A solid waste treatment method and its application in the manufacture of composite soil

Abstract

This invention relates to a solid waste treatment method and its application in the manufacture of composite soil, belonging to the field of solid waste treatment and composite soil preparation. Using solid waste sludge as raw material, it includes an odor removal process. The odor removal process is as follows: after drying the solid waste sludge, it is mixed with a self-made enzyme aqueous solution and piled up to remove odor. The odor can be eliminated within 3 minutes. The harmlessly treated original soil is then mixed with a certain amount of topsoil to be used as artificial soil, effectively realizing the reuse of urban solid waste and the reclamation of subsidence areas.

Description

Technical Field

[0001] This invention relates to the field of solid waste treatment and composite soil preparation technology, specifically to a solid waste treatment method and its application in the manufacture of composite soil. Background Technology

[0002] Land reclamation refers to the activities of restoring land damaged by excavation, subsidence, or occupation during production and construction to a state suitable for cultivation. Currently, the reclamation of subsided land and land reclamation mainly utilize nearby soil, taking local resources and digging deep and filling shallow.

[0003] Existing land reclamation technologies have the following drawbacks:

[0004] 1. High cost of filler materials: Filler materials (topsoil) need to be purchased, which is costly, and the land can only be cultivated after filling is completed;

[0005] 2. Large workload, high cost and low efficiency: The current method of deep excavation and shallow filling involves a very large workload, resulting in high cost and low efficiency, and the land can only be restored to its original state after completion.

[0006] 3. The shortage of imported soil makes large-scale purchases difficult, mainly due to low production capacity, lack of energy efficiency, and high costs, which will eventually lead to land reclamation after completion.

[0007] Existing technologies include reports on the production of artificial soil using coal-based solid waste as raw materials. This involves using gangue, fly ash, organic solid waste, desert sand, silt, and biological agents as raw materials, and then biologically treating the solid waste to form soil. For example, Chinese invention patent application number 202011099312.4 discloses a method for producing soil from shale gas water-based drill cuttings. This method uses water-based drill cuttings as raw materials, sequentially treating them with water washing and desalination, and then adding purple soil and cow dung fermentation products to the mixture to obtain artificial soil. However, there are currently no methods for producing artificial soil using urban solid waste.

[0008] Currently, the main method for treating urban solid waste is incineration. This method requires a large amount of auxiliary materials, resulting in high incineration costs, and it also causes secondary environmental pollution. Furthermore, the ash from incineration is then disposed of in landfills, incurring additional costs and wasting land resources. In addition, urban solid waste is sometimes used as raw material for compressed bricks, but due to the lack of thorough and harmless treatment, there is a risk of pollution leakage and secondary pollution.

[0009] Among the various aspects of urban solid waste treatment, deodorization is the most challenging step. The commonly used method is biological fermentation, but this method is time-consuming and has poor deodorization effects. Summary of the Invention

[0010] This invention addresses the aforementioned problems in the prior art by providing a solid waste treatment method and its application in the manufacture of composite soil. On the one hand, the solid waste treatment process has the advantage of rapid odor removal. On the other hand, after harmless treatment, solid waste sludge is transformed into valuable material for use in composite soil, meeting the requirements for planting crops and being used for graded landfilling of subsidence areas to achieve the purpose of land reclamation. This solves the problems of existing soil shortage and solid waste pollution.

[0011] The technical solution of the present invention to solve the above-mentioned technical problems is as follows:

[0012] On the one hand, the present invention provides a solid waste treatment method, characterized by using solid waste sludge as raw material, including an odor removal process.

[0013] The odor removal process is as follows: after drying the solid waste sludge, it is mixed with an enzyme aqueous solution and then piled up to remove odors.

[0014] Furthermore, the solid waste sludge comes from municipal wastewater treatment plant sludge, enterprise wastewater treatment plant sludge identified as general solid waste, enterprise production-generated general solid waste sludge, and river dredging sludge.

[0015] Furthermore, the enzyme is: the product of mineral powder after being piled and fermented with a carbon source; specifically, it is fermented at 25-32℃ for 15-20 days, and stirred once every 12 hours;

[0016] Furthermore, the ore powder is made from at least one of slate, conglomerate, igneous rock, and sedimentary rock.

[0017] Furthermore, the carbon source is at least one of starch, vegetables, or fruits.

[0018] Furthermore, the amount of enzyme added relative to the solid waste sludge is 0.1-3%.

[0019] On the other hand, the present invention provides the application of the above-mentioned solid waste treatment method in the manufacture of composite soil, characterized in that the material after odor removal treatment is subjected to harmless treatment and exhaust to form original soil, and imported soil is added to the original soil in proportion to obtain composite soil.

[0020] Further, the harmless treatment involves: after odor removal, using quicklime to adjust the pH of the material to 7-9, adding antibacterial agents and antimicrobial activators, and then maturing it; the exhaust process involves: pressurizing or vacuuming the harmlessly treated material to increase the compactness of the sludge.

[0021] Furthermore, the antibacterial agent includes sludge antibacterial agent, bioflocculant, and bioenzyme; wherein the sludge antibacterial agent is at least one of predatory protozoa, Bacillus, Actinomycetes, and filamentous fungi; the bioflocculant is at least one of yeast cell wall dextran, mannan, protein, and N-acetylglucosamine; the bioenzyme is lysozyme, hydrolase, and lyase; and the antibacterial activator is the enzyme.

[0022] Furthermore, sandy substances, ash, organic matter, and microorganisms are added to the original soil to adjust its fertility, clay, sandiness, pH, C / N ratio, and porosity. Among them, the sandy substances are fly ash, lime powder, and wood ash, and the added microorganisms include at least rhizobia, nitrifying bacteria, and denitrifying bacteria.

[0023] The beneficial effects of this invention are:

[0024] 1. This invention uses a self-made enzyme aqueous solution to deodorize dried solid waste sludge. An enzyme addition of 0.1-3% relative to the solid waste sludge can achieve rapid deodorization, specifically within 3 minutes; it solves the fundamental technical problem that hinders the reuse of urban solid waste sludge.

[0025] 2. This invention innovatively uses the product obtained by fermenting mineral powder with added carbon source for the removal of odors from solid waste sludge. It has the advantages of low dosage and fast odor removal effect, which cannot be achieved by conventional deodorizing agents.

[0026] 3. This invention innovatively uses solid waste sludge to prepare composite soil. First, after multi-stage harmless treatment, the original soil is prepared. Its basic soil properties are then tested. Based on the test results and planting needs, the fertility, cohesion, sandiness, pH, C / N ratio, and porosity of the original soil are adjusted by adding sandy substances, ash, organic matter, and microorganisms. Then, it is mixed with imported soil (the amount of imported soil added is only about 1%) to obtain composite soil that meets the requirements for planting crops. Finally, the subsidence area is filled in stages to achieve the purpose of reclaiming land for cultivation. At the same time, it solves the problems of existing imported soil resource shortage and solid waste pollution, and fills the gap in existing technology for preparing composite soil from solid waste. Detailed Implementation

[0027] The principles and features of the present invention are described below. The embodiments given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0028] Example 1

[0029] The solid waste sludge treatment steps in this embodiment are as follows:

[0030] Homemade enzyme: The product is made by adding carbon source starch to slate ore powder and fermenting it at 25-32℃ for 20 days; the fermented product is then prepared into a 10% enzyme aqueous solution.

[0031] Using solid waste sludge from municipal wastewater treatment plants as raw material, the sludge was first dried, and then an enzyme aqueous solution was added. The enzyme was added at 0.1% of the weight of the solid waste sludge. After mixing and piling for 3 minutes, no obvious odor residue was found, and the deodorization effect was excellent.

[0032] Use quicklime to adjust the pH of the material to about 7, add 1% of antibacterial agent (sludge antibacterial agent such as predatory protozoa, Bacillus, Actinomycetes, filamentous fungi, as well as yeast cell wall glucan and lysozyme), and 0.5% of antibacterial activator (enzyme aqueous solution), and pile it at room temperature for 5 days for maturation.

[0033] Vacuuming is used to remove air and increase the compactness of the sludge, thus obtaining the original soil.

[0034] According to the intended use of the soil, add appropriate amounts of fly ash, lime powder, wood ash, ash, organic matter, and microorganisms (0.01% rhizobium, 0.01% nitrifying bacteria, and 0.01% denitrifying bacteria) to the original soil, and then add imported soil at a ratio of 1% to obtain composite soil.

[0035] Example 2

[0036] The solid waste sludge treatment steps in this embodiment are as follows:

[0037] Homemade enzyme: The product is made by adding mineral powders of slate, conglomerate, igneous rock, and sedimentary rock to carbon source vegetables and fruits, and then fermenting them at 25-32℃ for 20 days; the fermented product is then prepared into a 10% enzyme aqueous solution.

[0038] Using general solid waste sludge generated by enterprises as raw material, it is first dried, and then an enzyme aqueous solution is added to it. The enzyme is added at 2% of the weight of the solid waste sludge. After mixing and piling for 2.5 minutes, there is no obvious odor residue, and the deodorization effect is excellent.

[0039] Use quicklime to adjust the pH of the material to about 7, add 1% of antibacterial agent (sludge antibacterial agent such as predatory protozoa, Bacillus, Actinomycetes, filamentous fungi, as well as yeast cell wall glucan and lysozyme), and 0.5% of antibacterial activator (enzyme aqueous solution), and pile it at room temperature for 5 days for maturation.

[0040] Vacuuming is used to remove air and increase the compactness of the sludge, thus obtaining the original soil.

[0041] According to the intended use of the soil, add appropriate amounts of fly ash, lime powder, wood ash, ash, organic matter, and microorganisms (0.01% rhizobium, 0.01% nitrifying bacteria, and 0.01% denitrifying bacteria) to the original soil, and then add imported soil at a ratio of 1% to obtain composite soil.

[0042] Example 3

[0043] The solid waste sludge treatment steps in this embodiment are as follows:

[0044] Homemade enzyme: The product is made by adding carbon source starch and vegetables and fruits to igneous rock ore powder and fermenting it for 18 days at 25-32℃; the fermented product is then prepared into a 10% enzyme aqueous solution.

[0045] Using dredged sludge from river treatment as raw material, the sludge was first dried, and then an enzyme solution was added to it. The enzyme was added at 3% of the weight of the solid waste sludge. After mixing and piling for 2 minutes, no obvious odor residue was found, and the deodorization effect was excellent.

[0046] Use quicklime to adjust the pH of the material to about 7, add 1% of antibacterial agent (sludge antibacterial agent such as predatory protozoa, Bacillus, Actinomycetes, filamentous fungi, as well as yeast cell wall glucan and lysozyme), and 0.5% of antibacterial activator (enzyme aqueous solution), and pile it at room temperature for 5 days for maturation.

[0047] Vacuuming is used to remove air and increase the compactness of the sludge, thus obtaining the original soil.

[0048] According to the intended use of the soil, add appropriate amounts of fly ash, lime powder, wood ash, ash, organic matter, and microorganisms (0.01% rhizobium, 0.01% nitrifying bacteria, and 0.01% denitrifying bacteria) to the original soil, and then add imported soil at a ratio of 1% to obtain composite soil.

[0049] Currently, the composite soil prepared by the above embodiments of the present invention has been applied to mine restoration in non-ferrous metal mining areas in Hunan Province, realizing the restoration of mining areas. It is of great significance in actual production to simultaneously solve solid waste treatment, the shortage of topsoil resources, and the restoration of subsidence areas.

Claims

1. A method of manufacturing a composite soil, characterized by, The solid waste sludge is used as raw material, including an odor removal process, and the material after the odor removal treatment is formed into raw soil after harmless treatment and exhaust, and the raw soil is mixed with guest soil to obtain composite soil; The odor removal process is: after drying the solid waste sludge, the sludge is mixed with an enzyme aqueous solution, and then odor removal is performed within 3 minutes; The harmless treatment is: after the odor removal treatment, the pH of the material is adjusted to 7-9 by using quicklime, and a bacteriostatic agent and a bacterium-inhibiting activator are added for curing; The exhaust is: the material after the harmless treatment is pressurized or vacuumed to increase the compactness of the sludge; The enzyme is: a product obtained by stacking and fermenting mineral powder after adding a carbon source; The mineral powder is at least one of slate, conglomerate, magmatic rock and sedimentary rock, and the carbon source is at least one of starch and vegetables and fruits; The solid waste sludge is from municipal sewage treatment plant sludge, sludge of enterprise sewage treatment plant identified as general solid waste, general solid waste sludge generated in enterprise production, and river channel treatment dredging sludge; The addition amount of the enzyme relative to the solid waste sludge is 0.1-3%; The bacteriostatic agent includes sludge bacteriostatic agent, biological flocculant and biological enzyme; the sludge bacteriostatic agent is at least one of predatory protists, bacillus, actinomycetes and filamentous bacteria, the biological flocculant is at least one of glucan, mannan, protein and N-acetylglucosamine of yeast cell wall, and the biological enzyme is lysozyme, hydrolase and lyase; and the bacterium-inhibiting activator is the enzyme.