CN115259151A

CN115259151A - High-alkalinity biochar and preparation method and application thereof

Info

Publication number: CN115259151A
Application number: CN202210697239.3A
Authority: CN
Inventors: 王胜涛; 韩瑞; 王振兴; 蔡高亚; 吕刚
Original assignee: China Construction Eighth Engineering Division Co Ltd
Current assignee: China Construction Eighth Engineering Division Co Ltd
Priority date: 2022-06-20
Filing date: 2022-06-20
Publication date: 2022-11-01

Abstract

The invention provides a preparation method of high-alkalinity biochar, which comprises the following steps: (1) Respectively crushing and mixing the dried edible fungus cultivation residue and the frozen aquatic product processing leftovers to obtain a carbon precursor; (2) Uniformly stirring and mixing the carbon precursor and the impregnant, and standing at room temperature to obtain an impregnated product; (3) Carbonizing the impregnated product to obtain a carbonized product; (4) And cooling, cleaning, drying, grinding and sieving the carbonized product to obtain the high-alkalinity biochar. Also provides the prepared high-alkalinity biochar and application thereof. The invention provides a preparation method of high-alkalinity biochar, which takes waste mushroom dregs and aquatic product leftovers as carbon precursors to prepare biochar, not only realizes resource recycling of biomass wastes, but also efficiently activates peroxyacetic acid to degrade antibiotics in livestock and poultry breeding wastewater.

Description

High-alkalinity biochar and preparation method and application thereof

Technical Field

The invention relates to the technical field of environmental engineering, in particular to the technical field of biochar, and particularly relates to high-alkalinity biochar and a preparation method and application thereof.

Background

Biochar has an excellent pore structure, a high specific surface area and rich functional groups, can be applied to activated oxidants (peroxyacetic acid, persulfate and the like) to degrade organic pollutants (medicines and personal care products (PPCPs)) in wastewater, and gradually becomes one of the hot spots in the field of water treatment.

At present, the preparation of biochar is usually completed by taking lignocellulose-containing materials (such as wood, bamboo, coal and the like) as carbonaceous raw materials through the procedures of crushing, activating, heating and carbonizing, washing and purifying, grinding and granulating and the like. The biomass charcoal is prepared by a pyrolysis carbonization method and hydrothermal carbonization.

However, china is a main domestic fungus producing country in the world, which causes huge fungus residue yield in the process of cultivating domestic fungi, thus not only threatening the environment, but also being a great waste of resources. The edible fungus residue is ready-to-eat edible fungus cultivation residue, and the edible fungus cultivation material is mainly prepared from wood chips containing lignin and high cellulose, so that the edible fungus cultivation residue after removal of the edible fungus contains abundant cellulose, lignin vitamins, mineral elements and other bioactive substances. In addition, a large amount of leftovers such as fish scales, fish bones and viscera, shrimp and crab shells and the like generated in the processing and utilization process of aquatic products can reach more than 200 million tons of fish wastes every year, which not only causes environmental pollution, but also is huge waste of biomass resources.

Therefore, it is desirable to provide a highly alkaline charcoal, which can be prepared from edible fungi cultivation residue and aquatic product processing leftovers to realize the recycling of waste resources and protect the ecological environment, and has high alkalinity, which is beneficial to efficiently activating an oxidant and degrading organic pollutants.

Disclosure of Invention

In order to overcome the defects in the prior art, an object of the present invention is to provide a method for preparing high-alkalinity biochar, which can prepare high-alkalinity biochar from edible fungi cultivation residue and aquatic product processing leftovers to realize waste resource recycling and protect ecological environment, and the prepared biochar has high alkalinity, is beneficial to efficiently activating an oxidant to degrade organic pollutants, and is suitable for large-scale popularization and application.

The invention also aims to provide the high-alkalinity biochar which can be prepared by utilizing edible fungi cultivation residue and aquatic product processing leftovers so as to realize the reutilization of waste resources and protect the ecological environment, has high alkalinity, is beneficial to efficiently activating an oxidant to degrade organic pollutants, and is suitable for large-scale popularization and application.

The invention also aims to provide the application of the high-alkalinity biochar in activating the oxidizing agent to degrade the antibiotics in the livestock and poultry breeding wastewater, the high-alkalinity biochar can effectively activate the oxidizing agent to degrade the antibiotics in the livestock and poultry breeding wastewater, and the high-alkalinity biochar is suitable for large-scale popularization and application.

In order to achieve the above object, in a first aspect of the present invention, there is provided a method for preparing highly alkaline biochar, comprising the steps of:

(1) Respectively crushing and mixing the dried edible fungus cultivation residue and the frozen aquatic product processing leftovers to obtain a carbon precursor;

(2) Uniformly stirring and mixing the carbon precursor and an impregnant, and standing at room temperature to obtain an impregnated product;

(3) Carbonizing the impregnated product to obtain a carbonized product;

(4) And cooling, cleaning, drying, grinding and sieving the carbonized product to obtain the high-alkalinity biochar.

Preferably, in the step (1), the dried edible fungus cultivation residue is prepared by cleaning the edible fungus cultivation residue and then naturally drying in the air, and the frozen aquatic product processing leftovers are prepared by cleaning the aquatic product processing leftovers and then freezing at a low temperature.

Preferably, in the step (1), the dried edible fungus cultivation residue is wood rot fungus cultivation residue; the frozen aquatic product processing leftovers are selected from at least one of fish scales, fish viscera, shrimp shells, crab shells, wastes after the processing of the aquaculture shrimps and crabs and fish impurities after the processing of the aquaculture; the mass ratio of the dry edible fungus cultivation residue to the frozen aquatic product processing leftovers is 25-75: 1; the dried edible fungus cultivation residue is crushed to 80-120 meshes, and the frozen aquatic product processing leftovers are crushed to have the particle size of 0.1-0.5 mm.

More preferably, in the step (1), the wood rot fungi cultivation residual slag is at least one selected from among camellia oleifera mushroom cultivation residual slag, shiitake mushroom cultivation residual slag and flammulina velutipes cultivation residual slag; the mass ratio of the dry edible fungus cultivation residue to the frozen aquatic product processing leftovers is 50:1; before crushing the frozen aquatic product processing leftovers, cutting the frozen aquatic product processing leftovers into pieces; and crushing the frozen aquatic product processing leftovers by adopting a crusher.

Preferably, in the step (2), the impregnant is selected from one of phosphoric acid, potassium hydroxide and citric acid; the mass ratio of the impregnant to the carbon precursor is 1-3: 1; the standing treatment time at room temperature is 12-16 hours.

Preferably, in the step (3), the carbonization is performed in a muffle furnace, the carbonization temperature is 400-550 ℃, the carbonization time is 30-90 minutes, and the carbonization is performed under a protective gas, wherein the protective gas is nitrogen or argon.

Preferably, in the step (4), the temperature to which the cooling is performed is room temperature; the cleaning is to use deionized water to clean until the pH is neutral; the drying temperature is 100-110 ℃, and the drying time is 10-15 h; and grinding, sieving and sieving the mixture by a 180-220-mesh sieve.

In a second aspect of the invention, the invention provides high-alkalinity biochar which is characterized by being prepared by the preparation method of the high-alkalinity biochar.

In a third aspect of the invention, the application of the high-alkalinity biochar in activating an oxidant to degrade antibiotics in livestock and poultry breeding wastewater is provided.

Preferably, the oxidizing agent is peroxyacetic acid and the antibiotic is a tetracycline or a macrolide antibiotic.

The invention has the beneficial effects that:

1. the preparation method of the high-alkalinity biochar comprises the following steps: (1) Respectively crushing and mixing the dried edible fungus cultivation residue and the frozen aquatic product processing leftovers to obtain a carbon precursor; (2) Uniformly stirring and mixing the carbon precursor and the impregnant, and standing at room temperature to obtain an impregnated product; (3) Carbonizing the impregnated product to obtain a carbonized product; (4) The carbonized product is cooled, cleaned, dried, ground and sieved to obtain the high-alkalinity biochar, so that the high-alkalinity biochar can be prepared from edible fungus cultivation residual slag and aquatic product processing leftovers to realize the recycling of waste resources and protect the ecological environment, and the prepared biochar has high alkalinity, is favorable for efficiently activating an oxidant to degrade organic pollutants, and is suitable for large-scale popularization and application.

2. The high-alkalinity biochar is prepared by the preparation method of the high-alkalinity biochar, so that the high-alkalinity biochar can be prepared by utilizing edible fungi cultivation residual slag and aquatic product processing leftovers so as to realize the reutilization of waste resources and protect the ecological environment, has high alkalinity, is favorable for efficiently activating an oxidant to degrade organic pollutants, and is suitable for large-scale popularization and application.

3. The high-alkalinity biochar disclosed by the invention is applied to activating the oxidant to degrade the antibiotics in the livestock and poultry breeding wastewater, so that the high-alkalinity biochar can efficiently activate the oxidant to degrade the antibiotics in the livestock and poultry breeding wastewater, and is suitable for large-scale popularization and application.

These and other objects, features and advantages of the present invention will become more fully apparent from the following detailed description and appended drawings, wherein the means, methods and combinations thereof are specifically identified in the specification.

Drawings

FIG. 1 is a schematic flow chart of the method for preparing the high-alkalinity biochar and activating an oxidant to degrade antibiotics in the livestock and poultry breeding wastewater.

Detailed Description

In order to fully utilize waste mushroom dregs and aquatic product leftovers, realize resource recycling of biomass wastes and protect the ecological environment, the inventor provides a preparation method of high-alkalinity biochar through a large amount of researches, and the preparation method comprises the following steps:

(3) Carbonizing the impregnated product to obtain a carbonized product;

In the step (1), the dried edible mushroom cultivation residue and the frozen aquatic product processing leftovers can be prepared by any suitable method, and preferably, in the step (1), the dried edible mushroom cultivation residue is prepared by cleaning the edible mushroom cultivation residue and then naturally drying the residue in the air, and the frozen aquatic product processing leftovers are prepared by cleaning the aquatic product processing leftovers and then freezing the leftovers at a low temperature.

In the step (1), the edible fungus cultivation residue and the aquatic product processing leftovers are cleaned and the edible fungus cultivation residue is frozen at low temperature by any suitable method, and preferably, the edible fungus cultivation residue is cleaned by tap water and then washed by deionized water to remove impurities on the surface of the edible fungus cultivation residue; the washing water product processing leftovers can be washed by tap water firstly and then washed by deionized water so as to remove impurities on the surfaces of aquatic animal substances; the low-temperature freezing is freezing at-10 ℃.

In the step (1), the dried edible fungi cultivation residue can be any suitable edible fungi cultivation residue, the frozen aquatic product processing leftovers can be any suitable aquatic product processing leftovers, the mass ratio of the dried edible fungi cultivation residue to the frozen aquatic product processing leftovers, the crushed mesh number of the dried edible fungi cultivation residue and the crushed particle size of the frozen aquatic product processing leftovers can be determined according to needs, and preferably, in the step (1), the dried edible fungi cultivation residue is wood rot fungi cultivation residue; the frozen aquatic product processing leftovers are selected from at least one of fish scales, fish viscera, shrimp shells, crab shells, wastes after the processing of the aquaculture shrimps and crabs and fish impurities after the processing of the aquaculture; the mass ratio of the dry edible fungus cultivation residue to the frozen aquatic product processing leftovers is 25-75: 1; the dried edible fungus cultivation residue is crushed to 80-120 meshes, and the frozen aquatic product processing leftovers are crushed to have the particle size of 0.1-0.5 mm.

In the step (1), the wood rotting fungi cultivation residual slag can be any suitable wood rotting fungi cultivation residual slag, the mass ratio of the dried edible fungi cultivation residual slag to the frozen aquatic product processing leftovers can be determined according to needs, the frozen aquatic product processing leftovers can be subjected to any suitable pretreatment before being crushed, the crushed frozen aquatic product processing leftovers can be subjected to any suitable equipment, and preferably, in the step (1), the wood rotting fungi cultivation residual slag is selected from at least one of oil tea mushroom cultivation residual slag, mushroom cultivation residual slag and needle mushroom cultivation residual slag, and is preferably mushroom cultivation residual slag; the mass ratio of the dry edible fungus cultivation residue to the frozen aquatic product processing leftovers is 50:1; before crushing the frozen aquatic product processing leftovers, cutting the frozen aquatic product processing leftovers into pieces; and crushing the frozen aquatic product processing leftovers by adopting a crusher.

In the step (2), the impregnant may be any suitable impregnant, the mass ratio of the impregnant to the carbon precursor and the time of the room-temperature standing treatment may be determined as required, and preferably, in the step (2), the impregnant is selected from one of phosphoric acid, potassium hydroxide and citric acid, preferably 85wt% phosphoric acid; the mass ratio of the impregnant to the carbon precursor is 1-3: 1, preferably 1.5 to 2.5:1, more preferably 2.5:1; the time for the standing treatment at room temperature is 12 to 16 hours, preferably 12 hours.

In the step (3), the carbonization can be performed under any suitable conditions, preferably, in the step (3), the carbonization is performed in a muffle furnace, the carbonization temperature is 400-550 ℃, the carbonization temperature is preferably heated to 400-550 ℃ at a heating rate of 5-15 ℃ rise per minute, more preferably, to 450 ℃ at a heating rate of 10 ℃ rise per minute, the carbonization time is 30-90 minutes, preferably 60 minutes, the carbonization is performed under a protective gas, and the protective gas is nitrogen or argon, preferably nitrogen.

In step (4), the temperature to which the cooling is carried out and the sieve through which the grinding and sieving is carried out can be determined as required, the washing can be carried out by any suitable method, the drying can be carried out by any suitable conditions, and preferably, in step (4), the temperature to which the cooling is carried out is room temperature; the cleaning is carried out by using deionized water until the pH value is neutral, namely the pH value of the cleaning solution is close to neutral, namely the pH value is maintained at 6.5-7.0; the drying temperature is 100-110 ℃, preferably 110 ℃, and the drying time is 10-15 h, preferably 10h; and grinding, sieving and sieving the mixture by a 180-220-mesh sieve.

Also provides high-alkalinity biochar which is prepared by the preparation method of the high-alkalinity biochar.

Also provides application of the high-alkalinity biochar in activating an oxidant to degrade antibiotics in livestock and poultry breeding wastewater.

The oxidizing agent may be any suitable oxidizing agent and the antibiotic may be any suitable antibiotic, preferably, the oxidizing agent is peracetic acid and the antibiotic is a tetracycline or a macrolide antibiotic.

In order to clearly understand the technical contents of the present invention, the following examples are given in detail. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. The experimental procedures, in which specific conditions are not noted in the following examples, are generally carried out under conventional conditions or conditions recommended by the manufacturers. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

Example 1

1. Washing mushroom cultivation residue with tap water, washing with deionized water, naturally drying, and pulverizing to 100 mesh; washing fishbone with tap water, washing with deionized water, freezing at-10 ℃, cutting into blocks, and crushing with a crusher to generate pasty biomass with the particle size of 0.5mm, wherein the mass ratio of crushed shiitake mushroom cultivation residue to crushed fishbone powder is 50:1, uniformly mixing to obtain the carbon precursor.

2. Mixing the carbon precursor and 85wt% phosphoric acid in a mass ratio of 1:2.5 soaking for 12h at room temperature to obtain a soaking product.

3. And (3) putting the impregnated product into a muffle furnace protected by nitrogen, wherein the carbonization condition is as follows: the heating rate is 10 ℃ per minute, the temperature is raised to 450 ℃ for carbonization and activation for 60 minutes, and a carbonized product is obtained;

4. cooling the carbonized product to room temperature, washing with boiled deionized water until the pH of the washing waste liquid is close to neutral, drying at 110 ℃ for 10h, and grinding until the waste liquid can pass through a 200-mesh sieve to obtain the biochar A with 200 meshes.

Example 2

1. Washing residues left in the cultivation of the camellia oleifera mushrooms by using tap water, washing by using deionized water, naturally drying, and crushing to 80 meshes; washing shrimp shells with tap water, washing with deionized water, freezing at-10 ℃, cutting into blocks, and crushing with a crusher to generate pasty biomass, wherein the particle size is controlled to be 0.3mm, and the crushed material of the camellia oleifera mushroom cultivation residue and the crushed material of the shrimp shells are 75:1, and uniformly mixing to obtain the carbon precursor.

2. Mixing a carbon precursor and potassium hydroxide in a mass ratio of 1:3, standing at room temperature for 14h to obtain an impregnated product.

3. And (3) putting the impregnated product into a muffle furnace protected by argon, wherein the carbonization conditions are as follows: the heating rate is 5 ℃ per minute, the temperature is raised to 400 ℃ for carbonization and activation for 90 minutes, and a carbonized product is obtained;

4. cooling the carbonized product to room temperature, washing with boiled deionized water until the pH of the washing waste liquid is close to neutral, drying at 105 ℃ for 12h, and grinding until the waste liquid can pass through a 220-mesh sieve to obtain the 220-mesh biochar B.

Example 3

1. Washing residues left in the cultivation of the flammulina velutipes by tap water, washing by deionized water, naturally drying, and crushing to 120 meshes; washing crab shells by using tap water, washing by using deionized water, freezing at the temperature of minus 10 ℃, cutting into blocks, and crushing by using a crusher to generate pasty biomass, wherein the particle size is controlled to be 0.1mm, and the mass ratio of the crushed residues of the flammulina velutipes cultivation to the crushed crab shells is 25:1, uniformly mixing to obtain the carbon precursor.

2. Mixing a carbon precursor and citric acid in a mass ratio of 1:1, standing at room temperature for 16h to obtain an impregnated product.

3. And (3) putting the impregnated product into a muffle furnace protected by nitrogen, wherein the carbonization conditions are as follows: the heating rate is 15 ℃ per minute, the temperature is increased to 550 ℃ for carbonization and activation for 30 minutes, and a carbonized product is obtained;

4. cooling the carbonized product to room temperature, washing with boiled deionized water until the pH of the washing waste liquid is close to neutral, drying at 100 ℃ for 15h, and grinding until the waste liquid can pass through a 180-mesh sieve to obtain the 180-mesh biochar C.

Example 4

1. Washing mushroom cultivation residue with tap water, washing with deionized water, naturally drying, and pulverizing to 100 mesh; washing the fish phosphorus by using tap water, washing by using deionized water, freezing at-10 ℃, cutting into blocks, and crushing by using a crusher to generate pasty biomass, wherein the particle size is controlled to be 0.5mm, and the crushed shiitake mushroom cultivation residue and the crushed fish phosphorus are 75 in mass ratio: 1, uniformly mixing to obtain the carbon precursor.

2. Mixing the carbon precursor and 85wt% phosphoric acid in a mass ratio of 1:1.5 soaking and standing at room temperature for 12h to obtain a soaked product.

3. And (3) putting the impregnated product into a muffle furnace protected by argon, wherein the carbonization conditions are as follows: the heating rate is 10 ℃ per minute, the temperature is raised to 500 ℃ for carbonization and activation for 90 minutes, and a carbonized product is obtained;

4. cooling the carbonized product to room temperature, washing with boiled deionized water until the pH of the washing waste liquid is close to neutral, drying at 100 ℃ for 10h, and grinding until the waste liquid can pass through a 200-mesh sieve to obtain the biochar D with 200 meshes.

Example 5

1. Washing mushroom cultivation residue with tap water, washing with deionized water, naturally drying, and pulverizing to 120 mesh; washing fish viscera with tap water, washing with deionized water, freezing at-10 ℃, cutting into blocks, and crushing with a crusher to obtain pasty biomass with a particle size of 0.3mm, wherein the mass ratio of shiitake cultivation residue crushed material to fish viscera crushed material is 25:1, uniformly mixing to obtain the carbon precursor.

2. Mixing a carbon precursor and potassium hydroxide according to a mass ratio of 1:2.5 soaking at room temperature for 14h to obtain a soaking product.

3. And (3) putting the impregnated product into a muffle furnace protected by nitrogen, wherein the carbonization conditions are as follows: the heating rate is 15 ℃ per minute, the temperature is raised to 400 ℃ for carbonization and activation for 60 minutes, and a carbonized product is obtained;

4. cooling the carbonized product to room temperature, washing with boiled deionized water until the pH of the washing waste liquid is close to neutral, drying at 105 ℃ for 12h, and grinding until the waste liquid can pass through a 180-mesh sieve to obtain 180-mesh biochar E.

Comparative example 1

Comparative example 1 same as example 1 except that only the shiitake cultivation residue was used and no fishbone was added, charcoal I of 200 mesh was obtained.

Comparative example 2

Comparative example 2 same as example 1 except that only fishbone was used and shiitake cultivation residue was not added, charcoal II of 200 mesh was obtained.

Comparative example 3

Comparative example 3 same as example 5 except that only fish entrails were used and shiitake cultivation residue was not added, biochar III of 180 mesh was obtained.

Test example 1

In this test example, the Boehm titration method was used to examine the functional groups on the surface of biochar prepared in examples 1 to 5 and comparative examples 1 to 3, and the results are shown in table 1. The biochar prepared in the examples 1-5 has higher acidic functional groups, basic functional groups and total functional group content (mmol/g) than the biochar prepared in the comparative examples 1-3, and abundant surface functional groups are more favorable for activating peroxyacetic acid to generate free radicals for degrading tetracycline.

TABLE 1 biochar surface functional group content

Test example 2

The waste water of the septic tank of the Shandong Zibo pig farm is used as the waste water for breeding livestock and poultry, and the characteristic indexes of the components of the waste water of the septic tank of the pig farm are shown in Table 2.

TABLE 2 characteristic index of wastewater composition of septic tank in pig farm

Index (I)	Numerical value
		pH value	7.6-7.8
TOC(mg/L)	456.7-530.23
		Tetracycline (mg/L)	598.2-678.23
TN(mg/L)	789.3-956.1
		TP(mg/L)	42.5-56.3

The test example detects the degradation effect of the biochar activated peroxyacetic acid prepared in the examples 1-5 and 1-3 on tetracycline and total organic carbon in the livestock and poultry breeding wastewater, and the detection method comprises the following steps: 100ml of the livestock and poultry breeding wastewater is put into a 250ml conical flask, 1ml of peroxyacetic acid solution with the concentration of 10g/L is added, 50mg of charcoal is added, and the mixture is stirred and reacted for 5 hours at room temperature, wherein the stirring speed is 400rpm. Then filtering with 0.45um filter membrane, taking the filtrate, measuring the concentration of the residual tetracycline and the total organic carbon in the filtrate, and calculating the degradation rate of the tetracycline and the degradation rate of the total organic carbon. The test results are shown in table 3. The biochar activated peroxyacetic acid prepared in examples 1-5 can achieve higher removal rate of tetracycline and total organic carbon in livestock and poultry breeding wastewater than the biochar activated peroxyacetic acid prepared in comparative examples 1-3.

TABLE 3 degradation results of tetracycline and Total organic carbon

Compared with the prior art, the invention has the following beneficial effects:

1. the carbon precursor adopted by the invention has the advantages of easily available raw materials, low cost and simple and convenient manufacturing process.

2. According to the invention, the biochar prepared from the mushroom dregs and the aquatic product leftovers not only realizes the recycling of waste resources, but also protects the ecological environment.

3. The biochar prepared by the method has high alkalinity, and is beneficial to efficiently activating an oxidant to degrade organic pollutants.

Therefore, the invention provides a preparation method of high-alkalinity biochar, which is prepared by taking waste mushroom dregs and aquatic product leftovers as carbon precursors, not only realizes resource recycling of biomass wastes, but also efficiently activates peracetic acid to degrade antibiotics in livestock and poultry breeding wastewater.

In conclusion, the preparation method of the high-alkalinity biochar can utilize the edible fungi cultivation residue and the aquatic product processing leftovers to prepare the high-alkalinity biochar so as to realize the reutilization of waste resources and protect the ecological environment, and the prepared biochar has high alkalinity, is favorable for efficiently activating an oxidant to degrade organic pollutants, and is suitable for large-scale popularization and application.

In this specification, the invention has been described with reference to specific embodiments thereof. It will, however, be evident that various modifications and changes may be made thereto without departing from the broader spirit and scope of the invention. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense.

Claims

1. The preparation method of the high-alkalinity biochar is characterized by comprising the following steps:

(3) Carbonizing the impregnated product to obtain a carbonized product;

2. The method for preparing highly alkaline biochar according to claim 1, wherein in the step (1), the dried edible mushroom cultivation residue is prepared by washing the edible mushroom cultivation residue and then naturally drying in the air, and the frozen aquatic product processing residue is prepared by washing the aquatic product processing residue and then freezing at a low temperature.

3. The method for preparing highly alkaline biochar according to claim 1, wherein in the step (1), the dried edible fungus cultivation residual slag is wood rot fungus cultivation residual slag; the frozen aquatic product processing leftovers are selected from at least one of fish scales, fish viscera, shrimp shells, crab shells, wastes after the processing of the aquaculture shrimps and crabs and fish impurities discarded in the aquaculture; the mass ratio of the dry edible fungus cultivation residue to the frozen aquatic product processing leftovers is 25-75: 1; the dried edible fungus cultivation residue is crushed to 80-120 meshes, and the frozen aquatic product processing leftovers are crushed to have the particle size of 0.1-0.5 mm.

4. The method for preparing highly alkaline biochar according to claim 3, wherein in the step (1), the wood rot fungi cultivation residue is at least one selected from the group consisting of camellia oleifera mushroom cultivation residue, shiitake mushroom cultivation residue, and flammulina velutipes cultivation residue; the mass ratio of the dry edible fungus cultivation residue to the frozen aquatic product processing leftovers is 50:1; before crushing the frozen aquatic product processing leftovers, cutting the frozen aquatic product processing leftovers into pieces; and crushing the frozen aquatic product processing leftovers by adopting a crusher.

5. The method for preparing highly alkaline biochar according to claim 1, wherein in the step (2), the impregnant is selected from one of phosphoric acid, potassium hydroxide and citric acid; the mass ratio of the impregnant to the carbon precursor is 1-3: 1; the standing treatment time at room temperature is 12-16 hours.

6. The method for preparing highly alkaline biochar according to claim 1, wherein in the step (3), the carbonization is carried out in a muffle furnace, the carbonization temperature is 400-550 ℃, the carbonization time is 30-90 minutes, the carbonization is carried out under a protective gas, and the protective gas is nitrogen or argon.

7. The method for preparing highly alkaline biochar as claimed in claim 1, wherein in the step (4), the temperature to which cooling is performed is room temperature; the cleaning is to use deionized water to clean until the pH is neutral; the drying temperature is 100-110 ℃, and the drying time is 10-15 h; and grinding, sieving and sieving the mixture by a 180-220-mesh sieve.

8. An overbased biochar, characterized by being produced by the process for producing an overbased biochar as claimed in any one of claims 1 to 7.

9. The use of the overbased biochar of claim 8 in activating oxidants to degrade antibiotics in livestock and poultry farming wastewater.

10. The use of claim 9, wherein the oxidizing agent is peroxyacetic acid and the antibiotic is tetracycline or a macrolide antibiotic.