.5 by using an acidic regulator/an alkaline regulator;
s3: adding the mixture obtained in the step S1 into the product obtained in the step S2, placing a new mixture into a reaction kettle, adding a silane coupling agent KH570 into the reaction kettle according to the mass part ratio, stirring, and introducing nitrogen to remove oxygen in the reaction kettle.
S4: adding dimethyl carbonate and acrylamide in a mass ratio into the reaction kettle, fully stirring, and slowly dropwise adding K into the reaction kettle after the dimethyl carbonate and the acrylamide are dissolved2S2O8And applying ultrasonic assisted catalysis with the frequency of 26kHZ, keeping the temperature in the reaction kettle constant at 85 ℃, and reacting for 160min to obtain a crude flocculant product.
S4: transferring the crude flocculant product obtained in the step S3 into an absolute ethyl alcohol solution, stirring and separating out, washing the precipitate for 4 times by using an acetone solution, then carrying out vacuum drying at the temperature of 50 ℃, putting the product obtained by vacuum drying into a Soxhlet extractor, extracting by using absolute ethyl alcohol as a solvent, and carrying out vacuum drying on the extracted product for 3 hours at the temperature of 50 ℃ to obtain a final flocculant product.
In step S2, a 1 wt% -2 wt% HCl solution or a 1 wt% -2 wt% NaOH solution is selected according to the obtained pH value to adjust the pH value.
Example 3:
a flocculating agent for treating sewage in livestock breeding land comprises the following components in parts by weight:
45 parts of corn starch, 5 parts of animal bone glue, 40 parts of zeolite, 12 parts of attapulgite powder, 5 parts of a silane coupling agent, 5 parts of dimethyl carbonate and 7 parts of acrylamide.
The preparation method of the flocculant for treating the sewage of the livestock breeding land comprises the following steps:
s1: calcining the attapulgite powder at the temperature of 570 ℃ for 2.5h, grinding and sieving to prepare fine powder with the particle size of 300 meshes, and mixing the fine powder with zeolite with the particle size of 3mm according to the mass part ratio for later use;
s2: mixing corn starch, animal bone glue and pure water according to a ratio of 9:1:10, stirring in a constant-temperature water bath at 80 ℃ for 60min, testing the pH value of the mixed solution, and adjusting the pH value of the mixed solution to 6.5-7.5 by using an acidic regulator/an alkaline regulator;
s3: adding the mixture obtained in the step S1 into the product obtained in the step S2, placing a new mixture into a reaction kettle, adding a silane coupling agent KH570 into the reaction kettle according to the mass part ratio, stirring, and introducing nitrogen to remove oxygen in the reaction kettle.
S4: adding dimethyl carbonate and acrylamide in a mass ratio into the reaction kettle, fully stirring, and slowly dropwise adding K into the reaction kettle after the dimethyl carbonate and the acrylamide are dissolved2S2O8And applying ultrasonic assisted catalysis with the frequency of 26kHZ, keeping the temperature in the reaction kettle constant at 85 ℃, and reacting for 160min to obtain a crude flocculant product.
S4: transferring the crude flocculant product obtained in the step S3 into an absolute ethyl alcohol solution, stirring and separating out, washing the precipitate for 4 times by using an acetone solution, then carrying out vacuum drying at the temperature of 50 ℃, putting the product obtained by vacuum drying into a Soxhlet extractor, extracting by using absolute ethyl alcohol as a solvent, and carrying out vacuum drying on the extracted product for 3 hours at the temperature of 50 ℃ to obtain a final flocculant product.
In step S2, a 1 wt% -2 wt% HCl solution or a 1 wt% -2 wt% NaOH solution is selected according to the obtained pH value to adjust the pH value.
In the 3 embodiments, the compound flocculant is prepared from common raw materials, and starch is a natural high-molecular raw material, so that the prepared flocculant has the advantages of low dosage, biodegradability, no toxicity and no pollution. Natural zeolites have a large pore volume and specific surface area and therefore have high adsorption and high ion exchange properties. The sewage of livestock farm contains a large amount of NH4 +The zeolite has a pore diameter of 0.6-1.5 nm and a pore diameter of 0.3-1.0 nm, both of which are greater than NH4 +Has an ion diameter of 0.29nm, so that the zeolite in the flocculant of the invention can well adsorb NH in wastewater4 +In addition, Na in zeolite+、K+、Ca2+、Mg2+The plasma is also very easy to react with the dirtNH in water4 +The ion exchange occurs, and the structure of the zeolite is not destroyed after the ion exchange, so the flocculating agent of the invention can effectively reduce the NH with extremely high content in the sewage of the livestock farm4 +。
The samples of the flocculating agents prepared in the embodiments 1-3 are put into a sewage pool of a livestock breeding place according to the amount of 0.1%, then are uniformly stirred and are kept stand for 6 hours, the flocculation degrees of the three flocculating agent samples on the sewage of the livestock breeding place reach more than 90%, and the flocculation degree of the flocculating agent sample in the embodiment 2 even reaches 95.8%. Testing COD of the treated wastewaterCrSS value, ammonia nitrogen and total phosphorus are reduced by less than 90 percent relative to the initial values, and the peculiar smell of the sewage is greatly improved.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein. In addition, the technical solutions between the various embodiments can be combined with each other, but must be based on the realization of those skilled in the art; where combinations of features are mutually inconsistent or impractical, such combinations should not be considered as being absent and not within the scope of the claimed invention.
Claims (7)
1. The flocculating agent for treating the sewage of the livestock breeding land is characterized by comprising the following components in parts by weight: 30-50 parts of starch, 2-4 parts of animal bone glue, 20-40 parts of zeolite, 10-20 parts of attapulgite powder, 3-5 parts of a silane coupling agent, 3-5 parts of dimethyl carbonate and 6-10 parts of acrylamide.
2. The flocculant for treating sewage of livestock breeding ground according to claim 1, characterized in that: the starch is one or a mixture of more of potato starch, glutinous rice starch, cassava starch and corn starch.
3. The flocculant for treating sewage from livestock breeding sites according to claim 1, wherein said silane coupling agent is KH 570.
4. The method of producing a flocculating agent for sewage treatment of livestock breeding according to any of claims 1 to 3, characterized by comprising the steps of:
s1: calcining the attapulgite powder at the temperature of 460-620 ℃ for 2-3 h, grinding and sieving to prepare fine powder with the particle size of 200-400 meshes, and mixing the fine powder with zeolite with the particle size of 1-3 mm according to the mass part ratio for later use;
s2: mixing starch and animal bone glue according to the mass part ratio, adding pure water with the mass being twice that of the mixture, stirring for 40-60 min in a constant-temperature water bath at 75-85 ℃, and adjusting the pH of the mixed solution to 6.5-7.5 by using an acidic regulator/an alkaline regulator;
s3: adding the mixture obtained in the step S1 into the product obtained in the step S2, placing the new mixture into a reaction kettle, adding a proper amount of silane coupling agent into the reaction kettle according to the mass part ratio, stirring, and introducing nitrogen to remove oxygen in the reaction kettle.
S4: adding dimethyl carbonate and acrylamide in a mass ratio into the reaction kettle, fully stirring, slowly dropwise adding a catalyst into the reaction kettle after the dimethyl carbonate and the acrylamide are dissolved, applying ultrasonic-assisted catalysis, keeping the temperature in the reaction kettle constant at 65-85 ℃, and reacting for 150-200 min to obtain a crude flocculant product.
S4: transferring the crude flocculant product obtained in the step S3 into an absolute ethyl alcohol solution, stirring and separating out, washing the precipitate for 4-5 times by using an acetone solution, then carrying out vacuum drying at the temperature of 50-62 ℃, putting the product obtained by vacuum drying into a Soxhlet extractor, extracting by using absolute ethyl alcohol as a solvent, and carrying out vacuum drying on the extracted product at the temperature of 50-62 ℃ for 3 hours to obtain a final flocculant product.
5. The method of claim 4, wherein the acidic modifier is 1-2 wt% HCl solution and the alkaline modifier is 1-2 wt% NaOH solution in step S2.
6. The method of claim 4, wherein the catalyst in step S4 is K2S2O8。
7. The method for preparing a flocculating agent for sewage treatment of livestock breeding sites according to claim 4, wherein the ultrasonic frequency of ultrasonic-assisted catalysis in step S4 is 20-26 kHZ.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010707536.2A CN111875018A (en) | 2020-07-21 | 2020-07-21 | Flocculating agent for treating sewage in livestock breeding land and preparation method thereof |
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| CN202010707536.2A CN111875018A (en) | 2020-07-21 | 2020-07-21 | Flocculating agent for treating sewage in livestock breeding land and preparation method thereof |
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| CN111875018A true CN111875018A (en) | 2020-11-03 |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116002834A (en) * | 2023-01-16 | 2023-04-25 | 山东蓝昕环保测试分析有限公司 | Heavy metal organic coupling agent and treatment method applied to sewage treatment |
| CN117228783A (en) * | 2023-09-07 | 2023-12-15 | 河海大学 | Magnetic ecological flocculation material, micro-polluted water treatment device and micro-polluted water treatment method thereof |
| CN117228783B (en) * | 2023-09-07 | 2024-05-17 | 河海大学 | Magnetic ecological flocculation material, micro-polluted water treatment device and micro-polluted water treatment method thereof |
-
2020
- 2020-07-21 CN CN202010707536.2A patent/CN111875018A/en not_active Withdrawn
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116002834A (en) * | 2023-01-16 | 2023-04-25 | 山东蓝昕环保测试分析有限公司 | Heavy metal organic coupling agent and treatment method applied to sewage treatment |
| CN117228783A (en) * | 2023-09-07 | 2023-12-15 | 河海大学 | Magnetic ecological flocculation material, micro-polluted water treatment device and micro-polluted water treatment method thereof |
| CN117228783B (en) * | 2023-09-07 | 2024-05-17 | 河海大学 | Magnetic ecological flocculation material, micro-polluted water treatment device and micro-polluted water treatment method thereof |
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