CN111187116A - Preparation and application of straw sustained-release agent - Google Patents
Preparation and application of straw sustained-release agent Download PDFInfo
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- CN111187116A CN111187116A CN202010089078.0A CN202010089078A CN111187116A CN 111187116 A CN111187116 A CN 111187116A CN 202010089078 A CN202010089078 A CN 202010089078A CN 111187116 A CN111187116 A CN 111187116A
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- straw
- release agent
- straw powder
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- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05C—NITROGENOUS FERTILISERS
- C05C9/00—Fertilisers containing urea or urea compounds
-
- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
- A01N25/00—Biocides, pest repellants or attractants, or plant growth regulators, characterised by their forms, or by their non-active ingredients or by their methods of application, e.g. seed treatment or sequential application; Substances for reducing the noxious effect of the active ingredients to organisms other than pests
- A01N25/08—Biocides, pest repellants or attractants, or plant growth regulators, characterised by their forms, or by their non-active ingredients or by their methods of application, e.g. seed treatment or sequential application; Substances for reducing the noxious effect of the active ingredients to organisms other than pests containing solids as carriers or diluents
-
- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
- C05G3/00—Mixtures of one or more fertilisers with additives not having a specially fertilising activity
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- Life Sciences & Earth Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Pest Control & Pesticides (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Toxicology (AREA)
- Plant Pathology (AREA)
- Agronomy & Crop Science (AREA)
- Engineering & Computer Science (AREA)
- Dentistry (AREA)
- Wood Science & Technology (AREA)
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- Environmental Sciences (AREA)
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Abstract
The invention belongs to the field of comprehensive utilization of agricultural wastes, and particularly relates to preparation and application of a straw slow-release agent. The preparation method of the straw slow-release agent provided by the invention comprises the following steps: 1) drying, removing impurities and crushing straws to obtain straw powder; 2) preparing chemical substances into chemical solution with a certain concentration, and then mixing and stirring the straw powder prepared in the step (1) and the chemical solution according to a certain material-liquid ratio; 3) and fishing out or filtering the straw powder, and airing for more than 48 hours to dry the straw powder to obtain the straw slow-release agent. The straw slow-release agent prepared by the invention has good slow-release effect, simple preparation method and very convenient actual use. The pesticide or fertilizer can be added according to actual requirements, and the compound pesticide and fertilizer can be compounded for flexible application.
Description
This application will likely serve as a priority basis for subsequent patent applications (including, but not limited to, chinese invention patent applications, chinese utility model applications, PCT applications, foreign applications based on the paris convention).
Technical Field
The invention belongs to the field of comprehensive utilization of agricultural wastes, and particularly relates to preparation and application of a straw slow-release agent.
Background
China is a big agricultural country, and in the agricultural production process, a large amount of pesticide and fertilizer is used, and the utilization rate is too low, so that a large amount of pesticide and fertilizer is lost outside farmlands, soil caking, pollution to surface water, rivers and lake water are caused, quality indexes such as color, taste and taste of agricultural products are reduced, and even human health is affected in severe cases. Therefore, how to enhance the holding ability of nitrogen and phosphorus and improve the utilization rate of nitrogen and phosphorus in farmland is always an important problem in the field of environmental protection.
The crop straw is a natural polymer resource with huge quantity and continuous output along with agricultural production, and the volume is huge. The straws of a large number of crops such as corn, rice, wheat and the like generated in China every year are up to 7 hundred million tons. But the comprehensive utilization rate of straw resources is still low, and how to reasonably utilize renewable straw cellulose resources is an important content of the current environment green technology and is also one of the key points of the research work in the field of current resource development and ecological environment protection.
The straw has the characteristics of environmental friendliness and the like, and can be used as a slow-release pesticide and/or fertilizer carrier. A document named as 'preparation of rice straw carbon-based slow release fertilizer and performance research' is taken as the prior art close to the invention, and discloses a straw slow release fertilizer. However, in order to achieve a better slow release effect, carbonized straws are adopted in the document, so that the process is complex and the preparation cost is high.
Disclosure of Invention
In view of the above, one of the objectives of the present invention is to provide a method for preparing a straw sustained release agent. Different from the preparation method of carbonizing the straws in the prior art, the straw sustained-release agent provided by the invention is prepared by directly crushing the straws without carbonization, so that a large amount of cost can be saved, and the straw sustained-release agent is more environment-friendly. Meanwhile, the straw slow-release agent prepared by the method has a good slow-release effect on common pesticides in the market, so that the straw slow-release agent has a larger breakthrough and a potential economic value compared with the prior art.
In order to achieve the purpose, the technical scheme of the invention is as follows:
a preparation method of a straw slow-release agent comprises the following steps:
1) preparing straw powder: drying, removing impurities and crushing plant straws to obtain straw powder with the particle size of 50-300 meshes;
2) soaking chemical substances: preparing chemical substances into an aqueous solution with the concentration of 1% -10%, and mixing the straw powder prepared in the step 1) and the chemical substance aqueous solution according to the material-liquid ratio of 1:10-1:30, so that all the straw powder is immersed by the solution and stirred for no less than 24 hours;
3) drying straws: and fishing out or filtering the straw powder adsorbed with the chemical substances, and airing the straw powder in a shade for more than 48 hours to dry the straw powder to obtain the straw sustained-release agent.
Further, the particle size range of the straw powder is 80-200 meshes.
Further, the feed-liquid ratio of the straw powder to the pesticide or fertilizer aqueous solution is 1: 20.
Further, the chemical substance is a pesticide or a fertilizer.
Further, the pesticide or fertilizer comprises one or more of urea, diammonium phosphate, ammonium phosphate phosphorus, carbendazim, malathion or difenoconazole.
Further, the stirring speed in the step 2) is 10-100 r/min.
Further, the concentration of the chemical substance aqueous solution is 1%.
The invention also aims to provide a novel slow-release fertilizer and application thereof.
The straw slow-release agent prepared by the preparation method.
The straw slow-release agent can be applied to the yield increase of economic crops, grain crops, vegetables, fruit trees or flowers.
Experiments show that the straw powder has large surface area, more pores and hydrophobic surface, and pesticides and fertilizers as hydrophobic substances are easily adsorbed on the surface of the straw with strong hydrophobicity. Secondly, as the straw powder is degraded by flora in soil, the protein, hemicellulose and lignin in the composition are gradually degraded, wherein part of cellulose is continuously retained in the soil due to the formation of cellulose crystals. In earlier researches, the invention discovers that the adsorption capacity of the straw powder to various pesticides or chemical fertilizers is far stronger than that of cellulose crystals, so that the degraded straw powder further releases the adsorbed pesticides or chemical fertilizers to play a slow-release role.
The invention also aims to provide a using method of the slow-release pesticide.
The application method of the straw slow-release agent comprises the steps of turning the straw slow-release agent into soil, enabling the distance between the straw slow-release agent and the surface layer of the soil to be 10-30cm, and planting crops in the soil.
Further, the distance between the straw slow-release agent and the surface layer of the soil is 20 cm. The length of the roots of common crops such as vegetables, fruits and the like is about 20cm, so that the straw slow-release agent can achieve better effect when being applied to the soil deeply.
The invention has the beneficial effects
The preparation method of the straw sustained-release agent provided by the invention is simple and is very convenient in actual use. The composite pesticide and fertilizer can be added according to actual requirements, can be compounded into a composite pesticide and fertilizer, can be flexibly applied, improves the additional value of straw application, expands a new idea of straw resource utilization, and has good application prospects in agriculture and horticulture.
The straw slow-release agent prepared by the method has the advantage of slow release, for example, the preparation method of the straw slow-release agent provided by the invention has a good slow release effect on common pesticides. The slow release of pesticide such as glyphosate, Dimethoate and the like can be realized for more than 45 days, and the slow release of common pesticide such as urea and the like can be realized for more than 40 days. Therefore, the invention can effectively improve the utilization rate of the pesticide and the fertilizer in the farmland and is more friendly to the ecological environment.
The straw sustained-release agent prepared by the preparation method has good sustained-release effect, not only because the straw powder prepared by the invention is returned to the field, but also the adsorbed pesticide or fertilizer is continuously released along with the dynamic balance in the soil; moreover, as the straw powder is degraded by the flora in the soil, the protein, hemicellulose and lignin in the composition are gradually degraded, and part of cellulose is continuously remained in the soil due to formed cellulose crystals, but because the adsorption capacity of the cellulose crystals to various pesticides and fertilizers is very weak, the pesticides and fertilizers are further gradually released in the formation process of the cellulose crystals, so that the slow release effect is improved.
Drawings
FIG. 1 is the scanning electron microscope image of 4 substances (aged micro-plastic (a), microcrystalline cellulose (b), wheat straw powder (c) and wheat straw segment (d); scale is 10 um).
FIG. 2 is a fitting parameter of a quasi-first order kinetic equation, a quasi-second order kinetic and a particle diffusion model for pesticide adsorption on straw cellulose crystals.
FIG. 3 is a fitting parameter of a quasi-first order kinetic equation, a quasi-second order kinetic and particle diffusion model for the adsorption of a pesticide on wheat straw powder.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. It is to be understood that the embodiments described are only a few embodiments of the present invention, and not all 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.
The examples are given for the purpose of better illustration of the invention, but the invention is not limited to the examples. Therefore, those skilled in the art should make insubstantial modifications and adaptations to the embodiments of the present invention in light of the above teachings and remain within the scope of the invention.
Unless otherwise specified, the terms "comprise" and "comprise," as well as grammatical variations thereof, are used to denote "open" or "including" language such that they include the recited features but also allow for the inclusion of additional, non-recited features.
As used in this specification, the term "about" typically means +/-5% of the stated value, more typically +/-4% of the stated value, more typically +/-3% of the stated value, more typically +/-2% of the stated value, even more typically +/-1% of the stated value, and even more typically +/-0.5% of the stated value.
In this specification, certain embodiments may be disclosed in a range of formats. It should be understood that this description of "within a certain range" is merely for convenience and brevity and should not be construed as an inflexible limitation on the scope of the disclosure. Accordingly, the description of a range should be considered to have specifically disclosed all possible subranges as well as individual numerical values within that range (e.g., a particle size range of the straw powder of 80-200 mesh). For example, the description of the range 1-6 should be read as having specifically disclosed sub-ranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as individual numbers within this range, such as 1, 2, 3, 4, 5, and 6. The above rules apply regardless of the breadth of the range.
Example 1
(1) Preparing straw powder: drying straw (from plants such as corn, rice, wheat, etc.), removing impurities, and pulverizing to obtain straw powder with particle size of 50-300 mesh.
(2) Soaking of the fertilizer: dissolving urea in water to prepare a 10% solution, soaking the prepared straw powder in a solution of the chemical fertilizer according to the ratio of the material to the liquid of 1:10, uniformly stirring to immerse all the straw powder in the solution, and continuously and slowly stirring for not less than 24 hours to enable the chemical fertilizer to be well adsorbed on the straw powder.
(3) Airing the straws: and fishing out or filtering the straw powder adsorbed with the fertilizer, and airing the straw powder in a shade for at least 48 hours to dry the straw powder.
(4) Returning the straws to the field: and (4) turning the aired straws into the soil, wherein the distances between the aired straws and the surface layer of the soil are 10cm, and planting crops in the soil.
Example 2
(1) Preparing straw powder: drying, removing impurities and crushing plant straws to obtain straw powder with the particle size of 80-200 meshes.
(2) Soaking of the fertilizer: dissolving urea in water to prepare a 1% solution, soaking the prepared straw powder in a solution of the chemical fertilizer according to the ratio of the material to the liquid of 1:20, uniformly stirring to immerse all the straw powder in the solution, and continuously and slowly stirring for not less than 24 hours to enable the chemical fertilizer to be well adsorbed on the straw powder.
(3) Airing the straws: and fishing out or filtering the straw powder adsorbed with the fertilizer, and airing the straw powder in a shade for at least 48 hours to dry the straw powder.
(4) Returning the straws to the field: and (4) turning the aired straws into the soil, wherein the aired straws are 20cm deep from the surface layer of the soil, and planting crops in the soil.
Example 3
(1) Preparing straw powder: drying, removing impurities and crushing plant straws to obtain straw powder with the particle size of 80-200 meshes.
(2) Soaking of the fertilizer: dissolving urea in water to prepare a 5% solution, soaking the prepared straw powder in a chemical fertilizer solution according to the ratio of the material to the liquid being 1:30, uniformly stirring to immerse all the straw powder in the solution, and continuously and slowly stirring for not less than 24 hours to enable the chemical fertilizer to be well adsorbed on the straw powder.
(3) Airing the straws: and fishing out or filtering the straw powder adsorbed with the fertilizer, and airing the straw powder in a shade for at least 48 hours to dry the straw powder.
(4) Returning the straws to the field: and (4) turning the aired straws into the soil, wherein the distances between the aired straws and the surface layer of the soil are 30cm, and planting crops in the soil.
Example 4
The pesticide urea and 30% glyphosate solution and dimethoate were added as described above in examples 1-3. Urea, 30% glyphosate and dimethoate are respectively prepared into 1% aqueous solution.
The prepared slow-release pesticide is turned into soil, the depth of the slow-release pesticide is 20cm from the surface layer of the soil, and crops are planted in the soil.
The soil was used as an experimental subject, and the soil was sampled every 5 days and tested for pesticides.
The experimental results are as follows: glyphosate molecules and dimethoate molecules can still be detected after 45 days. The urea molecules were still detectable after 40 days.
Example 5
Scanning electron micrographs of the aged micro-plastic, microcrystalline cellulose, wheat straw powder and wheat straw segments were collected, respectively, as shown in fig. 1. As is clear from the figure, the aged plastic has a non-uniform surface roughness and many layer structures, lamellar structures and cracks. The microcrystalline cellulose is approximately in a rod-shaped structure, and transverse lines on the surface of the cellulose are obvious and are accompanied by micropores with different sizes. The inner tangent plane of the wheat straw section is provided with a large number of reticular micropores. Compared with the wheat straw segments, the net structure of the wheat straw powder is destroyed in the crushing process, and the specific surface area of the wheat straw powder is increased.
Kinetics study of adsorbed pesticide
The invention detects 4 kinds of pesticides, namely Carbendazim (CAR), Diflubenzuron (DIF), Malathion (Malathion, MAL), Difenoconazole (Difenoconazole, DIFE, the first-order kinetic equation, the second-order kinetic equation and the particle diffusion model fitting parameters absorbed on 2 kinds of straw degradation products, and the parameters are shown in table 1 and figures 2 and 3.
The experiment of pesticide adsorption kinetics is carried out by using 10ml centrifuge tubes, 5ml of 1 mg/L4 pesticide mixed liquid is added into each centrifuge tube, and 50mg of adsorbate sample is added at the same time. Shaking at 25 deg.C and 180rpm for 0, 10, 20, 30, 40, 50, 60, 80, 100, 120, and 240min, centrifuging at 10000rpm for 5min, filtering with 0.22um filter membrane, and detecting. 50mg of each adsorbate was added to 5ml of 5% acetonitrile water as a blank. Three replicates were set for each sample and averaged. The adsorbate is wheat straw powder and straw cellulose crystal.
TABLE 1
It can be seen from the table that the adsorption process of 4 pesticides on 2 straw degradation products better satisfies the quasi-second order kinetics equation, and from the equilibrium adsorption Qe, the adsorption amount of the wheat straw powder is obviously greater than that of the straw cellulose crystals except for diflubenzuron.
While the present invention has been described with reference to the embodiments shown in the drawings, the present invention is not limited to the embodiments, which are illustrative and not restrictive, and it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (10)
1. A preparation method of a straw slow-release agent is characterized by comprising the following steps:
(1) drying, impurity removing and crushing straws to obtain straw powder, wherein the particle size range of the straw powder is 50-300 meshes;
(2) preparing chemical substances into a chemical solution with the concentration of 1% -10%, and then uniformly mixing the straw powder prepared in the step (1) and the chemical solution according to the material-liquid ratio of 1:10-1:30, so that the straw powder is immersed in the chemical solution, and stirring for not less than 24 hours;
(3) and fishing out or filtering the straw powder, and airing for more than 48 hours to dry the straw powder to obtain the straw slow-release agent.
2. The method of claim 1, wherein the straw powder has a particle size in the range of 80-200 mesh.
3. The preparation method of claim 1, wherein the feed-to-liquid ratio of the straw powder to the chemical substance is 1: 20.
4. The method of claim 1, wherein the chemical is a pesticide or a fertilizer.
5. The method of claim 4, wherein the pesticide or fertilizer comprises one or more of urea, diammonium phosphate, phosphorus ammonium nitrate, carbendazim, malathion, or difenoconazole.
6. The method according to claim 1, wherein the stirring in the step (2) is carried out at a rate of 10 to 100 r/min.
7. The method of claim 1, wherein the chemical solution has a concentration of 1% of the chemical species.
8. A straw sustained-release agent prepared by the method of any one of claims 1 to 7.
9. The use of the straw sustained-release agent in crop yield increase according to claim 8, wherein the straw sustained-release agent can be used for the yield increase of cash crops, food crops, vegetables, fruit trees and/or flowers.
10. The use method of the straw slow-release agent as claimed in claim 8, wherein the straw slow-release agent is turned into soil at a distance of 10-30cm from the surface layer of the soil.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010089078.0A CN111187116A (en) | 2020-02-12 | 2020-02-12 | Preparation and application of straw sustained-release agent |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010089078.0A CN111187116A (en) | 2020-02-12 | 2020-02-12 | Preparation and application of straw sustained-release agent |
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| CN111187116A true CN111187116A (en) | 2020-05-22 |
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| CN202010089078.0A Pending CN111187116A (en) | 2020-02-12 | 2020-02-12 | Preparation and application of straw sustained-release agent |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114907860A (en) * | 2022-06-01 | 2022-08-16 | 中国标准化研究院 | Soil treatment agent and preparation method thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103461325A (en) * | 2013-06-06 | 2013-12-25 | 黄山市迎客松生物科技有限公司 | Straw-based drug liquid controlled release agent and preparation method thereof |
| CN106083372A (en) * | 2016-06-20 | 2016-11-09 | 中国科学院合肥物质科学研究院 | A kind of medium carrier type slow-release carbamide based on straw and preparation method thereof |
| CN106976862A (en) * | 2017-04-17 | 2017-07-25 | 深圳文科园林股份有限公司 | A kind of preparation method of nitrogen phosphorus slow release fertilizer |
-
2020
- 2020-02-12 CN CN202010089078.0A patent/CN111187116A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103461325A (en) * | 2013-06-06 | 2013-12-25 | 黄山市迎客松生物科技有限公司 | Straw-based drug liquid controlled release agent and preparation method thereof |
| CN106083372A (en) * | 2016-06-20 | 2016-11-09 | 中国科学院合肥物质科学研究院 | A kind of medium carrier type slow-release carbamide based on straw and preparation method thereof |
| CN106976862A (en) * | 2017-04-17 | 2017-07-25 | 深圳文科园林股份有限公司 | A kind of preparation method of nitrogen phosphorus slow release fertilizer |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114907860A (en) * | 2022-06-01 | 2022-08-16 | 中国标准化研究院 | Soil treatment agent and preparation method thereof |
| CN114907860B (en) * | 2022-06-01 | 2023-12-01 | 中国标准化研究院 | Soil treatment agent and preparation method thereof |
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Application publication date: 20200522 |