Fertilization aid and application thereof in returning liquid manure to field

Abstract

The invention belongs to the technical field of fertilizer assistants, and particularly relates to a fertilization assistant and application thereof in returning liquid manure to the field. The fertilizing aid provided by the invention comprises a first component and a second component, the first component comprises ferric chloride or ferric sulfate, and the second component comprises polyacrylamide. Soluble and non-soluble particles and functional groups in the manure slurry mostly carry negative charges, after ferric chloride or ferric sulfate is added, the bond bridge effect can be achieved, negative charge particles and anions are flocculated into larger particles, the larger particles are separated out from the manure slurry, and then solid-liquid separation of the manure slurry is achieved; the polyacrylamide has a charge flocculation effect, and a solution of the polyacrylamide is colloidal and can also adsorb soluble organic matters in the feces, so that solid-liquid separation of the feces slurry is realized.

Description

Technical Field

[0001] The invention belongs to the technical field of fertilizer adjuvants, and in particular relates to a fertilization adjuvant and application thereof in returning liquid manure to fields. Background Art

[0002] The large amount of manure and sewage produced by centralized animal husbandry will threaten the surrounding environment and also put great environmental pressure on farms and cooperatives. In the Northeast, especially in Heilongjiang, due to climatic reasons, biogas and other technologies are not easy to promote. The main method of manure and sewage disposal is to return fertilizer to the field; the traditional method of returning manure to the field requires the separation of dry and wet manure and sewage first, and then the dry material is composted and used as base fertilizer. The large amount of wastewater generated during this period is stored in oxidation ponds, and after the land hardens in winter, it is returned to the field with agricultural machinery tanks. Liquid full-volume return to the field does not need to be separated, but the manure and urine and wastewater from cleaning the livestock house are collected together, and then open, covered or bladder storage methods are used, and anaerobic fermentation is returned to the field. In contrast, the nutrient utilization of full-volume return to the field is more complete and the absorption is more thorough. In addition, the liquid full-volume return to the field process is simple, which can reduce the amount of chemical fertilizers, promote the mineralization and decomposition of straw and stubble, and increase the content of soil organic matter, which is in line with the weight-loss and efficiency-enhancing production method advocated by the country in recent years. However, returning the liquid manure to the field in full also has the disadvantages of difficult transportation, small coverage area, slow infiltration limiting the single application amount, and uneven application due to downhill flow. Among them, the problems of slow infiltration and downhill flow are mainly due to the viscosity of liquid manure, which is not easy to enter the soil pores. Therefore, certain measures are needed to increase and accelerate the infiltration of liquid manure so that it can be returned to the field in large quantities and avoid uneven fertilization. Summary of the invention

[0003] The purpose of the present invention is to provide a fertilization adjuvant and its application in returning liquid manure to the field, so as to change the physical properties of liquid manure, promote its solid-liquid separation in the field, accelerate the infiltration of the liquid part into the deep soil, and realize large-scale and uniform fertilization.

[0004] The present invention provides the application of a fertilization adjuvant in returning liquid manure to fields;

[0005] The fertilization adjuvant comprises a first component and / or a second component, wherein the first component comprises ferric chloride and / or ferric sulfate, and the second component comprises polyacrylamide.

[0006] Preferably, the concentration of the first component in the fertilization adjuvant is 0.01 to 1 M; the concentration of the second component is 0.01 to 10 wt.%.

[0007] Preferably, the polyacrylamide is cationic polyacrylamide.

[0008] Preferably, the returning of liquid manure to the field includes one or more of improving the solid-liquid separation efficiency of liquid manure, improving the infiltration efficiency of liquid manure and increasing the amount of dry matter returned to the field of liquid manure.

[0009] Preferably, the dry matter of the liquid manure is <12 wt.%.

[0010] Preferably, the liquid manure comprises 0.34-0.37 wt.% N, 0.20-0.23 wt.% P2O5, 0.24-0.26 wt.% K2O, 2.91-3.03 wt.% organic matter and 0.38-0.47 wt.% water-insoluble matter.

[0011] The present invention also provides a method for returning liquid manure to fields, comprising the following steps:

[0012] Add fertilizer aids to liquid manure and mix well;

[0013] The fertilization adjuvant comprises a first component and / or a second component, wherein the first component comprises ferric chloride and / or ferric sulfate, and the second component comprises polyacrylamide.

[0014] Preferably, the concentration of the first component in the fertilization adjuvant is 0.01 to 1 M; the concentration of the second component is 0.01 to 10 wt.%;

[0015] The volume ratio of the fertilization adjuvant to the liquid manure is 1:2-10000.

[0016] Preferably, the mixing method is stirring for 3 to 5 minutes.

[0017] The present invention also provides a fertilization adjuvant for returning liquid manure to fields, the fertilization adjuvant comprises a first component and / or a second component, the first component comprises ferric chloride and / or ferric sulfate, and the second component comprises polyacrylamide;

[0018] The concentration of the first component in the fertilization adjuvant is 0.01-1M; the concentration of the second component is 0.01-10wt.%.

[0019] Beneficial Effects

[0020] The present invention provides the application of a fertilization adjuvant in returning liquid manure to the field; the fertilization adjuvant includes a first component and / or a second component, the first component includes ferric chloride and / or ferric sulfate, and the second component includes polyacrylamide; the soluble and insoluble particles and functional groups in the liquid manure are mostly negatively charged, and after adding ferric chloride or ferric sulfate, it can play a bond bridge role, flocculate anions into larger particles, precipitate from the manure slurry, and then separate the manure slurry from solid and liquid; polyacrylamide has a flocculation effect of bridging anions, and its solution itself is colloidal and can also adsorb soluble organic matter in manure, so that the manure slurry is separated from solid and liquid. The present invention changes the physical properties of liquid manure by adding a fertilization adjuvant, promotes its solid-liquid separation in the field, accelerates the infiltration of the liquid part into the deep soil, and realizes large-scale and uniform fertilization. In addition, the infiltration enhancer adds microbial agents, so that its organic nutrients can be accelerated to mineralize and decompose into effective mineral nutrients, promote plant absorption and utilization, and achieve multiple effects of fertilization, land conservation and increased production. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] 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.

[0022] Figure 1 The results of the flocculation observation experiment of the liquid cow dung slurry in Example 1;

[0023] Figure 2 The test tube in Example 2 was allowed to stand for 3 minutes after being filled to volume;

[0024] Figure 3 The test tube in Example 2 was set to volume and then left to stand for 30 minutes.

[0025] Figure 4 The alum flowers are formed by mixing and stirring the ferric chloride solution, cationic polyacrylamide and feces slurry stock solution in Example 3;

[0026] Figure 5 This is the concentrated flocculated slurry obtained in Example 3. DETAILED DESCRIPTION

[0027] The present invention provides application of a fertilization adjuvant in returning liquid manure to fields; the fertilization adjuvant comprises a first component and / or a second component, the first component comprises ferric chloride and / or ferric sulfate, and the second component comprises polyacrylamide.

[0028] In the present invention, the fertilization adjuvant preferably comprises a first component and a second component. The concentration ratio of the first component to the second component in the fertilization adjuvant of the present invention is preferably 0.4M:0.12wt.%.

[0029] In the present invention, the first component includes ferric chloride and / or ferric sulfate, preferably ferric sulfate or ferric chloride. The concentration of the first component in the fertilization adjuvant of the present invention is preferably 0.01 to 1 M, and more preferably 0.02 to 0.2 M. The present invention uses ferric chloride or ferric sulfate as the first component of the fertilization adjuvant, and the trivalent iron ions therein can flocculate organic matter in the manure slurry with electric charge. The electric charge effect can promote the rapid formation of light flocculants, which is beneficial to achieve solid-liquid separation of liquid manure and promote its rapid infiltration in the soil.

[0030] In the present invention, the second component includes polyacrylamide, preferably cationic polyacrylamide; the concentration of the second component is preferably 0.01-10wt.%, more preferably 0.05-0.4wt.%, more preferably 0.1-0.3wt.%, and most preferably 0.2wt.%. The present invention uses polyacrylamide as the second component of the fertilization adjuvant, which has a flocculation effect of solid-liquid separation, and can also amplify the flocculation effect, further promoting the solid-liquid separation of liquid manure.

[0031] The present invention has no strict requirements on the sources of the first component and the second component, and they can be purchased conventionally.

[0032] In the present invention, the returning of liquid manure to the field includes preferably improving the solid-liquid separation efficiency of liquid manure, improving the infiltration efficiency of liquid manure and increasing the amount of dry matter returned to the field of liquid manure or one or more thereof, and further preferably improving the solid-liquid separation efficiency of liquid manure, improving the infiltration efficiency of liquid manure and increasing the amount of dry matter returned to the field of liquid manure.

[0033] In the present invention, the dry matter of the liquid manure is preferably <12wt.%; the liquid manure preferably also includes N0.34-0.37wt.%, P2O50.20-0.23wt.%, K2O 0.24-0.26wt.%, organic matter 2.91-3.03wt.% and water-insoluble matter 0.38-0.47wt.%; further preferably includes N 0.34wt.%, P2O50.23wt.%, K2O0.26wt.%, organic matter 2.91wt.% and water-insoluble matter 0.38wt.%, or further preferably includes N 0.37wt.%, P2O50.20wt.%, K2O 0.24wt.%, organic matter 3.03wt.% and water-insoluble matter content 0.47wt.%.

[0034] The present invention also provides a method for returning liquid manure to fields, comprising the following steps:

[0035] Add fertilizer aids to liquid manure and mix well;

[0036] The fertilization adjuvant comprises a first component and / or a second component, wherein the first component comprises ferric chloride and / or ferric sulfate, and the second component comprises polyacrylamide.

[0037] In the present invention, the concentration of the first component in the fertilization adjuvant is preferably 0.01-1M, more preferably 0.02-0.2M; the concentration of the second component in the fertilization adjuvant is preferably 0.01-10wt.%, more preferably 0.05-0.4wt.%, more preferably 0.1-0.3wt.%, and most preferably 0.2wt.%. The fertilization adjuvant of the present invention preferably includes the first component and the second component, and the concentration ratio of the first component to the second component is preferably 0.4M:0.12wt.%.

[0038] In the present invention, the volume ratio of the fertilization aid to the liquid manure is preferably 1:2 to 10000, more preferably 1:5 to 4000, more preferably 1:10 to 1000, and most preferably 1:40 to 400. When the fertilization aid has and only has the first component or the second component, the volume ratio of the fertilization aid to the liquid manure is preferably 1:2 to 5; when the fertilization aid is the first component and the second component, the volume ratio of the fertilization aid to the liquid manure is preferably 1:40.

[0039] The mixing method of the present invention is preferably stirring, and the mixing time is preferably 3 to 5 minutes, and more preferably 4 minutes.

[0040] In order to further illustrate the present invention, a fertilization adjuvant provided by the present invention and its application in returning liquid manure to fields are described in detail below in conjunction with the accompanying drawings and embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0041] Example 1

[0042] (1) Slurry flocculation observation experiment

[0043] Liquid cow dung slurry provided by Harbin Danqing Agricultural Science and Technology Co., Ltd. was used as the experimental material; wherein, the liquid cow dung slurry was taken from cattle dung that had been subjected to anaerobic fermentation in capsules for more than 3 months and was harmlessly treated; the raw material for capsule fermentation was a mixture of feces and urine in the cowshed of a breeding farm, which was injected into the giant capsule through a pipeline; the composition of the liquid cow dung slurry was as follows: N 0.34wt.%, P2O5 0.23wt.%, K2O 0.26wt.%, organic matter 2.91wt.%, water-insoluble matter content 0.38wt.%, and dry matter <12wt.%.

[0044] The liquid cow dung slurry was divided into three treatment groups, A, B and C. To make the plane observation effect clear, it was diluted with distilled water. The specific treatment was as follows:

[0045] Treatment group A: 2 mL of liquid cow dung slurry was added to a 10 cm culture dish, diluted 5 times with distilled water, and shaken in a circular motion on a water table for 60 s;

[0046] Treatment group B: 2 mL of liquid cow dung slurry was added to a 10 cm culture dish, diluted 5 times with distilled water, and then 2 mL of 1 mol / L ferric chloride solution was added. The solution was shaken in a circular motion on a water table for 60 s to mix the liquid evenly.

[0047] Treatment group C: 2 mL of liquid cow dung slurry was added to a 10 cm culture dish, diluted 5 times with distilled water, and then 5 mL of 2 g / L cationic polyacrylamide solution was added. The mixture was shaken in a circular motion on a water table for 60 s to mix the liquid evenly.

[0048] The three treatment groups were repeated three times and observed after the treatment. The results showed that the cow dung slurry in the culture dish of treatment group A was a relatively uniform mixture ( Figure 1 A), after adding ferric chloride to the cow dung slurry in the culture dish of the B treatment group, there are obvious large flocs floating on the surface, and the liquid part is relatively clear ( Figure 1 B); After the cationic polyacrylamide solution was added to the cow dung slurry in the culture dish of the C treatment group, many small flocs were formed inside the liquid, and the liquid part was slightly turbid compared with B ( Figure 1 C). It can be seen that both multivalent cations and cationic polyacrylamide have flocculation effects for solid-liquid separation.

[0049] (2) Repeat the experiment

[0050] Different batches of liquid cow dung slurry were taken, with the following composition: N 0.37wt.%, P2O5 0.20wt.%, K2O 0.24wt.%, organic matter 3.03wt.%, and water-insoluble matter content 0.47wt.%, dry matter <12wt.%, and flocculation observation experiments were carried out in the same manner as step (1). The results were similar to the above phenomenon. Treatment B formed larger floating flocs, and treatment C also formed small flocs inside the solution, indicating good reproducibility.

[0051] Example 2

[0052] Test tube experiment of ferric chloride and polyacrylamide mixed additives

[0053] Liquid cow dung slurry provided by Harbin Danqing Agricultural Science and Technology Co., Ltd. was used as the experimental material; wherein, the liquid cow dung slurry was taken from cattle dung that had been subjected to anaerobic fermentation in capsules for more than 3 months and was harmlessly treated; the raw material for capsule fermentation was a mixture of feces and urine in the cowshed of a breeding farm, which was injected into the giant capsule through a pipeline; the composition of the liquid cow dung slurry was as follows: N 0.34wt.%, P2O5 0.23wt.%, K2O 0.26wt.%, organic matter 2.91wt.%, water-insoluble matter content 0.38wt.%, and dry matter <12wt.%.

[0054] The liquid cow dung slurry was randomly divided into four treatment groups, A, B, C and D, with three parallels in each treatment group. In order to clearly observe the state of floccules at different depths, distilled water was also used for dilution. In order to observe the change of solid-liquid separation effect over time, two schemes of 3min and 30min were set. The specific treatment was carried out as follows:

[0055] Treatment group A: Take 10 mL of liquid cow dung slurry and add it into a 50 mL test tube, add distilled water, and shake to 50 mL;

[0056] Treatment group B: 10 mL of liquid cow dung slurry was added to a 50 mL test tube, 1 mL of 1 mol / L ferric chloride solution was added, and then the remaining amount of distilled water was added, and the volume was adjusted to 50 mL after being shaken well.

[0057] Treatment group C: Take 10 mL of liquid cow dung slurry and add it to a 50 mL test tube. Add 1 mL of 2 g / L cationic polyacrylamide solution, then add the remaining amount of distilled water, shake well and make up to 50 mL.

[0058] Treatment group D: Take 10 mL of liquid cow dung slurry and add it into a 50 mL test tube. Then add 0.4 mL of 1 mol / L ferric chloride solution and 0.6 mL of 2 g / L cationic polyacrylamide solution. Then add the remaining amount of distilled water and shake to make up to 50 mL.

[0059] In the first solution, the volume was fixed for 3 minutes and then observed. The results were as follows: Figure 2 As shown in the figure, in the test tubes of treatment groups B and D, the flocs float on the top layer of the solution. Since both treatment groups B and D contain ferric chloride, it means that the trivalent iron ions flocculate the organic matter in the fecal slurry with electric charge, and the electric charge can quickly encapsulate the gas formed during the reaction and oscillation, thereby forming lighter floating flocs, leaving the separated liquid at the bottom, which is conducive to the rapid infiltration of the liquid part in the soil.

[0060] In the second solution, the volume was fixed for 30 minutes and then observed. The results were as follows: Figure 3As shown in the figure, the color of the fecal slurry in the test tubes of the C and D treatment groups became significantly lighter, and flocculation and sedimentation appeared at the bottom. The flocculation and sedimentation at the bottom of the test tube of the D treatment group was much higher than that of the C treatment group. This is because the polyacrylamide and ferric chloride in the test tube of the D treatment group amplified the flocculation effect and increased the density of the flocculants, causing them to sink to the bottom. This shows that the flocculation of polyacrylamide is slightly slower than that of multivalent cations, but it can amplify the flocculation effect.

[0061] Three replicates of both protocols showed good reproducibility.

[0062] Example 3

[0063] Flocculation infiltration experiment

[0064] Two treatments were set up, namely treatment 1 and treatment 2, each with three repetitions.

[0065] Treatment 1: Stir 45L of manure slurry in a 50L barrel for 3 minutes, let it stand for 20 minutes and then apply directly.

[0066] Treatment 2: Add 0.25L of ferric chloride solution (1mol / L) and 1L of cationic polyacrylamide (2g / L) to 45L of manure slurry in a 50L barrel, stir for 3min, and then let it stand for 20min to allow the manure slurry to form alum flowers and fully flocculate ( Figure 4 ). Stir well again and apply.

[0067] The experimental site was black soil with no slope. Six ridges were allocated to three replicates of two treatments. Each ridge was 7 meters long, and a 10 cm deep groove was left in the middle of the ridge for applying manure slurry ( Figure 5 ). 16L of mixed manure slurry was applied to each ridge in treatment 1 or treatment 2, and the timing was started after the manure slurry was applied to each ridge. The results showed that the infiltration time of the three replicates of treatment 1 was more than 2h, while the liquid part of treatment 2 had basically completed infiltration within 3-7min, and the flocculated dry matter remained on the soil surface.

[0068] It can be seen from the above that the fertilization adjuvant provided by the present invention uses a small amount of multivalent cations as a guide to quickly separate solid and liquid, and uses cationic polyacrylamide as the main adjuvant to expand the flocculation effect. A good solid-liquid separation effect can make the liquid part infiltrate, and the flocculants remain in situ on the surface, avoiding the flow down the slope due to non-infiltration. In addition, the combined use of this adjuvant has potential benefits. On the one hand, it reduces the input of inorganic salts into the soil. On the other hand, multivalent cations and high molecular polymers can promote the close combination of organic matter and soil mineral colloids, and promote the formation of soil organic-inorganic complexes (soil aggregates), thereby improving soil physical properties.

[0069] 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. Application of fertilizer adjuvants in returning liquid manure to fields; The fertilization adjuvant comprises a first component and / or a second component, wherein the first component comprises ferric chloride and / or ferric sulfate, and the second component comprises polyacrylamide.

2. The use according to claim 1, characterized in that: The concentration of the first component in the fertilization adjuvant is 0.01-1M; the concentration of the second component is 0.01-10wt.%.

3. The use according to claim 1, characterized in that: The polyacrylamide is cationic polyacrylamide.

4. The use according to claim 1, characterized in that: The returning of liquid manure to the field includes one or more of improving the solid-liquid separation efficiency of the liquid manure, improving the infiltration efficiency of the liquid manure, and increasing the amount of dry matter returned to the field of the liquid manure.

5. The use according to any one of claims 1 to 4, characterized in that: The dry matter of the liquid manure is <12 wt.%.

6. The use according to claim 5, characterized in that: The liquid manure comprises 0.34-0.37 wt. % of N, 0.20-0.23 wt. % of P2O5, 0.24-0.26 wt. % of K2O, 2.91-3.03 wt. % of organic matter and 0.38-0.47 wt. % of water-insoluble matter.

7. A method for returning liquid manure to fields, characterized in that: The following steps are involved: Add fertilizer aids to liquid manure and mix well; The fertilization adjuvant comprises a first component and / or a second component, wherein the first component comprises ferric chloride and / or ferric sulfate, and the second component comprises polyacrylamide.

8. The method according to claim 7, characterized in that The concentration of the first component in the fertilization adjuvant is 0.01 to 1 M; the concentration of the second component is 0.01 to 10 wt.%; The volume ratio of the fertilization adjuvant to the liquid manure is 1:2-10000.

9. The method according to claim 7 or 8, characterized in that: The mixing method is stirring, and the time is 3 to 5 minutes.

10. A fertilization adjuvant for returning liquid manure to fields, characterized in that: The fertilization adjuvant comprises a first component and / or a second component, wherein the first component comprises ferric chloride and / or ferric sulfate, and the second component comprises polyacrylamide; The concentration of the first component in the fertilization adjuvant is 0.01-1M; the concentration of the second component is 0.01-10wt.%.

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