JP2016032786A - Incineration residue treatment method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an incineration residue treatment method in which waste water containing an easily soluble component produced in a washing process is prevented from being discharged to the outside of treatment equipment as it is.SOLUTION: There is provided the incineration residue treatment method for treating incineration ash generated by incineration of waste, the method includes: a cooling step in which the incineration ash is put into a cooling tank 12A filled with cooling water to cool the incineration ash; a washing step in which the incineration ash taken out from the cooling tank 12A is continuously ventilated and water is intermittently sprinkled to the incineration ash to remove easily soluble component from the incineration ash. Waste water produced by washing the incineration ash in the washing step is used as cooling water to be put into the cooling tank 12A.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for treating incineration residues, including a cleaning step for cleaning incineration residues generated when incineration processing waste, for example, incineration ash.

  Incineration residue generated when incinerating waste, for example, incineration ash, contains easily eluted components, that is, heavy metals such as Pb and organic matter, so when final disposal or recycling of incineration ash These easily eluting components are often problematic. In the stabilization of incineration ash, it has been found that long-term elution behavior after landfilling can be improved by carrying out a washing process before landfilling to a disposal site and removing easily eluted components. Moreover, in the current situation where the capacity of the disposal site is tight due to the difficulty of construction of the final disposal site, the ability to recycle incineration ash that accounts for a large amount of landfill will greatly contribute to the extension of the life of the existing disposal site. A major obstacle in the recycling of incineration ash is the elution of easily eluted components from the incineration ash. With regard to this problem, it has been found that the properties of the incineration ash can be improved significantly by cleaning the incineration ash, and the cleaning processing is a promising technique in the future incineration ash processing.

  Patent Documents 1 and 2 describe a process of installing a cleaning facility in an incinerator and promoting stabilization of incineration ash. The incineration ash treatment method described in Patent Document 1 includes a cleaning process, a drying process, a sorting process, and a granulating process.

  In the washing process, after removing metal pieces and clinker-like ingots from the incineration ash, the incineration ash is subjected to salt elution by blowing CO2 gas or injecting acid into at least one stage of washing water. At the same time, it is washed with water in a 2-3 stage washing tank equipped with a chemical injection device to suppress elution of heavy metals, and unburned organic substances, carbon fine particles and fine powder are washed and removed, and at the same time, incineration ash The salt content is eluted and removed, and the eluted heavy metals are also washed away.

  In the drying process, the incinerated ash is dehydrated by a dehydrator and dried using steam or fuel oil as a heat source. In the sorting step, iron is removed from the dried incineration ash, and nonferrous metals are further removed. In the granulation step, the remaining nonmetallic substance is classified according to particle size, then pulverized and polished, and processed into particles.

  The stabilization method of incineration ash and the waste incineration facility described in Patent Document 2 include a cooling cleaning process and an incinerator cooling process. In the cooling and washing process, washing water is sprayed on the incineration ash generated by burning the waste in the incinerator to cool the incineration ash and to elute easily eluted components contained in the incineration ash. In the incinerator cooling process, the contaminated water discharged in the cooling and washing process is sprayed inside the incinerator to cool the incinerator.

Japanese Patent No. 2670417 Japanese Patent No. 4368733

  However, in the method for treating incineration ash described in Patent Documents 1 and 2, in the step of washing incineration ash, a large amount of waste water containing easily eluted components is generated, and facilities and costs for treating or disposing the waste water There was a big problem.

  An object of the present invention is to prevent wastewater containing easily eluted components generated in a cleaning process from being discharged out of the processing facility as it is in a processing facility for processing incineration residues.

  The present invention is an incineration residue treatment method for treating incineration residue generated by combustion of waste, and cooling the incineration residue by placing the incineration residue in a cooling tank containing cooling water; A step of continuously ventilating the incineration residue taken out from the cooling tank, and intermittently watering the incineration residue to remove easily eluted components from the incineration residue, and the washing Waste water generated by washing the incineration residue in the process is used as cooling water to be put into the cooling tank.

  The present invention is provided with a waste water treatment step for separating the waste water into the easily eluted component and water before putting the waste water into the cooling bath, and the water separated in the waste water treatment step is supplied to the cooling bath. Use as cooling water to fill.

  In the present invention, the cleaning step includes the amount of the incineration residue to be cleaned and the amount of the incineration residue to be cleaned so that a liquid-solid ratio between the waste water generated by cleaning the incineration residue and the incineration residue after cleaning is 1 or less. Set the amount of watering.

  The present invention transfers the incineration residue that has absorbed the cooling water in the cooling tank to a landfill site.

  The present invention divides the incineration residue put into the cooling tank into a water absorption residue that absorbs the cooling water and a cleaning residue that is transferred to the cleaning step without absorbing the cooling water, and the cooling The water absorption residue that has absorbed water is transferred to the landfill site.

  The present invention divides the incineration residue put into the cooling tank into the water absorption residue and the cleaning residue at a predetermined time interval.

  In the present invention, the cooling tank includes a first cooling tank and a second cooling tank provided separately, the water absorption residue is placed in the first cooling tank, and the cleaning residue is the second cooling tank. Put in the tank.

  The present invention measures the salt concentration of the cooling water in the cooling tank, and when the cooling water salt concentration in the cooling tank is less than a predetermined value, the incineration residue that has absorbed the cooling water is the cleaning step When the salt concentration of the cooling water in the cooling tank is not less than a predetermined value, the incineration residue that has absorbed the cooling water is transferred to the landfill site.

  In the present invention, the incineration residue includes main ash and fly ash generated by burning the waste, the main ash is put into the cooling tank, and the fly ash is kneaded with an insolubilizing agent, An insolubilization process is provided to stabilize heavy metals contained in the fly ash so that they do not elute.

  In the present invention, in the insolubilization step, the water separated in the waste water treatment step is kneaded into the fly ash together with the insolubilizing agent.

  The present invention controls the temperature of the incinerator by transferring the wastewater generated in the cleaning process to an incinerator that burns the waste.

  In the present invention, the waste water generated in the washing step is converted into a dry solidified salt using waste heat of the incinerator, and the dry solidified salt is transferred to the landfill disposal site.

  In the present invention, the incineration residue taken out from the cooling tank is accommodated in a container and transferred to the cleaning step.

  The cleaning step according to the present invention facilitates the incineration residue from the incineration residue by continuously venting the incineration residue while the incineration residue is housed in the container, and intermittently watering the incineration residue. Remove the eluted components.

  According to the present invention, waste water containing easily eluted components generated in the cleaning process is transferred to the cooling process and absorbed by the incineration residue. Therefore, it can suppress that the wastewater containing an easily eluted component is discharged | emitted out of a processing facility as it is.

It is a conceptual diagram of the processing equipment in which the processing method of the incineration residue of this invention is performed. It is a graph which shows the conditions of the benchmark test performed by the washing | cleaning process of this invention, and the washing | cleaning process of a comparative example. It is a graph which shows the quantity of the easily eluted component eluted from the main ash in the various washing | cleaning processes shown in FIG. It is a graph which shows the result of the washing test which confirms the effect of the washing process of the present invention. It is a graph which shows the correlation of Pb density | concentration in leachate, and Cl density | concentration, when main ash is wash | cleaned by the washing | cleaning test. It is a schematic diagram which shows the process which adjusts a liquid-solid ratio in the washing | cleaning process of this invention. In the cooling process of this invention, it is a schematic diagram explaining the process of dividing the main ash put into a cooling tank into a washing process and a landfill disposal site. In the cooling process of this invention, it is a schematic diagram explaining the process of dividing the main ash put into a cooling tank into a washing process and a landfill disposal site.

  A treatment facility in which the residue treatment method of the present invention is performed will be described with reference to the conceptual diagram of FIG. The treatment facility 10 includes an incinerator 11, an ash cooling device 12, a cleaning device 13, a wastewater treatment device 14, and an insolubilization device 15. In the incinerator 11, waste is incinerated to generate incineration residues. The incineration residue is combustible ash and includes main ash and fly ash. The main ash is discharged from the bottom of the incinerator 11, and the fly ash is collected by the dust collector along with the exhaust gas among the ash generated when the waste is incinerated.

  Further, a watering mechanism 16 for watering the incinerator 11 is provided. The watering mechanism 16 includes a sprinkler, and water can be sprinkled into the incinerator 11 from the watering mechanism 16 to adjust the temperature in the incinerator 11.

  The ash cooling device 12 is disposed below the incinerator 11 and can cool the main ash discharged from the incinerator 11. As for the ash cooling device 12, the cooling water is stored in the cooling tank 12A. Further, a supply pipe that supplies cooling water to the cooling tank 12A and a water supply pipe that drains the cooling water from the cooling tank 12A are provided. The water pipe forms a path A1 that guides a part of the cooling tank 12A to the water spray mechanism 16. Furthermore, the path | route E2 which discharges the main ash cooled with the ash cooling device 12 out of the cooling tank 12A is provided. The main ash discharged to the path E <b> 2 is transported by transport means such as a conveyor and is stored in the container 17.

  The container 17 is transferred to the cleaning device 13. The cleaning device 13 includes a cleaning tank 18 that stores main ash, a watering mechanism 19 provided above the cleaning tank 18, and an air supply mechanism 20 provided at the bottom of the cleaning tank 18. The watering mechanism 19 includes a water supply pipe connected to the water tank, a valve provided in the middle of the water supply pipe, and a sprinkler attached to an end of the water supply pipe. The upper part of the cleaning tank 18 is opened, and the water sprayed from the water spray mechanism 19 is supplied to the main ash in the cleaning tank 18. By adjusting a valve provided in the middle of the water supply pipe, the amount of water sprayed from the water spray mechanism 19 can be changed.

  The air supply mechanism 20 includes a blower that is a kind of air machine, and an air supply pipe through which air discharged from the blower outlet flows. The amount of air can be controlled by controlling the rotational speed of the blower and a valve provided in the air supply pipe. The cleaning device 13 is intermittent (intermittent) to the cleaning tank 18 so that the weight ratio between the amount of waste water after cleaning and the amount of main ash containing water, specifically, the liquid-solid ratio is 1 or less. The amount of water sprayed on the water and the amount of main ash in the cleaning tank 18 are adjusted.

  In addition, a water collection pipe is provided in the cleaning tank 18, and waste water containing easily-eluting components dispersed on the main ash and eluted from the main ash is discharged to the outside of the washing tank 18 through the water collection pipe. Furthermore, the main ash cleaned by the cleaning device 13, that is, the main ash that is removed from the easily eluted components and that discharges the main ash to the outside of the processing facility 10 is provided. Is transported to the recycling process B1 or the landfill site C1. The landfill disposal site C1 is a so-called final disposal site.

  The waste water treatment device 14 is a device that separates waste water discharged from the cleaning device 13 into easily eluted components and water. The waste water treatment device 14 simply treats the waste water discharged from the cleaning device 13 to insolubilize easily eluted components that are problematic to elution in the landfill disposal site C1, such as heavy metals such as Pb and Ca, and form sludge as waste sludge. Remove.

  In addition, the sludge newly generated in the wastewater treatment apparatus 14 insolubilizes heavy metals such as easily-dissolvable Pb, and also carbonates Ca that causes scale to change to a form that is difficult to elute and to the landfill disposal site C1. Carry in. Therefore, it greatly contributes to reducing the load on water treatment at the landfill site C1.

The wastewater treatment device 14 is not intended to drain wastewater containing easily eluted components out of the treatment facility 10 (outside of the system), but to reduce easily eluted components, such as drainage standards. It is not always necessary to clear the standard. Therefore, what is necessary is just to insolubilize or decompose | dissolve an easily eluted component from wastewater and to remove as sludge by methods, such as a coagulation sedimentation and an adsorption tower. In the wastewater treatment device 14, the easily eluted components to be removed include the items shown in the following (a) to (c).
(A) Items listed in the Judgment Criteria for Specially Controlled Industrial Waste (Flame) Mercury, cadmium, lead, hexavalent chromium, arsenic, selenium, 1,4-dioxane, dioxins (b) Abolition of final disposal site Technical standards related to leachate Control values for leachate and measurement frequency (Controlled disposal site abolition standards) Organic / nitrogen components (ammonia, nitrite, nitrate)
Boron, fluorine / copper, zinc, soluble iron, soluble Mn, SS, etc. (c) Calcium The cleaning device 13 is configured so that the water / main ash / liquid / solid ratio (weight ratio) in the wastewater base is 1 or less. The amount of main ash in the cleaning tank 18 and the amount of water sprayed from the water spray mechanism 19 are adjusted. For this reason, the wastewater treatment apparatus 14 is small and can be used. The easily eluted components removed from the waste water as sludge are conveyed to the landfill disposal site C1 via the route A3.

  The insolubilizing device 15 is a device for treating fly ash out of the incinerated ash coming out of the incinerator 11. The insolubilizing apparatus 15 is an apparatus for insolubilizing heavy metals contained in the fly ash by kneading the fly ash with a chelating agent or cement as an insolubilizing agent. The insolubilized fly ash is conveyed to the landfill disposal site C1 via the route A4.

  The cleaning process performed by the cleaning apparatus 13 in this embodiment will be specifically described. The cleaning device 13 promotes the elution of easily eluted components from the main ash by spraying water and ventilating the main ash in the cleaning tank 18. For this reason, in the cleaning device 13, the main ash is left in the cleaning tank 18, and water is sprayed downward from a water spray mechanism 19 such as a sprinkler. Sprinkling is performed intermittently, and a small amount of water is sprayed many times, so that formation of a fixed water passage (that is, a water channel) in the main ash can be suppressed. When watering is performed automatically and intermittently, a solenoid valve is used as a valve, a controller for opening and closing the solenoid valve is provided, and the controller may control the opening and closing of the solenoid valve according to the time measured by a timer. It is also possible for the operator to manually open and close the valve and spray water intermittently.

  As described above, in the cleaning device 13, the sprayed water is dispersed throughout the main ash without unevenly penetrating. Therefore, it is possible to efficiently elute easily eluted components contained in the main ash with a small amount of watering, that is, to wash out.

  FIG. 2 shows the results of a bench scale test performed to confirm the effectiveness of the cleaning device 13, that is, the experimental results of cleaning the main ash by various cleaning methods (cleaning steps). FIG. 3 shows the amounts of Na, Ca and Cl eluted from the main ash in the various cleaning methods shown in FIG. The cleaning process performed by the cleaning device 13 of the present embodiment corresponds to sprinkling / ventilation cleaning among the cleaning names shown in FIG. As for the cleaning conditions in watering and aeration cleaning, intermittent watering is performed so that the watering intensity (watering amount) per day is 148 mm. Further, the sprinkling and aeration cleaning is performed by continuously ventilating the main ash for 24 hours at a speed of 2 mm per second, that is, constantly. The liquid-solid ratio (weight ratio) between the amount of waste water after washing and the amount of main ash is set to 1 or less. In sprinkling / ventilation cleaning, the amount of intermittent watering and the amount of main ash are adjusted so that the liquid-solid ratio is in the range of 0.5 to 0.6.

  The mechanical stirring cleaning is the cleaning process of Comparative Example 1, and the cleaning conditions of the mechanical stirring cleaning are in accordance with Environment Agency Notification No. 13, and the main ash was cleaned by shaking for 6 hours at a liquid-solid ratio of 10. The immersion cleaning is a cleaning process of Comparative Example 2. The cleaning conditions for the immersion cleaning were a liquid-solid ratio of 0.6 to 1.0, and the main ash was immersed in water for 24 hours for cleaning. In FIG. 2, the liquid-solid ratio is a weight ratio between the waste water discharged from the cleaning device and the main ash after cleaning, and is a value obtained by dividing the amount of waste water by the amount of main ash.

  Comparing each washing process, the liquid-solid ratio in sprinkling / venting washing was suppressed to be smaller than the liquid-solid ratio in mechanical stirring type washing and the liquid-solid ratio in immersion washing for washing out easily-eluting salts such as Na and Cl. Moreover, it turns out that there exists a washout effect equivalent to mechanical stirring type washing | cleaning and immersion washing | cleaning. On the other hand, with regard to the amount of salt that is dependent on the liquid-solid ratio, such as Ca, watering and aeration cleaning corresponding to the cleaning device 13 of this embodiment is less than mechanical stirring cleaning.

  Thus, sprinkling and aeration cleaning corresponding to the cleaning device 13 of this embodiment is excellent in washing out salts with high efficiency with a small amount of sprinkling, but is contained in a large amount in the main ash such as Ca. Therefore, it is not suitable for washing out salt that elutes depending on the liquid-solid ratio. However, in practice, it is not practical to wash out all the Ca and the like contained in the main ash by several tens of percent. Moreover, since the load of water treatment will also be increased, it is desirable to insolubilize such components while washing out the easily-eluting portion in the initial stage.

  Next, the influence on the elution action by the presence or absence of aeration when the easily eluting components are eluted from the main ash by the cleaning device 13 will be described. FIG. 4 is a graph showing the results of a test for cleaning the main ash by the watering / venting cleaning method. In the cleaning test, main ash is accommodated in a column having an inner diameter of φ104 mm at a height of 300 mm, and the main ash is cleaned by a sprinkling / ventilation cleaning method. The main ash after washing was divided into three equal parts every 10 cm into the upper layer, middle layer, and lower layer, and the results of measuring the Cl concentration in the elution water (announcement No. 13) in the main ash of each layer are shown in FIG. Yes.

  Set the first treatment section with a sprinkling strength (sprinkling amount) of 320 mm per day and two processing sections with a sprinkling strength (sprinkling amount) of 160 mm per day, and compare each treatment section with and without aeration. went. In the first treatment section where the sprinkling strength is large, the concentration of Cl in the elution water in the middle layer is higher than in the other layers without aeration. This is presumed to be caused by the formation of water passages in the main ash. On the other hand, in the first treatment zone, the presence of aeration decreased the concentration of Cl in the elution water in the middle layer, suggesting that the formation of the water passage was eased in the main ash or that the water passage was eliminated. doing.

  On the other hand, in the second treatment zone, a normal elution tendency that the concentration of Cl in the elution water increases from the upper layer toward the lower layer regardless of the presence or absence of aeration is observed, and the watering strength is appropriate. confirmed. However, in the middle and lower layers of the second treatment zone, the concentration of Cl is lower when there is aeration than when there is aeration, suggesting the effect of promoting the washing out of Cl by aeration.

FIG. 5 is a regression line showing the correlation between the Pb concentration and the Cl concentration in the leachate when the main ash is washed by the sprinkling / ventilation washing method corresponding to the washing device 13. The leachate contains easily-eluting components and comes out of the main ash, and “leaching water” is synonymous with “waste water” coming out of the cleaning device. The Pb concentration and Cl concentration in the leachate showed a high correlation with the coefficient of determination R2 = 0.90, and it was confirmed that the readily soluble components showed the same elution tendency even with heavy metals. The determination coefficient 0.90 was calculated as follows.
y = 0.068x-562.06
R ² = 0.9053
As described above, the main ash from which the easily eluted components have been removed by the cleaning device 13 depends on the properties of the original main ash, but if the recycling standard can be satisfied by the cleaning, the cement raw material, the roadbed material, etc. Recycling to secondary concrete products such as civil engineering materials and blocks. Conventionally, if the main ash that is landfilled to the final disposal site can be cleaned and recycled by the cleaning device 13 of the present embodiment, not only will the main ash disposal cost be reduced, but also the tight final This can greatly contribute to extending the life of the disposal site.

  Even when it is difficult to recycle the main ash due to the nature of the main ash, social conditions, etc., the main ash that has been subjected to the cleaning process by the cleaning device 13 of the present embodiment is landfilled without any treatment as in the past. Compared to the case, stabilization is progressing significantly. Therefore, it can contribute to the early abolition of the disposal site.

  Further, in the cleaning device 13, water is sprayed from above the cleaning tank 18, and air is ventilated from below the main ash from the lower part of the cleaning tank 18 using an air supply mechanism 20 including a blower and the like. . The effect of aeration includes an effect of suppressing the formation of a water passage and an effect of promoting the elution of salts by CO2. In addition, in order to ensure a long contact time between the main ash and air, a cleaning time of about 1 day is required at the maximum. On the other hand, the liquid-solid ratio in the wastewater base is 1 or less, and the wastewater discharged from the cleaning process of this embodiment. The amount is less than the amount of waste water from the cleaning process of the comparative example.

  Furthermore, in this embodiment, the main ash cooled by the ash cooling device 12 is accommodated in the container 17 and conveyed to the cleaning device 13. Therefore, even if the incinerator 11 and the cleaning device 13 are located in the processing facility 10 away from each other, the main ash can be cleaned by the cleaning device 13. Moreover, the incinerator 11 and the cleaning apparatus 13 increase the degree of freedom of the installation location in the processing facility 10.

  In the present embodiment, in the cleaning device 13, the operator manually adjusts the amount of main ash carried into the cleaning device 13 and the amount of water spray so that the liquid-solid ratio in the wastewater base is 1 or less. May be. On the other hand, an example of automatically adjusting the amount of main ash carried into the cleaning device 13 and the amount of water spray to make the liquid-solid ratio in the wastewater base 1 or less will be described with reference to FIG.

  An adjustment mechanism 21 that adjusts the amount of main ash that is put into the cleaning tank 18 from the container 17 is provided. The adjustment mechanism 21 includes, for example, a weighing unit and a shutter. In the adjusting mechanism 21, the shutter is opened and closed by the controller 22, and the amount of main ash supplied to the cleaning tank 18 is controlled. Further, the controller 22 controls the valve of the watering mechanism 19 to control the amount of water sprayed on the main ash in the cleaning tank 18.

  Since the amount of wastewater generated in the cleaning device 13 of this embodiment is smaller than the amount of wastewater generated in the cleaning device of the comparative example, the wastewater treatment device 14 separates the wastewater into easily eluted components and water. Water can be transferred into the treatment facility 10. Hereinafter, the path | route which transfers the water isolate | separated with the waste water treatment apparatus 14 into the processing equipment 10 is demonstrated.

  In the treatment facility 10, the water transfer path separated by the wastewater treatment apparatus 14 includes the following first path D1 to fourth path D4.

(First route)
The water transferred through the first path D1 is put into the cooling tank 12A of the ash cooling device 12. In other words, the treatment facility 10 separates the wastewater into the easily eluted components and water by the wastewater treatment device 14, puts the separated water into the cooling tank 12A and uses it as cooling water, absorbs it into the main ash, and cleans it again. It is possible to return to the device 13. Therefore, it can suppress that wastewater is discharged | emitted out of the processing equipment 10 as it is.

  By the way, if the process of circulating the water separated by the wastewater treatment device 14 to the ash cooling device 12 and the cleaning device 13 is repeated, the salt concentration in the cooling tank 12A of the ash cooling device 12 may gradually increase. is assumed. Therefore, in the processing facility 10, the following processing can be executed in order to suppress an increase in the salt concentration in the cooling tank 12A of the ash cooling device 12.

  First, the main ash discharged from the incinerator 11 after the combustion of the waste is in a state where the moisture content is nearly 0%. On the other hand, the water content of the main ash discharged from the cooling tank 12A is 30 to 40%. This means that the main ash in the cooling tank 12A absorbs water and takes out the cooling water. Therefore, in the present embodiment, the main ash absorbs the cooling water in the cooling tank 12A using the main ash, and then at least a part of the main ash is reclaimed from the route E1 to the landfill disposal site C1. It is possible to transport it. Thus, if the main ash in the cooling tank 12A is distributed to the cleaning device 13 and the path E1, the number of times the wastewater circulates through the cleaning device 13, the wastewater treatment device 14, and the ash cooling device 12 can be reduced. It is possible to prevent the salt concentration in the ash cooling tank from increasing.

  Next, an example in which main ash carried into the ash cooling device 12 is distributed to the cleaning device 13 and the path E1 will be described.

(Distribution example 1)
As described above, the main ash having a dry water content of 0% and a weight of 1 t can absorb about 0.4 t of cooling water even if the water content can be up to 30%. On the other hand, the cleaning device 13 can clean the main ash at a liquid / solid ratio of 1 or less, specifically, at a liquid / solid ratio of about 0.5. That is, the main ash may be accommodated in the cleaning device 13 in order to reduce the amount of waste water to about 0.4 t.

  Therefore, about 1.0 t of main ash having a moisture content of 0% is discharged from the incinerator 11 to the ash cooling device 12 and about 1.4 t of cooled main ash is obtained including the cooling water in the cooling tank 12A. If about 1.4 tons of main ash containing cooling water, about 0.6 tons of main ash is taken out from the ash cooler 12 and transferred from the path E1 to the landfill disposal site C1. The distribution ratio of the main ash including the cooling water can be determined so that the 8t main ash is conveyed to the cleaning device 13. In addition, the weight of the main ash discharged | emitted from the incinerator 11 to the ash cooling device 12 can be changed arbitrarily, according to the weight of the main ash discharged from the incinerator 11 to the ash cooling device 12, the liquid-solid ratio, What is necessary is just to set the ratio which distributes the main ash absorbed with the ash cooling device 12 to the washing | cleaning apparatus 13 and the path | route E1.

  As described above, when the distribution ratio of the main ash including the cooling water is determined, the main ash having a water content of 0% that is put into the ash cooling device 12 can absorb all the water that is discharged from the waste water treatment device 14. Therefore, the treatment facility 10 of the present embodiment can reliably prevent the waste water from the cleaning device 13 from leaving the treatment facility 10 as it is.

  The process of distributing the main ash cooled by the ash cooling device 12 to the cleaning device 13 and the path E1 can be performed manually by an operator, but can also be performed automatically. A process of automatically distributing the main ash cooled by the ash cooling device 12 to the cleaning device 13 and the path E1 will be described with reference to FIG. Two paths E1 and E2 branched from the ash cooling device 12 are provided. The path E <b> 2 is connected to the conveyor and the container 17. Moreover, the distribution mechanism 23 which distributes the main ash of the ash cooling device 12 into the path | route E1 and the path | route E2 is provided. The distribution mechanism 23 has shutters that open and close the paths E1 and E2, respectively, and a controller 24 that controls the distribution mechanism 23 is provided. By controlling the opening degree of the shutter of the distribution mechanism 23 in FIG. 7, the ratio of distributing the main ash absorbed by the ash cooling device 12 to the cleaning device 13 and the path E1 can be controlled.

(Distribution example 2)
The ash cooling device 12 in the distribution example 2 refers to main ash discharged from the incinerator 11 as “main ash to be cleaned” according to time in order to take out at least a part of the cooling water in the cooling tank 12A together with the main ash. The structure is divided into “main ash that absorbs water” and cooling water is taken out by the main ash that absorbs water. For example, a first time zone for transferring all the main ash in the ash cooling device 12 to the cleaning device 13 and a second time zone for moving all the ash in the ash cooling device 12 to the path E1 are set. . The operation of distributing the main ash in the ash cooling device 12 to the cleaning device 13 and the path E1 may be performed manually, or the configuration shown in FIG. 7 may be used.

  For example, the signal of the timer 25 is input to the controller 24. The timer 25 detects a time interval corresponding to the first time zone, detects a time interval corresponding to the second time zone, and inputs these detection signals to the controller 24. Then, the controller 24 controls the shutter of the distribution mechanism 23 so as to convey all the main ash in the ash cooling device 12 to the cleaning device 13 in the first time zone. In addition, the controller 24 controls the shutter of the distribution mechanism 23 so as to transfer all the ash in the ash cooling device 12 to the path E1 in the second time zone.

(Distribution example 3)
A distribution example 3 in which the main ash carried into the ash cooling device 12 is distributed to the cleaning device 13 and the path E1 will be described with reference to FIG. The ash cooling device 12 includes cooling tanks 12B and 12C. The cooling tanks 12B and 12C are provided independently. Cooling water is put in the cooling tank 12B, and when the cooling water in the cooling tank 12B decreases, fresh water such as tap water, industrial water, and well water is supplied into the cooling tank 12B, and the cooling water corresponding to the decrease is supplied. Make up. On the other hand, the water transferred through the first path D1 is supplied to the cooling tank 12C. The cooling tank 12C is connected to the path E1. The cooling bath 12B is connected to the cleaning device 13 via the path E2. The ash cooling device 12 has a switching mechanism 26. The switching mechanism 26 includes a shutter or the like, and the switching mechanism 26 is controlled by a controller 27. The controller 27 controls the switching mechanism 26 to distribute the main ash discharged from the incinerator 11 to the cooling tank 12B or the cooling tank 12C.

(Distribution example 4)
A distribution example 4 in which the main ash carried into the ash cooling device 12 is distributed to the cleaning device 13 and the path E1 will be described with reference to FIG. In the distribution example 4, a measurement mechanism (sensor) 28 for measuring the electrical conductivity (EC) in the cooling bath 12A is provided. A signal from the measurement mechanism 28 is input to the controller 24, and the controller 24 controls the distribution mechanism 23. If the salt concentration in the cooling tank 12A is high, the electrical conductivity of the wastewater is high. If the electrical conductivity detected by the measurement mechanism 28 is less than a predetermined value, the main ash having absorbed cooling water by the ash cooling device 12 is transferred to the cleaning device 13. On the other hand, when the electrical conductivity detected by the measurement mechanism 28 is equal to or greater than the predetermined value, the main ash having absorbed the cooling water by the ash cooling device 12 is transferred to the landfill site C1 through the path E1.

  Here, the predetermined value of electrical conductivity indicates the degree of salt concentration. When the electrical conductivity of the cooling water is equal to or higher than a predetermined value, for example, “the concentration of salts remaining in the washed main ash even when the main ash containing cooling water is washed with fresh water by the cleaning device 13, Since the malfunction that it will become higher than the density | concentration of the main ash before washing | cleaning arises, the main ash which absorbed cooling water with the ash cooling device 12 is transferred to the landfill disposal site C1.

  On the other hand, when the electrical conductivity of the cooling water is less than the predetermined value, the above-described problem does not occur, and thus the water that has absorbed the cooling water by the ash cooling device 12 is transferred to the cleaning device 13. That is, the predetermined value of electrical conductivity is a threshold value for determining whether or not the main ash containing cooling water is washed by the washing device 13 to remove salts, and is stored in the memory of the controller 24 in advance. ing.

  In addition to the electrical conductivity (EC), the index for estimating the salt concentration of the cooling water in the cooling tank 12A is the cooling water ion concentration (sodium, chlorine, etc.), the cooling water density, the cooling water viscosity, and the cooling. You may use at least 1 among the absorptivity of the light in water, the refractive index of the light in cooling water, the optical rotation of cooling water, and the radiation dose of cooling water. In this case, the measurement mechanism 28 uses what can detect each index separately.

  And when at least one parameter | index detected by the measurement mechanism 28 is more than predetermined value, the main ash which absorbed cooling water with the ash cooling device 12 can be transferred to the landfill disposal site C1. . On the other hand, the main ash that has absorbed the cooling water by the ash cooling device 12 can be transferred to the cleaning device 13 when at least one of the above-described indexes is less than a predetermined value.

(Second route)
The second path D <b> 2 is a path for transferring a part of the water discharged from the wastewater treatment device 14 to the insolubilization device 15. And the insolubilizer 15 adds water, when mixing and stirring fly ash, an insoluble additive etc. (chelate, cement). If the incinerator 11 is a stoker furnace, the amount of fly ash generated is 1/3 or less of the main ash compared to other incinerators, and the salt concentration contained in the fly ash is different from that of other incinerators. Compared to 10 times higher. Therefore, when transferring the water discharged from the waste water treatment apparatus 14 to the insolubilization apparatus 15, the water is concentrated and transferred. As a concentration method, water circulation and heat concentration are effective. The circulation of water is to circulate water in a closed system including the wastewater treatment device 14, the ash cooling device 12, and the cleaning device 13. In this way, the water discharged from the wastewater treatment device 14 is transferred to the insolubilization device 15 through the second path D2. Then, water is kneaded into fly ash by the insolubilizer 15, and the fly ash kneaded with water passes through the path A4 and is conveyed to the landfill disposal site C1. Therefore, it is possible to prevent the water discharged from the waste water treatment apparatus 14 from leaving the system of the treatment facility 10 as it is.

(3rd route)
The third path D <b> 3 is a path for transporting water from the wastewater treatment device 14 to the incinerator 11. As described above, the watering mechanism 16 for spraying the cooling water in the ash cooling device 12 into the furnace is provided, and the water discharged from the wastewater treatment device 14 is sprayed into the incinerator 11 from the watering mechanism 16. It can be evaporated or used for temperature adjustment in the incinerator 11. The third path D3 may be provided alone, or the third path D3 and the water pipe that sprays the water in the ash cooling tank to the incinerator 11 are merged, and the merged water is sprayed to the incinerator 11. Also good.

(4th route)
The fourth path D4 is a path for transferring water from the wastewater treatment apparatus 14, and the water transferred through the fourth path D4 is concentrated and then introduced into the dryer 31. The water concentration method is the same as described above. The dryer 31 dries the concentrated water to obtain a dry solidified salt, and the dry solidified salt is conveyed to the landfill disposal site C1 through the path A3 together with sludge.

  Since the dried solidified salt reduces the elution of salts at the landfill disposal site C1, insolubilization treatment such as cement solidification may be performed before the dried solidified salt is transported to the landfill disposal site C1. Furthermore, an efficient treatment system can be obtained by utilizing the waste heat of the incinerator 11 for the drying treatment of the water performed in the dryer 31. As the heat transport system 32 for transporting the waste heat of the incinerator 11 to the dryer 31, for example, a pipe for transporting steam, a heat pipe, a pipe or a container containing a latent heat storage material can be used.

  In the present embodiment, since the cleaning device 13 is independent of the incinerator 11, the cleaning device 13 does not need to be installed in a place adjacent to the incinerator 11, and is cleaned in a vacant space in the site of the existing incineration facility. The device 13 can be installed. Therefore, there is almost no need to change the specifications of the existing incinerator 11 in order to provide the cleaning device 13. Therefore, the cleaning device 13 can be installed without affecting the operation of the incinerator 11.

  However, when the cleaning device 13 is installed in a place away from the incinerator 11, the water after being separately treated by the waste water treatment device 14 is transferred to the incinerator 11 via the third path D3 by a vacuum car or a pump. Need to be transported. In addition, since the intermittent water spray control in the cleaning device 13 is very simple, maintenance of the machine constituting the cleaning device 13 and a large amount of man-hours are not required for the cleaning work, and the burden on the incineration facility staff is small. Further, in the first route D1 to the third route D3, which of pipes, containers, trucks, etc. is used as the transport means for transporting water is selected in consideration of the amount of water, the distance between the facilities, and the like. That's fine.

  In the treatment facility 10 of the present embodiment, the main ash and fly ash correspond to the incineration residue of the present invention, and the process performed in the incinerator 11 is the incineration process of the present invention, and the process performed in the ash cooling device 12. Is the cooling process of the present invention, the process performed in the cleaning device 13 is the cleaning process of the present invention, the process performed in the waste water treatment apparatus 14 is the waste water treatment process of the present invention, and the insolubilization apparatus 15 The treatment to be performed is the insolubilization step of the present invention. The process performed in the processing facility 10 is the processing method of the present invention. 8 corresponds to the first cooling tank of the present invention, and the cooling tank 12B of FIG. 8 corresponds to the second cooling tank of the present invention. Further, in FIGS. 7 and 8, the main ash transferred to the cleaning device 13 corresponds to the cleaning residue in the present invention, and the main ash transferred to the landfill disposal site C1 corresponds to the water absorption residue in the present invention. To do.

  The cooling process of the present invention cools the incineration residue using at least part of the water discharged from the wastewater treatment process. In the treatment method of the present invention, the entire incineration residue that has absorbed cooling water in the cooling step is transferred to the washing step, the incineration residue that has absorbed cooling water in the cooling step is transferred to the washing step, and It is possible to selectively switch between the process of transferring a part to the landfill site and the process of transferring all of the incineration residue that has absorbed the cooling water in the cooling process to the landfill site. That is, the processing apparatus of the present invention may not transfer all of the incineration residue transferred from the incineration process to the cooling process to the cleaning apparatus.

  Further, the treatment facility 10 of the present invention transfers all of the water discharged from the wastewater treatment device 14 to the ash cooling device 12 and transfers a part of the water discharged from the wastewater treatment device 14 to the ash cooling device 12. The process of transferring the remainder to at least one of the insolubilizer 15 or the incinerator 11 can be switched.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. For example, incineration residues are those that remain after incineration of waste in an incinerator. In addition to ash (main ash, fly ash) generated by combustion of combustible materials, combustible materials remain unburned and incombustible materials. Including. In FIG. 1, the wastewater generated in the cleaning device 13 is bypassed by the wastewater treatment device 14 and concentrated in the fourth path D4, and dried in the dryer 31 to obtain a dry solidified salt. It is also possible to transport to the landfill disposal site C1 via the route A3 together with the sludge. Furthermore, the container 17 can be used as the cleaning tank 18 in the cleaning process. That is, the main ash is ventilated and intermittently watered while being accommodated in the container 17.

DESCRIPTION OF SYMBOLS 10 Treatment equipment 11 Incinerator 12 Ash cooling device 12A, 12B, 12C Cooling tank 13 Cleaning device 14 Wastewater treatment device 15 Insolubilization device

Claims (14)

An incineration residue treatment method for treating incineration residue generated by combustion of waste,
A cooling step of cooling the incineration residue by putting the incineration residue into a cooling tank containing cooling water;
A washing step of continuously ventilating the incineration residue taken out from the cooling tank, and intermittently watering the incineration residue to remove easily eluted components from the incineration residue,
Have
A method for treating incineration residue, wherein waste water generated by washing the incineration residue in the washing step is used as cooling water to be put into the cooling tank. In the processing method of the incineration residue of Claim 1,
Before putting the wastewater into the cooling tank, a wastewater treatment step is provided to separate the wastewater into the easily eluted components and water,
A method for treating an incineration residue, wherein the water separated in the waste water treatment step is used as cooling water to be put into the cooling tank. In the processing method of the incineration residue of Claim 2,
In the washing step, the amount of the incineration residue to be washed and the amount of water spray are adjusted so that the liquid-solid ratio between the waste water generated by washing the incineration residue and the incineration residue after washing is 1 or less. Set the incineration residue treatment method. In the processing method of the incineration residue of Claim 3,
A method for treating incineration residue, wherein the incineration residue that has absorbed the cooling water in the cooling tank is transferred to a landfill site. In the processing method of the incineration residue of Claim 4,
The incineration residue put into the cooling tank is divided into a water absorption residue that absorbs the cooling water and a cleaning residue that is transferred to the cleaning step without absorbing the cooling water,
A method for treating incineration residue, wherein the residue for absorbing water that has absorbed the cooling water is transferred to the landfill site. In the processing method of the incineration residue of Claim 5,
A method for treating an incineration residue, wherein the incineration residue placed in the cooling tank is divided into the water absorption residue and the cleaning residue at a predetermined time interval. In the processing method of the incineration residue of Claim 5,
The cooling tank includes a first cooling tank and a second cooling tank provided separately,
The method for treating an incineration residue, wherein the residue for water absorption is placed in the first cooling tank, and the residue for washing is placed in the second cooling tank. In the processing method of the incineration residue of Claim 4,
Measure the salt concentration of cooling water in the cooling tank,
When the salt concentration of the cooling water in the cooling tank is less than a predetermined value, the incineration residue that has absorbed the cooling water is transferred to the cleaning step,
When the salt concentration of the cooling water in the cooling tank is a predetermined value or more, the incineration residue processing method of transferring the incineration residue that has absorbed the cooling water to the landfill site. In the processing method of the incineration residue of any one of Claims 2-8,
The incineration residue includes main ash and fly ash generated by burning the waste,
The main ash is put into the cooling tank,
A method for treating an incineration residue, wherein an insolubilizing step is provided in which an insolubilizing agent is kneaded in the fly ash and stabilized so that heavy metals contained in the fly ash are not eluted. In the processing method of the incineration residue of Claim 9,
The insolubilization step is a method for treating an incineration residue in which the water separated in the waste water treatment step is kneaded into the fly ash together with the insolubilizing agent. In the processing method of the incineration residue of any one of Claims 1-10,
A method for treating an incineration residue, wherein the waste water generated in the washing step is transferred to an incinerator for burning the waste to adjust the temperature of the incinerator. In the processing method of the incineration residue of any one of Claims 1-10,
A method for treating an incineration residue, wherein the waste water generated in the washing step is converted into a dry solidified salt using waste heat of the incinerator, and the dry solidified salt is transferred to the landfill disposal site. In the processing method of the incineration residue of any one of Claims 1-11,
A method for treating incineration residue, wherein the incineration residue taken out from the cooling bath is accommodated in a container and transferred to the cleaning step. In the processing method of the incineration residue of Claim 13,
In the cleaning step, the incineration residue is housed in the container, and the incineration residue is continuously vented, and water is intermittently sprinkled on the incineration residue to remove easily eluted components from the incineration residue. Incineration residue treatment method to be removed.

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