Organic fertilizer based on vinegar residue and preparation method thereof

Abstract

The invention discloses an organic fertilizer based on vinegar lees and a preparation method thereof, and belongs to the technical field of organic fertilizer preparation. The organic fertilizer based on vinegar lees disclosed by the invention comprises the following raw materials in parts by weight: 20-30 parts of vinegar lees, 10-15 parts of livestock and poultry feces, 3-5 parts of feces fermentation agent, 10-20 parts of modified montmorillonite, 10-20 parts of modified zeolite and 5-10 parts of humic acid. The organic fertilizer based on vinegar lees prepared by the invention has an organic matter content of ≥72wt%, a fecal coliform count of ≤6 / g, and a total nutrient mass fraction of ≥16%, which can well enhance soil fertility; the invention effectively passivates heavy metals in the soil through modification of montmorillonite and zeolite, addition of humic acid, and the coordinated use of the three, and inhibits the enrichment of heavy metals in the soil by crops.

Description

Technical Field

[0001] The invention belongs to the technical field of organic fertilizer preparation, and particularly relates to an organic fertilizer based on vinegar dregs and a preparation method thereof. Background Art

[0002] Vinegar is made from wheat bran, sorghum, broken rice and other raw materials through fermentation. In the process of making vinegar, a large amount of by-products - vinegar lees - are produced. The air-dried vinegar lees contain 9.6-20.4% crude protein, 15.1-28% crude fiber, and rich trace elements such as iron, zinc, selenium, and manganese. Therefore, using vinegar lees as raw materials to prepare organic fertilizers and apply them to the cultivation of wheat bran, sorghum, broken rice and other raw materials for making vinegar can achieve circular production and maximize the use of resources.

[0003] Due to human activities, the content of heavy metals in the soil is significantly higher than the original content. Excessive heavy metals can cause plant physiological dysfunction and nutritional imbalance. Moreover, heavy metals are not easily leached with water in the soil and are not degraded by microorganisms. They will accumulate in crops and enter the human body through the food chain, bringing great potential harm.

[0004] Therefore, by using vinegar residue as raw material to prepare organic fertilizer and giving the organic fertilizer good heavy metal passivation ability and the ability to reduce the enrichment of heavy metals in crops, it is possible to reduce the heavy metal content in plants while increasing crop yields. Summary of the invention

[0005] In order to solve the above problems in the prior art, the present invention provides an organic fertilizer based on vinegar dregs and a preparation method thereof.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] One of the technical solutions of the present invention: an organic fertilizer based on vinegar dregs, comprising the following raw materials in parts by weight:

[0008]

[0009] Furthermore, the preparation method of the modified montmorillonite is:

[0010] (1) washing the montmorillonite with water until the pH of the washing solution is 7 to obtain purified montmorillonite;

[0011] (2) immersing the purified montmorillonite obtained in step (1) in a mixed solution of ferric chloride and manganese chloride for modification, and then washing with water until the pH of the washing solution is 7, to obtain iron-manganese-based modified montmorillonite;

[0012] (3) Mixing the iron-manganese-based modified montmorillonite obtained in step (2) with water, and then adding chitosan and stirring to obtain chitosan-iron-manganese-based modified montmorillonite, i.e., the modified montmorillonite.

[0013] Furthermore, in step (2), the preparation method of the mixed solution of ferric chloride and manganese chloride is: mixing a ferric chloride solution with a concentration of 2 to 3 mol / L with a manganese chloride solution with a concentration of 2 to 3 mol / L, the mass volume ratio of the montmorillonite, the ferric chloride solution, and the manganese chloride solution is 1 kg: (5 to 10) L: (5 to 10) L; the impregnation modification time is 20 to 30 min.

[0014] Furthermore, in step (3), the chitosan is an acetic acid solution of chitosan, and the specific preparation method is: dissolving chitosan in 1 vol.% acetic acid, the mass volume ratio of chitosan to acetic acid is (2-3) kg:10 L; the mass volume ratio of the iron-manganese-based modified montmorillonite, chitosan, and water is 1 kg: (2-3) kg: (20-30) L; the mixing temperature is 30-50°C, and the time is 30-60 min; the mixing temperature is 30-50°C, and the time is 10-20 min.

[0015] Furthermore, the preparation method of the modified zeolite is:

[0016] (1) washing the zeolite with water until the pH of the washing solution is 7 to obtain purified zeolite;

[0017] (2) immersing the purified zeolite obtained in step (1) in a hydrochloric acid solution for modification, and then washing with water until the pH of the washing solution is 7, to obtain a hydrochloric acid-modified zeolite;

[0018] (3) The hydrochloric acid modified zeolite obtained in step (2) is immersed in a calcium chloride solution for modification, and then washed with water until the pH of the washing solution is 7, to obtain calcium chloride-hydrochloric acid modified zeolite, i.e., the modified zeolite.

[0019] Furthermore, the concentration of the hydrochloric acid solution is 0.3-0.5 mol / L, the mass volume ratio of the purified zeolite to the hydrochloric acid solution is 1 kg: (10-20) L, and the immersion modification time is 2-3 h.

[0020] Furthermore, in step (3), the concentration of the calcium chloride solution is 1-1.5 mol / L, the mass volume ratio of the hydrochloric acid modified zeolite to the calcium chloride solution is 1 kg: (10-20) L; and the immersion modification time is 20-30 min.

[0021] The second technical solution of the present invention: The method for preparing the organic fertilizer based on vinegar dregs comprises the following steps:

[0022] (1) mixing vinegar dregs with livestock and poultry feces, drying until the moisture content is 50-60 wt %, and then adding a feces fermentation agent for fermentation to obtain a fermentation product;

[0023] (2) The fermentation product obtained in step (1) is mixed with modified montmorillonite and modified zeolite, and subjected to secondary fermentation, and then humic acid is added to obtain the organic fertilizer based on vinegar grains.

[0024] Furthermore, the fermentation temperature is 30-40°C and the time is 10-15 days; the secondary fermentation temperature in step (2) is 60-80°C and the time is 1-2 days.

[0025] The third technical solution of the present invention: the application of the organic fertilizer based on vinegar residue in improving soil fertility and inhibiting the adsorption of heavy metals by plants.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] (1) The organic fertilizer based on vinegar lees prepared by the present invention has an organic matter content of ≥72wt%, a fecal coliform count of ≤6 / g, and a total nutrient mass fraction of ≥16%, which can well enhance soil fertility;

[0028] (2) The present invention effectively passivates heavy metals in the soil and inhibits the accumulation of heavy metals in the soil by crops through modification of montmorillonite and zeolite, addition of humic acid, and the combined use of the three.

[0029] (3) The present invention uses vinegar dregs as raw materials, and the organic fertilizer finally prepared can be applied to the planting of crops used as raw materials for vinegar production, thereby reducing the waste of resources and achieving the recycling of resources to a certain extent. DETAILED DESCRIPTION

[0030] Now, various exemplary embodiments of the present invention are described in detail, and this detailed description should not be considered as a limitation of the present invention, but should be understood as a more detailed description of certain aspects, characteristics and embodiments of the present invention. It should be understood that the terms described in the present invention are only for describing specific embodiments and are not used to limit the present invention.

[0031] In addition, for the numerical range in the present invention, it is understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0032] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0033] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to the skilled artisan. The present invention description and examples are exemplary only.

[0034] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0035] In the following embodiments, the vinegar lees are the vinegar lees purchased from Shanxi Taigu Tongbao Vinegar Co., Ltd. producing Shanxi pure aged vinegar; the montmorillonite is 210321 montmorillonite purchased from Henan Kunhao Biotechnology Co., Ltd.; the zeolite is TYFS001 clinoptilolite purchased from Beipiao Tianyi Zeolite Mining Co., Ltd.; the chitosan is BF chitosan purchased from Xi'an Perfi Biotechnology Co., Ltd.; the cellulose is SJJ009 carboxymethyl cellulose purchased from Dacheng Yibo Chemical Co., Ltd.; the feces fermentation agent is OK0009 biological organic fertilizer fermentation agent purchased from Luoyang Ouke Biotechnology Co., Ltd.; and the humic acid is YN626907128685 sodium humate purchased from Jinan Yunuo Chemical Co., Ltd.

[0036] Example 1

[0037] 1. Preparation of modified montmorillonite

[0038] (1) washing 1 kg of montmorillonite with deionized water until the pH of the washing solution is 7, freeze-drying the washed montmorillonite, crushing and grinding it, and then passing it through a 20-mesh sieve to obtain purified montmorillonite;

[0039] (2) The purified montmorillonite obtained in step (1) is immersed in a mixed solution of ferric chloride and manganese chloride for 30 minutes, wherein the mixed solution of ferric chloride and manganese chloride is prepared by mixing 10L of a 3mol / L ferric chloride solution with 10L of a 3mol / L manganese chloride solution; then, the immersed and modified montmorillonite is washed with deionized water until the pH of the washing solution is 7, and the washed montmorillonite is freeze-dried, crushed and ground, and then passed through a 20-mesh sieve to obtain an iron-manganese-based modified montmorillonite (Fe-Mn-Mt);

[0040] (3) 3 kg of chitosan was dissolved in 10 L of 1 vol.% acetic acid solution and stirred at 60° C. for 2.5 h to obtain an acetic acid solution of chitosan;

[0041] (4) placing the Fe-Mn-Mt obtained in step (2) in 30 L of deionized water, mixing and stirring at 50° C. for 60 min, then adding the chitosan acetic acid solution prepared in step (3), stirring at 50° C. for 20 min, then freeze-drying the chitosan-modified Fe-Mn-Mt, crushing and grinding it, and then passing it through a 20-mesh sieve to obtain chitosan-iron-manganese-based modified montmorillonite (CTS@Fe-Mn-Mt);

[0042] 2. Preparation of modified zeolite

[0043] (1) washing 1 kg of zeolite with deionized water until the pH of the washing solution is 7, freeze-drying the washed zeolite, crushing and grinding it, and then passing it through a 20-mesh sieve to obtain purified zeolite;

[0044] (2) The purified zeolite obtained in step (1) is immersed in a hydrochloric acid solution for modification for 3 h, wherein the concentration of the hydrochloric acid is 0.5 mol / L and the volume is 20 L. Thereafter, the immersed and modified zeolite is freeze-dried, crushed and ground, and then passed through a 20-mesh sieve to obtain a hydrochloric acid-modified zeolite (HCl-Z);

[0045] (3) The hydrochloric acid modified zeolite obtained in step (2) is immersed in a calcium chloride solution for modification for 30 minutes, wherein the concentration of the calcium chloride solution is 1.5 mol / L and the volume is 20 L. After that, the immersed and modified zeolite is freeze-dried, crushed and ground, and then passed through a 20-mesh sieve to obtain a calcium chloride hydrochloric acid modified zeolite (CaCl2-HCl-Z);

[0046] 3. Preparation of organic fertilizer based on vinegar residue

[0047] (1) crushing 1.5 kg of vinegar dregs and mixing them with 0.75 kg of livestock and poultry manure, drying them to a moisture content of 60 wt %, then adding 0.25 kg of manure fermentation agent, and fermenting them at 40° C. for 15 days to obtain a fermentation product;

[0048] (2) The fermentation product prepared in step (1) was mixed with 1 kg of the modified montmorillonite prepared in step 1 and 1 kg of the modified zeolite prepared in step 2, and the mixture was fermented at 80° C. for 2 days, and then 0.5 kg of humic acid was added and stirred for 3 hours to prepare an organic fertilizer based on vinegar lees.

[0049] Example 2

[0050] 1. Preparation of modified montmorillonite

[0051] (1) washing 1 kg of montmorillonite with deionized water until the pH of the washing solution is 7, freeze-drying the washed montmorillonite, crushing and grinding it, and then passing it through a 20-mesh sieve to obtain purified montmorillonite;

[0052] (2) The purified montmorillonite obtained in step (1) is immersed in a mixed solution of ferric chloride and manganese chloride for 25 minutes, wherein the mixed solution of ferric chloride and manganese chloride is prepared by mixing 8L of 2.5mol / L ferric chloride solution with 8L of 2.5mol / L manganese chloride solution; then, the immersed and modified montmorillonite is washed with deionized water until the pH of the washing solution is 7, and the washed montmorillonite is freeze-dried, crushed and ground, and then passed through a 20-mesh sieve to obtain iron-manganese-based modified montmorillonite (Fe-Mn-Mt);

[0053] (3) dissolving 2.5 kg of chitosan in 10 L of 1 vol.% acetic acid solution and stirring at 60° C. for 2.5 h to obtain an acetic acid solution of chitosan;

[0054] (4) placing the Fe-Mn-Mt obtained in step (2) in 25 L of deionized water, mixing and stirring at 40° C. for 45 min, then adding the chitosan acetic acid solution prepared in step (3), stirring at 40° C. for 15 min, then freeze-drying the chitosan-modified Fe-Mn-Mt, crushing and grinding it, and then passing it through a 20-mesh sieve to obtain chitosan-iron-manganese-based modified montmorillonite (CTS@Fe-Mn-Mt);

[0055] 2. Preparation of modified zeolite

[0056] (1) washing 1 kg of zeolite with deionized water until the pH of the washing solution is 7, freeze-drying the washed zeolite, crushing and grinding it, and then passing it through a 20-mesh sieve to obtain purified zeolite;

[0057] (2) The purified zeolite obtained in step (1) was immersed in a hydrochloric acid solution for 2.5 hours, wherein the concentration of the hydrochloric acid was 0.4 mol / L and the volume was 15 L. After that, the immersed and modified zeolite was freeze-dried, crushed and ground, and then passed through a 20-mesh sieve to obtain a hydrochloric acid-modified zeolite (HCl-Z);

[0058] (3) The hydrochloric acid modified zeolite obtained in step (2) is immersed in a calcium chloride solution for modification for 25 minutes, wherein the concentration of the calcium chloride solution is 1.3 mol / L and the volume is 15 L. After that, the immersed and modified zeolite is freeze-dried, crushed and ground, and then passed through a 20-mesh sieve to obtain a calcium chloride hydrochloric acid modified zeolite (CaCl2-HCl-Z);

[0059] 3. Preparation of organic fertilizer based on vinegar residue

[0060] (1) crushing 1.25 kg of vinegar dregs and mixing them with 0.65 kg of livestock and poultry manure, drying them to a moisture content of 55 wt %, then adding 0.2 kg of manure fermentation agent, and fermenting them at 35° C. for 13 days to obtain a fermentation product;

[0061] (2) The fermentation product prepared in step (1) was mixed with 0.75 kg of the modified montmorillonite prepared in step 1 and 0.75 kg of the modified zeolite prepared in step 2, and the mixture was fermented at 70° C. for 1.5 days, and then 0.4 kg of humic acid was added and stirred for 2.5 hours to prepare an organic fertilizer based on vinegar lees.

[0062] Example 3

[0063] 1. Preparation of modified montmorillonite

[0064] (1) washing 1 kg of montmorillonite with deionized water until the pH of the washing solution is 7, freeze-drying the washed montmorillonite, crushing and grinding it, and then passing it through a 20-mesh sieve to obtain purified montmorillonite;

[0065] (2) The purified montmorillonite obtained in step (1) is modified by immersing it in a mixed solution of ferric chloride and manganese chloride for 20 minutes, wherein the mixed solution of ferric chloride and manganese chloride is prepared by mixing 5L of 2mol / L ferric chloride solution with 5L of 2mol / L manganese chloride solution; then, the impregnated modified montmorillonite is washed with deionized water until the pH of the washing solution is 7, and the washed montmorillonite is freeze-dried, crushed and ground, and then passed through a 20-mesh sieve to obtain iron-manganese-based modified montmorillonite (Fe-Mn-Mt);

[0066] (3) dissolving 2 kg of chitosan in 10 L of 1 vol.% acetic acid solution and stirring at 60° C. for 2.5 h to obtain an acetic acid solution of chitosan;

[0067] (4) placing the Fe-Mn-Mt obtained in step (2) in 20 L of deionized water, mixing and stirring at 30° C. for 30 min, then adding the acetic acid solution of chitosan prepared in step (3), stirring at 30° C. for 10 min, then freeze-drying the chitosan-modified Fe-Mn-Mt, crushing and grinding it, and then passing it through a 20-mesh sieve to obtain chitosan-iron-manganese-based modified montmorillonite (CTS@Fe-Mn-Mt);

[0068] 2. Preparation of modified zeolite

[0069] (1) washing 1 kg of zeolite with deionized water until the pH of the washing solution is 7, freeze-drying the washed zeolite, crushing and grinding it, and then passing it through a 20-mesh sieve to obtain purified zeolite;

[0070] (2) The purified zeolite obtained in step (1) is immersed in a hydrochloric acid solution for modification for 2 h, wherein the concentration of the hydrochloric acid is 0.3 mol / L and the volume is 10 L. Thereafter, the immersed and modified zeolite is freeze-dried, crushed and ground, and then passed through a 20-mesh sieve to obtain a hydrochloric acid-modified zeolite (HCl-Z);

[0071] (3) The hydrochloric acid modified zeolite obtained in step (2) is immersed in a calcium chloride solution for modification for 20 minutes, wherein the concentration of the calcium chloride solution is 1 mol / L and the volume is 10 L. After that, the immersed and modified zeolite is freeze-dried, crushed and ground, and then passed through a 20-mesh sieve to obtain a calcium chloride hydrochloric acid modified zeolite (CaCl2-HCl-Z);

[0072] 3. Preparation of organic fertilizer based on vinegar residue

[0073] (1) crushing 1 kg of vinegar dregs and mixing them with 0.5 kg of livestock and poultry feces, drying them to a moisture content of 50 wt%, then adding 0.15 kg of feces fermentation agent, and fermenting them at 30° C. for 10 days to obtain a fermentation product;

[0074] (2) The fermentation product prepared in step (1) was mixed with 0.5 kg of the modified montmorillonite prepared in step 1 and 0.5 kg of the modified zeolite prepared in step 2, and the mixture was fermented at 60° C. for 1 day, and then 0.25 kg of humic acid was added and stirred for 2 hours to prepare an organic fertilizer based on vinegar lees.

[0075] Comparative Example 1

[0076] The same as Example 1, except that the modification of montmorillonite in step 1 is omitted, and step (2) in step 3 is to mix the fermentation product prepared in step (1) with 20 kg of natural montmorillonite and 20 kg of modified zeolite prepared in step 2, and continue fermenting at 80° C. for 2 days, then add 10 kg of humic acid, stir for 3 hours, and prepare an organic fertilizer based on vinegar lees.

[0077] Comparative Example 2

[0078] The same as Example 1, except that the modification of the zeolite in step 2 is omitted, and step (2) in step 3 is to mix the fermentation product prepared in step (1) with 20 kg of modified montmorillonite in step 1 and 20 kg of natural zeolite, and continue fermenting at 80° C. for 2 days, then add 10 kg of humic acid, stir for 3 hours, and prepare an organic fertilizer based on vinegar lees.

[0079] Comparative Example 3

[0080] Same as Example 1, except that: the preparation method of modified montmorillonite in step 1 is:

[0081] (1) washing 1 kg of montmorillonite with deionized water until the pH of the washing solution is 7, freeze-drying the washed montmorillonite, crushing and grinding it, and then passing it through a 20-mesh sieve to obtain purified montmorillonite;

[0082] (2) The purified montmorillonite obtained in step (1) is immersed in a mixed solution of ferric chloride and manganese chloride for modification for 30 minutes, wherein the concentration of ferric chloride is 3 mol / L and the volume is 10 L, and the concentration of manganese chloride is 3 mol / L and the volume is 10 L; then the immersed modified montmorillonite is washed with deionized water until the pH of the washing solution is 7, and the washed montmorillonite is freeze-dried, crushed and ground, and then passed through a 20-mesh sieve to obtain iron-manganese-based modified montmorillonite (Fe-Mn-Mt).

[0083] Comparative Example 4

[0084] Same as Example 1, except that: the preparation method of modified montmorillonite in step 1 is:

[0085] (1) washing 1 kg of montmorillonite with deionized water until the pH of the washing solution is 7, freeze-drying the washed montmorillonite, crushing and grinding it, and then passing it through a 20-mesh sieve to obtain purified montmorillonite;

[0086] (2) 3 kg of chitosan was mixed with 10 L of 1 vol.% acetic acid solution and stirred at 60° C. for 2.5 h to obtain an acetic acid solution of chitosan;

[0087] (3) The purified montmorillonite obtained in step (1) is placed in 30 L of deionized water, stirred at 50° C. for 60 min, and then the acetic acid solution of chitosan prepared in step (2) is slowly added within 10 min, and stirring is continued for 20 min. The chitosan-modified montmorillonite is then freeze-dried, crushed and ground, and then passed through a 20-mesh sieve to obtain chitosan-modified montmorillonite (CTS@Mt).

[0088] Comparative Example 5

[0089] Same as Example 1, except that: the preparation method of modified montmorillonite in step 1 is:

[0090] (1) washing 1 kg of montmorillonite with deionized water until the pH of the washing solution is 7, freeze-drying the washed montmorillonite, crushing and grinding it, and then passing it through a 20-mesh sieve to obtain purified montmorillonite;

[0091] (2) 3 kg of chitosan was mixed with 10 L of 1 vol.% acetic acid solution and stirred at 60° C. for 2.5 h to obtain an acetic acid solution of chitosan;

[0092] (3) placing the purified montmorillonite obtained in step (1) in 30 L of deionized water, mixing and stirring at 50° C. for 60 min, then adding the chitosan acetic acid solution prepared in step (2), stirring at 50° C. for 20 min, then freeze-drying the purified montmorillonite modified with chitosan, crushing and grinding it, and then passing it through a 20-mesh sieve to obtain chitosan-modified montmorillonite (CTS@Mt);

[0093] (4) The CTS@Mt obtained in step (3) was immersed in a mixed solution of ferric chloride and manganese chloride for 30 minutes, wherein the concentration of ferric chloride was 3 mol / L and the volume was 10 L, and the concentration of manganese chloride was 3 mol / L and the volume was 10 L; then, the immersed modified CTS@Mt was washed with deionized water until the pH of the washing solution was 7, and the washed montmorillonite was freeze-dried, crushed and ground, and then passed through a 20-mesh sieve to obtain chitosan-iron manganese-based modified montmorillonite (CTS@Fe-Mn-Mt).

[0094] Comparative Example 6

[0095] Same as Example 1, except that: in the preparation method of modified montmorillonite in step 1:

[0096] Step (2) is to immerse the purified montmorillonite obtained in step (1) in a ferric chloride solution for modification for 30 minutes, wherein the concentration of the ferric chloride is 3 mol / L and the volume is 20 L; then the impregnated modified montmorillonite is washed with deionized water until the pH of the washing solution is 7, and the washed montmorillonite is freeze-dried, crushed and ground, and then passed through a 20-mesh sieve to obtain iron-based modified montmorillonite (Fe-Mt).

[0097] Comparative Example 7

[0098] Same as Example 1, except that: in the preparation method of modified montmorillonite in step 1:

[0099] Step (2) is to immerse the purified montmorillonite obtained in step (1) in a manganese chloride solution for modification for 30 minutes, wherein the concentration of manganese chloride is 3 mol / L and the volume is 20 L; then the impregnated modified montmorillonite is washed with deionized water until the pH of the washing solution is 7, and the washed montmorillonite is freeze-dried, crushed and ground, and then passed through a 20-mesh sieve to obtain manganese-based modified montmorillonite (Mn-Mt).

[0100] Comparative Example 8

[0101] Same as Example 1, except that: in the preparation method of modified montmorillonite in step 1:

[0102] Step (2) is to immerse the purified montmorillonite obtained in step (1) in a mixed solution of sodium chloride and manganese chloride for modification for 30 minutes, wherein the concentration of sodium chloride is 3 mol / L and the volume is 10 L, and the concentration of manganese chloride is 3 mol / L and the volume is 10 L; then, the impregnated modified montmorillonite is washed with deionized water until the pH of the washing solution is 7, and the washed montmorillonite is freeze-dried, crushed and ground, and then passed through a 20-mesh sieve to obtain sodium manganese-based modified montmorillonite (Na-Mn-Mt).

[0103] Comparative Example 9

[0104] Same as Example 1, except that: in the preparation method of modified montmorillonite in step 1:

[0105] Step (3) is to mix 3 kg of cellulose with 10 L of 1 vol.% acetic acid solution, and stir at 60° C. for 2.5 h to obtain a cellulose solution;

[0106] Step (4) is to place the Fe-Mn-Mt obtained in step (2) in 30L of deionized water, stir at 50°C for 60 minutes, then slowly add the cellulose solution prepared in step (3) within 10 minutes, continue stirring for 20 minutes, and then freeze-dry, crush and grind the chitosan-modified Fe-Mn-Mt and pass it through a 20-mesh sieve to obtain cellulose-iron-manganese-based modified montmorillonite (CA@Fe-Mn-Mt).

[0107] Comparative Example 10

[0108] Same as Example 1, except that: the preparation method of the modified zeolite in step 2 is:

[0109] (1) washing 1 kg of zeolite with deionized water until the pH of the washing solution is 7, freeze-drying the washed zeolite, crushing and grinding it, and then passing it through a 20-mesh sieve to obtain purified zeolite;

[0110] (2) The purified zeolite obtained in step (1) is immersed in a calcium chloride solution for modification for 30 minutes, wherein the concentration of the calcium chloride solution is 3 mol / L and the volume is 20 L. Thereafter, the immersed and modified zeolite is freeze-dried, crushed and ground, and then passed through a 20-mesh sieve to obtain a calcium chloride-modified zeolite (CaCl2-Z).

[0111] Comparative Example 11

[0112] Same as Example 1, except that: the preparation method of the modified zeolite in step 2 is:

[0113] (1) washing 1 kg of zeolite with deionized water until the pH of the washing solution is 7, freeze-drying the washed zeolite, crushing and grinding it, and then passing it through a 20-mesh sieve to obtain purified zeolite;

[0114] (2) The purified zeolite obtained in step (1) is immersed in a hydrochloric acid solution for modification for 3 h, wherein the concentration of the hydrochloric acid is 0.5 mol / L and the volume is 20 L. Thereafter, the immersed and modified zeolite is freeze-dried, crushed and ground, and then passed through a 20-mesh sieve to obtain a hydrochloric acid-modified zeolite (HCl-Z).

[0115] Comparative Example 12

[0116] Same as Example 1, except that: the preparation method of the modified zeolite in step 2 is:

[0117] (1) washing 1 kg of zeolite with deionized water until the pH of the washing solution is 7, freeze-drying the washed zeolite, crushing and grinding it, and then passing it through a 20-mesh sieve to obtain purified zeolite;

[0118] (2) The purified zeolite obtained in step (1) is immersed in a calcium chloride solution for modification for 30 minutes, wherein the concentration of the calcium chloride solution is 1.5 mol / L and the volume is 20 L. Thereafter, the immersed and modified zeolite is freeze-dried, crushed and ground, and then passed through a 20-mesh sieve to obtain a calcium chloride-modified zeolite (CaCl2-Z).

[0119] (3) The calcium chloride modified zeolite obtained in step (1) is immersed in a hydrochloric acid solution for modification for 3 hours, wherein the concentration of the hydrochloric acid is 0.5 mol / L and the volume is 20 L. Thereafter, the immersed and modified zeolite is freeze-dried, crushed and ground, and then passed through a 20-mesh sieve to obtain a calcium chloride hydrochloric acid modified zeolite (CaCl2-HCl-Z).

[0120] Comparative Example 13

[0121] Same as Example 1, except that: in the preparation process of modified zeolite in step 2,

[0122] Step (2) is to immerse and modify the purified zeolite obtained in step (1) in a sulfuric acid solution for 3 hours, wherein the concentration of the sulfuric acid is 0.5 mol / L and the volume is 20 L, and then the impregnated and modified zeolite is freeze-dried, crushed and ground, and then passed through a 20-mesh sieve to obtain sulfuric acid-modified zeolite (H2SO4-Z);

[0123] Step (3) is to immerse the sulfuric acid-modified zeolite obtained in step (2) in a calcium chloride solution for modification for 30 minutes, wherein the concentration of the calcium chloride solution is 1.5 mol / L and the volume is 20 L. After that, the impregnated and modified zeolite is freeze-dried, crushed and ground, and then passed through a 20-mesh sieve to obtain calcium chloride sulfuric acid-modified zeolite (CaCl2-H2SO4-Z).

[0124] Comparative Example 14

[0125] Same as Example 1, except that: in the preparation process of modified zeolite in step 2,

[0126] Step (3) is to immerse the hydrochloric acid modified zeolite obtained in step (2) in a sodium chloride solution for modification for 30 minutes, wherein the concentration of the sodium chloride solution is 1.5 mol / L and the volume is 20 L. After that, the impregnated and modified zeolite is freeze-dried, crushed and ground, and then passed through a 20-mesh sieve to obtain sodium chloride hydrochloric acid modified zeolite (NaCl-HCl-Z).

[0127] Comparative Example 15

[0128] The same as Example 1, except that in step 3, in the preparation of organic fertilizer based on vinegar grains, the humic acid in step (2) is omitted.

[0129] Effect verification:

[0130] 1. Fertility test

[0131] The fertility test was performed on the organic fertilizers prepared in Examples 1 to 3 and Comparative Examples 1 to 15. The specific test methods refer to the "National Standards for Organic Fertilizers and Test Methods for Various Indicators". The specific test results are shown in Table 1.

[0132] Table 1 Fertility determination

[0133] Organic matter (%) Fecal coliform count (unit / g) Total nutrient mass fraction (%) Example 1 75 5 18 Example 2 73 6 17 Example 3 72 6 16 Comparative Example 1 55 15 9 Comparative Example 2 56 14 11 Comparative Example 3 63 11 12 Comparative Example 4 65 10 10 Comparative Example 5 72 7 15 Comparative Example 6 68 9 13 Comparative Example 7 69 7 12 Comparative Example 8 70 7 14 Comparative Example 9 68 8 14 Comparative Example 10 58 13 10 Comparative Example 11 60 10 9 Comparative Example 12 71 6 14 Comparative Example 13 71 8 12 Comparative Example 14 70 6 15 Comparative Example 15 70 10 15

[0134] 2. Determination of heavy metal content in soil

[0135] Heavy metal contaminated agricultural soil (dry land, 5.5 < pH ≤ 6.5) was placed in 13 identical containers, and then the organic fertilizers prepared in Examples 1 to 3 and Comparative Examples 1 to 15 were applied according to 5% of the weight of the soil, and the soil moisture was kept at 30 to 40%. Soil samples were collected after 30 days, and the heavy metal content was determined according to GB 15618-2018 "Soil Environmental Quality Agricultural Land Soil Pollution Risk Control Standard (Trial)", and the specific measurement results are shown in Table 2;

[0136] Table 2 Heavy metal content in soil

[0137]

[0138] 3. Determination of cadmium content in crops after application of organic fertilizers to soil

[0139] Complete, healthy and full wheat seeds were taken and sown in the soil after the treatment of effect verification 2, 30 seeds were sown in each container, and the sowing depth was 2 cm; the container was placed in an intelligent artificial climate plant box for cultivation, the daytime temperature was 25±2°C, full light, the night temperature was 18±2°C, dark, the humidity was 60-70% throughout the day, and watering was done every other day; after one week of growth, the seedlings were thinned out, 15 seedlings were left in each container, and the roots of the wheat plants were collected after 30 days of growth, and the cadmium content in the roots of the wheat plants was determined by graphite furnace atomic absorption spectrophotometry, and the specific results are shown in Table 3;

[0140] Table 3 Cadmium content in roots of wheat plants

[0141] Cadmium (mg / kg) Heavy metal contaminated soil 0.50 Example 1 0.03 Example 2 0.04 Example 3 0.04 Comparative Example 1 0.31 Comparative Example 2 0.31 Comparative Example 3 0.16 Comparative Example 4 0.10 Comparative Example 5 0.05 Comparative Example 6 0.08 Comparative Example 7 0.07 Comparative Example 8 0.06 Comparative Example 9 0.10 Comparative Example 10 0.23 Comparative Example 11 0.17 Comparative Example 12 0.04 Comparative Example 13 0.07 Comparative Example 14 0.07 Comparative Example 15 0.09

[0142] The above description is only a preferred specific implementation manner of the present invention, and the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, and they should be covered by the protection scope of the present invention.

Claims

1. An organic fertilizer based on vinegar lees, characterized in that: The invention comprises the following raw materials in parts by weight: The preparation method of the modified montmorillonite is: (1) washing the montmorillonite with water until the pH of the washing solution is 7 to obtain purified montmorillonite; (2) The purified montmorillonite obtained in step (1) is modified by immersing it in a mixed solution of ferric chloride and manganese chloride, and then washed with water until the pH of the washing solution is 7, thereby obtaining an iron-manganese-based modified montmorillonite; (3) mixing the iron-manganese-based modified montmorillonite obtained in step (2) with water, and then adding chitosan and stirring to obtain chitosan-iron-manganese-based modified montmorillonite, i.e., the modified montmorillonite; In step (2) of the preparation method of the modified montmorillonite, the preparation method of the mixed solution of ferric chloride and manganese chloride is: mixing a ferric chloride solution with a concentration of 2 to 3 mol / L with a manganese chloride solution with a concentration of 2 to 3 mol / L, wherein the mass volume ratio of the montmorillonite, the ferric chloride solution and the manganese chloride solution is 1 kg: (5 to 10) L: (5 to 10) L; the time of the impregnation modification is 20 to 30 min; In step (3) of the preparation method of the modified montmorillonite, the chitosan is an acetic acid solution of chitosan. The specific preparation method is: dissolving chitosan in 1 vol% acetic acid, the mass volume ratio of chitosan to acetic acid is (2-3) kg:10 L; the mass volume ratio of the iron-manganese-based modified montmorillonite, chitosan, and water is 1 kg: (2-3) kg: (20-30) L; the mixing temperature is 30-50°C, and the time is 30-60 min; the mixing temperature is 30-50°C, and the time is 10-20 min; The preparation method of the modified zeolite is: (1) washing the zeolite with water until the pH of the washing solution is 7 to obtain purified zeolite; (2) The purified zeolite obtained in step (1) is modified by immersing in a hydrochloric acid solution, and then washed with water until the pH of the washing solution is 7, to obtain a hydrochloric acid modified zeolite; (3) The hydrochloric acid modified zeolite obtained in step (2) is immersed in a calcium chloride solution for modification, and then washed with water until the pH of the washing solution is 7, to obtain calcium chloride-hydrochloric acid modified zeolite, i.e., the modified zeolite; In step (2) of the preparation method of the modified zeolite, the concentration of the hydrochloric acid solution is 0.3-0.5 mol / L, the mass volume ratio of the purified zeolite to the hydrochloric acid solution is 1 kg: (10-20) L, and the immersion modification time is 2-3 h; In step (3) of the preparation method of the modified zeolite, the concentration of the calcium chloride solution is 1-1.5 mol / L, the mass volume ratio of the hydrochloric acid modified zeolite to the calcium chloride solution is 1 kg: (10-20) L; and the immersion modification time is 20-30 min.

2. A method for preparing organic fertilizer based on vinegar grains according to claim 1, characterized in that: The following steps are involved: (1) Mixing vinegar dregs with livestock and poultry manure, drying until the moisture content is 50-60 wt%, adding a manure fermentation agent for fermentation, and obtaining a fermentation product; (2) The fermentation product obtained in step (1) is mixed with modified montmorillonite and modified zeolite, and subjected to secondary fermentation, followed by adding humic acid to obtain the organic fertilizer based on vinegar grains.

3. The preparation method according to claim 2, characterized in that In step (1), the fermentation temperature is 30-40°C and the fermentation time is 10-15 days; in step (2), the secondary fermentation temperature is 60-80°C and the fermentation time is 1-2 days.

4. Use of the vinegar lees-based organic fertilizer according to claim 1 in improving soil fertility and inhibiting heavy metal adsorption by plants.

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