Preparation method of plant culture composite substrate capable of realizing solid waste recycling

Abstract

The invention belongs to the technical field of soil improvement, and particularly relates to a preparation method of a plant culture compound substrate for realizing solid waste recycling. The plant culture composite matrix is composed of coal gangue, fly ash, biochar, activated sludge and barren soil, and the mass ratio of the coal gangue to the activated sludge is 5: 8. The plant culture composite substrate can effectively improve the fertility of barren soil, promote vegetation recovery, achieve effective utilization of the barren soil, solve the problem that a large amount of coal gangue and coal ash are accumulated, achieve resource utilization of mining area waste and have potential practical engineering application prospects.

Description

Technical Field

[0001] The present invention belongs to the technical field of soil improvement, and particularly relates to a preparation method of a plant cultivation composite substrate for realizing the reuse of solid waste. Background Art

[0002] Coal gangue is a solid waste in the process of coal mining and washing. Fly ash mainly comes from the industrial waste residue discharged from the coal powder boilers of thermal power plants. Straw contains elements such as nitrogen, phosphorus, potassium, magnesium, calcium and sulfur, which are essential nutrient elements for biological growth. Straw can improve the soil structure, enhance the soil's self-regulating ability of water, fertilizer, air and heat, and optimize the soil environment.

[0003] Biochar is a type of functional carbon material, and its main constituent elements are C, H, and O. Common raw materials include sludge waste, feces, agricultural and forestry waste. Biochar can increase the pH of the soil and the concentrations of available phosphorus, available potassium and available magnesium, and at the same time can improve soil fertility, improve soil physical and chemical properties, increase crop yields, adsorb various pollutants and improve the bioavailability of soil nutrient elements.

[0004] Sludge contains a large amount of organic matter, nitrogen, phosphorus and other nutrient elements, and has high value. It can be used as a soil conditioner and fertilizer, which helps to improve soil fertility and crop yields. However, the composition of sludge is complex, and it may contain harmful substances such as heavy metals, viruses, and parasite eggs. If not properly disposed of, it will not only cause waste of resources, but also cause environmental pollution. The harmful substances in sludge may pollute groundwater and the atmosphere due to rain erosion and percolation, causing secondary pollution and harm to the environment and human health.

[0005] Therefore, the resource utilization of these waste materials conforms to the concept of resource recycling, can reduce the treatment cost, and reduce the pressure on the environment. Summary of the Invention

[0006] The purpose of the present invention is to provide a preparation method of a plant cultivation composite substrate for realizing the reuse of solid waste, which can repair barren soil, improve the soil structure, and at the same time realize the resource utilization of mining waste.

[0007] The technical solution adopted by the present invention is:

[0008] A plant cultivation composite substrate for realizing the reuse of solid waste is composed of coal gangue, fly ash, biochar, activated sludge and barren soil.

[0009] Further, for the above-mentioned plant cultivation composite substrate for realizing the reuse of solid waste, the mass ratio of the coal gangue to the activated sludge is 5:8.

[0010] Furthermore, for the above plant cultivation composite substrate for realizing solid waste recycling, by mass percentage, the plant cultivation composite substrate is composed of 17.31% coal gangue, 10% fly ash, 5% biochar, 27.69% activated sludge, and 40% barren soil.

[0011] Furthermore, for the above plant cultivation composite substrate for realizing solid waste recycling, the pretreatment method of the coal gangue is: crushing and grinding the large coal gangue into a powder.

[0012] Furthermore, for the above plant cultivation composite substrate for realizing solid waste recycling, the fly ash is in powder form.

[0013] Furthermore, for the above plant cultivation composite substrate for realizing solid waste recycling, the activated sludge is the excess sludge from the secondary sedimentation tank of a municipal wastewater treatment plant.

[0014] Furthermore, for the above plant cultivation composite substrate for realizing solid waste recycling, the pretreatment method of the activated sludge is: drying and grinding the activated sludge, and passing it through a 2 mm sieve.

[0015] Furthermore, for the above plant cultivation composite substrate for realizing solid waste recycling, the pretreatment method of the barren soil is: air-drying the barren soil and passing it through a 2 mm sieve.

[0016] The beneficial effects of the present invention are as follows:

[0017] 1. The present invention proposes a preparation method of a plant cultivation composite substrate for realizing solid waste recycling. This substrate is simple to manufacture, low in cost, and has application prospects.

[0018] 2. In the present invention, the acidity and alkalinity of the coal gangue and various trace elements and nutrients contained therein can increase the fertilizer efficiency of the soil. The nutrient elements and trace elements contained in the fly ash provide conditions for the growth of plant roots. At the same time, the activated sludge supplements the essential nutrient elements such as nitrogen, phosphorus, and potassium for plant growth, and the biochar can increase soil air, looseness, and water retention capacity. By mixing the barren soil with the above components, the soil fertility can be effectively improved, and the missing nutrient elements in the barren soil can be supplemented; experiments show that the growth of plants has been greatly improved, proving that the substrate of the present invention is effective and reliable.

[0019] 3. The main components of the present invention are solid wastes such as coal gangue. Resource utilization of them can effectively alleviate the problems of occupying a large amount of land and polluting the environment; solid wastes such as coal gangue and fly ash are low in cost, reducing the economic cost, and having high economic and environmental benefits. Description of the Drawings

[0020] Figure 1 It is a comparison chart of the ryegrass biomass in composite substrates with different ratios. Specific Embodiments

[0021] Example 1

[0022] A plant cultivation composite substrate for realizing solid waste reuse is composed of coal gangue, fly ash, biochar, activated sludge and barren soil through mixing and processing. The specific steps of its preparation method are as follows:

[0023] (I) Preparation of experimental materials

[0024] (1) Crush and grind large coal gangue into powder.

[0025] (2) Air-dry the barren soil in the experimental plot and sieve it through a 2 mm sieve to remove plant residues, stones and other debris contained in the raw materials.

[0026] (3) Dry and grind the excess sludge in the secondary sedimentation tank of the urban sewage treatment plant, and sieve it through a 2 mm sieve.

[0027] (4) Powdered fly ash.

[0028] (5) Raise the selected ryegrass seeds at 25 °C.

[0029] (II) Preparation of composite substrate

[0030] (1) Sludge-straw-coal gangue composite substrate group

[0031] Mix coal gangue and activated sludge with straw, fly ash and barren soil respectively according to the mass ratios of 1:3, 5:8, 5:6 and 1:1 to prepare composite substrates, which are respectively denoted as A1 - A4. Each group is set with three replicates. The specific experimental group settings are shown in Table 1.

[0032] Table 1 Component table of each experimental group of sludge-straw-coal gangue composite substrate

[0033] Substrate number Coal gangue Fly ash Straw Activated sludge Barren soil A1 11.25％ 10％ 5％ 33.75％ 40％ A2 17.31％ 10％ 5％ 27.69％ 40％ A3 20.45％ 10％ 5％ 24.55％ 40％ A4 22.5％ 10％ 5％ 22.5％ 40％

[0034] (2) Sludge-biochar-coal gangue composite substrate group

[0035] Mix coal gangue and activated sludge with biochar, fly ash and barren soil respectively according to the mass ratios of 1:3, 5:8, 5:6 and 1:1 to prepare composite substrates, which are respectively denoted as B1 - B4. Each group is set with three replicates. The specific experimental group settings are shown in Table 2.

[0036] Table 2 Component table of each experimental group of sludge-biochar-coal gangue composite substrate

[0037] Substrate number Coal gangue Fly ash Biochar Activated sludge Barren soil B1 11.25％ 10％ 5％ 33.75％ 40％ B2 17.31％ 10％ 5％ 27.69％ 40％ B3 20.45％ 10％ 5％ 24.55％ 40％ B4 22.5％ 10％ 5％ 22.5％ 40％

[0038] (III) Plant cultivation and post-cultivation maintenance

[0039] (1) Select ryegrass seedlings with consistent growth and transplant them into the above different composite substrates (3 seedlings per pot);

[0040] (2) After transplanting the seedlings, the cultivation temperature is 25 °C, maintaining sufficient light and humidity, watering once a day, with an interval not exceeding 24 hours.

[0041] (4) Analyze and measure the experimental results 8 days after the seedlings are planted

[0042] The analysis of the experimental results of this example is as follows:

[0043] Table 3 Plant biomass situation table of each composite substrate experimental group

[0044] Substrate number Biomass Substrate number Biomass A1 0.0343 B1 0.0384 A2 0.0345 B2 0.0508 A3 0.0255 B3 0.0243 A4 0.0275 B4 0.0315

[0045] As can be seen from Table 3 and Figure 1 it can be known that the plant biomass of the sludge-biochar-gangue composite substrate group is generally higher than that of the sludge-straw-gangue composite substrate group. The biomass size order of the sludge-straw-gangue composite substrate group is: A2 > A1 > A4 > A3, and the plant biomass size order of the sludge-biochar-gangue composite substrate group is: B2 > B1 > B4 > B3. It can be seen that the best formula for the composite substrate is: 17.31% gangue, 10% fly ash, 5% biochar, 27.69% activated sludge and 40% barren soil.

Claims

1. A plant culture composite matrix for realizing solid waste recycling, characterized in that: The plant culture composite matrix is ​​composed of coal gangue, fly ash, biochar, activated sludge and barren soil.

2. A plant cultivation composite matrix for realizing solid waste recycling according to claim 1, characterized in that: The mass ratio of the coal gangue to the activated sludge is 5:

8.

3. A composite plant culture matrix for realizing solid waste recycling according to claim 2, characterized in that: By mass percentage, the plant culture composite matrix is ​​composed of 17.31% coal gangue, 10% fly ash, 5% biochar, 27.69% activated sludge and 40% barren soil.

4. A plant cultivation composite matrix for realizing solid waste recycling according to claim 1, characterized in that: The pretreatment method of the coal gangue is: crushing and grinding the large pieces of coal gangue into powder.

5. The plant cultivation composite matrix for realizing solid waste recycling according to claim 1, characterized in that: The fly ash is in powder form.

6. The plant cultivation composite matrix for realizing solid waste recycling according to claim 1, characterized in that: The activated sludge is the residual sludge from the secondary sedimentation tank of the urban sewage treatment plant.

7. The plant cultivation composite matrix for realizing solid waste recycling according to claim 1, characterized in that: The activated sludge pretreatment method is: drying the activated sludge, grinding it, and passing it through a 2mm sieve.

8. The plant cultivation composite matrix for realizing solid waste recycling according to claim 1, characterized in that: The pretreatment method of the barren soil is as follows: after the barren soil is air-dried, it is passed through a 2 mm sieve.

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