JP2015144997A - Method for treating wastewater containing sulfate ions and boron, and equipment for treating the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide, when treating wastewater containing sulfate ions and boron, a treatment method capable of increasing a rate of adsorption of boron on a laminar double hydroxide.SOLUTION: The treatment method comprises: a first step of passing raw water (wastewater) containing sulfate ions and boron through a reverse osmosis membrane (RO membrane) module of a reverse osmosis membrane device and thereby having sulfate ions removed from raw water (wastewater) containing sulfate ions and boron; and, thereafter, a second step of supplying permeated water (wastewater) having sulfate ions removed and containing boron to an LDH adsorption tower 2, thereby contacting the permeated water and laminar double hydroxide, and having boron in the permeated water adsorbed by the laminae double hydroxide and thereby removed.

Description

  The present invention relates to a technique for removing boron from wastewater containing sulfate ions and boron.

  Desulfurization effluents generated at coal-fired power plants, ceramics plants, etc. contain a large amount of boron together with sulfate ions.

  Here, as a method of removing boron from boron-containing wastewater, for example, there is a method described in Patent Document 1. In the method described in Patent Document 1, first, boron-containing water is concentrated by an evaporation concentration method or the like to obtain boron-concentrated water. Thereafter, the boron-enriched water is brought into contact with the layered inorganic hydroxide, and boron in the boron-enriched water is adsorbed and removed by the layered inorganic hydroxide.

  In Patent Document 1, when boron is removed by concentrating boron-containing water and then contacting with the layered inorganic hydroxide to remove boron, the boron-containing water is contacted with the layered inorganic hydroxide without concentrating the boron-containing water. It is described that the boron removal rate is improved more than that (paragraph 0079 of the specification of Patent Document 1).

Japanese Patent No. 5214756

  However, it is problematic to apply the method described in Patent Document 1 to, for example, desulfurization wastewater (drainage containing not only boron but also sulfate ions) generated in a coal-fired power plant or the like. When waste water containing sulfate ions and boron is brought into contact with the layered inorganic hydroxide, sulfate ions are preferentially adsorbed on the layered inorganic hydroxide over boron. Therefore, in wastewater containing sulfate ions and boron, the amount of boron adsorbed on the layered inorganic hydroxide is extremely reduced.

  In Patent Document 1, boron-containing water is concentrated to form boron-enriched water, and this boron-enriched water is brought into contact with the layered inorganic hydroxide. In this case, when the boron-containing water contains sulfate ions, not only boron but also sulfate ions are concentrated by the concentration operation of the boron-containing water. When this concentrated water is brought into contact with the layered inorganic hydroxide, sulfate ions are preferentially adsorbed to the layered inorganic hydroxide over boron, so that the amount of boron adsorbed extremely decreases. As a result, a large amount of layered inorganic hydroxide is required even though layered inorganic hydroxide is inexpensive. Further, if the amount of the layered inorganic hydroxide is small, treated water (drainage) having a desired boron concentration cannot be obtained.

  The layered inorganic hydroxide is also referred to as layered double hydroxides (Layered Double Hydroxides).

  The present invention has been made in view of the above circumstances, and its purpose is to improve the adsorption rate of boron to the layered double hydroxide when treating wastewater containing sulfate ions and boron. Is to provide a method.

  The present invention is a method for treating waste water containing sulfate ions and boron. In this treatment method, the first step of removing sulfate ions from the waste water, the waste water from which sulfate ions have been removed are brought into contact with the layered double hydroxide, and boron in the waste water is adsorbed on the layered double hydroxide. And removing the second step.

  The present invention also relates to a wastewater treatment facility containing sulfate ions and boron. This treatment equipment is arranged on the downstream side of the sulfate ion removing device for removing sulfate ions from the waste water, and the waste water from which the sulfate ions have been removed is brought into contact with the layered double hydroxide, And an LDH adsorption tower that removes boron in the wastewater by adsorbing the layered double hydroxide to the layered double hydroxide.

  According to the present invention, when treating wastewater containing sulfate ions and boron, the adsorption rate of boron to the layered double hydroxide can be remarkably increased as compared with a known boron-containing wastewater treatment technique.

It is a block diagram which shows the waste water treatment facility which concerns on 1st Embodiment of this invention. It is a block diagram which shows the waste water treatment facility which concerns on 2nd Embodiment of this invention. It is a block diagram which shows the waste water treatment facility which concerns on 3rd Embodiment of this invention. It is a graph which shows the relationship between the sulfate ion density | concentration in the to-be-processed water (raw water) containing a sulfate ion and a boron at the time of using a layered double hydroxide as an adsorbent, and a boron adsorption amount. It is a graph which shows the relationship between the boron density | concentration in the to-be-processed water (raw water) containing a sulfate ion and a boron at the time of using a layered double hydroxide as an adsorbent, and a boron adsorption amount.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. In the following description, in describing the configuration of the wastewater treatment facility according to the embodiment of the present invention, each step in the method for treating wastewater containing sulfate ions and boron will be described.
Here, boron refers to boron ions dissolved in water, and exists in the form of borate ions or hydroxide ions, for example.

(Configuration of wastewater treatment facility of the first embodiment)
As shown in FIG. 1, the wastewater treatment facility 100 of the first embodiment includes a reverse osmosis membrane device 1 and an LDH adsorption tower 2 in order from the upstream side of the treatment process. In addition, the density | concentration of the sulfate ion in raw | natural water (drainage) is 2000 mg / L, for example, and the density | concentration of boron is 200-500 mg / L, for example. Further, SOx is contained in exhaust gas generated at a coal-fired power plant or the like. When this exhaust gas is washed with water, SOx dissolves in the water as sulfate ions.

<Reverse osmosis membrane device (sulfate ion removal device)>
The reverse osmosis membrane device 1 is a device comprising a reverse osmosis membrane module in which an RO membrane (reverse osmosis membrane) is incorporated, a pump for supplying raw water (drainage) to the reverse osmosis membrane module, and the like.

  By passing raw water (drainage) containing sulfate ions and boron through the reverse osmosis membrane module (RO membrane) of the reverse osmosis membrane device 1, sulfate ions are removed from the raw water (drainage) containing sulfate ions and boron (first) 1 step). When the raw water is passed through the reverse osmosis membrane module of the reverse osmosis membrane device 1 via the pipe 11, sulfate ions in the raw water are blocked by the RO membrane and flow through the pipe 13 as concentrated water containing sulfate ions. On the other hand, since boron in raw water is easier to permeate the RO membrane than sulfate ions, it flows through the pipe 12 as permeated water containing boron.

  Note that sulfate ions may be removed from wastewater containing sulfate ions and boron by using NF membranes (nanofiltration membranes) instead of RO membranes (by NF membranes). Furthermore, instead of membrane separation methods such as RO membranes and NF membranes, sulfuric acid is removed from wastewater containing sulfate ions and boron by coagulation sedimentation treatment (coagulation sedimentation method), electrodialysis, evaporation concentration treatment (evaporation concentration method), etc. Ions may be removed.

  Moreover, it is although it does not specifically limit as pH at the time of a process (1st process and the 2nd process mentioned later), It can process by pH 5-pH11. From the viewpoint of removing boron ions, neutral to weak alkaline is preferable, and the treatment is performed at pH 7 to 9.5 and further pH 8 to 9. On the other hand, when a membrane such as a reverse osmosis membrane is used (first step), the scale can be suppressed by adjusting the pH to about 5 to 7. When the pH is adjusted to 5 to 7, the pH can be adjusted to neutral to weakly alkaline (for example, pH 7 to 9.5, further pH 8 to 9) before the treatment in the LDH adsorption tower (second step) described later. preferable.

  Although it is not necessary to completely remove sulfate ions from the wastewater, it is preferable to remove sulfate ions from the wastewater by the reverse osmosis membrane device 1 so that the concentration of sulfate ions is 1000 mg / L or less. This is because the boron adsorption amount to LDH can be increased by setting the sulfate ion concentration in the water to be treated to 1000 mg / L or less.

<LDH adsorption tower>
The LDH adsorption tower 2 disposed on the downstream side of the reverse osmosis membrane device 1 is an adsorption tower in which a layered double hydroxide (LDH) is filled. Note that layered double hydroxide (abbreviation LDH) is a layered compound having an anion exchange ability and an inorganic skeleton (metal hydroxide layer), and is represented by the following general formula.
^{_{[M 2+ 1-x M 3+}} x (OH) 2] [A n- x / n · mH 2 O]

  By supplying permeated water (drainage) containing boron ions from which sulfate ions have been removed by the reverse osmosis membrane device 1 to the LDH adsorption tower 2, the permeated water and the layered double hydroxide are brought into contact with each other. Boron is removed by adsorbing to the layered double hydroxide (second step). The permeated water (drainage) from which boron has been removed flows through the pipe 14 as treated water.

  Here, FIG. 4 is a graph showing the relationship between the sulfate ion concentration in the treated water (raw water) containing sulfate ions and boron and the boron adsorption amount when the layered double hydroxide is used as the adsorbent. It is. FIG. 5 is a graph showing the relationship between the boron concentration in the water to be treated (raw water) containing sulfate ions and boron and the boron adsorption amount when layered double hydroxide is used as the adsorbent.

  First, as shown in FIG. 5, regarding the boron concentration in the water to be treated containing sulfate ions and boron, it can be seen that the amount of boron adsorbed on LDH increases in proportion to the increase in the boron concentration in the water to be treated. . On the other hand, regarding the sulfate ion concentration in the treated water containing sulfate ions and boron, when the sulfate ion concentration in the treated water is as high as 2000 mg / L, compared to the case where the sulfate ion concentration is 1000 mg / L or less. It can be seen that the amount of boron adsorbed on LDH is extremely reduced.

(Action / Effect)
According to the wastewater treatment facility 100 of the present embodiment, the layered double hydroxide is brought into contact with the layered double hydroxide by contacting the wastewater from which sulfate ions preferentially adsorbed on the layered inorganic hydroxide with boron are contacted with the layered double hydroxide. Since boron is adsorbed and removed, the adsorption rate of boron to the layered double hydroxide can be increased. Therefore, the adsorption amount of boron can be increased as compared with the processing method described in Patent Document 1.

  Here, as a method for removing sulfate ions, it is preferable to use an RO membrane (reverse osmosis membrane) or an NF membrane (nanofiltration membrane) as in this embodiment. Sulfate ions can also be removed from waste water containing sulfate ions and boron by methods such as coagulation precipitation treatment (coagulation precipitation method), electrodialysis, and evaporation concentration treatment (evaporation concentration method). According to the (aggregation precipitation method), a large amount of drug to be injected is required, which is disadvantageous in terms of processing costs. In addition, according to electrodialysis and evaporative concentration treatment (evaporation concentration method), the amount of electric power required is large, which is similarly disadvantageous in terms of processing costs. Treatment using an RO membrane (reverse osmosis membrane) or NF membrane (nanofiltration membrane), which does not require chemical injection and requires only a relatively small amount of electric power, can reduce the treatment cost.

In this embodiment, raw water containing 2000 mg / L of sulfate ions is used, but the concentration of sulfate ions in the raw water is not limited to this. By applying this treatment method to raw water containing 1500 mg / L or more of sulfate ions, the effect of increasing the amount of boron adsorbed is greatly exhibited. In addition, this process method can be applied more suitably about the raw | natural water containing 2000 mg / L or more which is a saturated state.
Further, the LDH referred to in the present application includes nano-layered condensed hydroxide.

(Configuration of wastewater treatment facility of the second embodiment)
The waste water treatment facility 101 of the second embodiment will be described with reference to FIG. In addition, in the waste water treatment facility 101 shown in FIG. 2, the same code | symbol is attached | subjected about the apparatus and piping similar to the equipment and piping which comprise the waste water treatment facility 100 shown in FIG.

  Boron is contained in the concentrated water flowing through the pipe 15 separated by the reverse osmosis membrane device 1 (the concentrated water of sulfate ions removed in the first step). This is because boron is easier to permeate the RO membrane than sulfate ions, but some flows out to the pipe 15 without permeating the RO membrane. The wastewater treatment facility 101 according to the second embodiment intends to adsorb and remove boron that has flowed into the pipe 15 without passing through the RO membrane with the layered double hydroxide.

  A sulfate ion removal tank 3 and a second LDH adsorption tower 4 are installed on the concentrated water side of the reverse osmosis membrane device 1 in order from the upstream side of the treatment process. The reverse osmosis membrane device 1 and the sulfate ion removal tank 3 are connected by a pipe 15, and the sulfate ion removal tank 3 and the second LDH adsorption tower 4 are connected by a pipe 16. A pipe 14 on the downstream side of the LDH adsorption tower 2 on the permeate water side and a pipe 16 connecting the sulfate ion removal tank 3 on the concentrated water side and the second LDH adsorption tower 4 are connected by a pipe 18.

<Sulfate ion removal tank>
The sulfate ion removal tank 3 is a coagulation sedimentation tank comprising a tank body and a device for injecting a flocculant (chemical) such as PAC (polyaluminum chloride) into the tank body.

<Second LDH adsorption tower>
The second LDH adsorption tower 4 arranged on the downstream side of the sulfate ion removal tank 3 is an adsorption tower in which a layered double hydroxide (LDH) is filled inside, like the LDH adsorption tower 2 on the permeate side.

  In this embodiment, the concentrated water of sulfate ions removed by the reverse osmosis membrane device 1 (first step) is introduced into the sulfate ion removal tank 3 and PAC (flocculating agent) is injected into the sulfate ion removal tank 3. Thus, the sulfate ions in the concentrated water are aggregated as calcium sulfate (sulfate). Then, the agglomerated calcium sulfate is pulled out from the tank bottom and removed. In addition, the calcium source of calcium sulfate is calcium originally contained in the concentrated water.

  Thereafter, the concentrated water containing boron from which sulfate ions have been removed is supplied to the second LDH adsorption tower 4 via the pipe 16 so that the concentrated water and the layered double hydroxide are brought into contact with each other. It is removed by adsorbing to the layered double hydroxide (sulfate ion concentrated water treatment step). The concentrated water (drainage) from which boron has been removed flows through the pipe 17 as treated water.

  Here, in this embodiment, a part of the permeated water that has exited the permeated water side LDH adsorption tower 2 and from which boron has been removed is sent to the pipe 16 via the pipe 18, and the concentrated water that has exited the sulfate ion removal tank 3 is supplied. It is diluted. Thereafter, boron is adsorbed and removed by the second LDH adsorption tower 4. That is, in the sulfate ion concentrated water treatment step, the concentrated water from which sulfate ions have been removed in the sulfate ion removal tank 3 is diluted with the treated water obtained in the second step, and then the second LDH adsorption tower 4 is used to form a layered composite. In contact with the hydroxide, boron in the concentrated water is removed by adsorbing the layered double hydroxide.

(Action / Effect)
In this embodiment, by injecting PAC (flocculating agent) into the concentrated sulfate ion water removed in the reverse osmosis membrane device 1 (first step), the sulfate ions in the concentrated water are aggregated and removed as sulfate. Then, it is brought into contact with the layered double hydroxide and removed by adsorbing boron in the concentrated water from which sulfate ions have been removed to the layered double hydroxide. According to this configuration, boron that has flowed to the concentrated water side without passing through a membrane such as the RO membrane can also be adsorbed and removed by the layered double hydroxide with an increased adsorption rate.

In addition, not PAC (flocculating agent) but a chemical such as slaked lime (Ca (OH) ₂ ) is injected into the sulfate ion removal tank 3 to precipitate and remove sulfate ions in the concentrated water as calcium sulfate (sulfate). Then, it may be removed by contacting with the layered double hydroxide and adsorbing boron in the concentrated water from which sulfate ions have been removed to the layered double hydroxide.

  In the present embodiment, the concentrated water from which sulfate ions have been removed in the sulfate ion removal tank 3 is diluted with treated water obtained in the LDH adsorption tower 2 on the permeate side, and then the second LDH adsorption tower 4 is used. In contact with the layered double hydroxide, boron in the concentrated water is removed by adsorbing the layered double hydroxide to the layered double hydroxide. According to this configuration, since the concentrated water supplied to the second LDH adsorption tower 4 is diluted with the treated water, even if the concentrated water exiting the sulfate ion removal tank 3 contains 2000 mg / L or more of sulfate ions, Since the sulfate ion concentration is lowered by being diluted before entering the second LDH adsorption tower 4 (for example, the sulfate ion concentration in the concentrated water is lowered so that the sulfate ion concentration is 1000 mg / L or less), the second LDH adsorption is performed. In the tower 4, it is possible to prevent boron adsorption from being inhibited by sulfate ions (the same applies to the third embodiment).

(Configuration of wastewater treatment facility of the third embodiment)
The waste water treatment facility 102 of the third embodiment will be described with reference to FIG. In addition, in the waste water treatment facility 102 shown in FIG. 3, the same code | symbol is attached | subjected about the apparatus and piping similar to the device and piping which comprise the waste water treatment facility 101 shown in FIG.

<Sulfate ion removal tank>
The main difference between the second embodiment and the third embodiment is the sulfate ion removal tank. The sulfate ion removal tank 3 of the second embodiment includes a device for injecting an aggregating agent (drug) such as PAC (polyaluminum chloride), but the sulfate ion removal tank 5 of the present embodiment is an injection of a drug. Does not have any equipment. The sulfate ion concentrated water treatment process of this embodiment is a process by a crystallization method, and is a process that does not particularly require a chemical. The sulfate ion removal tank 5 is a tank for removing sulfate ions in concentrated sulfate ion water by a crystallization method.

<Return piping>
The pipe 19 for returning a part of the concentrated sulfate ion water removed in the reverse osmosis membrane device 1 (first step) to the upstream side of the reverse osmosis membrane device 1 (first step) is drained in the present embodiment. The processing facility 102 has. The pipe 19 branches from a pipe 15 that connects the reverse osmosis membrane device 1 and the sulfate ion removal tank 3, and a downstream end is connected to a pipe 11 that supplies raw water to the reverse osmosis membrane device 1.

  In this embodiment, the concentrated water of sulfate ions removed by the reverse osmosis membrane device 1 (first step) is put into the sulfate ion removal tank 5, and the sulfate ions in the concentrated water are crystallized as calcium sulfate (sulfate). Analyze. Then, the crystallized calcium sulfate is pulled out from the tank bottom and removed. The calcium source of calcium sulfate is, for example, calcium originally contained in the concentrated water. Further, the concentrated water flowing through the pipe 15 is in a state in which sulfate ions are supersaturated by the concentration operation in the reverse osmosis membrane device 1. The supersaturated state means a state in which sulfate ions are not less than the saturated value but not precipitated.

  Thereafter, the concentrated water containing boron from which sulfate ions have been removed is supplied to the second LDH adsorption tower 4 via the pipe 16 so that the concentrated water and the layered double hydroxide are brought into contact with each other. It is removed by adsorbing to the layered double hydroxide (sulfate ion concentrated water treatment step). The concentrated water (drainage) from which boron has been removed flows through the pipe 17 as treated water.

  Here, in the present embodiment, a portion of the concentrated sulfate ion water removed in the reverse osmosis membrane device 1 (first step) is sent to the sulfate ion removal tank 5 (sulfate ion concentrated water treatment step) and the rest. Is returned to the upstream side of the reverse osmosis membrane device 1 (first step). The ratio of the amount of concentrated water sent to the sulfate ion removal tank 3 and the amount of concentrated water returned to the upstream side of the reverse osmosis membrane device 1 is, for example, 1:10.

(Action / Effect)
In the present embodiment, sulfate ions in the concentrated water of sulfate ions removed in the reverse osmosis membrane device 1 (first step) are removed by crystallization, and then contacted with the layered double hydroxide to produce sulfate ions. Is removed by adsorbing boron in the concentrated water from which water is removed to the layered double hydroxide. According to this configuration, since a chemical such as a flocculant is not used, the processing cost can be reduced. In addition, the amount of precipitate (solid waste) generated is small because no flocculant is added. Also from this viewpoint, the processing cost can be reduced.

  Moreover, in this embodiment, while sending a part of sulfate ion concentrated water removed in the reverse osmosis membrane device 1 (first step) to the sulfate ion removal tank 5 (sulfate ion concentrated water treatment step), the rest The reverse osmosis membrane device 1 (first step) is returned to the upstream side. Here, when all of the concentrated sulfate ion water removed in the reverse osmosis membrane device 1 (first step) is sent to the sulfate ion removal tank 5 for crystallization treatment, from the material balance, from the reverse osmosis membrane device 1 It is necessary to send concentrated water having a much larger amount of water than the amount of water sent to the LDH adsorption tower 2 to the sulfate ion removal tank 5. As described above, a portion of the concentrated sulfate ion water removed in the reverse osmosis membrane device 1 is sent to the sulfate ion removal tank 5, and the rest is sent upstream of the reverse osmosis membrane device 1 (first step). If it returns, the difference between the amount of water sent from the reverse osmosis membrane device 1 to the LDH adsorption tower 2 and the amount of water sent from the reverse osmosis membrane device 1 to the sulfate ion removal tank 5 can be reduced. As a result, the concentrated water sent from the sulfate ion removal tank 5 to the second LDH adsorption tower 4 can be sufficiently diluted with the treated water obtained in the LDH adsorption tower 2 on the permeate side.

1: Reverse osmosis membrane device (sulfuric acid ion removal device)
2: belt type concentrator 3, 5: sulfate ion removal tank 4: second LDH adsorption towers 11-19: piping 100, 101, 102: waste water treatment equipment

Claims (10)

A method for treating wastewater containing sulfate ions and boron,
A first step of removing sulfate ions from the waste water;
A second step of removing the waste water from which sulfate ions have been removed by bringing the waste water into contact with the layered double hydroxide and adsorbing boron in the waste water to the layered double hydroxide;
A wastewater treatment method comprising: The waste water treatment method according to claim 1,
The first process is a process for removing sulfate ions from the waste water using a reverse osmosis membrane or a nanofiltration membrane. In the wastewater treatment method according to claim 1 or 2,
By injecting the drug into the concentrated water of sulfate ions removed in the first step, the sulfate ions in the concentrated water are removed by precipitation or aggregation as sulfate, and then contacted with the layered double hydroxide. The wastewater treatment method further comprises a sulfate ion concentrated water treatment step for removing boron in the concentrated water from which sulfate ions have been removed by adsorbing the boron to the layered double hydroxide. In the wastewater treatment method according to claim 1 or 2,
The sulfate ions in the concentrated water of the sulfate ions removed in the first step are removed by crystallization, and then brought into contact with the layered double hydroxide, so that the boron in the concentrated water from which the sulfate ions have been removed is layered. A wastewater treatment method, further comprising a sulfate ion concentrated water treatment step of removing by adsorption to a hydroxide. The waste water treatment method according to claim 4,
A part of the sulfate ion concentrated water removed in the first step is sent to the sulfate ion concentrated water treatment step, and the rest is returned to the upstream side of the first step. . In the wastewater treatment method according to any one of claims 3 to 5,
In the sulfate ion concentrated water treatment step, the concentrated water from which sulfate ions have been removed is diluted with the treated water obtained in the second step, and then brought into contact with the layered double hydroxide to form boron in the concentrated water. The wastewater treatment method is characterized in that it is removed by adsorbing to the layered double hydroxide. A wastewater treatment facility containing sulfate ions and boron,
A sulfate ion removal device for removing sulfate ions from the waste water;
LDH which is disposed downstream of the sulfate ion removing device and removes the waste water from which sulfate ions have been removed by contacting with the layered double hydroxide and adsorbing boron in the waste water to the layered double hydroxide. An adsorption tower,
A wastewater treatment facility characterized by comprising: In the waste water treatment facility according to claim 7,
The said sulfate ion removal apparatus is equipped with a reverse osmosis membrane or a nanofiltration membrane, The sulfate ion is removed from the said wastewater with the said reverse osmosis membrane or a nanofiltration membrane, The wastewater treatment equipment characterized by the above-mentioned. The waste water treatment facility according to claim 7 or 8,
A sulfate ion removal tank that removes sulfate ions in the concentrated water by precipitating or aggregating them as sulfates by injecting a chemical into the concentrated water of sulfate ions removed in the sulfate ion removing device;
The concentrated water from which the sulfate ions have been removed is brought into contact with the layered double hydroxide and is removed by adsorbing boron in the concentrated water to the layered double hydroxide. A 2LDH adsorption tower;
A wastewater treatment facility, further comprising: The waste water treatment facility according to claim 7 or 8,
A sulfate ion removal tank for removing sulfate ions in the concentrated water of sulfate ions removed in the sulfate ion removal device by a crystallization method;
The concentrated water from which the sulfate ions have been removed is brought into contact with the layered double hydroxide and is removed by adsorbing boron in the concentrated water to the layered double hydroxide. A 2LDH adsorption tower;
A wastewater treatment facility, further comprising:

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