JP2001321768A - Method and device for treating leachate from waste landfill site - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detoxify leachate from a waste landfill site, and to separate and refine NaCl salt and KCl salt of high purity. SOLUTION: The leachate generated in a landfill site 10 of waste such as residues of a waste incinerator or an ash melting furnace 10 is introduced into a reverse osmosis membrane filter 28 to be filtered. The permeate of the reverse osmosis membrane filter is discharged, and the concentrate of the reverse osmosis membrane filter is introduced into a nano-filtration(NF) device 16 to be filtered. The concentrate of the NF device is returned to the waste incinerator or the ash melting furnace 10 to thermally decompose toxic substances in the concentrate. After the permeate of the NF device is introduced into a chelate adsorption tower 18 to be subjected to chelate adsorption treatment, it is heated in a heating type crystallizer 38 to crystallize NaCl salt and then is cooled in a cooling type crystallizer 44 to crystallize KCl salt.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the incineration residue of a waste incinerator for incinerating waste such as municipal waste and the melting residue (slag) of an ash melting furnace for melting waste incineration ash into slag. When disposing of waste such as landfill, detoxify the leachate from the landfill site (site) and
TECHNICAL FIELD The present invention relates to a method and an apparatus for separating l and KCl by utilizing a difference in temperature melting characteristics to obtain a harmless purified salt of NaCl and a purified salt of KCl with high purity.

[0002]

2. Description of the Related Art As a method for treating leachate from a waste landfill site, for example, Japanese Patent Application Laid-Open No. H11-304131 discloses a method for pretreating leachate from a landfill site, followed by a reverse osmosis membrane filtration device, Into a drying / sintering furnace to evaporate water, and then quenched to obtain by-product salt (dry salt). A technique is described in which dioxins and environmental hormones contained in exhaust gas are decomposed by contact with an oxidation catalyst, or are introduced into an activated carbon packed column to adsorb and remove the dioxins and environmental hormones.

[0003]

SUMMARY OF THE INVENTION The above-mentioned Japanese Patent Application Laid-Open No. 11-3 is disclosed.
The dry salt formed in the process described in EP-A-04131 generally contains about 95% in total of NaCl and KCl, each content being about 60-80% for NaCl and about 20% for KCl.
~ 30%. Here, the purity of NaCl of rock salt generally imported by each chemical maker as an industrial salt is 96 to 97%. Similarly, KCl salts and KCl fertilizers imported by chemical manufacturers have a purity of 95 to 98%. Therefore,
The dry salt generated from the leachate at the landfill site requires pretreatment and is costly in order to be directly used by each chemical manufacturer. That is, it is difficult to recycle the dried salt.

[0004] The present invention has been made in view of the above-mentioned points, and an object of the present invention is to filter a landfill leachate by a reverse osmosis membrane filtration device and treat the concentrated water with a heating type crystallizer and a cooling type. Applying a crystallizer, utilizing the difference in solubility of NaCl and KCl in water, separating and purifying high-purity NaCl salt and KCl salt, dioxins contained in concentrated water of reverse osmosis membrane filtration device, Environmental hormones are separated by an NF filtration device or an electrodeposition device and introduced into a pyrolysis furnace, an incinerator or / and an ash melting furnace to be decomposed, or decomposed by an accelerated oxidation treatment device, or formed salt. The present invention provides a method and an apparatus for treating leachate from a waste landfill disposal site, wherein leachate is decomposed in a thermal decomposition furnace.

[0005]

In order to achieve the above object, a method for treating leachate from a landfill according to the present invention comprises:
Leachate generated at the landfill site of waste such as residue from a waste incinerator or / and ash melting furnace is introduced into a reverse osmosis membrane (RO membrane) filtration device and filtered. The water is discharged, the concentrated water of the reverse osmosis membrane filtration device is introduced into an NF (nano filter) filtration device and filtered, and the concentrated water of the NF filtration device is returned to a waste incinerator or / and an ash melting furnace to be concentrated. It is configured to thermally decompose harmful substances in water and chelate the permeated water of the NF filtration device, then heat to crystallize NaCl salts, and then cool to crystallize KCl salts. (See FIG. 1). The NF ^{(nanofiltration), Na +, K +,} Cl - ratio of blocking to adopt a selective low.

Further, the method for treating leachate from a landfill of a waste landfill according to the present invention uses a reverse osmosis membrane for leachate generated at a landfill site for waste such as a residue from a waste incinerator or / and ash melting furnace. It is introduced into the filtration device and filtered, the permeated water of the reverse osmosis membrane filtration device is discharged, the concentrated water of the reverse osmosis membrane filtration device is introduced into the NF filtration device and filtered, and the concentrated water of the NF filtration device is subjected to a pyrolysis furnace. To remove the harmful substances in the concentrated water by thermal decomposition.
It is characterized in that the Cl salt is crystallized and then cooled to crystallize the KCl salt (see FIG. 2).

[0007] The method for treating leachate from a landfill of a waste landfill according to the present invention is a method for treating leachate generated at a landfill site of a waste such as a residue of a waste incinerator or / and ash melting furnace with a reverse osmosis membrane. It is introduced into a filtration device for filtration, the permeated water of the reverse osmosis membrane filtration device is discharged, and the concentrated water of the reverse osmosis membrane filtration device is introduced into an electrodeposition device (electrodialysis device) for electrodeposition treatment. Is returned to a waste incinerator and / or an ash melting furnace to thermally decompose harmful substances in the concentrated water. On the other hand, the permeated water from the electrodeposition apparatus is subjected to chelate adsorption treatment and then heated to crystallize NaCl salts. It is characterized by crystallizing and then cooling to crystallize the KCl salt (see FIG. 3).

Further, the method of the present invention for treating leachate from a waste landfill site is a method for removing leachate generated at a landfill site for waste such as a residue from a waste incinerator or / and ash melting furnace by a reverse osmosis membrane. It is introduced into the filtration device to be filtered, the permeated water of the reverse osmosis membrane filtration device is discharged, and the concentrated water of the reverse osmosis membrane filtration device is introduced into the accelerated oxidation treatment device to decompose harmful substances. After the treated water is subjected to chelate adsorption treatment, it is heated to NaCl
It is characterized in that the salt is crystallized and then cooled to crystallize the KCl salt (see FIG. 4).

Further, the method of the present invention for treating leachate at a landfill site is a method for removing leachate generated at a landfill site of a waste such as a residue of a waste incinerator or / and ash melting furnace with a reverse osmosis membrane. After being introduced into the filtration device and filtered, the permeated water of the reverse osmosis membrane filtration device is discharged, and the concentrated water of the reverse osmosis membrane filtration device is subjected to chelate adsorption treatment, then heated to crystallize the NaCl salt, and then cooled. The KCl salt is crystallized, and the crystallized NaCl salt is introduced into a pyrolysis furnace to thermally decompose harmful substances, and the crystallized KCl salt is introduced into the pyrolysis furnace in a separate system from the NaCl salt to cause harmful substances. Is thermally decomposed (see FIG. 5).

[0010] In these methods, the wastewater after cooling and crystallizing the KCl salt may be circulated to the NaCl salt crystallization step (see FIGS. 1 to 5). Also, cool down and KC
In some cases, a part of the waste water after the crystallization of the 1 salt is circulated to the crystallization step of the NaCl salt, and the remainder is dried (see FIG. 6). In some cases, the waste water after cooling and crystallization of the KCl salt is completely dried (see FIG. 6). Furthermore, a part of the waste water after cooling to crystallize the KCl salt may be circulated to the NaCl salt crystallization step, and the remainder may be thermally decomposed (see FIG. 7).

An apparatus for treating leachate from a waste landfill site according to the present invention is a reverse leachate for filtering leachate generated at a landfill site for waste, such as residues from a waste incinerator or / and ash melting furnace. An osmosis membrane filtration device, an NF filtration device for filtering concentrated water of a reverse osmosis membrane filtration device, a chelate adsorption tower for performing chelate adsorption treatment on permeated water of the NF filtration device, and a concentrated water of the NF filtration device are discarded. A concentrated water return line for supplying to a material incinerator or / and an ash melting furnace, a heated crystallization apparatus for heating treated water from a chelate adsorption tower to crystallize NaCl salts, and a heated crystallization Cool the treated water of the device to KCl
A cooling type crystallizer for crystallizing a salt is provided (see FIG. 1).

Further, the apparatus for treating leachate of a waste landfill site according to the present invention is for filtering leachate generated at a landfill site of waste such as a residue of a waste incinerator or / and ash melting furnace. A reverse osmosis membrane filtration device, an NF filtration device for filtering concentrated water of the reverse osmosis membrane filtration device, a chelate adsorption tower for performing chelate adsorption treatment on permeated water of the NF filtration device,
A pyrolysis furnace for introducing concentrated water from an F filtration device to thermally decompose harmful substances, a heating type crystallization device for heating treated water from a chelate adsorption tower to crystallize NaCl salts, and a heating type A cooling type crystallizer for cooling the treated water of the crystallizer to crystallize the KCl salt is provided (see FIG. 2).

[0013] The apparatus for treating leachate from a landfill of a waste landfill according to the present invention is for filtering leachate generated at a landfill site for waste such as a residue from a waste incinerator or / and ash melting furnace. A reverse osmosis membrane filtration device, an electrodeposition device (electrodialysis device) for electrodeposition treatment of concentrated water of the reverse osmosis membrane filtration device, and a chelate adsorption tower for chelate adsorption treatment of permeated water of the electrodeposition device. A concentrated water return line for supplying concentrated water from an electrodeposition apparatus to a waste incinerator and / or an ash melting furnace, and a heating type for heating treated water from a chelate adsorption tower to crystallize NaCl salts. It is characterized by comprising a crystallizer and a cooling type crystallizer for cooling treated water of the heating type crystallizer to crystallize a KCl salt (see FIG. 3).

[0014] Further, the apparatus for treating leachate of a waste landfill site according to the present invention is for filtering leachate generated at a landfill site of a waste such as a residue of a waste incinerator or / and ash melting furnace. Reverse osmosis membrane filtration device, accelerated oxidation treatment device for introducing concentrated water of reverse osmosis membrane filtration device to decompose harmful substances, and chelate adsorption for chelating adsorption treatment of the treated water of the accelerated oxidation treatment device Tower, a heated crystallization device for heating the treated water from the chelate adsorption tower to crystallize the NaCl salt, and a cooling for cooling the treated water of the heated crystallizer to crystallize the KCl salt. And a type crystallizer (see FIG. 4).

Further, the apparatus for treating leachate from a landfill site according to the present invention is for filtering leachate generated at a landfill site for waste such as residues from a waste incinerator or / and ash melting furnace. Reverse osmosis membrane filtration device, a chelate adsorption tower for performing chelate adsorption treatment of concentrated water of the reverse osmosis membrane filtration device, and a heating type crystal for heating the treated water from the chelate adsorption tower to crystallize NaCl salts. A crystallizer, a cooling type crystallizer for cooling treated water of a heating type crystallizer to crystallize a KCl salt, and introducing a NaCl salt from a heating type crystallizer to thermally decompose harmful substances. And another pyrolysis furnace for introducing KCl salts from a cooling crystallization apparatus to pyrolyze harmful substances (see FIG. 5).

In these apparatuses, the chelate-adsorbed treated water at the drain outlet of the cooling type crystallizer and the inlet side of the heating type crystallizer so that the waste water from the cooling type crystallizer can be circulated to the heating type crystallizer. In some cases, the pipe is connected to the pipe by a drain return pipe (see FIGS. 1 to 5). Also, the drainage outlet of the cooling type crystallizer and the chelate adsorption treated water conduit on the inlet side of the heating type crystallizer are connected so that part of the wastewater from the cooling type crystallizer can be circulated to the heating type crystallizer. In some cases, a dryer is provided downstream of the cooling type crystallizer so as to be connected by a drainage return conduit and to dry the rest of the drainage (see FIG. 6).
Further, a dryer may be provided downstream of the cooling type crystallizer so that the entire amount of the wastewater from the cooling type crystallizer can be dried (see FIG. 6). Furthermore, the drainage outlet of the cooling type crystallizer and the chelate adsorption treated water conduit on the inlet side of the heating type crystallizer are connected so that part of the wastewater from the cooling type crystallizer can be circulated to the heating type crystallizer. In some cases, the drainage pipe is connected to a pyrolysis furnace so that the wastewater can be thermally decomposed by connecting the drainage return conduit and the rest of the wastewater (see FIG. 7).

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below, but the present invention is not limited to the following embodiments and can be implemented with appropriate modifications. FIG. 1 shows a waste landfill leachate treatment apparatus according to a first embodiment of the present invention. Reference numeral 10 denotes an incinerator or ash melting furnace, and the residue (incineration residue or molten residue) discharged from the furnace 10 is transported to a landfill disposal site 12. FIG. 1 shows a case where refuse is processed as an example of incineration.

A plastic impermeable sheet is laid on the landfill site 12, and leachate is extracted by a water collection pipe provided on the impermeable sheet. This leachate is introduced into the pretreatment device 14 to remove a part of heavy metals, calcium and the like in the leachate. As the pretreatment device 14, for example, a coagulation sedimentation tank using a lime soda method is used. The pretreated leachate is introduced into a reverse osmosis membrane (RO membrane) filtration device 28 and filtered, and the permeated water is discharged, and the concentrated water is introduced into the NF filtration device 16 and is mainly monovalent ions. Na ⁺ , K ⁺ , and Cl ^- are recovered on the permeate side.

Reverse osmosis membranes are semipermeable membranes that can be filtered at the molecular level when a pressure higher than the osmotic pressure is applied.
In addition to nitrogen, salts such as calcium, sodium, and potassium, dioxins, environmental hormones (for example, bisphenol A, organic chlorinated substances, etc.), heavy metals, and the like can be separated into the concentrate. The NF filtration device 16 is a device provided with a nanofilter (NF) as a permeable membrane.
In this device 16, the salts in the leachate, particularly salts of divalent or higher negative ions, can be removed to the concentrated water side by the NF membrane, and most of the organic substances can be removed to the concentrated water side. In the separation of ions by NF, not only anions but also cations can be captured in the concentrated water side with divalent or higher ions. Conceptually, the separation tendency is as follows. Actually, since various tendencies are observed depending on the material of the film, the charge thereof, and the combination, the following is not always the case. Cation Permeated water side Na ⁺ , K ⁺ Concentrated water side Ca ²⁺ , Mg ²⁺ , Fe ³⁺ , Mn ⁴⁺ , Pb ²⁺ and other heavy metals Anions Permeated water side Cl ⁻ , NO ₃ ⁻ , F ⁻ Concentrated water side SO ₄ ^2- , CO ₃ ^2- , BO ₃ ^3- Others Permeated water side Concentrated water side Dioxins, environmental hormones, SiO ₂

The permeated water (filtrate) from the NF filtration device 16 is introduced into a chelate adsorption tower 18 to remove boron, fluorine, trace heavy metals and the like. As the chelating agent, a polymer resin having a functional group such as an imino diacetic acid type, an amino phosphoric acid type, an amidoxime type, a glucamine type, a special metal supporting type, a polyamine type, a thiourea type, and a dithiocarbamic acid type is used. Can be Due to these treatments, the chelated water contains very little impurities and harmful substances, NaC
It becomes treated water containing salts mainly composed of 1 and KCl.

The concentrated water of the NF filter 16 contains divalent ions and components larger than the divalent ions, mainly harmful substances such as high molecular organic substances, dioxins, environmental hormones, and heavy metals. This concentrated water is condensed by the concentrated water return line 20.
The wastewater from the incinerator or the ash melting furnace 10 is sent to the wastewater treatment device 22 together with the wastewater, and after being treated there, returned to the incinerator or the ash melting furnace 10 and sprayed into the furnace to remove harmful substances such as dioxins. Decomposes by thermal decomposition. As the discharge treatment device 22, a two-stage coagulation sedimentation treatment + sand filtration treatment system, a coagulation sedimentation treatment + sand filtration treatment + activated carbon adsorption treatment system, or a coagulation sedimentation treatment + biological treatment + coagulation sedimentation treatment + sand filtration treatment + Chelating treatment + Activated carbon treatment system and the like are used.

The treated water subjected to the chelate adsorption treatment is supplied to the heater 3
After heating in step 4, NaCl crystallizes in the crystallization tank 36.
Next, the wastewater from the crystallization tank 36 is cooled by the cooler 40, and then KCl is crystallized in the crystallization tank 42. In this case, the heating type crystallizer 38 is constituted by the heater 34 and the crystallization tank 36,
The cooling type crystallizer 44 is composed of the cooler 40 and the crystallization tank 42. The drainage outlet 46 of the cooling type crystallizer 44 and the chelate adsorption treated water conduit 48 on the inlet side of the heating type crystallizer 38 are connected through a drainage return conduit 50, and circulate the discharge to recover NaCl and KCl. It is configured to improve the rate. The incineration or ash melting facility 24 includes the incinerator or ash melting furnace 10, the discharge treatment device 22, and the like, and the waste landfill facility 26 includes the landfill disposal site 12, the pretreatment device 1
4. Reverse osmosis membrane filtration device 28, NF filtration device 16, chelate adsorption tower 18, heating type crystallizer 38, cooling type crystallizer 4.
4 and the like. The effluent of the cooling type crystallizer 44 is returned to the heating type crystallizer 38 and / or circulated again and / or reheated as described later to produce a dry salt.

The principle of the method of separating NaCl and KCl in the series of crystallizers 38 and 44 is as shown in FIG. 8, in which a heating operation is performed by utilizing a difference in solubility in each water, and then a cooling operation is performed. Go and crystallize. First, in the heating type crystallizer 38, water is evaporated at about 100 to 110 ° C. until just before KCl reaches the saturation solubility, and NaCl is simultaneously precipitated. Next, in the cooling type crystallizer 44, about 10 to 2
After cooling to 0 ° C., for example, about 20 ° C., KCl is precipitated, and the waste water is returned to the heating type crystallizer 38. In this way, each is purified into high-purity NaCl salt and high-purity KCl salt.

FIG. 2 shows a waste landfill leachate treatment apparatus according to a second embodiment of the present invention. In the present embodiment, the concentrated water from the NF filtration device 16 is introduced into the thermal decomposition furnace 52 to thermally decompose harmful substances such as dioxins and environmental hormones to render them harmless. As the thermal decomposition furnace 52, a kiln type indirect heating furnace, a screw extrusion type indirect heating furnace, a melting furnace, or the like in a reducing atmosphere or an oxidizing atmosphere is used. Since the crude salt from the pyrolysis furnace 52 contains heavy metals, it is discarded. In the present embodiment, the waste landfill facility 26a is the landfill site 1
2, pretreatment device 14, reverse osmosis membrane filtration device 28, NF filtration device 16, chelate adsorption tower 18, heating type crystallizer 38,
The cooling type crystallizer 44, the thermal decomposition furnace 52 and the like are provided. Other configurations and operations are the same as those in the first embodiment.

FIG. 3 shows a waste landfill leachate treatment apparatus according to a third embodiment of the present invention. The present embodiment uses an electrodeposition device 54 instead of the NF filtration device 16 in the first embodiment. 20a is a concentrated water return line. The electrodeposition apparatus 54, and Na ⁺ and K ⁺ selective transmittance high cation exchange membrane, Cl ^- and place a selected high transmittance anion exchange membranes are alternately provided an anode and a cathode at each end structure Alternatively, a structure having a combination of ion exchange membranes is used. In the present embodiment, the waste landfill facility 26b is the landfill site 12, the pretreatment device 1
4. It comprises a reverse osmosis membrane filtration device 28, an electrodeposition device 54, a chelate adsorption tower 18, a heating type crystallizer 38, a cooling type crystallizer 44, and the like. Other configurations and operations are the same as those in the first embodiment.

FIG. 4 shows a waste landfill leachate treatment apparatus according to a fourth embodiment of the present invention. In the present embodiment, an accelerated oxidation treatment device 56 is used instead of the NF filtration device 16 in the first embodiment. As the accelerated oxidation treatment device 56, a device having a combination of an ozone gas-liquid contact device, an ultraviolet irradiation device, a hydrogen peroxide injection device, a catalyst filling device, and the like is used. In the present embodiment, the waste landfill facility 26c is the landfill site 1
2. Pretreatment device 14, reverse osmosis membrane filtration device 28, accelerated oxidation treatment device 56, chelate adsorption tower 18, heated crystallization device 3.
8, the cooling type crystallizer 44 and the like. Other configurations and operations are the same as those in the first embodiment.

FIG. 5 shows a waste landfill leachate treatment apparatus according to a fifth embodiment of the present invention. In the present embodiment, the concentrated water from the reverse osmosis membrane filtration device 28 is introduced into the chelate adsorption tower 18 without providing the NF filtration device 16 in the first embodiment, and contains the water from the heating type crystallizer 38. NaCl is introduced into the pyrolysis furnace 58 to thermally decompose harmful substances such as dioxins and environmental hormones contained in the NaCl to make them harmless, and to convert KCl containing water from the cooling type crystallizer 44 into the pyrolysis furnace 60. KCl
The thermal decomposition of harmful substances such as dioxins and environmental hormones contained in water is made harmless. As the thermal decomposition furnaces 58 and 60, a kiln type indirect heating furnace, a screw extrusion type indirect heating furnace, a melting furnace, or the like in a reducing atmosphere or an oxidizing atmosphere is used. In the present embodiment, the waste landfill facility 26d includes the landfill site 12, the pretreatment device 14, the reverse osmosis membrane filtration device 28, and the chelate adsorption tower 1
8, a heating type crystallizer 38, a cooling type crystallizer 44, pyrolysis furnaces 58 and 60, and the like. Other configurations and operations are the same as those in the first embodiment.

FIG. 6 shows a waste landfill leachate treatment apparatus according to a sixth embodiment of the present invention. This embodiment is different from the first embodiment in that a dryer 62 is provided downstream of the cooling type crystallizer 44.
The wastewater from 4 is configured so that the whole amount is returned or circulated, or a part is returned and circulated, and the rest is dried or the whole amount is dried. In this embodiment,
The waste landfill facility 26e includes a landfill site 12, a pretreatment device 14, a reverse osmosis membrane filtration device 28, an NF filtration device 16, a chelate adsorption tower 18, a heating type crystallizer 38, a cooling type crystallizer 44, and a dryer. 62 and the like. Of course, the present embodiment can be applied to the second to fifth embodiments.

FIG. 7 shows a waste landfill leachate treatment apparatus according to a seventh embodiment of the present invention. This embodiment is configured to recirculate a part of the wastewater from the cooling type crystallizer 44 in the second embodiment, and introduce the remaining part into the pyrolysis furnace 52 for pyrolysis. is there. In this embodiment, the waste landfill facility 26f includes the landfill site 12, the pretreatment device 14, the reverse osmosis membrane filtration device 28,
It comprises an NF filtration device 16, a chelate adsorption tower 18, a heating type crystallizer 38, a cooling type crystallizer 44, a pyrolysis furnace 52, and the like. Of course, the present embodiment can be applied to the first, third to fifth embodiments.

[0030]

EXAMPLES Examples are shown below to further clarify the features of the present invention. Example 1 After pre-treating leachate from a landfill site as follows:
The following experiment was performed. (1) Pretreatment Add sodium carbonate, sodium hydroxide, ferric chloride, polymer flocculant, and sodium hypochlorite to the leachate, stir and mix to form flocculated floc and allow to stand. The supernatant water was collected. This was neutralized with hydrochloric acid and filtered with a UF filtration device. Next, the filtrate was concentrated to a salt concentration of about 7% by removing water with an evaporator to obtain RO concentrated water. (2) Experimental method RO concentrated water was boiled in a 110 ° C. atmosphere to remove water and to crystallize NaCl. At this time, KC
The evaporation amount of water was adjusted so that the concentration of 1 did not reach the analysis value of each ion concentration and the saturated concentration of KCl previously obtained from the equilibrium calculation. The crystallized product was subjected to suction filtration and evaporated to dryness to obtain Sample A. Next, the remaining waste water was cooled and stirred at 20 ° C. The crystallized product crystallized at this time was subjected to suction filtration to obtain Sample B. (3) Experimental results (analytical results) Sample A: NaCl content 96.08% KCl content 1.07%, other 2.85% Sample B: NaCl content 1.97% KCl content 96.63%, Others 1.40% These indicate that these are comparable to the purity of NaCl and KCl imported by each chemical manufacturer.

[0031]

As described above, the present invention has the following effects. (1) When producing dry salt from reverse osmosis membrane filtration concentrated water from landfill leachate, the purity is increased to the same level as that of imported salt by applying a heating type crystallizer and a cooling type crystallizer. ,
For example, NaCl salt and KCl salt each having a purity of 96% or more can be separated and purified. For this reason, it is easier to reuse than a dry salt in which both are mixed and have a large amount of impurities such as heavy metals, as in the related art. The former can be used for soda industry as industrial salt, and the latter can be used for industrial use or fertilizer. (2) Dioxins, environmental hormones, etc. contained in the reverse osmosis membrane filtration concentrated water are separated or decomposed by the NF filtration device, the electrodeposition device, the accelerated oxidation treatment device, or the pyrolysis furnace. There is no. (3) The heavy metal contained in the reverse osmosis membrane filtration concentrated water is
Since the water is separated and removed by a filtration device, an electrodeposition device or a chelate adsorption tower, the amount mixed into the purified salt can be reduced. (4) Since fluorine, boron, and trace amounts of heavy metals contained in the concentrated water from the reverse osmosis membrane filtration are separated and removed by the chelate adsorption tower, the amount mixed with the purified salt can be reduced. (5) Cogeneration of power generation and waste heat utilization can be achieved by a temperature controller, a filtration device, an electrodeposition device, an accelerated oxidation treatment device, and a pyrolysis furnace of each crystallizer.

[Brief description of the drawings]

FIG. 1 is a systematic schematic configuration diagram showing an apparatus for treating leachate at a landfill site according to a first embodiment of the present invention.

FIG. 2 is a systematic schematic configuration diagram showing an apparatus for treating leachate at a landfill site according to a second embodiment of the present invention.

FIG. 3 is a systematic schematic configuration diagram showing a treatment device for leachate from a landfill waste disposal site according to a third embodiment of the present invention.

FIG. 4 is a systematic schematic configuration diagram showing an apparatus for treating leachate at a landfill site according to a fourth embodiment of the present invention.

FIG. 5 is a systematic schematic configuration diagram showing an apparatus for treating leachate at a landfill site according to a fifth embodiment of the present invention.

FIG. 6 is a systematic schematic configuration diagram showing an apparatus for treating leachate at a landfill site according to a sixth embodiment of the present invention.

FIG. 7 is a systematic schematic configuration diagram showing an apparatus for treating leachate at a landfill site according to a seventh embodiment of the present invention.

FIG. 8 is a graph showing saturation solubility curves of NaCl and KCl.

[Explanation of symbols]

Reference Signs List 10 incinerator or ash melting furnace 12 landfill disposal site 14 pretreatment device 16 NF filtration device 18 chelate adsorption tower 20, 20a concentrated water return line 22 wastewater treatment device 24 incineration or ash melting facility 26, 26a, 26b, 26c, 26d, 26e, 26
f Waste landfill facility 28 Reverse osmosis membrane filtration device 34 Heater 36, 42 Crystallization tank 38 Heating crystallization device 40 Cooler 44 Cooling crystallization device 46 Drainage outlet 48 Chelate adsorption treatment water conduit 50 Drainage return conduit 52 , 58, 60 Pyrolysis furnace 54 Electrodeposition device 56 Accelerated oxidation treatment device 62 Dryer

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B01D 9/02 619 B01D 9/02 619A C02F 1/00 C02F 1/00 L 1/04 ZAB 1/04 ZABZ 1/58 1/58 HM 1/62 1/62 Z 9/00 502 9/00 502A 502E 502F 502H 503 503C 503G 504 504B 504E (72) Inventor Hiromasa Kusuda 1-1-1, Kawasakicho, Akashi-shi, Hyogo Kawasaki Inside the Heavy Industries, Ltd. Akashi Factory (72) Inventor Kozo Nagayase 1-1, Kawasaki-cho, Akashi-shi, Hyogo Prefecture Kawasaki Heavy Industries, Ltd. Akashi Factory F-term (reference) 4D006 GA03 GA06 KA02 KA52 KA54 KA57 KA72 KB12 KB13 KB30 KD03 KD08 MA40 PB08 PB20 PB23 PB27 PB28 PB70 4D034 AA26 AA27 BA01 CA12 4D038 AA08 AB25 AB40 AB87 BA04 BB02 BB18 BB20

Claims (18)

[Claims] 1. A leachate generated at a landfill site for waste such as a residue from a waste incinerator and / or ash melting furnace is introduced into a reverse osmosis membrane filtration device and filtered. Discharge the permeated water, introduce the concentrated water of the reverse osmosis membrane filtration device into the NF filtration device, filter, and return the concentrated water of the NF filtration device to the waste incinerator and / or ash melting furnace to remove harmful water in the concentrated water. A landfill for waste, characterized in that the substance is thermally decomposed and, on the other hand, the permeated water of the NF filtration device is subjected to chelate adsorption treatment, then heated to crystallize the NaCl salt, and then cooled to crystallize the KCl salt. Ground leachate treatment method. 2. Leachate generated at a landfill site for waste such as residue from a waste incinerator and / or ash melting furnace is introduced into a reverse osmosis membrane filtration device and filtered. The permeated water is discharged, the concentrated water of the reverse osmosis membrane filtration device is introduced into the NF filtration device and filtered, and the concentrated water of the NF filtration device is supplied to a pyrolysis furnace to thermally decompose harmful substances in the concentrated water. , After the permeated water of the NF filtration device is subjected to the chelate adsorption treatment,
A method for treating leachate from a landfill for waste disposal, characterized by crystallizing an aCl salt and then cooling to crystallize a KCl salt. 3. Leachate generated at a landfill site for waste such as residue from a waste incinerator and / or ash melting furnace is introduced into a reverse osmosis membrane filtration device and filtered. The permeated water is discharged, the concentrated water of the reverse osmosis membrane filtration device is introduced into the electrodeposition device for electrodeposition, and the concentrated water of the electrodeposition device is returned to the waste incinerator or / and the ash melting furnace to return the concentrated water. Is thermally decomposed, and the permeated water of the electrodeposition apparatus is subjected to chelate adsorption treatment, then heated to crystallize NaCl salts, and then cooled to obtain K
A method for treating leachate from a landfill waste, comprising crystallizing a Cl salt. 4. Leachate generated at a landfill site for waste such as residue from a waste incinerator and / or ash melting furnace is introduced into a reverse osmosis membrane filtration device and filtered. The permeated water is discharged, the concentrated water of the reverse osmosis membrane filtration device is introduced into the promoted oxidation treatment device to decompose harmful substances, and the treated water of the promoted oxidation treatment device is subjected to chelate adsorption treatment and then heated to NaC
1. A method for treating leachate from a landfill for waste disposal, wherein the salt is crystallized and then cooled to crystallize the KCl salt. 5. A leachate generated at a landfill site for waste such as a residue of a waste incinerator or / and ash melting furnace is introduced into a reverse osmosis membrane filtration device and filtered. The permeated water is discharged, the concentrated water of the reverse osmosis membrane filtration device is subjected to chelate adsorption treatment, and then the NaCl salt is crystallized by heating, then cooled to crystallize the KCl salt, and the crystallized NaCl salt is thermally decomposed Injecting into a furnace to thermally decompose harmful substances, and introducing the crystallized KCl salt into a pyrolysis furnace separately from the NaCl salt to thermally decompose harmful substances. Water treatment method. 6. The method according to claim 1, wherein the wastewater after cooling and crystallizing the KCl salt is circulated to the step of crystallizing the NaCl salt. 7. The waste landfill according to claim 1, wherein a part of the waste water after cooling and crystallizing the KCl salt is circulated to the NaCl salt crystallization step, and the remainder is dried. Treatment method for leachate at disposal site. 8. The method according to claim 1, wherein the wastewater after cooling and crystallization of the KCl salt is dried. 9. The waste according to claim 1, wherein a part of the waste water after cooling to crystallize the KCl salt is circulated to the NaCl salt crystallization step, and the remainder is thermally decomposed. Treatment method for leachate at landfill site. 10. A reverse osmosis membrane filtration device for filtering leachate generated at a landfill site for waste such as a residue from a waste incinerator or / and ash melting furnace, and a concentration of the reverse osmosis membrane filtration device. An NF filtration device for filtering water, a chelate adsorption tower for performing chelate adsorption treatment on permeated water of the NF filtration device, and for supplying concentrated water of the NF filtration device to a waste incinerator or / and an ash melting furnace Condensed water return line, Heated crystallizer for heating the treated water from the chelate adsorption tower to crystallize NaCl salt, KCl salt is crystallized by cooling the treated water of the heated crystallizer And a cooling-type crystallization device for causing the leaching water to be discharged from a landfill. 11. A reverse osmosis membrane filtration device for filtering leachate generated at a landfill site for waste such as a residue of a waste incinerator and / or ash melting furnace, and a concentration of the reverse osmosis membrane filtration device. An NF filtration device for filtering water, a chelate adsorption tower for performing chelate adsorption treatment on permeated water of the NF filtration device, and a pyrolysis furnace for introducing concentrated water of the NF filtration device and thermally decomposing harmful substances. A heating type crystallizer for heating the treated water from the chelate adsorption tower to crystallize NaCl salt, and a cooling type crystallizing for cooling the treated water of the heating type crystallizer to crystallize the KCl salt. A treatment device for leachate from a landfill site for waste. 12. A reverse osmosis membrane filtration device for filtering leachate generated at a landfill site for waste such as a residue of a waste incinerator or / and ash melting furnace, and a concentration of the reverse osmosis membrane filtration device. Electrodeposition equipment for electrodeposition treatment of water, Chelate adsorption tower for chelate adsorption treatment of permeated water of electrodeposition equipment, Supply of concentrated water of electrodeposition equipment to waste incinerator or / and ash melting furnace Condensed water return line for heating, a heated crystallizer for heating the treated water from the chelate adsorption tower to crystallize the NaCl salt, and cooling the treated water of the heated crystallizer to remove the KCl salt A treatment device for leachate from a landfill for waste disposal, comprising: a cooling type crystallization device for crystallization. 13. A reverse osmosis membrane filtration device for filtering leachate generated at a landfill site for waste such as a residue of a waste incinerator or / and ash melting furnace, and a concentration of the reverse osmosis membrane filtration device. A promoted oxidation treatment apparatus for decomposing harmful substances by introducing water, a chelate adsorption tower for performing chelate adsorption treatment of the treated water of the promoted oxidation treatment apparatus, and heating the treated water from the chelate adsorption tower with NaCl Disposal, comprising: a heating type crystallizer for crystallizing a salt; and a cooling type crystallizer for crystallizing a KCl salt by cooling treated water of the heating type crystallizer. Treatment equipment for leachate from landfill sites. 14. A reverse osmosis membrane filtration device for filtering leachate generated at a landfill site for waste such as a residue of a waste incinerator and / or ash melting furnace, and a concentration of the reverse osmosis membrane filtration device. A chelate adsorption tower for performing chelate adsorption treatment on water, a heated crystallizer for heating the treated water from the chelate adsorption tower to crystallize NaCl salts, and cooling the treated water of the heated crystallizer -Type crystallizer for crystallizing KCl salt by heating, pyrolysis furnace for introducing NaCl salt from heating-type crystallizer to thermally decompose harmful substances, and KCl from cooling-type crystallizer An apparatus for treating leachate from a landfill for waste disposal, comprising: another pyrolysis furnace for thermally decomposing harmful substances by introducing salt. 15. A drain outlet of a cooling type crystallizer and a chelate adsorption treated water conduit on an inlet side of the heating type crystallizer so that waste water from the cooling type crystallizer can be circulated to the heating type crystallizer. The apparatus for treating leachate from a landfill site according to any one of claims 10 to 14, which is connected by a drainage return conduit. 16. The chelate-adsorbed water at the drain outlet of the cooling type crystallizer and the inlet side of the heating type crystallizer so that a part of the waste water from the cooling type crystallizer can be circulated to the heating type crystallizer. The leachate according to any one of claims 10 to 14, wherein a dryer is provided downstream of the cooling crystallization device so that the conduit and the conduit are connected by a wastewater return conduit, and the remainder of the wastewater can be dried. Processing equipment. 17. The leachate according to claim 10, wherein a drier is provided downstream of the cooling type crystallizer so that the wastewater from the cooling type crystallizer can be dried. Processing equipment. 18. A chelate adsorption treated water at a drain outlet of a cooling type crystallizer and an inlet side of a heating type crystallizer so that a part of the waste water from the cooling type crystallizer can be circulated to the heating type crystallizer. 2. A drainage pipe connected to a pyrolysis furnace so that the drainage pipe is connected to the pipe by a drainage return pipe, and the remainder of the drainage can be pyrolyzed.
An apparatus for treating leachate from a waste landfill according to any one of 0 to 14.