Composite biostimulant urea, preparation method thereof and application of biostimulant

Abstract

The invention discloses composite biostimulant urea, a preparation method thereof and application of a biostimulant, the biostimulant APAA is used for preparing urea, and the specific preparation method comprises the following steps: (1) catalytically synthesizing a molten urea solution from a basic urea raw material; (2) evaporating the molten urea liquid, and adding a biostimulant APAA in the evaporation stage to obtain a composite granulation raw material; and (3) granulating the composite granulation raw material to prepare the composite biostimulant urea. By adding the biostimulant APAA into the nitrogen fertilizer, the nitrogen fertilizer has the effects of stabilizing, promoting growth, resisting stress such as low temperature, specific salt and alkali, and passivating heavy metals; the added biogenic stimulant APAA is a multi-element biogenic stimulant and has a synergistic effect, namely, the utilization rate of the nitrogen fertilizer is increased, meanwhile, the effects of promoting growth, resisting stress and rooting are achieved on crops, water and fertilizer are preserved on soil, and the comprehensive regulation and control effect on the fertilizer, the crops and the soil is achieved.

Description

Technical Field

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

[0002] As an important component of agricultural fertilizers, urea can be applied in various forms such as topdressing during the growth period, slow-release nitrogen fertilizer, compound (mixed) fertilizer, etc. It can also be applied as a water-soluble nitrogen fertilizer in water-fertilizer integration, which can supplement the much-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 combined influence of soil microorganisms, enzymes, and chemical substances in the environment, resulting in a mismatch with plant nutritional needs. Therefore, in order to improve the utilization rate of urea nitrogen, since 2000, major urea manufacturers have upgraded urea products by adding a variety of synergistic substances. For example, polypeptide urea, value-added urea, humic acid urea, etc. have gradually occupied the main market from occupying a place.

[0003] As the application and promotion proceed in depth, it is found that these upgraded urea products still have some drawbacks, such as unclear efficiency-enhancing effect, low cost-effectiveness, and single function. 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 method for preparing 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 scheme: the use of biostimulant poly-rhamnosyl glutamate (APAA) in the preparation of urea products improves nitrogen utilization.

[0008] The second object of the present invention is implemented by the following technical scheme: a method for preparing composite biostimulant urea, which comprises the following steps: (1) catalytically synthesizing molten urea liquid from a basic urea raw material; (2) evaporating the molten urea liquid and adding the biostimulant APAA during the evaporation stage to obtain a composite granulation raw material; (3) granulating the composite granulation raw material to obtain the composite biostimulant urea.

[0009] Specifically, the step (2) includes: S1: one evaporation to obtain a concentrated urea solution; S2: adding biostimulant APAA to the primary urea concentrate to obtain a composite urea concentrate; S3: The composite urea liquid concentrate is concentrated twice to obtain a composite granulation raw material.

[0010] Specifically, the mass ratio of the biostimulant APAA to the composite biostimulant urea is 1:250 to 1:166.

[0011] The third object of the present invention is implemented by the following technical scheme: the composite biostimulant urea is prepared by the preparation method of the composite biostimulant urea described in the second object of the present invention.

[0012] Advantages of the present invention: (1) The present invention adds the biostimulant APAA to the nitrogen fertilizer, which has the effects of stabilizing, promoting growth and resisting stress such as low temperature and salinity, and passivating heavy metals.

[0013] (2) The urea prepared by the present invention contains various types of nitrogen, including fast-acting ammonium nitrogen and amide nitrogen, as well as a certain amount of organic nitrogen. Its composition conforms to the nitrogen demand of most crops, so the nitrogen utilization rate is significantly improved.

[0014] (3) The biostimulant APAA added in the present invention is a multi-element 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 growth, resisting stress, and rooting of crops, and retaining water and fertilizer in the soil, thereby achieving a comprehensive regulatory effect on fertilizers, crops, and soil. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 The present invention is a flow chart of the preparation method of the composite biostimulant urea; Figure 2 To treat corn growth conditions in different ways; Figure 3 This is a comparison of the growth of Auricularia auricula in the control group CK and the experimental group APAA before low temperature treatment; Figure 4 This is a comparison of the growth of the control group CK and the experimental group APAA Auricularia auricula after being placed in a 5°C environment for 72 hours; Figure 5 This is a comparison of the recovery of the leaves of the control group CK and the experimental group APAA after being placed in room temperature. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] Example 1: Figure 1 As shown, the preparation method of composite biostimulant urea comprises the following steps: (1) Catalytic synthesis of molten urea liquid from basic urea raw materials; the basic urea raw materials include liquid ammonia and carbon dioxide; the liquid ammonia is prepared by synthetic ammonia, the carbon dioxide is purified by a gas production system, and the basic urea raw materials are prepared according to existing technology or directly purchased; in this embodiment, the basic urea raw materials are prepared according to existing technology. In the production process of urea, the basic urea raw materials, liquid ammonia and carbon dioxide, are catalytically synthesized into molten urea liquid in a catalytic tower.

[0019] (2) The molten urea solution is evaporated and the biostimulant APAA is added during the evaporation stage to obtain a composite granulation raw material: the biostimulant APAA is purchased from Qingdao Haid Biotechnology Group Co., Ltd.

[0020] S1: one evaporation to obtain a concentrated urea solution; S2: adding biostimulant APAA to the primary urea concentrate to obtain a composite urea concentrate; in this embodiment, the biostimulant APAA liquid is added between the first and second evaporators (i.e., the first and second evaporators) at a flow rate of 338.54 kg / h (the flow rate is calculated based on a standard daily urea production system of 1,625 tons), and mixed and dissolved by relying on the system pressure; S3: The composite urea liquid concentrate is concentrated twice to obtain a composite granulation raw material.

[0021] (3) The composite granulation raw materials are granulated to obtain composite biostimulant urea.

[0022] The processes of primary evaporation, secondary evaporation, granulation, etc. belong to the existing technology and will not be introduced in detail here.

[0023] After testing, the prepared composite biostimulant urea has a nitrogen content of 46.38% and a moisture content of 0.25%, which meets the requirements of the standard GB2440-2017 urea qualified products. The nitrogen content and moisture content are determined in accordance with the relevant provisions of GB2440-2017 urea.

[0024] Comparative Example 1: The difference between the preparation method of Example 1 is that the biostimulant APAA is replaced by a biostimulant mixed with alginate and polyglutamic acid in a mass ratio of 1:1.2, and the other processing methods and parameters are exactly the same as those of Example 1.

[0025] Fertilizer efficiency test 1: Rooting and growth promotion test on corn The experimental treatments are shown in Table 1: Table 1 Experimental treatments

[0026] In the test treatment, 28-6-7 product was selected as the base fertilizer for corn. After corn was sown, thinning was carried out to ensure uniform growth. Normal watering and weeding were carried out during the period. When the corn grew to the 6-7 leaf stage (i.e., the large trumpet stage), fertilization was carried out according to the test treatment. T1 used 20 kg / mu of urea prepared in comparative example 1, and T2 used 20 kg / mu of urea prepared in example 1. The fertilizer amount of T2 was the same as that of T1; T3 used 17 kg / mu of urea prepared in example 1 (85% of the urea fertilizer amount prepared in comparative example 1, i.e., 15% weight loss). Observe the leaf color value, plant height, leaf width, etc. Figure 2 The detected leaf nitrogen content and leaf area are shown in Table 2.

[0027] Test conclusion: Different treatments, from the perspective of growth, the application of urea prepared in Example 1 is more obvious than the application of urea prepared in Comparative Example 1. The growth of corn is higher, the stalks 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. The effect of reducing the use amount of urea prepared in Example 1 by 15% (T3) is more significant in terms of leaf width than that prepared in Comparative Example 1 (T1). 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.

[0028] Table 2: Nitrogen content and leaf area of ​​corn leaves under different treatments

[0029] Test 2: Low temperature resistance test In the low temperature resistance test, Auricularia auricula was used to simulate a sudden low temperature environment, and the growth performance of Auricularia auricula under low temperature conditions was observed. The main focus was on observing the degree of foliar fertilizer damage and the recovery after returning to normal temperature conditions, so as to observe the low temperature resistance effect of APAA products.

[0030] Table 3 Experimental treatment (APAA urea is the urea prepared in Example 1, hereinafter referred to as APAA)

[0031] Results: To simulate a continuous low temperature environment, the Auricularia auricula was placed in a low temperature environment of 5°C for 72 hours. Figure 4 As shown in the figure, most leaves in the control group CK have wilted, indicating that they have been harmed by low temperature. A small number of leaves of the Auricularia auricula treated with APAA in the experimental group have slight damage on the edges, the damage is not obvious, and the leaves wilt slightly. The damage to the leaves after low temperature is irreversible.

[0032] Continue to keep it at room temperature and observe the recovery of the leaves.

[0033] Results: Figure 5 As shown, the leaves of the control group CK were damaged by frost and could not be recovered from the adversity, and there were still wilted leaves on the edges of the leaves; while the leaves of the experimental group APAA had basically recovered to a healthy state.

[0034] Conclusion: APAA can improve the low temperature resistance of crops. For sudden temperature drop or sustained low temperature, spraying or topdressing APAA products in advance can induce the expression of plant stress resistance genes, improve plant low temperature resistance, and reduce low temperature damage.

[0035] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. Application of biostimulant poly-rhamnosyl glutamate in the preparation of urea products.

2. A method for preparing composite biostimulant urea, characterized in that: The method comprises the following steps: (1) catalyzing a basic urea raw material to synthesize a molten urea solution; (2) evaporating the molten urea solution and adding a biostimulant polymerized rhamnosyl glutamate during the evaporation stage to obtain a composite granulation raw material; and (3) granulating the composite granulation raw material to prepare a composite biostimulant urea.

3. The method for preparing the composite biostimulant urea according to claim 2, characterized in that: 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 liquid concentrate is concentrated twice to obtain a composite granulation raw material.

4. The method for preparing the composite biostimulant urea according to claim 3, characterized in that: The mass ratio of the biostimulant polymerized rhamnosyl glutamate to the composite biostimulant urea is 1:250 to 1:

166.

5. The composite biostimulant urea prepared by the preparation method of the composite biostimulant urea according to any one of claims 2 to 4.

Images