Severe saline-alkali soil modifier and preparation method thereof

Abstract

The invention discloses a severe saline-alkali soil improver and a preparation method of the severe saline-alkali soil improver. The fertilizer comprises the following components in parts by weight: ardealite, citric acid residue, dry green grass, lobster shell, rape seed cake, ryegrass, fly ash, silica sol and trace element fertilizer, and the additive is composed of humic acid, a microbial agent and an acidic fertilizer, and the preparation method comprises the following steps: a) formula adjustment; b) preparing raw materials; c) pretreating the raw materials; and d) adding materials. The main component of phosphogypsum is calcium sulfate, the principle is that sodium ions adsorbed on soil colloid are replaced by calcium ions, when gypsum is dissolved in soil water, a large number of calcium ions can be released to be subjected to exchange reaction with the surface of the soil colloid, so that the exchangeable sodium content of soil is reduced, the soil colloid is soluble salt, and the soil colloid is easy to dissolve. The soil can be leached out in the irrigation or rainfall process, so that the salinity and alkalinity of the soil are reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of heavy saline-alkali land improvers, and specifically relates to a heavy saline-alkali land improver and a preparation method thereof. Background Art

[0002] According to the patent disclosed on the Chinese Patent Network, the patent name is: A special soil improver for heavy saline-alkali land and its preparation and application, and the patent number is: CN116554885A. The present invention discloses a special improver for heavy saline-alkali land. The improver includes wood vinegar liquid, chelated calcium, plant hormones, and ammonia water. Through the screening of raw materials and the optimization of the preparation method, the finally obtained saline-alkali land improver is a brownish-red liquid. The preparation method is simple, environmentally friendly, and easy to operate. This saline-alkali soil improver is not only applicable to light and medium saline-alkali land, but when used for heavy saline-alkali land, it can significantly reduce the soil pH value and total salt content, simultaneously displace harmful sodium ions, improve soil fertility, promote the formation of soil aggregate structure, improve the soil structure, increase the crop emergence rate of saline-alkali soil, and promote the healthy growth of crops in obstacle soil, thereby increasing crop yields.

[0003] However, the above-mentioned configuration method of the saline-alkali land improver is simple, and it cannot play the role of the improver according to the levels of heavy saline-alkali land during use, reducing the effect of the improver. Summary of the Invention

[0004] To solve the problems raised in the above background art, the purpose of the present invention is to provide a heavy saline-alkali land improver and a preparation method thereof, which have the advantage of high adaptability and solve the problem that the improver cannot play its role according to the levels of heavy saline-alkali land.

[0005] To achieve the above purpose, the present invention provides the following technical solution: A heavy saline-alkali land improver and a preparation method thereof, the improver is composed of the following raw materials in parts by weight; phosphogypsum, citric acid residue, dry grass, lobster shell, rapeseed cake, ryegrass, fly ash, silica sol, trace element fertilizer.

[0006] Preferably, the additive is composed of humic acid, microbial inoculum, and acidic fertilizer.

[0007] Preferably, it includes step a) formula adjustment; step b) raw material preparation: step c) pretreatment of raw materials; step d) adding materials; step e) removing moisture; step f) packaging treatment;

[0008] Step a) formula adjustment; Determine the formula of the improver according to the severity of the saline-alkali land and the application requirements.

[0009] Step b) Prepare raw materials; Prepare the required raw materials, select natural gypsum with higher purity or industrial by-product gypsum, such as phosphogypsum. For natural gypsum, impurities such as soil and stones need to be removed; for phosphogypsum, it needs to be pretreated to remove harmful impurities such as phosphorus and fluorine.

[0010] Step c) Pretreat raw materials; Phosphogypsum screening machine: Used to remove large particle impurities in phosphogypsum, such as stones and unreacted phosphate rock. Common ones are vibrating screening machines. By vibrating, the material moves on the screen, and particles of different particle sizes are separated according to the aperture size of the screen. The aperture of the screen can be selected according to needs, such as two to ten millimeters.

[0011] Sand washer; Adopt the method of water washing. Utilize the scouring and stirring action of water to separate impurities such as fine sand in phosphogypsum. Its working principle is that the motor drives the impeller to rotate, so that water and phosphogypsum are fully stirred in the water tank, and then the impurities and phosphogypsum are separated by precipitation or overflow.

[0012] Neutralization equipment: If phosphogypsum contains acidic impurities, such as phosphoric acid, a neutralization equipment can be used. Use a stirring reaction kettle and add an appropriate amount of alkaline substance such as lime for neutralization reaction. There is a stirring device in the reaction kettle to ensure that the neutralization reaction proceeds fully. The stirring speed is generally thirty to sixty revolutions per minute, and the reaction temperature can be controlled at about normal temperature to fifty degrees Celsius according to the actual situation.

[0013] Step d) Add materials; Horizontal screw ribbon mixer: Suitable for uniformly mixing phosphogypsum with other additives such as humic acid, microbial inoculant, acidic fertilizer, citric acid residue, dry grass, lobster shell, rapeseed cake, ryegrass, fly ash, silica sol and trace element fertilizer, etc. Its working principle is that through the rotation of the screw ribbon, the material makes complex movements in the machine body to achieve full mixing. The mixing time is generally ten to thirty minutes, and the rotation speed is twenty to forty revolutions per minute.

[0014] Extrusion granulator: Use pressure to extrude the mixed material through a die into particles. For the saline-alkali land conditioner containing phosphogypsum, if the material has a certain viscosity, its working pressure can be adjusted between one and ten megapascals according to the properties of the material and the requirements of particle size.

[0015] Step e) Remove moisture; Rotary dryer: Through the countercurrent or cocurrent contact of hot air and the material, the moisture in the material is evaporated. The rotation speed of the rotary drum is generally three to eight revolutions per minute, and the temperature of the hot air can be adjusted between eighty and one hundred and fifty degrees Celsius according to the properties of the material and the drying requirements.

[0016] Step f) Packaging process; Automatic quantitative packaging machine: It can package the modifier according to the set weight, with relatively high packaging accuracy, and the error is generally between plus or minus five percent and plus or minus two percent. The packaging materials can be plastic woven bags, paper bags or plastic film bags, which are selected according to the nature and usage requirements of the modifier.

[0017] Preferably in the present invention, the humic acid is an organic macromolecular compound, which contains acidic functional groups such as carboxyl groups and phenolic hydroxyl groups. These functional groups can undergo neutralization reactions with alkaline substances in the soil. At the same time, humic acid can improve the aggregate structure of the soil, increase the water and fertilizer retention capacity of the soil, adsorb sodium ions in the soil, reduce the toxic effect of sodium ions on plants, and promote the aggregation of soil colloids through its colloidal properties, thereby improving the physical structure of the soil.

[0018] Preferably in the present invention, the microbial inoculum is a preparation containing various beneficial microorganisms, such as Bacillus and Pseudomonas. These microorganisms have various action mechanisms in the soil. Some microorganisms can produce organic acids, such as lactic acid and acetic acid. These organic acids can lower the pH value of the soil. At the same time, the microorganisms can decompose organic substances in the soil, increase the humus content in the soil, and improve the soil structure. In addition, some microorganisms can promote the absorption of nutrients by plant roots, form a symbiotic relationship with plant roots, and enhance the stress resistance of plants.

[0019] Preferably in the present invention, for the acidic fertilizer modifier, its composition and principle: Acidic fertilizers such as superphosphate and ammonium sulfate. The main components of superphosphate are calcium dihydrogen phosphate and calcium sulfate. After hydrolysis, calcium dihydrogen phosphate will produce acidity, and the produced phosphoric acid can neutralize the alkalinity in the soil. Ammonium sulfate hydrolyzes in the soil to produce acidity, thereby lowering the pH value of the soil, and the ammonium ions therein can displace sodium ions on the soil colloid.

[0020] Preferably in the present invention, the production of citric acid is generally achieved through microbial fermentation. Taking Aspergillus niger fermenting corn starch as an example, first, the corn starch is hydrolyzed into glucose, and then Aspergillus niger ferments glucose to produce citric acid under suitable temperature (about 28 to 32 °C), pH value (4.5 to 5.5) and aeration conditions.

[0021] Preferably in the present invention, the silica sol is prepared by hydrolysis and polycondensation reactions of a silicon source under acidic or alkaline conditions. Under acidic conditions, the hydrolyzed silicic acid will further undergo polycondensation reactions. By controlling reaction conditions such as temperature, pH value, and reactant concentration, silica sols with different particle sizes and properties can be obtained.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0023] The main component of phosphogypsum in the present invention is calcium sulfate. The principle is to replace the sodium ions adsorbed on the soil colloid through calcium ions. When gypsum dissolves in soil water, a large amount of calcium ions will be released and undergo an exchange reaction with the surface of the soil colloid, thereby reducing the exchangeable sodium content of the soil. The soil colloid is a soluble salt and can be leached out of the soil during irrigation or rainfall, thereby reducing the salinity of the soil. Detailed implementation mode

[0024] The following will combine the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work belong to the scope of protection of the present invention.

[0025] A heavy saline-alkali land conditioner and its preparation method provided by the present invention, the conditioner is composed of the following raw materials in parts by weight; 120-180 parts of phosphogypsum, 250-400 parts of citric acid residue, 160-200 parts of dry grass, 120-160 parts of lobster shell, 80-120 parts of rapeseed cake, 30-60 parts of ryegrass, 8-20 parts of fly ash, 800-1200 parts of silica sol, and 10-14 parts of trace element fertilizer.

[0026] The present invention is further arranged such that the additive is composed of humic acid, microbial inoculum and acidic fertilizer.

[0027] The present invention is further arranged to include step a) formulation adjustment; step b) preparing raw materials: step c) pre-treating raw materials; step d) adding materials; step e) removing moisture; step f) packaging treatment;

[0028] Step a) Formulation adjustment; Determine the formulation of the conditioner according to the severity of the saline-alkali land and application requirements;

[0029] Step b) Preparing raw materials; Prepare the required raw materials, select natural gypsum or industrial by-product gypsum with higher purity, such as phosphogypsum. For natural gypsum, impurities such as soil and stones need to be removed; for phosphogypsum, it needs to be pre-treated to remove harmful impurities such as phosphorus and fluorine;

[0030] Step c) Pre-treating raw materials; Phosphogypsum screening machine: used to remove large particle impurities in phosphogypsum, such as stones and unreacted phosphate rock. Common ones are vibrating screening machines. Through vibration, the material moves on the screen, and particles of different particle sizes are separated according to the aperture size of the screen. The aperture size of the screen can be selected according to needs, such as two to ten millimeters;

[0031] Sand washer: It adopts the water washing method and uses the scouring and stirring action of water to separate impurities such as fine sand in phosphogypsum. Its working principle is that the motor drives the impeller to rotate, making the water and phosphogypsum fully stirred in the water tank, and then separating the impurities and phosphogypsum by precipitation or overflow.

[0032] Neutralization equipment: If phosphogypsum contains acidic impurities such as phosphoric acid, a neutralization equipment can be used. A stirring reaction kettle is used, and an appropriate amount of alkaline substance such as lime is added for neutralization reaction. A stirring device is provided in the reaction kettle to ensure full progress of the neutralization reaction. The stirring speed is generally 30 to 60 revolutions per minute, and the reaction temperature can be controlled at about normal temperature to 50 degrees Celsius according to the actual situation.

[0033] Step d) Adding materials; Horizontal screw ribbon mixer: It is suitable for evenly mixing phosphogypsum with other additives such as humic acid, microbial inoculum, acidic fertilizer, citric acid residue, dry grass, lobster shell, rapeseed cake, ryegrass, fly ash, silica sol and trace element fertilizer, etc. Its working principle is that through the rotation of the screw ribbon, the materials make complex movements in the machine body to achieve full mixing. The mixing time is generally 10 to 30 minutes, and the rotation speed is 20 to 40 revolutions per minute.

[0034] Extrusion granulator: It uses pressure to extrude the mixed materials through a die into particles. For the saline-alkali land conditioner containing phosphogypsum, if the materials have a certain viscosity, its working pressure can be adjusted between 1 and 10 MPa according to the properties of the materials and the requirements of particle size.

[0035] Step e) Removing moisture; Rotary dryer: Through the countercurrent or cocurrent contact of hot air and materials, the moisture in the materials is evaporated. The rotation speed of the rotary drum is generally 3 to 8 revolutions per minute, and the temperature of the hot air can be adjusted between 80 and 150 degrees Celsius according to the properties of the materials and the drying requirements.

[0036] Step f) Packaging treatment; Automatic quantitative packaging machine: It can package the conditioner according to the set weight, with high packaging accuracy. The error is generally between plus or minus 5% and plus or minus 2%. The packaging materials can be plastic woven bags, paper bags or plastic film bags, which are selected according to the properties and usage requirements of the conditioner.

[0037] The present invention is further set as that humic acid is an organic macromolecular compound, which contains acidic functional groups such as carboxyl group and phenolic hydroxyl group. These functional groups can undergo neutralization reactions with alkaline substances in the soil. At the same time, humic acid can improve the aggregate structure of the soil, increase the water retention and fertilizer retention capacity of the soil. It can adsorb sodium ions in the soil, reduce the toxic effect of sodium ions on plants, and through its colloid characteristics, promote the aggregation of soil colloids and improve the physical structure of the soil.

[0038] The present invention is further configured such that the microbial inoculant is a preparation containing various beneficial microorganisms, such as Bacillus, Pseudomonas, etc. These microorganisms have various action mechanisms in the soil. Some microorganisms can produce organic acids, such as lactic acid, acetic acid, etc. These organic acids can reduce the pH value of the soil. At the same time, the microorganisms can decompose the organic matter in the soil, increase the humus content in the soil, and improve the soil structure. In addition, some microorganisms can promote the absorption of nutrients by plant roots, form a symbiotic relationship with plant roots, and enhance the stress resistance of plants.

[0039] The present invention is further configured such that for the acidic fertilizer conditioner, its components and principle: acidic fertilizers such as superphosphate, ammonium sulfate, etc. The main components of superphosphate are calcium dihydrogen phosphate and calcium sulfate. Among them, calcium dihydrogen phosphate will hydrolyze to produce acidity after hydrolysis, and the generated phosphoric acid can neutralize the alkalinity in the soil. Ammonium sulfate hydrolyzes in the soil to produce acidity, thereby reducing the pH value of the soil, and the ammonium ions therein can displace the sodium ions on the soil colloid.

[0040] The present invention is further configured such that the production of citric acid is generally achieved through microbial fermentation. Taking Aspergillus niger fermenting corn starch as an example, first, the corn starch is hydrolyzed into glucose, and then Aspergillus niger ferments glucose to produce citric acid under suitable temperature (about 28 to 32 degrees Celsius), pH value (4.5 to 5.5), and aeration conditions.

[0041] The present invention is further configured such that the silica sol is prepared through the hydrolysis and polycondensation reactions of a silicon source under acidic or alkaline conditions. Under acidic conditions, the hydrolyzed silicic acid will further undergo a polycondensation reaction. By controlling reaction conditions, such as temperature, pH value, reactant concentration, etc., silica sols with different particle sizes and properties can be obtained.

[0042] The working principle and usage process of the present invention: When in use, first preselect materials, preferably phosphogypsum. Then process it. Through vibration, the phosphogypsum moves on the sieve, and particles of different particle sizes are separated according to the sieve aperture size. Then, adopt the method of washing with water. Utilize the scouring and stirring effects of water to separate impurities such as fine sand in the phosphogypsum. If the phosphogypsum contains acidic impurities, such as phosphoric acid, a neutralization device can be used. Use a stirring reaction kettle and add an appropriate amount of alkaline substance such as lime for neutralization reaction. Then uniformly mix the treated phosphogypsum with other additives such as humic acid, microbial inoculant, acidic fertilizer, citric acid residue, dry grass, lobster shell, rapeseed cake, ryegrass, fly ash, silica sol, and trace element fertilizer, etc. After mixing is completed, use an extrusion granulator to extrude the mixed material through a mold under pressure into particles. Then remove the moisture from the particles. Use a rotary dryer to make hot air contact with the material in a countercurrent or cocurrent manner to evaporate the moisture in the material. Finally, perform packaging treatment; Automatic quantitative packaging machine: It can package the conditioner according to the set weight and transport it to saline-alkali land for treatment.

[0043] In summary, for the preparation method of the heavy saline-alkali land conditioner, by using phosphogypsum, citric acid residue, dry grass, lobster shell, rapeseed cake, ryegrass, silica sol and trace element fertilizer in combination, the problem that the existing conditioner cannot play its role according to the levels of heavy saline-alkali land is solved.

[0044] It should be noted that in this text, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device.

[0045] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A heavy saline-alkali land conditioner, characterized in that; The modifier is composed of the following raw materials in parts by weight: 120-180 parts of phosphogypsum, 250-400 parts of citric acid residue, 160-200 parts of dry grass, 120-160 parts of lobster shell, 80-120 parts of rapeseed cake, 30-60 parts of ryegrass, 8-20 parts of fly ash, 800-1200 parts of silica sol, and 10-14 parts of trace element fertilizer.

2. The soil conditioner for severely saline-alkali land according to claim 1, characterized in that: The additive is composed of humic acid, microbial inoculum, and acidic fertilizer.

3. The preparation method of a severe saline-alkali land conditioner according to any one of claims 1-2, characterized in that: It includes step a) formula adjustment; step b) raw material preparation: step c) raw material pretreatment; step d) material addition; step e) moisture removal; step f) packaging treatment; Step a) formula adjustment; Determine the formula of the modifier according to the severity of the saline-alkali land and application requirements. Step b) raw material preparation; Prepare the required raw materials, select natural gypsum or industrial by-product gypsum with higher purity, such as phosphogypsum. For natural gypsum, impurities such as soil and stones need to be removed; for phosphogypsum, it needs to be pretreated to remove harmful impurities such as phosphorus and fluorine. Step c) raw material pretreatment; Phosphogypsum screening machine: Used to remove large particle impurities in phosphogypsum, such as stones and unreacted phosphate rock. Common ones are vibrating screening machines. Through vibration, the material moves on the screen, and particles of different particle sizes are separated according to the aperture size of the screen. The aperture of the screen can be selected according to needs, such as two to ten millimeters; Sand washer; Adopt the water washing method. Utilize the scouring and stirring action of water to separate impurities such as fine sand in phosphogypsum. Its working principle is that the motor drives the impeller to rotate, so that water and phosphogypsum are fully stirred in the water tank, and then the impurities and phosphogypsum are separated by precipitation or overflow; Neutralization equipment: If phosphogypsum contains acidic impurities such as phosphoric acid, a neutralization equipment can be used. Use a stirring reaction kettle and add an appropriate amount of alkaline substance such as lime for neutralization reaction. There is a stirring device in the reaction kettle to ensure the full progress of the neutralization reaction. The stirring speed is generally 30 to 60 revolutions per minute, and the reaction temperature can be controlled at about normal temperature to 50 degrees Celsius according to the actual situation; Step d) material addition; Horizontal screw ribbon mixer: Suitable for evenly mixing phosphogypsum with other additives such as humic acid, microbial inoculum, acidic fertilizer, citric acid residue, dry grass, lobster shell, rapeseed cake, ryegrass, fly ash, silica sol, and trace element fertilizer, etc. Its working principle is that through the rotation of the screw ribbon, the material makes complex movements in the machine body to achieve full mixing. The mixing time is generally 10 to 30 minutes, and the rotation speed is 20 to 40 revolutions per minute; Extrusion granulator: Use pressure to extrude the mixed material through a mold into particles. For the saline-alkali land modifier containing phosphogypsum, if the material has a certain viscosity, its working pressure can be adjusted between 1 and 10 MPa according to the properties of the material and the requirements of particle size; Step e) moisture removal; Rotary dryer: Through the countercurrent or cocurrent contact of hot air with the material, the moisture in the material is evaporated. The rotation speed of the rotary drum is generally 3 to 8 revolutions per minute, and the temperature of the hot air can be adjusted between 80 and 150 degrees Celsius according to the properties of the material and the drying requirements; Step f) Packaging process; Automatic quantitative packaging machine: It can package the conditioner according to the set weight, with relatively high packaging accuracy, and the error is generally between plus or minus five percent and plus or minus two percent. The packaging materials can be plastic woven bags, paper bags or plastic film bags, which are selected according to the properties and usage requirements of the conditioner.

4. The preparation method of a severe saline-alkali land conditioner according to claim 3, characterized in that: The humic acid is an organic macromolecular compound that contains acidic functional groups such as carboxyl groups and phenolic hydroxyl groups. These functional groups can undergo neutralization reactions with alkaline substances in the soil. At the same time, humic acid can improve the aggregate structure of the soil, increase the water and fertilizer retention capacity of the soil. It can adsorb sodium ions in the soil, reduce the toxicity of sodium ions to plants, and through its colloid characteristics, promote the aggregation of soil colloids and improve the physical structure of the soil.

5. The preparation method of a heavy saline-alkali soil conditioner according to claim 3, characterized in that: The microbial inoculant is a preparation containing various beneficial microorganisms, such as Bacillus and Pseudomonas. These microorganisms have various action mechanisms in the soil. Some microorganisms can produce organic acids, such as lactic acid and acetic acid. These organic acids can reduce the pH value of the soil. At the same time, the microorganisms can decompose organic substances in the soil, increase the humus content in the soil, and improve the soil structure. In addition, some microorganisms can promote the absorption of nutrients by plant roots, and enhance the stress resistance of plants by forming a symbiotic relationship with plant roots.

6. The preparation method of a severe saline-alkali land conditioner according to claim 3, characterized in that: The acidic fertilizer conditioner, composition and principle: Acidic fertilizers such as superphosphate and ammonium sulfate. The main components of superphosphate are calcium dihydrogen phosphate and calcium sulfate. After hydrolysis, calcium dihydrogen phosphate will produce acidity, and the generated phosphoric acid can neutralize the alkalinity in the soil. Ammonium sulfate hydrolyzes in the soil to produce acidity, thereby reducing the pH value of the soil, and the ammonium ions therein can displace sodium ions on the soil colloid.

7. The preparation method of a heavy saline-alkali soil conditioner according to claim 3, characterized in that: The production of citric acid is generally achieved through microbial fermentation. Taking the fermentation of corn starch by Aspergillus niger as an example, first, corn starch is hydrolyzed into glucose, and then Aspergillus niger ferments glucose to produce citric acid under suitable temperature (about 28 to 32 degrees Celsius), pH value (4.5 to 5.5) and aeration conditions.

8. The preparation method of a heavy saline-alkali land conditioner according to claim 3, characterized in that: The silica sol is prepared by the hydrolysis and polycondensation reaction of a silicon source under acidic or alkaline conditions. Under acidic conditions, the hydrolyzed silicic acid will further undergo a polycondensation reaction. By controlling reaction conditions such as temperature, pH value, and reactant concentration, silica sols with different particle sizes and properties can be obtained.