JP2006281006A - Method of treating incineration ash, method of sprinkling water to incineration ash layer, and sprinkler for incineration ash - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To wash incineration ash in pretreatment with a small water amount in an early stage. <P>SOLUTION: At the time of reclaiming the incineration ash in a final disposal site, the pretreatment using water sprinkling treatment and ventilation treatment together is executed to the incineration ash before reclamation. By using the ventilation treatment together, the pretreatment of lowering the TOC of leachate to about 100 mg/l in about 40 days is performed. Compared to the case of just washing the incineration ash with washing water before the reclamation, the pretreatment is performed with a smaller water amount. After the pretreatment, even when a water sprinkling amount is suppressed to the amount of 2 mm/day for instance, the quality of the leachate about the same as the one when it is 4 mm/day is maintained. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for treating incineration ash at a final disposal site, and in particular, by pre-treating incineration ash before landfilling, the stabilization by reducing the concentration of heavy metals eluted from leachate after landfilling is performed at an early stage. It is an effective technology to apply to.

  At the final disposal site, organic substances, heavy metals, etc. contained in landfill incineration ash are washed out and insolubilized by exposing the landfill incineration ash to rain or artificially sprinkling, making it difficult to elute It is stabilized to a high state. In such a stabilization process, as described above, since the landfill incineration ash is subjected to rain or artificial watering, the landfill incineration ash discharges liquids containing organic matter, salts, heavy metals, etc. called leachate that permeated through it. Is done.

  In such stabilization treatment, instead of relying on natural rainfall for the purpose of processing efficiency, the final disposal site is covered with a cover, such as a building, for artificial control, and artificially stabilized by sprinkling water under control. There are increasing examples of advancing.

  In the method of artificial stabilization, there are an example of watering the incinerated ash after landfilling and an example of cleaning the incinerated ash before landfilling. In both cases, leachate is generated in the process of stabilization, and leachate treatment facilities are installed according to the amount generated to reduce pollutants to the level shown in the environmental standards.

For example, Patent Document 1 proposes a technique for increasing the purification rate of landfill incineration ash at the final disposal site by pre-processing before the landfill of incineration ash, thereby speeding up reuse of the final disposal site. Yes.
JP 2002-59106 A

  As described above, various proposals have been made for stabilization of leachate generated during the treatment of incinerated ash at the final disposal site. However, the present inventor notices that there are problems to be further improved. It was.

  In the treatment method of spraying the incinerated ash after the landfill, leachate having a high concentration of organic substances, heavy metals, etc. is discharged from the incinerated ash immediately after the landfill. In normal landfill, incineration ash is sequentially piled up according to the incineration ash being carried in, and water spraying to the landfill incineration ash is repeated each time it is piled up. Therefore, high concentration leachate is always discharged from the final disposal site during the service period.

  Moreover, the incineration ash carried in near the end of the landfill is piled up on the uppermost layer of the incineration ash layer. Therefore, the discharge of leachate generated by sprinkling water on the uppermost layer must pass through the landfill incineration ash layer accumulated in layers to the lowermost layer, which takes a long time. Concentrated leachate will be generated. Even after landfill is completed, it is necessary to operate the leachate treatment facility for a long period of time and continue to treat leachate.

  In this way, in the treatment method of spraying the incinerated ash after landfill, since high concentration leachate is generated for a long time from the start of operation of the final disposal site to the end of landfill, the final disposal site is substantially closed. However, the operation of the leachate treatment apparatus will be continued for a long time, and the operation cost will be high. Moreover, since high concentration leachate continues to be discharged over a long period of time, a state with a high risk to the surrounding environment will continue for a long period of time.

  In order to solve such a problem, as described above, a treatment method in which incineration ash is pretreated and washed before landfilling of incineration ash at a final disposal site has been proposed. In the treatment method that cleans the incineration ash before the landfill, it can be landed after changing the incineration ash to a safe state, so the leachate from the landfill incineration ash at the final disposal site is considered to be highly safe, The service period can be shortened accordingly.

  However, in order to perform cleaning so that the elution amount of organic substances and heavy metals from the incineration ash can be suppressed to a predetermined concentration in a short period from the generation of the incineration ash to the landfill to the final disposal site, a large amount of Requires wash water. For this reason, a water treatment facility for treating a large amount of water after washing is required separately, and there is a concern about an increase in treatment costs associated with the pretreatment.

  An object of the present invention is to quickly clean the incineration ash in the pretreatment with a small amount of water.

  The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

  Of the inventions disclosed in the present application, the outline of typical ones will be briefly described as follows.

  The present invention relates to a method for treating incineration ash, wherein the incineration ash is a landfill incineration ash subjected to water spray treatment in a building, wherein the incineration ash is sprinkled to a predetermined density before landfill, It is characterized in that pre-processing is performed in the processing. In such a configuration, the aeration treatment is characterized in that aeration is performed in a direction opposite to a penetration direction of the water by the watering treatment into the incinerated ash. In this configuration, the watering treatment and the aeration treatment are performed in parallel. The watering treatment is characterized in that the watering amount per day is set to 3 mm or more and 6 mm or less. In any one of the configurations described above, the ventilation process is characterized in that the ventilation speed is set to 1 mm / second or more and 10 mm / second or less.

  The present invention is a method for treating incineration ash that performs water spraying treatment on landfill incineration ash that has been landfilled with incineration ash, wherein the incineration ash is sprinkled to a predetermined density before landfilling, The elution amount is stabilized with time so as to reduce the change over time in the elution amount of the eluate from the incinerated ash by the water sprayed by the watering treatment. Such a water permeation speed improvement process is a process in which aeration is performed in a direction opposite to the direction of penetration of water into the incinerated ash by the watering process.

  The present invention is a method for treating incineration ash that performs water spraying treatment on landfill incineration ash that has been landfilled with incineration ash, wherein the incineration ash is sprinkled to a predetermined density before landfilling, The water permeation location non-uniformity suppression process for suppressing the non-uniformity of the water permeation location in the incinerated ash of the water sprayed by the water sprinkling treatment is performed. Such a water permeation location non-uniformity suppressing process is a process in which aeration is performed in a direction opposite to a permeation direction of water into the incinerated ash by the watering process.

  The present invention is a method for treating incineration ash that performs watering treatment on the landfill incineration ash in which the incineration ash is landfilled, wherein the incineration ash is pretreated before landfilling, and the pretreatment is performed as follows: It is one of a process for stabilizing the elution amount with time and a process for nonuniformity of water permeation in the above configuration.

  The present invention is a watering method for sprinkling water into an incinerated ash layer, wherein water is sprayed into the incinerated ash layer, and the water sprayed together is aerated against the water permeation direction of the incinerated ash layer. And If such a watering method is adopted as pretreatment of incineration ash before landfilling, it is preferable that stabilization of incineration ash can be carried out with a small amount of water at an early stage before landfilling.

  The present invention is a watering device for sprinkling water on an incinerated ash layer, provided on a water permeable layer formed on the bottom side, and incinerated ash storage means for sprinkling incinerated ash at a predetermined density and storing it. An incineration ash water spraying device comprising: a ventilation means for venting the inside of the incineration ash storage means; and a sprinkling means for watering the incineration ash layer stored in the incineration ash storage means. By constructing the incineration ash sprinkler in this way, the sprinkling treatment performed to stabilize the leachate of the incineration ash can be performed efficiently.

  Among the inventions disclosed in the present application, effects obtained by typical ones will be briefly described as follows.

  In the present invention, since the incineration ash is pretreated by watering and aeration before landfilling the incineration ash, it is possible to keep the amount of organic substances, heavy metals, etc. in the leachate generated from the landfill incineration ash after landfill low. it can.

  In the pretreatment, by adopting aeration treatment in conjunction with watering treatment, compared to the case where such aeration treatment is not used together, the amount of water used in the pretreatment is suppressed, while organic substances, heavy metals, etc. from leachate related to the pretreatment are used. It is possible to shorten the stabilization period to keep the amount of elution low.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiment, and the repetitive description thereof may be omitted.

  The present invention relates to a method for treating incineration ash at the final disposal site. By pre-treating the incineration ash before landfilling, early reduction of the concentration of eluted heavy metals, etc. in leachate generated from the incineration ash after landfilling is achieved. This is an effective technology. That is. Before incineration ash is landfilled at the final disposal site, pre-treatment is performed on the managed site.

  Such pretreatment has been proposed in the past by incinerating incinerated ash before landfilling into a layer with a predetermined density and a predetermined layer thickness, and applying artificial watering and ventilation to the incinerated ash layer. Compared with cleaning as a pretreatment, the amount of water used and the treatment period can be significantly shortened. The incinerated ash that has been subjected to the predetermined pretreatment in this way is dropped into a buried facility at a predetermined final disposal site and buried. The buried incineration ash will be periodically sprinkled with artificial water as before to manage the leachate.

  Such a procedure is shown in FIG. That is, in step S100, the incineration ash is brewed with a predetermined density and a predetermined layer thickness. As the target incineration ash, bottom ash, fly ash (fly ash), etc. discarded from the incineration facility may be assumed. For example, the disposal may be performed by setting a processing area in a part of the final disposal site where the landfill processing of incinerated ash is performed.

The rolling-out may be performed using a backhoe or the like, and the rolling-out thickness may be set to 30 cm, for example. For example, the density may be set to 1.2 g / cm ³ or more and 1.4 g / cm ³ or less. Is less than 1.2 g / cm ^3, there are disadvantages such as the management out spreaders, because there are disadvantages such that it is difficult to maintain the water permeability exceeds ^{1.4g / cm 3, 1.2g / cm} 3 or more, A range of 1.4 g / cm ³ or less was judged good. More preferably, it is the range of 1.2 g / cm ³ or more and 1.3 g / cm ³ or less.

As an inconvenience of the start-up management, for example, there is a problem of density management. It is generally assumed that heavy machinery is used for the spreading work. However, when such heavy machinery is used, it is unavoidable that humans will incinerate the incinerated ash and spread it with rakes. There is a problem that it becomes stronger and density management at less than 1.2 g / cm ³ is substantially difficult to perform.

  In step S200, the incinerated ash sprinkled to a predetermined density and a predetermined layer thickness is subjected to a predetermined amount of artificial watering and an aeration process at a predetermined flow rate. For example, as artificial watering, water with a watering amount equivalent to 1.3 mm is sprinkled over the incinerated ash layer sprinkled out for 5 to 10 minutes. Such watering is performed three times a day. The amount of water per day is equivalent to 4 mm. The suitable range of the amount of water spray is 3 mm / day or more and 6 mm / day or less. If the amount is less than 3 mm / day, the amount of transpiration is greatly affected by the amount of water sprayed, and the amount of water that becomes leachable water decreases, resulting in a disadvantage that the cleaning efficiency decreases. If the amount exceeds 6 mm / day, the amount of cleaning water becomes excessive. is there.

  In sprinkling water, for example, aeration treatment is performed from below the incinerated ash layer to be sprinkled into the incinerated ash layer. Aeration treatment may be performed at an aeration rate of 1 mm / second or more and 10 mm / second or less for the amount of water spray in the above range. If it is less than 1 mm / second, the effect of the aeration treatment cannot be sufficiently obtained, and there is a disadvantage that stabilization is delayed, and if it exceeds 10 mm / second, the amount of ventilation becomes excessive, and inconveniences such as incineration ash drying due to ventilation occur. It is. More preferably, it is 1 mm / second or more and 3 mm / second or less. According to the inventor's study, for example, a combination of aeration speeds of 2 mm / second was preferable for a water spray amount of 4 mm / day. In this way, ventilation is performed against the direction of water permeation passing through the incinerated ash layer downward.

  In the above watering treatment, it was found that when such aeration treatment was performed, the change over time after the start of watering of the water permeation speed passing through the incinerated ash layer of the sprinkled water was reduced as compared to the case where such aeration treatment was not performed. .

  The elution amount of eluate such as heavy metals and organic matter in the incinerated ash layer into the infiltrated water is greatly influenced by the water transmission rate. However, in the pretreatment according to the present invention, the change with time of the water permeation rate is small as described above, so that the change with time of the elution amount of the eluate in the leachate is small, and a stable elution state is ensured. That is, the slow change due to the passage of time of the water permeation rate is suppressed, and the fluctuation of the elution amount with time is stabilized, and as a result, it is possible to secure a highly reliable pretreatment quality.

  In addition, if water is sprayed without using aeration, a water-permeable road is inevitably formed in the incinerated ash layer, and water tends to flow along the road. On the other hand, when the aeration treatment is performed from the lower side against the water permeation direction, the inside of the incinerated ash layer is permeated on average, and the non-uniformity of the water permeation location on the water permeation surface is suppressed.

  Such aeration treatment may be performed in parallel with watering. Alternatively, the watering process and the aeration process may be performed in succession. In such a case, the sprinkling process may be performed first or the aeration process may be performed first, but it is necessary not to perform both processes with an excessive time interval. Preferably, the subsequent processing may be continued after the end of the previous processing. The state of the processing in step S200 is schematically shown in FIG.

  Moreover, in FIG. 3, the whole structure of the sprinkling apparatus for incineration ash which can perform the sprinkling process which used together the ventilation process of incineration ash of this step S200 efficiently was shown in the cross section. That is, as shown in FIG. 3, the water spraying apparatus 10 for incineration ash according to the present invention forms the side wall 12 by stacking blocks 12a and the like on the periphery of the non-permeable base 11 as storage means for the incineration ash. Thus, the incinerated ash can be charged and stored in the interior surrounded by the side wall 12. Although not shown in the drawings, the side wall 12 may be provided with a door that can be opened and closed, and by opening and closing the door, the incineration ash can be appropriately introduced and removed.

  Further, although not shown, the incineration ash water spraying device 10 is entirely covered with a building or the like so that natural rain does not fall on the incineration ash stored in the incineration ash storage means configured as described above. That's fine. Or you may install in the building of a final disposal site.

  As shown in FIG. 3, the interior surrounded by the side wall 12 is provided with a drainage layer 13 on the base 11. The drainage layer 13 is formed of a crushed stone layer 13a in which crushed stone having a particle diameter of, for example, about 10 to 20 mm is provided with a predetermined layer thickness. A perforated pipe made of vinyl chloride or the like is embedded in the crushed stone layer 13a as a water collecting pipe. The water collection pipe is connected to a leachate treatment apparatus (not shown) so that the leachate collected by the water collection pipe is treated and managed.

  On the crushed stone layer 13a, a ventilation layer 14 is provided by geotextile, crushed stone, or the like. A perforated pipe 15a made of vinyl chloride or the like having a plurality of small holes around it is buried in the ventilation layer 14 as an air supply pipe 15 as ventilation means. Although not shown, the perforated tube 15a is connected to a pump for supplying air, and for example, air is perforated to the incinerated ash layer so that air can be vented at a predetermined flow rate such as 2 mm / second with respect to the area. It is configured so that it can be fed inside.

  On the ventilation layer 14 passing through the perforated tube 15a, a ventilation layer 16 is further provided with a thin layer thickness as shown in FIG. The ventilation layer 16 is also composed of geotextile, crushed stone, and the like. The ventilation layer 14 and the ventilation layer 16 have different particle sizes. On the ventilation layer 16, a net 17 such as a trical net 17 a that serves to prevent the incineration ash from dropping into the ventilation layer is provided.

  In this way, the incinerated ash storage means for storing the incinerated ash is configured by surrounding the tricarnet 17a with the side wall 12. Above the incinerated ash storage means having such a configuration, the water spraying means 18 is configured by providing a water spray nozzle 18b in a water supply pipe 18a connected to a water supply pump (not shown).

  If the sprinkling device 10 for incinerated ash having such a configuration is used, pretreatment before incineration of the incinerated ash using both watering treatment and aeration treatment can be performed efficiently. For example, the incineration ash brought from the incineration facility is thrown into the incineration ash storage means of the incineration ash sprinkler 10 provided at one corner of the final disposal site. After the charging, it is rolled out into a layer with a predetermined density and a predetermined layer thickness. After spraying, water is periodically sprayed from the water spray nozzle 18b onto the incinerated ash layer with the predetermined water spray amount as described above.

  At the same time, the perforated tube 15a is used for aeration with a predetermined air supply amount as described above. As shown in FIG. 3, the ventilation is performed from the lower side to the upper side in the incinerated ash layer so as to oppose the water permeation direction of the sprinkled water. Sprinkled water, which is treated to stabilize the amount of elution by aeration treatment in this way, permeates through the incineration ash layer with increased uniformity, efficiently cleans the incineration ash, and leaches into the drainage layer 13. It reaches the water and is sent to the leachate treatment apparatus by the water collecting pipe in the drainage layer 13 and subjected to a predetermined treatment. Thereafter, for example, it is discharged outside the field or reused.

  Completion of the pretreatment in step S200 may be determined using, for example, the total organic carbon concentration (TOC) in the leachate as an index. For example, it may be determined that the pretreatment is completed when the TOC of the leachate reaches 100 mg / l. In order to reach such a criterion, it was confirmed by experiments that pretreatment was completed in about 40 to 50 days, although there were some differences due to the effects of the properties of incinerated ash.

  Of course, other EC (electrical conductivity) or the like may be used as an index for determination. The advantage of using TOC as a judgment index is that it is a numerical value that directly indicates the index substance as compared with the case where TOC is not used as an index. Incidentally, when other EC or the like is used as a determination index, more specifically, a numerical value of 1.0 S / m may be adopted as a reference.

The pretreated incinerated ash that has been pretreated in step S200 in this manner is landed in a predetermined manner, for example, by dropping it in the storage structure of the final disposal site in step S300. The landfill procedure may be performed as usual. For example, a backhoe or the like may be rolled out and rolled at a density of 1.7 to 1.8 g / cm ³ . The state of step S300 is schematically shown in FIG.

In step S400, as shown in FIG. 2 (b), the pretreated incineration ash is put into the storage structure of the final disposal site, and then sprayed to a predetermined layer thickness. Manage leachate. For example, it is rolled out at a predetermined layer thickness so as to have a density of 1.7 to 1.8 g / cm ³ , subjected to rolling, and then 0.7 mm × 3 times / day, that is, about 2 mm / day of dispersion. Sprinkle with water. The amount of leachate is about 1.6 to 1.9 mm / day, and the TOC of leachate is already 100 mg / l or less because it has already been treated in the pretreatment.

  As shown in FIG. 2 (c), after the landfill of the final disposal site is completed with the TOC maintained at 100 mg / l or less, the building may be removed or the site may be used. In FIG. 2 (c), it is further assumed that the leachate is stabilized after the landfill is completed, and when the landfill is completed, an underground irrigation pipe 21 such as a drip tube 21a is buried in the landfill 20 and the ground It shows a case where water is dropped from the middle irrigation pipe 21 into the buried portion and the stabilization process is continued by the leachate treatment apparatus. In such stabilization treatment, since the TOC of leachate has already been suppressed to 100 mg / l or less, the operating state may be maintained at the minimum level of the leachate treatment process.

  Compared to the case where the pretreatment of the incineration ash is not performed as described above, the treatment load for stabilizing leachate after completion of landfill can be kept small. Furthermore, the period of the stabilization process can be shortened.

  Further, in the pretreatment described above, the amount of sprinkling water used is much smaller than the amount of washing water used as the pretreatment so far. It is efficient and preferable if the leachate generated in the pretreatment is treated with the leachate treatment equipment at the final disposal site, but when using a large amount of washing water more than that used for artificial watering to landfill incineration ash, It is necessary to set the capability of the leachate treatment apparatus in accordance with the pretreatment, which increases the equipment cost.

  In addition, since leachate treatment equipment normally performs leachate stabilization processing continuously after completion of landfill, the increased capacity increased for pretreatment is wasted after completion of pretreatment. Become. On the other hand, a leachate treatment apparatus may be installed exclusively for pretreatment, but in such a case, the pretreatment cost is further increased, and it may be sufficiently assumed that it is difficult to adopt as an effective measure.

  However, in the present invention, it is possible to reduce the amount of sprinkling used in the pretreatment, so that the amount of leachate generated in the pretreatment can be reduced to a level almost comparable to the amount of leachate generated from landfill incineration ash. Unlike the case where washing water is used, the leachate treatment device used in the leachate management of landfill incineration ash at the final disposal site can be used without specially increasing the capacity of the leachate treatment device. .

  The effectiveness of the pretreatment employed in the present invention described above is confirmed by the following experiment. First, as shown in FIG. 4, a pretreatment experimental apparatus 30 capable of performing the above pretreatment on a bench scale was created. As shown in FIG. 4, the pretreatment experimental apparatus 30 is configured by filling a column 31 with a drainage layer 32 and an incineration ash layer 33 in a predetermined layer thickness from below. Below the column 31, a drain port 34 leading to the drainage layer 32 is provided, and a water supply device 36 for supplying water into the column is provided on the lid 35 above the column 31.

The column 31 is filled with a crushed stone having a particle diameter of about 10 to 20 mm as a drainage layer 32 with a thickness of 5 cm. On the drainage layer 32, an incineration ash layer 33 is filled with a layer thickness of 30 cm, which is comparable to the squeezed thickness. The packing density of the incinerated ash layer 33 was adjusted to 1.3 g / cm ³ . Water supply from the water supply device 36 was set to 1.3 mm / 3 times / day so as to correspond to the amount of water sprayed to the incineration ash. This amount of water spray corresponds to 3.9 mm / day. In addition, aeration was performed at a rate of 2 mm / second from below the drain port 34 into the column 31. In addition, the temperature at the time of experiment was 25 degreeC.

  Under such conditions, leachate generated by supplying water from the drain outlet 34 to the incineration ash layer 33 was collected, and the TC of the leachate was observed over time. FIG. 5 shows the results of examining the TOC of leachate obtained by filling the column 31 in the above manner and supplying water for the incinerated ash A and B collected at different times from the same incineration facility. . In FIG. 5, the vertical axis indicates the TOC concentration in mg / l, and the horizontal axis indicates the elapsed days.

  As shown in FIG. 5, the incineration ash A and B have different collection times and different components, but the TOC changes with time showed almost the same tendency. As shown in FIG. 5, the change in TOC with time increases initially, shows a peak in several days, and then decreases. In the experiment shown in FIG. 5, it was confirmed that the TOC decreased to 100 mg / l or less in the period from 35 days to 40 days after the start of the experiment.

  For incineration ash discharged from the same incinerator, even if there is a change in the composition of the incineration ash, such as when the incineration ash is collected at different times, in the pretreatment experiment, the TOC of the leachate ages over time regardless of such change. The change shows almost the same tendency, and it is confirmed that the TOC reaches 100 mg / l or less in about 40 days. The above experiment is an experiment at a temperature of 25 ° C., and assuming that the temperature in winter is low, the TOC will be reduced to 100 mg / l or less between the 40th and the 50th with some delay. The present inventor has determined that it does not matter.

Next, in order to examine the optimum water spray amount when the pretreated incineration ash is landfilled, the relationship between the water spray amount and the change in TOC over time was examined by experiments. In the experiment, the exposed layer thickness was 30 cm, and the density of the incinerated ash layer 33 was 1.8 mg / cm ³ . As shown in FIG. 6, the watering amount was set such that the watering amount per day was 4 mm / day and 2 mm / day. As a result, it was confirmed that the change in TOC with time was almost the same at 4 mm / day and 2 mm / day.

  The sprinkling amount of 4 mm / day is equivalent to the standard sprinkling amount in the conventional landfill method, but even with half that amount, that is, 2 mm / day, the change in TOC over time is almost the same as in the case of 4 mm / day. I found out. That is, when the incinerated ash subjected to the pretreatment according to the present invention is landfilled, it is confirmed that the leachate can be stabilized in substantially the same period with half the average water spray amount when the treatment is not performed.

Therefore, the present inventor performs the pretreatment of the incineration ash so that the TOC becomes 100 mg / l or less between the 40th and the 50th in the pretreatment, and the watering amount after the landfill of the pretreated incineration ash Can be set as 2 mm / day amount from the experiment.

Next, it is sprinkled at a density of 1.8 g / cm ³ , which is the average landfill density of incinerated ash at a conventional final disposal site, and the amount of water sprayed is 2 mm / day, resulting in a TOC of 100 mg / l or less. The periodical measure until 40 days to 50 days was taken, and after 40 days, the change in the TOC of the leachate when it was increased was examined. Results when pre-treated incineration ash and untreated incineration ash are filled at a thickness of 20 cm and a density of 1.8 g / cm ³ , watering is performed, the same incineration ash is added 40 days later, and watering is continued. Is shown in FIG.

  Compared with untreated, the TOC concentration of the leachate of pretreated incinerated ash is kept low. In the case of untreated incineration ash, the TOC concentration rose again due to the influence of the incineration ash that was accumulated later. As a result, when landfill is performed without pretreatment, it is expected that such leachate with high concentration or high concentration will be discharged, but when incinerated ash that has been pretreated is landfilled. It was confirmed that the TOC concentration of leachate after landfill can be kept sufficiently low.

  From the above results, if the present invention is applied, the quality of leachate after landfill of pretreated incinerated ash is stabilized by pretreatment. The organic and inorganic concentrations of leachate discharged from the incinerated ash layer after landfill are kept low. The quality of the leachate discharged from the pretreatment process is stable, and the design and operation of the leachate treatment facility becomes easy. Furthermore, as an advantage and feature regarding landfill management, incineration ash can be brought into a safe state in a short period of time by pretreatment. This state is not easily affected by physical effects such as rolling pressure in the landfill process. Water quality is maintained even if the incineration ash increases during the landfill process. Even if the depth of the landfill site is increased, the quality of leachate will be kept low. Therefore, it is possible to secure the landfill capacity by increasing the landfill depth in locations where the site area of the final landfill site is difficult.

  As mentioned above, the invention made by the present inventor has been specifically described based on the embodiment. However, the present invention is not limited to the embodiment, and various modifications can be made without departing from the scope of the invention. Needless to say.

  In the description of the embodiment, the explanation of application of the present invention is an example of application in a closed disposal site where landfill of incineration ash is performed in a building, and predetermined landfill is sprayed and managed. However, it goes without saying that other disposal methods may be applied.

  The present invention can be used in a landfill method for incineration ash at a final disposal site.

It is a flowchart which shows the process sequence of incineration ash. (A) is the explanatory view which showed typically the condition of pre-processing, (b) the condition of a landfill process, (c) is the condition after completion of a landfill, respectively. It is explanatory drawing which shows an example of the water spray apparatus for incineration ash. It is explanatory drawing which shows the structure of a pre-processing experimental apparatus. It is explanatory drawing which shows the result of having investigated the influence of the property change of the target incineration ash in a pretreatment. It is explanatory drawing which shows the result of having investigated the influence of the sprinkling amount in the landfill of pre-processed incineration ash. It is explanatory drawing which shows the effect of the pre-processing of the incineration ash in stacking.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Sprinkling device for incineration ash 11 Base 12 Side wall 12a Block 13 Drainage layer 13a Crushed stone layer 14 Ventilation layer 15 Air supply pipe 15a Perforated pipe 16 Ventilation layer 17 Net 17a Water spray means 18a Water supply pipe 18b Water spray nozzle 20 Landfill part 21 Underground irrigation pipe 21a Drip tube 30 Pretreatment experimental device 31 Column 32 Drainage layer 33 Incinerated ash layer 34 Drainage port 35 Lid 36 Water supply device

Claims (12)

A method for treating incineration ash by spraying landfill incineration ash that has been incinerated ash,
The incinerated ash treatment method is characterized in that the incinerated ash is sprinkled to a predetermined density before landfilling and pretreated by watering treatment and aeration treatment. The method for treating incinerated ash according to claim 1,
The incineration ash treatment method is characterized in that the aeration treatment is conducted in a direction opposite to a penetration direction of water into the incineration ash by the watering treatment. In the method for treating incinerated ash according to claim 2,
The method for treating incinerated ash, wherein the watering treatment and the aeration treatment are performed in parallel. In the processing method of the incineration ash of any one of Claims 1-3,
The method for treating incinerated ash is characterized in that the watering amount per day is set to 3 mm or more and 6 mm or less. In the processing method of the incineration ash of any one of Claims 1-4,
The method for treating incineration ash is characterized in that the aeration rate is set to a ventilation speed of 1 mm / second or more and 10 mm / second or less. A method for treating incineration ash by spraying landfill incineration ash that has been incinerated ash,
The incineration ash is sprinkled to a predetermined density before landfilling, watering treatment, and elution amount aging stabilization processing that reduces the time-dependent change in the amount of elution from the incineration ash by the water sprayed water A method for treating incinerated ash, wherein The method for treating incinerated ash according to claim 6,
The treatment method for incineration ash characterized in that the elution amount stabilization treatment with time is a treatment for aeration in a direction opposite to the infiltration direction of water into the incineration ash by the watering treatment. A method for treating incineration ash by spraying landfill incineration ash that has been incinerated ash,
The incineration ash is sprinkled to a predetermined density before landfilling, water spraying treatment, and water permeation site non-uniformity suppression treatment for suppressing non-uniformity of water permeation sites in the incineration ash of water sprayed by the water sprinkling treatment. A method for treating incinerated ash, wherein The method for treating incinerated ash according to claim 8,
The treatment method for incineration ash is characterized in that the water permeation location non-uniformity suppression treatment is a treatment for venting in a direction opposite to a penetration direction of water into the incineration ash by the watering treatment. A method for treating incineration ash by spraying landfill incineration ash that has been incinerated ash,
The incineration ash is pre-treated before landfill,
The incineration ash treatment method according to any one of claims 6 to 9, wherein the pretreatment is applied to the incineration ash treatment method according to any one of claims 6 to 9. A watering method for watering the incinerated ash layer,
A method of sprinkling water into the incinerated ash layer, wherein water is sprinkled on the incinerated ash layer, and the water sprayed together is aerated against the direction of water permeability of the incinerated ash layer. A watering device for watering the incinerated ash layer,
Incinerated ash storage means that is provided on the water-permeable layer formed on the bottom surface side and spills and stores the incinerated ash at a predetermined density so that it can be removed;
A ventilation means for venting the inside of the incinerated ash storage means;
A spraying device for incineration ash comprising spraying means for spraying water into the incineration ash layer stored in the incineration ash storage unit.

Images