Targeted alkali eliminating agent for soda saline-alkali soil as well as preparation method and use method of targeted alkali eliminating agent

Abstract

The invention provides a targeted alkali elimination agent for soda saline-alkali soil as well as a preparation method and a use method thereof, and belongs to the technical field of alkali elimination agents. The targeted alkali elimination agent for the soda saline-alkali soil is prepared from three functional components: an alkali elimination and dissolution promotion component, a reinforced substitution component and a flocculation and agglomeration component, the alkali-eliminating and dissolution-promoting component comprises citric acid and another component, and the another component is selected from at least one of amino acid, lactic acid and acetic acid; the reinforced substitution component is selected from at least one of calcium citrate, calcium monohydrogen citrate and calcium dihydrogen citrate; the flocculation and agglomeration component is selected from one of chitosan and chitin. The targeted alkali eliminating agent for soda saline-alkali soil can quickly and effectively reduce the pH value of soil and improve the granular structure content of the soil, and the saline-alkali soil physicochemical indexes such as porosity, water permeability and air permeability are obviously improved.

Description

Technical Field

[0001] The invention relates to the technical field of de-alkali agents, and in particular to a soda saline-alkali land targeted de-alkali agent and a preparation and use method thereof. Background Art

[0002] Salinized land is not only an obstacle to the construction of high-yield and stable-yield fields in my country's agricultural production, but also a huge land resource for the sustainable development of my country's agricultural production and national economy. At present, the improvement of saline-alkali land usually achieves certain results by applying base improvers to solve the problem of soil obstacles, but in actual large-scale improvement, there are problems such as salt return and uneven application, and the improvement effect is not ideal. Summary of the invention

[0003] The purpose of the present invention is to propose a soda saline-alkali land targeted de-alkali agent and a preparation and use method thereof, which can quickly and effectively reduce the soil pH value, increase the soil aggregate structure content, porosity, water permeability and other saline-alkali soil physical and chemical indicators are significantly improved.

[0004] The technical solution of the present invention is achieved in this way:

[0005] The invention provides a soda saline-alkali land targeted de-alkali agent, which consists of three functional components, namely, a de-alkali dissolution-promoting component, a flocculation and agglomeration component, and a strengthening and replacing component.

[0006] Alkali elimination and dissolution promoting components: Targeted alkali elimination, strengthening dissolution components, neutralizing OH in the soil - , lower soil pH, and promote the dissolution of metal ions. With citric acid, amino acids, lactic acid, acetic acid and other small molecular organic acids as the main components, rich in citric acid, amino acids and other organic acids can increase the solubility of sodium carbonate and sodium bicarbonate in the soil, accelerate the leaching and elution of salt ions and neutralize with carbonate and bicarbonate, and lower soil pH.

[0007] Flocculation and aggregation components: Promote soil flocculation, reduce soil erosion, and promote the formation of soil aggregate structure. With chitosan, chitin and other polysaccharides as the main components, it can improve soil structure, increase the number of aggregates, and improve the air permeability and water permeability of the soil. These substances aggregate suspended particles in the solution to form flocs through adsorption, bridging and electrical neutralization mechanisms.

[0008] Strengthening replacement component: Calcium-based sodium ion replacement component, the main components are organic calcium acids such as calcium citrate, calcium monohydrogen citrate, and calcium dihydrogen citrate. Free calcium ions (calcium citrate) can undergo a replacement reaction with sodium ions in saline-alkali soil to generate neutral substances that are easily soluble in water, thereby reducing the alkalinity of the soil. Under low pH conditions of 2.0-4.0, the solubility of calcium dihydrogen citrate is relatively high, reaching more than 5%.

[0009] The dry basis ratio of the effective ingredients of each component to the total mass of the product is 15-25% for the alkali-eliminating and dissolution-promoting component, 2-4% for the flocculation and agglomeration component, and 2-5% for the strengthening and replacing component.

[0010] The present invention further protects a method for preparing a targeted de-alkali agent for soda saline-alkali land, comprising the following steps:

[0011] The citric acid fermentation liquid is neutralized with calcium carbonate, the supernatant is filtered, concentrated 20-40 times, and the supernatant is filtered again to prepare the polysaccharide concentration of 3-5%. The polysaccharide solution can also be degraded by Aspergillus niger mycelium to form a 3-5% polysaccharide solution.

[0012] One or more of amino acids, lactic acid, acetic acid and other organic acids are mixed to obtain a mixed organic acid solution (dry basis content 20±5%), and 15-20 parts of citric acid (calculated as citric acid monohydrate) are added to 20-30 parts of the mixed organic acid solution to obtain a 50±5% concentration (dry basis) of alkali-eliminating and dissolving-promoting component. Alternatively, one or more of amino acids, lactic acid, acetic acid and other organic acids are added to a citric acid aqueous solution (including citric acid fermentation broth) at a suitable concentration to obtain a 50±5% concentration (dry basis) of alkali-eliminating and dissolving-promoting component.

[0013] Add 35-45 parts of alkali-eliminating and dissolving-promoting components to 50-60 parts of polysaccharide solution, compound the strengthening and replacing components, and add 1-5% calcium citrate (equivalent to Ca2+) according to the calcium content of the calcium salt after mixing. 2+ ions account for 1% of the final product), stir until completely dissolved, filter and then fill.

[0014] The present invention further protects a method for using a targeted de-alkali agent for soda saline-alkali land, comprising the following steps:

[0015] S1. Directional alkali and salt removal in paddy fields:

[0016] After rotary tillage, combine water harrowing and apply targeted alkali-removing agents at a rate of 50-100kg / mu. Keep the water layer on the field surface at 10cm. After standing for 2-3 days, drain the water after confirming the mud has settled, and quickly reduce the alkali and salt. Depending on the degree of salinity, 1-2 salt removal and alkali washing should be completed before rice transplanting. After the targeted alkali-removing agent is applied, water harrowing is used to promote full mixing of the alkali-reducing agent and the soil, rapid reaction, lowering the pH, and dissolving salt. The polysaccharide component accelerates the soil sedimentation rate. After standing, the soil can settle quickly, reducing soil and nutrient loss.

[0017] S2. Methods for reducing alkali and controlling salt in the critical period of rice:

[0018] Apply the targeted alkali-eliminating agent at 10-30 kg / mu each time during the rice greening, tillering, booting and filling stages. By continuously applying the targeted alkali-eliminating agent, the salinity stress caused by soil salt and alkali during planting can be reduced, and the soil conditioner and organic fertilizer can be fully mixed with the soil, nutrients can be increased, pH can be reduced, and the soil improvement effect can be improved.

[0019] S3. Method for promoting dissolution, reducing alkali and inhibiting salt root zone desalination in dry fields:

[0020] Combined with rotary fertilization, according to the degree of soil salinity, liquid fertilizer spreader is used to apply 20-200kg / mu of targeted alkali remover to neutralize the surface OH - , lower soil pH, promote metal ion dissolution, and quickly elute Na through rainwater or irrigation water + ion.

[0021] The present invention has the following beneficial effects: Compared with the current existing research, the present invention is different from the traditional simple solid improvement model. It uses citric acid fermentation broth to produce extract as the main raw material to develop a green, efficient, low-cost, and sustainable liquid water-soluble alkali-reducing agent product, and creates a new model for comprehensive improvement of soda saline-alkali land combining solid and liquid. It can achieve quantitative and precise control according to different crops and different degrees of salinity, making up for the shortcomings of low uniformity and poor targeting of solid improvement. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0023] Figure 1 The effect of using targeted de-alkali agent on moderate saline-alkali soil;

[0024] Figure 2 It is the effect of using targeted de-alkali agent in severely saline-alkali soil. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] Preparation Example 1: Preparation of fermentation broth of citric acid fermented by Aspergillus niger

[0027] Citric acid was added to sterile water at a concentration of 100 g / L, and Aspergillus niger was inoculated. The mixture was fermented at 27° C. and 100 r / min for 36 hours, and the supernatant was collected after centrifugation to obtain a fermentation broth of citric acid fermented by Aspergillus niger.

[0028] Example 1: Method for preparing targeted de-alkali agent for soda saline-alkali land

[0029] (1) The fermentation liquid of citric acid fermented by Aspergillus niger is neutralized with calcium carbonate, the supernatant is filtered, concentrated 30 times, and the supernatant is filtered again to prepare a polysaccharide solution.

[0030] (2) Add 10 parts by weight of amino acid, 5 parts by weight of lactic acid and 7 parts by weight of acetic acid to 100 parts by weight of citric acid fermentation broth obtained by fermenting citric acid with Aspergillus niger to obtain an alkali-eliminating and dissolution-promoting component.

[0031] (3) Add 43 parts by weight of the alkali-eliminating and dissolving-promoting component to 55 parts by weight of the polysaccharide solution, compound the reinforcing replacement component, add 2 parts by weight of calcium citrate according to the calcium content of the calcium salt after mixing, stir until completely dissolved, and obtain a targeted alkali-eliminating agent.

[0032] Product indicators: citric acid (calculated as citric acid monohydrate) ≥15%; amino acid (total of 18 amino acids) ≥3%; total acid (calculated as citric acid monohydrate) ≥20%; polysaccharide (calculated as glucose) ≥1.5%.

[0033] Example 2: Effect of targeted de-alkali agent for soda saline-alkali land on de-alkali of moderate saline-alkali soil

[0034] Moderate soda-type saline-alkali soil was collected, air-dried, crushed and sieved through a 20-mesh sieve for later use. 100.00 g of sieved saline-alkali soil was added to each beaker, followed by 250 ml of deionized water and a targeted de-alkali agent at a dosage of 0.75 t / hectare. The soil was stirred for 1 min and then allowed to stand for 30 min. The pH and conductivity were then tested. Figure 1 As shown in the figure, the original soil pH was 8.71, and the conductivity of the supernatant was 4.810ms / cm. After adding the de-alkali agent, the pH dropped to 6.43 and the conductivity of the supernatant increased to 6.081ms / cm 30 minutes later. As time went by, the pH first increased slowly and then decreased slowly, and finally stabilized. After 48 hours, the soil pH was 7.16; as time went by, the conductivity increased slowly, and after 48 hours, the conductivity of the supernatant was 6.461ms / cm. It can be seen that the use of targeted de-alkali agents on moderately saline-alkali soils can quickly reduce the soil pH value, increase the dissolution of salt ions in the soil, and can achieve rapid alkali reduction and salt removal in combination with rainfall, irrigation and other measures.

[0035] Example 3: Effect of targeted de-alkali agent on de-alkali soil in severe saline-alkali soil

[0036] Severe soda-type saline-alkali soil was collected, air-dried, crushed and sieved through a 20-mesh sieve for later use. 100.00 g of sieved saline-alkali soil was added to each beaker, followed by 250 ml of deionized water and a targeted de-alkali agent at a dosage of 1 ton / hectare. The mixture was stirred for 1 min and then allowed to stand for 30 min. The pH and conductivity were then tested. Figure 2 As shown in the figure, the original soil pH was 9.41, and the conductivity of the supernatant was 6.405ms / cm. After adding the de-alkali agent for 30 minutes, the pH dropped to 8.11, and the conductivity of the supernatant increased to 7.063ms / cm. As time went by, the pH first increased slowly and then decreased slowly, and finally stabilized. After 48 hours, the soil pH was 8.19; as time went by, the conductivity increased slowly, and after 48 hours, the conductivity of the supernatant was 7.782ms / cm. It can be seen that the use of targeted de-alkali on heavy saline-alkali soil can effectively reduce the soil pH value, accelerate the dissolution of salt ions in the soil, and combine rainfall, irrigation and other measures to achieve rapid alkali reduction and salt removal.

[0037] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A targeted de-alkali agent for soda saline-alkali land, characterized in that: The soda saline-alkali land targeted de-alkali agent consists of three functional components: a de-alkali dissolution-promoting component, a strengthening and replacing component, and a flocculation and agglomeration component; the de-alkali dissolution-promoting component includes citric acid and another component, and the other component is selected from at least one of amino acids, lactic acid, and acetic acid; the strengthening and replacing component is selected from at least one of calcium citrate, monocalcium citrate, and dicalcium citrate; the flocculation and agglomeration component is selected from one of chitosan and chitin.

2. The soda saline-alkali land targeted de-alkali agent according to claim 1, characterized in that: The alkali-eliminating and dissolving-promoting component accounts for 20±5% of the total mass of the soda saline-alkali land targeted alkali-eliminating agent on a dry basis, of which citric acid accounts for 70-80%; the pH of the final product is 2.0-4.0, and the acidity is 20±5%.

3. The soda saline-alkali land targeted de-alkali agent according to claim 1, characterized in that: The ratio of the strengthening replacement component to the total mass of the soda saline-alkali land targeted de-alkali agent is 1-5% on a dry basis, and the product after combining with the de-solubility promoting component can finally dissolve Ca 2+ The concentration is greater than 5g / L.

4. The soda saline-alkali land targeted de-alkali agent according to claim 1, characterized in that: The effective component polysaccharide in the flocculation and aggregation component accounts for 2-5% of the total mass of the soda salt-alkali land targeted de-alkali agent.

5. A method for preparing a targeted de-alkali agent for soda saline-alkali land according to any one of claims 1 to 4, characterized in that: The following steps are involved: (1) Flocculation and agglomeration component: the fermentation liquid of citric acid fermented by Aspergillus niger is neutralized with calcium carbonate, the supernatant is filtered, and the supernatant is filtered again after being concentrated 20-40 times; (2) Alkali-eliminating and dissolution-promoting component: citric acid is mixed with another component to obtain a mixed organic acid solution; (3) Evenly mix the flocculation and aggregation component and the alkali removal and dissolution promoting component, add the strengthening replacement component, stir until dissolved, and obtain the soda saline-alkali land targeted alkali removal agent.

6. The preparation method according to claim 5, characterized in that: The flocculation and aggregation component is a polysaccharide solution formed by dissolving Aspergillus niger mycelium.

7. A method for using the soda saline-alkali land targeted de-alkali agent according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1. Targeted de-alkali and de-salt removal in paddy fields: after rotary tillage, combine water harrowing and apply targeted de-alkali agent for saline-alkali land, keep the water layer on the field surface at 10cm, let it stand for 2-3 days, drain the water after confirming the mud has settled, and quickly reduce alkali and de-salt; S2. Methods for reducing alkali and controlling salt in the key period of rice: applying targeted alkali-removing agents for soda saline-alkali land during the rice greening period, tillering period, booting period and grain filling period; S3. Dryland dissolution promotion, alkali reduction and salt suppression root zone desalination method: Combined with rotary soil, liquid fertilizer spreader is used to apply soda saline-alkali land targeted de-alkali agent according to the degree of soil salinity to neutralize the surface OH - , lower soil pH, promote metal ion dissolution, and quickly elute Na through rainwater or irrigation water + ion.

8. The method of use according to claim 7, characterized in that: The application amount of the soda saline-alkali land targeted de-alkali agent in step S1 is 50-100 kg / mu.

9. The method of use according to claim 7, characterized in that: The application amount of the soda saline-alkali land targeted de-alkali agent in step S2 is 10-30 kg / mu.

10. The method of use according to claim 7, characterized in that: The application amount of the soda saline-alkali land targeted de-alkali agent in step S2 is 20-200 kg / mu.

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