Treatment method and treatment system for incineration residue

Abstract

The invention relates to a disposal method for incineration residues and a disposal system for incineration residues, and provides a technology capable of promoting decomposition of incineration residue components by microorganisms and shortening the stabilization period in the case of landfill and final disposal of incineration residues. The disposal method for the incineration residue comprises the steps of: landfill of the incineration residue in a landfill section provided in a landfill land; a step of providing a sheet material for covering the landfill surface of the incineration residue in the landfill section; and a step for supplying water to the lower part of the sheet by using a watering device to maintain the water content in the landfill located below the sheet at 5-30%. The water content may be maintained at 10-25% by the supply of water using the watering device.

Description

Technical Field

[0001] This invention relates to a technology for landfilling and final disposal of incineration residues. Background Technology

[0002] The waste ash (main ash from incineration) and fly ash (fly ash from incineration) from the incineration facility are buried in a semi-aerobic final disposal site and undergo a stabilization period of about 30 years, thereby reducing the concentration of organic matter, inorganic salts, heavy metals and other substances in the incineration residue to low levels.

[0003] Patent Document 1 discloses a technique for pre-treating incineration residue before landfilling it to a final disposal site. This pre-treatment involves manually cleaning the incineration residue before landfilling. During the cleaning process, aeration and water spraying are performed simultaneously to improve cleaning efficiency. The cleaning continues until the total organic carbon (TOC) concentration in the water leached from the incineration residue layer is below a baseline concentration. After pre-treatment, the incineration residue is landfilled at the final disposal site. The landfilled incineration residue is sprayed with water at a rate of 2 mm / day.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2006-281006

[0007] Patent Document 1 shortens the stabilization period by reducing the concentration of incineration residue components such as organic matter and heavy metals to a certain level. However, considering that the stabilization period implies a slowdown in gas production and heat generation caused by microbial reactions within the landfill, it is clear that the microorganisms surrounding the incineration residue components are what contribute to shortening the stabilization period after landfilling. In this respect, there is room for improvement in the technology of Patent Document 1, which completely disregards the function of microorganisms. Summary of the Invention

[0008] One object of the present invention is to provide a technique that can promote the decomposition of incineration residue components by microorganisms and shorten the stabilization period in the case of final disposal of incineration residue in landfill.

[0009] The inventors analyzed numerous microorganisms present in landfills and identified Alkalibacterium and Pseudomonas species as strong candidates for microorganisms capable of decomposing components of incineration residues. As a result, the inventors discovered that by maintaining the incineration residues after landfilling in an environment where these strong candidates can be activated, the stabilization period can be shortened. This invention is based on this insight.

[0010] The first aspect of this invention is a method for disposing of incineration residue, which has the following characteristics.

[0011] The method includes the steps of: burying incineration residue into a landfill section located in a landfill; providing a sheet to cover the landfill surface of the incineration residue in the landfill section; and supplying water to the area below the sheet using a sprinkler system to maintain the moisture content of the landfill below the sheet at 5-30%.

[0012] In the first viewpoint, the moisture content can also be maintained at 10-25% by using the water supply from the sprinkler device.

[0013] The second aspect of the present invention is a system for disposing of incineration residue, which has the following characteristics.

[0014] The system comprises: a sheet for covering the landfill surface of incineration residue in a landfill section located in a landfill; and a water spraying device for supplying water to the area below the sheet in a manner that maintains the moisture content of the landfill interior below the sheet at 5-30%.

[0015] In a second viewpoint, the watering device may supply water in a manner that maintains the moisture content at 10-25%.

[0016] Invention Effects

[0017] According to the present invention, by covering the landfill surface of incineration residue with sheets and maintaining the moisture content inside the landfill at 5-20%, it is possible to protect microorganisms of the genera *Alcaligenes* and *Pseudomonas* and to regulate the humidity inside the landfill. Therefore, it is possible to maintain an environment within the landfill where these microorganisms can be activated, thereby shortening the stabilization period. Attached Figure Description

[0018] Figure 1 This is a block diagram illustrating a structural example of an incineration residue disposal system according to an embodiment.

[0019] Figure 2 This is a conceptual diagram illustrating the first structural example of the final disposal site and the first landfill disposal example of the incineration residue in the final disposal site.

[0020] Figure 3 This is a conceptual diagram illustrating a second structural example of the final disposal site and a second landfill disposal example of the incineration residue in the final disposal site.

[0021] Figure 4 This is a block diagram representing a second structural example of a system for disposing of incineration residue.

[0022] Figure 5 This is a block diagram representing a third structural example of an incineration residue disposal system.

[0023] Explanation of reference numerals in the attached figures

[0024] 10 Final Disposal Site

[0025] Landfill zones 11, 12, and 17

[0026] Groups 13 and 18 of the stone cutting group

[0027] 14 sets of drain pipes

[0028] 15 and 16 sheet

[0029] Sprinkler devices 20, 21, and 22

[0030] 30 Cleaning Device

[0031] 40 water tanks

[0032] Purification devices 50, 51, and 52

[0033] 60 power generation system

[0034] 100, 200, 300 handling systems

[0035] AS incineration residue

[0036] Incineration residue after cleaning of AS-W, AS-W1~AS-W3

[0037] WT1~WT8 water Detailed Implementation

[0038] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Furthermore, common elements in all figures are labeled with the same reference numerals, and repeated descriptions are omitted.

[0039] 1. System Structure Example

[0040] Figure 1 This is a block diagram illustrating a structural example of an incineration residue disposal system according to an embodiment. Figure 1 In the example shown, the treatment system 100 includes a final treatment area 10, a sprinkler system 20, a cleaning system 30, a water tank 40, a purification system 50, and a power generation system 60. The final treatment area 10 is connected to the purification system 50, the purification system 50 to the water tank 40, the water tank 40 to the sprinkler system 20, and the water tank 40 to the cleaning system 30 via piping. Furthermore, the power generation system 60 is connected to the sprinkler system 20, the cleaning system 30, and the purification system 50 via power lines.

[0041] Final disposal site 10 is an outdoor (open) facility for landfilling incineration residue AS. Final disposal site 10 is located within a landfill. Final disposal site 10 typically includes groundwater collection and drainage facilities, a groundwater sump, a leachate collection and drainage facility, a leachate sump, and an exhaust system. The groundwater collection and drainage facilities are used to collect and rapidly discharge water or runoff generated in the lower part of final disposal site 10. The groundwater sump is used for monitoring the quality of groundwater. The leachate collection and drainage facilities are used to rapidly collect water WT1 spilled in the landfill. The leachate sump is used to transport water WT4 collected in the leachate collection and drainage facilities to the purification unit 50. The exhaust system is used to rapidly exhaust gases generated in the landfill and supply air into the landfill.

[0042] The sprinkler system 20 is a device for spraying water WT1 from the water tank 40 onto the landfill. The sprinkler system 20 is, for example, a sprinkler array arranged in a mesh on the outermost surface of the landfill. The spray volume of water WT1 from the sprinkler system 20 is appropriately adjusted, for example, to ensure that the moisture content within the landfill converges to a desired range (e.g., 5-30%, preferably 10-25%, more preferably 10-15%). Here, the moisture content can be the average of values ​​directly measured at multiple locations within the landfill, or it can be a value estimated based on the amount of leachate from the landfill. In the latter case, the amount of leachate is measured in a leachate collection pit. Therefore, by pre-determining the relationship between the daily leachate volume and the moisture content, the moisture content can be estimated based on the amount of leachate measured in the collection pit.

[0043] The cleaning device 30 is used to wash the incineration residue AS (bottom ash, fly ash, etc. discarded from the incineration facility) with water before landfilling. Examples of cleaning devices 30 include mechanical cleaning devices (e.g., spiral type, jet type) and tank cleaning devices (washing by immersing the incineration residue AS in a water tank). Water washing can be performed using water WT2 in water tank 40. By washing the incineration residue AS with water before landfilling, the treatment cost of leachate (i.e., the construction cost of purification device 50 and the power consumption) can be reduced compared to landfilling the incineration residue AS in an uncleaned state. The water-washed incineration residue AS-W is transported to the final disposal site 10 by a mobile vehicle such as a truck. On the other hand, the water WT3 after water washing is sent to purification device 50.

[0044] Water tank 40 is a tank for storing water used in the treatment system 100. Multiple water tanks 40 may also be provided. Water WT5 treated by the purification device 50 is stored in water tank 40. Water collected from groundwater collection and drainage facilities (or groundwater sump) and tap water may also be stored in water tank 40.

[0045] Purification unit 50 is a device that simultaneously purifies the effluent (water WT3) from cleaning unit 30 and the effluent (water WT4) from final treatment plant 10. In water WT3, approximately 30-100 mg / L of ammonium nitrogen (NH4-N) dissolves along with organic matter (BOD, COD). Therefore, in purification unit 50, a biological denitrification treatment, practical for leachate treatment, is performed. Here, in a conventional system of nitrification, denitrification, and re-degassing, the electricity consumption of the air supply required for nitrification is high. In addition, the GHG emissions (CO2 equivalent emissions) generated by the addition of organic carbon source (methanol) required for denitrification are not negligible. Therefore, in purification unit 50, compared with conventional aerobic / anaerobic treatment, a denitrification treatment with low electricity consumption, such as anaerobic ammonia oxidation (anamox process), is preferred, as it does not require the addition of organic carbon source (methanol), thus achieving decarbonization.

[0046] The power generation system 60 is a system that uses natural energy to generate electricity for the disposal system 100. The power generation system 60 is, for example, a solar power generation and energy storage system installed in a portion of the landfill site. Typically, the solar power generation and energy storage system includes power conversion devices such as solar panels and inverters, as well as batteries to store the electricity generated by the solar panels. At least the sprinkler system 20, the cleaning system 30, and the purification system 50 require electricity to operate; therefore, by providing the power required for the operation of these devices by the power generation system 60, the operating costs of the disposal system 100 can be reduced.

[0047] 2. Structural examples of final disposal sites and examples of incineration residue disposal.

[0048] 2-1. The first example

[0049] Figure 2 This is a conceptual diagram illustrating a first structural example of the final disposal site 10 and a first landfill disposal example of the incineration residue AS-W in the final disposal site 10. Figure 2 A cross-sectional schematic diagram of the final disposal site 10 is depicted. Figure 2 In the example shown, landfill sections 11 and 12 are formed in the final disposal site 10. Landfill sections 11 and 12 are separated by a rock-cutting group 13. In addition to separating the landfill sections, the rock-cutting group 13 also functions to protect the collection and drainage pipe 14 of leachate from the final disposal site 10. Furthermore, the collection and drainage pipe 14 forms part of the aforementioned leachate collection and drainage facility.

[0050] Incineration residue AS-W1 is disposed of in landfill section 11, and incineration residue AS-W2 is disposed of in landfill section 12. Both incineration residue AS-W1 and AS-W2 are examples of the aforementioned incineration residue AS-W. A movable sprinkler system 21 is installed above incineration residue AS-W1, and a movable sprinkler system 22 is installed above incineration residue AS-W2. Sprinkler systems 21 and 22 are examples of the aforementioned sprinkler system 20.

[0051] exist Figure 2 In the example shown, a sheet 15 is also provided above the sprinkler device 21, and a sheet 16 is provided above the sprinkler device 22. Sheets 15 and 16 are provided in such a way that they respectively cover the surfaces of the incineration residues AS-W1 and AS-W2. Sheets 15 and 16 are at least waterproof and breathable. By making sheets 15 and 16 waterproof, rainwater infiltration beneath these sheets can be prevented. By making sheets 15 and 16 breathable, gases, heat, and water vapor generated beneath these sheets can be released into the atmosphere.

[0052] exist Figure 2 The example shown considers the case of filling new incineration residue AS-W (AS-W3) into landfill zone 17 (planned landfill zone) above landfill zone 11. In this case, firstly, the sheet 15 and the sprinkler system 21 (STEP1) installed above the incineration residue AS-W1 are temporarily removed. Then, a stone cutting group 18 (STEP1) is installed above the stone cutting group 13. In addition, a space is formed in the upper right part of the stone cutting group 13 to ensure workability above landfill zone 12. When installing the stone cutting group 18, a collection and drainage pipe for leachate can also be installed above the stone cutting group 13.

[0053] Next, incineration residue AS-W3 (STEP2) is placed into landfill section 17. Similar to incineration residues AS-W1 and AS-W2, incineration residue AS-W3 is an example of the aforementioned incineration residue AS-W. Specifically, regarding the landfilling of incineration residue AS-W3, after it is placed into landfill section 17, it is spread out to a specified thickness and rolled. To promote microbial decomposition of the incineration residue components and ensure horizontal permeability of the incineration residue layer, incineration residue AS-W3 preferably includes an intermediate cover layer of approximately 30 cm.

[0054] Next, a final cover layer of approximately 100 cm is placed on the landfill surface of the incineration residue AS-W3, and then a water sprinkler system 21 is installed on top of it (STEP3). Additionally, sheet material 15 is placed on top of the water sprinkler system 21 to cover the landfill surface (STEP3). After the above procedures, the incineration residue AS-W3 is landfilled into landfill section 17.

[0055] 2-2. Second example

[0056] Figure 3 This is a conceptual diagram illustrating a second structural example of final disposal site 10 and a second landfill disposal example of incineration residue AS-W in final disposal site 10. Figure 2 Similarly, Figure 3 The diagram depicts a cross-sectional schematic of the final disposal site 10.

[0057] exist Figure 3 In the example shown, sheet 15 is positioned above sprinkler device 21, and sheet 16 is positioned above sprinkler device 22. Up to this point, with... Figure 2 The example shown is the same. In Figure 3 In the example shown, a movable solar panel 61 is also provided above sheet 15, and a movable solar panel 62 is provided above sheet 16. Solar panels 61 and 62 are equivalent to the structure of the solar panels included in the system when the power generation system 60 is composed of a solar power generation and energy storage system.

[0058] and Figure 2 Similarly, in the example shown, Figure 3 The example shown considers the case of filling new incineration residue AS-W (AS-W3) into landfill zone 17 (planned landfill zone). In this case, firstly, the sheet 15, sprinkler system 21, and solar panel 61 (STEP1) installed above the incineration residue AS-W1 are temporarily removed. Then, the rock cutting group 18 (STEP1) is installed above the rock cutting group 13.

[0059] Next, incineration residue AS-W3 (STEP2) is landfilled in landfill section 17. This process is related to... Figure 2 The example shown is the same. Next, a final cover layer is applied to the landfill surface of the incineration residue AS-W3 after landfilling, and then a sprinkler system 21 and sheet 15 are applied on top of it to cover the landfill surface (STEP3). In addition, a solar panel 61 is applied on top of the sheet 15. After the above procedures, the incineration residue AS-W3 is landfilled into the landfill section 17.

[0060] 3. Effects

[0061] As described above, the inventors identified microorganisms of the genus *Alkalibacterium* (e.g., *Alkalibacterium olivapovliticus*) and microorganisms of the genus *Pseudomonas* (e.g., *Pseudomonas spinosa*) as strong candidates for microorganisms capable of decomposing the components of incineration residues AS-W. Therefore, these microorganisms present in the final cover layer or similar material provided on the landfill surface of the incineration residue AS-W decompose the incineration residue components of the AS-W, thereby stabilizing the incineration residue AS-W.

[0062] In particular, according to the embodiment, the incineration residue AS-W is covered with sheets such as sheets 15 and 16 that are at least waterproof and breathable, and the moisture content of the incineration residue AS-W is adjusted to converge to a desired range using water WT1 sprayed from the water spraying device 20. Therefore, a favorable environment for the activation of the aforementioned microorganisms is maintained. Thus, microbial decomposition of the incineration residue components of the incineration residue AS-W can be promoted, shortening the stabilization period. By shortening the stabilization period, decarbonization can also be achieved by reducing CO2 emissions associated with the operation of the incineration residue disposal system.

[0063] 4. Other structural examples of the system

[0064] The application of this invention is not limited to Figure 1 The disposal system 100 described in the text. Figure 4 This is a block diagram representing a second structural example of a system for disposing of incineration residue. Figure 4 In the example shown, water WT6 is supplied from the final disposal site 10 to the water tank 40. Water WT6 is specifically rainwater. The supply of water WT6 to the water tank 40 can be achieved, for example, by collecting rainwater that flows naturally from sheets (sheets 15, 16) disposed on the landfill surface of the final disposal site 10.

[0065] Figure 5 This is a block diagram representing a third structural example of an incineration residue disposal system. Figure 5 In the example shown, purification devices 51 and 52 are provided. Purification device 51 is a device for treating the effluent (water WT3) from the cleaning device 30. Purification device 52 is a device for treating the effluent (water WT4) from the final disposal site 10. Purification device 51 is connected to the cleaning device 30, purification device 51 is connected to the water tank 40, purification device 52 is connected to the final disposal site 10, and purification device 52 is connected to the water tank 40 via piping. In addition, power generation system 60 is connected to purification device 51, and power generation system 60 is connected to purification device 52 via power transmission lines.

[0066] and Figure 1The examples shown are different, in Figure 5 In the example shown, the effluent (WT3) from the cleaning unit 30 and the effluent (WT4) from the final treatment site 10 are treated separately by two purification units. The treatment in purification unit 51 can be a low-power denitrification process such as anaerobic ammonia oxidation, which does not require the addition of organic carbon sources, or it can be a conventional aerobic treatment. The treatment in purification unit 52 can be a low-power denitrification process such as anaerobic ammonia oxidation, which does not require the addition of organic carbon sources, or it can be a conventional anaerobic treatment.

[0067] exist Figure 5 In the example shown, water WT7, which has been treated by purification device 51, and water WT8, which has been treated by purification device 52, are respectively delivered to water tank 40.

Claims

1. A method for disposing of incineration residue, characterized in that, include: The steps of burying incineration residues in landfill zones located within a landfill site; The step of setting up a sheet to cover the landfill surface of the incineration residue in the landfill zone; as well as The step of using a sprinkler system to supply water to the area below the sheet to maintain the moisture content of the landfill below the sheet at 5-30%.

2. The method for disposing of incineration residue according to claim 1, characterized in that, It also includes the step of washing the incineration residue with water before burying it in the landfill zone.

3. The method for disposing of incineration residue according to claim 2, characterized in that, Also includes: The step of purifying the leachate from the landfill section and the washing water after washing the incineration residue using a purification device; as well as The step of supplying the purified water to the water tank. The water supply from the sprinkler system is made using water from the water tank.

4. The method for disposing of incineration residue according to claim 1 or 2, characterized in that, The water supply from the sprinkler system is made using water from a tank connected to the sprinkler system that is capable of storing rainwater.

5. The method for disposing of incineration residue according to claim 1 or 2, characterized in that, The moisture content is maintained at 10-25% by using the water supply from the sprinkler device.

6. The method for disposing of incineration residue according to claim 1, characterized in that, Also includes: The step of mounting a movable solar power generation panel on top of the sheet; as well as The steps of using the electricity generated by the solar panel to operate the sprinkler system.

7. The method for disposing of incineration residue according to claim 3, characterized in that, Also includes: The step of mounting a movable solar power generation panel on top of the sheet; as well as The steps of using the electricity generated by the solar panel to operate the purification device.

8. The method for disposing of incineration residue according to claim 6 or 7, characterized in that, Also includes: In the case of adding incineration residue to the landfill surface, the step of moving the sheet and the solar panel located in a predetermined landfill section of the added incineration residue. The step of burying additional incineration residue into the predetermined landfill zone after the sheet and the solar panel have been moved; as well as The step of repositioning the sheet and the solar panel above the landfill surface of the additional incineration residue in the predetermined landfill zone.

9. The method for disposing of incineration residue according to claim 1 or 2, characterized in that, The sheet material is waterproof and breathable.

10. A system for disposing of incineration residue, characterized in that, have: Sheets are used to cover the landfill surface of incineration residues in landfill sections located within a landfill site; and A water spraying device supplies water to the area below the sheet in a manner that maintains the moisture content of the landfill below the sheet at 5-30%.

11. The incineration residue disposal system according to claim 10, characterized in that, The watering device supplies water in a manner that maintains the moisture content at 10-25%.

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