Coal gangue composite soil conditioner and preparation method thereof

Abstract

The invention discloses a coal gangue composite soil conditioner and a preparation method thereof, and belongs to the technical field of soil improvement. The improver is prepared from the following raw materials in parts by weight: 45-50 parts of coal gangue, calcium superphosphate, chicken manure, phosphate solubilizing bacteria, nitrogen-fixing bacteria, silicate bacteria, liquid dung, bacillus subtilis bacterial liquid, organic biomass wastes, a mixture of domestic sludge and livestock and poultry manure and the like according to a specific proportion. The preparation method of the coal gangue composite soil conditioner comprises the steps of coal gangue crushing, product A preparation, auxiliary material preparation, product B preparation, staged fermentation after mixing, static aging and the like, cooperative utilization of coal gangue and various wastes is achieved, energy consumption and cost are reduced, and the prepared conditioner can effectively improve the physical and chemical properties of soil and improve the soil quality. And the organic fertilizer is suitable for regions with different raw material ratios and climates, and has a relatively high popularization value.

Description

Technical Field

[0001] This invention relates to the field of soil improvement technology, and in particular to a coal gangue composite soil conditioner and its preparation method. Background Technology

[0002] Coal gangue is a solid waste generated during coal mining and processing. Its production is enormous, accounting for approximately 15%-20% of coal production, with a current stockpile of about 7 billion tons. The large-scale stockpiling of coal gangue not only occupies vast amounts of land but also damages the local ecological environment, making it a pressing industrial solid waste problem. However, coal gangue contains elements such as silicon, aluminum, carbon, iron, sulfur, and calcium, as well as small amounts of potassium, organic matter, and trace elements beneficial to crops, giving it the potential to be used as a raw material for soil conditioners.

[0003] Currently, there are many problems in the comprehensive utilization of coal gangue, such as low utilization rate, high cost of utilization process, high energy consumption, difficult operation, and difficulty in preparing soil conditioners. Existing soil conditioners often cannot make full use of coal gangue resources to achieve low-cost and high-efficiency soil improvement effects. Therefore, developing a soil conditioner that can effectively utilize coal gangue, and has low cost and good effect, as well as its preparation method, has important practical significance. Summary of the Invention

[0004] The purpose of this invention is to provide a coal gangue composite soil conditioner and its preparation method, so as to solve the problems of low utilization rate, high utilization cost, high energy consumption, difficult operation and difficult preparation of soil conditioner in the comprehensive utilization of coal gangue mentioned in the background art. At the same time, it overcomes the defects of existing soil conditioners that cannot fully utilize coal gangue resources and are difficult to achieve low-cost and high-efficiency soil improvement effects.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a coal gangue composite soil conditioner, comprising the following raw materials by weight: 45-50 parts by weight of coal gangue, 2-3.5 parts by weight of superphosphate, 4-6 parts by weight of chicken manure, 0.008-0.012 parts by weight of functional bacteria such as phosphate-solubilizing bacteria, 0.0008-0.0012 parts by weight of nitrogen-fixing bacteria, 0.0008-0.0012 parts by weight of silicate bacteria, 7.65-12.75 parts by weight of sewage, 1-1.5 parts by weight of Bacillus subtilis bacterial solution, 20-25 parts by weight of organic biomass waste, and 15-20 parts by weight of a mixture of domestic sewage sludge and livestock and poultry manure;

[0006] A method for preparing a coal gangue composite soil conditioner includes the following steps:

[0007] Step S101: Coal gangue crushing

[0008] The coal gangue is crushed to obtain irregular coal gangue particles with a maximum particle size of no more than 600 micrometers.

[0009] Step S102: Prepare product A

[0010] The composting period is specified as 20 days, with turning the compost pile twice during this period, on the 7th and 14th days (turning depth ≥ 50cm), to ensure uniform decomposition. After composting, the moisture content of the material is tested using a drying method (50g sample dried at 105℃ to constant weight). When the moisture content drops to 35-40%, Bacillus subtilis bacterial solution (concentration 1×10⁻⁶) is sprayed on top. 8 (CFU / mL), the spraying amount is calculated as 0.5L per square meter of material surface. After spraying, let it stand for 2 hours to allow the bacterial solution to be fully adsorbed on the material surface.

[0011] Step S103: Preparation of excipients

[0012] The organic biomass waste (particle size ≤10mm after crushing) is pulverized and placed in an oxygen-supplied sealed tank for high-temperature and high-pressure treatment at 130℃ and 2 standard atmospheres (treatment time 30 minutes). After treatment, it is first mechanically dehydrated using a plate and frame filter press (pressure 0.3MPa, dehydration time 1 hour) to reduce the moisture content to 60-65%. Then, cooling water is introduced to lower the material temperature to 45℃. Finally, a broad-spectrum fertilizer fermentation agent (with an activity ≥2×10⁻⁶) is added at a mass ratio of (0.8-1.2):100 to the auxiliary materials. 8 Fermentation was carried out using CFU / g for 15 days, excluding cooling and dehydration stages. During fermentation, the temperature was maintained at 30-35℃ using a jacketed heater, and the moisture content was adjusted (maintained at 50-55%) by turning the pile once a day (turning speed 2m / min). After turning, the actinomycete activity was tested (using plate counting method) to ensure that the activity loss was controlled within 10%.

[0013] Step S104: Prepare product B

[0014] The sewage sludge, livestock and poultry manure and the auxiliary materials obtained in step S103 are mixed at a mass ratio of 3-5:1 and aerobic fermentation is carried out. The fermentation cycle is 20 days. During this period, the pile is turned over once a day and the pile temperature is maintained at 55-60℃ for high-temperature sterilization.

[0015] After fermentation, cooling water is introduced to lower the temperature to below 35°C, yielding product B.

[0016] Step S105: Preparation of soil conditioner

[0017] Static aging

[0018] After fermentation, the material is transferred to an aging warehouse for 30-45 days of natural storage.

[0019] During this period, the following operations must be strictly performed:

[0020] Daily Monitoring and Control: Monitor the moisture content of the materials daily to ensure it remains between 30-35%. When the moisture content falls below 30%, replenish the moisture by spraying water onto the surface using atomizing nozzles to avoid localized water accumulation. Simultaneously, use a portable methane detector (measurement range 0-100% LEL) to monitor the concentration of combustible gas in real time. Since the lower explosive limit (LEL) of methane is 5% by volume, when the detected methane concentration reaches 3% (i.e., 60% LEL), immediately activate the dual-fan system (total air volume 20,000 m³ / h) at the bottom and top of the silo for forced ventilation. During ventilation, check the methane concentration every 30 minutes until it drops below 1% (i.e., 20% LEL) before stopping ventilation. After ventilation, check again to confirm that the concentration is stable.

[0021] Turning operation specifications: One hour before turning, the methane concentration should be checked again. Only when the concentration is confirmed to be ≤1% can the explosion-proof turning machine (equipped with an explosion-proof motor and static elimination device) be used for turning. During the turning process, continuous ventilation by dual fans must be maintained. The turning path should be from the edge of the silo to the center to avoid violent turning of the material causing a sudden release of methane.

[0022] Turnover triggering mechanism: Turnover is mainly triggered when the core temperature is ≥45℃ (core temperature is measured by an insertion thermocouple sensor 30cm below the center of the reactor). If the core temperature does not exceed 45℃, turnover is performed once on day 15 and once on day 30. After turnover, the temperature change curve of the reactor body needs to be recorded to provide a basis for subsequent batch parameter optimization.

[0023] Segmented fermentation control

[0024] For the first 30 days: A system combining stratified aeration and pulse ventilation was used. Spiral air distribution pipes (8mm aperture, 50cm spacing) were installed at the bottom and middle of the fermentation chamber. The air distribution pipes were installed at a 15° angle to the horizontal plane to improve the efficiency of oxygen diffusion to deeper layers. The oxygenation parameters were adjusted to 0.3m³ / min·m³ of material, and the oxygenation time was extended to 60 minutes. A pulse ventilation mode was adopted, with a 2-minute pause every 10 minutes of ventilation. Actual measurements showed that the dissolved oxygen levels in each layer after oxygenation were as follows: 4-5mg / L at the surface layer (30cm), 1-2mg / L at the middle layer (50cm), and 0.1-0.3mg / L at the deepest layer (1m). These data were measured by an embedded dissolved oxygen sensor and are consistent with the diffusion law of oxygen in highly porous materials.

[0025] For the next 30 days: the oxygenation parameters were adjusted to 0.2 m³ / min·m³ of material, with an oxygenation time of 45 minutes, and pulse ventilation was also used. During this stage, the dissolved oxygen at a depth of 1 m was controlled at 0.05-0.1 mg / L. By reducing the ventilation volume and shortening the ventilation time, an anaerobic environment suitable for mineralization was created, and the dissolved oxygen change curve was recorded daily to verify the environmental stability.

[0026] Environmental control measures

[0027] Temperature control: A serpentine cooling water pipe system (50mm diameter, 30cm spacing) is installed on the inner wall of the fermentation chamber. When the core temperature exceeds 35℃, the circulating cooling water system automatically activates (inlet water temperature ≤25℃, flow rate automatically adjusted according to temperature difference). This is achieved through linkage control via temperature sensors (accuracy ±0.5℃) to ensure that mesophilic bacteria (optimal 25-35℃) are in a suitable activity environment. The temperature difference between the inlet and outlet of the cooling water pipes must be controlled within 5℃ to avoid excessively rapid local cooling that could cause fluctuations in microbial activity.

[0028] Moisture content control: When the moisture content of the material is >35%, reduce the ventilation time by 10 minutes and reduce the turning frequency to once every 3 days. Use a low-speed stirring mode when turning to reduce moisture evaporation. When the moisture content is <30%, use spray atomized water to supplement the moisture. The amount added each time should be ≤3% of the total mass of the material. After spraying water, let it stand for 2 hours and then test the moisture content to avoid local over-wetting.

[0029] Reaction mechanism

[0030] The first 30 days (humification stage): After 60 minutes of oxygenation, the surface and middle layers of material are in a high-oxygen environment. The metabolic activity of aerobic microorganisms (such as Bacillus and Actinomycetes) is enhanced. They decompose macromolecular organic matter such as cellulose and lignin by secreting extracellular enzymes, generating humic acid precursors (such as phenols and amino acids). As oxygen is continuously consumed, the dissolved oxygen in the surface layer drops below 1 mg / L after 4-6 hours, entering a facultative anaerobic state (dominated by facultative bacteria such as yeast and lactic acid bacteria). After 8-10 hours, the dissolved oxygen in the middle layer drops below 0.5 mg / L, also entering a facultative anaerobic state. Meanwhile, the deep layers, due to oxygen diffusion limitations, remain in a low-oxygen environment (dissolved oxygen ≤ 0.3 mg / L), with microorganisms primarily metabolizing anaerobic bacteria such as Clostridium. This process, by extending the oxygenation time and using a pulsed mode, expands the aerobic zone by 20-30% compared to traditional processes, increasing humic acid production.

[0031] In the last 30 days (mineralization stage): the shortened aeration time leads to a decrease in the overall oxygen content of the material. The dissolved oxygen in the surface material drops below 0.5 mg / L within 2-3 hours after aeration ends, entering a facultative anaerobic state. The middle and deep layers, due to their low initial oxygen content, quickly enter an anaerobic state (dissolved oxygen ≤ 0.1 mg / L). At this time, methanogenic bacteria (such as *Methanococcus methanans*) and sulfate-reducing bacteria become the dominant microbial population. Through anaerobic respiration, they further decompose small-molecule organic matter (such as organic acids and alcohols) into methane, carbon dioxide, and readily available nutrients such as inorganic nitrogen and phosphorus. The mineralization rate is increased by 40-50% compared to the entire aerobic process, meeting the crop's demand for readily available nutrients.

[0032] Compared with the prior art, the beneficial effects of the present invention are:

[0033] This coal gangue composite soil conditioner, when applied to the soil, can reduce soil bulk density, increase total soil porosity, and enhance soil cation exchange capacity, thereby improving the drought resistance of crops. Simultaneously, it improves soil transparency and fertilizer retention and supply properties, promoting crop growth and development and increasing crop yield. The organic matter in the conditioner, after being applied to the soil, is decomposed and transformed by microorganisms to resynthesize complex organic colloids containing soluble proteins and humic acid. It has moderate binding properties, loosening clay soils and binding sandy soils into granular structures. Containing various nutrients, it is beneficial to microbial activity and plant growth, possessing the fertilizing effects of both organic and inorganic fertilizers, making it an excellent soil conditioner. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the composition of the coal gangue composite soil conditioner of the present invention;

[0035] Figure 2 This is a schematic diagram of the preparation method of the coal gangue composite soil conditioner of the present invention. Detailed Implementation

[0036] Example 1

[0037] Raw material preparation: Prepare raw materials according to the following mass percentages: coal gangue 48%, superphosphate 5%, chicken manure 10%, phosphate-solubilizing bacteria 0.001%, nitrogen-fixing bacteria 0.001%, silicate bacteria 0.001%, sewage 10%, Bacillus subtilis bacterial solution 1.2%, organic biomass waste 22%, and a mixture of domestic sewage sludge and livestock manure 18%. The coal gangue is crushed to a maximum particle size of 500 micrometers, and the Bacillus subtilis bacterial solution concentration is 1×10⁻⁶. 8 The activity of the broad-spectrum fertilizer fermentation inoculant was 2.5 × 10 CFU / mL. 8 CFU / g.

[0038] Preparation process:

[0039] Step S101: Crush the coal gangue to the above-mentioned particle size.

[0040] Step S102: Mix the crushed coal gangue with superphosphate and chicken manure, add manure water, and compost for 20 days. Turn the pile twice, on the 7th and 14th days, to a depth of 55cm. After composting, check the moisture content; it should be 38%. Spray with Bacillus subtilis solution to obtain product A.

[0041] Step S103: Crush the organic biomass waste to a particle size of 8mm, treat it at 130℃ and 2 standard atmospheres for 30 minutes, mechanically dehydrate it to a moisture content of 62%, cool it down to 45℃, add a broad-spectrum fertilizer fermentation agent with a mass ratio of 1:100 to the auxiliary material, ferment it at 32℃ for 15 days, turn it over once a day, and maintain a moisture content of 52% to obtain the auxiliary material.

[0042] Step S104: Mix domestic sewage sludge, livestock and poultry manure and the auxiliary materials obtained in step S103 at a mass ratio of 4:1, and aerobic ferment at 58℃ for 20 days, turning the pile once a day. After fermentation, cool down to 32℃ to obtain product B.

[0043] Step S105: Mix product A and product B at a mass ratio of 4:6, and carry out segmented fermentation and static aging. During the segmented fermentation, the oxygenation parameter for the first 30 days is 0.3 m³ / min·m³ of material, with oxygenation for 60 minutes, using a pulse ventilation mode of 10 minutes of ventilation followed by 2 minutes of pausing; for the next 30 days, the oxygenation parameter is 0.2 m³ / min·m³ of material, with oxygenation for 45 minutes, using the same pulse ventilation mode. The static aging time is 40 days, during which the moisture content is maintained at 32%. When the methane concentration reaches 3%, the dual-fan system with a total air volume of 20,000 m³ / h is turned for ventilation. When the core temperature reaches 46℃, the pile is turned over. At other times, the pile is turned over once on the 15th day and once on the 30th day to obtain the coal gangue composite soil conditioner.

[0044] Effect test: After the soil conditioner was applied to infertile soil, the soil bulk density decreased by 18%, the total porosity increased by 23%, the available phosphorus content increased by 35%, the available nitrogen content increased by 23%, and the wheat yield per mu increased by 13%.

[0045] Example 2

[0046] Raw material preparation: 45% coal gangue, 3% superphosphate, 8% chicken manure, 0.0008% phosphate-solubilizing bacteria, 0.0008% nitrogen-fixing bacteria, 0.0008% silicate bacteria, 8% manure, 1% Bacillus subtilis bacterial solution, 25% organic biomass waste, and 15% mixture of domestic sewage sludge and livestock manure. The coal gangue is crushed to a maximum particle size of 600 micrometers, and the Bacillus subtilis bacterial solution concentration is 1×10⁻⁶. 8CFU / mL, the activity of the broad-spectrum fertilizer fermentation inoculant is 2×10⁻⁶. 8 CFU / g.

[0047] Preparation process:

[0048] Step S101: Crush the coal gangue to the above-mentioned particle size.

[0049] Step S102: Compost for 20 days, turn the compost pile on the 7th and 14th days, turning it to a depth of 50cm. After composting, the moisture content should be 35%. Spray with bacterial solution to obtain product A.

[0050] Step S103: Crush organic biomass waste to 10mm, dehydrate to 65% after high temperature and high pressure treatment, add bacterial agent after cooling and ferment at 30℃ for 15 days, turn the pile daily, and obtain auxiliary material with 50% moisture content.

[0051] Step S104: Mix domestic sewage sludge, livestock and poultry manure and auxiliary materials in a 3:1 ratio, ferment at 55℃ for 20 days, and then cool down to 30℃ to obtain product B.

[0052] Step S105: Mix product A and product B in a 4:5 ratio, and perform the same staged fermentation as in Example 1. Static age for 30 days, during which the moisture content is controlled at 30%. Ventilate when the methane concentration reaches 3%, and turn the pile when the core temperature exceeds 45°C to obtain the improver.

[0053] Results showed that soil bulk density decreased by 15%, total porosity increased by 20%, available phosphorus increased by 30%, available nitrogen increased by 20%, and corn yield per mu increased by 10%.

[0054] Example 3 (Adapted with high proportion of coal gangue)

[0055] Raw material preparation: 50% coal gangue, 7% superphosphate, 12% chicken manure, 0.0012% phosphate-solubilizing bacteria, 0.0012% nitrogen-fixing bacteria, 0.0012% silicate bacteria, 12.75% sewage, 1.5% Bacillus subtilis bacterial solution, 12% organic biomass waste, and 4.7454% mixture of domestic sewage sludge and livestock manure. The coal gangue is crushed to a maximum particle size of 550 micrometers, and the Bacillus subtilis bacterial solution concentration is 1×10⁻⁶. 8 CFU / mL, broad-spectrum fertilizer fermentation inoculant activity 2.8×10 8 CFU / g.

[0056] Preparation process:

[0057] Steps S101-S104 are the same as in Example 1, except that the mixing ratio of product A and product B is adjusted to 4:5.5.

[0058] The fermentation parameters for step S105 remain unchanged, and the plant is statically aged for 35 days. During this period, the pile is turned once when the core temperature reaches a maximum of 47℃, and the pile is turned according to the cycle for the rest of the time.

[0059] Effect test: After application to sandy soil, the soil water retention capacity increased by 25%, the aggregate structure formation rate increased by 30% compared with the control group, and the peanut yield per mu increased by 14%. Although the proportion of coal gangue increased, the improvement effect was still maintained through functional microbial agents and fermentation parameter optimization, proving the suitability of the scheme for high proportion of coal gangue.

[0060] Example 4 (Application in cold northern regions)

[0061] Raw material preparation: 46% coal gangue, 4% superphosphate, 10% chicken manure, 0.001% phosphate-solubilizing bacteria, 0.001% nitrogen-fixing bacteria, 0.001% silicate bacteria, 9% sewage, 1.2% Bacillus subtilis bacterial solution, 23% organic biomass waste, and 16.797% mixture of domestic sludge and livestock and poultry manure.

[0062] Preparation process:

[0063] In step S105, the oxygenation time is extended to 70 minutes for the first 30 days (due to reduced oxygen diffusion efficiency in low-temperature environments), and to 50 minutes for the next 30 days. During the static aging period, an insulated shed is used to maintain the temperature inside the warehouse at ≥15℃.

[0064] Effect test: When applied to black calcareous soil in Northeast China, before the soil freezes in winter and tested after the soil thaws in the following spring, the soil cation exchange capacity increased by 18% and the survival rate of corn seedlings increased by 20%. The effect is significantly better than the traditional process in low-temperature areas (the traditional process only improves the same indicators by 8-10%).

[0065] Comparison Column 1 (Traditional Craftsmanship)

[0066] Raw materials and preparation: The same types and proportions of raw materials as in Example 1 were used, but the preparation method was traditional full-process aerobic fermentation, with oxygenation for 30 minutes every 24 hours at a rate of 0.6 m³ / min・m³, without segmented fermentation and precise static aging control.

[0067] Effect test: After the soil conditioner was applied, the soil bulk density decreased by 10%, the total porosity increased by 12%, the available phosphorus content increased by 18%, the available nitrogen content increased by 12%, and the wheat yield per mu increased by 5%. Compared with Example 1, all indicators showed significant differences, and the energy consumption per unit material was 8.2 kWh / ton, and the organic matter conversion rate was 42%.

[0068] Comparison Column 2 (Non-functional bacterial agent)

[0069] Raw materials and preparation: Phosphate-solubilizing bacteria, nitrogen-fixing bacteria and silicate bacteria were removed from the raw materials, and the remaining raw materials and preparation process were the same as in Example 1.

[0070] Effect test: The available phosphorus content in the soil increased by only 10%, the available nitrogen content increased by 8%, and the crop yield per mu increased by 4%, which was significantly lower than that in Example 1, indicating that the functional microbial agent plays an important role in nutrient conversion and crop yield increase.

[0071] Compare with Column 3 (traditional process with high proportion of coal gangue)

[0072] Raw materials and preparation: The same raw material ratio as in Example 3 (50% coal gangue) was used, but the preparation process adopted traditional full-process aerobic fermentation (oxygenation for 30 minutes every 24 hours, aeration rate of 0.6 m³ / min・m³), without segmented fermentation parameter optimization, and static aging was only carried out by turning the pile on a fixed date.

[0073] Effect test: After application to sandy soil, due to the excessively high proportion of coal gangue and insufficient fermentation, the soil water retention capacity only increased by 8%, the aggregate formation rate increased by 12% compared to the control group, and the peanut yield per mu increased by only 5%. Compared with Example 3, the improvement effect was significantly different, and due to the insufficient decomposition of coal gangue, some soils showed compaction.

[0074] Comparison Column 4 (No special control measures are implemented in cold northern regions)

[0075] Raw materials and preparation: The same raw material ratio as in Example 4 was used. The oxygenation time was not extended during the preparation process, and no heat preservation measures were taken during the static aging period (the temperature inside the chamber varied with the environment, reaching as low as -5℃).

[0076] Effect test: After application in black calcareous soil in Northeast China, the test in the following spring showed that the soil cation exchange capacity increased by only 7% and the survival rate of corn seedlings increased by 6%, which was far lower than the indicators of Example 4. Moreover, due to the low temperature, some functional bacteria were inactivated, and the effective period of the amendment was shortened to 1 year (the effective period of Example 4 was 2 years).

[0077] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A coal gangue composite soil conditioner, characterized in that, The raw materials are composed of the following by weight: 45-50 parts coal gangue, 2-3.5 parts superphosphate, 4-6 parts chicken manure, 0.008-0.012 parts functional bacteria such as phosphate-solubilizing bacteria, 0.0008-0.0012 parts nitrogen-fixing bacteria, 0.0008-0.0012 parts silicate bacteria, 7.65-12.75 parts sewage, 1-1.5 parts Bacillus subtilis bacterial solution, 20-25 parts organic biomass waste, and 15-20 parts a mixture of domestic sewage sludge and livestock and poultry manure. The maximum particle size of the crushed coal gangue is no more than 600 micrometers, and the concentration of the Bacillus subtilis bacterial solution is 1×10⁻⁶. 8 CFU / mL; the organic biomass waste is at least one of straw, distiller's grains, vinegar residue, and mushroom residue.

2. The coal gangue composite soil conditioner according to claim 1, characterized in that, The mass ratio of the auxiliary material obtained after processing the mixture of domestic sewage sludge, livestock and poultry manure, and organic biomass waste is 3-5:

1.

3. A method for preparing a coal gangue composite soil conditioner as described in any one of claims 1-2, characterized in that, Includes the following steps: S101: Crush coal gangue to a maximum particle size not exceeding 600 micrometers; S102: Mix crushed coal gangue with superphosphate and chicken manure, add manure water and compost for 20 days. Turn the pile once on the 7th and 14th days during the period, and turn the pile to a depth of ≥50cm. After composting, test the moisture content of the material. When the moisture content drops to 35-40%, spray with Bacillus subtilis bacterial solution to obtain product A. S103: Crush organic biomass waste to a particle size ≤10mm, treat it at 130℃ and 2 standard atmospheres for 30 minutes, mechanically dehydrate it to a moisture content of 60-65%, cool it to 45℃, add a broad-spectrum fertilizer fermentation agent with a mass ratio of 0.8-1.2:100 to the auxiliary material, ferment it at 30-35℃ for 15 days, turn it over once a day, and maintain a moisture content of 50-55% to obtain the auxiliary material; S104: Mix domestic sewage sludge, livestock and poultry manure and the auxiliary materials obtained in step S103 at a mass ratio of 3-5:1, and aerobic ferment at 55-60℃ for 20 days, turning the pile once a day. After fermentation, cool down to below 35℃ to obtain product B. S105: Mix product A and product B at a mass ratio of 4:5-7, and carry out segmented fermentation and static aging to obtain a coal gangue composite soil conditioner. In the segmented fermentation, the oxygenation parameter for the first 30 days is 0.3 m³ / min·m³ of material, with oxygenation for 60 minutes, using a pulse ventilation mode of stopping for 2 minutes every 10 minutes of ventilation. In the next 30 days, the oxygenation parameter is 0.2 m³ / min·m³ of material, with oxygenation for 45 minutes, using the same pulse ventilation mode. The static aging time is 30-45 days, during which the moisture content is maintained at 30-35%. When the methane concentration reaches 3%, the dual-fan system with a total air volume of 20,000 m³ / h is turned for ventilation. When the core temperature is ≥45℃, the pile is turned over. If the temperature does not exceed the standard, the pile is turned over once on the 15th day and once on the 30th day.

4. The preparation method according to claim 3, characterized in that, The broad-spectrum fertilizer fermentation inoculant activity described in step S103 is ≥2×10⁻⁶. 8 CFU / g.

5. The preparation method according to claim 3, characterized in that, In step S105, during the segmented fermentation, spiral gas distribution pipes are installed at the bottom and middle of the fermentation chamber. The gas distribution pipes have an 8mm diameter hole, a spacing of 50cm, and are installed at a 15° angle to the horizontal plane.

6. The preparation method according to claim 3, characterized in that, During static aging in step S105, an explosion-proof turning machine is used for turning the pile. The methane concentration is tested 1 hour before turning the pile, and the operation can only be carried out after confirming that it is ≤1%. During the turning process, dual fans are kept for continuous ventilation.

7. The preparation method according to claim 3, characterized in that, Step S105 also includes environmental control measures: when the core temperature exceeds 35°C, circulating cooling water is introduced through a serpentine cooling water pipe; when the moisture content is >35%, the ventilation time is reduced by 10 minutes and the turning frequency is reduced to once every 3 days; when the moisture content is <30%, atomized water is sprayed, with the amount added each time ≤3% of the total mass of the material.

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