JP3581726B2 - Waste liquid treatment method and waste liquid treatment device - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a waste liquid treatment method and a waste liquid treatment apparatus. The present invention relates to a waste liquid treatment method that does not require a cooling device for removing or a stirring power required for rapid waste liquid treatment, and a waste liquid treatment device that performs the method.
[0002]
[Prior Art and Problems to be Solved by the Invention]
At present, wastewater discharged from factories cannot be directly discharged into rivers from the viewpoint of protecting the natural environment or preventing pollution. At least when the waste liquid is acidic or alkaline, it is necessary to discharge the waste liquid after neutralizing the waste liquid. The waste liquid generated by various analysis operations or measurement operations in factories or the like must be discharged after neutralization as in the case of the waste liquid.
[0003]
The waste liquid treatment is not limited to the neutralization treatment as described above. Some waste liquids contain dissolved or colloidal substances, and the substances do not precipitate as they are. Such waste liquid is converted into a sedimentable substance by adding a coagulant, and the waste liquid is discharged after performing a precipitation treatment in a settling tank or the like.
[0004]
In the conventional waste liquid treatment, a neutralizing agent, a coagulant or another waste liquid treatment agent is supplied in a predetermined amount into a waste liquid tank containing the waste liquid, and the waste liquid in the waste liquid tank is stirred, thereby performing the waste liquid treatment. I was
[0005]
In such waste liquid treatment, a constant-rate pump for supplying a constant amount of the waste liquid treating agent into the waste liquid tank and a power source for driving the pump are required, and a stirring for stirring the waste liquid in the waste liquid tank is required. A drive for driving the device and its stirring device is required. Thus, the conventional waste liquid treatment method requires a power source, which consumes a large amount of power, and the waste liquid treatment requires a great deal of cost. Since various devices such as a supply device and a stirring device must be provided, there is a problem that the device or the processing system is inevitably enlarged.
[0006]
The present invention has been completed based on the above circumstances. SUMMARY OF THE INVENTION An object of the present invention is to eliminate the necessity of a forced liquid sending device for supplying a waste liquid treating agent, a driving source for driving the same, and a power device such as a stirring device. An object of the present invention is to provide a waste liquid treatment device having a simple device configuration because no device is required.
[0007]
[Means for Solving the Problems]
A waste liquid treatment method and a waste liquid treatment apparatus according to the present invention for solving the above-described problems are based on the principle that the treatment liquid is leached into the waste liquid through a porous member and the waste liquid is treated with the treatment liquid.
[0008]
According to the principle of the present invention, the treatment liquid is not directly introduced into the waste liquid, but the treatment liquid that has oozed from the porous member and the waste liquid are brought into contact. The amount of the treatment liquid that seeps into the waste liquid side through the porous member is determined according to the immersion surface area of the porous member that comes into contact with the waste liquid .
[0009]
Based on such a principle, the means of the present invention is proposed as follows.
[0010]
That is, the means according to claim 1 can store the processing liquid in the waste liquid stored in the waste liquid tank such that the liquid level is kept constant, and combine the processing liquid and the waste liquid with the porous member. The treatment liquid that is generated by immersing the treatment liquid supply tank that is isolated by the treatment liquid and adjusting the amount of the treatment liquid so that the liquid level of the treatment liquid existing in the treatment liquid supply tank is higher than the liquid level of the waste liquid. Leaching from the waste liquid side surface of the porous member according to the gravity of the porous member, and treating the waste liquid with a treatment liquid having a seepage amount determined according to the magnitude of the immersion surface area of the porous member in contact with the waste liquid. Wastewater treatment method,
The invention according to claim 2 is the waste liquid treatment method according to claim 1, wherein the porous member is attached to a treatment liquid supply tank such that an immersion surface area in contact with the waste liquid is variable.
According to a third aspect of the present invention, there is provided a waste liquid tank for storing a waste liquid so that the liquid level is maintained at a constant level, and a treatment liquid having a liquid level higher than the liquid level of the waste liquid in the waste liquid tank. A waste liquid processing apparatus comprising: a processing liquid supply tank that can be accommodated and is immersed in a waste liquid in the waste liquid tank so that the processing liquid and the waste liquid are separated by a porous member.
[0011]
[Action]
In the present invention, the treatment liquid and the waste liquid are not in direct contact with each other in the sense that the treatment liquid is not directly introduced into the waste liquid. In the present invention, the treatment liquid and the waste liquid are separated by the porous member. Then, the processing liquid passes through the porous member, and the processing liquid exudes from the porous member to the waste liquid side, so that the processing liquid and the waste liquid come into contact with each other. Therefore, since a large amount of the processing liquid does not directly come into contact with the waste liquid, slow waste liquid processing is performed. Therefore, a cooling device for removing heat generated due to rapid waste liquid treatment is not required.
[0012]
The amount of the treatment liquid that seeps out of the porous member is determined by the immersion surface area of the porous member immersed in the waste liquid. The immersion surface area refers to an area where the solid member comes into contact with the waste liquid when the porous member is assumed to be a solid member.
By adjusting the immersion surface area of the porous member, the amount of the treatment liquid that seeps out of the porous member is adjusted. Therefore, when the waste liquid is, for example, waste acid or waste alkali, the porous member is selected according to the strength of the acid or the concentration of the acid in the waste liquid, or the strength of the alkali or the concentration of the alkali in the waste liquid. This makes it possible to adjust the waste liquid treatment speed. In other words, when the processing agent is supplied into the waste liquid by the pump as in the related art, by controlling the driving amount of the pump to adjust the supply amount, the conventional waste liquid processing method and the conventional waste liquid processing apparatus are used. However, in the present invention, such a power source is not required, and the supply amount of the processing liquid into the waste liquid can be adjusted only by selecting the porous member. That is, the supply amount of the processing liquid into the waste liquid can be adjusted without a power source.
[0014]
Here, the material of the porous member is not particularly limited as long as it is a member having chemical resistance and is porous so as to allow liquid components to pass therethrough without allowing solid components to pass through. Even if chemical resistance is required, it is only required that it has chemical resistance in the sense that it is not attacked by the waste liquid to be treated and the treating agent. Don't be mistaken as requiring chemical resistance for all chemicals. As a material for forming such a porous member, for example, ceramic (eg, aluminum oxide, zeolite, etc.), carbonaceous material (eg, amorphous carbon, carbon fiber, carbon fiber whisker, etc.), woody material (eg, wood flour, Wood chips, etc.), synthetic resins, and fiber products (woven, knitted, non-woven). Preferably, these materials are appropriately selected according to the types of the waste liquid and the processing liquid, and processed into a porous member according to the selected materials. For example, when aluminum oxide is selected as a ceramic suitable for the neutralization treatment, a porous member is formed by sintering aluminum oxide powder.
[0015]
In addition, the average pore diameter, the pore distribution amount, and the like of the pores in the porous member can be appropriately determined in consideration of the processing liquid passage speed and the like according to the type of the processing liquid.
[0016]
As the waste liquid in the waste liquid treatment method and the waste liquid treatment apparatus according to the present invention, a waste liquid discharged in a semiconductor process, for example, a hydrofluoric acid-containing waste liquid, a waste liquid discharged from a plating plant or the like, for example, a waste liquid after decomposing cyan, a waste liquid from other plants, Waste acid and alkali discharged, various waste liquids discharged from medical sites such as hospitals, waste liquid discharged in the photographic development process, and analyzed and operated at universities, research laboratories, various factories, test sites and other places Waste liquid generated after the analysis. The above classification of the waste liquid mainly focuses on the place where the waste liquid is generated. Classified from another perspective, many waste liquors can be divided into waste acids and waste alkalis. INDUSTRIAL APPLICABILITY The waste liquid treatment method and waste liquid treatment apparatus of the present invention are suitable for neutralizing waste acid or waste alkali.
[0017]
However, the waste liquid treatment method and waste liquid treatment apparatus of the present invention should not be considered to be limited to neutralization treatment of waste acid and waste alkali. The waste liquid treatment method and waste liquid treatment apparatus of the present invention can be applied to waste liquid treatment for aggregating colloidal components in the waste liquid. In short, the waste liquid treatment method and waste liquid treatment apparatus of the present invention can be applied to all waste liquid treatments in which waste liquid can be treated with a treatment agent that can pass through a porous member.
[0018]
The treating agent for treating the waste liquid is appropriately selected according to the content of the waste liquid treatment. When the waste liquid treatment is a neutralization treatment and the waste liquid is a waste acid, the treating agent is an alkaline agent, and examples thereof include caustic soda, caustic potash, sodium carbonate, and ammonia. When the waste liquid is a waste alkali, the treating agent is an acid, and examples thereof include inorganic acids such as hydrochloric acid and sulfuric acid, and organic acids such as acetic acid. These acids and alkali agents are appropriately determined according to the kind of the waste liquid and the concentrations of the acid component and the alkali component.
[0019]
In the present invention, by selecting a treatment agent, treatment such as neutralization treatment, oxidation treatment, reduction treatment, precipitation treatment, and sterilization treatment of the waste liquid is performed.
[0020]
【Example】
A waste liquid treatment method according to one embodiment of the present invention will be described below with reference to the drawings.
[0021]
The waste liquid processing apparatus 1 shown in FIG. 1 has a waste liquid tank 2, a processing liquid storage tank 3, and a processing liquid supply tank 4.
[0022]
In general, the shape and structure of the waste liquid tank are not particularly limited as long as they have a function of storing waste liquid. In this embodiment, the waste liquid tank 2 has a waste liquid supply port 5 for supplying a waste liquid at a lower side surface of the waste liquid tank 2, and a liquid discharge port 6 for discharging a liquid after waste liquid treatment is provided at an upper side surface of the waste liquid tank 2. It is a tank. In the waste liquid tank 2 in this embodiment, the waste liquid is supplied from the waste liquid supply port 5 into the waste liquid tank 2 at a predetermined flow rate, and the waste liquid treated liquid is discharged from the liquid discharge port 6 at a predetermined flow rate. I have. Therefore, it can be said that the waste liquid treatment apparatus 1 in this embodiment is of a flow type.
[0023]
The processing liquid supply tank 4 is attached to a lid provided above the waste liquid tank 2 by a mounting device (not shown) for attaching the processing liquid supply tank 4.
[0024]
Generally speaking, if the processing liquid supply tank 4 has a structure capable of storing the processing liquid and separating the processing liquid and the waste liquid with a porous member, the processing liquid supply tank 4 may be used. There is no particular limitation on the type, shape, structure, etc. In this embodiment, as shown in FIG. 3, a substantially cylindrical tank main body 4a and a liquid-tight mounting by screwing the upper peripheral side surface of the tank main body 4a to close an upper opening of the tank main body 4a are closed. And a ceramic porous member 4c provided at the bottom of the tank body 4a.
[0025]
As shown in FIG. 3, the lid member 4b is further provided with an opening that opens into the processing liquid supply tank 4 at an appropriate position, and a pipe 7 is attached to the opening. The pipe 7 is flexible, and the other end is connected to the processing liquid storage tank 3.
[0026]
When the lid member 4b is liquid-tightly mounted on the upper opening of the tank body 4a, the processing liquid in the processing liquid storage tank 3 fills the processing liquid in the processing liquid supply tank 4 via the pipe 7. be able to. Here, it is significant that the pipe 7 has flexibility. That is, when the pipe 7 has flexibility, the position of the processing liquid storage tank 3 is appropriately adjusted while the processing liquid supply tank 4 and the processing liquid storage tank 3 are connected with the pipe 7. Can be moved up and down. Since the pressure of the processing liquid in the processing liquid supply tank 4 is determined according to the height of the processing liquid storage tank 3, the height position of the processing liquid storage tank 3 is appropriately adjusted to thereby adjust the processing liquid supply tank 4. The pressure of the processing solution inside can be appropriately adjusted. By adjusting the pressure in the processing liquid supply tank 4, it is possible to prevent the waste liquid from reversely osmosis into the processing liquid supply tank 4 through the porous member 4 c, and to prevent the processing liquid from flowing into the waste liquid tank 2. It is possible to adjust the amount of bleeding into the inside.
[0027]
However, the adjustment of the internal pressure of the processing liquid in the processing liquid supply tank 4 is not achieved only by adjusting the vertical position of the processing liquid storage tank 3 connected to the flexible pipe 7, and other appropriate adjustments are made. Needless to say, this can be achieved by the means described above.
[0028]
The porous member 4c is attached to the bottom of the processing liquid supply tank 4. As shown in FIGS. 2 and 3, in this embodiment, four porous members 4c have a substantially cylindrical shape, and four porous members 4c are attached to the bottom surface of the processing liquid supply tank 4 via mounting members 4d. The mounting member 4d is an annular member formed of an elastic member and attached to a mounting hole 4e formed on the bottom surface of the processing liquid supply tank 4. The porous member 4c penetrates through the annular hole of the mounting member 4d, and the elasticity of the mounting member 4d holds the porous member 4c. Since the porous member 4c is held by the elasticity of the mounting member 4d, the porous member 4c is pushed up or down as shown in FIG. The length of the exposed portion of the quality member 4c can be appropriately adjusted.
[0029]
In this embodiment, although the number of the porous members 4c mounted on the bottom surface of the processing liquid supply tank 4 is five, the number of the porous members 4c mounted is not limited. The shapes of the porous members 4c need not always be the same.
[0030]
The porous member 4c having a large diameter and the porous member 4c having a small diameter shown in FIG.
[0031]
In short, the shape and size of the porous member 4c and the number of the porous members 4c mounted on the bottom surface of the processing liquid supply tank 4 according to the scale of processing the waste liquid with the processing liquid or the type of the processing liquid and the type of the waste liquid. Is appropriately determined.
[0032]
The mounting device for attaching the processing liquid supply tank 4 to the lid of the waste liquid tank 2 is provided with the processing liquid supply tank 4 at such a depth that the porous member 4c in the processing liquid supply tank 4 can be sufficiently immersed in the waste liquid. There is no particular restriction on the structure so long as it can be stopped.
[0033]
The processing liquid storage tank 3 is a container or a tank that stores the processing liquid supplied to the processing liquid supply tank 4.
[0034]
As described above, in this embodiment, the processing liquid storage tank 3 is designed so that its vertical position can be changed. Since the configuration of the device for changing the vertical position can be easily deduced by those skilled in the art, a detailed description thereof will be omitted.
[0035]
The operation of the waste liquid treatment apparatus 1 having the above configuration will be described below.
[0036]
A waste liquid is supplied from the waste liquid supply port 5 into the waste liquid tank 2. The supply amount of the waste liquid is appropriately set. In this case, the waste liquid may be either a waste acid or a waste alkali. The supplied waste liquid is discharged from a liquid discharge port 6 in the waste liquid tank 2.
[0037]
About the lower half of the processing liquid supply tank 4 is immersed in the waste liquid in the waste liquid tank 2. Since the porous member 4c projects from the bottom surface of the processing liquid supply tank 4 and is exposed, the exposed porous member 4c is immersed in the waste liquid.
[0038]
The processing liquid stored in the processing liquid storage tank 3 fills the processing liquid supply tank 4 through the pipe 7. The processing liquid in the processing liquid supply tank 4 oozes into the waste liquid from the surface of the porous member 4c immersed in the waste liquid through the porous member 4c.
[0039]
The exuded treatment liquid reacts slowly with the waste liquid to perform the waste liquid treatment. As described above, when the waste liquid is waste acid, the processing liquid is an alkaline liquid, and when the waste liquid is waste alkali, the processing liquid is an acidic liquid.
[0040]
If the waste liquid is, for example, waste acid, the acid concentration in the waste acid generated from the waste liquid generation point is usually almost constant, so it is only necessary to keep the surface area of the porous material immersed in the waste liquid constant. Thus, the amount of the treatment liquid that seeps into the waste liquid from the surface of the porous material can be made constant. When the acid concentration in the waste acid flowing into the waste liquid tank 2 changes and waste acid having a changed constant acid concentration flows into the waste liquid tank 2, the processing liquid supply tank 4 is discharged. As shown in FIG. 5, the porous member 4c exposed from the bottom surface of the processing liquid supply tank 4 pulled up from the tank 2 is further pulled out or pushed in to shorten it, thereby processing the porous member 4c. The surface area exposed from the bottom surface of the liquid supply tank 4 is preferably adjusted to be large or small as appropriate. Then, the processing liquid supply tank 4 having the porous member 4c having the adjusted exposed surface area is attached to the waste liquid tank 2 again, and the porous member 4c is immersed in the waste liquid. Processing can be performed appropriately.
[0041]
Since the amount of the processing liquid that seeps out of the surface of the porous member 4c may be influenced by the relative magnitude of the pressure of the waste liquid in the waste liquid tank 2 and the pressure of the processing liquid in the processing liquid supply tank 4, As shown in FIG. 6, the height H of the processing liquid storage tank 3 may be adjusted.
[0042]
As described above, according to the waste liquid treatment apparatus 1 according to the embodiment of the present invention, by adjusting the surface area of the porous member 4c immersed in the treatment liquid, it is possible to easily cope with a change in the acid concentration or the alkali concentration of the waste liquid. be able to.
[0043]
Further, when the porous member 4c immersed in the waste liquid is clogged, it can be dealt with by simply replacing the clogged porous member 4c with a new porous member 4c. Very easy to maintain.
[0060]
Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and it goes without saying that modifications and design changes can be appropriately made within the scope of the present invention.
[0061]
【effect】
According to the present invention, waste liquid treatment can be performed slowly without the need for a drive source such as a stirring device and a treatment liquid supply device, and a sudden reaction is caused by directly charging the treatment liquid into the waste liquid. It is possible to provide a simple waste liquid treatment method capable of performing waste liquid treatment without requiring a cooling device for removing heat generated by the waste liquid.
[0062]
According to the present invention, since a stirrer for stirring the waste liquid and the processing liquid, a processing liquid supply device for forcibly sending the processing liquid into the waste liquid, and the like are not required, the power is not required. It is possible to provide a waste liquid treatment apparatus that can perform waste liquid treatment and has a simple device configuration.
[0063]
INDUSTRIAL APPLICABILITY The waste liquid treatment method and waste liquid treatment apparatus of the present invention are suitable for neutralization treatment of waste acid or waste alkali. And the components in the processing solution can be changed.
[Brief description of the drawings]
FIG. 1 is a schematic sectional view showing a waste liquid processing apparatus according to an embodiment of the present invention.
FIG. 2 is an explanatory view showing a bottom of a processing liquid supply tank in the waste liquid processing apparatus shown in FIG.
FIG. 3 is an explanatory vertical sectional view showing a processing liquid supply tank in the waste liquid processing apparatus shown in FIG. 1;
FIG. 4 is an explanatory view showing the bottom of another processing liquid supply tank different from the processing liquid supply tank in the waste liquid processing apparatus shown in FIG. 1;
FIG. 5 is an explanatory diagram showing an operation of a processing liquid supply tank in the waste liquid processing apparatus shown in FIG.
FIG. 6 is an explanatory diagram for explaining that the pressure of the processing liquid in the processing liquid supply tank in the waste liquid processing apparatus shown in FIG. 1 is defined by the height of the processing liquid storage tank.
[Brief description of reference numerals]
DESCRIPTION OF SYMBOLS 1 ... Waste liquid processing apparatus, 2 ... Waste liquid tank, 3 ... Processing liquid storage tank, 4 ... Processing liquid supply tank, 4a ... Tank body, 4b ... Lid member, 4c ... A porous member, 4d mounting member, 4e mounting hole, 5 waste liquid supply port, 6 liquid discharge port, 7 pipe.

Claims (3)

The treatment liquid can be accommodated in the waste liquid stored in the waste liquid tank so that the liquid level is kept constant, and the treatment liquid supply tank that separates the treatment liquid and the waste liquid by the porous member is immersed in the waste liquid. The waste liquid side surface of the porous member according to the gravity of the processing liquid generated by adjusting the amount of the processing liquid so that the level of the processing liquid present in the processing liquid supply tank is higher than the level of the waste liquid And treating the waste liquid with a treatment liquid having an amount of seepage determined in accordance with the surface area of the porous member in contact with the waste liquid. The waste liquid treatment method according to claim 1, wherein the porous member is attached to a treatment liquid supply tank such that a surface area of the porous member that contacts the waste liquid is varied.   A waste liquid tank for storing the waste liquid so that the liquid level is maintained at a constant level, and a processing liquid capable of containing the processing liquid so as to have a liquid level higher than the liquid level of the waste liquid in the waste liquid tank. And a treatment liquid supply tank immersed in the waste liquid in the waste liquid tank so that the waste liquid is separated from the waste liquid by a porous member.

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