Granular acid soil conditioner as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of preparation of soil conditioners, and particularly relates to a granular acid soil conditioner as well as a preparation method and application thereof. The granular acid soil conditioner prepared by taking wastes such as the plant ash, the ground phosphate rock and the alcohol production concentrated waste liquid as preparation raw materials and mixing bentonite, lime and the disintegrating agent according to a specific proportion is easy to disintegrate, can effectively improve acid soil, and has a quick-acting and lasting acid adjusting effect. Meanwhile, the granular acid soil conditioner can supplement medium trace elements in soil and promote plant growth. Furthermore, the granular soil conditioner is easier to realize mechanical operation in the application process, is more portable and is lower in cost. In addition, industrial and agricultural wastes can be fully utilized, resource utilization is realized, nutrient returning to the field is facilitated, and nutrient cyclic utilization is realized.

Description

Technical Field

[0001] The invention belongs to the technical field of soil conditioner preparation, and in particular relates to a granular acidic soil conditioner and a preparation method and application thereof. Background Art

[0002] Soil acidification refers to the process in which the soil absorptive complex receives a certain amount of exchangeable hydrogen ions or aluminum ions, causing the alkaline (base) ions in the soil to be leached away. The causes of soil acidification are as follows: large and concentrated precipitation, strong leaching, and a large loss of base ions such as potassium, calcium, and magnesium in the soil are the fundamental causes of soil acidification; in order to pursue yield and benefits, long-term and large-scale application of chemical fertilizers is an important cause of soil acidification; in addition, in general orchards, most farmers are accustomed to supplement nutrients such as calcium and magnesium by foliar spraying. The base ions such as calcium and magnesium in the soil are absorbed by plants and not supplemented in time, resulting in a serious imbalance of soil nutrients, leading to more serious soil acidification. When the soil is too acidic (pH < 5.0), toxic heavy metals such as manganese and aluminum will be activated into an effective state, poisoning plant roots, reducing yields, and seriously affecting economic benefits.

[0003] There are currently two main ways to improve acidic soil. One is to neutralize acid and alkali by using alkaline soil materials, such as wood ash and lime; the second is to apply organic fertilizer. However, when using the first method to improve acidic soil, soil acidification improvement in large bases requires a large amount of wood ash, and wood ash often needs to be obtained from biomass power plants. However, due to the light texture of wood ash, it needs to be bagged during transportation, which has high transportation costs. It is also easy to be blown away by the wind when applied, and there is a lot of dust, which leads to low enthusiasm for use. The application of lime only increases the calcium content in the soil, and the application amount is not easy to control. Long-term use can easily cause soil compaction. When using the second method to improve acidic soil, the effect of investing a small amount of organic fertilizer in plots with high soil acidity is minimal, and a large amount of organic fertilizer needs to be invested. However, investing a large amount of organic fertilizer will undoubtedly increase the planting cost, and the effect of improving soil acidity by investing organic fertilizer is slow.

[0004] In addition to the above two methods of improving acidic soil, there are many acidic soil conditioners on the market for improving acidic soil, and there are various types of acidic soil conditioners. However, the soil improvement effects of current acidic soil conditioners vary. Some acidic soil conditioners are granulated for easy transportation and application, but their production process is complicated and the price is relatively high. The most important thing is that the particle disintegration effect is poor, which greatly reduces the effect. Summary of the invention

[0005] The object of the present invention is to provide a granular acidic soil conditioner and a preparation method and application thereof. The granular acidic soil conditioner is easy to disintegrate and can effectively regulate acidic soil, and the preparation process is simple and easy to operate.

[0006] The invention provides a granular acidic soil conditioner, comprising the following raw materials in parts by weight: 20 to 30 parts of plant ash, 30 to 60 parts of phosphate rock powder, 10 to 20 parts of concentrated waste liquid from alcohol production, 10 to 20 parts of bentonite, 2 to 10 parts of lime and 0 to 5 parts of a disintegrant.

[0007] Preferably, the particle size of the granular acidic soil conditioner is 0.3 to 5 mm.

[0008] Preferably, the method for preparing the concentrated waste liquid from alcohol production comprises: evaporating and concentrating the waste liquid after fermentation to produce alcohol until a liquid with a water content of 50% is formed to obtain the concentrated waste liquid from alcohol production.

[0009] Preferably, the pH value of the alcohol production concentrated waste liquid is 4.0-5.0.

[0010] Preferably, the pH value of the bentonite is 8-9.

[0011] The present invention also provides a method for preparing the granular acidic soil conditioner described in the above technical solution, comprising the following steps:

[0012] Mix and dissolve the lime with water to obtain a viscous lime-water mixture;

[0013] The pH value of the lime-water viscous mixture is adjusted to 7.0-7.5 with concentrated waste liquid from alcohol production to obtain a viscous mixture of alcohol waste liquid-lime-water;

[0014] Mixing wood ash, phosphate rock powder, bentonite and disintegrator to obtain a first mixture;

[0015] Mixing the alcohol waste liquid-lime-water viscous mixture with the first mixture in a spraying manner to obtain a second mixture;

[0016] The second mixture is granulated to obtain the granular acidic soil conditioner.

[0017] Preferably, the granulation method includes roller extrusion granulation.

[0018] Preferably, after the granulation, the granular acidic soil conditioner is further dried to obtain a finished granular acidic soil conditioner.

[0019] The present invention also provides the use of the granular acidic soil conditioner described in the above technical solution or the granular acidic soil conditioner prepared by the preparation method described in the above technical solution in improving acidic soil and / or promoting plant growth.

[0020] Preferably, the promoting plant growth includes promoting plant root growth.

[0021] Beneficial effects:

[0022] The present invention provides a granular acidic soil conditioner, comprising the following raw materials by mass: 20-30 parts of plant ash, 30-60 parts of phosphate rock powder, 10-20 parts of concentrated waste liquid from alcohol production, 10-20 parts of bentonite, 2-10 parts of lime and 0-5 parts of disintegrant. The granular acidic soil conditioner prepared by the present invention using waste materials such as plant ash, phosphate rock powder and concentrated waste liquid from alcohol production as raw materials, and mixing bentonite, lime and disintegrant in a specific proportion is easy to disintegrate, can effectively improve acidic soil, and the acidification effect is fast and lasting. At the same time, the granular acidic soil conditioner can supplement the trace elements in the soil and promote plant growth. Furthermore, the granular soil conditioner is easier to realize mechanized operation during application, is more portable and has lower cost. In addition, the present invention can make full use of industrial and agricultural wastes, realize resource utilization, facilitate the return of nutrients such as potassium, calcium and silicon in the raw materials of the soil conditioner to the field, and realize nutrient recycling. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required to be used in the embodiments are briefly introduced below.

[0024] Figure 1 This is a flow chart for preparing the granular acidic soil conditioner in Example 1;

[0025] Figure 2 This is a phenotype diagram of the granular acidic soil conditioner in Example 1;

[0026] Figure 3 This is a display effect diagram of the beginning of the soil conditioner disintegration test in Test Example 1;

[0027] Figure 4 This is a display effect diagram after the soil conditioner disintegration test in Test Example 1 is completed;

[0028] Figure 5 This is a finished product display diagram of soil conditioner 1 in test example 1;

[0029] Figure 6 This is a finished product display diagram of soil conditioner 2 in test example 1;

[0030] Figure 7 This is a finished product display diagram of the granular acidic soil conditioner in Example 1 in Test Example 1;

[0031] Figure 8 This is a diagram showing the disintegration effect of the soil conditioner 1 after the disintegration test in Test Example 1 was carried out for two hours;

[0032] Fig. 9 This is a diagram showing the disintegration effect of soil conditioner 2 after the disintegration test in test example 1 was carried out for two hours;

[0033] Fig.10 This is a diagram showing the disintegration effect of the granular acidic soil conditioner in Example 1 after the disintegration test in Test Example 1 was carried out for two hours;

[0034] Fig.11 This is a diagram showing the overall effects of the three soil conditioners after the disintegration test in Test Example 1 was carried out for two hours;

[0035] Fig.12 This is a diagram showing the root growth effect of spreading the granular acidic soil conditioner in Example 1 in the flat plate root promotion effect test in Test Example 2;

[0036] Fig.13 This is a diagram showing the root growth effect of the control in the flat plate root promotion effect test in Test Example 2;

[0037] Fig.14 This is a diagram showing the field test base for the granular acidic soil conditioner in Test Example 3;

[0038] Fig.15 The growth of banana roots in the field test of Test Example 3 using the granular acidic soil conditioner prepared in Example 1;

[0039] Fig.16 The growth of banana roots in the field test control in Test Example 3;

[0040] Fig.17 This is the root phenotype diagram after 21 days of cultivation in Test Example 5;

[0041] Fig.18 This is a scan of the root system after 21 days of cultivation in Test Example 5;

[0042] Fig.19 This is a graph showing the pH value changes of soil physical and chemical indicators of different soil conditioners in Test Example 6;

[0043] Fig. 20 This is a graph showing the results of measuring the changes in soil physical and chemical indicators and organic matter of different soil conditioners in Test Example 6;

[0044] Fig.21 This is a graph showing the results of the determination of changes in soil physicochemical indicators of alkaline nitrogen using different soil conditioners in Test Example 6;

[0045] Fig. 22 This is a graph showing the change in available phosphorus in soil physical and chemical indicators of different soil conditioners in Test Example 6;

[0046] Fig.23This is a graph showing the change in available potassium in soil physical and chemical indicators of different soil conditioners in Test Example 6;

[0047] Fig.24 This is a graph showing the change in EC values ​​of soil physical and chemical indicators of different soil conditioners in Test Example 6;

[0048] Fig.25 This is a graph showing the change in effective calcium in soil physical and chemical indicators of different soil conditioners in Test Example 6;

[0049] Fig.26 This is a graph showing the change in effective magnesium in soil physical and chemical indicators of different soil conditioners in Test Example 6;

[0050] Fig. 27 This is a graph showing the changes in effective silicon in soil physical and chemical indicators of different soil conditioners in Test Example 6. DETAILED DESCRIPTION

[0051] The invention provides a granular acidic soil conditioner, comprising the following raw materials in parts by weight: 20 to 30 parts of plant ash, 30 to 60 parts of phosphate rock powder, 10 to 20 parts of concentrated waste liquid from alcohol production, 10 to 20 parts of bentonite, 2 to 10 parts of lime and 0 to 5 parts of a disintegrant.

[0052] In terms of weight, the granular acidic soil conditioner of the present invention includes 20-30 parts of wood ash; as an embodiment, the weight of the wood ash is 20-25 parts; as an embodiment, the wood ash of the present invention is derived from waste from a biomass power plant, the wood ash is light and alkaline, has the effect of quickly adjusting the acidity of the soil and disinfecting the soil, and also contains potassium and various trace elements required by plants.

[0053] The granular acidic soil conditioner of the present invention comprises 30 to 60 parts of phosphate rock powder; as an embodiment, the mass fraction of the phosphate rock powder is 40 to 55 parts. As another embodiment, the mass fraction of the phosphate rock powder is 47 to 50 parts. The particle size of the phosphate rock powder of the present invention can be 200 to 300 meshes. The phosphate rock powder of the present invention is an industrial solid waste generated during the mining and beneficiation of phosphate ore, which is alkaline and contains a large amount of silicon, calcium and magnesium elements required for the formation of plant and soil colloids.

[0054] As an implementation mode, the mass ratio of the phosphate rock powder and the wood ash of the present invention can be 2.0 to 3.0; at this ratio, it can ensure that the alkaline substances in the particles can quickly adjust the acidity, and the hardness and disintegration of the particles can also be ensured.

[0055] The granular acidic soil conditioner of the present invention comprises 10 to 20 parts of concentrated waste liquid from alcohol production; as an embodiment, the mass fraction of the concentrated waste liquid from alcohol production is 15 to 18 parts. As an embodiment, the preparation method of the concentrated waste liquid from alcohol production of the present invention comprises: evaporating and concentrating the waste liquid after fermentation to produce alcohol until a liquid with a water content of 50% is formed to obtain the concentrated waste liquid from alcohol production. As an embodiment, the waste liquid after fermentation to produce alcohol of the present invention can be a waste liquid obtained by extracting alcohol from sugarcane molasses as a carbon source and fermenting alcohol with brewer's yeast. As an embodiment, the pH value of the concentrated waste liquid from alcohol production is 4.0 to 5.0. The concentrated waste liquid from alcohol production of the present invention contains certain nutrients and functional substances such as potassium humate, amino acids and microbial active factors, and has an obvious effect on promoting plant growth; in addition, the carbon-containing small molecule organic matter formed by the decomposition of the macromolecular substance brewer's yeast after fermentation and the polysaccharide substance produced by microbial metabolism in the concentrated waste liquid from alcohol production have good viscosity and can be used as a binder. Unlike other adhesives, the viscous substances in the concentrated waste liquid of alcohol production have a small molecular weight. After encountering water, the particles quickly absorb water under the capillary action of the disintegrant, and the viscous substances in the concentrated waste liquid of alcohol production quickly dissolve with water, reducing viscosity. At the same time, the disintegrant in the particles also begins to expand rapidly after absorbing water, further accelerating the disintegration of the particles. On the contrary, the molecular weight of the adhesives used in conventional granulation in this field is generally large, and the speed at which the adhesives dissolve in water is also relatively slow. After some adhesives are dissolved in water, their viscosity increases instead of decreasing, and the particles are difficult to disintegrate under the action of the expansion of the disintegrant.

[0056] The granular acidic soil conditioner of the present invention comprises 10 to 20 parts of bentonite; as an embodiment, the mass fraction of the bentonite is 10 to 15. As an embodiment, the pH value of the bentonite of the present invention can be 8 to 9. The bentonite of the present invention is a soil conditioner with a pH value of 8 to 9, and has a strong cation exchange capacity and adsorption capacity. It can passivate heavy metals and retain water and fertilizer in the soil. It can also be used as a particle adhesive in granulation to increase the granulation rate of granulation. The bentonite has a large specific surface area, strong adsorption capacity, good bonding force, small shrinkage, and will not produce cracks after drying. As an embodiment, the selection of the amount of bentonite additive of the present invention has the following considerations: it is not advisable to add too much bentonite to the particles. Adding too much bentonite will firstly reduce the particle disintegration rate and the nutrient application is too slow. Second, the addition of too much bentonite will increase the cost of raw materials.

[0057] The granular acidic soil conditioner of the present invention comprises 2 to 10 parts of lime; as an embodiment, the mass fraction of the lime is 2 to 5 parts. The lime of the present invention has the function of adjusting the pH of the concentrated waste liquid of alcohol production, avoiding the effect of acid-base neutralization when the concentrated waste liquid of alcohol is mixed with other raw materials, thereby causing the pH of the finished product to be reduced too much and the finished product to be quickly acidified.

[0058] The granular acidic soil conditioner of the present invention includes 0 to 5 parts of a disintegrant; as an embodiment, the mass fraction of the disintegrant is 0.2 to 1 part. As an embodiment, the disintegrant of the present invention can be any one or more of sodium carboxymethyl starch, low-substituted cellulose, cross-linked polyvinyl pyrrolidone (cross-linked PVP), cross-linked sodium carboxymethyl cellulose, microcrystalline cellulose, and a highly absorbent resin. The function of the disintegrant of the present invention is to promote the rapid fragmentation of large particle matter into fine molecular matter, so that the active ingredient is quickly released and exerts its effect. As an embodiment, the disintegration mechanism of the disintegrant of the present invention is one or more of the following: (1) capillary action, that is, the disintegrant forms capillary channels in the particles that are easy to wet. When the particles are placed in water, water can quickly enter the particles through the capillaries, making the entire particles moist and disintegrating; (2) swelling effect: the disintegrant itself has a strong water absorption and swelling property. After absorbing water and swelling, the binding force of the particles is disintegrated. The greater the swelling rate, the more significant the disintegration efficiency; (3) wetting effect: when some substances dissolve in water, heat is generated, thereby expanding the air remaining in the particles and promoting disintegration; (4) gas generation effect: gas is generated by chemical reaction, and the particles are disintegrated with the help of the expansion of the gas.

[0059] As an embodiment, the sum of the masses of the raw materials in the granular acidic soil conditioner of the present invention is 100 parts, that is, in terms of mass percentage, the sum of the mass percentage of the raw materials in the granular acidic soil conditioner is 100%.

[0060] As an embodiment, the particle size of the granular acidic soil conditioner of the present invention is 0.3 to 5 mm.

[0061] The present invention uses industrial and agricultural waste as the main raw materials, fully utilizes resources, has low cost, combines the characteristics of the raw materials themselves, and scientifically proportions them. Starting from the essence of soil improvement, the soil improvement effect is rapid and lasting, and it also has the function of providing nutrients, thereby realizing the recycling of nutrients.

[0062] The present invention also provides a method for preparing the granular acidic soil conditioner described in the above technical solution, comprising the following steps:

[0063] Mix and dissolve the lime with water to obtain a viscous lime-water mixture;

[0064] The pH value of the lime-water viscous mixture is adjusted to 7.0-7.5 with concentrated waste liquid from alcohol production to obtain a viscous mixture of alcohol waste liquid-lime-water;

[0065] Mixing wood ash, phosphate rock powder, bentonite and disintegrator to obtain a first mixture;

[0066] Mixing the alcohol waste liquid-lime-water viscous mixture with the first mixture in a spraying manner to obtain a second mixture;

[0067] The second mixture is granulated to obtain the granular acidic soil conditioner.

[0068] As an embodiment, when the lime is mixed with water to dissolve in the present invention, the amount of water used is not particularly limited, as long as the purpose of dissolving the lime is achieved.

[0069] As an embodiment, the advantage of mixing the alcohol waste liquid-lime-water viscous mixture with the first mixture by spraying is to avoid the mixture from forming balls due to excessive moisture in some areas during mixing, which affects the uniformity of the material. The spray parameters of the present invention are not particularly limited, and the conventional spray parameters in the art can be used.

[0070] As an embodiment, the granulation method of the present invention can be double-roll extrusion granulation, that is, extrusion granulation is performed using a double-roll extrusion granulator.

[0071] As an embodiment, after the granulation of the present invention, the soil conditioner after granulation is screened to obtain the granular acidic soil conditioner. As an embodiment, the particle size of the granular acidic soil conditioner of the present invention is 0.3-5 mm. As an embodiment, the present invention recycles the particles with a sieved particle size less than 0.3 mm and re-granulates them to make full use of resources.

[0072] As an embodiment, after the screening, the present invention further includes drying the granular acidic soil conditioner to obtain a granular acidic soil conditioner finished product. The drying parameters of the present invention are not particularly limited, and conventional drying parameters in the art can be used.

[0073] After granulation and drying, the present invention forms particles due to the binding force generated by the sticky substance (the concentrated waste liquid of alcohol production and the sticky bentonite). The particles after drying have low water content and strong water absorption capacity. During the water absorption process, the concentrated waste liquid dissolves in water, eliminating part of the binding force. At the same time, the binding force is further eliminated under the action of the bentonite and disintegrant absorbing water and swelling, so that the particles are easier to disintegrate.

[0074] The granular acidic soil conditioner prepared by the preparation method of the present invention has the functions of adjusting soil pH, providing nutrients and promoting crop growth.

[0075] The present invention also provides the use of the granular acidic soil conditioner described in the above technical solution or the granular acidic soil conditioner prepared by the preparation method described in the above technical solution in improving acidic soil and / or promoting plant growth. As an embodiment, the pH value of the acidic soil described in the present invention can be 8-12. As an embodiment, the promoting plant growth described in the present invention can be promoting the growth of plant roots.

[0076] In order to further illustrate the present invention, the technical solution provided by the present invention is described in detail below in conjunction with the accompanying drawings and embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0077] Example 1

[0078] A granular acidic soil conditioner, composed of the following raw materials in percentage by mass:

[0079] 20% wood ash, 47.7% phosphate rock powder, 10% bentonite, 20% concentrated waste liquid from alcohol production, 2% lime and 0.3% disintegrant;

[0080] Plant ash is waste from biomass power plants, in fine powder form, with a pH of 10 to 12; phosphate rock powder is the waste residue left after high-temperature extraction of phosphate fertilizer, which is crushed to 300 mesh by a grinder and has a pH of 10 to 11. The preparation method of concentrated waste liquid from alcohol production is to further evaporate the water of the waste liquid remaining after producing alcohol using sugarcane molasses as a carbon source to 50%, and the brix is ​​55°Bx. The disintegrant is specifically a highly absorbent resin.

[0081] The preparation method of the above-mentioned granular acidic soil conditioner is as follows: dissolving lime in an appropriate amount of water, stirring well to form a viscous liquid, and obtaining mixture 1; slowly adding mixture 1 to concentrated waste liquid from alcohol production, adjusting the pH to 7.0-7.5, and obtaining mixture 2; putting plant ash, phosphate rock powder, bentonite, and disintegrant into a vessel with a stirrer and mixing well to obtain mixture 3; adding mixture 2 to mixture 3 in the form of a spray, stirring well to obtain mixture 4, wherein the moisture content of mixture 4 is controlled to be 11-13%; extruding and sieving mixture 4 through a double-roll extrusion granulator to obtain particles with a particle size of 0.3-5 mm, namely mixture 5; drying mixture 5 through a drying device at 105°C for 30 minutes to obtain mixture 6, which is the granular acidic soil conditioner of the present invention. The specific flow chart is as follows Figure 1 shown.

[0082] The phenotype of the prepared granular acidic soil conditioner is shown in the figure Figure 2As shown (the actual particle size is 3-5 mm when the image was taken under magnification). Through testing, it was found that the pH of the granular acidic soil conditioner was 11.81, the particle hardness value was 26.3±2.9N, and the particle size was 3-5 mm.

[0083] Example 2

[0084] A granular acidic soil conditioner, composed of the following raw materials in percentage by mass:

[0085] 22.6% wood ash, 50% phosphate rock powder, 10% bentonite, 15% concentrated waste liquid from alcohol production, 2% lime and 0.4% disintegrant;

[0086] Plant ash is waste from biomass power plants, in fine powder form, with a pH of 10-12; phosphate rock powder is the waste residue left after the wet phosphoric acid method is used to extract phosphate fertilizer, which is crushed to 200 mesh by a grinder and has a pH of 7.59. The preparation method of concentrated waste liquid from alcohol production is to further evaporate the water of the waste liquid remaining after producing alcohol using sugarcane molasses as a carbon source to 50%, and the brix is ​​53°Bx. The disintegrant is specifically 0.35% of super absorbent resin and 0.05% of cross-linked polyvinyl pyrrolidone.

[0087] The preparation method of the above-mentioned granular acidic soil conditioner is as follows: wood ash, phosphate rock powder, bentonite and disintegrant are mixed according to the above-mentioned proportions, lime is mixed with concentrated waste liquid of alcohol production to adjust the pH value to 7.0-7.5, added in the form of spraying, fully mixed in a mixer, and the moisture content is controlled at 11-13%. The granular acidic soil conditioner is granulated by conveying it to a double-roll granulator through a conveyor belt, sieving it, and drying it at 105°C for 30 minutes to obtain the granular acidic soil conditioner. The test results show that the pH is 8.98, the particle hardness is 10.2±1.7N, and the particle size is 3-5mm.

[0088] Test Example 1

[0089] The granular acidic soil conditioner prepared in Example 1 was used to perform a disintegration test, and the steps are as follows:

[0090] Place a perforated gasket in a plastic cup filled with about 300 mL of tap water. Place 1.0 ± 0.2 g of soil conditioners of the same price and produced by different manufacturers into the cups. Figure 3 and Figure 4 They respectively represent the display effects at the beginning and after the disintegration test, where from left to right are soil conditioner 1 ( Figure 5 )、Soil conditioner 2( Figure 6 ) and the granular acidic soil conditioner (in a disintegrated state) prepared in Example 1 ( Figure 7 ), leave it for two hours to observe its disintegration effect ( Figures 8 to 11As shown), gently shake the plastic cup and estimate its disintegration rate based on the amount of soil conditioner above and below the perforated gasket, where disintegration rate (%) = percentage content of soil conditioner under the gasket / (percentage content of soil conditioner on the gasket + below the gasket) × 100%.

[0091] The main raw material of the soil conditioner 1 is plant ash, which is obtained by disc granulation and purchased in Meizhou City, Guangdong Province, and is called plant ash nutrient granular fertilizer;

[0092] The raw material of soil conditioner 2 is mainly wood ash, which is produced by extrusion granulation machine. Soil conditioner 2 was purchased from Guangxi Yuanlong Biotechnology Co., Ltd. and the product name is Weigenjiejie medium-element fertilizer.

[0093] Through experiments, the disintegration rates of soil conditioner 1, soil conditioner 2 and the granular acidic soil conditioner prepared in Example 1 were 35%, 0% and 90%, respectively. The disintegration effect of the granular acidic soil conditioner prepared in Example 1 met the requirements of the present invention for preparing the disintegrating acidic soil conditioner.

[0094] Test Example 2

[0095] The granular acidic soil conditioner prepared in Example 1 was used to conduct a flat plate root-promoting effect test, and the steps are as follows:

[0096] Acidic loess (pH 4.0) was used as the material. It was filled into a homemade plate (100×8×80mm), and 2g of granular acidic soil conditioner was evenly sprinkled on it, and then covered with 1cm thick soil (soil mass is about 150g). The control was not to sprinkle soil conditioner. The germinated cucumber seeds were buried in the surface layer. Three seeds were placed on each plate, and each treatment was repeated 3 times. They were placed in a climate incubator (daytime temperature 28℃, humidity 50%; nighttime temperature 25℃, humidity 80%) for cultivation, and watered and fertilized regularly. Observation was carried out after 10 days of cultivation. If Figures 12-13 shown.

[0097] Depend on Figures 12-13 It can be concluded that: when the soil particle amendment in Example 1 is used for comparison, in the same space, compared with the control group, there are visible differences in the number of roots and the thickness of the roots of the soil particle amendment in Example 1. The number of roots in the treatment group is larger and the roots are thicker, indicating that the soil particle amendment in Example 1 has a promoting effect on root growth.

[0098] Test Example 3

[0099] The granular acidic soil conditioner prepared in Example 1 was used for field testing, and the steps were as follows:

[0100] The test site is the Jincheng Agricultural Maliu Banana Base in Tanluo Town, Nanning City, Guangxi ( Fig.14), the test time was June 15, 2021, and 5 plants were randomly selected as test subjects. Each plant was buried with about 50g of the soil granule conditioner prepared in Example 1, which was recorded as the test group, and the rest were controls. The control group did not apply any soil conditioner, which was recorded as the control group. The same dose of fertilizer was applied to both the test group and the control group according to local planting habits. A follow-up visit was conducted on July 1 to observe the root system. Figures 15-16 shown.

[0101] Depend on Figures 15-16 It can be concluded that more lateral roots appeared near the roots in the fertilized area of ​​the granular acidic soil conditioner prepared in Example 1, while there were no obvious lateral roots in the control group, indicating that the application of the granular acidic soil conditioner prepared in Example 1 can promote the growth of plant roots.

[0102] Test Example 4

[0103] Verify the effect of different ratios of phosphate rock powder / wood ash on the disintegration of the prepared granular acidic soil conditioner:

[0104] The granular acidic soil conditioner was prepared according to the raw material composition and preparation method in Example 1, with the only difference being the adjustment of the mass ratio of phosphate rock powder / wood ash. The specific settings are shown in Table 1.

[0105] Table 1 Effects of different phosphate rock / wood ash mass ratios on the properties of granular acidic soil conditioners

[0106]

[0107] The disintegration and hardness of the prepared granular acidic soil conditioner were measured. The disintegration method was the same as that in Test Example 1. The hardness test method was to test the sample with a grain hardness tester. The maximum pressure value was the hardness value. The results are shown in Table 1.

[0108] It can be seen from Table 1 that too high a content of plant ash is not conducive to the disintegration of particles, and too high a content of phosphate rock powder leads to low particle hardness, which is easy to be crushed and not conducive to storage. Under the premise of ensuring disintegration, the appropriate ratio of phosphate rock powder to plant ash is 2 to 3.

[0109] Test Example 5

[0110] The experiment was conducted to verify the effect of different ratios of phosphate rock powder / wood ash on plant root morphology by conducting a flat plate root promotion experiment.

[0111] Powders with different phosphate rock / wood ash ratios were designed (① phosphate rock powder; ② wood ash; ③ phosphate rock powder:wood ash 2:1; ④ phosphate rock powder:wood ash 3:1).

[0112] Acidic loess (pH 4.3) was used as the material, and the field application rate was simulated at 500kg / mu (0.34g / kg). After being fully mixed, it was filled into a homemade flat plate (100×8×80mm). The amount of soil in the flat plate was about 150g / plate. Before the test, the loess was mixed with phosphate rock powder / wood ash (soil mass was about 150g). The control was no soil conditioner. The germinated cucumber seeds were buried in the surface layer. One seed was placed on each plate, and each treatment was repeated 3 times. It was placed in a climate incubator (daytime temperature 28°C, humidity 50%; nighttime temperature 25°C, humidity 80%) for cultivation, and watered and fertilized regularly. Root phenotype and scanning observations were carried out after 21 days of cultivation, such as Figures 17-18 , as shown in Table 2, where Fig.18 In the figure, (a) to (e) represent the cucumber root phenotypes in groups CK, ①, ②, ③, and ④, respectively.

[0113] Table 2 Effects of granular soil conditioners prepared from phosphate rock powder / wood ash at different dosage ratios on cucumber root growth

[0114]

[0115] Due to the low soil pH and low plant disease resistance, some treatments were easily infected with diseases during growth and died. Figures 17-18 From Table 2, it can be concluded that when the ratio of phosphate rock powder to wood ash is 3:1, the total root length, root surface area, number of root tips and number of root forks are all higher than those of phosphate rock powder; when the ratio of wood ash is 3:1, the overall trend is that the higher the content of phosphate rock powder, the better the root growth promotion effect.

[0116] Test Example 6

[0117] The granular acidic soil conditioner prepared in Example 1 was used for field testing, and the steps were as follows:

[0118] The test site is Jinjia Base, Natong Town, Nanning City, Guangxi. The test time is February 22, 2024. The test object is sugarcane (Guitang No. 44). Each treatment is selected for the test with an area of ​​4.8×10.0m2. 2The application amount was evenly spread on the surface, control 1 was without any soil conditioner, treatment 1 was the granular acidic soil conditioner prepared in Example 1, treatment 2 was potassium ash purchased from Guangxi Minhui Agricultural Technology Co., Ltd., and treatment 3 was a commercial soil conditioner purchased from Guangxi Yuanlong Biotechnology Co., Ltd., named agricultural matrix soil. Five days after the soil conditioner was spread, the soil was mixed and sown using a sugarcane seeder. Sampling began on March 4, 2024, and soil physical and chemical indicators were tracked regularly. The measured soil physical and chemical indicators included pH value, organic matter content, alkaline nitrogen content, effective phosphorus content, available potassium content, EC value, effective calcium content, effective magnesium content, and effective silicon content. The sampling soil was 5-10cm deep, about 10cm away from the sugarcane, and 5 points were mixed into one soil sample, with three replicates for each treatment. The results are as follows Figures 19 to 27 shown.

[0119] Depend on Figures 19 to 27 It can be concluded that the application of soil conditioners improves soil pH, available phosphorus, available potassium, available calcium, available magnesium and available silicon to varying degrees. After the application of acidic soil conditioners, soil pH is rapidly improved and the soil pH improvement effect is maintained for at least 6 months. Among them, the application of the granular acidic soil conditioner prepared in Example 1 improves soil available phosphorus, available magnesium and available silicon more significantly.

[0120] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention, not all of the embodiments. People can also obtain other embodiments based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A granular acidic soil conditioner, characterized in that: The method comprises the following raw materials in parts by weight: 20 to 30 parts of wood ash, 30 to 60 parts of phosphate rock powder, 10 to 20 parts of concentrated waste liquid from alcohol production, 10 to 20 parts of bentonite, 2 to 10 parts of lime and 0 to 5 parts of disintegrant.

2. The granular acidic soil conditioner according to claim 1, characterized in that: The particle size of the granular acidic soil conditioner is 0.3-5 mm.

3. The granular acidic soil conditioner according to claim 1, characterized in that: The method for preparing the concentrated waste liquid from alcohol production comprises: evaporating and concentrating the waste liquid after fermentation to produce alcohol until a liquid with a water content of 50% is formed to obtain the concentrated waste liquid from alcohol production.

4. The granular acidic soil conditioner according to claim 1 or 3, characterized in that: The pH value of the alcohol production concentrated waste liquid is 4.0-5.

0.

5. The granular acidic soil conditioner according to claim 1, characterized in that: The pH value of the bentonite is 8-9.

6. The method for preparing the granular acidic soil conditioner according to any one of claims 1 to 5, characterized in that: The steps include: Mix and dissolve the lime with water to obtain a viscous lime-water mixture; The pH value of the lime-water viscous mixture is adjusted to 7.0-7.5 with concentrated waste liquid from alcohol production to obtain a viscous mixture of alcohol waste liquid-lime-water; Mixing wood ash, phosphate rock powder, bentonite and disintegrator to obtain a first mixture; Mixing the alcohol waste liquid-lime-water viscous mixture with the first mixture in a spraying manner to obtain a second mixture; The second mixture is granulated to obtain the granular acidic soil conditioner.

7. The preparation method according to claim 6, characterized in that: The granulation method includes roller extrusion granulation.

8. The preparation method according to claim 6 or 7, characterized in that: After the granulation, the method further includes drying the granular acidic soil conditioner to obtain a finished granular acidic soil conditioner.

9. Use of the granular acidic soil conditioner according to any one of claims 1 to 5 or the granular acidic soil conditioner prepared by the preparation method according to any one of claims 6 to 8 in improving acidic soil and / or promoting plant growth.

10. The use according to claim 9, characterized in that: The promoting plant growth includes promoting the growth of plant roots.

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