CN113149753A - Low-heavy-metal biogas residue composite organic silicon fertilizer with slow release function and preparation method thereof - Google Patents

Low-heavy-metal biogas residue composite organic silicon fertilizer with slow release function and preparation method thereof Download PDF

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CN113149753A
CN113149753A CN202110307152.6A CN202110307152A CN113149753A CN 113149753 A CN113149753 A CN 113149753A CN 202110307152 A CN202110307152 A CN 202110307152A CN 113149753 A CN113149753 A CN 113149753A
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silicon
biogas residue
preparation
heavy metal
fertilizer
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王晓燕
王红
包亚莉
张永锋
张印民
梁浩东
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Inner Mongolia University of Technology
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Inner Mongolia University of Technology
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    • C—CHEMISTRY; METALLURGY
    • C05—FERTILISERS; MANUFACTURE THEREOF
    • C05D—INORGANIC FERTILISERS NOT COVERED BY SUBCLASSES C05B, C05C; FERTILISERS PRODUCING CARBON DIOXIDE
    • C05D3/00—Calcareous fertilisers
    • C05D3/02—Calcareous fertilisers from limestone, calcium carbonate, calcium hydrate, slaked lime, calcium oxide, waste calcium products
    • C—CHEMISTRY; METALLURGY
    • C05—FERTILISERS; MANUFACTURE THEREOF
    • C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
    • C05G3/00—Mixtures of one or more fertilisers with additives not having a specially fertilising activity
    • C—CHEMISTRY; METALLURGY
    • C05—FERTILISERS; MANUFACTURE THEREOF
    • C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
    • C05G3/00—Mixtures of one or more fertilisers with additives not having a specially fertilising activity
    • C05G3/40—Mixtures of one or more fertilisers with additives not having a specially fertilising activity for affecting fertiliser dosage or release rate; for affecting solubility
    • C—CHEMISTRY; METALLURGY
    • C05—FERTILISERS; MANUFACTURE THEREOF
    • C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
    • C05G3/00—Mixtures of one or more fertilisers with additives not having a specially fertilising activity
    • C05G3/80—Soil conditioners
    • C—CHEMISTRY; METALLURGY
    • C05—FERTILISERS; MANUFACTURE THEREOF
    • C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
    • C05G5/00—Fertilisers characterised by their form
    • C05G5/10—Solid or semi-solid fertilisers, e.g. powders
    • C05G5/12—Granules or flakes

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  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Organic Chemistry (AREA)
  • Pest Control & Pesticides (AREA)
  • Soil Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Inorganic Chemistry (AREA)
  • Fertilizers (AREA)

Abstract

The invention discloses a low heavy metal biogas residue composite organic silicon fertilizer with a slow release function and a preparation method thereof, wherein the method comprises the following steps: firstly, separating the pretreated biogas residue to obtain upper liquid and residual substrate; (II) dehydrating, drying and grinding the residual substrate to prepare substrate powder; and (III) granulating the substrate powder to prepare the finished product of the low-heavy metal biogas residue composite silicon fertilizer. And the low heavy metal biogas residue composite organic silicon fertilizer with the slow release function prepared by the method. The invention has the advantages of simple preparation method, low raw material cost, comprehensive nutrients, high effective silicon content and low content of migratable heavy metals.

Description

Low-heavy-metal biogas residue composite organic silicon fertilizer with slow release function and preparation method thereof
The technical field is as follows:
the invention relates to a composite silicon fertilizer and a preparation method thereof, in particular to a low heavy metal biogas residue composite organic silicon fertilizer with a slow release function and a preparation method thereof.
Background art:
with the improvement of the large-scale degree of the livestock and poultry breeding industry, the pressure of the breeding waste discharged in large quantity on the surrounding environment such as water, soil, atmosphere and the like is continuously increased, and great adverse effects and potential environmental hazards are brought. The biogas engineering is one of the most widely applied solutions in the resource utilization of livestock and poultry breeding wastes in various countries at present. However, in the biogas engineering, besides biogas production, a huge amount of biogas residues with high water content can be generated, wherein the biogas residues are rich in a large amount of nutrient substances such as nitrogen, phosphorus, potassium, humic acid and the like, and organic fertilizers can be produced after effective treatment.
Because heavy metals such as copper, cadmium, zinc, arsenic and the like are inevitably brought in the livestock and poultry breeding process, the heavy metals are difficult to be utilized by the livestock and poultry and brought into excrement, and finally enter biogas residues, if the heavy metals are directly used as biogas manure without being processed for application, the heavy metals are accumulated in soil and absorbed by crops, and finally enter human bodies through the food chain accumulation effect, thereby bringing great harm to human health and environment. Therefore, before the biogas residues are used for producing biogas manure, heavy metal toxicity must be removed firstly.
The heavy metals in the biogas manure are strictly limited and regulated in various countries, and in the national standard (solicitation draft) of agricultural biogas manure newly compiled in China, harmful heavy metals such as arsenic, cadmium, chromium, lead, mercury and the like in the biogas manure are classified and limited according to application objects, wherein the limit of the heavy metals in the biogas manure for edible crops is greatly reduced and is very strict compared with the current standard. Of particular note are: although the apparent content of heavy metals in the residue after anaerobic digestion is not high, the nutrient substances are highly concentrated in the biogas fertilizer production, so that the concentration of the heavy metals in the residue is greatly increased. More particularly, the heavy metal has biotoxicity, nondegradable property and accumulation property, and can be accumulated in soil by long-term application of the heavy metal-containing biogas manure. Therefore, the heavy metal toxicity problem is one of the key problems which must be solved in the biogas residue biogas fertilization utilization, but the heavy metal toxicity problem in the biogas residue in the prior art is not paid enough attention and an effective control method is not adopted.
The chemical forms of heavy metals can be divided into two major categories, namely, dissolved heavy metals and granular heavy metals which are easy to be converted into dissolved heavy metals and have biotoxicity and mobility. Therefore, the fixation and conversion of the dissolved heavy metals in the biogas residues are the key for reducing the content of the heavy metals in the biogas fertilizer.
Although the total silicon content in the soil can reach about 30%, 99% of the total silicon content exists in a crystalline state or an amorphous state, mainly exists in a quartz or clay mineral form, and cannot be absorbed by plants. The effective silicon in the soil is silicon which can be absorbed and utilized by crops in the current season, and also comprises monosilicic acid in soil solution and various components which are easy to be converted into the monosilicic acid, such as polysilicic acid, exchange state silicon, a part of colloid state silicon and the like, and a dynamic equilibrium conversion mode exists in the soil solution. In fact, the monosilicic acid silicon which can be directly absorbed and utilized by crops is not much in soil. Because monosilicic acid silicon is the main existing form of water-soluble silicon dissolved in soil solution, but the amorphous silicon in the soil is much less than the crystalline silicon, the water-soluble silicon is much less, and in addition, with the rapid development of agriculture in recent years, crops continuously have high yield, and the absorption of effective silicon in the soil by the crops is further accelerated, the existing effective silicon in the soil is used for providing the silicon nutrition required by the crops, so that the modern agricultural production cannot be met seriously.
The silicon fertilizer is in a mineral form, mainly consists of amorphous state, has no definite molecular formula and mainly represents CaSiO3、Ca2SiO4、Mg2SiO4、Ca3Mg(SiO4)2And the like. The silicon fertilizer is a good quality fertilizer, a health-care fertilizer and a plant regulating fertilizer, and is a novel multifunctional fertilizer which is incomparable with other chemical fertilizers. The silicon fertilizer can be used as a fertilizer for providing nutrients, can be used as a soil conditioner for improving soil, and has the functions of preventing diseases, preventing insects and reducing toxicity. The silicon fertilizer has the outstanding advantages of no toxicity, no smell, no deterioration, no loss, no public nuisance and the like, and becomes green for developmentHigh-efficiency and high-quality fertilizer for ecological agriculture. However, the silicon fertilizer is used as a fertilizer alone, has single nutrient and cannot provide N, P and organic matters needed by crops.
The invention content is as follows:
in order to solve the technical problems, the invention aims to provide the low heavy metal biogas residue composite organic silicon fertilizer with the advantages of simple preparation method, low raw material cost, comprehensive nutrients, high effective silicon content, low migratable heavy metal content and slow release function and the preparation method thereof.
The invention provides a preparation method of a low heavy metal biogas residue composite organic silicon fertilizer with a slow release function, which comprises the following steps:
firstly, separating the pretreated biogas residue to obtain upper liquid and residual substrate: mixing 100-800 kg of calcium-magnesium-silicon functional material with hierarchical pore distribution with 1-8 tons of biogas residues, stirring for 15-100 min, standing for 15-50 min, separating the upper layer liquid, and taking the residual substrate as a mixture of the residual calcium-magnesium-silicon functional material and biogas residues; wherein the biogas residue is obtained by co-digesting a plurality of substrates such as livestock and poultry manure, straws and the like.
(II) dehydrating, drying and grinding the residual substrate to prepare substrate powder;
and (III) granulating the substrate powder to prepare the finished product of the low-heavy metal biogas residue composite silicon fertilizer.
Further, the calcium, magnesium and silicon functional material with the hierarchical pore distribution is prepared by the following method:
(1) preparation of NaO. xSiO by alkali dissolution reaction2Solution: mixing the silicon-rich solid waste, sodium hydroxide and water to perform alkali dissolution reaction to obtain NaO xSiO2A solution;
(2) hydrothermal reaction for preparing xCaO yMgO zSiO2Suspension: in the NaO. xSiO2Adding lime suspension and MgO suspension into the solution, mixing, and performing hydrothermal reaction to obtain xCaO.yMgO.z SiO2A suspension;
(3) and (3) carrying out suction filtration, washing and drying to obtain the calcium-magnesium-silicon functional material: the xCaO yMgO zSiO2The suspension is filtered, washed and dried to obtain the calcium-magnesium-silicon functional material with multi-level pore distributionAnd (5) feeding.
Further, in the step (1), the mass ratio of the silicon-rich solid waste to the sodium hydroxide is 1: 0.5-1: 1.5; the mass ratio of the total solid to the water is 1: 5-1: 10.
Further, SiO in the silicon-rich solid waste2The content is 35-70 wt%.
Further, the silicon-rich solid waste is any one or a combination of more of fly ash, micro silicon powder, coal gangue and diatomite.
Further, in the step (2), the lime suspension and the NaO. xSiO2Mixing the solutions according to the molar ratio of Ca to Si of 0.5-2.0; the MgO suspension and the NaO xSiO2Mixing the solution according to the Mg/Si molar ratio of 0.5-2.0; the solid-liquid ratio is 1: 20-1: 40.
Further, in the step (1), the alkali dissolution reaction temperature is 90-120 ℃, and the reaction time is 3-6 h.
Further, in the step (2), the hydrothermal reaction temperature is 150-190 ℃, and the reaction time is 4-7 h.
Although MgSiO is not present in FIG. 43Characteristic peaks, but FIG. 3-b has demonstrated the presence of Mg in the material, indicating Mg2+Introducing CaO-SiO2-H2O system, replacing part of the interlayer Ca2+Forming a solid solution. Mg (magnesium)2+Is added so that CaO-SiO2-H2Si-O chains in an O system form a short chain structure, so that amorphous bodies are easier to form and crystallization is not easy to form (amorphous silicon and magnesium are effective silicon and magnesium in the fertilizer). Wherein the ratio Mg/Ca determines the degree of crystallisation of the material, the Mg/Ca ratio forming a solid solution within the range of the invention, Mg in excess of this ratio producing Mg (OH)2And (4) precipitating. In addition, the addition amount of Mg directly determines the pore distribution characteristics of the material and determines whether a multimodal pore size distribution structure beneficial to full solid-liquid contact can be formed.
On the other hand, the invention provides the low heavy metal biogas residue composite organic silicon fertilizer with the slow release function, which is prepared by the preparation method of the low heavy metal biogas residue composite organic silicon fertilizer with the slow release function.
Numerous studies have demonstrated that the heavy metal forms can be classified into: exchangeable state, carbonate combined state, iron-manganese oxide state, organic combined state and residue state. Wherein, the exchangeable state and the carbonate combined state are forms which are easily absorbed by crops; the iron-manganese oxide state, the organic combination state and the residue state, particularly the heavy metal in the residue state are not easy to be absorbed by crops. According to the invention, the calcium-magnesium-silicon functional material with multi-level pore distribution is used as the solid-liquid separation pretreatment agent for cultivating the anaerobic digestion residues of the excrement, namely the biogas residues, so that the action principle of reducing heavy metal pollution is not to remove heavy metals, but to convert exchangeable and carbonate-bound heavy metals in the environment into residue heavy metals, thereby reducing the migration of the heavy metals and enabling the heavy metals to have no biotoxicity any more.
The silicon fertilizer mainly comprises two categories of citrate soluble silicon fertilizer and water soluble silicon fertilizer, wherein the citrate soluble silicon fertilizer is the silicon fertilizer which is insoluble in water and can be absorbed by plants after being dissolved in acid.
The invention has the advantages that:
(1) the calcium-magnesium-silicon functional material with hierarchical pore distribution is synthesized by taking silicon-rich solid wastes such as fly ash and the like as raw materials, mainly comprises Ca, Si, Mg, O and H, is all available elements of fertilizers, and can be independently used as calcium-magnesium-silicon fertilizers; and the raw materials have wide sources, low price, low production cost and environmental protection.
(2) The calcium, magnesium and silicon functional material with multilevel pore distribution used in the invention is amorphous and has multilevel pore distribution; the aperture is concentrated in three areas, which are: 2-10 nm; 10-30 nm; 30-300 nm trimodal distribution; the specific surface area is 150-300 m2(ii)/g; the total pore volume is 0.432-0.819 cm3(ii)/g; rich and developed pores, large specific surface area, rich surface charge, high cation exchange capacity and high adsorption capacity.
(3) The invention uses the calcium-magnesium-silicon functional material with multi-level pore distribution as the solid-liquid separation pretreatment agent for cultivating the anaerobic digestion residues of the feces, namely the biogas residues, and by utilizing the ion exchange characteristic of the material, a small amount of soluble heavy metal ions in the biogas residues can be fixed in crystal lattices to form stable substances, so that the heavy metal ions are prevented from migrating, and the heavy metal loses the biotoxicity.
(4) Meanwhile, the calcium-magnesium-silicon functional material with the multilevel pore distribution has a large amount of Ca2+And hydroxyl is combined with soluble P in the biogas residues to form Ca-P precipitates, and P elements are concentrated into biogas residues from biogas slurry, so that the content of P in the biogas residue fertilizer is greatly increased. Due to the large adsorption capacity, a large amount of nitrogen elements in the biogas residues can be adsorbed, the adsorption ratio is more than 10g/mL, and the content of N in the biogas residue fertilizer is greatly improved. Therefore, on the basis of the calcium-magnesium-silicon functional material with hierarchical pore distribution, elements such as humus, N, P, K and the like in the biogas residue are further compounded, so that the nutrients of the silicon-based functional material are more comprehensive, and meanwhile, the humus and the calcium-magnesium-silicon fertilizer are jointly used, so that the effective silicon content in the calcium-magnesium fertilizer is greatly increased.
(5) The calcium, magnesium and silicon functional material with the multilevel pore distribution has abundant charge distribution on the surface, and can neutralize colloid charge in the biogas residue liquid, thereby greatly reducing the viscosity of anaerobic digestion liquid and greatly reducing the subsequent separation load.
Description of the drawings:
FIG. 1 is a pore size distribution diagram of a Ca-Mg-Si functional material prepared in example 1;
FIG. 2 is an SEM image of the Ca-Mg-Si functional material prepared in example 1;
FIG. 3 is TEM and EDS images of Ca-Mg-Si functional material prepared in example 1;
FIG. 4 is an XRD pattern of the Ca, Mg and Si functional material prepared in example 1;
FIG. 5 is an SEM image of materials prepared in comparative examples 1-5.
FIG. 6 is a comparison of the growth of pakchoi with different fertilizers applied for the same time.
The specific implementation mode is as follows:
example 1: the preparation method of the low heavy metal biogas residue composite organic silicon fertilizer with the slow release function comprises the following steps:
firstly, separating the pretreated biogas residue to obtain upper liquid and residual substrate: mixing 500kg of calcium, magnesium and silicon functional materials with hierarchical pore distribution with 4 tons of biogas residues, stirring for 50min, standing for 30min, and separating upper-layer liquid, wherein the residual substrate is a mixture of the residual calcium, magnesium and silicon functional materials and biogas residues; wherein the biogas residue is obtained by co-digesting a plurality of substrates such as livestock and poultry manure, straws and the like.
(II) dehydrating, drying and grinding the residual substrate to prepare substrate powder; in the embodiment, the residual substrate is put into a screw extruder to remove excessive water, and then is dried in a dryer for 12 hours, and the dried mixture is ground and then is sieved by a 60-mesh sieve to obtain substrate powder.
And (III) granulating the substrate powder to prepare the finished product of the low-heavy metal biogas residue composite silicon fertilizer. In this example, the substrate powder and the polyvinyl alcohol solution were mixed and pelletized in a pelletizer, in which polyvinyl alcohol is a binder. The mixture ratio of the substrate powder and the polyvinyl alcohol is 2.5kg/L, and the mass concentration of the polyvinyl alcohol solution is 10%. And drying the granulated granular composite organic silicon fertilizer in a dryer for 1h to obtain the low heavy metal biogas residue composite organic silicon fertilizer with the slow release function.
In this embodiment, the calcium, magnesium, and silicon functional material with hierarchical pore distribution is prepared as follows:
(1) preparation of NaO. xSiO by alkali dissolution reaction2Solution: mixing the silicon-rich solid waste, sodium hydroxide and water to perform alkali dissolution reaction to obtain NaO xSiO2A solution;
in the embodiment, the alkali dissolution reaction temperature is 110 ℃, and the reaction time is 4 hours; the silicon-rich solid waste is fly ash; SiO in silicon-rich solid waste2The content is 40 wt%; the mass ratio of the silicon-rich solid waste to the sodium hydroxide is 1: 1; the mass ratio of total solids to water was 1: 8.
(2) Hydrothermal reaction for preparing xCaO yMgO zSiO2Suspension: in NaO. xSiO2Adding lime suspension and MgO suspension into the solution, mixing, and performing hydrothermal reaction to obtain xCaO.yMgO.z SiO2A suspension;
in this example, the hydrothermal reaction temperature was 160 ℃ and the reaction time was 5 hours. Lime suspension and NaO. xSiO2Mixing the solution according to the molar ratio of Ca to Si of 1.2; MgO suspension and NaO xSiO2Mixing the solution according to the Mg/Si molar ratio of 0.8; the solid-liquid ratio is 1: 30.
(3) And (3) carrying out suction filtration, washing and drying to obtain the calcium-magnesium-silicon functional material: xCaO yMgO zSiO2And (4) carrying out suction filtration, washing and drying on the suspension to obtain the calcium-magnesium-silicon functional material.
In the embodiment, the calcium, magnesium and silicon functional material is obtained after repeated washing three times, suction filtration and drying.
The calcium, magnesium and silicon functional material with hierarchical pore distribution prepared in this example has the components of Ca, Si, Mg, O and H, all being fertilizer available elements, as shown in fig. 3-b and table 1.
The calcium-magnesium-silicon functional material with hierarchical pore distribution prepared in this example is amorphous, has hierarchical pore distribution, and as shown in fig. 1, the pore diameter is concentrated in three regions, which are: 2-10 nm; 10-30 nm; 30-300 nm trimodal distribution.
The calcium-magnesium-silicon functional material with hierarchical pore distribution prepared by the embodiment has rich and developed pores as shown in fig. 2. Specific surface area 267m2(ii)/g; total pore volume 0.762cm3(ii)/g; large specific surface area, rich surface charge, high cation exchange capacity and high adsorption capacity.
Example 2: the preparation method of the low heavy metal biogas residue composite organic silicon fertilizer with the slow release function comprises the following steps:
firstly, separating the pretreated biogas residue to obtain upper liquid and residual substrate: mixing 100kg of calcium, magnesium and silicon functional materials with hierarchical pore distribution with 1 ton of biogas residues, stirring for 15min, standing for 15min, separating upper-layer liquid, and using the remaining substrate as a mixture of the remaining calcium, magnesium and silicon functional materials and biogas residues; wherein the biogas residue is obtained by co-digesting a plurality of substrates such as livestock and poultry manure, straws and the like.
(II) dehydrating, drying and grinding the residual substrate to prepare substrate powder; in the embodiment, the residual substrate is put into a screw extruder to remove excessive water, and then is dried in a dryer for 12 hours, and the dried mixture is ground and then is sieved by a 60-mesh sieve to obtain substrate powder.
And (III) granulating the substrate powder to prepare the finished product of the low-heavy metal biogas residue composite silicon fertilizer. In this example, the substrate powder and the polyvinyl alcohol solution were mixed and pelletized in a pelletizer, in which polyvinyl alcohol is a binder. The mixture ratio of the substrate powder and the polyvinyl alcohol is 2.5kg/L, and the mass concentration of the polyvinyl alcohol solution is 10%. And drying the granulated granular composite organic silicon fertilizer in a dryer for 1h to obtain the low heavy metal biogas residue composite organic silicon fertilizer with the slow release function.
In this embodiment, the calcium, magnesium, and silicon functional material with hierarchical pore distribution is prepared as follows: (1) preparation of NaO. xSiO by alkali dissolution reaction2Solution: mixing the silicon-rich solid waste, sodium hydroxide and water to perform alkali dissolution reaction to obtain NaO xSiO2A solution;
in the embodiment, the alkali dissolution reaction temperature is 90 ℃, and the reaction time is 6 hours; the silicon-rich solid waste is coal gangue and diatomite; SiO in silicon-rich solid waste2The content is 35 wt%; the mass ratio of the silicon-rich solid waste to the sodium hydroxide is 1: 0.5; the mass ratio of total solids to water was 1: 5.
(2) Hydrothermal reaction for preparing xCaO yMgO zSiO2Suspension: in NaO. xSiO2Adding lime suspension and MgO suspension into the solution, mixing, and performing hydrothermal reaction to obtain xCaO.yMgO.z SiO2A suspension;
in this example, the hydrothermal reaction temperature was 150 ℃ and the reaction time was 7 hours. Lime suspension and NaO. xSiO2Mixing the solution according to the molar ratio of Ca to Si of 0.5; MgO suspension and NaO xSiO2Mixing the solution according to the Mg/Si molar ratio of 0.5; the solid-liquid ratio is 1: 20.
(3) And (3) carrying out suction filtration, washing and drying to obtain the calcium-magnesium-silicon functional material: xCaO yMgO zSiO2And (4) carrying out suction filtration, washing and drying on the suspension to obtain the calcium-magnesium-silicon functional material.
In the embodiment, the calcium, magnesium and silicon functional material is obtained after repeated washing three times, suction filtration and drying.
The calcium-magnesium-silicon functional material with hierarchical pore distribution prepared by the embodiment comprises the components of Ca, Si, Mg, O and H, and all the elements are available elements of the fertilizer, and can be independently used as a calcium-magnesium-silicon fertilizer.
The calcium-magnesium-silicon functional material with hierarchical pore distribution prepared in this embodiment is amorphous, has hierarchical pore distribution, and has pore diameters concentrated in three regions, which are: 2-10 nm; 10-30 nm; 30-300 nm trimodal distribution.
The calcium-magnesium-silicon functional material with the hierarchical pore distribution prepared by the embodiment has rich and developed pores. Specific surface area 150m2(ii)/g; total pore volume 0.432cm3(ii)/g; large specific surface area, rich surface charge, high cation exchange capacity and high adsorption capacity.
Example 3: the preparation method of the low heavy metal biogas residue composite organic silicon fertilizer with the slow release function comprises the following steps:
firstly, separating the pretreated biogas residue to obtain upper liquid and residual substrate: mixing 800kg of calcium, magnesium and silicon functional materials with hierarchical pore distribution with 8 tons of biogas residues, stirring for 100min, standing for 50min, and separating upper-layer liquid, wherein the residual substrate is a mixture of the residual calcium, magnesium and silicon functional materials and biogas residues; wherein the biogas residue is obtained by co-digesting a plurality of substrates such as livestock and poultry manure, straws and the like.
(II) dehydrating, drying and grinding the residual substrate to prepare substrate powder; in the embodiment, the residual substrate is put into a screw extruder to remove excessive water, and then is dried in a dryer for 12 hours, and the dried mixture is ground and then is sieved by a 60-mesh sieve to obtain substrate powder.
And (III) granulating the substrate powder to prepare the finished product of the low-heavy metal biogas residue composite silicon fertilizer. In this example, the substrate powder and the polyvinyl alcohol solution were mixed and pelletized in a pelletizer, in which polyvinyl alcohol is a binder. The mixture ratio of the substrate powder and the polyvinyl alcohol is 2.5kg/L, and the mass concentration of the polyvinyl alcohol solution is 10%. And drying the granulated granular composite organic silicon fertilizer in a dryer for 1h to obtain the low heavy metal biogas residue composite organic silicon fertilizer with the slow release function.
In this embodiment, the calcium, magnesium, and silicon functional material with hierarchical pore distribution is prepared as follows: (1) preparation of NaO. xSiO by alkali dissolution reaction2Solution: mixing the silicon-rich solid waste, sodium hydroxide and water to perform alkali dissolution reaction to obtain NaO xSiO2A solution;
in the embodiment, the alkali dissolution reaction temperature is 120 ℃, and the reaction time is 3 hours; silicon richThe solid waste is the combination of fly ash, micro silicon powder and coal gangue; SiO in silicon-rich solid waste2The content was 69 wt%; the mass ratio of the silicon-rich solid waste to the sodium hydroxide is 1: 1.5; the mass ratio of total solids to water was 1: 10.
(2) Hydrothermal reaction for preparing xCaO yMgO zSiO2Suspension: in NaO. xSiO2Adding lime suspension and MgO suspension into the solution, mixing, and performing hydrothermal reaction to obtain xCaO.yMgO.z SiO2A suspension;
in this example, the hydrothermal reaction temperature was 190 ℃ and the reaction time was 4 hours. Lime suspension and NaO. xSiO2Mixing the solution according to the molar ratio of Ca to Si of 2.0; MgO suspension and NaO xSiO2Mixing the solution according to the Mg/Si molar ratio of 2.0; the solid-liquid ratio is 1: 40.
(3) And (3) carrying out suction filtration, washing and drying to obtain the calcium-magnesium-silicon functional material: xCaO yMgO zSiO2And (4) carrying out suction filtration, washing and drying on the suspension to obtain the calcium-magnesium-silicon functional material.
In the embodiment, the calcium, magnesium and silicon functional material is obtained after repeated washing three times, suction filtration and drying.
The calcium-magnesium-silicon functional material with hierarchical pore distribution prepared by the embodiment comprises the components of Ca, Si, Mg, O and H, and all the elements are available elements of the fertilizer, and can be independently used as a calcium-magnesium-silicon fertilizer.
The calcium-magnesium-silicon functional material with hierarchical pore distribution prepared in this embodiment is amorphous, has hierarchical pore distribution, and has pore diameters concentrated in three regions, which are: 2-10 nm; 10-30 nm; 30-300 nm trimodal distribution.
The calcium-magnesium-silicon functional material with the hierarchical pore distribution prepared by the embodiment has rich and developed pores. Specific surface area 168m2(ii)/g; total pore volume 0.672cm3(ii)/g; large specific surface area, rich surface charge, high cation exchange capacity and high adsorption capacity.
Comparative example 1: a preparation method of calcium magnesium silicon functional material with hierarchical pore distribution is provided, wherein, the step (2) is hydrothermal reaction to prepare xCaO.yMgO.zSiO2Suspension: in NaO. xSiO2Adding lime into the solution for suspensionMixing the solution (without adding MgO suspension), and carrying out hydrothermal reaction to obtain suspension; in this example, the hydrothermal reaction temperature was 160 ℃ and the reaction time was 5 hours. Lime suspension and NaO. xSiO2Mixing the solution according to the molar ratio of Ca to Si of 1.2; the solid-liquid ratio is 1: 30. The other preparation methods were the same as in example 1. The material prepared in this comparative example, as shown in fig. 5a, has a multimodal pore size distribution structure.
Comparative example 2: a preparation method of calcium magnesium silicon functional material with hierarchical pore distribution is provided, wherein, the step (2) is hydrothermal reaction to prepare xCaO.yMgO.zSiO2Suspension: in NaO. xSiO2Adding lime suspension and MgO suspension into the solution, mixing, and performing hydrothermal reaction to obtain xCaO.yMgO.z SiO2A suspension; in this comparative example, the hydrothermal reaction temperature was 160 ℃ and the reaction time was 5 hours. Lime suspension and NaO. xSiO2Mixing the solution according to the molar ratio of Ca to Si of 1.2; MgO suspension and NaO xSiO2Mixing the solution according to the Mg/Si molar ratio of 0.1; the solid-liquid ratio is 1: 30. The other preparation methods were the same as in example 1. The material prepared in this comparative example, as shown in fig. 5b, has a multimodal pore size distribution structure.
Comparative example 3: a preparation method of calcium magnesium silicon functional material with hierarchical pore distribution is provided, wherein, the step (2) is hydrothermal reaction to prepare xCaO.yMgO.zSiO2Suspension: in NaO. xSiO2Adding lime suspension and MgO suspension into the solution, mixing, and performing hydrothermal reaction to obtain xCaO.yMgO.z SiO2A suspension; in this comparative example, the hydrothermal reaction temperature was 160 ℃ and the reaction time was 5 hours. Lime suspension and NaO. xSiO2Mixing the solution according to the molar ratio of Ca to Si of 1.2; MgO suspension and NaO xSiO2Mixing the solution according to the Mg/Si molar ratio of 3; the solid-liquid ratio is 1: 30. The other preparation methods were the same as in example 1. The material prepared in this comparative example, as shown in fig. 5c, has a multimodal pore size distribution structure.
Comparative example 4: a preparation method of calcium magnesium silicon functional material with hierarchical pore distribution is provided, wherein, the step (2) is hydrothermal reaction to prepare xCaO.yMgO.zSiO2Suspension: in NaO. xSiO2Adding lime suspension into the solution, and mixing (without adding lime suspension)MgO suspension) to perform hydrothermal reaction to obtain suspension; in this example, the hydrothermal reaction temperature was 150 ℃ and the reaction time was 7 hours. Lime suspension and NaO. xSiO2Mixing the solution according to the molar ratio of Ca to Si of 0.5; the solid-liquid ratio is 1: 20; the other preparation method is the same as that of example 2. The material prepared in this comparative example, as shown in fig. 5d, has a multimodal pore size distribution structure.
Comparative example 5: a preparation method of calcium magnesium silicon functional material with hierarchical pore distribution is provided, wherein, the step (2) is hydrothermal reaction to prepare xCaO.yMgO.zSiO2Suspension: in NaO. xSiO2Adding lime suspension into the solution, mixing (without adding MgO suspension), and carrying out hydrothermal reaction to obtain suspension; in this example, the hydrothermal reaction temperature was 190 ℃ and the reaction time was 4 hours. Lime suspension and NaO. xSiO2Mixing the solution according to the molar ratio of Ca to Si of 2.0; the other preparation methods are the same as example 3, and the solid-to-liquid ratio is 1: 40. The material prepared in this comparative example, as shown in fig. 5e, had a multimodal pore size distribution structure.
Comparative examples 1-5 further demonstrate that the amount of Mg added directly determines the pore distribution characteristics of the material and determines whether a multimodal pore size distribution structure is formed that facilitates adequate solid-liquid contact. When Mg element is not added or the Ca/Mg ratio is not designed reasonably, a multimodal pore size distribution structure which is beneficial to full contact of solid and liquid cannot be formed.
Comparative test example: the compound organosilicon fertilizer produced by the method of examples 1-3 was applied to pakchoi, and a comparative experiment was performed with the fertilizer. The soil to be tested is in a rural area which is expensive and special. The test fertilizers were the compound organosilicon fertilizers and commercial fertilizers (urea, diammonium phosphate, potassium sulfate) produced in examples 1-3 of the present invention, and the fertilizers were sprayed in the manner of base fertilizer and foliar topdressing. The application amount of urea is 11.2+0.35 kg/mu, the application amount of diammonium phosphate is 10.0+0.35 kg/mu, and the application amount of potassium sulfate is 4.2+0.35 kg/mu. The compound organic silicon fertilizer adopts two application modes: 150 kg/mu (low amount) and 200 kg/mu (high amount), and simultaneously, the concentrated biogas liquid separated from anaerobic residues is used as foliar fertilizer for spraying. The application of the high-quantity compound organic silicon fertilizer has obvious effect on the lodging resistance and the insect pest resistance of the pakchoi.
Meanwhile, the pH value and the effective silicon content of the soil to be tested in different periods are detected, the obtained results are shown in table 2, and the application of the compound organic silicon fertilizer has obvious effects of adjusting the pH value of the soil and improving the effective silicon content of the soil.
As shown in fig. 6, when the compound organic silicon fertilizer prepared in example 1 is applied, the effect of applying the low-amount compound organic silicon fertilizer on promoting the growth of pakchoi is equivalent to that of applying the chemical fertilizer, and the effect of applying the high-amount compound organic silicon fertilizer on promoting the growth of pakchoi is obviously better than that of applying the low-amount compound organic silicon fertilizer and the chemical fertilizer.
Further, in order to examine the reduction effect of the composite organic silicon fertilizer on heavy metal biotoxicity, a certain content of heavy metal cadmium is added into the tested pakchoi planting soil, the heavy metal cadmium content of the pakchoi harvested under different fertilization conditions is detected, and the obtained result is shown in table 3.
TABLE 1 detection of calcium, magnesium and silicon functional Material Components
Figure RE-GDA0003078648410000151
TABLE 2 effective silicon and pH values of pakchoi planting soil applied with different fertilizers
Figure RE-GDA0003078648410000152
Figure RE-GDA0003078648410000161
TABLE 3 cadmium content in pakchoi with different fertilizers
Figure RE-GDA0003078648410000162
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims (9)

1. The preparation method of the low heavy metal biogas residue composite organic silicon fertilizer with the slow release function is characterized by comprising the following steps:
firstly, separating the pretreated biogas residue to obtain upper liquid and residual substrate: mixing 100-800 kg of calcium-magnesium-silicon functional material with hierarchical pore distribution with 1-8 tons of biogas residues, stirring for 15-100 min, standing for 15-50 min, separating the upper layer liquid, and taking the residual substrate as a mixture of the residual calcium-magnesium-silicon functional material and biogas residues;
(II) dehydrating, drying and grinding the residual substrate to prepare substrate powder;
and (III) granulating the substrate powder to prepare the finished product of the low-heavy metal biogas residue composite silicon fertilizer.
2. The preparation method of the low heavy metal biogas residue composite organic silicon fertilizer with the slow release function according to claim 1, wherein the calcium, magnesium and silicon functional material with the hierarchical pore distribution is prepared by the following method:
(1) preparation of NaO. xSiO by alkali dissolution reaction2Solution: mixing the silicon-rich solid waste, sodium hydroxide and water to perform alkali dissolution reaction to obtain NaO xSiO2A solution;
(2) hydrothermal reaction for preparing xCaO yMgO zSiO2Suspension: in the NaO. xSiO2Adding lime suspension and MgO suspension into the solution, mixing, and performing hydrothermal reaction to obtain xCaO.yMgO.z SiO2A suspension;
(3) and (3) carrying out suction filtration, washing and drying to obtain the calcium-magnesium-silicon functional material: the xCaO yMgO zSiO2And carrying out suction filtration, washing and drying on the suspension to obtain the calcium-magnesium-silicon functional material with hierarchical pore distribution.
3. The preparation method of the low heavy metal biogas residue composite organic silicon fertilizer with the slow release function according to claim 2, wherein in the step (1), the mass ratio of the silicon-rich solid waste to the sodium hydroxide is 1: 0.5-1: 1.5; the mass ratio of the total solid to the water is 1: 5-1: 10.
4. The preparation method of the low heavy metal biogas residue composite organic silicon fertilizer with the slow release function according to claim 3, characterized in that SiO in the silicon-rich solid waste2The content is 35-70 wt%.
5. The preparation method of the low heavy metal biogas residue composite organic silicon fertilizer with the slow release function according to claim 4, wherein the silicon-rich solid waste is any one or a combination of more of fly ash, silica fume, coal gangue and diatomite.
6. The preparation method of the low heavy metal biogas residue composite organic silicon fertilizer with slow release function according to claim 2, characterized in that in the step (2), the lime suspension and the NaO. xSiO2Mixing the solutions according to the molar ratio of Ca to Si of 0.5-2.0; the MgO suspension and the NaO xSiO2Mixing the solution according to the Mg/Si molar ratio of 0.5-2.0; the solid-liquid ratio is 1: 20-1: 40.
7. The preparation method of the low-heavy-metal biogas residue composite organic silicon fertilizer with the slow release function according to claim 2, wherein in the step (1), the alkali dissolution reaction temperature is 90-120 ℃, and the reaction time is 3-6 h.
8. The preparation method of the low heavy metal biogas residue composite organic silicon fertilizer with the slow release function according to claim 2, wherein in the step (2), the hydrothermal reaction temperature is 150-190 ℃ and the reaction time is 4-7 h.
9. The low heavy metal biogas residue compound organic silicon fertilizer with the slow release function, which is prepared by the preparation method of the low heavy metal biogas residue compound organic silicon fertilizer with the slow release function of any one of claims 1 to 8.
CN202110307152.6A 2021-03-23 2021-03-23 Low-heavy-metal biogas residue composite organic silicon fertilizer with slow release function and preparation method thereof Pending CN113149753A (en)

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108314054A (en) * 2018-04-03 2018-07-24 山西玉竹新材料科技股份有限公司 A method of preparing microporous calcium silicate powder
CN109704837A (en) * 2018-12-21 2019-05-03 浙江大学 Using biogas residue after anaerobic fermentation as the organic-inorganic compound mixed fertilizer of raw material and preparation method
CN111908481A (en) * 2020-08-13 2020-11-10 内蒙古工业大学 Magnesium silicate material and preparation method and application thereof

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108314054A (en) * 2018-04-03 2018-07-24 山西玉竹新材料科技股份有限公司 A method of preparing microporous calcium silicate powder
CN109704837A (en) * 2018-12-21 2019-05-03 浙江大学 Using biogas residue after anaerobic fermentation as the organic-inorganic compound mixed fertilizer of raw material and preparation method
CN111908481A (en) * 2020-08-13 2020-11-10 内蒙古工业大学 Magnesium silicate material and preparation method and application thereof

Non-Patent Citations (5)

* Cited by examiner, † Cited by third party
Title
LUCIE GALVÁNKOVÁ 等: "Tobermorite synthesis under hydrothermal conditions", 《PROCEDIA ENGINEERING》 *
MADDALENA 等: "Direct synthesis of a solid calcium-silicate-hydrate (C-S-H)", 《CONSTRUCTION AND BUILDING MATERIALS》 *
NINGNING SHAO 等: "Hierarchically Structured Calcium Silicate Hydrate-Based Nanocomposites Derived from Steel Slag for Highly Efficient Heavy Metal Removal from Wastewater", 《ACS SUSTAINABLE CHEM. ENG.》 *
YUE ZHAO 等: "Enhanced phosphate removal during the simultaneous adsorption of phosphate and Ni2+ from electroless nickel wastewater by calcium silicate hydrate (CSH)", 《ENVIRONMENTAL TECHNOLOGY & INNOVATION》 *
包亚莉等: "新型硅基分级孔材料的制备及其孔隙结构", 《天津大学学报(自然科学与工程技术版)》 *

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