A small granule dry suspension containing lignite and nutrient elements and a method for its preparation

Abstract

This invention relates to the field of agricultural application technology, and proposes a small-particle dry suspension containing lignite and nutrients, and its preparation method. The small-particle dry suspension containing lignite and nutrients includes a core layer and a quick-release layer. The core layer comprises the following components: lignite, disintegrant, dispersant, wetting agent, and a first binder. The quick-release layer comprises the following components: nitrogen source, phosphorus source, potassium source, wetting agent, and a second binder. The first binder comprises hydroxymethyl bisphenol A epoxy resin and / or epoxy resorcinol formaldehyde resin; the second binder is a polyethylene glycol solution of sodium silicate. This technical solution solves the problems of low lignite utilization and poor effectiveness of humic acid and coal gangue in existing technologies.

Description

Technical Field

[0001] This invention relates to the field of agricultural application technology, specifically to a small-particle dry suspension containing lignite and nutrients, and its preparation method. Background Technology

[0002] Lignite is a low-grade coal with the lowest degree of coalification. It is rich in free humic acid, which can promote crop growth. In addition, lignite contains coal gangue, a solid waste material that can not only improve soil but also provide organic matter needed by crops. However, the coal gangue and free humic acid in lignite are insoluble in water when used as fertilizer, thus limiting their effectiveness. Therefore, improving the utilization rate of lignite, reducing the environmental harm of coal gangue, and fully utilizing the benefits of humic acid and coal gangue in lignite are technical challenges that urgently need to be addressed by those skilled in the art. Summary of the Invention

[0003] This invention proposes a small-particle dry suspension containing lignite and nutrients, and its preparation method, which solves the problems of low lignite utilization and poor effect of humic acid and coal gangue in related technologies.

[0004] The technical solution of the present invention is as follows:

[0005] A small-particle dry suspension containing lignite and nutrients, comprising a core layer and an immediate-release layer;

[0006] The core layer comprises the following components: lignite, disintegrant, dispersant, wetting agent, and first binder;

[0007] The immediate-release layer comprises the following components: nitrogen source, phosphorus source, potassium source, wetting agent, and second binder;

[0008] The first adhesive comprises hydroxymethyl bisphenol A epoxy resin and / or epoxy resorcinol formaldehyde resin;

[0009] The second adhesive is a polyethylene glycol solution of sodium silicate.

[0010] When the small-particle dry suspension of the present invention is placed in water and stirred, the large number of elements in the immediate-release layer dissolve, the wetting agent comes into contact with water and is compatible, the disintegrant also plays a rapid role, the core layer disintegrates, and the coal gangue and free humic acid are uniformly dispersed in water under the action of the dispersant without precipitation.

[0011] As a further technical solution, the polyethylene glycol solution includes polyethylene glycol 200 solution and / or polyethylene glycol 400 solution.

[0012] As a further technical solution, the wetting agent in the core layer includes fatty alcohol polyoxyethylene ether and / or polyester modified polydimethylsiloxane solution.

[0013] The wetting agent in the immediate-release layer includes organosilicon wetting agent ZY-8131 and / or organosilicon wetting agent ZY-2014.

[0014] To facilitate rapid disintegration and the formation of a suspension in the core layer, a polar wetting agent, fatty alcohol polyoxyethylene ether and / or polyester-modified polydimethylsiloxane solution, is used to adhere to the microparticles (humic acid) based on the principle of "like dissolves like." This polar wetting agent significantly reduces the surface tension of the core layer microparticles, promoting dispersion in water and allowing the disintegrant to function more effectively. Furthermore, to ensure the stability and aesthetic appearance of the entire small-particle dry suspension, a silicone-based wetting agent is used in the immediate-release layer, which reduces surface tension and improves surface gloss.

[0015] Since the density of the prepared dry suspension is greater than that of water, and the macro-elements are also readily soluble, there is no need to coat the surface of the immediate release layer with a wetting agent.

[0016] As a further technical solution, the mass concentration of sodium silicate in the polyethylene glycol solution is 20%~30%.

[0017] As a further technical solution, the core layer comprises the following components in parts by weight: 200-400 parts lignite, 10-15 parts disintegrant, 7-10 parts dispersant, 20-40 parts wetting agent, and 30-50 parts first binder;

[0018] The immediate-release layer comprises the following components: 40-60 parts of nitrogen source, 50-60 parts of phosphorus source, 50-80 parts of potassium source, 5-10 parts of wetting agent, and 3-8 parts of second binder.

[0019] As a further technical solution, the disintegrant includes one or more of dry starch, carboxymethyl starch, and sodium sulfate.

[0020] As a further technical solution, the dispersant includes one or more of sodium dodecylbenzenesulfonate, carboxymethyl cellulose, and polyethylene ether.

[0021] As a further technical solution, the nitrogen source includes urea;

[0022] The phosphorus source includes monoammonium phosphate and / or diammonium phosphate;

[0023] The potassium source includes potassium sulfate and / or potassium chloride.

[0024] As a further technical solution, the mass ratio of the lignite to the first binder is 20:3~5.

[0025] This invention also proposes a method for preparing a small-particle dry suspension containing lignite and nutrients, comprising the following steps:

[0026] S1. Mix and dry lignite, disintegrant, dispersant and first binder to obtain a mixture;

[0027] S2. The mixture is mixed with a wetting agent while being dried to obtain the core layer;

[0028] S3. The core layer is mixed with nitrogen source, phosphorus source, potassium source, wetting agent and second binder while drying to obtain a small particle dry suspension containing lignite and nutrients.

[0029] As a further technical solution, the mixing speed in S1 is 100~200 rpm, and the drying temperature is 100~110℃.

[0030] As a further technical solution, the mixing speed in S2 is 100~200 rpm, and the drying temperature is 70~80℃.

[0031] As a further technical solution, the mixing speed in S3 is 80~150 rpm, and the drying temperature is 60~80℃.

[0032] The working principle and beneficial effects of this invention are as follows:

[0033] 1. In order to fully utilize the role of humic acid and coal gangue in lignite, this invention provides a small-particle dry suspension agent, which enables coal gangue and free humic acid to form a suspension in water. This not only fully improves the utilization rate of lignite, prevents soil compaction, enriches the soil, and increases crop yield and income, but also greatly reduces costs and labor in use and transportation, making it convenient to use and transport.

[0034] 2. The free humic acid and coal gangue in the core layer of the small particle dry suspension of the present invention have good effects on slow-release stimulation of crops and soil improvement, respectively. The quick-release layer uses a large number of elements that plants can directly absorb as raw materials to provide necessary nutrients for crop growth and ensure nutritional balance during crop growth.

[0035] 3. The small-particle dry suspension of the present invention comprises a core layer and an immediate-release layer. The core layer is mainly composed of lignite, with microparticles having a particle size of approximately 0.5-1.5 mm. The immediate-release layer consists of macroelements encapsulated around the core layer, forming small particles with a particle size of approximately 1.5-2.5 mm. The core layer and the immediate-release layer are mainly composed of organic and inorganic substances, respectively. Different binders are used for the core layer and the immediate-release layer based on the different properties of these substances. The binder for the core layer includes hydroxymethyl bisphenol A epoxy resin and / or epoxy resorcinol formaldehyde resin, while the binder for the immediate-release layer is a polyethylene glycol solution of sodium silicate. This achieves optimal performance in use while maintaining stability and aesthetic appeal. Furthermore, the binder for the immediate-release layer not only provides essential elements for plant growth (silicates) but also acts as a binder, reducing costs and simplifying the granulation process.

[0036] 4. In the small-particle dry suspension of this invention, the free humic acid and coal gangue in the core layer mainly stimulate crops and improve soil. The core layer disintegrates in water and, through the action of the dispersant, remains suspended in water without settling. Furthermore, a layer of macronutrients is coated on the surface of the wetting agent in the core layer, forming a quick-release layer. This layer serves two main purposes: first, it prevents moisture absorption by the core layer, protecting it, as the disintegrant added to the core layer will automatically disintegrate upon moisture absorption, forming an air-isolated protective film through the quick-release layer; second, it provides nutrients to crops, supplying the necessary nitrogen, phosphorus, and potassium to meet the growth needs of different crops, maximizing the nutrient requirements of early-stage crops to improve crop yield and quality.

[0037] 5. In the small-particle dry suspension of the present invention, the core layer is granulated using the principle of thermosetting. The covalent bonds of the macromolecular humic acid branch chain and the covalent bonds of the thermosetting polymer binder break and recombine at high temperature. Therefore, the microparticles of the core layer bond quickly, are not easy to disintegrate automatically, and are not easy to shed powder, which greatly improves the stability of the core layer and provides a guarantee for the encapsulation of the subsequent quick-release layer. Detailed Implementation

[0038] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0039] The properties of the raw materials in the following examples and comparative examples are as follows:

[0040] The lignite is a black raw coal. According to the method in GB / T 11957-2001 "Determination of Humic Acid Yield in Coal", the total humic acid content was measured to be 57.38 wt%, the free humic acid content was 55.94 wt%, and the coal gangue content was 12.47 wt%. It was purchased from Shandong Mugeng Ecological Agriculture Technology Co., Ltd.

[0041] The dry starch is corn starch, product number CGSL025482, white powder, purchased from Hebei Jinfeng Starch Sugar Alcohol Co., Ltd.

[0042] The parameters of the hydroxymethyl bisphenol A epoxy resin are as follows: the model of the hydroxymethyl bisphenol A epoxy resin is BE188, the solid content is 75wt%, the viscosity is 200~300cP, it is colorless and transparent, and it was purchased from Tiantai High-tech Technology Co., Ltd.

[0043] The parameters of epoxy resorcinol formaldehyde resin are as follows: the product number of epoxy resorcinol formaldehyde resin is CGSL023270, the solid content is 75wt%, the color is light yellow, the viscosity is 200~300cP, and it was purchased from Shandong Chengtian Chemical Co., Ltd.

[0044] The product number of the fatty alcohol polyoxyethylene ether is CGSL023246. It is a liquid with a weight-average molecular weight of 400-600 and an active ingredient content of 99wt%. It was purchased from Shandong Weilun Chemical Co., Ltd.

[0045] The parameters of the polyester-modified polydimethylsiloxane solution are as follows: The polyester-modified polydimethylsiloxane solution is model KMT-5540, liquid, with an effective ingredient content of 95wt%, purchased from Foshan Kening New Materials Co., Ltd.

[0046] Example 1

[0047] S1. Weigh 200 parts of 200-mesh lignite, 10 parts of dry starch, 7 parts of sodium dodecylbenzenesulfonate, and 30 parts of hydroxymethyl bisphenol A epoxy resin into a round pot. Adjust the pot speed to 100 rpm and the drying temperature to 100℃. Mix for 45 min. Then add 20 parts of fatty alcohol polyoxyethylene ether and adjust the speed to 200 rpm and the drying temperature to 70℃. Mix for 10 min to obtain a core layer of 0.5~1.5 mm.

[0048] S2. Weigh out 40 parts of 100-mesh urea, 50 parts of monoammonium phosphate, 50 parts of potassium sulfate, 3 parts of 25wt% sodium silicate-polyethylene glycol 200 solution and 5 parts of organosilicon wetting agent ZY-8131 and put them into a round pot. Adjust the speed of the round pot to 80 rpm and the drying temperature to 60℃. Mix for 60 minutes and then stop to obtain a small particle dry suspension agent of 1.5~2.5mm.

[0049] Example 2

[0050] S1. Weigh 300 parts of 200-mesh lignite, 11 parts of carboxymethyl starch, 8 parts of carboxymethyl cellulose and 40 parts of epoxy resorcinol formaldehyde resin and put them into a round pot. Adjust the speed of the round pot to 150 rpm and the drying temperature to 110℃. After mixing for 50 min, add 30 parts of polyester modified polydimethylsiloxane solution and adjust the speed to 100 rpm and the drying temperature to 80℃. Mix for 10 min to obtain a core layer of 0.5~1.5 mm.

[0051] S2. Weigh out 50 parts of 100-mesh urea, 60 parts of diammonium phosphate, 60 parts of potassium chloride, 5 parts of 30wt% sodium silicate-polyethylene glycol 200 solution and 6 parts of organosilicon wetting agent ZY-2014 and put them into a round pot. Adjust the speed of the round pot to 90 rpm and the drying temperature to 70℃. Mix for 70 minutes and then stop to obtain a small particle dry suspension agent of 1.5~2.5mm.

[0052] Example 3

[0053] S1. Weigh 400 parts of 200-mesh lignite, 12 parts of sodium sulfate, 9 parts of polyethylene ether, and 50 parts of epoxy resorcinol formaldehyde resin into a round pot. Adjust the pot speed to 200 rpm and the drying temperature to 110℃. After mixing for 55 min, add 40 parts of fatty alcohol polyoxyethylene ether and adjust the speed to 100 rpm and the drying temperature to 70℃. Mix for 10 min to obtain a core layer of 0.5~1.5 mm.

[0054] S2. Weigh out 60 parts of 100-mesh urea, 50 parts of diammonium phosphate, 70 parts of potassium sulfate, 8 parts of 20wt% sodium silicate-polyethylene glycol 400 solution and 7 parts of organosilicon wetting agent ZY-2014 and put them into a round pot. Adjust the speed of the round pot to 100 rpm and the drying temperature to 80℃. Mix for 80 minutes and then stop to obtain a small particle dry suspension agent of 1.5~2.5mm.

[0055] Example 4

[0056] S1. Weigh 200 parts of 200-mesh lignite, 13 parts of carboxymethyl starch, 9 parts of carboxymethyl cellulose and 50 parts of hydroxymethyl bisphenol A epoxy resin and put them into a round pot. Adjust the speed of the round pot to 200 rpm and the drying temperature to 100℃. After mixing for 60 min, add 40 parts of polyester-modified polydimethylsiloxane solution and adjust the speed to 200 rpm and the drying temperature to 70℃. Mix for 10 min to obtain a core layer of 0.5~1.5 mm.

[0057] S2. Weigh out 60 parts of 100-mesh urea, 60 parts of monoammonium phosphate, 40 parts of potassium sulfate, 40 parts of potassium chloride, 5 parts of 25wt% sodium silicate-polyethylene glycol 400 solution, and 8 parts of organosilicon wetting agent ZY-8131 and put them into a round pot. Adjust the speed of the round pot to 120 rpm and the drying temperature to 70℃. Mix for 70 minutes and then stop to obtain a small particle dry suspension agent of 1.5~2.5mm.

[0058] Example 5

[0059] S1. Weigh 300 parts of 200-mesh lignite, 14 parts of carboxymethyl starch, 9 parts of carboxymethyl cellulose and 30 parts of epoxy resorcinol formaldehyde resin and put them into a round pot. Adjust the speed of the round pot to 150 rpm and the drying temperature to 105℃. After mixing for 45 min, add 20 parts of polyester modified polydimethylsiloxane solution and adjust the speed to 200 rpm and the drying temperature to 70℃. Mix for 10 min to obtain a core layer of 0.5~1.5 mm.

[0060] S2. Weigh out 50 parts of 100-mesh urea, 60 parts of monoammonium phosphate, 80 parts of potassium sulfate, 4 parts of 30wt% sodium silicate-polyethylene glycol 200 solution and 10 parts of organosilicon wetting agent ZY-8131 and put them into a round pot. Adjust the speed of the round pot to 150 rpm and the drying temperature to 70℃. Mix for 100 minutes and then stop to obtain a small particle dry suspension agent of 1.5~2.5mm.

[0061] Example 6

[0062] S1. Weigh 400 parts of 200-mesh lignite, 15 parts of sodium sulfate, 10 parts of polyethylene ether, and 50 parts of epoxy resorcinol formaldehyde resin and place them in a round pot. Adjust the pot rotation speed to 200 rpm and the drying temperature to 110℃. After mixing for 60 min, add 40 parts of polyester-modified polydimethylsiloxane solution, adjust the rotation speed to 200 rpm, and the drying temperature to 80℃. Mix for 10 min to obtain a core layer of 0.5~1.5 mm.

[0063] S2. Weigh out 60 parts of 100-mesh urea, 60 parts of diammonium phosphate, 80 parts of potassium chloride, 7 parts of 20wt% sodium silicate-polyethylene glycol 400 solution and 10 parts of organosilicon wetting agent ZY-2014 and put them into a round pot. Adjust the speed of the round pot to 150 rpm and the drying temperature to 80℃. Mix for 120 minutes and then stop to obtain a small particle dry suspension agent of 1.5~2.5mm.

[0064] Example 7

[0065] S1. Weigh 200 parts of 200-mesh lignite, 10 parts of dry starch, 7 parts of sodium dodecylbenzenesulfonate and 30 parts of epoxy resorcinol formaldehyde resin and put them into a round pot. Adjust the pot speed to 100 rpm and the drying temperature to 100℃. After mixing for 45 min, add 20 parts of fatty alcohol polyoxyethylene ether and adjust the speed to 200 rpm and the drying temperature to 70℃. Mix for 10 min to obtain a core layer of 0.5~1.5 mm.

[0066] S2. Weigh out 40 parts of 100-mesh urea, 50 parts of monoammonium phosphate, 50 parts of potassium sulfate, 3 parts of 25wt% sodium silicate-polyethylene glycol 200 solution and 5 parts of organosilicon wetting agent ZY-8131 and put them into a round pot. Adjust the speed of the round pot to 80 rpm and the drying temperature to 60℃. Mix for 60 minutes and then stop to obtain a small particle dry suspension agent of 1.5~2.5mm.

[0067] Example 8

[0068] S1. Weigh 200 parts of 200-mesh lignite, 10 parts of dry starch, 7 parts of sodium dodecylbenzenesulfonate, and 40 parts of hydroxymethyl bisphenol A epoxy resin into a round pot. Adjust the pot speed to 100 rpm and the drying temperature to 100℃. Mix for 45 min. Then add 20 parts of fatty alcohol polyoxyethylene ether and adjust the speed to 200 rpm and the drying temperature to 70℃. Mix for 10 min to obtain a core layer of 0.5~1.5 mm.

[0069] S2. Weigh out 40 parts of 100-mesh urea, 50 parts of monoammonium phosphate, 50 parts of potassium sulfate, 3 parts of 25wt% sodium silicate-polyethylene glycol 200 solution and 5 parts of organosilicon wetting agent ZY-8131 and put them into a round pot. Adjust the speed of the round pot to 80 rpm and the drying temperature to 60℃. Mix for 60 minutes and then stop to obtain a small particle dry suspension agent of 1.5~2.5mm.

[0070] Example 9

[0071] S1. Weigh 200 parts of 200-mesh lignite, 10 parts of dry starch, 7 parts of sodium dodecylbenzenesulfonate and 50 parts of hydroxymethyl bisphenol A epoxy resin and put them into a round pot. Adjust the speed of the round pot to 100 rpm and the drying temperature to 100℃. After mixing for 45 min, add 20 parts of fatty alcohol polyoxyethylene ether and adjust the speed to 200 rpm and the drying temperature to 70℃. Mix for 10 min to obtain a core layer of 0.5~1.5 mm.

[0072] S2. Weigh out 40 parts of 100-mesh urea, 50 parts of monoammonium phosphate, 50 parts of potassium sulfate, 3 parts of 25wt% sodium silicate-polyethylene glycol 200 solution and 5 parts of organosilicon wetting agent ZY-8131 and put them into a round pot. Adjust the speed of the round pot to 80 rpm and the drying temperature to 60℃. Mix for 60 minutes and then stop to obtain a small particle dry suspension agent of 1.5~2.5mm.

[0073] Example 10

[0074] S1. Weigh 200 parts of 200-mesh lignite, 10 parts of dry starch, 7 parts of sodium dodecylbenzenesulfonate, and 30 parts of hydroxymethyl bisphenol A epoxy resin into a round pot. Adjust the pot rotation speed to 100 rpm and the drying temperature to 100℃. After mixing for 45 minutes, add 20 parts of organosilicon wetting agent ZY-8131 and adjust the rotation speed to 200 rpm and the drying temperature to 70℃. Mix for 10 minutes to obtain a core layer of 0.5~1.5 mm.

[0075] S2. Weigh out 40 parts of 100-mesh urea, 50 parts of monoammonium phosphate, 50 parts of potassium sulfate, 3 parts of 25wt% sodium silicate-polyethylene glycol 200 solution and 5 parts of organosilicon wetting agent ZY-8131 and put them into a round pot. Adjust the speed of the round pot to 80 rpm and the drying temperature to 60℃. Mix for 60 minutes and then stop to obtain a small particle dry suspension agent of 1.5~2.5mm.

[0076] Example 11

[0077] S1. Weigh 200 parts of 200-mesh lignite, 10 parts of dry starch, 7 parts of sodium dodecylbenzenesulfonate, and 30 parts of hydroxymethyl bisphenol A epoxy resin into a round pot. Adjust the pot speed to 100 rpm and the drying temperature to 100℃. Mix for 45 min. Then add 20 parts of fatty alcohol polyoxyethylene ether and adjust the speed to 200 rpm and the drying temperature to 70℃. Mix for 10 min to obtain a core layer of 0.5~1.5 mm.

[0078] S2. Weigh out 40 parts of 100-mesh urea, 50 parts of monoammonium phosphate, 50 parts of potassium sulfate, 3 parts of 25wt% sodium silicate-polyethylene glycol 200 solution and 5 parts of fatty alcohol polyoxyethylene ether and put them into a round pot. Adjust the speed of the round pot to 80 rpm and the drying temperature to 60℃. Mix for 60 minutes and then stop to obtain a small particle dry suspension agent of 1.5~2.5mm.

[0079] Comparative Example 1

[0080] 200 parts of 200-mesh lignite, 10 parts of dry starch, 7 parts of sodium dodecylbenzenesulfonate, 30 parts of hydroxymethyl bisphenol A epoxy resin, 20 parts of fatty alcohol polyoxyethylene ether, 40 parts of 100-mesh urea, 50 parts of monoammonium phosphate, 50 parts of potassium sulfate, 3 parts of 25wt% sodium silicate-polyethylene glycol 200 solution, and 5 parts of organosilicon wetting agent ZY-8131 were weighed and mechanically stirred for 1 hour to obtain a small particle dry suspension.

[0081] Comparative Example 2

[0082] Weigh out 200 parts of 200-mesh lignite, 10 parts of dry starch, 7 parts of sodium dodecylbenzenesulfonate, and 30 parts of hydroxymethyl bisphenol A epoxy resin and place them in a round pot. Adjust the speed of the round pot to 100 rpm and the drying temperature to 100℃. After mixing for 45 minutes, add 20 parts of fatty alcohol polyoxyethylene ether and adjust the speed to 200 rpm and the drying temperature to 70℃. Mix for 10 minutes to obtain a small particle dry suspension.

[0083] Comparative Example 3

[0084] Weigh out 40 parts of 100-mesh urea, 50 parts of monoammonium phosphate, 50 parts of potassium sulfate, 3 parts of 25wt% sodium silicate-polyethylene glycol 200 solution and 5 parts of organosilicon wetting agent ZY-8131 and put them into a round pot. Adjust the pot rotation speed to 80 rpm and the drying temperature to 60℃. Mix for 60 minutes and then stop to obtain a small particle dry suspension.

[0085] Comparative Example 4

[0086] S1. Weigh 200 parts of 200-mesh lignite, 10 parts of dry starch, 7 parts of sodium dodecylbenzenesulfonate and 30 parts of hydroxymethyl bisphenol A epoxy resin respectively and put them into a round pot. Adjust the speed of the round pot to 100 rpm and the drying temperature to 100℃. After mixing for 45 minutes, a core layer of 0.5~1.5 mm is obtained.

[0087] S2. Weigh out 40 parts of 100-mesh urea, 50 parts of monoammonium phosphate, 50 parts of potassium sulfate, 3 parts of 25wt% sodium silicate-polyethylene glycol 200 solution and 5 parts of organosilicon wetting agent ZY-8131 and put them into a round pot. Adjust the speed of the round pot to 80 rpm and the drying temperature to 60℃. Mix for 60 minutes and then stop to obtain a small particle dry suspension agent of 1.5~2.5mm.

[0088] Performance testing:

[0089] Five g of the small-particle dry suspension obtained in Examples 1-11 and Comparative Examples 1-4 were placed in soil with vermiculite as the main material, and three Chinese cabbage seeds were scattered in each seed. The seeds were cultivated under the same conditions (temperature: 25℃, humidity: 50%). The germination time of the Chinese cabbage was recorded, and the average weight of each Chinese cabbage seed after 20 days (average of 3 seeds) was recorded. The suspension rate was tested according to the method in GB / T 14825-2006. The results are recorded in Table 1.

[0090] Table 1. Germination time, average weight after 20 days, and suspension rate of bok choy

[0091]

[0092] As shown in Table 1, the blank sample had the longest germination time. Compared to Comparative Example 1, Comparative Example 1 directly mixed all components evenly, and the germination time was the same as that of Example 1. This indicates that the small-particle dry suspension prepared by this invention did not affect the effects of lignite and macronutrients. The effect of mixing macronutrients required for the immediate-release layer was greater than that of the lignite microparticle core layer, meaning that nitrogen, phosphorus, and potassium had a better promoting effect on the early germination of pakchoi. However, after 20 days, the average weight of each pakchoi in Comparative Example 1 was lower than that in Example 1, indicating that the small-particle dry suspension provided by this invention is more effective in promoting plant growth.

[0093] Compared with Comparative Examples 2 and 3, Comparative Example 2 only had a core layer and Comparative Example 3 only had a quick-release layer. The germination time of the bok choy in Example 1 was shorter than that in Comparative Examples 2 and 3. After 20 days, the average quality of each four-season bok choy was better than that in Comparative Examples 2 and 3, indicating that the effect of small particle dry suspension is significantly better than the use of lignite and macro-elements alone.

[0094] The suspension rates of the small-particle dry suspensions obtained in Examples 1-6 were all greater than 94%, indicating that the present invention successfully prepared a small-particle dry suspension containing lignite and nutrients. In Comparative Example 4, when the core layer lacked a wetting agent, the suspension rate decreased because the core layer is insoluble in water, sinks quickly in water, and has a short contact time with water, preventing the disintegrant from fully exerting its effect.

[0095] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A small-particle dry suspension containing lignite and nutrients, characterized in that, Includes a core layer and a quick-release layer; The core layer comprises the following components: lignite, disintegrant, dispersant, wetting agent, and first binder; The immediate-release layer comprises the following components: nitrogen source, phosphorus source, potassium source, wetting agent, and second binder; The first adhesive comprises hydroxymethyl bisphenol A epoxy resin and / or epoxy resorcinol formaldehyde resin; The second adhesive is a polyethylene glycol solution of sodium silicate; The preparation method includes the following steps: S1. Mix and dry lignite, disintegrant, dispersant and first binder to obtain a mixture; S2. The mixture is mixed with a wetting agent while being dried to obtain the core layer; S3. The core layer is mixed with nitrogen source, phosphorus source, potassium source, wetting agent and second binder while drying to obtain a small particle dry suspension containing lignite and nutrients.

2. The small-particle dry suspension agent containing lignite and nutrients according to claim 1, characterized in that, The polyethylene glycol solution includes polyethylene glycol 200 solution and / or polyethylene glycol 400 solution.

3. The small-particle dry suspension agent containing lignite and nutrients according to claim 1, characterized in that, The wetting agent in the core layer includes fatty alcohol polyoxyethylene ether and / or polyester-modified polydimethylsiloxane solution. The wetting agent in the immediate-release layer includes organosilicon wetting agent ZY-8131.

4. The small-particle dry suspension agent containing lignite and nutrients according to claim 1, characterized in that, The sodium silicate in the polyethylene glycol solution has a mass concentration of 20% to 30%.

5. The small-particle dry suspension agent containing lignite and nutrients according to claim 1, characterized in that, The core layer comprises the following components in parts by weight: 200-400 parts lignite, 10-15 parts disintegrant, 7-10 parts dispersant, 20-40 parts wetting agent, and 30-50 parts first binder; The immediate-release layer comprises the following components: 40-60 parts of nitrogen source, 50-60 parts of phosphorus source, 50-80 parts of potassium source, 5-10 parts of wetting agent, and 3-8 parts of second binder.

6. The small-particle dry suspension agent containing lignite and nutrients according to claim 1, characterized in that, The disintegrant includes one or more of dry starch, carboxymethyl starch, and sodium sulfate.

7. The small-particle dry suspension agent containing lignite and nutrients according to claim 1, characterized in that, The dispersant includes one or more of sodium dodecylbenzenesulfonate, carboxymethyl cellulose, and polyethylene ether.

8. The small-particle dry suspension agent containing lignite and nutrients according to claim 1, characterized in that, The nitrogen source includes urea; the phosphorus source includes monoammonium phosphate and / or diammonium phosphate; and the potassium source includes potassium sulfate and / or potassium chloride.

9. A small-particle dry suspension agent containing lignite and nutrients according to claim 1, characterized in that, The mass ratio of lignite to the first binder is 20:3~5.

10. A method for preparing a small-particle dry suspension containing lignite and nutrients according to any one of claims 1 to 9, characterized in that, Includes the following steps: S1. Mix and dry lignite, disintegrant, dispersant and first binder to obtain a mixture; S2. The mixture is mixed with a wetting agent while being dried to obtain the core layer; S3. The core layer is mixed with nitrogen source, phosphorus source, potassium source, wetting agent and second binder while drying to obtain a small particle dry suspension containing lignite and nutrients.

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