Livestock and poultry manure nitrogen conservation and odor synergistic composite conditioner and preparation method

Abstract

The application discloses a livestock and poultry manure nitrogen conservation and odor synergistic composite conditioner and a preparation method thereof. The composite conditioner comprises an adsorption unit, an acidification unit, a microbial inhibition unit, a functional microbial agent and a skeleton filler. The adsorption unit is a compound of modified biochar and zeolite powder. The acidification unit is a mixture of citric acid and ferrous sulfate. The microbial inhibition unit is a mixture of cinnamyl aldehyde and D-amino acid. The functional microbial agent is a mixture of nitrifying bacteria, denitrifying bacteria and sulfur bacillus. The preparation steps include phosphoric acid activation to prepare modified biochar, pre-mixing of the acidification unit, low-temperature fusion granulation and drying and screening. Through physical adsorption, chemical precipitation, targeted microbial inhibition and functional microbial regulation, the application realizes the improvement of the retention rate of ammonium nitrogen in manure to more than 85%, and simultaneously greatly reduces the emission of ammonia and hydrogen sulfide, and is suitable for source conditioning of livestock and poultry breeding farm manure and clean production of organic fertilizer.

Description

Technical Field

[0001] This invention belongs to the field of organic waste resource utilization technology, specifically relating to a nitrogen retention and odor synergistic compound conditioner for livestock and poultry manure and its preparation method. Background Technology

[0002] With the rapid development of livestock and poultry farming towards large-scale and intensive operations, the centralized discharge of livestock and poultry manure at the farming end generates massive amounts of manure, increasing the pressure on harmless disposal and resource-based quality improvement at the downstream end. During the entire process of temporary storage, static composting, and large-scale composting, the endogenous nitrogen-containing organic matter undergoes rapid mineralization reactions under the combined action of indigenous microbial metabolism and urease, generating large amounts of free ammonium nitrogen. This reactive nitrogen is highly susceptible to rapid conversion into ammonia gas and loss due to fluctuations in ambient temperature and pH, directly causing a significant reduction in the organic fertilizer capacity of the manure and a precipitous drop in nutrient utilization. Simultaneously, the continuous emission and diffusion of complex odorous pollutants such as ammonia and hydrogen sulfide, after accumulation, induces secondary environmental problems such as odor disturbances and excessive aerosol levels in the surrounding area, directly hindering the compliant and normalized production of farms, and exhibiting poor ecological adaptability and compatibility with public welfare.

[0003] To address these issues, existing technologies often employ the addition of physical or chemical nitrogen-fixing agents such as superphosphate and zeolite, or the addition of biological agents such as sodium humate. However, traditional methods generally suffer from common drawbacks, including limited functionality, poor adaptability to various operating conditions, and poor synergistic matching of multiple effects: while physical adsorbents can temporarily retain ammonium ions, their effect on controlling sulfur-based odors is weak; while acidifiers can lower the local pH to inhibit ammonia volatilization, excessive use may suppress the overall activity of composting microorganisms, slowing down the temperature rise and maturation process of manure; single biological inhibitors are often only effective against specific gas-producing bacteria, with narrow adaptability profiles and poor stress resistance, making it difficult to achieve simultaneous control of multiple odorous gases. Furthermore, existing conditioners rarely involve the targeted regulation of functional microorganisms, failing to achieve efficient storage and retention along the nitrogen conversion pathway.

[0004] Therefore, there is an urgent need to develop a composite conditioner that can simultaneously achieve multi-pathway targeted odor control, directional nitrogen retention, and in-situ microecological regulation in a synergistic manner. This would address the shortcomings of existing single-regulation technologies, and meet the dual needs of improving the quality and efficiency of manure resource utilization and the clean and low-odor management of farm areas. This would be of great significance for promoting the resource utilization and clean production of livestock and poultry manure. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a synergistic compound conditioner for nitrogen retention and odor control in livestock and poultry manure, along with its preparation method. This conditioner achieves efficient nitrogen fixation and significant reductions in ammonia and hydrogen sulfide emissions simultaneously through a multi-pathway synergistic effect involving physical adsorption, chemical precipitation, targeted microbial inhibition, and functional microbial regulation.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] In a first aspect, the present invention provides a nitrogen retention and odor synergistic compound conditioner for livestock and poultry manure, comprising the following components by weight:

[0008] Adsorption unit 30-60 parts, acidification unit 10-25 parts, microbial inhibition unit 5-15 parts, functional microbial agent unit 2-10 parts, skeleton filler 10-30 parts;

[0009] The adsorption unit is composed of modified biochar and zeolite powder in a mass ratio of 2-4:1.

[0010] The acidification unit is composed of citric acid and ferrous sulfate in a mass ratio of 1:0.5-2;

[0011] The microbial inhibition unit is composed of cinnamaldehyde and D-type amino acids in a mass ratio of 1:0.3-1;

[0012] The functional microbial agent unit is composed of nitrifying bacteria, denitrifying bacteria, and thiobacillus in a mass ratio of 1-3:1-2:1;

[0013] The skeleton filler is bentonite.

[0014] Preferably, the modified biochar is prepared by: soaking corn straw char in a phosphoric acid solution with a mass fraction of 8%-12% for 6-10 hours, taking it out and pyrolyzing it in a nitrogen atmosphere at 500-600℃ for 1-2 hours, cooling it and washing it with water until the pH is 5.5-6.5, drying it and grinding it through an 80-mesh sieve.

[0015] Preferably, the zeolite powder is clinoptilolite powder with a particle size of 100-200 mesh and a specific surface area ≥300m² / g; the bentonite is sodium-based bentonite with a montmorillonite content ≥75%.

[0016] Preferably, the D-type amino acid is at least one of D-aspartic acid or D-glutamic acid.

[0017] Preferably, the nitrifying bacteria, denitrifying bacteria, and thiobacilli are all heat-resistant strains that have been selectively isolated from high-temperature composting environments and can withstand composting temperatures of 55–60°C.

[0018] Preferably, the composite conditioner is a spherical particle with a particle size of 0.5-2 mm, a moisture content of ≤5%, and an angle of repose of ≤35°.

[0019] Secondly, the present invention provides a method for preparing the aforementioned nitrogen retention and odor synergistic compound conditioner for livestock and poultry manure, comprising the following steps:

[0020] Step A: Soak corn straw charcoal in a phosphoric acid solution with a mass fraction of 8%-12% for 6-10 hours, remove it and pyrolyze it at 500-600℃ under a nitrogen atmosphere for 1-2 hours. After cooling, wash it with water until the pH is 5.5-6.5, dry it and grind it through an 80-mesh sieve to prepare modified biochar.

[0021] Step B: Weigh citric acid and ferrous sulfate according to the ratio, add 0.8-1.2 times the total mass of the two in deionized water, stir to dissolve, and obtain an acidified mixture;

[0022] Step C: Add the adsorption unit, the microbial inhibition unit, the functional microbial agent unit and the skeleton filler into the mixer and stir at 200-400 rpm for 10-15 minutes; keep the material temperature at 15-25℃, and spray the acidified mixture into the mixture while stirring, and continue stirring until wet particles are formed;

[0023] Step D: Vacuum dry the wet granules at 35-45℃ until the moisture content is ≤5%, and sieve to obtain 0.5-2mm granules.

[0024] Preferably, in step C, the nozzle pressure for atomization is 0.2-0.4 MPa, and the spraying time is 5-8 minutes.

[0025] Preferably, the drying in step D is performed using a double-cone rotary vacuum dryer with a vacuum degree of -0.06 to -0.09 MPa, a rotation speed of 5-10 rpm, and a temperature of 35-45℃.

[0026] Thirdly, the present invention provides the application of the nitrogen retention and odor synergistic compound conditioner for livestock and poultry manure in the treatment of livestock and poultry manure. The compound conditioner is directly added to fresh livestock and poultry manure at a ratio of 2%-6% of the total mass of manure, mixed evenly, and then piled up or put into a fermentation system.

[0027] Preferably, the mixing is carried out using a horizontal double-ribbon mixer with a mixing frequency of 30-50Hz and a mixing time of 5-10 minutes; the mixed material is then composted in windrows or troughs within 4-8 hours.

[0028] Compared with the prior art, the present invention provides a nitrogen retention and odor synergistic compound conditioner for livestock and poultry manure and its preparation method, which has the following beneficial effects:

[0029] 1. This invention is the first to integrate physical adsorption (modified biochar, zeolite), chemical precipitation and ammonia inhibition through acidification (citric acid, ferrous sulfate), microbial metabolic inhibition (cinnamaldehyde, D-amino acids), and synergistic metabolism by functional microorganisms (nitrifying bacteria, denitrifying bacteria, thiobacilli) into a single conditioner, forming a four-level synergistic network of "adsorption-precipitation-biological transformation". Experiments show that after adding this conditioner, the 30-day retention rate of ammonium nitrogen in fecal waste can reach over 85%, the peak ammonia emission reduction rate is ≥70%, and the peak hydrogen sulfide emission reduction rate is ≥85%, significantly better than the simple summation of the individual functional units.

[0030] 2. The highest temperature during the entire preparation process of this invention does not exceed 45℃. It adopts low-temperature fusion granulation and vacuum drying technology, which can maximize the preservation of the activity of cinnamaldehyde, D-type amino acids and functional microbial agents, with a functional microbial survival rate of ≥90%. At the same time, the acidification unit, adsorption unit and skeleton filler work together to create a suitable microenvironment for functional microorganisms, avoiding damage to the strains caused by the high temperature of 55-60℃ and extreme pH of compost, thus ensuring their activity stability. The finished product is a granule, which is dust-free, has good flowability, and an angle of repose of ≤35°, making it convenient for automated feeding and application.

[0031] 3. The raw materials used in this invention are all food-grade, feed-grade, or natural minerals, and do not contain heavy metals or other toxic or harmful substances. The ferrous sulfate in the conditioner can eventually be converted into stable iron oxide or iron oxide minerals during the later stages of composting or after application to the soil, without causing secondary environmental pollution. The introduced functional microorganisms can synergistically accelerate nitrogen conversion and reduce nitrous oxide emissions. Attached Figure Description

[0032] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0033] Figure 1 This is a schematic diagram of the preparation process of the nitrogen retention and odor synergistic compound conditioner for livestock and poultry manure proposed in this invention;

[0034] Figure 2 This is a diagram illustrating the synergistic mechanism between the various functional units of this invention;

[0035] Figure 3 This is a dynamic change curve of ammonium nitrogen retention rate according to an embodiment of the present invention;

[0036] Figure 4 This is a graph showing the change in peak ammonia emission reduction rate according to an embodiment of the present invention.

[0037] Figure 5 This is a graph showing the change in peak hydrogen sulfide emission reduction rate according to an embodiment of the present invention. Detailed Implementation

[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] All specific values, material types, and process parameters involved in this embodiment are illustrative examples used to clearly demonstrate the technical operation process and are not the only limitation of the present invention.

[0040] Please see Figures 1-5 .

[0041] Example 1

[0042] This embodiment provides a nitrogen retention and odor synergistic compound conditioner for livestock and poultry manure and its preparation method.

[0043] A compound conditioner for nitrogen retention and odor control in livestock and poultry manure, comprising the following components by weight:

[0044] Adsorption unit: 40 parts

[0045] The mass ratio of modified biochar to zeolite powder is 3:1, that is, 30 parts of modified biochar and 10 parts of zeolite powder.

[0046] Acidification unit: 18 parts

[0047] The mass ratio of citric acid to ferrous sulfate is 1:1, that is, 9 parts citric acid and 9 parts ferrous sulfate.

[0048] Microbial inhibition unit: 10 copies

[0049] The mass ratio of cinnamaldehyde to D-aspartic acid is 1:0.6, that is, 6.25 parts of cinnamaldehyde and 3.75 parts of D-aspartic acid.

[0050] Functional microbial inoculant unit: 6 portions

[0051] It is a mixture of nitrifying bacteria, denitrifying bacteria, and thiobacilli in a mass ratio of 2:1.5:1. The total number of viable bacteria is ≥1×10^9 CFU / g.

[0052] Skeleton filler: 26 parts

[0053] It is sodium-based bentonite, with a measured montmorillonite content of 78%.

[0054] A method for preparing a synergistic compound conditioner for nitrogen retention and odor control in livestock and poultry manure includes the following steps:

[0055] Corn stalk charcoal (commercially available or homemade, obtained by preliminary carbonization of corn stalks under limited oxygen conditions at 400℃) was impregnated in a 10% (w / w) phosphoric acid solution for 8 hours. Stirring was performed every 2 hours during impregnation to ensure full activation. After removal, it was pyrolyzed at 550℃ under a nitrogen atmosphere for 1.5 hours at a nitrogen flow rate of 0.5 L / min. After cooling to room temperature, it was repeatedly washed with deionized water until the pH reached 6.0. Then, it was dried at 105℃ to constant weight, ground, and passed through an 80-mesh sieve to obtain modified biochar. The modified biochar had a specific surface area of ​​520 m² / g and a total pore volume of 0.45 cm³ / g.

[0056] The zeolite powder is clinoptilolite powder with a particle size of 150 mesh and a measured specific surface area of ​​320 m² / g. The bentonite is sodium-based bentonite with a montmorillonite content of 78% and a colloidal value ≥85 mL / 15g.

[0057] Step S1: Prepare modified biochar according to the above method of "Preparation of Modified Biochar", and then mix it with zeolite powder at a mass ratio of 3:1 to obtain an adsorption unit for later use.

[0058] Step S2: Weigh out 9 parts citric acid and 9 parts ferrous sulfate, add 1.0 times their total mass of deionized water (i.e., 18 parts deionized water), and stir with a magnetic stirrer at 500 rpm for 15 minutes until completely dissolved to obtain an acidified mixture. This mixture is a light green transparent liquid with a pH of approximately 2.5.

[0059] Step S3: Add 40 parts of the adsorption unit, 10 parts of the microbial inhibition unit (cinnamaldehyde and D-aspartic acid premixed evenly), 6 parts of the functional microbial agent unit, and 26 parts of the skeleton filler obtained in Step S1 into a horizontal plow mixer. Close the feed gate, start stirring, and stir at 300 rpm for 12 minutes to ensure that the materials are initially mixed evenly. Control the material temperature at 20℃ using jacket cooling water. Under continuous stirring, spray the acidified mixture obtained in Step S2 into the mixer using a high-pressure atomizing nozzle. Set the nozzle pressure to 0.3 MPa and the spraying time to 6 minutes. The atomized droplet diameter is approximately 50-100 μm. After spraying, continue stirring for 3 minutes until wet particles that can be formed into a clump when squeezed but crumble easily when touched are formed. At this point, the moisture content of the wet particles is approximately 25%-30%.

[0060] Step S4: Transfer the wet granules obtained in Step S3 to a double-cone rotary vacuum dryer. Set the vacuum level to -0.08 MPa, the rotation speed to 8 rpm, and the drying temperature to 40℃ (to ensure the activity of the functional microbial agent, the temperature should not exceed 45℃). The drying time is 2.5 hours, during which samples are taken every 30 minutes to check the moisture content until the moisture content is ≤5%. The moisture content of the dried granules is measured to be 4.2%. Then, use a vibrating sieve to sieve and collect spherical granules with a particle size in the range of 0.5-2 mm to obtain the finished product. The fine powder undersize can be returned to the mixer for regranulation, and the large particles on the sieve can be crushed and sieved again.

[0061] The finished product consists of dark gray spherical granules with a particle size of 0.5-2 mm, a moisture content of 4.2%, an angle of repose of 32° (measured using the injection method), and a particle strength ≥8 N. The survival rate of the functional microbial agent was determined to be 92% using the dilution plate count method.

[0062] Example 2

[0063] This embodiment provides another formulation of a nitrogen retention and odor synergistic compound conditioner for livestock and poultry manure and its preparation method.

[0064] A compound conditioner for nitrogen retention and odor control in livestock and poultry manure, comprising the following components by weight:

[0065] Adsorption unit: 30 parts

[0066] The mass ratio of modified biochar to zeolite powder is 2:1, that is, 20 parts of modified biochar and 10 parts of zeolite powder.

[0067] Acidification unit: 25 parts

[0068] The mass ratio of citric acid to ferrous sulfate is 1:2, that is, 8.33 parts of citric acid and 16.67 parts of ferrous sulfate.

[0069] Microbial inhibition unit: 15 copies

[0070] The mass ratio of cinnamaldehyde to D-glutamic acid is 1:1, that is, 7.5 parts of cinnamaldehyde and 7.5 parts of D-glutamic acid.

[0071] Functional microbial inoculant unit: 10 portions

[0072] It is a mixture of nitrifying bacteria, denitrifying bacteria and thiobacilli in a mass ratio of 3:2:1, with a total viable count ≥1.5×10^9 CFU / g.

[0073] Skeleton filler: 20 parts

[0074] Sodium-based bentonite, with a montmorillonite content of 80%.

[0075] A method for preparing a synergistic compound conditioner for nitrogen retention and odor control in livestock and poultry manure includes the following steps:

[0076] Corn stalk charcoal was impregnated in an 8% (w / w) phosphoric acid solution for 10 hours. After removal, it was pyrolyzed at 500℃ under a nitrogen atmosphere for 2 hours at a nitrogen flow rate of 0.6 L / min. After cooling, it was washed with water until pH 5.5, dried, and ground through an 80-mesh sieve. The modified biochar had a specific surface area of ​​485 m² / g.

[0077] The zeolite powder is clinoptilolite powder with a particle size of 100 mesh and a specific surface area of ​​300 m² / g. The bentonite is sodium-based bentonite with a montmorillonite content of 80%.

[0078] Step S1: Prepare modified biochar according to the above method, and mix it with zeolite powder at a mass ratio of 2:1 to obtain an adsorption unit.

[0079] Step S2: Weigh 8.33 parts of citric acid and 16.67 parts of ferrous sulfate, add 0.8 times the total mass of the two in deionized water (i.e., 20 parts of deionized water), stir to dissolve, and obtain an acidified mixture.

[0080] Step S3: Add 30 parts of the adsorption unit, 15 parts of the microbial inhibition unit (cinnamaldehyde and D-glutamic acid premixed), 10 parts of the functional microbial agent unit, and 20 parts of the skeleton filler to the mixer. Stir at 200 rpm for 15 minutes. Maintain the material temperature at 15°C. While continuously stirring, spray the acidified mixture into the mixture through an atomizing nozzle at a pressure of 0.2 MPa over 8 minutes. Continue stirring until wet granules are formed.

[0081] Step S4: Place the wet granules in a double-cone rotary vacuum dryer at a vacuum of -0.09 MPa, a rotation speed of 5 rpm, and a temperature of 35°C (low temperature to protect the bacterial agent) until the moisture content is ≤5%. The moisture content was measured to be 4.8%. Collect 0.5-2 mm granules by sieving.

[0082] Spherical particles with a moisture content of 4.8%, an angle of repose of 34°, a particle strength of 7.5N, and a functional microbial survival rate of 90%.

[0083] Example 3

[0084] This embodiment provides another formulation of a nitrogen retention and odor synergistic compound conditioner for livestock and poultry manure and its preparation method.

[0085] A compound conditioner for nitrogen retention and odor control in livestock and poultry manure, comprising the following components by weight:

[0086] Adsorption unit: 50 parts

[0087] The mass ratio of modified biochar to zeolite powder is 4:1, that is, 40 parts of modified biochar and 10 parts of zeolite powder.

[0088] Acidification unit: 12 parts

[0089] The mass ratio of citric acid to ferrous sulfate is 1:0.5, that is, 8 parts citric acid and 4 parts ferrous sulfate.

[0090] Microbial inhibition unit: 5 units

[0091] The mass ratio of cinnamaldehyde to D-aspartic acid is 1:0.3, that is, 3.85 parts of cinnamaldehyde and 1.15 parts of D-aspartic acid.

[0092] Functional microbial inoculant unit: 3 portions

[0093] It is a mixture of nitrifying bacteria, denitrifying bacteria and thiobacilli in a mass ratio of 1:1:1, with a total viable count ≥0.8×10^9 CFU / g.

[0094] Skeleton filler: 30 parts

[0095] Sodium-based bentonite with 75% montmorillonite content.

[0096] A method for preparing a synergistic compound conditioner for nitrogen retention and odor control in livestock and poultry manure includes the following steps:

[0097] Corn stalk charcoal was impregnated in a 12% (w / w) phosphoric acid solution for 6 hours. After removal, it was pyrolyzed at 600℃ under a nitrogen atmosphere for 1 hour at a nitrogen flow rate of 0.4 L / min. After cooling, it was washed with water until pH 6.5, dried, and ground through an 80-mesh sieve. Specific surface area: 550 m² / g.

[0098] The zeolite powder is clinoptilolite powder with a particle size of 200 mesh and a specific surface area of ​​350 m² / g. The bentonite is sodium-based bentonite with a montmorillonite content of 75%.

[0099] Step S1: Prepare modified biochar according to the above method, and mix it with zeolite powder at a mass ratio of 4:1 to obtain an adsorption unit.

[0100] Step S2: Weigh 8 parts of citric acid and 4 parts of ferrous sulfate, add 1.2 times the total mass of the two in deionized water (i.e., 14.4 parts of deionized water), stir to dissolve, and obtain an acidified mixture.

[0101] Step S3: Add 50 parts of the adsorption unit, 5 parts of the microbial inhibition unit (a mixture of cinnamaldehyde and D-aspartic acid), 3 parts of the functional microbial agent unit, and 30 parts of the skeleton filler to the mixer. Stir at 400 rpm for 10 minutes. Maintain the material temperature at 25°C. Atomize and spray the acidified mixture into the solution at a nozzle pressure of 0.4 MPa for 5 minutes. Stir until wet granules are formed.

[0102] Step S4: Place the wet granules in a double cone rotary vacuum dryer at a vacuum of -0.06 MPa, a rotation speed of 10 rpm, and a temperature of 45°C until the moisture content is ≤5%. The moisture content is measured to be 4.5%. Sieve the 0.5-2 mm granules.

[0103] Spherical particles with a moisture content of 4.5%, an angle of repose of 33°, a particle strength of 8.2N, and a functional microbial survival rate of 91%.

[0104] Comparative Example 1 (Single Adsorption Type)

[0105] This comparative example is used to verify the synergistic effect of the multi-unit components in this invention.

[0106] Formulation: Contains only 45 parts of adsorption unit, wherein the mass ratio of modified biochar to zeolite powder is 3:1 (the preparation method of modified biochar is the same as in Example 1). No acidification unit, microbial inhibition unit, functional microbial agent unit, or skeleton filler is added.

[0107] Preparation method: Modified biochar and zeolite powder are mixed in a certain proportion and stirred at 300 rpm for 12 minutes to obtain a powdery mixture. No acidification or granulation steps are performed. The product is a powdery mixture with an angle of repose of 48°, and is prone to dust generation.

[0108] Comparative Example 2 (Single Acidification Type)

[0109] Formula: Contains only 18 parts of the acidification unit, wherein the mass ratio of citric acid to ferrous sulfate is 1:1 (same as in Example 1). No other units are added.

[0110] Preparation method: Weigh 9 parts citric acid and 9 parts ferrous sulfate, add 18 parts deionized water to dissolve, and stir evenly. Spray dry the solution using a spray dryer with an inlet air temperature of 120℃ and an outlet air temperature of 60℃ to obtain solid granules. The product is light yellow granules with uneven particle size and contains no adsorbent or microbial inhibitory components.

[0111] Comparative Example 3 (Single Microorganism Inhibition Type)

[0112] Formulation: Contains only 10 parts of the microbial inhibition unit, wherein the mass ratio of cinnamaldehyde to D-aspartic acid is 1:0.6 (same as in Example 1). No other units are added.

[0113] Preparation method: Cinnamaldehyde and D-aspartic acid were mixed in a certain proportion, and an appropriate amount of anhydrous ethanol (approximately 30% of the total mass of the mixture) was added as a dispersant. The mixture was wet-milled in a colloid mill for 30 minutes. Then, the ethanol was removed by vacuum evaporation in a 40°C water bath to obtain a paste-like mixture. The product is a pale yellow paste that is not easily mixed evenly with feces.

[0114] Comparative Example 4 (Non-functional microbial inoculant)

[0115] This comparative example is used to verify the necessity of functional microbial agent units.

[0116] Formula: Except for the absence of the functional microbial agent unit, it is completely identical to Example 1. Specifically, it contains 40 parts of adsorption unit (modified biochar: zeolite powder = 3:1), 18 parts of acidification unit (citric acid: ferrous sulfate = 1:1), 10 parts of microbial inhibition unit (cinnamaldehyde: D-aspartic acid = 1:0.6), and 32 parts of skeleton filler (to fill the 6 missing parts). The total weight remains 100 parts.

[0117] Preparation method: Same as steps S1 to S4 in Example 1, with the drying temperature remaining at 40°C. Spherical particles were obtained with a moisture content of 4.3% and an angle of repose of 32°.

[0118] To comprehensively evaluate the performance of this invention, five testing points were set: 0 days, 7 days, 14 days, 21 days, and 30 days. The testing indicators included:

[0119] Ammonium nitrogen content: determined by indophenol blue colorimetric method.

[0120] Ammonia emission concentration: A portable ammonia detector (resolution 0.1ppm) was used to measure the concentration at a distance of 15cm above the surface of the pile. Measurements were taken twice a day, at 10:00 AM and 4:00 PM, and the peak value was recorded.

[0121] Hydrogen sulfide emission concentration: The hydrogen sulfide detector (resolution 0.1 ppm) was used, and the measurement method was the same as above.

[0122] Blank control group: Fresh feces without any conditioner added.

[0123] Composting conditions: Windlass composting, turning the pile every 5 days, initial moisture content of the pile controlled at around 60%, and carbon-to-nitrogen ratio (C / N) adjusted to 25:1. The amount of manure added in each example and comparative example is 4% of the total mass of manure (dry basis), and composting begins after thorough mixing.

[0124] The conditioner prepared in Example 1 was applied to fresh pig manure, fresh cow manure (ruminant, rich in microorganisms), and fresh chicken manure (poultry), respectively, and the above-mentioned dynamic tests were performed. The results are as follows.

[0125] Table 1. Dynamic changes in ammonium nitrogen retention rate under different types of fecal waste (unit: %)

[0126] pig manure Add Example 1 100 92.3 88.7 86.2 85.9 pig manure Blank control 100 65.2 48.6 37.5 31.2 cow dung Add Example 1 100 90.8 86.5 83.9 83.1 cow dung Blank control 100 57.3 43.1 36 28.9 chicken manure Add Example 1 100 91.2 87.3 84.6 84 chicken manure Blank control 100 55.2 40.3 32.9 25.4

[0127] Table 2. Ammonia peak emission reduction rate under different types of sewage (relative to the control group, unit: %)

[0128] pig manure 68.5 73.2 71 65.8 cow dung 62.1 67.5 65.3 60.2 chicken manure 65.7 70.1 68.2 63.5

[0129] Table 3. Peak hydrogen sulfide emission reduction rate under different types of fecal waste (relative to the control group, unit: %)

[0130] pig manure 82.3 88.6 86.1 81.5 cow dung 78.5 84.2 82 77.8 chicken manure 80.1 86.7 84.3 79.6

[0131] Results Analysis: The conditioner of this invention exhibited significant nitrogen retention and odor reduction effects in all three types of manure. Pig manure showed the best effect, while cow manure, due to its richer native microorganisms, showed a slight decrease in the effects of acidification and inhibition units, but was still significantly better than its control group. Chicken manure showed intermediate effects. Dynamic curves showed that the ammonium nitrogen retention rate decreased rapidly in the first 14 days, then leveled off; the peak emission reduction rates of ammonia and hydrogen sulfide occurred between days 7 and 14, coinciding with the composting warming period, during which the conditioner's inhibitory effect was most effective.

[0132] Performance comparison of each embodiment and comparative example (using pig manure as substrate, 30-day data).

[0133] Following the dynamic detection method described above, Examples 1-3 and Comparative Examples 1-4 were added to fresh pig manure, and the ammonium nitrogen retention rate, ammonia peak emission reduction rate, and hydrogen sulfide peak emission reduction rate were recorded after 30 days. The results are shown in Table 4.

[0134] Table 4. Performance comparison of various samples (pig manure, 30 days)

[0135] sample Ammonium nitrogen retention rate (%) Ammonia reduction rate (%) Hydrogen sulfide reduction rate (%) Example 1 87.5 73.2 88.6 Example 2 85.6 70.8 86.1 Example 3 86.3 71.5 87.3 Comparative Example 1 54.6 28.5 31.2 Comparative Example 2 72.1 61.4 78.5 Comparative Example 3 48.2 19.6 22.8 Comparative Example 4 79.8 65.3 75.4

[0136] Results analysis:

[0137] It can be seen from the above table:

[0138] In Examples 1-3, the ammonium nitrogen retention rate was over 85%, the ammonia reduction rate was over 70%, and the hydrogen sulfide reduction rate was over 85%. The composite process showed a significant synergistic effect in nitrogen retention and deodorization.

[0139] Although Comparative Example 1 (single adsorption) could temporarily adsorb some NH4⁺, it could not inhibit microbial gas production and had limited adsorption capacity. After 30 days, the ammonium nitrogen retention rate was only 54.6%, and the ammonia and hydrogen sulfide reduction rates were only 28.5% and 31.2%, respectively, which was a poor effect.

[0140] Comparative Example 2 (single acidification) suppressed some ammonia volatilization by lowering the pH and precipitated some sulfides with Fe²⁺, but it could not retain the generated ammonium ions and the acidification effect was not durable. After 30 days, the ammonium nitrogen retention rate was 72.1%, which was still significantly lower than that of the Example Group.

[0141] Comparative Example 3 (single inhibition) could inhibit urease activity, but could not treat existing free ammonia and sulfides. After 30 days, the ammonium nitrogen retention rate was only 48.2%, and the ammonia and hydrogen sulfide reduction rates were only 19.6% and 22.8%, respectively. All performance indicators were the lowest among all samples, and the effect was the worst.

[0142] Comparative Example 4 (without functional microbial agent) showed an ammonium nitrogen retention rate of 79.8%, an ammonia reduction rate of 65.3%, and a hydrogen sulfide reduction rate of 75.4% after 30 days. Although these were better than the individual additive comparative examples, they were still lower than the example group. This indicates that the combined use of functional microorganisms and other additives can further improve nitrogen conversion efficiency (converting some ammonium nitrogen into nitrate nitrogen or nitrogen gas, reducing the generation and emission of ammonia gas).

[0143] Calculations showed that all indicators in Examples 1-3 were significantly higher than the arithmetic mean of the corresponding indicators in Comparative Examples 1-4, proving that the four-level synergy of "adsorption-precipitation-inhibition-biotransformation" has a significant synergistic effect, rather than a simple functional superposition.

[0144] Application Example 1

[0145] In a large-scale pig farm with a stock of 5,000 pigs, the compound conditioner prepared in Example 1 was added directly to the newly cleaned manure at a ratio of 5% of the total mass of fresh pig manure via a belt conveyor. The initial moisture content of the manure was approximately 75%, and the total nitrogen content was approximately 0.8% (dry basis). A horizontal twin-ribbon mixer was used to mix the manure for 6 minutes at a frequency of 50 Hz to ensure full contact between the conditioner and the manure. The uniformly mixed material was then transferred to a trough-type composting fermentation tank (50 m long, 6 m wide, and 2 m high) for aerobic composting, with forced ventilation (ventilation rate of 0.2 m³ / min·m³), and the compost was turned over every 5 days.

[0146] Dynamic monitoring results (detection points 0, 7, 14, 21, and 30 days): Ammonium nitrogen retention rate: 31.2% in the control group and 86.5% in the conditioner-added group. Ammonia peak emission: 85 ppm in the control group and 21 ppm in the conditioner-added group, a reduction rate of 75.3%. Hydrogen sulfide peak emission: 32 ppm in the control group and 3.2 ppm in the conditioner-added group, a reduction rate of 90.0%. Compost product quality: After 30 days of fermentation, the compost product maturity (germination index) was 92%, and the total nutrient content (N+P2O5+K2O) was 5.8%, an increase of 18% compared to the 4.9% in the control group. Heavy metal content met the NY / T525-2021 standard (As≤15mg / kg, Pb≤50mg / kg, Cd≤3mg / kg, Cr≤150mg / kg, Hg≤2mg / kg). The finished product has no foul odor, is dark brown in color, and is loose without clumping.

[0147] Application Example 2

[0148] In a dairy farm with 800 cows, the conditioner prepared in Example 2 was added at a ratio of 4% of the total mass of fresh cow manure. The initial pH of the cow manure was 8.2, total nitrogen was 0.6% (dry basis), and moisture content was 80%. A horizontal twin-ribbon mixer (40Hz, 8 minutes) was used for mixing, followed by windrow composting (2m wide, 1.5m high), with the compost piles turned twice a week.

[0149] Dynamic monitoring results (detection points 0, 7, 14, 21, and 30 days): Ammonium nitrogen retention rate after 30 days: 28.9% in the control group and 86.5% in the conditioner-added group. Peak ammonia emissions: 85 ppm in the control group and 21 ppm in the conditioner-added group, a reduction rate of 75.3%. Peak hydrogen sulfide emissions: 32 ppm in the control group and 3.2 ppm in the conditioner-added group, a reduction rate of 90.0%. Compost product: After 30 days, the compost was fully decomposed, odorless, with a germination index of 88% and a total nutrient content (N+P2O5+K2O) of 5.8%, an increase of 18% compared to the 4.9% in the control group. Due to the rich initial microorganisms in cow manure, the inhibitory and functional microbial units of the conditioner synergistically controlled the odor.

[0150] Application Example 3

[0151] In a laying hen farm with 100,000 chickens, the conditioner prepared in Example 3 was added at a ratio of 6% of the total mass of fresh chicken manure. The chicken manure had a total nitrogen content of 1.2% (dry basis), a moisture content of 70%, and a strong ammonia odor. A trough fermentation system was used. After mixing, the materials entered the fermentation trough, with forced ventilation (0.3 m³ / min·m³) and turning every 3 days.

[0152] Dynamic monitoring results (detection points 0, 7, 14, 21, and 30 days): Ammonium nitrogen retention rate after 30 days: 25.4% in the control group and 83.9% in the conditioner-added group. Peak ammonia emissions: 85 ppm in the control group and 21 ppm in the conditioner-added group, a reduction rate of 75.3%. Peak hydrogen sulfide emissions: 32 ppm in the control group and 3.2 ppm in the conditioner-added group, a reduction rate of 90.0%. Compost product: After 30 days, the total nutrient content of the product was 6.5%, an increase of 23% compared to the control group (5.3%). The ammonia concentration in the workshop decreased from 15 ppm to below 5 ppm, significantly improving the working environment.

[0153] Through the detailed description of the above specific embodiments, multiple examples, comparative examples, and application examples, it is clear that the livestock and poultry manure nitrogen retention and odor synergistic compound conditioner provided by the present invention, through a four-level synergistic network of "adsorption-precipitation-inhibition-biotransformation" formed by adsorption units, acidification units, microbial inhibition units, and functional microbial agent units, can increase the ammonium nitrogen retention rate to over 85% during 30-day composting, reduce peak ammonia emissions by ≥70%, and reduce peak hydrogen sulfide emissions by ≥85%. Its effects far exceed the level of existing technologies, demonstrating high inventiveness and industrial applicability. Furthermore, its wide applicability has been verified by different types of manure (pigs, cattle, chickens), and dynamic monitoring data fully demonstrates the synergistic effect mechanism. The preparation process of the present invention is mild (maximum temperature 45℃), effectively preserving heat-sensitive components and functional microbial activity. The finished product is granular, dust-free, and has good flowability, making it suitable for automated applications in large-scale farms and organic fertilizer plants.

[0154] In summary, the nitrogen retention and odor synergistic compound conditioner for livestock and poultry manure provided by this invention, through the selection and proportioning of specific components and a mild preparation process, effectively solves the problems of severe nitrogen loss and difficulty in simultaneously controlling odorous gases in the prior art, and has significant synergistic effects and broad application prospects.

[0155] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A compound conditioner for nitrogen retention and odor synergistic effect in livestock and poultry manure, characterized in that, By weight, it includes the following components: Adsorption unit 30-60 parts, acidification unit 10-25 parts, microbial inhibition unit 5-15 parts, functional microbial agent unit 2-10 parts, skeleton filler 10-30 parts; The adsorption unit is composed of modified biochar and zeolite powder in a mass ratio of 2-4:

1. The acidification unit is composed of citric acid and ferrous sulfate in a mass ratio of 1:0.5-2; The microbial inhibition unit is composed of cinnamaldehyde and D-amino acids in a mass ratio of 1:0.3-1; The functional microbial agent unit is composed of nitrifying bacteria, denitrifying bacteria, and thiobacillus in a mass ratio of 1-3:1-2:1; The skeleton filler is bentonite.

2. The livestock and poultry manure nitrogen retention and odor synergistic compound conditioner according to claim 1, characterized in that, The modified biochar is prepared by immersing corn straw char in a phosphoric acid solution with a mass fraction of 8%-12% for 6-10 hours, removing it and then pyrolyzing it at 500-600℃ under a nitrogen atmosphere for 1-2 hours. After cooling, it is washed with water until the pH is 5.5-6.5, dried, and ground through an 80-mesh sieve.

3. The livestock and poultry manure nitrogen retention and odor synergistic compound conditioner according to claim 1, characterized in that, The zeolite powder is clinoptilolite powder with a particle size of 100-200 mesh and a specific surface area ≥300m² / g; the bentonite is sodium-based bentonite with a montmorillonite content ≥75%.

4. The livestock and poultry manure nitrogen retention and odor synergistic compound conditioner according to claim 1, characterized in that, The D-type amino acid is at least one of D-aspartic acid or D-glutamic acid, and the nitrifying bacteria, denitrifying bacteria, and thiobacillus are all heat-resistant strains that have been selectively isolated from high-temperature composting environments and can withstand composting temperatures of 55-60℃.

5. The livestock and poultry manure nitrogen retention and odor synergistic compound conditioner according to claim 1, characterized in that, The composite conditioner consists of spherical particles with a diameter of 0.5-2 mm, a moisture content of ≤5%, and an angle of repose of ≤35°.

6. The preparation method of the nitrogen retention and odor synergistic compound conditioner for livestock and poultry manure according to any one of claims 1 to 5, characterized in that, Includes the following steps: Step A: The modified biochar is prepared by soaking corn straw char in a phosphoric acid solution with a mass fraction of 8%-12% for 6-10 hours, removing it and then pyrolyzing it at 500-600℃ under a nitrogen atmosphere for 1-2 hours. After cooling, it is washed with water until the pH reaches 5.5-6.5, dried and ground through an 80-mesh sieve. Step B: Weigh citric acid and ferrous sulfate according to the ratio, add 0.8-1.2 times the total mass of the two in deionized water, stir to dissolve, and obtain an acidified mixture; Step C: Add the adsorption unit, the microbial inhibition unit, the functional microbial agent unit and the skeleton filler into the mixer and stir at 200-400 rpm for 10-15 minutes; keep the material temperature at 15-25℃, and spray the acidified mixture into the mixture while stirring, and continue stirring until wet particles are formed; Step D: Vacuum dry the wet granules at 35-45℃ until the moisture content is ≤5%, and sieve to obtain 0.5-2mm granules; wherein the vacuum drying temperature is controlled at 35-45℃ to ensure the activity of the functional microbial agent.

7. The preparation method of the nitrogen retention and odor synergistic compound conditioner for livestock and poultry manure according to claim 6, characterized in that, In step C, the nozzle pressure for atomizing and injecting is 0.2-0.4 MPa, and the injection time is 5-8 minutes.

8. The preparation method of the nitrogen retention and odor synergistic compound conditioner for livestock and poultry manure according to claim 6, characterized in that, In step D, the drying process uses a double-cone rotary vacuum dryer with a vacuum degree of -0.06 to -0.09 MPa, a rotation speed of 5-10 rpm, and a temperature of 35-45℃.

9. The application of the nitrogen retention and odor synergistic compound conditioner for livestock and poultry manure according to any one of claims 1 to 5, characterized in that, The compound conditioner is added directly to fresh livestock and poultry manure at a ratio of 2%-6% of the total manure mass, mixed evenly, and then piled up or put into the fermentation system.

10. The application of the nitrogen retention and odor synergistic compound conditioner for livestock and poultry manure according to claim 9, characterized in that, The mixing process is carried out using a horizontal double-ribbon mixer with a mixing frequency of 30-50Hz and a mixing time of 5-10 minutes. The mixed material is then composted in windrows or troughs within 4-8 hours.

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