CN114772861A

CN114772861A - Cultivation sewage circulating purification method

Info

Publication number: CN114772861A
Application number: CN202210500270.3A
Authority: CN
Inventors: 晏荣平; 马磊; 熊旭军
Original assignee: Chongqing Future Green City Environmental Industry Development Co ltd
Current assignee: Chongqing Future Green City Environmental Industry Development Co ltd
Priority date: 2022-05-10
Filing date: 2022-05-10
Publication date: 2022-07-22

Abstract

The invention discloses a method for circularly purifying aquaculture sewage. The invention firstly filters large particles and suspended substances such as livestock hair, excrement and the like by using a water collecting well and a grid, the filtered sewage automatically flows into an adsorption system, then flows into a disinfection tank and a neutralization tank, stays for a period of time, then automatically flows into an artificial wetland, and finally is conveyed into a livestock farm, wherein the adsorption system is a sandwich type purification system formed by sponge, self-made biochar and self-made molecular sieves, and the disinfection tank uses a bactericide compounded by modified quaternary ammonium salt and banana peel. The method for circularly purifying the aquaculture sewage ensures that the aquaculture sewage is high in purification degree, each index is far lower than the national first-level discharge standard, the purified water can be reused in a farm, the secondary cyclic utilization of the sewage is realized, and simultaneously, the planting industry and landscape appreciation are linked, so that higher economic benefit is brought.

Description

Cultivation sewage circulating and purifying method

Technical Field

The invention relates to the technical field of aquaculture sewage treatment, in particular to a method for circularly purifying aquaculture sewage.

Background

Under the background of general encouragement for expanded breeding production in rural areas, livestock and poultry breeding in China is vigorously developed, and in recent years, the development situation of industrialization, scale and regionalization is presented. In the process of breeding livestock and poultry, a large amount of sewage is generated due to the factors of sanitation and cleanness of the farm and the livestock and poultry, natural excretion of the livestock and poultry and the like. If the sewage cannot be effectively treated, the sewage will certainly cause pollution and damage to the surrounding ecological environment, especially the water environment, and particularly, if people and livestock drink the sewage by mistake, the sewage will also cause great adverse effects on the body health of the people and livestock, so that the scientific treatment of the livestock breeding sewage is necessary to be strengthened.

The traditional livestock and poultry breeding is mainly based on production, most pollution control technologies only refer to treatment after production, and the main methods include physical methods, such as precipitation, dehydration, drying and the like of livestock and poultry breeding pollution; chemical methods, such as coagulation, oxidation and disinfection of livestock and poultry breeding pollution; biological methods, such as anaerobic, aerobic and facultative treatment of livestock and poultry breeding pollution; ecological methods, such as pond oxidation, wetland treatment, ecological ditch treatment and the like for livestock and poultry breeding pollution; resource utilization, such as composting, organic fertilizer and feed treatment of livestock and poultry breeding pollution.

The traditional livestock and poultry breeding sewage treatment has the problems of low efficiency and high cost in the treatment of nitrogen and phosphorus. In the prior art, the contradiction between the treatment cost and the low profit and high risk of cultivation is prominent, and the existing facilities do not normally operate due to operation management and operation reasons of operators, so that the development of the cultivation sewage treatment method which has the advantages of low investment, high purification efficiency, low energy consumption, low operation and management cost and simple and convenient operation is of great significance.

Disclosure of Invention

The invention aims to provide a method for circularly purifying aquaculture sewage, which aims to solve the problems in the prior art.

In order to solve the technical problems, the invention provides the following technical scheme: a cultivation sewage circulating purification method is characterized by mainly comprising the following steps:

(1) after passing through an artificial grid, the breeding sewage enters a water collecting well and is lifted to an inclined sieve by a pump, and after being sieved, the filtered sewage is obtained;

(2) the filtered sewage automatically flows into an adsorption system, and the adsorption-treated sewage is obtained after adsorption in the adsorption system;

(3) automatically flowing the adsorption-treated sewage into a disinfection tank containing a bactericide, and standing for 30-40 min to obtain disinfection-treated sewage;

(4) automatically flowing the disinfection treatment sewage into a neutralization tank containing a neutralizer, and standing for 10-20 min to obtain neutralization treatment sewage;

(5) and conveying the neutralized sewage into a farm after the neutralized sewage flows into the artificial wetland.

Further, the grid in the step (1) is made of SS304, and the grid gap is 5 mm; the size of the water collecting well is 4.0m multiplied by 1.5m multiplied by 3.0m, and the retention time is 40 min.

Further, the adsorption system in the step (2) is a plastic barrel with the height of 1.5m and the inner diameter of 1.2m, 20cm of sponge is laid at the bottom of the barrel, 10cm of adsorbent is placed on the sponge, 1 layer of 10cm of sponge is placed on the sponge, and the steps are repeated upwards for 2 times to form the sandwich type artificial purification system.

Further, the preparation method of the adsorbent contained in the adsorption system in the step (2) mainly comprises the following steps:

a. cleaning watermelon peel with distilled water, placing the watermelon peel in an oven, drying at 105 ℃ for 10-12 min, cooling to room temperature, crushing with an agate mortar, and sieving with a 100-mesh sieve to obtain watermelon peel biochar;

b. b, placing the watermelon peel biochar in the step a into a beaker, respectively adding an ammonium sulfide solution with the mass fraction of 20% and 4 times of the mass of the watermelon peel biochar, and potassium ferrate powder with the mass fraction of 0.1 time of the mass of the watermelon peel, adding high-purity water with the mass fraction of 50 times of the mass of the watermelon peel biochar for 8-9 times, stirring for 30min by using a glass rod to prepare a mixed solution, stirring the mixed solution for 6-7 h at the speed of 150r/min at the condition of 80 ℃, drying the mixed solution in a drying oven with the temperature of 105 ℃ for 20-30 min, crushing by using an agate mortar, sieving by using a sieve with 100 meshes to prepare powder, finally placing the powder in a muffle furnace, pyrolyzing for 1h at the temperature of 600 ℃, taking out after natural cooling, and sieving by using a sieve with 100 meshes again to prepare the modified watermelon peel biochar;

c. adding deionized water with the mass 5.06 times of that of sodium hydroxide into sodium hydroxide, cooling a beaker, adding sodium metaaluminate with the mass 0.13 times of that of the sodium hydroxide under the stirring state of a glass rod, continuously stirring for 5-6 min by the glass rod, adding silica sol with the mass 2.34 times of that of the sodium hydroxide after the solution is transparent, uniformly stirring to prepare a mixed solution, sealing the opening of the beaker filled with the mixed solution by using a preservative film, placing the beaker on a heat collection type constant-temperature magnetic stirrer, continuously stirring for 1h at the room temperature at the speed of 150r/min, heating to 60 ℃, and stirring for 4h at the same speed to prepare a mixed solution A;

d. dissolving aluminum sulfate in deionized water 7.89 times the mass of the aluminum sulfate, adding 0.44 times the mass of the aluminum sulfate to obtain white carbon black to prepare a mixed solution B, adding the mixed solution B into the mixed solution A in the step C1 times the mass of the mixed solution, and uniformly stirring to form a mixed solution C;

e. d, putting the stirring magnetons and the mixed solution C in the step d into a drying box of a stainless steel high-pressure reaction kettle with a polytetrafluoroethylene lining, reacting for 24 hours at 80 ℃ to obtain a reaction liquid, cooling to room temperature, taking out the reaction liquid, washing and filtering the reaction liquid by using distilled water with the volume 2 times that of the reaction liquid by using a suction filtration device, and repeating for 7-8 times to obtain a filter cake;

f. e, placing the filter cake in the step e into a constant-temperature drying oven, drying for 12 hours at 100 ℃ to obtain a solid, grinding the solid by using an agate mortar, and sieving by using a 100-mesh sieve to obtain the sodium yttrium oxide molecular sieve;

g. dissolving zirconium sulfate in deionized water with the mass of 25 times that of zirconium sulfate to prepare a zirconium sulfate solution, soaking the sodium yttrium molecular sieve and the zirconium sulfate in the step f for 24 hours according to the volume ratio of 1:1 to prepare a mixed solution, drying the mixed solution in a drying oven at 120 ℃ for 12 hours, and then roasting in a muffle furnace at 500 ℃ for 3 hours to obtain a modified molecular sieve;

h. and (e) uniformly mixing the modified watermelon peel biochar in the step (b) and the modified molecular sieve in the step (g) according to the volume ratio of 5:1 to prepare the adsorbent.

Further, the preparation method of the bactericide in the step (3) mainly comprises the following steps:

A. uniformly mixing long-chain alkyl dimethyl tertiary amine and isopropanol which is 1 time of the mass of the long-chain alkyl dimethyl tertiary amine in a beaker, putting the mixture into a three-neck flask, stirring the mixture at room temperature at the speed of 250r/min for 6 to 7min, adding hydrochloric acid which is 0.14 time of the mass of the long-chain alkyl dimethyl tertiary amine and has the mass fraction of 7.8%, continuously stirring the mixture at the same speed, heating the mixture to 30 to 50 ℃, adding epichlorohydrin which is 0.36 time of the mass of the long-chain alkyl dimethyl tertiary amine, stirring the mixture at the same speed for 25 to 30min, heating the mixture to 70 to 90 ℃, reacting the mixture for 7 to 9h, and stopping heating to prepare reaction liquid;

B. pouring the reaction liquid obtained in the step A into a rotary evaporation bottle, obtaining a light yellow pasty crude product at 85 ℃ under 0.09MPa, cooling to room temperature, pouring an acetone solution with the mass fraction of 30% 50 times of the mass of the reaction liquid, stirring for 7-8 min to obtain a mixed liquid, putting the mixed liquid into a refrigerator, cooling for 6h at 2-3 ℃ to obtain a white precipitate, performing suction filtration and repeated dissolution by using distilled water with the mass of 3 times of the mass of the reaction liquid, repeating the operation for 3-4 times, and drying for 12h at room temperature to obtain the long-chain alkyl dimethyl tertiary amine quaternary ammonium salt;

C. placing the long-chain alkyl dimethyl tertiary amine quaternary ammonium salt in the step B into a three-neck flask, adding acetonitrile with the mass of 0.16 time that of the long-chain alkyl dimethyl tertiary amine quaternary ammonium salt, heating to 70-80 ℃ to obtain a mixed solution, weighing metronidazole with the mass of 0.79 time that of the long-chain alkyl dimethyl tertiary amine quaternary ammonium salt, adding the metronidazole into the mixed solution for 5-6 times, continuing heating, keeping the temperature at 70-80 ℃ for reaction for 12 hours, stopping heating after the reaction is finished to obtain a reaction solution, cooling the reaction solution to room temperature, distilling at 0.09MPa and 40 ℃ to obtain a modified quaternary ammonium salt crude product, washing with acetone with the mass fraction of 30% of the mass fraction of the long-chain alkyl dimethyl tertiary amine quaternary ammonium salt of 10 times, filtering for 9-10 times, and drying at 50 ℃ for 10 hours to obtain the modified quaternary ammonium salt;

D. soaking banana peels in warm water at 30 ℃ for 1 hour, boiling for 2 hours, filtering through 16 layers of gauze to obtain filter residues and a filtrate A, adding water at 10 times of the mass of the banana peels into the filter residues again, boiling for 1 hour, filtering through 16 layers of gauze to obtain a filtrate B, mixing the filtrate A and the filtrate B, concentrating at 60 ℃ for 3-4 hours to obtain a banana peel extracting solution;

E. and D, mixing the modified quaternary ammonium salt obtained in the step C and the banana peel extracting solution obtained in the step D according to the mass ratio of 1:2 to prepare the bactericide.

Further, the neutralizer in the step (4) is prepared by mixing 30g/L of lecithin and 20g/L of Tween-80 in a phosphate buffer solution according to a volume ratio of 1: 1.

Further, the size of the artificial wetland in the step (5) is 40m multiplied by 12m multiplied by 0.8m, the water conservancy gradient is 5%, and the retention time of sewage is 24-72 h; 10mm of broken stones of 10-20 cm are paved at the bottom of the wetland, 5mm coarse gravels of 10-20 cm are paved next, and finally loose clay-loam of 20-40 cm is paved.

Furthermore, the plants of the artificial wetland in the step (5) comprise calamus, canna, algae, eichhornia crassipes, hornworts and calla.

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

the invention adopts the grating, the adsorption filtering tank and the sterilization treatment, and the artificial wetland purifies the breeding sewage to obtain the solid fertilizer and the purified water, so as to achieve the effects of secondary cyclic utilization of the sewage and linkage of the breeding industry, the planting industry and the tourism industry.

Firstly, an adsorption filtration tank is a sandwich type purification system formed by sponge, self-made biochar and self-made molecular sieve; the self-made biochar is prepared from ammonium sulfide, potassium ferrate and watermelon peel, the potassium ferrate can be decomposed to generate potassium hydroxide after being dissolved in water, carbon groups of the watermelon peel biochar react with the potassium hydroxide to generate carbonate during activation, the pore size of the watermelon peel biochar is promoted to be formed, a porous structure is formed, the adsorbability is improved, the ammonium sulfide is subjected to decomposition reaction with cellulose of the watermelon peel at high temperature, and sulfur and amino groups are introduced to perform complexation reaction with heavy metal ions, so that the adsorbability of the modified watermelon peel biochar is improved; the self-made molecular sieve is prepared by modifying a sodium yttrium molecular sieve with zirconium sulfate, performing ion exchange reaction, replacing sodium ions with zirconium ions, grafting the zirconium ions onto the surface of the molecular sieve, and accumulating on the surface of the molecular sieve to form new micropores, so that the micropore volume is increased, the pore diameter of the molecular sieve is increased, and the adsorbability of the self-made molecular sieve is enhanced.

Secondly, a self-made bactericide is adopted in the sterilization treatment process, wherein the self-made bactericide is formed by compounding modified quaternary ammonium salt and banana peel; the modified quaternary ammonium salt is prepared from long-chain alkyl dimethyl tertiary amine quaternary ammonium salt and metronidazole, carbon atoms connected with chlorine atoms in the metronidazole attack nitrogen atoms in the quaternary ammonium salt to generate nucleophilic substitution, metronidazole molecules are introduced into quaternary ammonium salt molecules, so that the modified quaternary ammonium salt molecules contain two quaternary nitrogen ions with positive charges, adsorption on the surface of bacteria is facilitated, the modified quaternary ammonium salt has two hydrophobic groups of long-chain alkyl and the metronidazole and can penetrate into a lipoid layer of thallus cells to cause enzyme inactivation, the combined effect of the two groups enhances the bactericidal property of the modified quaternary ammonium salt, in addition, banana peel contains banana peel, bacteria and fungi can be inhibited from breeding, and the banana peel can be cooperated with the modified quaternary ammonium salt to improve the effect of killing bacteria and viruses.

Finally, the culture sewage passes through a grating and a water collecting well, the sludge is intercepted, the culture sewage is fermented on the spot to form a fertilizer, the filtered wastewater flows into an adsorption filtering tank, the traditional multi-stage adsorption is different, an integrated filtering tank is adopted, nitrogen, phosphorus and heavy metals are simultaneously removed, then the wastewater is sterilized and disinfected, and the wastewater is discharged into an artificial wetland consisting of calamus, canna, algae, eichhornia crassipes, hornworts and calla, the sewage substance is recycled by utilizing the plant combination with landscape and high-efficiency purification effects, so that the multi-party economic cooperation of planting, culture and tourism is achieved, in addition, the introduction of the adsorption filtering tank can effectively relieve the saturation of the artificial wetland, reduce the siltation phenomenon and prolong the service life.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In order to more clearly illustrate the method provided by the invention, the following examples are used for detailed description, and the method for testing each index of the cultivation sewage circulation treatment method in the following examples is as follows:

the water quality indexes such as chemical oxygen demand, total phosphorus, ammonia nitrogen, total nitrogen and the like related by the invention are detected and analyzed according to a water and wastewater analysis and detection method.

The sterilization rate is as follows: sampling at a water inlet and a water outlet of a circulating system respectively, diluting water samples, coating on a beef extract peptone culture medium and an agar culture medium, culturing at a constant temperature of 24 ℃ for 24 hours, observing results, and calculating the sterilization rate.

Example 1

A method for circularly purifying aquaculture sewage mainly comprises the following steps:

(1) after passing through an artificial grid, the breeding sewage enters a water collecting well and is lifted to an inclined sieve by a pump, and after being filtered by the sieve, the filtered sewage is obtained;

(3) automatically flowing the adsorption-treated sewage into a disinfection tank containing a bactericide, and standing for 40min to obtain disinfection-treated sewage;

(4) automatically flowing the sewage after disinfection treatment into a neutralization tank containing a neutralizer, and standing for 20min to obtain neutralized sewage;

(5) and (4) conveying the neutralized sewage into the farm after the neutralized sewage automatically flows into the artificial wetland.

a. cleaning watermelon peel with distilled water, placing in an oven, drying at 105 ℃ for 12min, cooling to room temperature, crushing with an agate mortar, and sieving with a 100-mesh sieve to obtain watermelon peel biochar;

b. b, placing the watermelon peel biochar in the step a into a beaker, respectively adding an ammonium sulfide solution with the mass fraction of 20% and 4 times of the mass of the watermelon peel biochar and potassium ferrate powder with the mass fraction of 0.1 time of the mass of the watermelon peel into the beaker, adding high-purity water with the mass fraction of 50 times of the mass of the watermelon peel biochar into the beaker by 8 times, stirring the mixture for 30min by using a glass rod to prepare a mixed solution, stirring the mixed solution for 7h at the speed of 150r/min at the temperature of 80 ℃, drying the mixed solution in a drying oven at the temperature of 105 ℃ for 30min, crushing the dried mixed solution by using an agate mortar, sieving the crushed mixed solution by using a sieve of 100 meshes to prepare powder, finally placing the powder into a muffle furnace, pyrolyzing the powder for 1h at the temperature of 600 ℃, taking out the powder after natural cooling, and sieving by using the sieve of 100 meshes again to prepare the modified watermelon peel biochar;

c. adding deionized water with the mass 5.06 times of that of sodium hydroxide into sodium hydroxide, cooling a beaker, adding sodium metaaluminate with the mass 0.13 times of that of the sodium hydroxide under the stirring state of a glass rod, continuously stirring for 6min by the glass rod, adding silica sol with the mass 2.34 times of that of the sodium hydroxide after the solution is transparent, uniformly stirring to prepare a mixed solution, sealing the opening of the beaker filled with the mixed solution by using a preservative film, placing the beaker on a heat collection type constant-temperature magnetic stirrer, continuously stirring for 1h at the room temperature at the speed of 150r/min, heating to 60 ℃, and stirring for 4h at the same speed to prepare a mixed solution A;

d. dissolving aluminum sulfate in deionized water 7.89 times the mass of the aluminum sulfate, adding 0.44 times the mass of the aluminum sulfate to obtain white carbon black to prepare a mixed solution B, adding the mixed solution B into the mixed solution A in the step C1 times the mass of the mixed solution B, and uniformly stirring to form a mixed solution C;

e. d, putting the stirring magnetons and the mixed solution C in the step d into a drying box of a stainless steel high-pressure reaction kettle with a polytetrafluoroethylene lining, reacting for 24 hours at 80 ℃ to obtain a reaction liquid, cooling to room temperature, taking out the reaction liquid, washing and filtering the reaction liquid by using distilled water with the volume 2 times that of the reaction liquid by using a suction filtration device, and repeating for 8 times to obtain a filter cake;

g. dissolving zirconium sulfate in deionized water with the mass of 25 times that of zirconium sulfate to prepare a zirconium sulfate solution, soaking the sodium yttrium molecular sieve and the zirconium sulfate in the step f for 24 hours according to the volume ratio of 1:1 to prepare a mixed solution, placing the mixed solution in a drying oven for drying at 120 ℃ for 12 hours, and then roasting in a muffle furnace for 3 hours at 500 ℃ to obtain a modified molecular sieve;

A. uniformly mixing long-chain alkyl dimethyl tertiary amine and isopropanol which is 1 time of the mass of the long-chain alkyl dimethyl tertiary amine in a beaker, putting the mixture into a three-neck flask, stirring the mixture at room temperature for 7min at the speed of 250r/min, adding hydrochloric acid which is 0.14 time of the mass of the long-chain alkyl dimethyl tertiary amine and has the mass fraction of 7.8%, continuously stirring the mixture at the same speed, heating the mixture to 30 ℃, adding epichlorohydrin which is 0.36 time of the mass of the long-chain alkyl dimethyl tertiary amine, stirring the mixture at the same speed for 25min, heating the mixture to 80 ℃, reacting the mixture for 7h, and stopping heating to prepare a reaction solution;

B. pouring the reaction liquid in the step A into a rotary evaporation bottle, obtaining a light yellow pasty crude product at the temperature of 85 ℃ and under the pressure of 0.09MPa, cooling to room temperature, pouring an acetone solution with the mass fraction of 30% and the mass being 50 times of the mass of the reaction liquid, stirring for 8min to obtain a mixed liquid, putting the mixed liquid into a refrigerator, cooling for 6h at the temperature of 2 ℃ to obtain a white precipitate, performing suction filtration and repeated dissolution by using distilled water with the mass being 3 times of the mass of the reaction liquid, repeating the operation for 4 times, and drying for 12h at the room temperature to obtain the long-chain alkyl dimethyl tertiary amine quaternary ammonium salt;

C. placing the long-chain alkyl dimethyl tertiary amine quaternary ammonium salt in the step B into a three-neck flask, adding acetonitrile with the mass of 0.16 time that of the long-chain alkyl dimethyl tertiary amine quaternary ammonium salt, heating to 80 ℃ to obtain a mixed solution, weighing metronidazole with the mass of 0.79 time that of the long-chain alkyl dimethyl tertiary amine quaternary ammonium salt, adding the metronidazole into the mixed solution for 6 times, continuously heating, keeping the temperature at 80 ℃ for reaction for 12 hours, stopping heating after the reaction is finished to obtain a reaction solution, cooling the reaction solution to room temperature, distilling at 0.09MPa and 40 ℃ to obtain a crude modified quaternary ammonium salt product, washing and filtering 10 times by using acetone with the mass fraction of 30% of the long-chain alkyl dimethyl tertiary amine quaternary ammonium salt of 10 times that of the long-chain alkyl dimethyl tertiary amine quaternary ammonium salt of 50 ℃ and drying for 10 hours to obtain the modified quaternary ammonium salt;

D. soaking banana peel in warm water at 30 ℃ 20 times of the mass of the banana peel for 1 hour, boiling for 2 hours, filtering through 16 layers of gauze to obtain filter residue and filtrate A, adding water at 10 times of the mass of the banana peel into the filter residue again, boiling for 1 hour, filtering through 16 layers of gauze to obtain filtrate B, mixing the filtrate A and the filtrate B, and concentrating at 60 ℃ for 4 hours to obtain a banana peel extracting solution;

Further, the size of the artificial wetland in the step (5) is 40m multiplied by 12m multiplied by 0.8m, the water conservancy gradient is 5%, and the sewage retention time is 48 h; 10mm gravels of 15cm are paved at the bottom of the wetland, 5mm coarse gravels of 15cm are paved next, and loose clay-loam of 35cm is paved finally.

Example 2

(4) automatically flowing the sewage after disinfection treatment into a neutralization tank containing a neutralizer, and standing for 20min to obtain purified water.

c. adding deionized water with the mass 5.06 times of that of sodium hydroxide into sodium hydroxide, cooling a beaker, adding sodium metaaluminate with the mass 0.13 times of that of the sodium hydroxide under the stirring state of a glass rod, continuously stirring for 6min by the glass rod, adding silica sol with the mass 2.34 times of that of the sodium hydroxide after the solution is transparent, uniformly stirring to prepare a mixed solution, sealing the opening of the beaker filled with the mixed solution by using a preservative film, putting the beaker on a heat-collecting constant-temperature magnetic stirrer, continuously stirring for 1h at the room temperature at the speed of 150r/min, heating to 60 ℃, and stirring for 4h at the same speed to prepare a mixed solution A;

B. pouring the reaction liquid in the step A into a rotary evaporation bottle, obtaining a light yellow pasty crude product at the temperature of 85 ℃ and under the pressure of 0.09MPa, cooling to room temperature, pouring an acetone solution with the mass fraction of 30% and the mass of 50 times of the mass of the reaction liquid, stirring for 8min to obtain a mixed liquid, putting the mixed liquid into a refrigerator, cooling for 6h at the temperature of 2 ℃ to obtain a white precipitate, performing suction filtration and repeated dissolution by using distilled water with the mass of 3 times of the mass of the reaction liquid, repeating the operation for 4 times, and drying for 12h at the room temperature to obtain the long-chain alkyl dimethyl tertiary amine quaternary ammonium salt;

Example 3

b. adding deionized water with the mass 5.06 times of that of sodium hydroxide into sodium hydroxide, cooling a beaker, adding sodium metaaluminate with the mass 0.13 times of that of the sodium hydroxide under the stirring state of a glass rod, continuously stirring for 6min by the glass rod, adding silica sol with the mass 2.34 times of that of the sodium hydroxide after the solution is transparent, uniformly stirring to prepare a mixed solution, sealing the opening of the beaker filled with the mixed solution by using a preservative film, placing the beaker on a heat collection type constant-temperature magnetic stirrer, continuously stirring for 1h at the room temperature at the speed of 150r/min, heating to 60 ℃, and stirring for 4h at the same speed to prepare a mixed solution A;

c. dissolving aluminum sulfate in deionized water 7.89 times the mass of the aluminum sulfate, adding 0.44 times the mass of the aluminum sulfate to obtain white carbon black to prepare a mixed solution B, adding the mixed solution B into the mixed solution A in the step B1 time the mass of the mixed solution B, and uniformly stirring to form a mixed solution C;

d. c, putting the stirring magnetons and the mixed solution C in the step C into a drying box of a stainless steel high-pressure reaction kettle with a polytetrafluoroethylene lining, reacting for 24 hours at 80 ℃ to obtain reaction liquid, cooling to room temperature, taking out the reaction liquid, washing and filtering the reaction liquid by using distilled water with the volume 2 times that of the reaction liquid by using a suction filtration device, and repeating for 8 times to obtain a filter cake;

e. d, placing the filter cake in the step d into a constant-temperature drying oven, drying for 12 hours at 100 ℃ to obtain a solid, grinding the solid by using an agate mortar, and sieving by using a 100-mesh sieve to obtain the sodium yttrium oxide molecular sieve;

f. dissolving zirconium sulfate in deionized water with the mass of 25 times that of zirconium sulfate to prepare a zirconium sulfate solution, soaking the sodium yttrium molecular sieve and the zirconium sulfate in the step e for 24 hours according to the volume ratio of 1:1 to prepare a mixed solution, placing the mixed solution in a drying oven to dry for 12 hours at 120 ℃, and then roasting for 3 hours at 500 ℃ in a muffle furnace to obtain a modified molecular sieve;

g. uniformly mixing the watermelon peel biochar in the step a and the modified molecular sieve in the step f according to the volume ratio of 5:1 to prepare the adsorbent.

A. uniformly mixing long-chain alkyl dimethyl tertiary amine and isopropanol with the mass being 1 time that of the long-chain alkyl dimethyl tertiary amine in a beaker, putting the mixture into a three-neck flask, stirring the mixture at room temperature at the speed of 250r/min for 7min, then adding hydrochloric acid with the mass fraction being 7.8% and the mass being 0.14 time that of the long-chain alkyl dimethyl tertiary amine, continuing stirring the mixture at the same speed to raise the temperature to 30 ℃, then adding epichlorohydrin with the mass being 0.36 time that of the long-chain alkyl dimethyl tertiary amine, stirring the mixture at the same speed for 25min, heating the mixture to raise the temperature to 80 ℃, reacting the mixture for 7h, and stopping heating to prepare reaction liquid;

C. placing the long-chain alkyl dimethyl tertiary amine quaternary ammonium salt in the step B into a three-neck flask, adding acetonitrile with the mass being 0.16 time of that of the long-chain alkyl dimethyl tertiary amine quaternary ammonium salt, heating to 80 ℃ to obtain mixed liquid, weighing metronidazole with the mass being 0.79 time of that of the long-chain alkyl dimethyl tertiary amine quaternary ammonium salt, adding the metronidazole with the mass being 6 times of that of the long-chain alkyl dimethyl tertiary amine quaternary ammonium salt into the mixed liquid, continuously heating, keeping the temperature at 80 ℃ for reaction for 12 hours, stopping heating after the reaction is finished to obtain reaction liquid, cooling the reaction liquid to room temperature, distilling at 0.09MPa and 40 ℃ to obtain a crude modified quaternary ammonium salt, washing and filtering the crude product with acetone with the mass fraction being 30% of the mass being 10 times of that of the long-chain alkyl dimethyl tertiary amine quaternary ammonium salt for 10 times, and drying the crude product at 50 ℃ for 10 hours to obtain the modified quaternary ammonium salt;

Further, the size of the constructed wetland in the step (5) is 40m multiplied by 12m multiplied by 0.8m, the water conservancy gradient is 5%, and the retention time of sewage is 48 h; 10mm gravels of 15cm are paved at the bottom of the wetland, 5mm coarse gravels of 15cm are paved next, and loose clay-loam of 35cm is paved finally.

Example 4

Further, the grating in the step (1) is made of SS304, and the gap between the gratings is 5 mm; the size of the water collecting well is 4.0m multiplied by 1.5m multiplied by 3.0m, and the retention time is 40 min.

f. e, placing the filter cake in the step e into a constant-temperature drying oven, drying for 12 hours at 100 ℃ to obtain a solid, grinding the solid by using an agate mortar, and sieving the solid by using a 100-mesh sieve to obtain the sodium yttrium oxide molecular sieve;

g. and (f) uniformly mixing the modified watermelon peel biochar in the step (b) and the sodium yttrium molecular sieve in the step (f) according to the volume ratio of 5:1 to prepare the adsorbent.

D. soaking banana peel in warm water at 30 ℃ for 1 hour, boiling for 2 hours, filtering with 16 layers of gauze to obtain filter residue and filtrate A, adding water at 10 times of the mass of banana peel into the filter residue again, boiling for 1 hour, filtering with 16 layers of gauze to obtain filtrate B, mixing the filtrate A and the filtrate B, and concentrating at 60 ℃ for 4 hours to obtain banana peel extract;

Example 5

e. d, putting the stirring magnetons and the mixed solution C in the step d into a drying box of a stainless steel high-pressure reaction kettle with a polytetrafluoroethylene lining, reacting for 24 hours at the temperature of 80 ℃ to obtain reaction liquid, cooling to room temperature, taking out the reaction liquid, washing and filtering the reaction liquid by using distilled water with the volume 2 times that of the reaction liquid by using a suction filtration device, and repeating for 8 times to obtain a filter cake;

h. and (e) uniformly mixing the modified watermelon peel in the step (b) and the modified molecular sieve in the step (g) according to the volume ratio of 5:1 to prepare the adsorbent.

C. soaking banana peel in warm water at 30 ℃ for 1 hour, boiling for 2 hours, filtering with 16 layers of gauze to obtain filter residue and filtrate A, adding water at 10 times of the mass of banana peel into the filter residue again, boiling for 1 hour, filtering with 16 layers of gauze to obtain filtrate B, mixing the filtrate A and the filtrate B, and concentrating at 60 ℃ for 4 hours to obtain banana peel extract;

D. and C, mixing the long-chain alkyl dimethyl tertiary amine quaternary ammonium salt in the step B and the banana peel extracting solution in the step C according to the mass ratio of 1:2 to prepare the bactericide.

Further, the neutralizing agent in the step (4) is prepared by mixing 30g/L lecithin and 20g/L Tween-80 phosphate buffer solution according to the volume ratio of 1: 1.

Example 6

(2) the filtered sewage automatically flows into an adsorption system, and adsorption treatment sewage is obtained after adsorption in the adsorption system;

b. b, placing the watermelon peel biochar in the step a into a beaker, respectively adding an ammonium sulfide solution with the mass fraction of 20% and potassium ferrate powder with the mass fraction of 0.1 time of the watermelon peel, which are 4 times of the mass of the watermelon peel biochar, adding high-purity water with the mass fraction of 50 times of the mass of the watermelon peel biochar for 8 times, stirring for 30min by using a glass rod to prepare a mixed solution, stirring for 7h at the speed of 150r/min at the temperature of 80 ℃, drying for 30min by placing the mixed solution into a 105 ℃ drying oven, crushing by using an agate mortar, sieving by using a 100-mesh sieve to prepare powder, placing the powder into a muffle furnace, pyrolyzing for 1h at the temperature of 600 ℃, taking out after natural cooling, and sieving by using a 100-mesh sieve again to prepare the modified watermelon peel biochar;

Comparative example

b. adding deionized water with the mass 5.06 times of that of sodium hydroxide into sodium hydroxide, cooling a beaker, adding sodium metaaluminate with the mass 0.13 times of that of the sodium hydroxide under the stirring state of a glass rod, continuously stirring for 6min by the glass rod, adding silica sol with the mass 2.34 times of that of the sodium hydroxide after the solution is transparent, uniformly stirring to prepare a mixed solution, sealing the opening of the beaker filled with the mixed solution by using a preservative film, putting the beaker on a heat-collecting constant-temperature magnetic stirrer, continuously stirring for 1h at the room temperature at the speed of 150r/min, heating to 60 ℃, and stirring for 4h at the same speed to prepare a mixed solution A;

d. c, putting the stirring magnetons and the mixed solution C in the step C into a drying box of a stainless steel high-pressure reaction kettle with a polytetrafluoroethylene lining, reacting for 24 hours at 80 ℃ to obtain a reaction liquid, cooling to room temperature, taking out the reaction liquid, washing and filtering the reaction liquid by using distilled water with the volume 2 times that of the reaction liquid by using a suction filtration device, and repeating for 8 times to obtain a filter cake;

e. d, placing the filter cake in the step d into a constant-temperature drying oven, drying for 12 hours at 100 ℃ to obtain a solid, grinding the solid by using an agate mortar, and sieving the ground solid by using a 100-mesh sieve to obtain the sodium yttrium oxide molecular sieve;

f. uniformly mixing the watermelon peel biochar in the step a and the sodium yttrium molecular sieve in the step e according to the volume ratio of 5:1 to prepare the adsorbent.

Effects of the invention

The following table 1 shows the performance analysis results of the cultivation sewage circulation purification method using examples 1 to 6 of the present invention and comparative example.

TABLE 1

Compared with the experimental data of the comparative example, the experimental data of the example 1 shows that the chemical oxygen demand, the total nitrogen, the total phosphorus and the ammonia nitrogen concentration of the purified water of the example 1 are lower, the sterilization rate is better, the adsorbent can perform a complex reaction with the nitrogen and the phosphorus, and the adsorbent has high-efficiency adsorption capacity due to the porous structure of the adsorbent, meanwhile, the bactericide has hydrophobic groups and positive charge ions and can go deep into the somatic cells to inactivate the somatic cells, and the banana pituitin in banana peel enables the sterilization effect of the bactericide to be stronger; from the comparison of the experimental data of the embodiment 1 and the embodiment 2, the chemical oxygen demand, the total nitrogen, the total phosphorus and the ammonia nitrogen concentration of the embodiment 2 are higher, which indicates that the soil layer filler of the artificial wetland can adsorb the residual nitrogen and phosphorus and reduce the concentration of pollutants, and the vegetation depends on the degradation of microorganisms attached to the substrate and the root system of the plant to effectively adsorb the chemical oxygen demand; from the comparison of the experimental data of the embodiment 1 and the embodiment 3, it can be found that the total phosphorus concentration of the embodiment 3 is higher, which indicates that the watermelon peel biochar is not modified, and only has a single microporous structure, small pore diameter and weak phosphorus adsorption capacity, and meanwhile, no sulfur or amino group exists, and the watermelon peel biochar cannot perform a complex reaction with phosphorus, so that the adsorption capacity of the watermelon peel biochar is weak; from the comparison of the experimental data of the embodiment 1 and the embodiment 4, it can be found that the total nitrogen and ammonia nitrogen concentrations of the embodiment 4 are higher, which indicates that the molecular sieve pore size is smaller and the number of micropores is less without modifying the molecular sieve, and meanwhile, the molecular sieve cannot react with nitrogen without zirconium ions, so that the adsorption capacity of the molecular sieve to nitrogen is weak; from the comparison of the experimental data of the example 1 and the example 5, it can be found that the sterilization rate of the example 5 is low, which indicates that the quaternary ammonium salt does not contain the quaternary nitrogen ions with positive charges and cannot be adsorbed on the surface of bacteria without modifying the quaternary ammonium salt, and meanwhile, the quaternary ammonium salt only has one hydrophobic group and cannot enter the interior of the bacterial cells deeply, so that the cells cannot be damaged, and the bacterial concentration in the sewage is high, and the sterilization rate is low; from the comparison of the experimental data of example 1 and example 6, it can be seen that the sterilization rate of example 6 is lower, which indicates that the banana peel essence in the banana peel can effectively inhibit the growth of bacteria and fungi, and if only the modified quaternary ammonium salt is used, the banana peel essence cannot cooperate with the banana peel essence, so that the sterilization effect is not more efficient, and the thallus concentration of the sewage is higher.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Claims

1. A cultivation sewage circulating purification method is characterized by mainly comprising the following steps:

(4) automatically flowing the disinfected sewage into a neutralization tank containing a neutralizer, and standing for 10-20 min to obtain neutralized sewage;

2. The recycling purification method for aquaculture sewage according to claim 1, wherein the grid in step (1) is made of SS304, and the gap between the grids is 5 mm; the size of the water collecting well is 4.0m multiplied by 1.5m multiplied by 3.0m, and the retention time is 40 min.

3. The method for recycling and purifying aquaculture sewage according to claim 2, wherein the adsorption system in step (2) is a plastic barrel with a height of 1.5m and an inner diameter of 1.2m, 20cm of sponge is laid at the bottom of the barrel, 10cm of adsorbent is placed on the sponge, 1 layer of 10cm of sponge is placed on the sponge, and the steps are repeated upwards for 2 times to form the sandwich type artificial purification system.

4. The method for circularly purifying aquaculture sewage according to claim 3, wherein the preparation method of the adsorbent contained in the adsorption system in the step (2) mainly comprises the following steps:

b. b, placing the watermelon peel biochar in the step a into a beaker, respectively adding an ammonium sulfide solution with the mass fraction of 20% and potassium ferrate powder with the mass fraction of 0.1 time of the watermelon peel, which are 4 times of the mass of the watermelon peel biochar, adding high-purity water with the mass fraction of 50 times of the mass of the watermelon peel biochar for 8-9 times, stirring for 30min by using a glass rod to prepare a mixed solution, stirring the mixed solution for 6-7 h at the speed of 150r/min at the temperature of 80 ℃, then placing the mixed solution into a 105 ℃ oven to dry for 20-30 min, crushing by using an agate mortar, sieving by using a sieve of 100 meshes to prepare powder, finally placing the powder into a muffle furnace, pyrolyzing for 1h at the temperature of 600 ℃, taking out after natural cooling, and sieving by using a sieve of 100 meshes again to prepare the modified watermelon peel biochar;

5. The method for recycling and purifying aquaculture sewage according to claim 4, wherein the method for preparing the bactericide in the step (3) mainly comprises the following steps:

B. pouring the reaction liquid in the step A into a rotary evaporation bottle, obtaining a light yellow pasty crude product at the temperature of 85 ℃ and under the pressure of 0.09MPa, cooling to room temperature, pouring an acetone solution with the mass fraction of 30% and the mass of 50 times of the mass of the reaction liquid, stirring for 7-8 min to obtain a mixed liquid, putting the mixed liquid into a refrigerator, cooling for 6h at the temperature of 2-3 ℃ to obtain a white precipitate, performing suction filtration and repeated dissolution by using distilled water with the mass of 3 times of the mass of the reaction liquid, repeating the operation for 3-4 times, and drying for 12h at room temperature to obtain the long-chain alkyl dimethyl tertiary amine quaternary ammonium salt;

C. placing the long-chain alkyl dimethyl tertiary amine quaternary ammonium salt in the step B into a three-neck flask, adding acetonitrile with the mass being 0.16 time of that of the long-chain alkyl dimethyl tertiary amine quaternary ammonium salt, heating to 70-80 ℃ to obtain a mixed solution, then weighing metronidazole with the mass being 0.79 time of that of the long-chain alkyl dimethyl tertiary amine quaternary ammonium salt, adding the metronidazole with the mass being 5-6 times of that of the long-chain alkyl dimethyl tertiary amine quaternary ammonium salt into the mixed solution, continuing heating, keeping the temperature at 70-80 ℃ for reaction for 12 hours, stopping heating after the reaction is finished to obtain a reaction solution, cooling the reaction solution to room temperature, distilling at 0.09MPa and 40 ℃ to obtain a crude modified quaternary ammonium salt, washing and filtering the crude product with acetone with the mass fraction being 30% of the mass fraction being 10 times of that of the long-chain alkyl dimethyl tertiary amine quaternary ammonium salt for 9-10 times, and drying the crude product at 50 ℃ for 10 hours to obtain the modified quaternary ammonium salt;

6. The method for recycling and purifying aquaculture sewage according to claim 5, wherein the neutralizer in the step (4) is a phosphate buffer solution containing 30g/L lecithin and 20g/L Tween-80, and the volume ratio of the neutralizer to the phosphate buffer solution is 1: 1.

7. The method for circularly purifying the aquaculture sewage according to claim 6, wherein the size of the constructed wetland in the step (5) is 40m × 12m × 0.8m, the water conservancy gradient is 5%, and the sewage stays for 24-72 h; 10mm of broken stones of 10-20 cm are paved at the bottom of the wetland, 5mm coarse gravels of 10-20 cm are paved next, and finally loose clay-loam of 20-40 cm is paved.

8. The method for recycling and purifying aquaculture sewage according to claim 7, wherein the plants of the constructed wetland in step (5) are selected from the group consisting of calamus, canna, algae, Eichhornia crassipes, Goldia japonica and calla.