Compound biological stimulant urea, its preparation method and application of biological stimulant

Abstract

The present invention discloses a composite biostimulant urea, its preparation method and the application of the biostimulant. The biostimulant APAA is used for preparing urea. The specific preparation method comprises the following steps: (1) catalytically synthesizing molten urea solution from basic urea raw materials; (2) evaporating the molten urea solution and adding the biostimulant APAA during the evaporation stage to obtain composite granulation raw materials; (3) granulating the composite granulation raw materials to prepare the composite biostimulant urea. By adding the biostimulant APAA to nitrogen fertilizers, the present invention has the functions of stability, growth promotion and stress resistance such as low temperature and salinity, and passivating heavy metals; the added biostimulant APAA is a multi-component biostimulant with a synergistic effect, that is, it improves the utilization rate of nitrogen fertilizers, and at the same time has the effects of promoting the growth, stress resistance and root growth of crops, and conserving water and fertilizer in the soil, achieving the comprehensive regulation effect of fertilizers, crops and soil.

Description

Technical Field

[0001] The present invention belongs to the technical field of fertilizers, and particularly relates to a composite biostimulant urea, its preparation method, and the application of the biostimulant. Background Art

[0002] As an important part of agricultural fertilizers, urea can be applied in various forms such as top dressing during the growth period, slow-release nitrogen fertilizer, compound (mixed) fertilizer, etc., and can also be used as a water-soluble nitrogen fertilizer in integrated water and fertilizer management, capable of supplementing the urgently needed nitrogen nutrition during the critical period of crop growth. However, the nitrogen utilization rate of urea is not high. The main reason is that urea is easily affected by the comprehensive influence of soil microorganisms, enzymes, and chemical substances in the environment, resulting in a situation that does not match the plant's nutritional requirements. Therefore, since 2000, major urea production enterprises have upgraded urea products by adding various synergistic substances. For example, polypeptide urea, value-added urea, humic acid urea, etc. have gradually occupied the main body in the market from occupying a certain position.

[0003] With the in-depth promotion of application, it is found that there are still some drawbacks in these upgraded urea products, such as the synergistic effect is not obvious, the cost performance is relatively low, and the function is single, etc. Summary of the Invention

[0004] The first object of the present invention is to provide an application of a biostimulant APAA.

[0005] The second object of the present invention is to provide a preparation method of a composite biostimulant urea.

[0006] The third object of the present invention is to provide a composite biostimulant urea.

[0007] The first object of the present invention is implemented by the following technical solution: The application of biostimulant polyglutamic acid rhamnolipid (APAA) in the preparation of urea products to improve nitrogen utilization rate.

[0008] The second object of the present invention is implemented by the following technical solution: A preparation method of composite biostimulant urea, which includes the following steps: (1) Catalytically synthesize molten urea solution from basic urea raw materials; (2) Evaporate the molten urea solution and add biostimulant APAA during the evaporation stage to obtain composite granulation raw materials; (3) Granulate the composite granulation raw materials to prepare composite biostimulant urea.

[0009] Specifically, the step (2) specifically includes:

[0010] S1: Obtain a primary urea solution concentrate by primary evaporation;

[0011] S2: Add biostimulant APAA to the primary urea solution concentrate to obtain a composite urea solution concentrate;

[0012] S3: The composite urea liquid concentrate is secondarily concentrated to obtain a composite granulation raw material.

[0013] Specifically, the mass ratio of the biostimulant APAA to the composite biostimulant urea is 1:250 to 1:166.

[0014] The third object of the present invention is implemented by the following technical solution: the composite biostimulant urea prepared by using the preparation method of the composite biostimulant urea described in the second object of the present invention.

[0015] Advantages of the present invention:

[0016] (1) By adding the biostimulant APAA to the nitrogen fertilizer, the present invention has the functions of stabilization, growth promotion, stress resistance such as low temperature and salinity, and passivation of heavy metals.

[0017] (2) In the urea prepared by the present invention, the nitrogen is composed of multiple types. There are both quick-acting ammonium nitrogen and amide nitrogen, and a certain amount of organic nitrogen. Its composition conforms to the demand law of most crops for nitrogen. Therefore, the nitrogen utilization rate is significantly improved.

[0018] (3) The biostimulant APAA added in the present invention is a multi-component biostimulant with a synergistic effect, that is, it improves the utilization rate of nitrogen fertilizer, and at the same time has the effects of promoting the growth, stress resistance and rooting of crops, and maintaining water and fertilizer in the soil, achieving a comprehensive regulation effect on fertilizers, crops and soils. Description of the Drawings

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0020] Figure 1 It is a flow chart of the preparation method of the composite biostimulant urea of the present invention;

[0021] Figure 2 It is the growth situation of corn under different treatments;

[0022] Figure 3 It is a comparison diagram of the growth of the control group CK and the experimental group APAA spinach before low-temperature treatment;

[0023] Figure 4 It is a comparison diagram of the growth of the control group CK and the experimental group APAA spinach after being placed in an environment of 5°C for 72 hours;

[0024] Figure 5It is a comparison chart of the recovery of the Auricularia auricula leaves of the control group CK and the experimental group APAA after being placed in a room temperature environment. Detailed implementation mode

[0025] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

[0026] Example 1: As Figure 1 shown, a preparation method of a composite biological stimulant urea, which includes the following steps:

[0027] (1) Catalytic synthesis of molten urea solution from basic urea raw materials; the basic urea raw materials include liquid ammonia and carbon dioxide; among them, liquid ammonia is obtained by synthesizing ammonia, and carbon dioxide is obtained by purifying the gas production system. The basic urea raw materials are prepared according to the prior art process or directly purchased; in this embodiment, the basic urea raw materials are prepared according to the prior art process. During the production process of urea, the basic urea raw materials, liquid ammonia and carbon dioxide, are catalytically synthesized into molten urea solution in the catalytic tower.

[0028] (2) Evaporating the molten urea solution and adding the biological stimulant APAA in the evaporation stage to obtain composite granulation raw materials: the biological stimulant APAA is purchased from Qingdao Ocean University Biological Group Co., Ltd.

[0029] S1: Obtaining a primary urea solution concentrate by primary evaporation;

[0030] S2: Adding the biological stimulant APAA to the primary urea solution concentrate to obtain a composite urea solution concentrate; in this embodiment, the biological stimulant APAA liquid is added between the first-stage and second-stage evaporators (i.e., the primary and secondary evaporators) at a flow rate of 338.54 kg / h (the flow rate is calculated based on a production system with a standard daily output of 1625 tons of urea), and is mixed and dissolved by relying on the system pressure;

[0031] S3: Secondary concentration of the composite urea solution concentrate to obtain composite granulation raw materials.

[0032] (3) Granulating the composite granulation raw materials to prepare composite biological stimulant urea.

[0033] Processes such as primary evaporation, secondary evaporation, and granulation belong to the prior art and will not be introduced in detail here.

[0034] After detection, the nitrogen content in the prepared compound biostimulant urea is 46.38%, and the moisture content is 0.25%, meeting the requirements of qualified urea in GB2440-2017. The determination of nitrogen content and moisture content is carried out according to the relevant regulations in GB2440-2017 urea.

[0035] Comparative Example 1: The difference from the preparation method of Example 1 is that the biostimulant APAA is replaced with a biostimulant prepared by mixing alginic acid and polyglutamic acid in a mass ratio of 1:1.2, and other treatment methods and parameters are exactly the same as those in Example 1.

[0036] Fertilizer efficiency test 1: Root growth promotion test on corn

[0037] The test treatments are shown in Table 1:

[0038] Table 1 Test treatments

[0039]

[0040] For the test treatments, a 28-6-7 product is selected as the base fertilizer for corn. After sowing the corn, thinning is carried out to ensure consistent and neat growth. During this period, normal watering and weeding management are carried out. When the corn grows to the 6-7 leaf stage (i.e., the large trumpet mouth stage), fertilization is carried out according to the test treatments. For T1, 20 kg / mu of the urea prepared in Comparative Example 1 is used; for T2, 20 kg / mu of the urea prepared in Example 1 is used, and the fertilization amount of T2 is the same as that of T1; for T3, 17 kg / mu of the urea prepared in Example 1 is used (which is 85% of the fertilization amount of the urea prepared in Comparative Example 1, that is, a 15% reduction in fertilizer). Observe the leaf color value, plant height, leaf width, etc. as shown in Figure 2 , and the nitrogen content and leaf area of the leaves are detected as shown in Table 2.

[0041] Test conclusion:

[0042] For different treatments, from the perspective of growth, when applying the urea prepared in Example 1 compared with the urea prepared in Comparative Example 1, the growth of corn is significantly higher, the stems are thicker, and the leaves are larger. The nitrogen content of the leaves in the T2 group is 34.4% higher than that in the T1 group, and the leaf area in the T2 group is 25% higher than that in the T1 group. Comparing the effect of reducing the application amount of the urea prepared in Example 1 by 15% (T3) with the urea prepared in Comparative Example 1 (T1), the effect is significant in terms of leaf width. The nitrogen content of the leaves in the T3 group is 19.7% higher than that in the T1 group, and the leaf area in the T3 group is 18.4% higher than that in the T1 group.

[0043] Table 2: Nitrogen content and leaf area of corn leaves under different treatments

[0044]

[0045] Test 2: Low temperature resistance test

[0046] For the low-temperature resistance test, Basella alba L. was used to simulate a rapidly cooling low-temperature environment, and the growth performance of Basella alba L. under low-temperature conditions was observed. The main observations were the degree of damage caused by foliar fertilizer and the recovery situation after returning to normal temperature conditions, so as to observe the low-temperature resistance effect of the APAA product.

[0047] Table 3 Experimental Treatments (APAA urea, i.e., the urea prepared in Example 1, hereinafter abbreviated as APAA)

[0048]

[0049] Results: Simulating a continuous low-temperature environment, Basella alba L. was placed in a low-temperature environment of 5°C for 72 hours. After taking it out, as Figure 4 shown, most of the leaves in the control group CK had wilted, indicating that they had been damaged by low temperature. For the Basella alba L. treated with APAA in the experimental group, there was a small amount of slight damage at the leaf edges, the damage was not obvious, the leaf surface was slightly wilted, and the leaf surface damage after low temperature was irreversible.

[0050] Continue to place it in a room-temperature environment and observe the leaf recovery situation.

[0051] Results: As Figure 5 shown, the leaves of the control group CK were damaged by frostbite and could not be restored in the adverse environment, and there were still wilted leaves at the leaf edges; for the experimental group APAA, the treated leaves had basically returned to a healthy state.

[0052] Conclusion: APAA can improve the low-temperature resistance of crops. For a sudden temperature drop or continuous low temperature, after spraying or topdressing the APAA product in advance, it can induce the expression of plant stress-resistant genes, improve the low-temperature resistance characteristics of plants, and reduce low-temperature damage.

[0053] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing composite biostimulant urea, characterized in that: The method comprises the following steps: (1) catalyzing the synthesis of molten urea liquid by using a basic urea raw material; (2) evaporating the molten urea liquid and adding a biostimulant polymerized rhamnosyl glutamate during the evaporation stage to obtain a composite granulation raw material; (3) granulating the composite granulation raw material to obtain a composite biostimulant urea; The step (2) specifically includes: S1: one evaporation to obtain a concentrated urea solution; S2: adding the biostimulant polymerized rhamnosyl glutamate to the primary urea concentrate to obtain a composite urea concentrate; S3: The composite urea concentrate is concentrated twice to obtain a composite granulation raw material; The mass ratio of the biostimulant polymerized rhamnosyl glutamate to the composite biostimulant urea is 1:250 to 1:

166.

2. The composite biostimulant urea prepared by the preparation method of the composite biostimulant urea according to claim 1.

Images