1. A preparation method of a bio-organic fertilizer with a function of improving a soil structure is characterized by comprising the following steps:

(1) sludge fermentation: adding calcium peroxide powder, porous hydroxyapatite powder and an anaerobic fermentation microbial inoculum into sludge, uniformly mixing, and performing anaerobic fermentation to obtain a sludge fermentation product;

(2) adding crushed crop straws, animal wastes and a fermentation microbial inoculum into the sludge fermentation product prepared in the step (1), uniformly mixing, and performing stack fermentation to prepare a secondary fermentation product for later use;

(3) before use, mixing the calcium peroxide powder, the porous hydroxyapatite powder and the secondary fermentation product prepared in the step (2) to obtain the bio-organic fertilizer with the function of improving the soil structure.

2. The preparation method of the bio-organic fertilizer with the function of improving the soil structure according to claim 1, which is characterized in that: the weight ratio of the calcium peroxide powder to the porous hydroxyapatite powder to the sludge is 0.1-0.4: 0.01-0.03: 1.

3. the preparation method of the bio-organic fertilizer with the function of improving the soil structure according to claim 2, characterized in that: the weight ratio of the calcium peroxide powder to the porous hydroxyapatite powder to the secondary fermentation product is 0.1-0.2: 0.01-0.03: 1.

4. the preparation method of the bio-organic fertilizer with the function of improving the soil structure according to claim 3, characterized in that: the temperature of fermentation in the step (1) is 50-65 ℃.

5. The preparation method of the bio-organic fertilizer with the function of improving the soil structure according to claim 4, characterized in that: and (3) during the stacking fermentation in the step (2), the stacking fermentation time is 60-120 days, and the stacking is turned over for more than 3 times during the fermentation period.

6. The preparation method of the bio-organic fertilizer with the function of improving the soil structure according to claim 5, characterized in that: the organic matter contained in the sludge is below 10%, and the heavy metal contained in the sludge is below an environmental standard value.

7. A bio-organic fertilizer having a function of improving soil structure, which is obtained by the production method according to any one of claims 1 to 7.

Background

The soil hardening refers to the phenomenon that the surface of soil is poor in structure due to lack of organic matters, the structure is damaged and the soil is dispersed under the action of irrigation, rainfall and other external factors, and the surface of the soil is hardened under the action of cohesive force after drying.

The main factors that often contribute to soil hardening are as follows:

1. the organic material investment is less, namely, no organic fertilizer or straw is applied to the field, so that the organic substance in the soil is not sufficiently supplemented, the organic substance content of the soil is low, the physicochemical properties are poor, the activity of microorganisms is influenced, the formation of a soil granular structure is influenced, and the soil is hardened due to too large or too small acidity-basicity.

2. Long-term single application of the fertilizer is deviated, namely the farmyard manure is seriously insufficient, the diazo light phosphorus-potassium fertilizer reduces the organic matters of the soil, and the humus can not be supplemented in time, so that the soil is hardened and cracked.

In order to solve the problem of soil hardening, in the prior art, besides increasing and applying farmyard manure, organic fertilizers have the function of improving soil hardening. However, the organic fertilizer has the problem of poor improvement effect.

Disclosure of Invention

The invention aims to solve the technical problem of providing a biological organic fertilizer with a function of improving the soil structure, and the biological organic fertilizer has a good effect of improving the soil hardening condition.

The second technical problem to be solved by the invention is to provide a method for preparing the bio-organic fertilizer with the function of improving the soil structure.

In order to solve the technical problems, the technical scheme of the invention is as follows:

a preparation method of a bio-organic fertilizer with a function of improving a soil structure comprises the following steps:

(1) sludge fermentation: adding calcium peroxide powder, porous hydroxyapatite powder and an anaerobic fermentation microbial inoculum into sludge, uniformly mixing, and performing anaerobic fermentation to obtain a sludge fermentation product;

(2) adding crushed crop straws, animal wastes and a fermentation microbial inoculum into the sludge fermentation product prepared in the step (1), uniformly mixing, and performing stack fermentation to prepare a secondary fermentation product for later use;

(3) before use, mixing the calcium peroxide powder, the porous hydroxyapatite powder and the secondary fermentation product prepared in the step (2) to obtain the bio-organic fertilizer with the function of improving the soil structure.

Preferably, the weight ratio of the calcium peroxide powder to the porous hydroxyapatite powder to the sludge is 0.1-0.4: 0.01-0.03: 1.

preferably, the weight ratio of the calcium peroxide powder, the porous hydroxyapatite powder and the secondary fermentation product is 0.1-0.2: 0.01-0.03: 1.

preferably, the temperature for fermentation in step (1) is 50-65 ℃.

Preferably, in the step (2), when the stack covering fermentation is performed, the stack covering fermentation time is 60-120 days, and the stack turning is performed for more than 3 times during the fermentation period.

Preferably, the organic matter contained in the sludge is 10% or less, and the heavy metal contained in the sludge is an environmental standard value or less.

The invention also provides the biological organic fertilizer with the function of improving the soil structure, which is prepared by the method.

The invention has the beneficial effects that:

(1) the invention uses the sludge, the crop straws and the animal wastes as raw materials, has low cost, realizes the recycling of wastes, reduces the pollution to the environment and is more environment-friendly.

(2) In the invention, the sludge is mixed with the calcium peroxide powder, the porous hydroxyapatite powder and the anaerobic fermentation microbial inoculum and then fermented, and the sludge can be dewatered and reduced in amount through the fermentation process; particularly, the calcium peroxide powder and the porous hydroxyapatite powder are used in a combined manner, the addition of the porous hydroxyapatite powder can play a role in promoting calcium peroxide, so that the dehydration reduction effect of the sludge is better and obvious, and the prepared sludge fermentation product is better fluffy and breathable; meanwhile, on the basis of the prepared sludge fermentation product, the sludge fermentation product is mixed with crop straws and animal wastes for fermentation again to prepare a secondary fermentation product, so that the content of organic matters is increased, and the requirement of organic fertilizer nutrients is met;

particularly, the secondary fermentation product, the calcium peroxide powder and the porous hydroxyapatite powder are mixed and then used before the organic fertilizer is used, and the improvement effect of the organic fertilizer on hardened soil can be fully guaranteed through the operation mode.

(3) The organic fertilizer can take effect in the same year when used in the same year, the volume weight of the soil is obviously reduced, the permeability is improved, and the pH value of hardened soil can be reduced after the organic fertilizer is used.

The action mechanism of the invention is as follows:

in the process of sludge combination, the calcium peroxide can release hydrogen peroxide and molecular oxygen, on one hand, the sludge is subjected to oxidative degradation, on the other hand, the molecular oxygen is released and overflows into the porous hydroxyapatite powder, and the porous hydroxyapatite powder serving as an accelerant can maintain the long-term release of the hydrogen peroxide and the molecular oxygen of the calcium peroxide, so that the effect is improved; and after the porous hydroxyapatite powder adsorbs molecular oxygen, the volume weight of the soil can be obviously reduced, so that the hardness of the soil is reduced.

Detailed Description

The following examples further illustrate embodiments of the present invention. It should be noted that the description of the embodiments is provided to help understanding of the present invention, but the present invention is not limited thereto. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

Example 1

A preparation method of a bio-organic fertilizer with a function of improving a soil structure comprises the following steps:

(1) sludge fermentation: adding calcium peroxide powder, porous hydroxyapatite powder and an anaerobic fermentation microbial inoculum into sludge, uniformly mixing, and performing anaerobic fermentation in an anaerobic fermentation tank, wherein the temperature is controlled to be 55-65 ℃ in the fermentation process, and the fermentation is performed for 48 hours to obtain a sludge fermentation product; wherein the weight ratio of the calcium peroxide powder to the porous hydroxyapatite powder to the sludge is 0.2: 0.01: 1.

it should be noted that the porous hydroxyapatite powder in this example is prepared by the prior art, and in this example, the porous hydroxyapatite powder is prepared by "a method for preparing porous hydroxyapatite" in CN 108079382B.

In addition, in order to avoid introducing substances harmful to hardened soil, the organic matter contained in the sludge in the embodiment is below 10%, and the heavy metal contained in the sludge is below an environmental standard value.

(2) Adding crushed corn straws, cow dung and a fermentation microbial inoculum into the sludge fermentation product prepared in the step (1), uniformly mixing, stacking and fermenting for 60 days, and turning once every 20 days during the period to prepare a secondary fermentation product for later use;

(3) and (3) when the fertilizer is required to be applied to hardened soil, mixing the calcium peroxide powder and the porous hydroxyapatite powder with the secondary fermentation product prepared in the step (2) to obtain the biological organic fertilizer with the function of improving the soil structure. Wherein the weight ratio of the calcium peroxide powder, the porous hydroxyapatite powder and the secondary fermentation product is 0.18: 0.03: 1.

example 2

A preparation method of a bio-organic fertilizer with a function of improving a soil structure comprises the following steps:

(2) sludge fermentation: adding calcium peroxide powder, porous hydroxyapatite powder and an anaerobic fermentation microbial inoculum into sludge, uniformly mixing, and performing anaerobic fermentation in an anaerobic fermentation tank, wherein the temperature is controlled to be 50-60 ℃ in the fermentation process, and the fermentation is performed for 60 hours to obtain a sludge fermentation product; wherein the weight ratio of the calcium peroxide powder to the porous hydroxyapatite powder to the sludge is 0.1: 0.02: 1.

(2) adding crushed corn straws, pig manure and a fermentation microbial inoculum into the sludge fermentation product prepared in the step (1), uniformly mixing, stacking and fermenting for 90 days, and turning over for more than 3 times at irregular intervals to prepare a secondary fermentation product for later use;

(3) and (3) when the fertilizer is required to be applied to hardened soil, mixing the calcium peroxide powder and the porous hydroxyapatite powder with the secondary fermentation product prepared in the step (2) to obtain the biological organic fertilizer with the function of improving the soil structure. Wherein the weight ratio of the calcium peroxide powder, the porous hydroxyapatite powder and the secondary fermentation product is 0.2: 0.02: 1.

example 3

A preparation method of a bio-organic fertilizer with a function of improving a soil structure comprises the following steps:

(3) sludge fermentation: adding calcium peroxide powder, porous hydroxyapatite powder and an anaerobic fermentation microbial inoculum into sludge, uniformly mixing, and performing anaerobic fermentation in an anaerobic fermentation tank, wherein the temperature is controlled at 52-60 ℃ in the fermentation process, and the fermentation is performed for 72 hours to obtain a sludge fermentation product; wherein the weight ratio of the calcium peroxide powder to the porous hydroxyapatite powder to the sludge is 0.4: 0.02: 1.

(2) adding crushed corn, tobacco straw, cow dung and a fermentation microbial inoculum into the sludge fermentation product prepared in the step (1), uniformly mixing, stacking and fermenting for 120 days, and turning once every 20 days to prepare a secondary fermentation product for later use;

(3) and (3) when the fertilizer is required to be applied to hardened soil, mixing the calcium peroxide powder and the porous hydroxyapatite powder with the secondary fermentation product prepared in the step (2) to obtain the biological organic fertilizer with the function of improving the soil structure. Wherein the weight ratio of the calcium peroxide powder, the porous hydroxyapatite powder and the secondary fermentation product is 0.1: 0.02: 1.

comparative example 1

The same procedure as in example 1 was repeated, except that the porous hydroxyapatite powder was not added in the steps (1) and (3).

Comparative example 2

The same procedure as in example 2 was repeated, except that the porous hydroxyapatite powder was replaced with a conventional hydroxyapatite powder.

In order to verify the use effect of the organic fertilizer in the invention, the organic fertilizer prepared in the examples 1-3 and the comparative examples 1-2 and the common organic fertilizer are adopted to carry out test comparison in soil hardening land.

Wherein the application amount of each mu of soil hardened land is 1200k_gAfter 20-30cm of land is turned over, fertilizer is evenly spread, and then the soil is put into the land by rotary tillage. The water content, soil bulk weight and pH of the soil were measured before and after application, respectively.

The test results are shown in the following table, one soil indicator.

TABLE soil indices before and after application

The test results show that:

the water content, the volume weight and the pH value of the soil are indexes for representing the soil environment condition, and the soil with the pH value of 6.5-7.5 is neutral soil and is suitable for the growth of most crops; the soil volume weight is used for judging the tightness degree of the soil, the soil volume weight can directly reflect the hardening condition of the soil, the soil structure is good, the loose soil volume weight value is lower, and otherwise, the compact hardened soil volume weight value is higher; in addition, the soil moisture content can be used for representing the soil fertility, and the fertility degree of the soil with higher moisture content is also higher.

As can be seen from the table I, compared with the organic fertilizers prepared in the comparative examples 1-2 and the common organic fertilizers, the organic fertilizer prepared by the method in the examples 1-3 of the invention is applied according to the conventional application method, so that the soil volume weight and pH of hardened soil are obviously reduced, the water content of the soil is improved, and the hardening condition of the hardened soil is obviously improved; meanwhile, comparing examples 1 to 3 of the present invention with comparative examples 1 to 2, it can be seen that the soil improvement condition is not the same as that of examples 1 to 3 to which porous hydroxyapatite powder is added, regardless of whether the conventional hydroxyapatite powder is added or the porous hydroxyapatite powder is not added; in addition, comparing the comparative examples 1-2 with common organic fertilizer, it can be seen that the common organic fertilizer can not improve the soil hardening, even can raise the pH of the soil, and the comparative examples 1-2 can improve the soil to some extent, but the effect is still poor.

The embodiments of the present invention have been described in detail with reference to the examples, but the present invention is not limited to the described embodiments. It will be apparent to those skilled in the art that various changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, and the scope of protection is still within the scope of the invention.