CN111115784A

CN111115784A - Degradation agent for degrading nitrite in aquaculture water by using compound nitrification inhibitor and preparation method thereof

Info

Publication number: CN111115784A
Application number: CN202010025289.8A
Authority: CN
Inventors: 杨琼
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-01-10
Filing date: 2020-01-10
Publication date: 2020-05-08

Abstract

The invention provides a degrading agent for degrading nitrite in aquaculture water by using a compound nitrification inhibitor, which comprises, by mass, 5-20% of dicyandiamide, 20-50% of thiourea, 5-10% of EDTA disodium and 20-70% of bentonite. The invention also provides a preparation method and application of the degrading agent for degrading nitrite in the aquaculture water by using the compound nitrification inhibitor. The nitrite degradation agent prepared by the invention has the characteristics of long acting, safety, no toxicity, no side effect, no residue, no pollution, no rebound, environmental friendliness, stable culture water quality and the like, has an effective degradation rate of more than 90% on the nitrite in aquaculture, has a simple preparation method, is economical and practical in formula, has a stable and reliable effect, and is suitable for industrial production.

Description

Degradation agent for degrading nitrite in aquaculture water by using compound nitrification inhibitor and preparation method thereof

Technical Field

The invention relates to the field of aquaculture, in particular to a degrading agent for degrading nitrite in aquaculture water by using a compound nitrification inhibitor and a preparation method thereof.

Background

In the prior aquaculture water body, because a large amount of feed is fed, the residual bait of the aquaculture water body is increased, the excrement is increased, and further, the nitrogen is accumulated in a large amount. The nitrogen is converted into ammonia nitrogen, nitrite nitrogen and nitrate nitrogen through the action of various microorganisms, the three nitrogen are absorbed by algae and aquatic plants on one hand, and in addition, the nitrate nitrogen is converted into nitrogen through the denitrification effect under certain conditions, and the nitrogen escapes from a water body and enters the atmosphere. If the aquaculture water body reaches a certain self-cleaning balance state and no external interference exists (if no disinfectant is used), the nitrogen circulation of the water body can be smoothly and normally carried out and can be continuously in a stable state.

On the other hand, a large amount of residual baits and feces in the high-density, high-strength and intensive aquaculture water consume oxygen in the water, so that Dissolved Oxygen (DO) in the water is reduced or lacked, and thus pathogenic microorganisms can grow and breed in a large amount to attack the aquaculture animals, which is shown as infection or morbidity of the aquaculture animals. The use of disinfectants is the only way to kill pathogens. However, the disinfectant is frequently and excessively used to completely kill beneficial microorganisms and digestive and decomposed pollutants (nitrobacteria and nitrosobacteria) in the water body, and the contents of toxic and harmful substances, namely ammonia nitrogen and nitrite, are increased rapidly.

The toxicity of the overproof nitrite in the aquaculture water body to the aquaculture animals is strong, and the action mechanism is as follows: the blood enters from the gill filaments under the respiration of fishes and shrimps, so that normal hemoglobin is oxidized into methemoglobin, and the methemoglobin cannot be combined with oxygen, so that the capacity of the blood for conveying oxygen is reduced. Even if the oxygen in the aquaculture water is rich, the oxygen supply of organism tissues is insufficient, so that the fish and the shrimp are lack of oxygen, stress reaction is generated, and even the fish and the shrimp die by suffocation.

The nitrite is mainly used for reducing the oxygen supply capacity in the aquatic animal body by ①, disturbing the K + concentration inside and outside the body cells by ② to unbalance the K + concentration so as to destroy the functions of nervous system transmission, skeletal muscle contraction and the like, so that the activity of the aquatic animal is reduced, and destroying the function of an immune system by ③ so as to reduce the resistance of the aquatic animal to pathogenic organisms.

The nitrite in the aquaculture water body has great toxicity and strong toxic action on aquatic animals, and when the concentration of the nitrite in the water body reaches or exceeds 0.15mg/L, the nitrite poisoning is easily caused, and the symptoms are shown as follows: anorexia, slow swimming, slow reaction, fast respiration, floating on water surface, dark body color, and dark red gill filament. Therefore, aquaculture must control the concentration of nitrite, otherwise, the disease is endless.

In the current aquaculture production, nitrite degradation is always a difficult problem, and nitrite poisoning always brings serious economic loss to farmers. In production practice, no specific medicine for rapidly degrading nitrite is available, and various methods and measures can be adopted to relieve and reduce the nitrite concentration.

① the method for degrading nitrite in aquaculture includes increasing dissolved oxygen in aquaculture water by starting an aerator or splashing chemical aerator in the whole pool to accelerate the conversion of nitrite to nitrate, thereby reducing the content of nitrite in water ② the nitrite is degraded by microorganism, the nitrite is degraded by using microbial preparation such as bacillus, photosynthetic bacteria and nitrobacteria, ③ the nitrite is adsorbed or degraded by using water quality regulator prepared from ammonia ion chelating agent, active carbon and adsorbent through ion exchange action, ④ the nitrite is oxidized and decomposed by strong oxidant.

The nitrite degradation method mainly adopts the methods of oxidation, decomposition, chelation, adsorption and the like, has high cost, has the general effective rate of 30-50 percent, and can not meet the production requirements of modern aquaculture.

Based on the production needs of aquaculture, the novel degradable nitrite product which is simple, effective and convenient to use and is environment-friendly is provided, and the method has important significance.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides the degrading agent for degrading the nitrite in the aquaculture water by using the compound nitrification inhibitor and the preparation method thereof, the prepared nitrite degrading agent has the characteristics of long acting, safety, no toxicity, no side effect, no residue, no pollution, no rebound, environmental friendliness, stable aquaculture water quality and the like, the effective degradation rate of the nitrite in the aquaculture is more than 90%, the preparation method is simple, the formula is economical and practical, the effect is stable and reliable, and the degrading agent is suitable for industrial production.

The invention adopts the following technical scheme:

a degrading agent for degrading nitrite in a culture water body by using a compound nitrification inhibitor comprises, by mass, 5% -20% of dicyandiamide, 20% -50% of thiourea, 5% -10% of EDTA disodium and 20% -70% of bentonite.

A preparation method of a degrading agent for degrading nitrite in a culture water body by using a compound nitrification inhibitor comprises the steps of putting 5-20% of dicyandiamide, 20-50% of thiourea, 5-10% of EDTA disodium and 20-70% of bentonite in percentage by mass into a mixer, mixing for 30-40min, standing for 0.5-1h, diluting with water, or making into a sheet shape, or making into particles.

Further, the tablet is prepared by sieving with a 40-50 mesh sieve, and tabletting.

Further, the tablet preparation has a diameter of 8-9mm and a weight of 0.5-0.6 g/tablet.

By using the nitrite degradation agent prepared by the invention, the nitrite in the aquaculture water can degrade more than 90% of the nitrite content within 72-96 hours, and the nitrite concentration can be reduced to a safe range within 48 hours. The compound nitrite nitrification inhibitor degradation agent for the aquaculture water body is suitable for all aquaculture water bodies, including mariculture and freshwater culture, and is suitable for all seawater and freshwater culture varieties of fish, shrimps, crabs, frogs, shellfish and the like.

Detailed Description

The technical solution of the present invention will be clearly and completely described below with reference to the present embodiment.

In an aquaculture water ecosystem, nitrite is a dynamic change process and is continuously generated and converted. However, if the environmental conditions change, such as temperature drop, dissolved oxygen decrease or water quality change (disinfection), nitrite will rapidly accumulate and rise, and thus fish and shrimp are easily harmed.

The inventor of the invention researches and discovers that by using nitrification inhibitors (dicyandiamide and thiourea), ammoniacal nitrogen in aquaculture water can be inhibited from being converted into nitrite (nitrate nitrogen), so that the generation of nitrite is prevented, and the effect of reducing the nitrite is achieved. The nitrification inhibitor dicyandiamide or thiourea is used alone, can effectively inhibit the generation of nitrite and degrade the nitrite, but is easy to rebound, unstable in effect and short in effective time.

The invention uses two nitrification inhibitors, namely dicyandiamide and thiourea, and compounds the synergist disodium ethylene diamine tetraacetic acid (EDTA disodium), and the invention is continuously perfected from 2012 to 2019 through several times of technical scheme adjustment and formula adjustment, from the single nitrification inhibitor to the compound nitrification inhibitor to the synergistic compound nitrification inhibitor, thereby overcoming the defects of easy rebound, instability and drug resistance generation compared with other similar products.

Example 1

A degrading agent for degrading nitrite in a culture water body by using a compound nitrification inhibitor is prepared by putting 5 mass percent of dicyandiamide, 45 mass percent of thiourea, 8 mass percent of EDTA disodium and 42 mass percent of bentonite into a mixer, mixing for 30min, placing for 0.5h, packaging for 500 g/bag, dissolving water during test, and uniformly sprinkling in a whole pool. Nitrite concentration (ppm) was measured before use and again 72 hours after use, the results of which are shown in table 1:

TABLE 12012 years test conditions from 5 months to 8 months

Example 2

A degrading agent for degrading nitrite in a culture water body by using a compound nitrification inhibitor comprises, by mass, 6% of dicyandiamide, 46% of thiourea, 7% of EDTA disodium and 41% of bentonite. Mixing in a mixer for 30min, standing for 0.5h, packaging with 500 g/bag, dissolving water during test, and sprinkling uniformly in the whole pool. Nitrite concentration (ppm) was measured before use and again 72-96 hours after use, the results are shown in Table 2:

TABLE 22015 years 5-9 months test conditions

Example 3

A degrading agent for degrading nitrite in a culture water body by using a compound nitrification inhibitor comprises 8% of dicyandiamide, 42% of thiourea, 10% of EDTA disodium and 40% of bentonite in percentage by mass. Mixing in a mixer for 30min, standing for 0.5h, packaging with 500 g/bag, dissolving water during test, and sprinkling uniformly in the whole pool. Nitrite concentration (ppm) was measured before use and again 72-96 hours after use, the results are shown in Table 3:

TABLE 32017 year 4-9 month test conditions

Example 4

A degrading agent for degrading nitrite in a culture water body by using a compound nitrification inhibitor is prepared from 5 mass percent of dicyandiamide, 50 mass percent of thiourea, 8 mass percent of EDTA disodium and 37 mass percent of bentonite. Mixing in a mixer for 30min, standing for 0.5 hr, sieving with 40 mesh sieve, and tabletting with a tabletting machine to obtain tablet with diameter of 8mm and weight of 0.5 g/tablet. Nitrite concentration (ppm) was measured before use and again 72-96 hours after use, the results are shown in Table 4:

TABLE 42019 year 5-7 month tablet test cases

The nitrite detection method is a special reagent colorimetric test. Testing is carried out within 72-96 hours after use.

The nitrite degradation agent for the aquaculture water prepared by the invention is used in an amount of 400-500 g according to the water depth of 1 meter per mu according to the concentration of nitrite.

Repeated tests of a large-area aquaculture water body from 2012 to 2019 show that: the concentration of nitrite is 0.2 ppm-0.9 ppm, after the nitrite compound nitrification inhibitor degradation agent is applied, the degradation rate can reach more than 92% within 72-96 hours, but about 8% of aquaculture water is still available, the effect is not obvious, and the nitrite compound nitrification inhibitor degradation agent can be related to the bottom material and water quality (dissolved oxygen) of the aquaculture water.

After the nitrite compound nitrification inhibitor degradation agent is used, the water quality of aquaculture water is obviously improved and becomes fresh and cool, the water color is changed from blackening to yellow green, and high-quality water with fertilizer, activity, tenderness and comfort in aquaculture is achieved.

The above description is only an embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A degradation agent for degrading nitrite in aquaculture water by using a compound nitrification inhibitor is characterized in that: the adhesive comprises, by mass, 5-20% of dicyandiamide, 20-50% of thiourea, 5-10% of EDTA disodium and 20-70% of bentonite.

2. A preparation method of a degrading agent for degrading nitrite in aquaculture water by using a compound nitrification inhibitor is characterized by comprising the following steps: putting 5-20% of dicyandiamide, 20-50% of thiourea, 5-10% of EDTA disodium and 20-70% of bentonite in percentage by mass into a mixer, mixing for 30-40min, standing for 0.5-1h, and diluting with water, or making into tablets, or making into particles.

3. The preparation method of the degrading agent for degrading nitrite in aquaculture water by using the compound nitrification inhibitor as claimed in claim 2, wherein the degrading agent comprises the following components: sieving with 40-50 mesh sieve, and tabletting.

4. The preparation method of the degrading agent for degrading nitrite in aquaculture water by using the compound nitrification inhibitor, according to claim 3, is characterized in that: the tablet preparation has a diameter of 8-9mm and a weight of 0.5-0.6 g/tablet.