JP7245193B2 - Waste landfill disposal method - Google Patents

Description

The present invention relates to a waste landfill treatment facility and a waste landfill treatment method.

Conventionally, some final waste disposal sites in Japan have adopted a bioreactor-type semi-aerobic landfill structure that utilizes the natural purification function and its decomposition mechanism.

Semi-aerobic landfill structures primarily utilize aerobic microbial metabolism to treat waste. That is, the semi-aerobic landfill structure maintains the internal oxygen concentration at such a concentration that the aerobic microorganisms are activated, thereby allowing the aerobic microorganisms to decompose the organic matter contained in the waste.

On the other hand, since the semi-aerobic landfill structure uses the natural purification function, anaerobic microorganisms also exist inside. Therefore, when the oxygen concentration inside decreases, the anaerobic microorganisms are activated, and the organic matter contained in the waste is decomposed by the anaerobic microorganisms. Hydrogen sulfide and methane are produced in this anaerobic microbial decomposition process.

The gaseous components generated by the decomposition process as described above cause a decrease in the oxygen concentration inside the semi-aerobic landfill structure. A decrease in oxygen concentration is not desirable because it inhibits the decomposition process by aerobic microorganisms, and furthermore, by accelerating the decomposition process by anaerobic microorganisms, harmful hydrogen sulfide and combustible methane are generated. I don't like it. Therefore, the semi-aerobic landfill structure preferably has a control function to maintain the semi-aerobic condition.

As a semi-aerobic landfill structure with such a control function, in Patent Document 1,
a container for containing waste;
A water collection piping section arranged along the bottom of the storage section and capable of collecting and discharging leachate seeping from the waste, wherein at least one end of the collection piping section is open to the atmosphere. a water pipe;
A ventilation pipe branched from the water collection pipe and having a plurality of ventilation holes formed in a side wall thereof, the ventilation pipe extending vertically in the waste and having a distal end protruding upward from the waste. a plurality of ventilation pipes arranged in such a manner as to
A portable blower that supplies air from the tip of the ventilation pipe into the pipe,
A waste landfill treatment facility is described in which the portable blower is controlled to supply air when the concentration of hydrogen sulfide discharged from the vent pipe exceeds a standard value.

According to such a waste landfill treatment facility, the leachate is collected by the water collecting pipe portion and discharged from one end of the water collecting pipe portion. Also, a portable blower supplies air into the ventilation pipe, and this air flows into the housing through a plurality of ventilation holes formed in the ventilation pipe. Furthermore, since air is supplied to the ventilation pipe using the concentration of hydrogen sulfide discharged from the ventilation pipe as an index, the air is supplied to the container before the anaerobic property of the container greatly increases. In this way semi-aerobicity can be maintained.

Patent No. 6348999

However, in the waste landfill treatment facility described in Patent Document 1, methane may be generated due to locally increased anaerobicity. Even if air is supplied, there is a problem that generation of methane is difficult to be suppressed.

In view of the above problems, an object of the present invention is to provide a waste landfill treatment facility and a waste landfill treatment method that can relatively easily suppress the generation of methane.

The waste landfill facility for semi-aerobically treating waste according to the present invention includes:
a storage unit that stores the waste;
A water collection piping section arranged along the bottom of the storage section and capable of collecting and discharging leachate seeping from the waste, wherein at least one end of the collection piping section is open to the atmosphere. a water pipe;
A ventilation pipe branched from the water collection pipe and having a plurality of ventilation holes formed in a side wall thereof, the ventilation pipe extending vertically in the waste and having a distal end protruding upward from the waste. a plurality of ventilation pipes arranged in such a manner as to
and a water supply unit for supplying water so as to drop the inside of the ventilation pipe unit.

According to such a configuration, the generation of methane can be relatively easily suppressed by supplying water so as to drop in the ventilation pipe section by the water supply section. The reason why such an effect is produced is that the water is supplied by the water supply part so as to drop in the ventilation pipe part, so that the water is entrained with air and reaches deeper into the ventilation pipe part. To obtain this, it is believed that the air is supplied deeper into the enclosure. As a result, it is thought that the air is supplied even to the portion of the storage unit where the anaerobic property is locally greatly increased, thereby suppressing the generation of methane.

In addition, the waste landfill treatment facility according to the present invention is
A concentration measurement unit may be provided for measuring concentrations of components contained in the gas discharged from the tip of the ventilation pipe.

Here, decomposition heat is generated in the waste decomposition process of microorganisms, and the decomposition heat generates an upward air current inside the ventilation pipe. For this reason, air is induced into the water collection pipe portion from the side of the water collection pipe portion that is open to the atmosphere, and the air is discharged from the tip portion of the ventilation pipe portion through the ventilation pipe portion. In addition, since a plurality of vent holes are formed in the vent pipe, the gas in the housing part flows into the vent pipe. Therefore, by measuring the components of the gas discharged from the tip of the ventilation pipe, the composition of the gas in the housing can be grasped. Therefore, according to such a configuration, the result of measurement by the concentration measuring unit serves as an indicator for determining whether to supply water, so unnecessary supply of water can be reduced and water can be supplied more efficiently.

In addition, the waste landfill treatment facility according to the present invention is
The water supplied by the water supply unit may be the leachate.

According to such a configuration, the water supplied by the water supply unit is leachate, and there is no need to separately prepare water such as groundwater, so the facility can be made more efficient.

As described above, according to the present invention, it is possible to provide a waste landfill treatment facility and a waste landfill treatment method that can relatively easily suppress the generation of methane.

FIG. 1 is a schematic diagram showing a waste landfill facility according to a first embodiment of the present invention. FIG. 2 is an enlarged view of the concentration measuring unit of the waste landfill treatment facility according to the present embodiment. FIG. 3 is a conceptual diagram showing the relationship of various gas concentrations in the waste landfill facility according to this embodiment. FIG. 4 is a schematic diagram showing a waste disposal facility according to the second embodiment. FIG. 5 is a schematic diagram showing a waste disposal facility according to the third embodiment. FIG. 6 shows a schematic view of the waste landfill treatment facility of FIG. 1 and the embodiment as viewed from above. FIG. 7 is a graph showing the results of measuring over time the gas discharged from the ventilation pipe part whose tip is arranged at the position of A in FIG. 6 . FIG. 8 is a graph showing the results of measuring over time the gas discharged from the ventilation pipe part whose tip is arranged at the position of B in FIG. 6 . FIG. 9 is a graph showing the results of measuring over time the gas discharged from the ventilation pipe part whose tip is arranged at the position of C in FIG. 6 . FIG. 10 is a graph showing the results of measuring over time the gas discharged from the ventilation pipe part whose tip is arranged at the position of D in FIG. 6 . FIG. 11 is a graph showing the results of measuring over time the gas discharged from the ventilation pipe part whose tip is arranged at the position of E in FIG. 6 .

Hereinafter, a semi-aerobic waste landfill facility according to a first embodiment of the present invention will be described with reference to the drawings.

As shown in FIGS. 1 and 2, the waste landfill facility 1 according to the present embodiment is arranged along a storage portion 10 for storing waste W and a bottom portion 12 of the storage portion 10, A water collecting pipe portion 20 capable of collecting and discharging leachate L exuded from the waste W, the water collecting pipe portion 20 having a downstream end 22 open to the atmosphere, and a water collecting pipe portion. 20 and has a plurality of vent holes formed in the side wall thereof, the vent pipe portion 30 extending generally vertically in the containing portion 10 in which the waste W is contained, and the tip portion 32 of the waste W and a plurality of ventilation pipe portions 30 arranged to protrude upward from. As a result, in the waste landfill treatment facility 1, air is introduced into the water collection pipe portion 20, the air is supplied to the storage portion 10 through the ventilation pipe portion 30, and the gas in the pipe of the ventilation pipe portion 30 is released from the tip portion 32. configured to be ejected. Furthermore, the waste landfill treatment facility 1 according to the present embodiment includes a receiving pit 40 which receives the leachate L discharged from the water collection piping part 20 and whose upper part is open to the atmosphere, and a receiving pit 40 a seepage water treatment unit 50 for treating the seepage water L; and a concentration measuring unit 80 for measuring the concentration of the component contained in the liquid.

In this embodiment, the surface of the waste layer is formed so as to reach the upper edge 14 of the container 10, but is not limited to this, and the surface of the waste layer is lower than the container 10. position.

Next, the water collecting pipe section 20 will be described in detail with reference to FIG. 6 as well. FIG. 6 is a schematic diagram of the waste landfill treatment facility 1 as seen from above, and in FIG. The water collection pipe section 20 has a main pipe 202 including a downstream end 22 open to the atmosphere, and a plurality of branch pipes 204 branching off from the main pipe 202 . The main pipe 202 of the water collecting pipe portion 20 is arranged along the bottom portion 12 of the housing portion 10 so as to be inclined from the upstream end 28 toward the downstream end 22, and the downstream end 22 is arranged at the lowest position. As a result, the collected leachate L can be discharged from the downstream end 22 open to the atmosphere. The branch pipe 204 of the water collection pipe section 20 has the end connected to the main pipe 202 at the lowest position, and is configured to allow the collected leachate L to flow into the main pipe 202 . The water collection piping part 20 is arranged so that a part including the downstream end 22 extends outside the housing part 10 , and the downstream end 22 is connected to the receiving pit 40 . As described above, since the upper part of the receiving pit 40 is open to the atmosphere, the water collecting pipe section 20 is also open to the atmosphere via the receiving pit 40 .

In this embodiment, the water collection pipe portion 20 has a plurality of holes formed in the upper surface portion, and the seepage water L can be received through the plurality of holes. In addition, the water collection pipe portion 20 can receive the leachate L through the ventilation pipe portion 30 as well.

As indicated by the dashed arrow (lower rightward arrow) in FIG. , from the upstream end 28 toward the downstream end 22 in the water collecting pipe section 20 and is discharged from the downstream end 22 into the receiving pit 40 . In addition, the water collecting pipe portion 20 forms an upper region 26 through which air can flow. As a result, air can flow into the water collecting pipe section 20 via the receiving pit 40, as indicated by the solid line arrow (arrow pointing to the upper left) in FIG. The air that has flowed into the water collecting pipe portion 20 flows into the housing portion 10 through a plurality of vent holes formed in the upper surface portion of the water collecting pipe portion 20 or flows into the ventilation pipe portion 30 .

The water collection piping part 20 preferably has a size that allows the seepage water L to flow through the lower region 24 and the air to flow through the upper region 26 . From this point of view, the diameter of the main pipe 202 of the water collecting pipe section 20 is usually set to 500 to 1000 mm. Also, the diameter of the branch pipe 204 of the water collecting pipe portion 20 is usually set to 75 to 1000 mm.

A part of the water collection piping part 20 may be arranged outside the housing part 10 . For example, the water collecting pipe portion 20 has at least a portion in which a plurality of holes are formed (that is, a portion forming the upper region 26) is arranged in the housing portion 10, and a portion forming the lower region 24 is the housing portion. 10 may be arranged below.

The ventilation pipe portion 30 is arranged to extend substantially vertically from the upper portion of the water collection pipe portion 20 . The ventilation pipe portion 30 is branched from each of the main pipe 202 and the branch pipe 204 of the water collection pipe portion 20 . Further, the ventilation pipe portion 30 is open to the atmosphere by arranging the tip portion 32 above the upper edge 14 of the housing portion 10 . The ventilation pipe part 30 has a plurality of ventilation holes formed in its side wall. As a result, as indicated by the arrows drawn on the side of the ventilation pipe portion 30 in FIG. 1, air or gas such as methane and the leachate L can flow through the plurality of ventilation holes. More specifically, the leachate L exuding from the waste W flows into the vent pipe portion 30 through the plurality of vent holes of the vent pipe portion 30 . In addition, since the heat generated by the decomposition of the organic matter generated in the waste W generates an ascending air current in the ventilation pipe portion 30, the air that rises from the water collection pipe portion 20 and flows into the ventilation pipe portion 30 flows into the ventilation pipe portion 30. Gases such as hydrogen sulfide and methane, which may be generated from the waste W in the storage unit 10, flow into the storage unit 10 through the plurality of ventilation holes of the piping unit 30, and pass through the ventilation pipe through the plurality of ventilation holes. It flows into the interior of portion 30 and exits through tip portion 32 . Note that the ventilation pipe portion 30 may be formed so that a portion thereof disposed in the housing portion 10 extends along the horizontal direction, and water such as seepage water L supplied from a water supply pipe 64 described later is discarded. It is preferably configured to be supplied to an object W.

When the surface of the waste layer is formed at a position lower than the upper edge 14 of the containing portion 10, the tip portion 32 of the vent pipe portion 30 is arranged above the surface of the waste layer, thereby , may be open to the atmosphere. In this case, the ventilation pipe part 30 is designed so that even if the surface of the waste layer becomes higher as the waste W is landfilled, the tip part 32 always protrudes from the waste W. Depending on the size, it is opened to the atmosphere by extending it by extending it by replenishment or the like.

The diameter of the ventilation pipe portion 30 is normally set to 75 to 1000 mm. Also, the length of the ventilation pipe portion 30 is normally set to 20 to 50 m.

The receiving pit 40 accommodates the seepage water L discharged from the water collecting pipe section 20 . The receiving pit 40 has a connection area 42 with the water collecting pipe section 20, a lower area 44 arranged below the connection area 42, and an upper area 46 arranged above the connection area 42. there is

It is preferable that the lower area 44 can accommodate an amount of seepage L that does not allow the water level of the seepage L to exceed the connection area 42 . In other words, it is preferable that the lower region 44 can accommodate the seepage water L so that the upper region 46 of the water collection pipe portion 20 can maintain a state in which air can flow. Also, the upper region 46 is open to the atmosphere at the top.

The receiving pit 40 is connected to the water receiving tank 51 via a connecting pipe 70 having a water pump 622 .

The water receiving tank 51 is provided to adjust the amount of the leachate L supplied according to the treatment capacity of the leachate treatment unit 50 . Further, the water receiving tank 51 may have an air diffuser for aerating the leachate L received. By aerating the leachate L in the water receiving tank 51, nitrification occurs in which the ammonium nitrogen in the leachate L is oxidized into nitrate nitrogen. When the leachate L that has been aerated in this manner is supplied to the waste layer through the ventilation pipe section 30, the nitrate nitrogen is reduced to nitrogen gas in the anaerobic region of the waste layer. can be denitrified.

The water receiving tank 51 is connected to the leachate treatment section 50 via a connecting pipe having a water pump 624 and a valve 66 .

The leachate treatment unit 50 includes a conventionally known water treatment device. The leachate treatment unit 50 is configured to release treated water to the outside environment.

The water supply unit 60 has a water supply pipe 64 extending from the water receiving tank 51 to the tip 32 of the ventilation pipe unit 30. The water supply pipe 64 includes a water pump 624 and a valve 68 for pumping up the leachate L. have. Thereby, the water supply unit 60 supplies the leachate L to the ventilation pipe unit 30 .

The water pump 622 is configured to operate continuously when the water level in the receiving pit 40 is equal to or higher than a predetermined water level at which the water pump 622 can supply water. Further, the water pump 624 is configured to operate continuously when the water level of the water receiving tank 51 is equal to or higher than a predetermined water level at which the water pump 624 can supply water. Further, the water receiving tank 51 has a level sensor section for measuring the water level and configured to control opening and closing of the valves 66 and 68 . When the level sensor unit detects that the water level in the water receiving tank 51 is below a predetermined water level, the level sensor unit closes the valve 66 and opens the valve 68 , thereby supplying the leachate L to the ventilation pipe unit 30 . On the other hand, when the level sensor section detects that the water level in the water receiving tank 51 is equal to or higher than the predetermined water level, the level sensor section opens the valve 66 and closes the valve 68 , thereby sending the leachate L to the leachate treatment section 50 .

As the water pump 622 and the water pump 624, conventionally known pumps can be used. Water pump 622 and water pump 624 are preferably capable of transferring 10 to 200 m ³ /hour, preferably 30 to 90 m ³ /hour of water.

The tip of the water supply pipe 64 is preferably arranged at a position 0 cm to 50 cm below the upper edge 14 of the storage unit 10 (or the surface of the waste layer) along the vertical direction. It is more preferable that the tip of the container 10 is positioned 10 to 30 cm below the upper edge 14 of the container 10 (or the surface of the waste layer). The water supply pipe 64 preferably has an end portion whose direction is adjusted so as to supply the leachate L along the direction in which the ventilation pipe portion 30 extends. For example, the water supply pipe 64 may be configured such that the exudate L can pass through the central region in the ventilation pipe portion 30 by arranging the tip portion in the center portion in the radial direction of the ventilation pipe portion 30 . . In addition, the water supply pipe 64 may be configured to be extensible so as to have a length that can reach each ventilation pipe portion 30 , and the water supply pipe 64 is provided for each ventilation pipe portion 30 . may Moreover, it is preferable that the water supply pipe 64 has a valve for controlling opening and closing at the tip thereof. The diameter of the water supply pipe 64 is normally set smaller than the diameter of the ventilation pipe portion 30, preferably 30 to 100 mm. The ratio of the bore diameter of the water supply pipe 64 to the bore diameter of the ventilation pipe portion 30 is preferably set to 0.06 to 0.6.

The concentration measuring unit 80 can measure the concentrations of oxygen, hydrogen sulfide, and methane, and may measure the temperature of the gas. In this embodiment, as shown in FIG. 2, the concentration measuring section 80 is installed at the tip portion 32 of the ventilation pipe section 30 . More specifically, the concentration measurement unit 80 has a detection unit 82 for detecting gaseous components, and the tip of the detection unit 82 reaches the upper edge 14 of the storage unit 10 (or the surface of the waste layer). ) along the vertical direction and above the tip of the water supply pipe 64 .

Next, a waste landfill disposal method according to one embodiment using the waste landfill disposal facility 1 according to the above embodiment will be described.

In the waste landfill disposal method of this embodiment, the concentration of the components contained in the gas discharged from the tip portion 32 of the ventilation pipe portion 30 is measured by the concentration measurement portion 80, and the measurement result is used as an index, and the water supply portion 60 and supplying leachate L from the

Here, with reference to FIG. 3, the relation of various gas concentrations in the waste landfill treatment facility 1 according to the above embodiment will be described. As shown in FIG. 3, the waste landfill facility 1 tends to generate hydrogen sulfide first when the oxygen concentration decreases, and methane when the oxygen concentration further decreases. More specifically, when the oxygen concentration drops to about 15%, hydrogen sulfide tends to be generated, and when the oxygen concentration drops to about 5%, methane tends to be generated. Also, it is presumed that a lot of time is required to improve the place where the oxygen concentration has decreased until methane is generated (that is, the place where the anaerobic state has increased) to a semi-aerobic state. be done.

Based on the gas concentration relationship as described above, in the present embodiment, it is preferable that the gas components used as indicators for determining whether the leachate L should be supplied are methane and oxygen. Further, from the viewpoint of supplying the leachate L before the anaerobic property is greatly increased, when the methane concentration is preferably 50 LEL% or more, more preferably 10 LEL% or more, and/or the oxygen concentration is preferably 10% Thereafter, more preferably, the leachate L is supplied from the water supply unit 60 when the concentration becomes 15% or less.

In the case of this embodiment, taking into account the size of the container 10, the capacity of the leachate L supplied from the water supply unit 60 is usually set to 10 to 200 m ³ /day, preferably 30 to 90 m ³ /day. set. During this time, the leachate L may be supplied continuously, or the leachate L may be intermittently supplied.

As described above, according to the waste landfill treatment facility and the waste landfill treatment method according to the present embodiment, the leachate L is supplied by the water supply unit 60 so as to drop in the ventilation pipe unit 30, Generation of methane can be easily suppressed as compared with the conventional technology. The reason for this is that the leachate L is supplied by the water supply unit 60 so as to drop in the ventilation pipe 30, so that the leachate L reaches deeper into the ventilation pipe 30 while entrained with air. Therefore, it is considered that the air is supplied to a deeper portion of the housing portion 10 . As a result, anaerobicity is greatly increased locally in the storage section 10 due to difficulty in supplying air, and air is supplied even to locations where methane is generated, thereby suppressing the generation of methane. it is conceivable that.

In addition, the waste landfill treatment facility and the waste landfill treatment method according to the present invention are not limited to the above embodiments. Moreover, the waste landfill treatment facility and the waste landfill treatment method according to the present invention are not limited by the above effects. Various modifications can be made to the waste landfill treatment facility and the waste landfill treatment method according to the present invention without departing from the gist of the present invention.

For example, in the waste landfill treatment facility 1 according to the above embodiment, the water supply unit 60 supplies the leachate L, but there is no particular limitation as long as it is water. Alternatively, rainwater, groundwater, or the like may be supplied.

In addition, in the waste landfill treatment facility 1 according to the above-described embodiment, the vent pipe part 30 is branched from the upper part of the water collection pipe part 20 and arranged so as to extend along the vertical direction. The vent pipe portion 30 may branch from the vent pipe portion 30 extending from the water collection pipe portion 20 .

Further, in the above-described embodiment, the water supply unit 60 has the valves 66 and 68, but it may be in the form of the second embodiment shown in FIG. That is, the water supply section 60 has a water supply pipe 64 extending to the tip portion 32 of the ventilation pipe portion 30, and the water supply pipe 64 has a dedicated water pump 6244 for pumping up the leachate L. there is The water receiving tank 51 and the leachate treatment unit 50 are connected via a connection pipe independent of the water supply pipe 64 , and the connection pipe has a dedicated water supply pump 6242 . In such a configuration, the level sensor of the water receiving tank 51 stops the water pump 6242 and starts the water pump 6244 when detecting that the water level of the water receiving tank 51 is below a predetermined water level. On the other hand, when the level sensor unit of the water receiving tank 51 detects that the water level of the water receiving tank 51 is equal to or higher than the predetermined water level, it starts the water pump 6242 and stops the water pump 6244 . The level sensor of the water receiving tank 51 stops both the water pump 6242 and the water pump 6244 when the water level of the water receiving tank 51 is lower than a predetermined water level at which the water pump 6244 can supply water.

Furthermore, a form like the third embodiment shown in FIG. 5 may be used. That is, the water supply pipe 64 may extend from the receiving pit 40 to the tip portion 32 of the vent pipe section 30 . In addition, the water supply pipe 64 has a dedicated water pump 626 for pumping up the leachate L. The receiving pit 40 is connected to the water receiving tank 51 through a connection pipe different from the water supply pipe 64 . Also, the other connection pipe has a dedicated water pump 622 .

Further, in the waste landfill treatment facility 1 according to the above-described embodiment, the water collection pipe portion 20 has a plurality of holes formed in the upper surface portion, but unless the function of the water collection pipe portion 20 is impaired, , a plurality of holes may be formed in the lower surface portion.

In addition, in the method according to the above embodiment, the composition of the gas is measured using the concentration measuring unit 80 installed in the facility 1, but a handy type concentration measuring device can be used more simply. may be measured.

Further, in the method according to the above embodiment, the gas component used as an index for determining whether to supply the leachate L is methane, but the present invention is not limited to this, and hydrogen sulfide may be used as an index for determination. In this case, the leachate L is supplied from the water supply unit 60 when the concentration of hydrogen sulfide reaches preferably 5 ppm or more, more preferably 2 ppm or more.

EXAMPLES Next, the present invention will be described more specifically by showing examples.

In this example, a waste landfill treatment facility as shown in FIGS. 1 and 6 was used. The configurations shown in FIGS. 1 and 6 have been described above. In addition, FIGS. 6A to 6E show the positions of the tip portions of some of the ventilation pipes.

The capacity of the storage part is 470,000 m ³ , the diameter of the main pipe of the water collection pipe is 600 mm, the diameter of the branch pipe is 150 mm, and the diameter of the ventilation pipe is 150 mm.

As the water supply unit, a pump connected to a water supply pipe with a diameter of 65 mm was connected to the water receiving tank through the connection pipe, and leachate was supplied from the water supply pipe to the aeration pipe. The position of the tip of the water supply pipe during the supply of leachate was 20 cm vertically downward from the upper edge of the container.

As a concentration measurement unit, a portable multi-gas monitor (GX-2012 manufactured by Riken Keiki Co., Ltd.) is used to measure oxygen, hydrogen sulfide and methane, and a handy thermometer (HD- 1000 series) was used. As a specific measurement method, the tip of the sensor as the detection portion was placed 10 cm below the upper edge of the housing portion in the vertical direction, and the measurement was performed.

In this example, the concentration and temperature of the components of the gas discharged from the ventilation pipes installed at positions A to E in FIG. 6 were measured over time. 7 to 11 show the measurement results of the concentration and temperature of the components of the gas discharged from the ventilation pipe parts with the tips arranged at positions A, B, C, D, and E. FIG.

[Reference example]
The measurement results in B and C of FIGS. 8 and 9 are shown as reference examples. According to the measurement results, almost no hydrogen sulfide and methane were detected, the oxygen concentration was generally maintained at a value exceeding 20%, and the area around these ventilation pipes in the housing area was semi-aerobic. It was confirmed that the natural environment was maintained. Therefore, it was determined that it was not necessary to supply leachate to these ventilation pipes.

[Comparative Example 1]
On the other hand, according to the measurement results in A of FIG. 7, it was recognized that the methane concentration increased and the oxygen concentration decreased especially in the first half of the period. From these measurement results, it was suggested that anaerobic activity was locally increased around these ventilation pipes in the housing unit. Therefore, following the method of the prior art, a portable blower was used to supply air from the ventilation pipe. Specifically, air was supplied eight times to the ventilation pipe portion related to A (x mark in FIG. 7). However, the long-term lowering effect of methane concentration was low.

[Comparative Example 2]
Further, in the measurement results in D of FIG. 10, it was confirmed that the methane concentration increased from the beginning of the period to the latter half of the period, and the oxygen concentration decreased. From these measurement results, it was suggested that anaerobic activity was locally increased around these ventilation pipes in the housing unit. Therefore, in the same manner as in Comparative Example 1, air was supplied eight times to the ventilation pipe portion related to D (x marks in FIG. 10). However, the long-term lowering effect of methane concentration was low.

From the results of Comparative Examples 1 and 2, when there is a location in the storage unit where the anaerobicity is locally greatly increased such that methane is generated, the air supply by the portable blower controls the location to be semi-aerobic. It was considered difficult to

[Example 1]
Next, after supplying the leachate to the ventilation piping part related to A at about 4.5 m ³ /hour for about 3.5 hours, the supply was stopped for about 2.9 hours. Water was supplied (marked with ♦ in FIG. 7). As a result, the methane concentration decreased to around 0 LEL %, the hydrogen sulfide concentration also decreased, and the oxygen concentration increased to around 20%. Moreover, such a state was maintained for a certain period of time.

[Example 2]
In addition, after supplying the leachate to the ventilation pipe section related to D at a rate of about 4.5 m ³ /hour for about 3.5 hours, the supply was repeatedly stopped for about 2.9 hours. was supplied (marked ♦ in FIG. 10). As a result, the methane concentration decreased to around 0 LEL %, the hydrogen sulfide concentration also decreased, and the oxygen concentration increased to around 20%.

[Example 3]
In addition, after supplying the leachate to the ventilation pipe part related to E at about 4.5 m ³ /hour for about 3.5 hours, the supply was repeatedly performed for about 2.9 hours, and the leachate was supplied from the water supply part. was supplied (marked ♦ in FIG. 11). As a result, the methane concentration decreased to around 0 LEL %, the hydrogen sulfide concentration also decreased, and the oxygen concentration increased to around 20%. Moreover, such a state was maintained for a certain period of time.

From the results of Examples 1 to 3, the supply of leachate to the ventilation pipe improves the surroundings of the ventilation pipe in the storage part to a semi-aerobic environment, and such a state can be maintained. I understand.

1: Waste landfill treatment equipment,
10: housing portion, 12: bottom portion, 14: upper edge,
20: water collection piping part, 202: main pipe, 204: branch pipe, 22: downstream end, 28: upstream end,
24: lower region, 26: upper region,
30: ventilation pipe part, 32: tip part,
40: Receiving pit, 42: Connection area, 44: Lower area, 46: Upper area,
50: leachate treatment unit, 51: receiving tank,
60: water supply unit, 622, 624, 626: pump,
64: water supply piping, 66, 68: valves,
70: connection pipe,
80: density measurement unit, 82: detection unit,
W: waste, L: leachate

Claims (3)

Using a waste landfill facility that treats waste semi-aerobically,
The waste landfill treatment equipment includes:
a storage unit that stores the waste;
A water collection piping section arranged along the bottom of the storage section and capable of collecting and discharging leachate seeping from the waste, wherein at least one end of the collection piping section is open to the atmosphere. a water pipe;
A ventilation pipe branched from the water collection pipe and having a plurality of ventilation holes formed in a side wall thereof, the ventilation pipe extending vertically in the waste and having a distal end protruding upward from the waste. a plurality of ventilation pipes arranged in such a manner as to
a water supply unit that supplies water so as to drop a radial central region in the ventilation pipe unit,
A waste landfill disposal method, comprising measuring concentrations of components contained in gas discharged from the tip portion of the ventilation pipe portion, and supplying water from the water supply portion using the measurement result as an index. 2. The waste landfill disposal method according to claim 1 , wherein the index concentration is methane concentration or oxygen concentration. The waste landfill disposal method according to claim 1 or 2 , wherein the water supplied by said water supply unit is said leachate.

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