阅读说明：本技术 复合碳源组合物及其制备方法和应用 (Composite carbon source composition and preparation method and application thereof ) 是由 张帅 于 2021-10-25 设计创作，主要内容包括：本发明提供了一种复合碳源组合物及其制备方法和应用,所述复合碳源组合物按照质量百分比包括如下组分：20％-30％的多元醇、0.5％-1％的矿物质、3％-5％的有机酸、4％-5％的生物酶、1％-3％的纯碱、20％-40％的葡萄糖、10％-16％的淀粉以及至100％的水。所述复合碳源组合物反硝化效果显著,硝酸盐去除率高,广泛应用于市政生活、印染等污水处理厂。(The invention provides a composite carbon source composition and a preparation method and application thereof, wherein the composite carbon source composition comprises the following components in percentage by mass: 20 to 30 percent of polyhydric alcohol, 0.5 to 1 percent of mineral substance, 3 to 5 percent of organic acid, 4 to 5 percent of biological enzyme, 1 to 3 percent of soda ash, 20 to 40 percent of glucose, 10 to 16 percent of starch and up to 100 percent of water. The composite carbon source composition has the advantages of remarkable denitrification effect and high nitrate removal rate, and is widely applied to sewage treatment plants in municipal life, printing and dyeing and the like.)

1. The composite carbon source composition is characterized by comprising the following components in percentage by mass:

2. the composite carbon source composition according to claim 1, wherein the polyol has a molecular weight of 100 or less.

3. The composite carbon source composition of claim 1, wherein the polyol comprises at least one of ethylene glycol, propylene glycol, and glycerol.

4. The composite carbon source composition according to claim 3, wherein the polyol comprises 55-65% of ethylene glycol, 5-15% of propylene glycol and 20-40% of glycerol, based on the total mass of the polyol.

5. The composite carbon source composition of claim 1, wherein the minerals comprise at least one of zinc, manganese, and iron.

6. The composite carbon source composition according to claim 5, wherein the minerals comprise 5-15% zinc, 25-35% manganese and 55-65% iron, based on the total mass of the minerals.

7. The composite carbon source composition of claim 1, wherein the organic acid comprises at least one of acetic acid and propionic acid.

8. The composite carbon source composition according to claim 7, wherein the organic acid comprises 70-90% acetic acid and 10-30% propionic acid, based on the total mass of the organic acid.

9. The composite carbon source composition of claim 1, wherein the bio-enzyme comprises at least one of pectinase, glucose oxidase, and lignocellulose.

10. The composite carbon source composition according to claim 9, wherein the bio-enzyme comprises 25-35% pectinase, 35-45% glucose oxidase, and 25-35% lignocellulose enzyme, based on the total mass of the bio-enzyme.

11. Use of a composite carbon source composition according to any one of claims 1 to 10 in wastewater treatment.

12. A method of preparing a composite carbon source composition according to any one of claims 1 to 10, the method comprising sequentially performing the steps of:

adding sodium carbonate into a reaction kettle, and then adding polyalcohol, glucose and starch into the reaction kettle;

diluting the mineral substance with water, and adding into a reaction kettle;

diluting the organic acid with water, and then adding the diluted organic acid into a reaction kettle;

diluting the biological enzyme with water, and then adding the diluted biological enzyme into a reaction kettle; and

adding water for dilution.

Technical Field

The invention relates to the technical field of sewage treatment, in particular to a composite carbon source composition, a method for preparing the composite carbon source composition and application of the composite carbon source composition.

Background

The eutrophication situation of the water body is more and more severe, and China puts forward higher discharge limit standards for urban sewage treatment plants. The most widely applied sewage treatment plants at home and abroad are biological nitrogen and phosphorus removal, chemical phosphorus removal and the combination of the two methods.

The exceeding of the total nitrogen of the wastewater is always a chronic disease of a sewage treatment system, and the wastewater containing excessive nitride is discharged into ditches and riverways, so that the eutrophication of water bodies can be caused, and the ecological environment balance is influenced. Nowadays, biological nitrification and denitrification processes are widely applied to denitrification treatment. However, the sewage treatment plant generally has the problem of insufficient denitrification carbon source, and the lack of carbon source seriously restricts the biological denitrification efficiency.

The biological denitrification is to use organic carbon source as an electron donor and nitrate nitrogen as an electron acceptor to remove NO by denitrifying bacteria under the anoxic condition_xConversion of-N to-N₂Thereby achieving the purpose of removing the total nitrogen.

The variety of the additional carbon sources is various, and the carbon sources used conventionally mainly comprise methanol, sodium acetate, glucose, starch and the like. The sodium acetate solution is a conventional sewage treatment agent for colony culture, and in order to improve the culture speed of colonies during use, the sodium acetate solution needs to have higher Chemical Oxygen Demand (COD) and increase Biochemical Oxygen Demand (BOD), and the pH value is controlled to be 6-9.

In the prior art, in order to increase the COD value, a high carbon source auxiliary agent needs to be added, but the increase of the COD value can reduce the pH value of the solution, so that the whole solution system is acidic, and the subsequent sewage treatment amount is increased. In addition, when the COD value is increased and the solution is stored at normal temperature, the solution is easy to crystallize and precipitate, and the using effect is influenced.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a composite carbon source composition which can effectively remove nitrate nitrogen in sewage and does not generate crystallization phenomenon during normal-temperature storage, a method for preparing the composite carbon source composition and application of the composite carbon source composition.

In one aspect, a composite carbon source composition according to an exemplary embodiment may include the following components in mass percent:

according to an exemplary embodiment, the polyol has a molecular weight of 100 or less.

According to an exemplary embodiment, the polyol may include at least one of ethylene glycol, propylene glycol, and glycerin. Preferably, the polyol comprises from 55% to 65% ethylene glycol, from 5% to 15% propylene glycol and from 20% to 40% glycerol, based on the total mass of the polyol. Preferably, the polyol comprises 60% ethylene glycol, 10% propylene glycol and 30% glycerol, based on the total mass of the polyol.

According to an exemplary embodiment, the mineral may include at least one of zinc, manganese, and iron. Preferably, the mineral comprises 5-15% zinc, 25-35% manganese and 55-65% iron, based on the total mass of the mineral. Preferably, the mineral comprises 10% zinc, 30% manganese and 60% iron, based on the total mass of the mineral.

According to an exemplary embodiment, the organic acid may include at least one of acetic acid and propionic acid. Preferably, the organic acid comprises 70-90% acetic acid and 10-30% propionic acid, based on the total mass of the organic acid. Preferably, the organic acid comprises 80% acetic acid and 20% propionic acid, based on the total mass of the organic acid.

According to an exemplary embodiment, the biological enzyme may include at least one of pectinase, glucose oxidase, and lignocellulose enzyme. Preferably, the biological enzymes comprise 25-35% pectinase, 35-45% glucose oxidase and 25-35% lignocellulose enzyme, based on the total mass of the biological enzymes. Preferably, the biological enzyme comprises 30% pectinase, 40% glucose oxidase and 30% lignocellulose enzyme, based on the total mass of the biological enzyme.

On the other hand, the composite carbon source composition according to the exemplary embodiment may be used for sewage treatment.

On the other hand, the method of preparing the composite carbon source composition according to exemplary embodiments may include sequentially performing the following steps:

adding sodium carbonate into a reaction kettle, and then adding polyalcohol, glucose and starch into the reaction kettle;

diluting the mineral substance with water, and adding into a reaction kettle;

diluting the organic acid with water, and then adding the diluted organic acid into a reaction kettle;

diluting the biological enzyme with water, and then adding the diluted biological enzyme into a reaction kettle; and

adding water for dilution.

The technical idea of the present invention is briefly described above. The invention develops a composite carbon source composition and a preparation method thereof, and performs a denitrification effect test. The composite carbon source composition has the advantages of remarkable denitrification effect, high nitrate removal rate and no crystallization phenomenon after long-term normal-temperature storage. In addition, the method disclosed by the invention is clear, simple to operate, good in economic benefit, free of pollution and strong in applicability, can be widely applied to sewage treatment plants in municipal life, printing and dyeing and the like, and can be used for reducing the operation cost.

Drawings

The accompanying drawings are included to provide a further understanding of the disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the disclosure and, together with the description, serve to explain the principles of the disclosure. In the drawings:

fig. 1 is a graph showing the denitrification effect of different carbon sources in example 1 and comparative examples 1 to 3.

Detailed Description

In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of various embodiments or implementations of the invention. As used herein, "examples" and "embodiments" are words of interchangeability, and are non-limiting examples of apparatuses or methods that employ one or more of the inventive concepts disclosed herein. It may be evident, however, that the various embodiments may be practiced without these specific details or with one or more equivalent arrangements. Moreover, the various embodiments may be different, but are not necessarily exclusive.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure is a part. Terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

Denitrification, which refers to the removal of Nitrate (NO) by bacteria₃ ^-) Nitrogen (N) in (A) is passed through a series of intermediates (NO)₂ ^-、NO、N₂O) reduction to nitrogen (N)₂) The biochemical process of (1). The bacteria involved in this process are collectively referred to as denitrifying bacteria. By means of NO₂ ^-And NO₃ ^-Is the final electron acceptor of respiration and reduces nitric acid to nitrogen (N)₂) Known as denitrification or denitrogenation: NO₃ ^-→NO₂ ^-→N₂×) @. Only a few bacteria are able to perform denitrification, and this physiological population is called denitrifying bacteria. Most denitrifying bacteria are heterotrophic bacteria, which use organic matter as a nitrogen source and energy source for anaerobic respiration.

The invention provides a composite carbon source composition which does not generate crystallization phenomenon after being stored at normal temperature for a long time. The composite carbon source composition has the advantages of remarkable denitrification effect and high nitrate removal rate, can be widely applied to sewage treatment plants in municipal life, printing and dyeing and the like, and reduces the operation cost.

Hereinafter, the complex carbon source composition according to the present invention will be described in detail with reference to exemplary embodiments.

The composite carbon source composition according to the exemplary embodiment may include the following components in percentage by mass:

in an embodiment according to the inventive concept, the main component of the complex carbon source may be a polyol. In embodiments, the molecular weight of the polyol may be 100 or less. Compared with carbon sources such as acetic acid, sodium acetate and the like, the denitrification efficiency of the single polyhydric alcohol with the molecular weight of less than or equal to 100 is slightly low, but under the condition that mineral substances, organic acid and biological enzyme are simultaneously introduced into the formula, the organic acid and the biological enzyme act together to excite the surface activity of microorganisms, greatly improve the absorption efficiency of the microorganisms on the polyhydric alcohol, and enable the composite carbon source composition to have higher denitrification efficiency. In addition, the composite carbon source composition according to the exemplary embodiment of the present invention can achieve higher denitrification efficiency with only a small amount of polyol, relative to a single component of carbon source such as acetic acid, sodium acetate, etc.

In an embodiment according to the inventive concept, the polyol may include at least one of ethylene glycol, propylene glycol, and glycerin, but is not limited thereto. Preferably, the polyol may include 55% to 65% ethylene glycol, 5% to 15% propylene glycol, and 20% to 40% glycerin, based on the total mass of the polyol. Preferably, the polyol may include 60% ethylene glycol, 10% propylene glycol, and 30% glycerol, based on the total mass of the polyol. The physical properties of the polyhydric alcohol are stable, the polyhydric alcohol is not easy to volatilize, is not easy to burn and explode, is high in safety, and meanwhile, the molecular weight of the selected polyhydric alcohol is less than or equal to 100, so that the absorption of microorganisms can be promoted.

In an embodiment according to the inventive concept, the minerals may include at least one of zinc, manganese, and iron, but are not limited thereto. Mineral elements such as zinc, manganese, iron and the like can promote the propagation of microorganisms, enhance the diversity of system microorganisms, and cooperate with two carbon sources such as polyhydric alcohol and organic acid, so that the carbon nutrition demand of the system can be ensured, the diversity of the system microorganisms is enhanced, the good properties of activated sludge in a biochemical system can be maintained, the impact resistance of the system is improved, and the improvement of denitrification efficiency is facilitated. In an embodiment, the mineral may include 5-15% zinc, 25-35% manganese, and 55-65% iron, based on the total mass of the mineral. Preferably, the minerals may include 10% zinc, 30% manganese and 60% iron, based on the total mass of the minerals.

In an embodiment according to the inventive concept, the organic acid may include at least one of acetic acid and propionic acid, but is not limited thereto. Acetic acid and propionic acid can be assisted to adjust the pH of the denitrification accelerant, and simultaneously can be absorbed and decomposed by microorganisms, so that the total nitrogen removal efficiency is improved. In an embodiment, the organic acid may include 70% to 90% acetic acid and 10% to 30% propionic acid, based on the total mass of the organic acid. Preferably, the organic acid may include 80% acetic acid and 20% propionic acid, based on the total mass of the organic acid.

In an embodiment according to the inventive concept, the bio-enzyme may include at least one of pectinase, glucose oxidase, and lignocellulose enzyme, but is not limited thereto. Pectinase can degrade the pectin among cells, and glucose oxidase can oxidize glucose to generate D-glucolactone in the presence of molecular oxygen and consume oxygen to generate hydrogen peroxide. The lignocellulose can degrade cellulose into glucose, so that the denitrification efficiency of the denitrification promoter is further improved. In an embodiment, the biological enzymes may comprise 25-35% pectinase, 35-45% glucose oxidase, and 25-35% lignocellulose enzyme, based on the total mass of the biological enzymes. Preferably, the biological enzymes may comprise 30% pectinase, 40% glucose oxidase and 30% lignocellulose enzyme, based on the total mass of the biological enzymes.

The composite carbon source composition according to the exemplary embodiment may include the following components in percentage by mass:

in the embodiment according to the inventive concept, the composite carbon source composition can effectively remove nitrate in sewage, has a remarkable denitrification effect, and can be widely applied to sewage treatment plants in municipal life, printing and dyeing and the like.

In another embodiment according to the inventive concept, the method of preparing the composite carbon source composition according to an exemplary embodiment of the present invention may include sequentially performing the following steps:

(1) adding sodium carbonate into a reaction kettle, and then adding polyalcohol, glucose and starch into the reaction kettle;

(2) diluting the mineral substance with water, and adding into a reaction kettle;

(3) diluting the organic acid with water, and then adding the diluted organic acid into a reaction kettle;

(4) diluting the biological enzyme with water, and then adding the diluted biological enzyme into a reaction kettle; and

(5) adding water for dilution.

In the step (1), soda ash can be added into a reaction kettle according to the formula ratio, and then ethylene glycol, propylene glycol, glycerol, glucose and starch which are used as polyhydric alcohols are added into the reaction kettle. In the step (2), the mineral substance may be diluted with water to a suitable mass concentration, and then added into the reaction kettle for reaction at normal temperature. The mass concentration may be 1% to 3%, for example, 2.25%. In the step (3), the organic acid may be diluted with water to a suitable mass concentration, and then added into a reaction kettle for reaction at normal temperature. In an embodiment, the mass concentration may be 6% to 8%, for example, 7%. The organic acid may include at least one of acetic acid and propionic acid, and preferably, the organic acid includes 70% to 90% of acetic acid and 10% to 30% of propionic acid, based on the total mass of the organic acid. For example, the organic acid may comprise 80% acetic acid and 20% propionic acid. In the step (4), the bio-enzyme may be diluted with water to a suitable mass concentration (preferably, the mass concentration may be 6% to 9%, for example, 8%), and then added into the reaction kettle, stirred uniformly, reacted at normal temperature for several hours, post-inspected, and filled to obtain the composite carbon source composition according to the exemplary embodiment.

The method of preparing a composite carbon source composition according to the exemplary embodiment is a multi-stage reaction, determines a raw material addition sequence, is strictly controlled, and is strictly formulated in proportion, and thus, uncertainty of a preparation process can be avoided.

The composite carbon source composition according to the exemplary embodiment may have a significant denitrification effect, a high nitrate removal rate, and no crystallization phenomenon during long-term normal temperature storage, and may be widely used for sewage treatment.

The composite carbon source composition according to exemplary embodiments of the inventive concept, the preparation method and the application thereof are described in detail above with reference to exemplary embodiments. Wherein descriptions of well-known techniques are avoided in order to more fully convey the concept of the invention to those skilled in the art.

Hereinafter, the advantageous effects of the present invention will be more clearly understood in conjunction with the examples according to the present invention and the comparative examples.

Of compositions of carbon sourcesPreparation of

[ example 1]

In example 1, the composite carbon source composition may include, in mass percent, 30% of a polyol, 1% of a mineral, 5% of an organic acid, 5% of a bio-enzyme, 3% of soda ash, 30% of glucose, 16% of starch, and 10% of water. The specific preparation method is as follows.

Adding soda ash into a reaction kettle according to the formula ratio, and adding 2.8L of glycol, 1L of propylene glycol, 1.3L of glycerol, 1L of glucose solution and 1L of starch solution which are used as polyhydric alcohols into the reaction kettle. Diluting mineral substances with water to the mass concentration of 2.25%, and adding the mineral substances into a reaction kettle for reaction at normal temperature, wherein the mineral substances comprise 10% of zinc, 30% of manganese and 60% of iron based on the total mass of the mineral substances. Diluting an organic acid with water to a mass concentration of 7%, and adding the diluted organic acid into a reaction kettle for reaction at normal temperature, wherein the organic acid comprises 80% of acetic acid and 20% of propionic acid based on the total mass of the organic acid. Diluting the biological enzyme with water until the mass concentration is 8%, adding the diluted biological enzyme into a reaction kettle, uniformly stirring, reacting at normal temperature for 7 hours, inspecting, and filling a finished product. Wherein the biological enzyme may comprise 30% pectinase, 40% glucose oxidase and 30% lignocellulose enzyme (biosciences technologies, Inc., Toyobo, West Ann), based on the total mass of the biological enzyme. The COD value of the composite carbon source composition is 100 ten thousand, the BOD value is 14.6 ten thousand, the pH value is 6.9, the BOD/COD ratio is 0.146, and the composite carbon source composition does not generate crystallization phenomenon after being stored at normal temperature for 2 months.

[ comparative example 1]

Methanol was used as the sole carbon source.

[ comparative example 2]

Sodium acetate was used as the sole carbon source.

[ comparative example 3]

Glucose was used as the sole carbon source.

Denitrification test

The denitrification test was performed on the complex carbon source composition of example 1 and the single carbon sources in comparative examples 1 to 3. The method comprises the following specific steps:

(1) sampling: taking 6L of a mixed sample of sludge and sewage at the tail end of an aerobic pool of a certain water plant as an experimental sample;

(2) aeration: aerating the obtained muddy water mixed sample for 14 hours;

(3) cleaning: standing the aerated mud-water mixed sample, taking supernatant, cleaning sludge, and cleaning with purified water for 3 times;

(4) mixing: uniformly mixing the cleaned sludge and the supernatant liquid reserved before;

(5) standing: standing the uniformly mixed sludge and supernatant for 30 minutes;

(6) determining the nitrate nitrogen value: measuring the supernatant of the water sample after standing in the step (5), wherein the concentration of nitrate nitrogen is 4.13mg/L, supplementing quantitative potassium nitrate, and converting into nitrate nitrogen which is externally supplemented by about 20mg/L for subsequent tests;

(7) stirring the water sample in the step 6 by using a glass rod to enable muddy water to be uniformly distributed, then adding 900mL of the uniformly distributed muddy water into 5 1000mL beakers, putting the beakers on an electromagnetic stirrer to adjust the rotating speed of magnetic beads, enabling the stirring to generate small vortexes but not enable gas to be sucked, preventing oxygen enrichment stirring for 10 minutes, and consuming and removing dissolved oxygen in water. 100mL of the different carbon sources of example 1 and comparative examples 1 to 3 were added to 4 beakers, respectively, and after stirring uniformly, timing was started for a total of 4 hours for each batch of the test;

(8) the 5 beakers are respectively numbered with blank, blank + methanol, blank + sodium acetate, blank + composite carbon source, and blank + glucose.

(9) Samples were taken every 1 hour. The stirrer is closed and kept stand for 5 minutes during sampling, then 40ml of supernatant is sucked by a pipette, and the nitrate nitrogen content and COD are measured after filtration.

Evaluation of Denitrification Effect

Fig. 1 shows the denitrification effect of the composite carbon source composition of example 1 and the single carbon sources of comparative examples 1 to 3.

As can be seen from FIG. 1, the nitrate nitrogen concentration in 4h was decreased to different degrees with time under the same COD concentration condition in the experimental groups using different carbon sources. The reduction of nitrate nitrogen of the compound carbon source and the sodium acetate group is very obvious, the reduction of nitrate nitrogen of the glucose group is small, and the reduction of nitrate nitrogen of the methanol group is minimum. The nitrate nitrogen of the composite carbon source group is reduced by 14.83mg/L within 4h, and the nitrate removal rate is 64.5 percent. The nitrate nitrogen of the sodium acetate experimental group is reduced by 12.48mg/L, and the nitrate removal rate is 53.5%. Therefore, the denitrification effect of the composite carbon source prepared according to the exemplary embodiment of the present invention is significant.

Therefore, the nitrate removal rate using the composite carbon source composition according to the exemplary embodiment of the inventive concept is significantly higher than that using the single carbon source according to the comparative example of the related art.

Through summarization and review, the invention develops a composite carbon source composition and a preparation method thereof, and performs a denitrification effect test. The composite carbon source composition has the advantages of remarkable denitrification effect, high nitrate removal rate and no crystallization phenomenon after long-term normal-temperature storage. In addition, the method disclosed by the invention is clear, simple to operate, good in economic benefit, free of pollution and strong in applicability, can be widely applied to sewage treatment plants in municipal life, printing and dyeing and the like, and can be used for reducing the operation cost.

Example embodiments have been disclosed herein and, although specific terms are employed, they are used and are to be interpreted in a generic and descriptive sense only and not for purposes of limitation. In some instances, features, characteristics and/or elements described in connection with a particular embodiment may be used alone, or in combination with features, characteristics and/or elements described in connection with other embodiments, as would be apparent to one of ordinary skill in the art upon submission of the present application, unless explicitly stated otherwise. It will therefore be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as set forth in the appended claims.