Asphalt mixing station recycling powder garden greening nutrient soil and preparation method thereof

Abstract

The present application belongs to the technical field of industrial waste agricultural and forestry resource utilization, and particularly relates to a kind of asphalt mixing station recycled powder landscaping nutrient soil and a preparation method thereof.The asphalt mixing station recycled powder landscaping nutrient soil according to the present application is composed of the following raw materials in parts by weight: recycled powder 50-75 parts, biological organic fertilizer 20-45 parts, matured cow dung 3-25 parts, mushroom dregs 2-10 parts, furfural residue 1-5 parts, vermiculite 2-15 parts, landscaping nursery stock formula fertilizer 0.2-0.5 parts, and water-retaining agent 1-5 parts.The asphalt mixing station recycled powder landscaping nutrient soil according to the present application solves the technical problem of limited consumption capacity of industrial resource utilization of asphalt mixing station recycled powder, innovates the agricultural and forestry resource utilization technical method of preparing landscaping nutrient soil with asphalt mixing station recycled powder as the main component, and improves the digestion and disposal capacity of asphalt mixing station recycled powder.

Description

Technical Field

[0001] This invention belongs to the field of industrial waste agricultural and forestry resource utilization technology, specifically relating to a nutrient soil for landscaping made from recycled powder from asphalt mixing plants and its preparation method. Background Technology

[0002] Asphalt mixing plant recycled dust refers to the waste stone powder collected during the production of asphalt mixtures required for road paving. Road paving asphalt mixtures are made by mixing asphalt, aggregates, fillers, and other materials in a specific ratio. The aggregates are obtained by crushing quarry stones into gravel of a certain size. During the crushing process, various waste powder particles of different sizes inevitably adhere to the surface of the gravel, most of which are smaller than 0.075 mm. The presence of these waste powder particles directly affects the adhesion, uniformity, and curing strength of the asphalt mixture, and inevitably impacts the quality of road paving. Therefore, these aggregate powder particles must be cleaned or removed. Currently, asphalt mixing plants employ various dust removal and emission methods, among which the baghouse dust collector wet emission mode, which improves the quality of the working environment, is relatively widely used. This method involves conveying the aggregate (also known as the asphalt mixing stone) required by the asphalt mixing plant to a heating drum in the required proportions. The temperature reaches approximately 180℃. During heating, the aggregate is scattered through the drum, and under the combined action of a blower and an induced draft fan, the powder adhering to the surface of the aggregate is collected and recycled using a bag filter. The recycled powder is then mixed with water by a forced mixer and centrally discharged. The aggregate waste powder collected, recycled, and centrally discharged during the aggregate cleaning process at the asphalt mixing plant is called recycled powder.

[0003] According to statistics from the Ministry of Transport, the total length of highways in my country reached 5.4368 million kilometers by the end of 2023, ranking first in the world. From 2019 to 2023, an average of 106,100 kilometers were added annually. This demonstrates that with the rapid development of the national economy, the demand for highway construction is increasing, leading to a greater demand for asphalt mixture aggregates and consequently, a significant increase in the amount of recycled powder. Statistics show that approximately 50 kg of recycled powder is generated for every ton of asphalt mixture produced, representing a generation rate of about 5%. Although highways vary in grade and number of lanes, a rough estimate suggests that paving an asphalt pavement requires approximately 960 tons of asphalt mixture per kilometer, which translates to about 48 tons of recycled powder per kilometer. Therefore, by the end of 2023, approximately 260 million tons of recycled powder had been generated, not to mention the approximately 5.0928 million tons of new recycled powder generated annually. Thus, the amount of recycled powder generated is enormous.

[0004] The main chemical components of the recycled powder are SiO2, CaCO3, CaO, and silicates, with an average bulk density of 1.15 g / cm³. 3Asphalt powder from asphalt mixing plants contains over 80% particles with a diameter ≤0.075 mm (200 mesh), exhibiting characteristics such as small particle size, high mud content, small specific surface area, low plasticity, weak cohesion, and poor water stability. The reuse of asphalt powder from mixing plants is primarily as a raw material for preparing mineral fillers, concrete materials, and road base materials for industrial applications. However, due to its complex composition, small particle size, high mud content, and difficulty in solidification, the proportion of recycled powder added in many reuse technologies is less than 25%, mostly around 5%, which is a low percentage, limiting its application and significantly restricting its utilization capacity. Furthermore, there are issues such as immature industrial reuse technologies, numerous formulation components, high processing costs, poor mixture performance, and various secondary problems or hidden dangers after application, including microscopic cracks. Meanwhile, there are currently no reports on the agricultural and forestry resource utilization of asphalt powder from mixing plants. Therefore, the improved utilization of asphalt powder from mixing plants is a pressing production problem that road and bridge construction companies need to solve, and a key technological bottleneck for achieving high-quality development.

[0005] Although recycled asphalt mixing plant powder is not strictly speaking soil, it can be considered parent material for soil formation and already possesses primary fertility. Meanwhile, the main chemical properties of the recycled powder are high pH (8.53–11.75), low organic matter content (0.27–0.83 g / kg), and low levels of available nitrogen and phosphorus nutrients, with only abundant available potassium. However, the levels of pollutants such as cadmium, mercury, arsenic, lead, chromium, copper, as well as DDT, DDT, and benzo[a]pyrene are all far below the levels specified in GB 15618-2018. The soil pollution risk screening value in the "Soil Environmental Quality Agricultural Land Soil Pollution Risk Control Standard (Trial)" indicates a low pollution risk that can generally be ignored. Therefore, asphalt mixing plant recycled powder can be completely improved into nutrient soil for landscaping and agricultural and forestry resource utilization. This not only realizes the agricultural and forestry resource utilization of industrial waste, reduces the occupation of land resources, and lowers the risks of environmental pollution and harm to human health, but also further solves the large demand for urban landscaping substrate nutrient soil due to rapid urbanization. It turns waste into treasure, significantly increases economic, social and ecological benefits, and truly promotes the ecological cycle and green, efficient and sustainable development of industry and agriculture. Summary of the Invention

[0006] The purpose of this invention is to provide a nutrient soil for landscaping made from recycled asphalt mixing plant powder, which realizes the agricultural and forestry resource utilization of recycled asphalt mixing plant powder; this invention also provides its preparation method.

[0007] The garden greening nutrient soil made from recycled powder from asphalt mixing plants described in this invention is composed of the following raw materials by weight: 50-75 parts recycled powder, 20-45 parts bio-organic fertilizer, 3-25 parts decomposed cow manure, 2-10 parts mushroom residue, 1-5 parts furfural residue, 2-15 parts vermiculite, 0.2-0.5 parts greening seedling formula fertilizer, and 1-5 parts water-retaining agent.

[0008] in:

[0009] The recycled powder is waste powder collected and recycled by asphalt mixing plants, with a particle size ≤2mm and a moisture content ≤5%.

[0010] The bio-organic fertilizer is a fertilizer that meets the standard of "NY 884-2012 Bio-organic Fertilizer"; its purpose is to increase the organic matter content of the recycled powder and improve its biological properties, stimulate the activity of beneficial microorganisms, and enhance biological fertility.

[0011] The decomposed cow manure is fermented and decomposed cow manure that meets the standards of "NY / T 525-2021 Organic Fertilizer"; the purpose is not only to increase the organic matter in the recycled powder, but also mainly to improve the structure of the recycled powder with the fiber of the decomposed cow manure and promote the development of the recycled powder structure.

[0012] The mushroom residue is an organic material obtained by sterilizing, disinfecting, and crushing the discarded mushroom sticks after mushroom harvesting. The particle size is ≤2mm and the moisture content is ≤3%. The main purpose of using mushroom residue is to improve the physical properties of the recycled powder, such as porosity, air permeability, and water permeability, while increasing carbon content.

[0013] The furfural residue is the waste left over from the production of furfural from corn cobs. It is rich in cellulose, lignin and a small amount of sulfuric acid, with a pH of about 2. Adding furfural residue can increase the organic matter in the recovered powder and reduce its acidity and alkalinity, thus regulating its chemical properties.

[0014] The vermiculite is a 2:1 type expansive layered aluminosilicate clay mineral with good permeability and strong water and fertilizer retention capacity. It is a commonly used soil conditioner and is often used as a substrate material for garden flowers. The particle size is ≤1mm. The purpose of adding vermiculite is to adjust the porosity and water and fertilizer retention performance of the recycled powder and improve its physical fertility.

[0015] The aforementioned greening seedling formula fertilizer is a fertilizer containing nutrients and conforming to the standard of "GB / T 21633-2020 Blended Fertilizers (BB Fertilizer)" formulated according to the nutrient requirements of greening seedlings. The blended nutrient fertilizers are mainly one or more of the conventional physiologically acidic or physiologically neutral fertilizers, wherein the ratio of slow-release nitrogen to fast-release nitrogen is ≥50%:50%. The main purpose of using greening seedling formula fertilizer is to improve the recovery of powdered nutrients, balance nutrition, regulate slow-release nutrients, and enhance chemical fertility.

[0016] Preferably, the formulated fertilizer for greening seedlings is either ryegrass formulated fertilizer or cypress seedling formulated fertilizer.

[0017] The water-retaining agent is a soil conditioner that conforms to the standard "NY / T 886-2022 Agricultural and Forestry Water-Retaining Agent" and is used to regulate water retention. Its main purpose is to improve the water and fertilizer retention of the recycled powder and improve its structure.

[0018] Preferably, the water-retaining agent is one of polyacrylamide, starch-polyacrylamide, carboxymethyl cellulose, or polyacrylonitrile.

[0019] The method for preparing garden nutrient soil using recycled powder from asphalt mixing plants, as described in this invention, comprises the following steps:

[0020] (1) First, based on the fertilizer requirements of garden greening seedlings and the requirements for the ratio of slow-release and fast-release nitrogen, select macro-, medium and micronutrient fertilizer raw materials to prepare the required greening seedling formula fertilizer;

[0021] (2) After removing impurities by passing the recycled powder through a 2 mm sieve, weigh the required amount and add the recycled powder to the mixing mixer. At the same time, calculate the amount of other added materials according to the amount of recycled powder and the required addition ratio, and weigh them for later use.

[0022] (3) Sprinkle clean water into the mixing mixer with the added recycled powder to increase the moisture content of the recycled powder to 10% to 15% and stir for 3 to 5 minutes to moisten it evenly; first, evenly sprinkle the weighed furfural residue into the mixing mixer, and then start the mixing mixer to stir for 5 to 10 minutes to mix the furfural residue and the recycled powder evenly.

[0023] (4) After the furfural residue and recycled powder are mixed evenly in step (3), they are evenly sprinkled into the continuous mixing mixer in the following order: green seedling formula fertilizer and water-retaining agent, mushroom residue and vermiculite, biological organic fertilizer and decomposed cow manure. Each group of added materials is added in sequence after the previous group of added materials and the aforementioned recycled powder mixture are mixed evenly. The mixer is stopped when all the mixtures are evenly mixed, and the recycled powder garden greening nutrient soil of the asphalt mixing plant is prepared.

[0024] Compared with the prior art, the advantages and beneficial effects of the present invention are:

[0025] (1) The garden greening nutrient soil made from recycled asphalt mixing plant powder described in this invention solves the technical problem of limited industrial resource utilization capacity of recycled asphalt mixing plant powder, innovates the agricultural and forestry resource utilization technology and method for preparing garden greening nutrient soil with recycled asphalt mixing plant powder as the main component, and improves the digestion and disposal capacity of recycled asphalt mixing plant powder.

[0026] (2) The landscaping nutrient soil made from recycled asphalt mixing plant powder described in this invention is a low-carbon, green, ecologically circular, high-quality, and efficient method for improving and utilizing recycled asphalt mixing plant powder. This method not only saves on the disposal costs of recycled powder waste but also achieves significant economic, social, and ecological benefits. The bio-organic fertilizer, decomposed cow manure, mushroom bran, furfural residue, etc., in the improved materials of this technology are reuse products of organic waste or their reuse, thus also having the characteristic of treating waste with waste.

[0027] (3) The method for preparing garden greening nutrient soil by asphalt mixing plant recycled powder described in this invention has the characteristics of simple process, simple operation and easy promotion. Its application in asphalt mixing plants can solve the technical problem of difficult disposal of asphalt mixing plant recycled powder and further promote the high-quality and rapid development of road and bridge construction enterprises. Detailed Implementation

[0028] The present invention will be further described below with reference to embodiments.

[0029] Example 1

[0030] Landscaping seedlings: Ryegrass

[0031] The asphalt mixing plant recycled powder landscaping nutrient soil described in Example 1 is composed of the following raw materials by weight: 60 parts recycled powder, 21.8 parts bio-organic fertilizer, 5 parts decomposed cow manure, 3 parts mushroom bran, 2 parts furfural residue, 6 parts vermiculite, 0.2 parts greening seedling formula fertilizer, and 2 parts water-retaining agent.

[0032] in:

[0033] The recycled powder is waste powder collected and recycled from asphalt mixing plants, with a particle size ≤2mm and a moisture content of 3.5%, and is taken from Shandong Ludong Road and Bridge Co., Ltd.

[0034] The bio-organic fertilizer is a commercially available organic fertilizer product that meets the standard of "NY 884-2012 Bio-organic Fertilizer". It was purchased from Shandong Lianyou Biotechnology Co., Ltd., with an organic matter content of ≥30% and total nutrients (N+P2O5+K2O) of ≥4%. The purpose is to increase the organic matter content of the recycled powder and improve its biological properties, stimulate the activity of beneficial microorganisms, and enhance biological fertility.

[0035] The decomposed cow manure is commercially available fermented and decomposed cow manure that meets the standard of "NY / T 525-2021 Organic Fertilizer" and was purchased from Shandong Lianyou Biotechnology Co., Ltd.; the purpose is not only to increase the organic matter in the recycled powder, but also mainly to improve the structure of the recycled powder with the fiber of the decomposed cow manure and promote the development of the recycled powder structure.

[0036] The mushroom residue is an organic material obtained by sterilizing, disinfecting, and crushing the discarded mushroom logs after mushroom harvesting. The particle size is ≤2mm and the moisture content is 2.5%. It was purchased from Shandong Lianyou Biotechnology Co., Ltd. The mushroom residue is mainly used to increase carbon content and improve the physical properties of the recycled powder, such as porosity, air permeability, and water permeability.

[0037] The furfural residue is a waste product left over from the production of furfural from corn cobs. It is rich in cellulose, lignin and a small amount of sulfuric acid, with a pH of 2, and was purchased from Shandong Lianyou Biotechnology Co., Ltd. Adding furfural residue can increase the organic matter in the recovered powder, reduce the acidity and alkalinity of the recovered powder, and regulate its chemical properties.

[0038] The vermiculite is a 2:1 type expansive layered aluminosilicate clay mineral with good permeability and strong water and fertilizer retention capacity. It is a commonly used soil conditioner and is often used as a substrate material for garden flowers. The particle size is ≤1mm and it is purchased from the local flower market. The purpose of adding vermiculite is to adjust the porosity and water and fertilizer retention performance of the recycled powder and improve its physical fertility.

[0039] The aforementioned greening seedling formula fertilizer is a fertilizer containing nutrient elements and conforming to the standard of "GB / T 21633-2020 Blended Fertilizers (BB Fertilizer)" formulated according to the nutrient requirements of greening seedlings. It uses nutrient element fertilizers purchased from the local agricultural input market. Its raw materials are: urea, ammonium sulfate, monoammonium phosphate, diammonium phosphate, superphosphate, triple superphosphate, potassium sulfate, calcium sulfate, magnesium sulfate, ferrous sulfate, manganese sulfate, zinc sulfate, borax, and coated slow-release urea (release period of 3 months, N 42%), which are blended together. The ratio of slow-release nitrogen to fast-release nitrogen is 50%:50% to improve the recovery of powdered nutrients, balance its nutrition, regulate its slow-release and fast-release nutrient ratio, and enhance its chemical fertility.

[0040] The fertilizer for greening seedlings is ryegrass fertilizer.

[0041] The water-retaining agent is a soil conditioner that conforms to the standard "NY / T 886-2022 Agricultural and Forestry Water-Retaining Agent" and regulates water retention. Polyacrylamide is selected. Its main purpose is to improve the water and fertilizer retention of the recycled powder and improve its structure.

[0042] The method for preparing nutrient soil for landscaping using recycled powder from asphalt mixing plants, as described in Example 1, comprises the following steps:

[0043] (1) First, according to the fertilizer requirement of ryegrass, the N-P2O5-K2O ratio is 16-8-10 and the ratio of slow-release nitrogen is 50%:50%, prepare the required ryegrass compound fertilizer.

[0044] (2) The waste powder collected and recycled by the asphalt mixing plant is passed through a 2mm sieve to remove impurities and weighed according to the required number of parts. 60 parts of recycled powder are added to the mixing mixer. At the same time, the amount of other added materials is calculated according to the amount of recycled powder and the required addition ratio and weighed for later use.

[0045] (3) Add an appropriate amount of water to the mixing mixer with the added recycled powder to increase the moisture content of the recycled powder to 10% and stir for 3 minutes to moisten it evenly; first, evenly sprinkle the weighed 2 portions of furfural residue into the mixing mixer, then start the mixing mixer and stir for 5 minutes to mix the furfural residue and recycled powder evenly.

[0046] (4) After the furfural residue and recycled powder are mixed evenly in step (3), the mixture is evenly sprinkled into a continuous mixing mixer in the following order: 0.2 parts of ryegrass formula fertilizer, 2 parts of water-retaining agent, 3 parts of mushroom bran, 6 parts of vermiculite, 21.8 parts of bio-organic fertilizer and 5 parts of decomposed cow manure. Each group of added materials is added in sequence after the previous group of added materials and the aforementioned recycled powder mixture are mixed evenly. The mixer is stopped when all the mixtures are evenly mixed to obtain ryegrass nutrient soil for landscaping.

[0047] The nutrient content of the prepared ryegrass nutrient soil is shown in Table 1.

[0048] Table 1. Nutrient content of the prepared ryegrass nutrient soil

[0049]

[0050] Verification experiment: The recycled powder from the asphalt mixing plant was obtained from Shandong Ludong Road and Bridge Co., Ltd. The unmodified recycled powder was the control (CK) treatment, and the nutrient soil for landscaping ryegrass prepared in Example 1 was the treatment in Example 1. There were two treatments in total, with each treatment replicated three times. A potted ryegrass experiment was conducted on May 13, 2024, and the number of days and the emergence rate of ryegrass seedlings were monitored. The plant height, aboveground ryegrass biomass fresh weight, and dry weight at the first harvest on July 10, 2024 are shown in Table 2.

[0051] Table 2. Emergence and growth indicators of ryegrass under different experimental treatments at the time of first harvest.

[0052]

[0053] Note: The indicator data are mean ± standard error. The same lowercase letter after the data in the same column indicates that the difference between different treatments is not significant. P ≤0.05).

[0054] As shown in Table 1, compared with the unimproved recycled powder, the nutrient soil for ryegrass in Example 1 of this invention significantly improved the germination rate, plant height at the first cut, and aboveground biomass fresh and dry weight of ryegrass, except for having no difference in the number of days to germination. This indicates that the nutrient soil for ryegrass prepared by improving the recycled powder from asphalt mixing plants is beneficial to the germination and growth of ryegrass, and that this nutrient soil and its preparation method have significant application potential and value in turfgrass cultivation.

[0055] Example 2

[0056] Landscaping seedlings: Cypress seedlings

[0057] The asphalt mixing plant recycled powder garden greening nutrient soil described in Example 2 is composed of the following raw materials by weight: 70 parts recycled powder, 20 parts bio-organic fertilizer, 3.5 parts decomposed cow manure, 2 parts mushroom bran, 1 part furfural residue, 2 parts vermiculite, 0.5 parts greening seedling formula fertilizer, and 1 part water-retaining agent.

[0058] in:

[0059] The recycled powder is waste powder collected and recycled from asphalt mixing plants, with a particle size ≤2mm and a moisture content of 3%, and is taken from Shandong Ludong Road and Bridge Co., Ltd.

[0060] The bio-organic fertilizer is a commercially available organic fertilizer product that meets the standard of "NY 884-2012 Bio-organic Fertilizer". It was purchased from Shandong Lianyou Biotechnology Co., Ltd., with an organic matter content of ≥30% and total nutrients (N+P2O5+K2O) of ≥4%. The purpose is to increase the organic matter content of the recycled powder and improve its biological properties, stimulate the activity of beneficial microorganisms, and enhance biological fertility.

[0061] The decomposed cow manure is commercially available fermented and decomposed cow manure that meets the standard of "NY / T 525-2021 Organic Fertilizer" and was purchased from Shandong Lianyou Biotechnology Co., Ltd.; the purpose is not only to increase the organic matter in the recycled powder, but also mainly to improve the structure of the recycled powder with the fiber of the decomposed cow manure and promote the development of the recycled powder structure.

[0062] The mushroom residue is an organic material obtained by sterilizing, disinfecting, and crushing the discarded mushroom logs after mushroom harvesting. The particle size is ≤2mm and the moisture content is 2.5%. It was purchased from Shandong Lianyou Biotechnology Co., Ltd. The mushroom residue is mainly used to increase carbon content and improve the physical properties of the recycled powder, such as porosity, air permeability, and water permeability.

[0063] The furfural residue is a waste product left over from the production of furfural from corn cobs. It is rich in cellulose, lignin and a small amount of sulfuric acid, with a pH of 2, and was purchased from Shandong Lianyou Biotechnology Co., Ltd. Adding furfural residue can increase the organic matter in the recovered powder, reduce the acidity and alkalinity of the recovered powder, and regulate its chemical properties.

[0064] The vermiculite is a 2:1 type expansive layered aluminosilicate clay mineral with good permeability and strong water and fertilizer retention capacity. It is a commonly used soil conditioner and is often used as a substrate material for garden flowers. The particle size is ≤1mm and it was purchased from the local flower market. The purpose of adding vermiculite is to adjust the porosity and water and fertilizer retention performance of the recycled powder and improve its physical fertility.

[0065] The aforementioned greening seedling formula fertilizer is a fertilizer containing nutrient elements and conforming to the standard of "GB / T 21633-2020 Blended Fertilizers (BB Fertilizer)" formulated according to the nutrient requirements of greening seedlings. It uses nutrient element fertilizers purchased from the local agricultural input market. Its raw materials are: urea, ammonium sulfate, monoammonium phosphate, diammonium phosphate, superphosphate, triple superphosphate, potassium sulfate, calcium sulfate, magnesium sulfate, ferrous sulfate, manganese sulfate, zinc sulfate, borax, and coated slow-release urea (release period of 3 months, N 42%), which are blended together. The ratio of slow-release nitrogen to fast-release nitrogen is 80%:20%, which is used to improve the recovery of powder nutrients, balance its nutrition, regulate its slow-release and fast-release nutrient ratio, and enhance its chemical fertility.

[0066] The fertilizer for greening seedlings is formulated for cypress seedlings.

[0067] The water-retaining agent is a soil conditioner that conforms to the standard "NY / T 886-2022 Agricultural and Forestry Water-Retaining Agent" and regulates water retention. Polyacrylamide is selected, and its main purpose is to improve the water and fertilizer retention of the recycled powder and improve its structure.

[0068] The method for preparing nutrient soil for landscaping using recycled powder from asphalt mixing plants, as described in Example 2, comprises the following steps:

[0069] (1) First, according to the fertilizer requirements of cypress seedlings, the N-P2O5-K2O ratio is 20-10-10 and the ratio of slow-release nitrogen is 80%:20%, prepare the required cypress seedling formula fertilizer.

[0070] (2) The waste powder collected and recycled by the asphalt mixing plant is passed through a 2mm sieve to remove impurities and weighed according to the required number of parts. 70 parts of recycled powder are added to the mixing mixer. At the same time, the amount of other added materials is calculated according to the amount of recycled powder and the required addition ratio and weighed for later use.

[0071] (3) Add an appropriate amount of water to the mixing mixer with the added recycled powder to increase the moisture content of the recycled powder to 15% and stir for 5 minutes to moisten it evenly; first, evenly sprinkle 1 part of the weighed furfural residue into the mixing mixer, then start the mixing mixer and stir for 10 minutes to mix the furfural residue and the recycled powder evenly.

[0072] (4) After the furfural residue and recycled powder are mixed evenly in step (3), the mixture is evenly sprinkled into the continuous mixing mixer in the following order: 0.5 parts of cypress seedling formula fertilizer, 1 part of water-retaining agent, 2 parts of mushroom bran and 2 parts of vermiculite, 20 parts of bio-organic fertilizer and 3.5 parts of decomposed cow manure. Each group of added materials is added in sequence after the previous group of added materials and the aforementioned recycled powder mixture are mixed evenly. The mixer is stopped when all the mixtures are evenly mixed to obtain cypress nutrient soil for landscaping.

[0073] The nutrient content of the prepared cypress nutrient soil is shown in Table 3.

[0074] Table 3. Nutrient-related status of the prepared cypress nutrient soil

[0075]

[0076] Verification experiment: The recycled powder from the asphalt mixing plant was obtained from Shandong Ludong Road and Bridge Co., Ltd. The unmodified recycled powder served as the control (CK) treatment, and the nutrient soil for juniper seedlings prepared in Example 2 served as the Example 2 treatment. There were two treatments in total, with each treatment replicated 10 times. On April 9, 2024, a pot experiment was conducted using 3-year-old juniper seedlings. On July 9, 2024, the survival rate of the juniper seedlings was monitored. At least 3 surviving plants were selected to monitor plant height and biomass growth. The results are shown in Table 4.

[0077] Table 4 Survival rate, plant height, and biomass of *Juniperus chinensis* seedlings under different experimental treatments

[0078]

[0079] Note: The index data are the mean ± standard error. The same lowercase letter after the data in the same column indicates that the difference between different treatments is not significant (P≤0.05).

[0080] As shown in Table 2, compared with the control CK treatment without improved recycled powder, the survival rate of the cypress seedlings in Example 2 was 14.29% higher, and the plant height and overall biomass growth were significantly higher than those in the control CK treatment. This indicates that the nutrient soil for cypress seedlings prepared with the improved recycled powder from the asphalt mixing plant is beneficial to the survival of cypress seedlings and promotes their growth. It has broad prospects for practical application and promotion in landscaping seedlings.

Claims

1. A method for preparing nutrient soil for landscaping using recycled powder from asphalt mixing plants, characterized in that: The recycled powder nutrient soil for landscaping produced by asphalt mixing plants is composed of the following raw materials by weight: 50-75 parts recycled powder, 20-45 parts bio-organic fertilizer, 3-25 parts decomposed cow manure, 2-10 parts mushroom residue, 1-5 parts furfural residue, 2-15 parts vermiculite, 0.2-0.5 parts formulated fertilizer for greening seedlings, and 1-5 parts water-retaining agent. Wherein: the recycled powder is waste powder collected and recycled by asphalt mixing plants, with a particle size ≤2mm and a moisture content ≤5%; The mushroom substrate is an organic material obtained by sterilizing, disinfecting, and crushing the discarded mushroom substrate after harvesting. The particle size is ≤2mm and the moisture content is ≤3%. The furfural residue is the waste remaining after the production of furfural from corn cobs; The vermiculite is a 2:1 type expansive layered aluminosilicate clay mineral; The water-retaining agent is one of polyacrylamide, starch-polyacrylamide, carboxymethyl cellulose, or polyacrylonitrile; The method for preparing nutrient soil for landscaping using recycled powder from asphalt mixing plants consists of the following steps: (1) First, based on the fertilizer requirements of garden greening seedlings and the requirements for the ratio of slow-release and fast-release nitrogen, select macro-, medium and micronutrient fertilizer raw materials to prepare the required greening seedling formula fertilizer; (2) After removing impurities by passing the recycled powder through a 2 mm sieve, weigh the required amount and add the recycled powder to the mixing mixer. At the same time, calculate the amount of other added materials according to the amount of recycled powder and the required addition ratio, and weigh them for later use. (3) Sprinkle clean water into the mixing mixer with the added recycled powder to increase the moisture content of the recycled powder to 10% to 15% and stir for 3 to 5 minutes to moisten it evenly; first, evenly sprinkle the weighed furfural residue into the mixing mixer, and then start the mixing mixer to stir for 5 to 10 minutes to mix the furfural residue and the recycled powder evenly. (4) After the furfural residue and recycled powder are mixed evenly in step (3), they are evenly sprinkled into the continuous mixing mixer in the following order: green seedling formula fertilizer and water-retaining agent, mushroom residue and vermiculite, biological organic fertilizer and decomposed cow manure. Each group of added materials is added in sequence after the previous group of added materials and the aforementioned recycled powder mixture are mixed evenly. The mixer is stopped when all the mixtures are evenly mixed, and the recycled powder garden greening nutrient soil of the asphalt mixing plant is prepared.

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