Gelatin-based hydrogel macroelement suspension fertilizer and preparation method thereof

Abstract

The invention belongs to but not limited to the technical field of suspension fertilizer preparation, and particularly relates to a gelatin-based hydrogel macroelement suspension fertilizer preparation method, which comprises: 1, weighing raw materials according to a certain ratio; step 2, soaking gelatin in distilled water for 24 hours, putting a mixture of the gelatin and the distilled water into a stirrer, and heating and stirring in a water bath at 70 DEG C until the gelatin is completely dissolved; step 3, adding citric acid into the gelatin solution, continuously heating in a water bath at 70 DEG C for 2.5 hours, and cooling to room temperature to form gelatin-based hydrogel; 4, uniformly mixing the distilled water and the amino acid waste liquid through mechanical stirring; 5, increasing the rotating speed, adding gelatin-based hydrogel, and stirring until a large number of bubbles are generated; and step 6, grinding urea, monoammonium phosphate, potassium chloride, bentonite and potassium fulvate, increasing the rotating speed, sequentially feeding at the same time interval, and homogenizing for 30 minutes after the feeding is finished.

Description

Technical Field

[0001] The invention belongs to but is not limited to the technical field of suspended fertilizer preparation, and in particular relates to a method for preparing a gelatin-based hydrogel macroelement suspended fertilizer. Background Art

[0002] Liquid fertilizers are generally divided into suspended fertilizers and clear liquid fertilizers. The nutrient content of clear liquid fertilizers is as high as about 40%, while suspended liquid fertilizers are highly concentrated liquid fertilizers, which are composed of components that are completely dissolved in water and insoluble components distributed in the system in the form of dispersants. The total nutrient content can reach 45%, or even higher. Due to its high nutrient content and the advantages of flexible formula control, it has a very broad application prospect and is also a key raw material in the application of water-fertilizer integration technology. The development of composite suspended fertilizers to meet the requirements of crops for multiple nutrients is currently the focus of suspended fertilizer development.

[0003] However, when suspended fertilizers are placed for a long time, they will have significant problems such as stratification, paste, coagulation, serious bottoming, low suspension rate, and poor redispersibility. In particular, the stratification problem is prevalent with the commercialization process of suspended fertilizers, and it has long been an important factor restricting the development and application of suspended fertilizers. Due to stratification, the quality of the product is reduced, and a large number of supersaturated particles in the suspension system are very easy to stratify and precipitate, and finally connected at the bottom by crystal bridges, forming serious compaction. Therefore, the production and use of suspended fertilizer products need to be completed in a relatively short period of time to achieve a better fertilization effect, and the requirements for production cycle and storage conditions are relatively strict.

[0004] At present, in order to ensure the uniformity and stability of suspended particles, multiple additives such as suspending agents, dispersants, defoamers, antifreeze agents, thickeners, chelating agents, etc. are often used to improve the stability of suspended fertilizers. Commonly used suspending agents include: magnesium aluminum silicate, sodium carboxymethyl cellulose and other materials, but the compounding of multiple additives will make the composition of suspended fertilizers more complicated, increase production costs and increase the interaction between the components in the system. Some additives cannot be used or degraded by the soil, and even bring irreversible harm to the land environment. At the same time, the large-scale use of such water-insoluble raw materials is prone to pipeline blockage during long-term use.

[0005] In view of this, the present invention is proposed. Summary of the invention

[0006] The purpose of the present invention is to provide a gelatin-based hydrogel macronutrient suspension fertilizer and a preparation method thereof, which can improve the stability of the suspension fertilizer, delay stratification and precipitation, and at the same time, can utilize harmless animal processing by-product gelatin to achieve the purpose of improving nutrients, thereby solving the deficiencies in the above-mentioned technologies.

[0007] The present invention provides the following technical solution: a gelatin-based hydrogel macro-element suspension fertilizer, comprising the following materials: 230 g urea, 135 g monoammonium phosphate, 215 g potassium chloride, 150 g amino acid fermentation liquid, 150 g water, 100 g gelatin-based hydrogel, and 20 g bentonite.

[0008] The present invention provides the following technical solution: a method for preparing a gelatin-based hydrogel macronutrient suspension fertilizer, comprising the following steps:

[0009] Step 1, weigh the raw materials according to proportion;

[0010] Step 2: After the gelatin is soaked in distilled water for 24 hours, the mixture of gelatin and distilled water is placed in a blender, heated in a 70° C. water bath and stirred until the gelatin is completely dissolved;

[0011] Step 3, adding citric acid to the gelatin solution, continuing to heat in a 70° C. water bath for 2.5 h and then cooling to room temperature to form a gelatin-based hydrogel;

[0012] Step 4, mixing the distilled water and the amino acid waste liquid uniformly by mechanical stirring;

[0013] Step 5, after increasing the speed, add the gelatin-based hydrogel and stir until a large number of bubbles are generated;

[0014] Step six, grinding urea, monoammonium phosphate, potassium chloride, bentonite and potassium humate, increasing the rotation speed and feeding them in sequence at the same interval, and homogenizing for 30 minutes after the feeding is completed.

[0015] Further, citric acid-gelatin based hydrogel is an additive.

[0016] Furthermore, in step 2, the raw materials of the gelatin-based hydrogel are 30 parts of gelatin and 100 parts of water, and the stirrer speed is 400-500r / min.

[0017] Further, in step 3, 6 parts of citric acid are added and the stirring speed is 400-500r / min.

[0018] Furthermore, in step 4, the amount of amino acid waste liquid added is 125 parts, the mechanical stirring speed is 300-400r / min, and the stirring time is 10min.

[0019] Furthermore, in step five, the gelatin-based hydrogel and water are added in an amount of 250 parts in total, and the mechanical stirring speed is 600-700 r / min.

[0020] Furthermore, in step six, the addition amount of each component of the gelatin-based hydrogel suspension fertilizer is 230 parts of urea, 135 parts of monoammonium phosphate, 215 parts of potassium chloride, 20 parts of bentonite, and 10 parts of potassium humate. The grinding is 60-200 mesh, the mechanical stirring speed is 900-1100r / min, and the feeding interval time is 10min.

[0021] The present invention also provides a method for preparing a gelatin-based hydrogel macronutrient suspension fertilizer, comprising the following steps:

[0022] (1) Soak gelatin in distilled water at a ratio of 1:5 for 2-3 hours, and then heat to 50-60°C to dissolve the gelatin;

[0023] (2) adding citric acid to the gelatin solution at a ratio of 1-3% and stirring evenly to form a gelatin-based hydrogel;

[0024] (3) The prepared gelatin-based hydrogel is gradually mixed and stirred with the following components according to weight percentage: 10-15% of amino acid waste liquid, 5-10% of urea, 10-15% of monoammonium phosphate, 5-8% of potassium chloride, 2-5% of bentonite, and 2-4% of potassium humate, and the mixture is gradually mixed and stirred at different rotation speeds to finally prepare a gelatin-based hydrogel macroelement suspended fertilizer with suspension properties and fertilizer effect.

[0025] Furthermore, the amino acid waste liquid, urea, monoammonium phosphate, potassium chloride, bentonite and potassium humate are mixed in the following order:

[0026] (1) firstly mixing the amino acid waste liquid with the gelatin-based hydrogel;

[0027] (2) then adding urea, monoammonium phosphate, and potassium chloride in sequence, and stirring at a speed of 500-800 rpm for 10-15 minutes;

[0028] (3) Finally, add bentonite and potassium humate, and stir at 300-500 rpm until uniformly suspended.

[0029] In combination with the above technical solutions and the technical problems solved, the advantages and positive effects of the technical solutions to be protected by the present invention are as follows:

[0030] First, the gelatin-based suspended fertilizer provided by the present invention has good stability. When the gelatin-based hydrogel suspension fertilizer with a gelatin-based hydrogel addition amount of 10% can be stably stored for 35 days at room temperature without stratification, the suspended fertilizer without gelatin addition begins to stratify after 28 days of storage at room temperature, and the storage time of the gelatin-based hydrogel suspension fertilizer is increased by 25%. The solid-liquid ratio of the lower layer of the gelatin-based hydrogel with a hydrogel addition amount of 10% changes to 0.65-1.02 within 10 days of storage, which increases by 85%, and the solid-liquid ratio of the lower layer of the suspended fertilizer without hydrogel addition changes to 0.57-1.11, which increases by 95%. The solid-liquid ratio of the lower layer of the gelatin-based hydrogel suspension fertilizer increases slowly, showing good stability.

[0031] Second, the gelatin-based suspended fertilizer prepared by the present invention has a high amino acid content. The hydrolyzed amino acid content of the gelatin-based hydrogel suspended fertilizer with a hydrogel addition amount of 10% is 26.808 mg / mL, and the hydrolyzed amino acid content of the gelatin-based hydrogel suspended fertilizer without the addition of the gelatin-based hydrogel is 9.378 mg / mL, and the amino acid content of the gelatin-based hydrogel suspended fertilizer is increased by 187%. The gelatin-based hydrogel used in the present invention can provide organic matter content and further improve fertilizer efficiency.

[0032] Third, as auxiliary evidence of the inventiveness of the claims of the present invention, it is also reflected in the following important aspects:

[0033] (1) The suspended fertilizer of the present invention has good dispersibility in water. When applying fertilizer, the nutrient particles in the fertilizer can be evenly applied and covered on the soil surface, which can effectively avoid uneven fertilization caused by uneven fertilizer composition, affecting crop growth, and even causing soil compaction due to excessive fertilization.

[0034] (2) The gelatin-based suspended fertilizer provided by the present invention can fully utilize gelatin, a by-product of animal processing, as an auxiliary material, which can not only realize the recycling of resources, but also avoid the pollution of the environment by animal processing waste, thereby achieving the effect of saving and protecting the environment, and helping to promote the production and application of environmentally friendly composite suspended fertilizers.

[0035] (3) The gelatin-based hydrogel prepared by the present invention using an appropriate process is added to the suspended fertilizer system, which effectively improves the suspension stability while also increasing the content of hydrolyzable amino acids in the suspended fertilizer, thereby effectively improving the nutrients of the suspended fertilizer. After being applied to the soil, the gelatin-based hydrogel can be degraded into small molecule amino acids, which are harmless to the soil and easily absorbed by crops, thereby promoting crop growth.

[0036] (4) The gelatin-based hydrogel used as the main suspending agent in the present invention is a slightly physically cross-linked hydrogel, which replaces part of the traditional insoluble and degradable excipients, and can effectively reduce the degree of blockage of the pipeline during fertilization and the impact of changes in soil properties caused by the large-scale use of traditional excipients.

[0037] Fourthly, the present invention solves the technical problems of poor suspension stability, uneven mixing, and unsustainable fertilizer effect in the preparation process of hydrogel suspension fertilizer in the prior art by precisely controlling the parameters in each step, and has achieved significant technical progress.

[0038] 1. Parameter control of gelatin dissolution and hydrogel formation: The present invention stirs gelatin in a 70°C water bath to ensure that it is completely dissolved, and continues to heat for 2.5 hours after adding citric acid to form a stable gelatin-based hydrogel. This step solves the problems of incomplete dissolution and unstable gel structure in traditional hydrogel preparation by controlling temperature and time, and improves the finished product quality and stability of the hydrogel.

[0039] 2. Control of mixing parameters of amino acid waste liquid and gelatin-based hydrogel: When stirring the amino acid waste liquid, the present invention strictly controls the stirring speed (300-400r / min) and time (10min), and adds the gelatin-based hydrogel after increasing the stirring speed to 600-700r / min to ensure that the mixture generates a large number of bubbles, thereby enhancing the suspension of the fertilizer. By optimizing the stirring parameters, the problem of uneven mixing in the prior art is solved, ensuring the uniformity and stability of the product.

[0040] 3. Feeding and grinding parameter control of macroelements: When adding macroelements such as urea, monoammonium phosphate, potassium chloride, bentonite, potassium humate, etc. to the suspension fertilizer, the present invention gradually increases the stirring speed to 900-1100r / min, controls the addition interval of each component (10 minutes), and controls the grinding fineness to 60-200 meshes to ensure that each component is fully mixed and evenly dispersed. This process solves the problem of uneven fertilizer effect caused by uneven particles in the prior art, and improves the stability and use effect of the suspension fertilizer.

[0041] Through the precise control of the above parameters, the present invention successfully prepares a gelatin-based hydrogel macronutrient suspension fertilizer with excellent suspension, mixing uniformity and lasting fertilizer effect. The suspension fertilizer not only achieves a significant improvement in suspension stability, but also can effectively release nutrients and extend the shelf life of the fertilizer, thereby improving the efficiency and quality of agricultural production. At the same time, the preparation method of the present invention is easy to industrialize and has broad market prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 This is a flow chart of a method for preparing a gelatin-based hydrogel macronutrient suspension fertilizer provided by an embodiment of the present invention;

[0043] Figure 2 It is a graph showing the change of solid-liquid ratio, pH value and viscosity of Example 2 and Control Group 1 provided in the Examples of the present invention after standing at 25° C. for 5 weeks;

[0044] Figure 3 It is a visual diagram of Example 2 and Control Group 1 provided in the Examples of the present invention left to stand at 25° C. for 5 weeks;

[0045] Figure 4 It is a flow chart of the preparation of gelatin-based hydrogel suspension fertilizer provided by an embodiment of the present invention;

[0046] Figure 5 is the XRD pattern of the gelatin-based hydrogel provided in an embodiment of the present invention;

[0047] Figure 6 is an infrared spectrum of the gelatin-based hydrogel provided by an embodiment of the present invention;

[0048] Figure 7 It is a diagram of the formation mechanism of the gelatin-based hydrogel provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0049] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0050] like Figure 1 As shown, the method for preparing a gelatin-based hydrogel macronutrient suspension fertilizer provided by an embodiment of the present invention comprises:

[0051] S101, weighing raw materials according to proportion;

[0052] S102, after soaking the gelatin in distilled water for 24 hours, placing the mixture of gelatin and distilled water in a stirrer, heating in a 70° C. water bath and stirring until the gelatin is completely dissolved;

[0053] S103, adding citric acid to the gelatin solution, continuing to heat in a 70° C. water bath for 2.5 h, and then cooling to room temperature to form a gelatin-based hydrogel;

[0054] S104, mixing the distilled water and the amino acid waste liquid uniformly by mechanical stirring;

[0055] S105, after increasing the rotation speed, adding gelatin-based hydrogel and stirring until a large number of bubbles are generated;

[0056] S106, grinding urea, monoammonium phosphate, potassium chloride, bentonite, and potassium humate, increasing the rotation speed, and feeding them in sequence at the same interval, and homogenizing for 30 minutes after the feeding is completed.

[0057] Citric acid-gelatin based hydrogel is an additive.

[0058] The raw materials of the gelatin-based hydrogel in S101 are 30 parts of gelatin, 100 parts of water, and 6 parts of citric acid.

[0059] The agitator speed in S102 is 400-500r / min.

[0060] S103 contains 6 parts of citric acid and the stirring speed is 400-500r / min.

[0061] The amount of amino acid waste liquid added to S104 is 125 parts, the mechanical stirring speed is 300-400r / min, and the stirring time is 10min.

[0062] The amount of gelatin-based hydrogel and water added to S105 was 250 parts in total, and the mechanical stirring speed was 600-700 r / min.

[0063] The addition amounts of the components of the gelatin-based hydrogel suspension fertilizer in S106 are 230 parts of urea, 135 parts of monoammonium phosphate, 215 parts of potassium chloride, 20 parts of bentonite, and 10 parts of potassium humate. The mixture is ground into 60-200 mesh, the mechanical stirring speed is 900-1100 r / min, and the feeding interval is 10 min.

[0064] Embodiment 1:

[0065] Furthermore, the preparation method of the gelatin-based hydrogel suspension fertilizer comprises:

[0066] Step 1, weigh the raw materials according to proportion;

[0067] Step 2: After soaking gelatin (30 parts) in distilled water (100 parts) for 24 hours, the mixture of gelatin and distilled water is placed in a stirrer, heated in a 70° C. water bath and stirred until the gelatin is completely dissolved;

[0068] Step 3, adding citric acid (6 parts) to the gelatin solution, continuing to heat in a 70°C water bath for 2.5 hours and then cooling to room temperature to form a gelatin-based hydrogel;

[0069] Step 4: mechanically stirring a mixture of distilled water (200 parts) and amino acid waste liquid (125 parts) at 300 r / min for 10 min;

[0070] Step 5, then add gelatin-based hydrogel (50 parts) and adjust the speed to 700 r / min and stir until a large number of bubbles are generated;

[0071] Step six, grind urea (230 parts), monoammonium phosphate (135 parts), potassium chloride (215 parts), bentonite (20 parts), and potassium humate (10 parts), pass through a 60-mesh sieve, and add them in sequence every 10 minutes. After the feeding is completed, homogenize for 30 minutes.

[0072] Embodiment 2:

[0073] Furthermore, the preparation method of the gelatin-based hydrogel suspension fertilizer comprises:

[0074] Step 1, weigh the raw materials according to proportion;

[0075] Step 2: After soaking gelatin (30 parts) in distilled water (100 parts) for 24 hours, the mixture of gelatin and distilled water is placed in a stirrer, heated in a 70° C. water bath and stirred until the gelatin is completely dissolved;

[0076] Step 3, adding citric acid (6 parts) to the gelatin solution, continuing to heat in a 70°C water bath for 2.5 hours and then cooling to room temperature to form a gelatin-based hydrogel;

[0077] Step 4: mechanically stirring a mixture of distilled water (150 parts) and amino acid waste liquid (125 parts) at 300 r / min for 10 min;

[0078] Step 5, then add gelatin-based hydrogel (100 parts) and adjust the speed to 700 r / min and stir until a large number of bubbles are generated;

[0079] Step six, grind urea (230 parts), monoammonium phosphate (135 parts), potassium chloride (215 parts), bentonite (20 parts), and potassium humate (10 parts), pass through a 60-mesh sieve, and add them in sequence every 10 minutes. After the feeding is completed, homogenize for 30 minutes.

[0080] Embodiment 3:

[0081] Furthermore, the preparation method of the gelatin-based hydrogel suspension fertilizer comprises:

[0082] Step 1, weigh the raw materials according to proportion;

[0083] Step 2: After soaking gelatin (30 parts) in distilled water (100 parts) for 24 hours, the mixture of gelatin and distilled water is placed in a stirrer, heated in a 70° C. water bath and stirred until the gelatin is completely dissolved;

[0084] Step 3, adding citric acid (6 parts) to the gelatin solution, continuing to heat in a 70°C water bath for 2.5 hours and then cooling to room temperature to form a gelatin-based hydrogel;

[0085] Step 4, mechanically stirring a mixture of distilled water (100 parts) and amino acid waste liquid (125 parts) at 300 r / min for 10 min;

[0086] Step 5, then add gelatin-based hydrogel (150 parts) and adjust the speed to 700 r / min and stir until a large number of bubbles are generated;

[0087] Step six, grind urea (230 parts), monoammonium phosphate (135 parts), potassium chloride (215 parts), bentonite (20 parts), and potassium humate (10 parts), pass through a 60-mesh sieve, and add them in sequence every 10 minutes. After the feeding is completed, homogenize for 30 minutes.

[0088] Embodiment 4:

[0089] Furthermore, the preparation method of the gelatin-based hydrogel suspension fertilizer comprises:

[0090] Step 1, weigh the raw materials according to proportion;

[0091] Step 2: After soaking gelatin (30 parts) in distilled water (100 parts) for 24 hours, the mixture of gelatin and distilled water is placed in a stirrer, heated in a 70° C. water bath and stirred until the gelatin is completely dissolved;

[0092] Step 3, adding citric acid (6 parts) to the gelatin solution, continuing to heat in a 70°C water bath for 2.5 hours and then cooling to room temperature to form a gelatin-based hydrogel;

[0093] Step 4: mechanically stirring a mixture of distilled water (150 parts) and amino acid waste liquid (125 parts) at 300 r / min for 10 min;

[0094] Step 5, then add gelatin-based hydrogel (100 parts) and adjust the speed to 700 r / min and stir until a large number of bubbles are generated;

[0095] Step six: urea (230 parts), monoammonium phosphate (135 parts), potassium chloride (215 parts), bentonite (20 parts), and potassium humate (10 parts) are not ground, and are added in sequence at intervals of 10 minutes. After the addition is completed, homogenize for 30 minutes.

[0096] Embodiment 5:

[0097] Furthermore, the preparation method of the gelatin-based hydrogel suspension fertilizer comprises:

[0098] Step 1, weigh the raw materials according to proportion;

[0099] Step 2: After soaking gelatin (30 parts) in distilled water (100 parts) for 24 hours, the mixture of gelatin and distilled water is placed in a stirrer, heated in a 70° C. water bath and stirred until the gelatin is completely dissolved;

[0100] Step 3, adding citric acid (6 parts) to the gelatin solution, continuing to heat in a 70°C water bath for 2.5 hours and then cooling to room temperature to form a gelatin-based hydrogel;

[0101] Step 4: mechanically stirring a mixture of distilled water (150 parts) and amino acid waste liquid (125 parts) at 300 r / min for 10 min;

[0102] Step 5, then add gelatin-based hydrogel (100 parts) and adjust the speed to 700 r / min and stir until a large number of bubbles are generated;

[0103] Step six, grind urea (230 parts), monoammonium phosphate (135 parts), potassium chloride (215 parts), bentonite (20 parts), and potassium humate (10 parts), pass through a 100-mesh sieve, and add them in sequence every 10 minutes. After the feeding is completed, homogenize for 30 minutes.

[0104] Embodiment 6:

[0105] Furthermore, the preparation method of the gelatin-based hydrogel suspension fertilizer comprises:

[0106] Step 1, weigh the raw materials according to proportion;

[0107] Step 2: After soaking gelatin (30 parts) in distilled water (100 parts) for 24 hours, the mixture of gelatin and distilled water is placed in a stirrer, heated in a 70° C. water bath and stirred until the gelatin is completely dissolved;

[0108] Step 3, adding citric acid (6 parts) to the gelatin solution, continuing to heat in a 70°C water bath for 2.5 hours and then cooling to room temperature to form a gelatin-based hydrogel;

[0109] Step 4: mechanically stirring a mixture of distilled water (150 parts) and amino acid waste liquid (125 parts) at 300 r / min for 10 min;

[0110] Step 5, then add gelatin-based hydrogel (100 parts) and adjust the speed to 700 r / min and stir until a large number of bubbles are generated;

[0111] Step six, grind urea (230 parts), monoammonium phosphate (135 parts), potassium chloride (215 parts), bentonite (20 parts), and potassium humate (10 parts), pass through a 160-mesh sieve, and add them in sequence every 10 minutes. After the feeding is completed, homogenize for 30 minutes.

[0112] Embodiment 7:

[0113] Furthermore, the preparation method of the gelatin-based hydrogel suspension fertilizer comprises:

[0114] Step 1, weigh the raw materials according to proportion;

[0115] Step 2: After soaking gelatin (30 parts) in distilled water (100 parts) for 24 hours, the mixture of gelatin and distilled water is placed in a stirrer, heated in a 70° C. water bath and stirred until the gelatin is completely dissolved;

[0116] Step 3, adding citric acid (6 parts) to the gelatin solution, continuing to heat in a 70°C water bath for 2.5 hours and then cooling to room temperature to form a gelatin-based hydrogel;

[0117] Step 4: mechanically stirring a mixture of distilled water (150 parts) and amino acid waste liquid (125 parts) at 300 r / min for 10 min;

[0118] Step 5, then add gelatin-based hydrogel (100 parts) and adjust the speed to 700 r / min and stir until a large number of bubbles are generated;

[0119] Step six, grind urea (230 parts), monoammonium phosphate (135 parts), potassium chloride (215 parts), bentonite (20 parts), and potassium humate (10 parts), pass through a 200-mesh sieve, and add them in sequence every 10 minutes. After the feeding is completed, homogenize for 30 minutes.

[0120] Comparative Example 1:

[0121] Furthermore, the preparation method of the gelatin-based hydrogel suspension fertilizer comprises:

[0122] Step 1, weigh the raw materials according to proportion;

[0123] Step 2: A mixture of distilled water (250 parts) and amino acid waste liquid (125 parts) was mechanically stirred at 300 r / min for 10 min;

[0124] Step three, grind urea (230 parts), monoammonium phosphate (135 parts), potassium chloride (215 parts), bentonite (20 parts), and potassium humate (10 parts), pass through a 60-mesh sieve, and add them in sequence every 10 minutes. After the feeding is completed, homogenize for 30 minutes.

[0125] Comparative Example 2:

[0126] Furthermore, the preparation method of the gelatin-based hydrogel suspension fertilizer comprises:

[0127] Step 1, weigh the raw materials according to proportion;

[0128] Step 2: After soaking gelatin (30 parts) in distilled water (100 parts) for 24 hours, the mixture of gelatin and distilled water is placed in a stirrer, heated in a 70° C. water bath and stirred until the gelatin is completely dissolved;

[0129] Step 3, adding citric acid (6 parts) to the gelatin solution, continuing to heat in a 70°C water bath for 2.5 hours and then cooling to room temperature to form a gelatin-based hydrogel;

[0130] Step 4: mechanically stirring a mixture of distilled water (150 parts) and amino acid waste liquid (125 parts) at 300 r / min for 10 min;

[0131] Step 5, then add gelatin-based hydrogel (100 parts) and adjust the speed to 700 r / min and stir until a large number of bubbles are generated;

[0132] Step six, urea (230 parts), monoammonium phosphate (135 parts), potassium chloride (215 parts), bentonite (20 parts), and potassium humate (10 parts) are added in sequence at intervals of 10 minutes without grinding, and homogenized for 30 minutes after the addition is completed.

[0133] Effect verification 1: The samples prepared in the embodiment and the control group were stored at room temperature for 10 days to evaluate their stability, where the stability evaluation indexes were mainly based on the pH value and solid-liquid ratio of the suspension system, as shown in Table 1. The treatment conditions of the suspension system are as follows: 0%, 5%, 10%, and 15% of gelatin-based hydrogel were added respectively, and the effect of its content change on the stability of the system was observed; the gelatin-based hydrogel content was kept at 10%, and the stability of the solid raw materials when they were: not ground, ground through a 60-mesh screen, ground through a 100-mesh screen, ground through a 150-mesh screen, and ground through a 200-mesh screen. The change in the solid-liquid ratio of the lower layer is caused by the sedimentation of solid particles in the system, which is an important factor in measuring the stability of suspended fertilizers. The stability analysis data is shown in Table 1. In the same time period, the system is relatively stable when the solid-liquid ratio is smaller. Among them, the change in pH value data can reflect the degree of chemical changes in the system.

[0134] Table 1 Physical stability analysis of gelatin-based hydrogel suspension fertilizer

[0135]

[0136] Test results: It can be seen from Table 1 that the amount of gelatin-based hydrogel added and the particle size of the inorganic salt component in the gelatin-based hydrogel suspension fertilizer have a significant effect on the stability of the gelatin-based hydrogel suspension fertilizer; compared with other formulas, the amount of gelatin-based hydrogel added in Example 2 is 10%, and when the inorganic salt component is crushed to pass through a 60-mesh sieve, it can significantly reduce the increase in the solid-liquid ratio of the gelatin-based hydrogel suspension fertilizer and improve the stability of the suspension fertilizer.

[0137] Effect verification 2: The suspended fertilizers of Example 2 and Control Group 1 were stored in a 25°C environment, and the solid-liquid ratio of the lower layer was measured every week. Figure 2 -a, Figure 2 -d)、pH( Figure 2 -b, Figure 2 -e) and viscosity ( Figure 2 -c, Figure 2 -f) to carry out the determination.

[0138] Test results: The solid mass of the lower layer of the suspended fertilizer in Example 2 increased slowly during the storage of 0-4 weeks, indicating that the gelatin-based hydrogel can maintain a relatively stable state in the first four weeks of storage. After the third week of storage, the solid-liquid ratio of the suspended fertilizer group in the control group 1 increased significantly, that is, from the third week onwards, the particle sedimentation rate of the suspended fertilizer group became faster and could not maintain a stable state. This shows that the three-dimensional network structure of the gelatin-based hydrogel in Example 2 effectively prevented the sedimentation of inorganic salt particles, and the suspended fertilizer system remained in a relatively stable state.

[0139] During storage, the pH of both Example 2 and Control Group 1 increased slowly and finally stabilized at about 4.3, so the pH change of the system was due to the slow fermentation of the amino acid waste liquid. The viscosity of Example 2 increased from 2314 to 3060, while that of Control Group 1 increased from 2479 to 2665, so the gelatin polypeptide chain in the gelatin-based hydrogel still had the phenomenon of gel-sol conversion during the storage of the gelatin-based hydrogel suspended fertilizer, thereby enhancing the physical stability of the suspended fertilizer.

[0140] The suspended fertilizers of Example 2 and Control Group 1 were stored in a 25°C environment and recorded every week. Figure 3 shown. Figure 3 -(a) is a suspension fertilizer without hydrogel. The suspension fertilizer began to stratify after 4 weeks of storage, while the gelatin-based hydrogel suspension fertilizer ( Figure 3 -(b)) remained stable after 5 weeks of storage.

[0141] like Figure 3 As shown, group 1 ( Figure 3 -(a)) began to separate after 4 weeks of storage, while Example 2( Figure 3 -(b)) remained stable after 5 weeks of storage.

[0142] Effect verification 3: The amino acid content in Example 2 and Control Group 1 was compared. In Example 2 and Control Group 1, except for the addition of 10% gelatin-based hydrogel in Example 2, the contents of other components were the same. After testing, the following data were obtained, see Table 2:

[0143] Table 2 Amino acid content (mg / mL)

[0144]

[0145]

[0146] The test results show that the total content of hydrolyzed amino acids in control group 1 is 9.378 mg / mL, and the total amount of free amino acids in Example 2 is 8.372 mg / mL. The content values ​​are similar, indicating that the free amino acids in Example 2 and control group 1 are provided by amino acid tail liquid. However, the total amount of hydrolyzed amino acids in Example 2 increased to 26.808 mg / mL, which is 2.86 times higher than that in group 1, indicating that the increased amino acids are provided by the addition of gelatin-based hydrogel. The above results prove that the addition of gelatin-based hydrogel can greatly increase the amino acid content in suspended fertilizer and increase the nutritional density of suspended fertilizer.

[0147] In summary, the present invention prepares a physically cross-linked gelatin-based hydrogel suspended fertilizer. The gelatin-based hydrogel is used as an additive to make the suspended fertilizer system have a three-dimensional network structure, which significantly improves the stability of the suspended fertilizer and provides more organic nutrients.

[0148] Figure 4 The invention discloses a preparation process of a gelatin-based hydrogel suspension fertilizer.

[0149] In order to prove that the present invention prepares a gelatin-based hydrogel suspension fertilizer that forms a three-dimensional network hydrogel structure in a suspension system, the gelatin-based hydrogel is tested as follows, and the mechanism is explained, such as Figure 5 , Figure 6 , Figure 7 As shown. XRD spectrum ( Figure 5 ) shows that the peak at 2θ=7° in gelatin solution without citric acid represents the triple helix structure of gelatin. After adding citric acid, the peak disappears, which means that the triple helix structure is destroyed. Infrared spectrum ( Figure 6 ) at 3400cm -1 The peak at 1637cm is the amide A band of the gelatin molecule. After adding citric acid, the peak at this position shifts to the blue, indicating that the number of hydrogen bonds decreases. -1 The peak at 2900cm is the carbonyl peak. With the addition of citric acid, the peak at this position has red-shifted, which proves that the carbonyl groups on the gelatin molecular chain have re-formed hydrogen bonds. -1 -2940cm -1 A new absorption peak appeared, which indicated that the addition of CA protonated the amino group to form -NH 3 + , electrostatic interaction occurs between the protonated amino group and the hydroxyl group in the carboxyl group, forming a physical cross-linking bond point.

[0150] The above results prove that the triple helix structure of gelatin is dissociated into disordered and stretched single molecular chains under the action of citric acid. The amino groups on the molecular chains are protonated in an acidic environment and combine with the carboxyl groups of citric acid in an electrostatic way as the bonding points of the gel. At the same time, the hydrogen bonds formed between the carboxyl groups on the gelatin also serve as the bonding points of physical cross-linking. Figure 7 shown.

[0151] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any modifications, equivalent substitutions and improvements made by any technician familiar with the technical field within the technical scope disclosed by the present invention and within the spirit and principle of the present invention should be covered by the protection scope of the present invention.

Claims

1. A method for preparing a gelatin-based hydrogel macronutrient suspension fertilizer, characterized in that: The gelatin is soaked in distilled water, heated and dissolved, and citric acid is added to form a gelatin-based hydrogel. The hydrogel is then gradually mixed and stirred with amino acid waste liquid, urea, monoammonium phosphate, potassium chloride, bentonite, potassium humate and other macroelements in a specific proportion and sequence at different speeds to finally prepare a gelatin-based hydrogel macroelement suspended fertilizer with suspension and fertilizer effect.

2. The method for preparing the gelatin-based hydrogel macronutrient suspension fertilizer according to claim 1, characterized in that: The following steps are involved: (1) Soak gelatin in distilled water at a ratio of 1:5 for 2-3 hours, and then heat to 50-60°C to dissolve the gelatin; (2) adding citric acid to the gelatin solution at a ratio of 1-3% and stirring evenly to form a gelatin-based hydrogel; (3) The prepared gelatin-based hydrogel is gradually mixed and stirred with the following components according to weight percentage: 10-15% of amino acid waste liquid, 5-10% of urea, 10-15% of monoammonium phosphate, 5-8% of potassium chloride, 2-5% of bentonite, and 2-4% of potassium humate, and the mixture is gradually mixed and stirred at different rotation speeds to finally prepare a gelatin-based hydrogel macroelement suspended fertilizer with suspension properties and fertilizer effect.

3. The method for preparing the gelatin-based hydrogel macronutrient suspension fertilizer according to claim 2, characterized in that: The mixing order of the amino acid waste liquid, urea, monoammonium phosphate, potassium chloride, bentonite and potassium humate is: (1) firstly mixing the amino acid waste liquid with the gelatin-based hydrogel; (2) then adding urea, monoammonium phosphate, and potassium chloride in sequence, and stirring at a speed of 500-800 rpm for 10-15 minutes; (3) Finally, add bentonite and potassium humate, and stir at 300-500 rpm until uniformly suspended.

4. The method for preparing the gelatin-based hydrogel macronutrient suspension fertilizer according to claim 3, characterized in that: include: Step 1, weigh the raw materials according to proportion; Step 2: After the gelatin is soaked in distilled water for 24 hours, the mixture of gelatin and distilled water is placed in a blender, heated in a 70° C. water bath and stirred until the gelatin is completely dissolved; Step 3, adding citric acid to the gelatin solution, continuing to heat in a 70° C. water bath for 2.5 h and then cooling to room temperature to form a gelatin-based hydrogel; Step 4, mixing the distilled water and the amino acid waste liquid uniformly by mechanical stirring; Step 5, after increasing the speed, add the gelatin-based hydrogel and stir until a large number of bubbles are generated; Step six, grinding urea, monoammonium phosphate, potassium chloride, bentonite and potassium humate, increasing the rotation speed and feeding them in sequence at the same interval, and homogenizing for 30 minutes after the feeding is completed.

5. The method for preparing the gelatin-based hydrogel macronutrient suspension fertilizer according to claim 4, characterized in that: The gelatin-based hydrogel additive is a citric acid-gelatin-based hydrogel.

6. The method for preparing the gelatin-based hydrogel macronutrient suspension fertilizer according to claim 4, characterized in that: The raw materials of the gelatin-based hydrogel in step 1 are 30 parts of gelatin, 100 parts of water, and 6 parts of citric acid.

7. The method for preparing a gelatin-based hydrogel macronutrient suspension fertilizer according to claim 4, characterized in that: In step 2, the speed of the agitator is 400-500 r / min.

8. The method for preparing the gelatin-based hydrogel macronutrient suspension fertilizer according to claim 4, characterized in that: In step 4, the amount of amino acid waste liquid added is 125 parts, the mechanical stirring speed is 300-400r / min, and the stirring time is 10min.

9. The method for preparing a gelatin-based hydrogel macronutrient suspension fertilizer according to claim 4, characterized in that: In step 5, the gelatin-based hydrogel and water are added in a total of 250 parts, and the mechanical stirring speed is 600-700 r / min.

10. The method for preparing the gelatin-based hydrogel macronutrient suspension fertilizer according to claim 4, characterized in that: In step six, the addition amount of each component of the gelatin-based hydrogel suspension fertilizer is 230 parts of urea, 135 parts of monoammonium phosphate, 215 parts of potassium chloride, 20 parts of bentonite, and 10 parts of potassium humate. The mixture is ground into 60-200 mesh, the mechanical stirring speed is 900-1100r / min, and the feeding interval is 10min.

Images