Method for repairing and treating landfill

Abstract

A method for repairing and treating a landfill, relating to the technical field of waste treatment, and comprising: determining the degree of stabilization of each waste pile in a landfill; when the degree of stabilization of the waste pile meets a preset standard, performing a first waste treatment step; when the degree of stabilization of the waste pile does not meet the preset standard, performing aerobic stabilization pretreatment and performing a preset second waste treatment step; and performing ecological restoration treatment, so that the repaired landfill meets a preset use standard, wherein the first waste treatment step is performed in an area adjacent to the waste pile, and the second waste treatment step is performed in an area where the waste pile is located. Thus, by combining in-situ repair and ex-situ repair, harmlessness, reduction and recycling treatment of the waste pile are achieved, and the impact of leachate, odor, noise, soil and water loss, and the like during repair on the ecological environment can be strictly controlled.

Description

Landfill remediation method TECHNICAL FIELD

[0001] The present application relates to the field of waste treatment, in particular to a landfill remediation method. BACKGROUND

[0002] A landfill is a common waste disposal facility. It is a specific area with corresponding equipment, which collects and stores waste from cities, industries and other sources after a series of collection, transportation, stacking, compaction and covering operations.

[0003] Landfill remediation refers to a series of operations to repair and manage existing or abandoned landfills to reduce environmental pollution and improve the value of land resources for reuse.

[0004] It usually combines the use of land reclamation technology, wastewater treatment technology, gas control technology, bioremediation technology, geographic information system (GIS) technology and resource reuse technology, etc. to reduce the risk of environmental pollution and improve the value of sustainable use of land resources.

[0005] However, the existing landfill remediation operations have defects such as high time and operating costs, low overall utilization level, and inability to effectively eliminate the impact on the ecological environment.

[0006] CONTENT

[0007] The present application aims to provide a landfill remediation method that can solve at least some of the defects of traditional landfill remediation.

[0008] In a first aspect, the embodiments of the present application provide the following technical solutions: a landfill remediation method. The method comprises: determining the stabilization degree of each garbage pile in the landfill; when the stabilization degree of the garbage pile meets the preset standard, performing a preset first garbage treatment step; when the stabilization degree of the garbage pile does not meet the preset standard, performing aerobic stabilization pretreatment by introducing oxygen and microbial inoculum into the garbage pile; and after the aerobic stabilization pretreatment is completed, performing a preset second garbage treatment step; performing ecological restoration treatment on the landfill where the garbage is treated by the first garbage treatment step and / or the second garbage treatment step, so that the repaired landfill meets the preset use standard; wherein the first garbage treatment step is performed in the adjacent area of the garbage pile; and the second garbage treatment step is performed in the area where the garbage pile is located.

[0009] Optionally, the second garbage treatment step comprises: excavating the garbage pile under the protection of the preset at least one protective measure; screening the stock of garbage obtained by excavating the garbage pile to form a plurality of different types of garbage; and performing a preset resource utilization treatment according to the characteristics of the different types of garbage to form a plurality of renewable resources.

[0010] Optionally, the step of aerobic stabilization pretreatment specifically comprises: passing oxygen into the garbage pile and adding facultative microorganism bacteria agent for stabilization treatment through an air injection system; and extracting air inside the garbage pile through an air extraction system; monitoring a plurality of different treatment indexes to determine the state of the garbage pile during the stabilization treatment, and controlling the air injection system and the air extraction system according to the state of the garbage pile; wherein the treatment indexes include pressure, flow, temperature, humidity, gas composition, and pile subsidence; the air injection wells of the air injection system are arranged in an equidistant quincunx or cross shape, and the air extraction system is provided with an air filtering device for filtering air from inside the garbage pile.

[0011] Optionally, the protective measures include: setting up a three-dimensional deodorization system to remove odor during the excavation of the garbage pile; wherein the three-dimensional deodorization system includes an air-filled greenhouse surrounding the garbage pile, an air deodorization device on the excavation operation surface, and a spray deodorization device located on the periphery of the air-filled greenhouse.

[0012] Optionally, the second garbage treatment further comprises: collecting leachate generated during the excavation of the garbage pile through a leachate collection system; and treating the leachate using a preset sewage treatment process; wherein the preset sewage treatment process specifically comprises: pretreating the collected leachate to form homogeneous wastewater to be treated; treating the wastewater to be treated through a reverse osmosis concentration system to obtain wastewater meeting discharge standards; and treating concentrated liquid generated by the reverse osmosis concentration system through evaporation crystallization technology.

[0013] Optionally, the treatment of the wastewater to be treated by the reverse osmosis concentration system specifically comprises: passing the wastewater to be treated through a two-stage DTRO system to form first effluent and first concentrated liquid; storing the first concentrated liquid in a concentrated liquid tank; passing the first concentrated liquid stored in the concentrated liquid tank through a two-stage HPRO treatment system to form second effluent and second concentrated liquid; collecting the first effluent and the second effluent into a degassing tower for degassing treatment to obtain effluent after removal of free carbon dioxide; treating the effluent after removal of free carbon dioxide by an ion exchanger to obtain the wastewater meeting the discharge standard; and treating the concentrated liquid generated by the reverse osmosis concentration system by an evaporation crystallization technology, specifically comprising: evaporating the second concentrated liquid by an evaporator to form crystallized salt and condensed liquid; returning the condensed liquid to the input end of the two-stage HPRO treatment system for reverse osmosis treatment again; solidifying and drying the crystallized salt to form tailings; and the tailings can be used for backfilling of the landfill site.

[0014] Optionally, the screening treatment of the inventory garbage obtained by excavating the garbage pile specifically comprises: placing the inventory garbage excavated from the garbage pile in a sunning area for drying, and collecting leachate generated in the sunning area by the leachate collector; transporting the inventory garbage dried in the sunning area to a first vibrating screen for sorting, and sorting out brick and stone blocks with a size greater than a preset first standard from the inventory garbage; transporting the remaining inventory garbage after the first vibrating screen sorting to a magnetic separator for sorting, and sorting out metal therefrom; transporting the remaining inventory garbage after sorting out metal to a plurality of drum screens and air separators, and sorting out humus soil, a plurality of brick and stone blocks with different sizes, and light materials according to a preset sorting mode.

[0015] Optionally, the sunning area is a hardened concrete ground surface provided with a slope of 3 ‰; a leachate drainage ditch is arranged on the outer periphery of the sunning area, a steel grating cover plate is arranged on the leachate drainage ditch, and a surface water drainage ditch is further arranged on the outer periphery of the leachate drainage ditch; wherein, the sunning area is further covered with a removable double-surface geomembrane during rainfall; the double-surface geomembrane has a thickness of 0.75 mm; and the double-surface geomembrane is removed when there is no rainfall.

[0016] Optionally, the remaining amount of garbage after sorting out the metal is sorted into humus, brick and stone tile blocks with a size greater than a second standard, and light materials according to a preset sorting mode, specifically including: the remaining amount of garbage after sorting out the metal is sorted through a first drum screen to form oversize material with a size greater than the second standard and undersize material with a size less than the second standard; the oversize material with a size greater than the second standard is screened through a first air separator to form brick and stone tile blocks with a size between the second standard and a first standard and light materials; the undersize material with a size less than the second standard is sorted through a second drum screen to form oversize material with a size greater than a third standard and undersize material with a size less than the third standard; the oversize material with a size greater than the third standard is screened through a second air separator to form brick and stone tile blocks with a size between the third standard and the second standard and light materials; the undersize material with a size less than the third standard is sorted through a third drum screen to form oversize material with a size greater than a fourth standard and humus with a size less than the fourth standard; the oversize material with a size greater than the fourth standard is screened through a second air separator to form brick and stone tile blocks with a size between the fourth standard and the third standard and light materials.

[0017] Optionally, the different types of garbage are subjected to a preset resource utilization treatment according to their characteristics to form various renewable resources, specifically including: the humus is subjected to a firing treatment to form building materials or ceramsite; the light materials are subjected to a cracking treatment to obtain fuel oil, combustible gas, and carbon black.

[0018] The garbage landfill site remediation method provided by the embodiments can realize harmless, reduction, and resource utilization of the garbage dump. In the remediation process, the ecological environmental impact of leachate, odor, noise, solid waste, water and soil loss, and the like in the whole life cycle of the landfill site remediation is strictly controlled. Moreover, the excavation and classification treatment of the stockpiled garbage in the garbage landfill site can effectively reduce the transportation distance and treatment cost of the garbage, the resource utilization level is high and economically reasonable, and the construction period can be effectively shortened. BRIEF DESCRIPTION OF DRAWINGS

[0019] One or more embodiments are illustrated by way of example in the figures that form a part of this patent document, and in which like reference numbers indicate similar elements as those found in several views. The drawings shown in the accompanying drawings are not necessarily to scale, unless otherwise indicated, and in which:

[0020] FIG. 1 is a method flowchart of a garbage landfill site remediation method provided by an embodiment of the present application;

[0021] FIG. 2 is a method flowchart of a garbage treatment step provided by an embodiment of the present application;

[0022] Fig. 3 is a schematic diagram of a sewage treatment process according to an embodiment of the present application;

[0023] Fig. 4 is a schematic diagram of a screening process of stockpiled garbage according to an embodiment of the present application;

[0024] Fig. 5 is a schematic diagram of a structure of a sunning area according to an embodiment of the present application. Embodiments of the present application

[0025] For the purpose of facilitating the understanding of the present application, the present application will be described in more detail below with reference to the accompanying drawings and specific embodiments. It should be noted that when an element is described as being "fixed to" another element, it can be directly on the other element or one or more intervening elements can be present therebetween. When an element is described as being "connected to" another element, it can be directly connected to the other element or one or more intervening elements can be present therebetween. The terms "upper", "lower", "inner", "outer", "bottom", and the like as used in the present specification indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are merely for the purpose of facilitating the description of the present application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", "third", and the like are merely for the purpose of description and cannot be understood as indicating or implying relative importance.

[0026] Unless otherwise defined, all technical and scientific terms used in the present specification have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. The terms used in the present specification are merely for the purpose of describing specific embodiments of the present application and are not intended to limit the present application. The term "and / or" used in the present specification includes any and all combinations of one or more of the associated listed items.

[0027] In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0028] Fig. 1 is a method for repairing and treating a landfill according to an embodiment of the present application. As shown in Fig. 1, the method for repairing and treating the landfill can include the following steps:

[0029] S100, determining the stabilization degree of each garbage pile in the landfill.

[0030] The "stabilization degree" refers to a series of standards or data indicators for characterizing whether the garbage pile is in a stable state. A garbage pile with a high stabilization degree generally indicates that the organic matter in the garbage has been mostly decomposed, the generation of harmful gases has been reduced, and the volume of the garbage is stable, etc.

[0031] Specifically, the data parameters for characterizing the degree of stabilization can include, but are not limited to, organic matter content, temperature, gas production, and waste volume stability, etc.

[0032] S200, when the degree of stabilization of the waste pile meets the preset standard, performing a preset first waste treatment step.

[0033] The preset standard is a judgment standard preset by the technician according to the actual needs, which can only distinguish whether different waste piles are stable, and is not limited here.

[0034] The "first waste treatment step" refers to a series of waste treatment steps for the stable waste pile. It can be carried out in the equipment workshop set in the adjacent or nearby area of the waste pile, to realize the treatment and recycling of the waste in the waste pile.

[0035] S300, when the degree of stabilization of the waste pile does not meet the preset standard, performing aerobic stabilization pretreatment by introducing oxygen and microbial inoculum into the waste pile.

[0036] In the case where the preset standard is not met, it means that the waste pile is temporarily in an unstable state and cannot be directly excavated and subjected to subsequent waste treatment steps. Therefore, the aerobic stabilization pretreatment can be appropriately performed by introducing oxygen and microbial inoculum to accelerate the waste pile into a suitable stable state.

[0037] Specifically, the steps of the aerobic stabilization pretreatment specifically include: introducing oxygen into the waste pile through the gas injection system and adding facultative microbial inoculum for stabilization treatment; and extracting the air inside the waste pile through the air extraction system to accelerate the degree of stabilization of the waste pile.

[0038] During the stabilization treatment of the waste pile using the gas injection system and the air extraction system, a plurality of different treatment indexes can be monitored to determine the state of the waste pile, and the gas injection system and the air extraction system can be controlled according to the monitored state of the waste pile.

[0039] The treatment indexes include, but are not limited to, pressure, flow, temperature, humidity, gas composition, and pile settlement. The gas injection wells of the gas injection system can be arranged in an equidistant quincunx or cross shape, and the diameter of each gas injection well can be controlled at 30cm~60cm, and the adjacent gas injection wells are spaced apart by 15m. The air extraction system can also be provided with an air filtration device for filtering the air from the inside of the waste pile to ensure the cleanliness of the discharged air.

[0040] In some cases, even if the landfill is closed for many years and stops using, the garbage pile may still exist CO and H2S gas beyond the personnel exposure limit and CH4 gas content to explosive limit. The whole garbage pile is still large in gas production, and the safety risk of toxic and harmful gas and flammable and explosive gas is still high, and it is in an unstable state.

[0041] Therefore, through the above-mentioned aerobic stabilization pretreatment, the effects of accelerating the biodegradation process of the stockpile of garbage, changing the internal environment of the garbage pile, rapidly eliminating malodorous gas, reducing moisture, and reducing the methane concentration of the pile can be achieved, thereby improving the stabilization degree of the garbage pile and providing a safe and reliable guarantee for the subsequent excavation and treatment of the stockpile of garbage.

[0042] In addition, the alcoholization and acidification process using microbial fermentation can also convert liquid organic matter with a large molecular weight and high viscosity in the garbage into alcohol and acid with a small molecular weight and bring it into the leachate treatment.

[0043] S400, after the aerobic stabilization pretreatment is completed, a preset second garbage treatment step is performed.

[0044] The "second garbage treatment step" is also a series of garbage treatment steps for the stockpile of garbage in the garbage pile. It can be processed in the same way or similar to the above-mentioned first garbage treatment step to realize the treatment and recycling of the stockpile of garbage in the garbage pile.

[0045] S500, performing ecological restoration treatment on the landfill where the stockpile of garbage has been treated, so that the repaired landfill meets the preset use standard.

[0046] After each garbage pile in the landfill is treated by the first garbage treatment step and the second garbage treatment step, and the stockpile of garbage is basically eliminated, further ecological restoration treatment can be performed to make the corresponding area meet the preset use standard.

[0047] The ecological restoration treatment can be set according to the actual needs (for example, the future land development and utilization plan of the landfill) to meet the requirements of the preset use standard. For example, the site can be ecologically restored according to the requirements of "Technical Requirements for Utilization of Stabilized Landfill Sites of Domestic Waste" (GB / T25179) to meet the technical requirements of medium and high intensity utilization.

[0048] The repair and management method provided in the embodiments of the present application classifies and processes the garbage pile, and finally restores the land value after the harmless removal and ecological restoration of the domestic waste landfill.

[0049] In one aspect, for a waste pile with a high degree of stabilization, a sorting workshop is built in a vacant land around the landfill, and the stock waste is further screened and classified for harmless, resourceful and energyful utilization.

[0050] In another aspect, for a waste pile with a low degree of stabilization, in-situ aerobic stabilization is performed, and technical indexes such as methane and odor emissions and pile stability are monitored to reach the mining conditions (i.e., the degree of stabilization reaches the preset standard), and the stock waste in the landfill is mined, screened and resourcefully utilized.

[0051] The following takes the second waste treatment step as an example to describe in detail the specific process of mining and treating the stock waste of the waste pile and the technical effects that can be achieved. The second waste treatment step described in one or more embodiments can be combined arbitrarily to achieve the combination of technical effects.

[0052] It should be noted that the first waste treatment step can be in the same manner as the second waste treatment step described in one or more embodiments and achieve similar waste treatment effects. To avoid repeated description, the first waste treatment step will not be described in detail below.

[0053] FIG. 2 is a schematic diagram of the second waste treatment step provided by the embodiments of the present application. As shown in FIG. 2, the second waste treatment step includes:

[0054] S410, under the protection of a preset at least one protection measure, mining the waste pile.

[0055] The "protection measure" refers to a series of measures taken to avoid the environmental factors generated in the process of mining the waste pile.

[0056] Specifically, the protection measure can include setting up a three-dimensional deodorization system to remove the odor in the process of mining the waste pile. The three-dimensional deodorization system includes an air-filled greenhouse surrounding the waste pile, an air deodorization device on the mining operation surface, and a spray deodorization device located on the periphery of the air-filled greenhouse.

[0057] In other embodiments, the protection measure can also include taking noise reduction, sound insulation and shock absorption measures for equipment with high noise, using transport vehicles with low operating noise to reduce noise, and taking temporary blocking, drainage measures, covering and other water and soil conservation prevention measures in building construction areas, roads and areas that need to be hardened, temporary occupied areas, etc.

[0058] S430, screening and treating the stock waste obtained by mining the waste pile to form a plurality of different types of waste.

[0059] The "screening treatment" refers to sorting the excavated garbage according to the size by one or more sorting devices, so as to form garbage of different types and sizes for subsequent processing.

[0060] Preferably, the screening treatment can be carried out in a simple closed plant to avoid dust and odor emission, and can also meet the low water content requirement of the screening system during garbage treatment. The specific screening system used can be configured according to actual needs (for example, screening scale, working system, and process equipment), and is not limited herein.

[0061] S450, according to the characteristics of different types of garbage, a preset resource utilization treatment is performed to form various renewable resources.

[0062] The "resource utilization treatment" refers to converting garbage into renewable resources that can be recycled and utilized by corresponding treatment according to different characteristics of the garbage. Different types of garbage can be converted into different renewable resources according to their characteristics.

[0063] For example, the sorted construction garbage (for example, brick and stone tiles) can be mixed with humus soil to produce new building materials and fired haydite, or used to manufacture water permeable bricks for urban roads or used for on-site backfilling of garbage landfills after harmless treatment. The sorted light materials such as waste plastics and silt can be recycled by cracking process.

[0064] In some embodiments, for the leachate generated during the excavation of the garbage pile, the second garbage treatment further includes an additional leachate treatment step. Please continue to refer to FIG. 2, the second garbage treatment further includes:

[0065] S420, collecting the leachate generated during the excavation of the garbage pile by a leachate collection system.

[0066] S440, using a preset sewage treatment process to treat the leachate.

[0067] The preset sewage treatment process specifically includes: first, pretreating the collected leachate to form homogeneous wastewater to be treated. Then, treating the wastewater to be treated by a reverse osmosis concentration system to obtain wastewater meeting the discharge standard. Finally, treating the concentrated liquid generated by the reverse osmosis concentration system by evaporation crystallization technology.

[0068] In some embodiments, FIG. 3 is a schematic diagram of the sewage treatment process provided by the embodiments of the present application. As shown in FIG. 3, the sewage treatment process can specifically include the following steps:

[0069] S441, the leachate collected is temporarily stored in the conditioning tank 401. The conditioning tank 401 functions to adjust the water quality and quantity, remove suspended solids, and adjust the wastewater flow rate, etc.

[0070] S442, the leachate output from the conditioning tank 401 is subjected to one or more pre-treatment operations by the pre-treatment module 402. The pre-treatment operations include solid separation (e.g., preliminary separation and removal of large-particle solids, suspended solids, and precipitates in the wastewater), water quality adjustment (e.g., adjustment of pH value, removal of part of the organic matter in the wastewater, etc.), and other operations.

[0071] S443, the wastewater to be treated is subjected to the two-stage DTRO treatment system 403, forming a first effluent and a first concentrated liquid. The first concentrated liquid is stored in the concentrated water tank 404.

[0072] S444, the first concentrated liquid stored in the concentrated water tank 404 is subjected to the two-stage HPRO treatment system 405, forming a second effluent and a second concentrated liquid.

[0073] S445, the first effluent and the second effluent are collected in the degassing tower 406 for degassing treatment, obtaining an effluent with free carbon dioxide removed.

[0074] S446, the effluent with free carbon dioxide removed is subjected to treatment by the ion exchanger 407, obtaining wastewater meeting discharge standards.

[0075] S447, the second concentrated liquid is subjected to evaporation treatment by the evaporator 408, forming crystalline salt and condensate.

[0076] S448, the condensate is returned to the input end of the two-stage HPRO treatment system 405 for re-RO treatment.

[0077] S449, the crystalline salt is subjected to solidification and drying treatment, forming tailings and being transported to the landfill site 406 by a transport vehicle for backfilling.

[0078] In some embodiments, FIG. 4 is a schematic diagram of the screening treatment provided by the embodiments of the present application. As shown in FIG. 4, the screening treatment can include the following steps:

[0079] S431, the stockpile of garbage excavated from the garbage pile is placed in the sunning area for drying.

[0080] The leachate generated in the sunning area is associated with the above-mentioned step S420, the leachate generated during the sunning and drying process is collected by the leachate collection system and further provided to the sewage treatment process shown in FIG. 3 for treatment.

[0081] Specifically, the stockpile of waste obtained during excavation can be first measured by the measuring area to determine the volume weight, and then moved to the drying area for drying and airing, so as to realize accurate control and adjustment of the excavation progress.

[0082] In addition, the area of the drying area can be set according to the actual needs. For example, it is set according to the daily processing of the stockpile of waste. The time required for drying and airing can also be set according to the actual needs. For example, it is set to 2-7 days.

[0083] In some embodiments, in order to ensure the collection effect of the leachate, the drying area can be properly set and equipped with suitable and matched equipment. As shown in FIG. 5, the collection equipment can include a drying area 501, a leachate drainage ditch 502, and a surface water drainage ditch 503.

[0084] The leachate drainage ditch 502 is arranged at the outer periphery of the drying area 501 for collecting and guiding the leachate. The size is 0.3m×0.3m, and a steel grating cover plate is arranged on the upper surface. The drying area 501 is a hardened concrete ground and is provided with a slope of 3‰ to facilitate the flow of leachate to the leachate drainage ditch 502 at the outer periphery under the action of gravity. The surface water drainage ditch 503 is arranged at the periphery of the leachate drainage ditch 502 and can be used to guide and drain the rainwater collected in the drying area and its periphery.

[0085] Preferably, the drying area 501 can be equipped with a HDPE double-surface geomembrane with a thickness of 0.75mm. During rainfall, the double-surface geomembrane is temporarily covered on the drying area 501 and the leachate drainage ditch 502, so as to control the generation and pollution of the leachate, reduce the influence of rainwater on the waste pile, and protect the environment from the adverse effects that may be caused by the repair and treatment of the waste landfill.

[0086] S432, the stockpile of waste after drying and airing is transported to the first vibrating screen for sorting, and the brick and stone blocks with a size greater than the preset first standard are sorted from the stockpile of waste.

[0087] S433, the remaining stockpile of waste after the first vibrating screen sorting is sorted by a magnetic separator to separate the metal therefrom.

[0088] S434, the remaining stockpile of waste after the metal is separated is sorted by a plurality of drum screens and air separators according to a preset sorting mode to form humus soil, a plurality of brick and stone blocks with different sizes, and light materials.

[0089] Specifically, the above step S434 can use a three-stage screening method to further separate three different sizes of brick and stone blocks from the remaining stockpile of waste in step S433 by using three different size screening devices. Please continue to refer to FIG. 4, which specifically includes:

[0090] S4341. The remaining waste after metal separation is passed through the first drum screen for further separation, forming oversize material larger than the second standard and undersize material smaller than the second standard.

[0091] S4342. The material on the sieve with a size larger than the second standard is screened by the first air separator to separate it into bricks, tiles and lightweight materials with a size between the second standard and the first standard.

[0092] S4343. The undersize material with a size smaller than the second standard is sorted by the second drum screen to form the oversize material with a size larger than the third standard and the undersize material with a size smaller than the third standard.

[0093] S4344. The material on the sieve with a size larger than the third standard is screened by the second air separator to separate it into bricks, tiles and lightweight materials with a size between the third and second standards.

[0094] S4345. The undersize material smaller than the third standard is separated by the third drum screen to form the oversize material larger than the fourth standard and the humus soil smaller than the fourth standard.

[0095] S4346. The material on the sieve with a size larger than the fourth standard is screened by the second air separator to separate it into bricks, tiles and lightweight materials with a size between the fourth and third standards.

[0096] Therefore, through the above series of steps, the dried stock of waste can be further sorted into: humus, bricks and tiles larger than the first standard, bricks and tiles between the second and first standards, bricks and tiles between the third and second standards, bricks and tiles between the fourth and third standards, and lightweight materials.

[0097] Specifically, the first standard is 200mm, the second standard is 70mm, the third standard is 40mm, and the fourth standard is 10mm.

[0098] In some embodiments, the humus soil separated from landfills is rich in organic matter, and also has relatively high levels of SiO2, Al2O3, and other components. Based on these characteristics, a corresponding integrated building materials system can be used to co-process humus soil, construction waste, and solid waste such as waste shale and sludge to produce building materials (sintered bricks, non-fired bricks) and fired ceramsite.

[0099] In addition, the resource utilization of the light materials such as plastics in the landfill stockpile is affected by the high impurity content of the raw materials, and the continuous low-temperature cracking treatment can be used to convert the low-quality waste plastics into fuel oil, combustible gas and carbon black. The fuel oil and combustible gas can be stored or sold, and the carbon black is relatively stable and easy to store, and can be used as general fuel.

[0100] Preferably, the pyrolysis products (e.g., combustible gas and carbon black) can be further used as a heat source in the humus soil firing process described above, reducing or not relying on external energy sources.

[0101] The repair management method provided by the embodiments of the present application processes the landfill stockpile nearby to form resource utilization, and after the sorting treatment, the humus soil obtained by sorting is made into new building materials (sintered bricks) or sintered into ceramsite (used for landscaping or building filler); and the light materials (waste plastics) are low-temperature cracked into oil, gas and carbon black, and further used as energy in the resource production process of humus soil, thereby greatly reducing the transportation time cost of humus soil and reducing the operation cost, and obtaining better environmental, social and economic benefits.

[0102] In summary, the repair management method provided by the embodiments of the present application can significantly improve the resource utilization level of the project through the resource utilization of the stockpile. On the one hand, the economic benefits of the resource utilization of humus soil are improved. The humus soil is used for the supply of building materials and landscaping use required by the surrounding development by local resource utilization, especially ceramsite, which has reached harmless after high-temperature sintering and can be sold to the market, increasing the economic benefits of the project. On the other hand, the economic benefits of the resource utilization of the light sieve material are improved. The light sieve material is used to produce fuel oil and combustible gas and carbon black by thermal cracking process, the fuel oil can be directly sold, and the combustible gas and carbon black are used as heat source fuel for deep processing of humus soil, reducing the use of external energy and increasing the project income.

[0103] Moreover, the entire repair management process follows the principles of "harmless, reduction and resource utilization", so that the excavation and disposal of the landfill site truly forms two cores of "technical closed loop" and "economic closed loop", without the need to transport humus soil to other places for landfill, which can completely solve the environmental safety hidden trouble problem of the landfill site, effectively control the influence of garbage on the ecological environment, and greatly reduce the influence of historical stockpile on the surrounding area of the landfill site. Through the resource and energy utilization of the stockpile, the carbon emission of the landfill site can be effectively reduced, which makes a positive contribution to the goal of reducing pollution and carbon.

[0104] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application, but not to limit them; under the idea of the present application, the technical features in the above examples or different embodiments can also be combined, the steps can be implemented in any order, and there are many other changes of different aspects of the present application as described above, which are not provided in details for simplicity; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for remediation of a landfill, characterized in that, The method comprises the following steps: determining the degree of stabilization of each garbage pile in the landfill; when the degree of stabilization of the garbage pile meets the preset standard, performing a preset first garbage treatment step; when the degree of stabilization of the garbage pile does not meet the preset standard, performing aerobic stabilization pretreatment on the garbage pile by introducing oxygen and microbial inoculum into the garbage pile; and after the aerobic stabilization pretreatment is completed, performing a preset second garbage treatment step; the landfill where the garbage is treated by the first garbage treatment step and / or the second garbage treatment step is subjected to ecological restoration treatment so that the restored landfill meets the preset use standard; wherein the first garbage treatment step is performed in the adjacent area of the garbage pile; and the second garbage treatment step is performed in the area where the garbage pile is located. The second garbage treatment step comprises:

2. The method of claim 1, wherein, excavating the garbage pile under the protection of at least one preset protection measure; screening the stockpiled garbage obtained by excavating the garbage pile to form multiple types of garbage; according to the characteristics of the different types of garbage, performing a preset resource utilization treatment to form multiple renewable resources. The steps of the aerobic stabilization pretreatment specifically comprise:

3. The method of claim 1, wherein, introducing oxygen into the garbage pile through an air injection system and adding facultative microbial inoculum for stabilization treatment; and extracting air inside the garbage pile through an air extraction system; during the stabilization treatment, multiple different treatment indicators are monitored to determine the state of the garbage pile, and the air injection system and the air extraction system are controlled according to the state of the garbage pile; wherein the treatment indicators include pressure, flow rate, temperature, humidity, gas composition, and pile settlement; the air injection wells of the air injection system are arranged in an equidistant quincunx or cross shape, and the air extraction system is provided with an air filtration device for filtering air from inside the garbage pile. The protection measures include:

4. The method of claim 2, wherein, setting up a three-dimensional deodorization system to remove odor during the excavation of the garbage pile; wherein the three-dimensional deodorization system comprises an air-filled greenhouse surrounding the garbage pile, an air deodorization device on the excavation surface, and a spray deodorization device located on the periphery of the air-filled greenhouse. The second garbage treatment step further comprises:

5. The method of claim 1, wherein, collecting leachate generated during the excavation of the garbage pile through a leachate collection system; and treating the leachate using a preset sewage treatment process; wherein the preset sewage treatment process specifically comprises: pretreating the collected leachate to form homogeneous wastewater to be treated; treating the wastewater to be treated through a reverse osmosis concentration system to obtain wastewater meeting discharge standards; treating the concentrated liquid generated by the reverse osmosis concentration system through evaporation crystallization technology. The step of treating the wastewater to be treated through the reverse osmosis concentration system specifically comprises:

6. The method of claim 5, wherein, passing the wastewater to be treated through a two-stage DTRO treatment system to form first effluent and first concentrated liquid; storing the first concentrated liquid in a concentrated water tank; ​ The first concentrated liquid stored in the concentrated water tank is treated by a two-stage HPRO treatment system to form second effluent and second concentrated liquid; The first effluent and the second effluent are collected into a degassing tower for degassing treatment to obtain effluent after removal of free carbon dioxide; The effluent after removal of free carbon dioxide is treated by an ion exchanger to obtain the wastewater meeting the discharge standard; The step of treating the concentrated liquid generated by the reverse osmosis concentration system by evaporation crystallization technology specifically comprises: The second concentrated liquid is treated by an evaporator to form crystalline salt and condensate; The condensate is returned to the input end of the two-stage HPRO treatment system for reverse osmosis treatment again; The crystalline salt is solidified and dried to form tailings; the tailings can be used for backfilling of the landfill site.

7. The method of claim 5, wherein, The step of screening the inventory garbage obtained by excavating the garbage pile specifically comprises: The inventory garbage excavated from the garbage pile is placed in a drying area for drying, and leachate generated in the drying area is collected by the leachate collector; The inventory garbage after drying is transported to a first vibrating screen for sorting, and brick and stone blocks with a size greater than a first preset standard are sorted from the inventory garbage; The remaining inventory garbage after the first vibrating screen sorting is sorted by a magnetic separator to sort out metal; The remaining inventory garbage after sorting out metal is sorted by a plurality of drum screens and air separators according to a preset sorting mode to form humus, a plurality of brick and stone blocks of different sizes, and light materials.

8. The method of claim 7, wherein, The drying area is a hardened concrete ground with a slope of 3‰; A leachate drainage ditch is arranged on the outer periphery of the drying area, and a steel grating cover plate is arranged on the leachate drainage ditch; and a surface water drainage ditch is further arranged on the outer periphery of the leachate drainage ditch; During rainfall, the drying area is further covered with a removable double-surface geomembrane; the double-surface geomembrane has a thickness of 0.75 mm; and the double-surface geomembrane is removed when it is not raining.

9. The method of claim 7, wherein, The step of sorting the remaining inventory garbage after sorting out metal by a plurality of drum screens and air separators according to a preset sorting mode to form humus, brick and stone blocks with a size greater than a second standard, and light materials specifically comprises: The remaining inventory garbage after sorting out metal is sorted by a first drum screen to form oversize material with a size greater than the second standard and undersize material with a size less than the second standard; The oversize material with a size greater than the second standard is sorted by a first air separator to form brick and stone blocks with a size between the second standard and the first standard and light materials; The undersize material with a size less than the second standard is sorted by a second drum screen to form oversize material with a size greater than a third standard and undersize material with a size less than the third standard; The oversize material with a size greater than the third standard is sorted by a second air separator to form brick and stone blocks with a size between the third standard and the second standard and light materials; The undersize material with a size less than the third standard is sorted by a third drum screen to form oversize material with a size greater than a fourth standard and humus with a size less than the fourth standard; The oversize larger than the fourth standard is screened by a second air separator to separate the brick and stone tile pieces and light materials having sizes between the fourth standard and the third standard.

10. The method of claim 9, wherein, The step of performing a preset resource utilization treatment according to the characteristics of the different types of garbage to form various renewable resources specifically includes: The humus soil is subjected to a firing treatment to form a building material or a ceramsite; The light materials are subjected to a cracking treatment to obtain fuel oil, combustible gas and carbon black.

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