JP4614979B2 - Polymer wax peeling waste liquid treatment method - Google Patents

Description

  The present invention relates to a polymer wax peeling waste liquid treatment method capable of substantially eliminating generation of industrial waste, generation of harmful gases, and the like.

In many cases, a polymer wax is applied to a floor surface of a building as a flooring agent for the purpose of protection or aesthetics.
The applied polymer wax as a flooring agent is worn by dust adhesion, mechanical abrasion, abrasion, and the like, and its function and aesthetics are deteriorated. Therefore, it is usually repainted regularly. In this repainting, it is necessary to first peel off the already applied polymer wax, and a large amount of polymer wax peeling waste liquid is generated by the above-described periodic repainting.

The polymer wax peeling method is roughly classified into a wet method using a release agent such as a solvent and a dry method in which no release agent is used or the wax peeled off after application is dried.
In the case of the dry method, since no harmful waste liquid is generated, there is an advantage that it is generally environmentally friendly.
However, in the case of dry stripping, the stripping agent applied prior to stripping is expensive, the initial investment of the mechanical stripping machine is large, or stripping on a relatively small area. There are problems such as not suitable. Also in this case, disposal of the separation waste generated by the separation becomes a problem. Moreover, at the time of manufacture of slaked lime, although the proposal which mixes exfoliation waste into quicklime is also made | formed, since this method requires a lot of quicklime, it has not become a general processing method.

On the other hand, in the case of the wet method, a large amount of polymer wax exfoliation waste liquid is generated, so that disposal considering the influence on the environment is a big problem.
In consideration of such environmental influences, a method has been proposed in which a polymer in a waste liquid is floc precipitated by a flocculant, and this is filtered to clean and drain the liquid as much as possible (for example, Patent Document 1, Patent Document 2, Patent Document 3).

However, even in the case of the cleaned liquid, although the solid matter is excluded, the harmful chemical substance is not necessarily excluded, and therefore, the BOD (Biochemical Oxygen Demand) is large and cannot be directly flowed into the river. Therefore, it will be handled as industrial waste, resulting in high costs due to disposal costs.
In other words, the generation of this industrial waste, in addition to environmental problems, in particular, requires a great deal of cost for this disposal commissioning process, and the burden on the installer for this is a major problem.

JP 2000-301162 A JP 2001-276843 A JP 2001-212598 A

  In the present invention, in particular, in the method for treating a polymer wax peeling waste liquid, it is possible to effectively use a component of the polymer and the peeling liquid contained in the waste liquid as a fuel, and to completely eliminate industrial waste. At the same time, the present invention provides a polymer wax peeling waste liquid treatment method that can eliminate the generation of harmful substances and harmful gases that adversely affect the environment.

  The polymer wax peeling waste liquid treatment method according to the present invention includes a step of adding an acid to a polymer wax peeling waste liquid mixed with a release agent to separate and precipitate a gel-like semi-solid polymer mass only of the polymer in the waste liquid. , A process of extracting polymer lump from the exfoliated waste liquid, a neutralization process of adding an alkaline solution to the remaining waste liquid from which the polymer has been removed by extraction of the polymer lump, and a mixing in which an absorbent material is added to the neutralized remaining waste liquid A vacuum drying step of vacuum drying the remaining waste liquid into which the absorbent material has been charged to obtain a solid, and a step of mixing the solid and the semi-solidified polymer lump to produce a solid fuel. Features.

The present invention also relates to a method for treating a polymer wax peeling waste solution, wherein the polymer is a metal cross-linked styrene acrylic polymer and the release agent is an amine, thereby releasing the metal of the polymer and reducing the cross-linking strength. It is characterized by being a release agent that causes peeling.
The present invention is also directed to a method for treating a polymer wax stripping waste liquid, wherein the acid added to the stripping waste liquid is an organic acid.
The present invention also provides a method for treating a polymer wax peeling waste liquid, wherein the acid added to the peeling waste liquid is an inorganic acid.
The present invention also relates to a polymer wax peeling waste liquid treatment method, wherein the neutralizing alkali solution is at least one of sodium hydroxide, barium hydroxide, sodium bicarbonate, ammonium, sodium carbonate, calcium carbonate, and calcium oxide. It is characterized by that.
Further, the present invention is characterized in that sawdust is used for the absorbent material to be charged in the mixing step.

  In the above-described stripping waste liquid treatment method of the present invention, the polymer is separated and extracted by adding acid from the polymer wax stripping waste liquid, and detoxified by changing the amine in the harmful stripping agent in the stripping waste liquid into a salt. To do. The extracted polymer is used as a solid fuel. Since this polymer is a main component of the flooring agent, it is extracted in a very large amount, so that a large amount of solid fuel is produced, so that a large amount of industrial waste is avoided.

  Moreover, in this invention, the waste liquid which shows acidity by addition of the above-mentioned acid can be made into neutrality or acidity near this by performing the neutralization process which adds an alkaline solution to the washing water of a polymer lump. For this reason, the danger of the handling can be avoided, and generation of harmful gas can be avoided even in the drying process. Further, since the solid can be taken out by drying the waste liquid and this solid can be used as fuel, a very effective waste liquid treatment can be realized.

As described above, according to the method of the present invention, solid fuel can be effectively produced not only from the polymer wax polymer but also from the stripping waste liquid from which the polymer wax is removed, and in the production process and the final residue. , Generation of harmful gases and hazardous substances can be virtually eliminated.
Therefore, the generation of industrial waste is avoided, and environmentally friendly polymer wax peeling waste liquid treatment can be realized.

Hereinafter, embodiments of the polymer wax peeling waste liquid treatment method according to the present invention will be described.
FIG. 1 is a flow diagram of an embodiment of a polymer wax peeling waste liquid treatment method according to the present invention.
In this embodiment, for example, in the repainting of the polymer wax applied to the floor surface, the description will be made from the start of the peeling operation of the polymer wax applied to the floor surface, but the present invention is caused only by the peeling operation. This is a treatment method for the polymer wax peeling waste liquid.

First, at the peeling work site, the floor surface is cleaned prior to the peeling work of the polymer wax of the flooring agent applied to the floor surface (step S1).
Next, wax removal and floor surface cleaning with a release agent having amines are performed (step S2).
As a result, stripping waste liquid containing polymer wax and stripping agent is generated.
The polymer wax peeling waste liquid is stored in a transport container, for example, a so-called plastic container (step S3), and transported to a waste liquid treatment site (step S4).

In this waste liquid treatment site, while stirring the stripped waste liquid that has been transported, an acid such as sulfuric acid, hydrochloric acid, nitric acid, or an organic acid such as acetic acid, malic acid, succinic acid, for example, acetic acid, for example, acetic acid Or dilute sulfuric acid is added to change the amine of the stripping agent into a salt, and the stripping waste liquid is acidified (step S5).
The addition of acetic acid or dilute sulfuric acid separates and precipitates a wax component, that is, a gel-like semi-solid polymer mass containing only a polymer, on the upper layer of the peeling waste liquid. This polymer mass is extracted from the stripping waste liquid (step S6). In this way, the polymer and the remaining waste liquid are separated.

In this embodiment, the polymer lump extracted from the polymer wax peeling waste liquid is washed with clean water (step S7).
Then, neutralization is performed by adding an alkaline liquid to the washing water generated by the polymer washing in step S7 and the remaining waste liquid obtained by extracting the polymer in step S6 (step S8).
By this neutralization treatment, the waste liquid is made almost neutral or weakly acidic.

Next, the absorbent is put into the waste liquid neutralized in step S7, and the waste liquid and the absorbent are mixed (step S9).
Next, the waste liquid into which the absorbent material has been charged is vacuum-dried (step S10). And the mixture of the solid substance contained in the waste liquid and the absorbent material generated by this drying is mixed with the previously washed polymer (step S11) to obtain a solid fuel.

Hereinafter, embodiments of the above-described peeling waste liquid treatment method of the present invention will be described in more detail.
The floor surface cleaning in step S1 in FIG. 1 is a step of removing dust and the like with a vacuum cleaner or the like.
The wax stripping operation in step S2 is a step of applying a stripping agent that strips wax on the floor surface that has been cleaned by removing dust and the like from the floor surface in step S1.
This release agent is a release agent having amines, for example, amines such as 2-amino-ethanol and 2-amino-propanol 15% to 25%, alcohols such as benzyl alcohol and ethylene glycol monobutyl ether, and ethers 60%. , And the balance water. By this release agent, for example, zinc cross-linked styrene acrylic polymer constituting the wax and cross-link metal such as zinc Zn are liberated to reduce the cross-linking strength and cause peeling.

Thereafter, for example, water is further sprayed onto the floor surface, and the stripping waste liquid from which the polymer wax has been stripped is collected using, for example, a squeegee and a vacuum. In this way, stripping waste liquid is generated.
This recovered stripping waste liquid is a waste liquid containing the above-mentioned polymer and a stripping agent, and as a main component, a cross-linked acrylic styrene polymer, a glycol ether solvent and other special solvents, amines, a surfactant, water, Contains dirt.
This waste liquid, for example with wax peeling operation with respect to the floor area ^{70m 2 ~80m} 2, generates about 20 [l] (l). This waste liquid exhibits strong alkalinity, for example, about pH 11 to pH 12.5.

This exfoliated waste liquid is carried to the waste liquid treatment site in steps S3 and S4 shown in FIG.
Then, as explained in step S5 of FIG. 1, while stirring the stripping waste liquid at the waste liquid treatment site, an acid, for example, an inorganic acid such as sulfuric acid, hydrochloric acid or nitric acid, or an organic acid such as acetic acid, malic acid or succinic acid is used. At least one acid selected from acids is added. For example, acetic acid having a concentration of 35 [g / l] is added, for example, 0.7 [l]. In this way, a gel-like semi-solid polymer mass is instantly deposited on the upper layer of the waste liquid. As a result, the amine of the release agent is converted into a salt, for example, an amine acetate and water, by a chemical reaction.
In step S6, a block polymer is extracted from the waste liquid. Since the polymer extracted here is massive, this extraction can be performed very easily.
By extracting the polymer mass, the polymer (that is, the wax component) and the remaining waste liquid are separated.

  The polymer extracted in step S6 is washed with, for example, 5 [l] water in step S7. By this cleaning, the cleaning water after the unnecessary component cleaning adhered to the polymer lump and the remaining waste liquid generated by the polymer extraction in step S6 are accommodated in, for example, the same tank. The waste liquid of about 25 [l] containing this wash water shows acidity with a pH of about 2 to 4.5.

  The washing water washed with the polymer in step S7 and the waste liquid after the polymer extraction in step S6 are neutralized by adding an alkali solution as shown in step S8. This neutralization treatment is performed by adding at least one alkaline solution such as sodium hydroxide, barium hydroxide, sodium bicarbonate, ammonia, sodium carbonate, calcium carbonate, calcium oxide, etc., for example, sodium hydroxide. The pH is almost neutral, for example, slightly acidic. Thus, since the waste liquid which showed strong acidity is made into a neutral or weak acid, danger is eliminated and it becomes an environmentally friendly waste liquid.

Next, in step S8, the waste liquid that has been neutralized is added with the absorbent in step S9 and mixed.
The absorbent material is capable of absorbing moisture and polymer contained in the waste liquid, and can be used in the form of particles or powder that can be easily mixed with combustible materials. Absorbents include, for example, fiber such as sawdust, rice husk, buckwheat husk, coconut husk, paper, thread, hair, fruits, wine, sake, shochu, soybeans, okara, beer, oil, sugar cane, sugarcane, etc. Squeeze, bonito kelp dashi, konjac flying powder, nut shells, activated carbon and the like can be used. Those that are preferably used as absorbents are usually disposed of in large quantities as waste, so that the cost of the absorbent can be reduced.
For example, about 25 [l] of an absorbent is added to about 25 [l] of the neutralized waste liquid. For example, when sawdust is used as an absorbent, about 138 g of sawdust is used for waste liquid 1 [l].
Then, the waste liquid mixed with the absorbent in step S9 is vacuum-dried in step S10 to separate the evaporated components from the waste liquid, and a mixture of the remaining waste liquid solids by the solids contained in the waste liquid and the absorbent is obtained. .
The evaporated components contained in the waste liquid separated here can be recovered again as liquid (separated water) by being condensed by a condenser or the like.
The vacuum drying in step S10 is performed at a vacuum degree of about -0.1 MPa. Further, in this drying treatment, in addition to placing the mixture under vacuum, the mixture can be quickly dried by heating to about 80 ° C.

  As described above, for example, acetic acid is added in step S5, sodium hydroxide is added in step S8, and the remaining waste liquid solid matter extracted by mixing the absorbent in step S9 is mainly sodium acetate. It has been confirmed to be an ingredient. Then, it was confirmed that 88 g (3.5 [g / l]) of the remaining waste liquid solid was taken out from about 25 [l] of the waste liquid containing the washing water.

A solid fuel is formed by mixing the mixture of the remaining waste liquid solid and the absorbent and the polymer separated and extracted in step S6 in step S11. Since this solid fuel burns when the polymer is vaporized, it becomes an effective solid fuel by causing the absorbent mixed in step S9 to act as a combustion aid. Further, as a combustion aid, for example, by further mixing paper, sawdust and the like excellent in combustibility, a more effective solid fuel can be obtained. The combustion aid mixed with the solid fuel may be the same as or different from the absorbent mixed in step S9 described above.
Further, the solid fuel can be used by cutting it into an arbitrary small chip shape, that is, a shape that is easy to burn.

  In addition, by using an organic acid such as acetic acid as the acid added in step S5, the BOD of the waste liquid separated in step S6 may be larger than when an inorganic acid such as sulfuric acid is used. However, the wastewater generated during the vacuum drying in step S10 can be easily treated by a septic tank such as an ordinary explosive activated sludge method after radical decomposition. For this reason, it is possible to easily lower the BOD of the waste water to such an extent that it can be discharged into the river and to purify the waste water.

In addition, when an inorganic acid is used as the acid to be added in step S5, it is possible to lower the BOD of the waste liquid separated in step S6. However, after radical decomposition, a normal explosion-type activated sludge method or the like can be used. Depending on the septic tank, it may be difficult to process.
Even when an inorganic acid is used as the acid added in step S5, for example, neutralization is performed using dilute sulfuric acid as the acid added in step S5 and barium hydroxide as the alkaline solution added in step S8. Process. Then, dilute sulfuric acid and barium hydroxide can be reacted to generate barium sulfate that is sparingly soluble in water as a salt. By separating the hardly soluble salt by filtration with a filter or the like, treatment in a septic tank such as a normal explosion type activated sludge method after radical decomposition becomes possible.
For this reason, the wastewater BOD can be purified to such an extent that the BOD of the wastewater can be easily lowered and discharged into the river by a septic tank such as a normal explosion type activated sludge method.
Moreover, even in the insoluble salt separated from the above-described waste liquid, for example, barium sulfate can be traded as a valuable resource and can be reused, so that generation of industrial waste can be avoided.
In addition to the combination of dilute sulfuric acid and barium hydroxide, any combination of acid and alkali may be used as long as the salt generated by the reaction between the acid and alkali shows poor solubility in water, and is not limited to dilute sulfuric acid and barium hydroxide. In addition, any acid and alkali can be used in combination.

In the stripping waste liquid treatment method of the above-described embodiment, the polymer is separated and extracted from the polymer wax stripping waste liquid by addition of an acid, and the amine in the harmful stripping agent in the stripping waste liquid is changed to a salt. Can be detoxified.
The extracted polymer can be used as a solid fuel. Further, since this polymer is the main component of the flooring agent, it is extracted in a very large amount. For this reason, generation of industrial waste due to this polymer can be avoided by producing a large amount of solid fuel from the polymer.

  As described above, the solid fuel obtained by the stripping waste liquid treatment method of the present invention is effective as a fuel for various manufacturing factories (for example, a paper mill) using waste plastic as a fuel, a so-called waste plastic power plant, and the like.

Next, a processing apparatus for performing the above-described polymer wax peeling waste liquid processing method according to the present invention, particularly a vacuum drying apparatus for performing the vacuum drying in step S10 will be described.
FIG. 2 is a schematic configuration diagram of a vacuum drying apparatus that performs vacuum drying according to the present embodiment.

In FIG. 2, the present apparatus includes a heat dryer 10 that is installed in a horizontal shape for treating waste liquid. The outer peripheral portion (see FIG. 3) of this heat dryer has a double structure, and is formed by an inner cylinder 11 having a predetermined volume and a jacket 12 formed on the outer peripheral portion of the inner cylinder 11.
The above-described heat dryer is provided with a rotating shaft 14 that passes through the center of one surface. The rotating shaft 14 is connected to a driving source (not shown) and has a structure that can rotate forward and backward.

  A hopper 15 for charging the waste liquid is provided at the top of the heating dryer 10. A pressure lid 16 is provided at the opening of the hopper 15 so as to be openable and closable.

  The inside of the jacket 12 of the heat dryer 10 has a structure in which heated steam can be supplied from the boiler 30 through the pipe 41. The rotating shaft 14 has a structure capable of supplying heated steam through the rotary joint 18 connected to the pipe 41 and the end of the rotating shaft 14.

  The jacket 12 and the rotary joint 18 of the rotary shaft 14 are connected to a drain pipe 42 for discharging the supplied heated steam, and the heated steam is discharged to the outside of the heating dryer 10. .

  As shown in FIG. 2, the heat dryer 10 is connected to a steam inlet 23 a of a jet condenser 23 for decompressing the inside of the heat dryer 10 by a pipe 43 connected to the side surface of the hopper 15.

The Zet capacitor 23 is designed so that the function of the capacitor and the function of the vacuum pump can be performed by a single device. In addition to the steam inlet port 23a, the jet condenser 23 is provided with a driving water inlet port 23b and a discharge port 23c. A pipe 45 is connected to the drive water inlet 23b, and a pipe 46 is connected to the discharge port 23c.
Then, the jet condenser 23 circulates the liquid from the driving water inlet 23b to the discharge outlet 23c, thereby reducing the pressure inside the heating dryer 10 through the pipe 43 connected to the steam inlet 23a by the action of the vacuum pump. It has a structure that can.

  A pipe 46 connected to the discharge port 23 c of the Zet condenser 23 communicates with the circulating water tank 25. Further, the pipe 44 connected to the driving water inlet 23b is connected to the pump 26. The pump 26 and the circulating water tank 25 are connected by a pipe 44.

The circulating water stored in the circulating water tank 25 is pushed up in the pipe 45 by the pump 26 and rises above the jet condenser 23. And it falls in the piping 44, flows in from the drive water inlet 23b provided above the jet condenser 23, and is discharged | emitted from the discharge outlet 23c.
Moreover, the vapor | steam introduce | transduced into the jet condenser 23 from the vapor | steam inlet 23a can be collect | recovered again as a liquid (separated water) by being cooled and condensed by circulating water. Then, the separation water is discharged from the discharge port 23 c through the pipe 46 to the circulating water tank 25 while being mixed with the circulating water in the Zet condenser 23.

As described above, the circulating water stored in the circulating water tank 25 passes through the pipes 44, 45, 46 and circulates in the circulating water tank 25, the pump 26, and the jet condenser 23.
Further, since the separated water condensed in the jet condenser 23 is discharged together with the circulating water to the circulating water tank 25, the circulating water in the circulating water tank 25 is stored in a state where the evaporation components of the waste liquid are mixed.

A water supply pipe 47 for supplying cold water into the circulating water tank 25 is connected to the circulating water tank 25. When the temperature of the circulating water in the circulating water tank 25 rises, the temperature of the circulating water can be lowered by supplying cold water from the water supply pipe 47.
An overflow pipe 48 is connected to the circulating water tank 25 so that the circulating water does not exceed a predetermined amount.
As described above, the circulating water tank 25 has a structure in which the temperature and amount of the circulating water in the circulating water tank 25 can be kept constant by supplying cold water from the water supply pipe 47 and discharging the cold water from the overflow pipe 48. It is.

Next, the heating dryer 10 used in the vacuum drying apparatus of FIG. 2 will be described with reference to FIGS. 3A, 3B, and 3C.
A plan view of the heat dryer 10 is shown in FIG. 3A. 3A is a cross-sectional view taken along the line AA ′ in FIG. 3A, and FIG. 3C is a cross-sectional view taken along the line BB ′.

3B and 3C, the heat dryer 10 has a double structure on the outer peripheral portion, and is formed of an inner cylinder 11 having a predetermined volume and a jacket 12 formed on the outer peripheral portion of the inner cylinder 11.
Heated steam can be supplied from the outside between the jacket 12 of the heat dryer 10 and the inner cylinder 11, and the inside of the inner cylinder 11 can be heated.

A rotating shaft 14 is provided on one surface of the above-described heating dryer 10 so as to penetrate the center portion. The rotating shaft 14 is connected to a driving source (not shown) and is rotated forward and backward.
The rotating shaft 14 is connected to a stirring blade 19 having a hollow inside.
The stirring blade 19 is constituted by a sleeve 19a provided concentrically around the rotating shaft 14 at a predetermined interval, and arm pipes 19b are radially attached to the outer periphery thereof. A blade 19c having a predetermined shape facing the inner wall surface of the heat dryer 10 is provided at the tip of the arm pipe 19b.
Then, by rotating the rotating shaft 14, the inside of the heat dryer 10 can be stirred by the stirring blade 19.

A rotary joint 18 is provided at the end of the rotating shaft 14. And it has the structure which can supply heating steam to the space in the rotating shaft 14 from the rotary joint 18 through the piping 41 from the boiler 30 (refer FIG. 2).
Further, the heated steam supplied to the rotating shaft 14 is introduced into the sleeve 19a and the arm pipe 19b. For this reason, the content of the heat dryer 10 which contacted the arm pipe 19b can be heated.
A drain pipe 42 for discharging the supplied heated water vapor is connected to the rotary joint 18 at the rotary shaft 14, and the heated water vapor supplied from the rotary shaft 14 into the sleeve 19a and the arm pipe 19b can be discharged to the outside. It has become.

  Moreover, in the above-mentioned heating dryer 10, the surface opposite to the surface through which the rotating shaft 14 passes is constituted by a lid 17 that can be opened and closed. By opening and closing the lid 17, the rotating shaft 14 and the stirring blade 19 can be accommodated in the heating dryer 10.

A hopper 15 for charging the waste liquid is provided at the top of the heating dryer 10. A pressure lid 16 is provided at the opening of the hopper 15 so as to be openable and closable. A pipe 43 is connected to the side wall of the hopper 15.
The pipe 43 connected to the hopper 15 is connected to a Zet condenser 23 (see FIG. 2) that decompresses the inside of the heating dryer 10.

  Next, the waste liquid drying method using the vacuum drying apparatus shown in FIG. 2 and FIGS.

  First, the lid 17 is opened, the rotary shaft 14 is inserted into one surface of the heat dryer 10, and the stirring blade 19 is accommodated in the dryer. And the rotating shaft 14 and the rotary joint 18 are connected, and the cover body 17 is closed.

Next, the pressure lid 16 of the heating dryer 10 is opened, and the waste liquid neutralized in step S8 and the absorbent material in step S9 are put into the heating dryer 10. At this time, either one of the waste liquid and the absorbent material may be introduced first, or at the same time. Further, the waste liquid and the absorbent material may be mixed in advance, and then charged into the heating dryer 10.
It is preferable that the amount of the waste liquid and the absorbent that are put into the heating dryer 10 is about half of the volume in the dryer.

  Next, the stirring blade 19 is rotated by a drive unit (not shown) connected to the rotating shaft 14 to stir the charged waste liquid and absorbent. The rotation speed and rotation direction of the stirring blade at this time can be arbitrarily adjusted.

  Next, heated steam is introduced from the boiler 30 into the jacket 12 and the stirring blade 19 through the pipe 41. As a result, the waste liquid and the absorbent placed in the heating container are heated with stirring, and the temperature is increased to about 80 ° C.

  Next, the pump 26 is driven to circulate the circulating water in the circulating water tank 25, and the circulating water is circulated from the driving water inlet 23b of the jet condenser 23 to the discharge outlet 23c, and the jet condenser 23 is used as a vacuum pump. . Thereby, the heating dryer 10 is pressure-reduced through the piping 43 connected to the steam inlet 23a, and the vacuum degree inside the heating dryer 10 is reduced to about -0.1 MPa.

  As described above, when the pressure in the heat dryer 10 decreases and the waste liquid is heated, the evaporation component contained in the input waste liquid starts to evaporate. Then, the steam is sucked out of the heating dryer 10 through the pipe 43 connected to the hopper 15 by sucking the inside of the container with the Zet condenser 23.

Next, the steam discharged from the heat dryer 10 passes through the pipe 43 and flows into the steam inlet 23 a of the jet condenser 23.
At this time, the steam that has flowed into the jet condenser 23 is cooled by the circulating water flowing from the drive water inlet 23b to the discharge outlet 23c. The cooled steam is condensed and becomes liquid (separated water) again, and is discharged from the discharge port 23c together with the circulating water. And it is received by the circulating water tank 25 through the piping 46.

Next, in the waste liquid and the absorbent material charged in the heating dryer 10, the above-mentioned vacuum drying is performed until the evaporated component is separated from the waste liquid, thereby separating the solid content and the evaporated component from the waste liquid. Only minutes can be left in the dryer.
Moreover, an absorber remains with solid content in a heat dryer.
As described with reference to the flow chart of FIG. 1, the solid content and the absorbent material thus obtained are made into a solid fuel through, for example, step S11 together with the polymer extracted in step S6.

When the waste liquid neutralized in step S8 is further dried after the waste liquid has been dried by the vacuum drying method described above, the above-described absorbent material can be used repeatedly. For this reason, the waste liquid can be vacuum-dried continuously by adding the waste liquid into the heat dryer 10 and repeating the above-described vacuum drying process.
At this time, the waste liquid can be continuously vacuum-dried by repeating the above-described vacuum drying process by adding the waste liquid while keeping the temperature and the degree of vacuum in the dryer.
Thereby, a large amount of waste liquid can be dried with one vacuum drying apparatus mentioned above.

Moreover, from the above-mentioned vacuum drying apparatus, the circulating water and the separated water are discharged out of the apparatus as drainage due to the overflow of the circulating water tank 25.
Since this drainage contains evaporation components contained in the waste liquid, for example, it cannot be discharged as industrial waste into rivers or the like unless it meets the national and prefectural drainage standards. However, this waste water can be purified until it can be discharged into a river by treating it with an explosion type septic tank.
However, if the wastewater discharged from the above-mentioned vacuum drying apparatus satisfies the national and prefectural wastewater standards, it can be discharged directly into a river or the like.

(Example)
Hereinafter, the above-described peeling waste liquid treatment method of the present invention will be described with reference to examples.

Example 1
First, 750 [ml] of dilute sulfuric acid having a concentration of 36% (pH 0.29) was added to the stripping waste liquid 10 [l] (pH 10.39) obtained in steps S1 to S4.
Then, the aggregated polymer mass was extracted by adding dilute sulfuric acid. At this time, a polymer mass of 1485 [g] was obtained. Further, 8.5 [l] of a waste liquid having a pH of 1.93 was obtained as a waste liquid after polymer extraction.
Next, the extracted polymer mass was washed with 2 [l] of water. And the water used for this washing | cleaning was mixed with the waste liquid after the said polymer extraction.
Next, 12 [l] barium hydroxide solution (concentration 4%, pH 11.1) in which 300 [g] barium hydroxide was dissolved was added to the waste liquid after the polymer extraction. Then, barium sulfate hardly soluble in water generated by the addition of barium hydroxide was filtered to separate barium sulfate from the waste liquid.
Next, 3036 [g] of sawdust as an absorbent was mixed with the waste liquid 22 [l] discharged by the above method.
Next, the above-described waste liquid mixed with the absorbent was vacuum-dried under the conditions of a vacuum degree of −0.1 [MPa] and a temperature of 80 [° C.] using the above-described vacuum drying apparatus. In the above-described vacuum drying apparatus, 110 [l] of circulating water was stored in the circulating water tank 25 in advance.
Next, a solid fuel was obtained by mixing the mixture of the remaining waste liquid solid material and the absorbent obtained by vacuum drying with the polymer mass described above.
Further, the mixture of separated water and circulating water by vacuum drying discharged in the above method was inspected as the waste water of Example 1.

(Example 2)
First, a malic acid aqueous solution 4 [l having a concentration of 15% (pH 2.07) in which 400 [g] malic acid is dissolved with respect to the stripping waste liquid 10 [l] (pH 10.39) obtained in steps S1 to S4. ] Was added.
And the agglomerated polymer lump was extracted by adding malic acid. At this time, a polymer mass of 1900 [g] was obtained. Moreover, 12.25 [l] of pH 3.6 waste liquid was obtained as the waste liquid after polymer extraction.
Next, the extracted polymer mass was washed with 2 [l] of water. And the water used for this washing | cleaning was mixed with the waste liquid after the said polymer extraction.
Next, 254 [g] of sodium hydrogen carbonate (bicarbonate) was added to 14.25 [l] of the waste liquid after the polymer extraction.
Next, 1966 [g] of sawdust as an absorbent was mixed with the waste liquid.
Next, the above-described waste liquid mixed with the absorbent was vacuum-dried under the conditions of a vacuum degree of −0.1 [MPa] and a temperature of 80 [° C.] using the above-described vacuum drying apparatus. In the above-described vacuum drying apparatus, 110 [l] of water was stored in the circulating water tank 25 in advance.
Next, a solid fuel was obtained by mixing the mixture of the remaining waste liquid solid material and the absorbent obtained by vacuum drying with the polymer mass described above.
Further, the mixture of separated water and circulating water by vacuum drying discharged in the above method was inspected as waste water of Example 2.

(Comparative Example 1)
First, 750 [ml] of dilute sulfuric acid having a concentration of 36% (pH 0.29) was added to the stripping waste liquid 10 [l] (pH 10.39) obtained in steps S1 to S4.
Then, the aggregated polymer mass was extracted by adding dilute sulfuric acid. At this time, a polymer mass of 1485 [g] was obtained. Further, 8.5 [l] of a waste liquid having a pH of 1.93 was obtained as a waste liquid after polymer extraction.
Next, the extracted polymer mass was washed with 2 [l] of water. And the water used for this washing | cleaning was mixed with the waste liquid after the said polymer extraction.
Next, 12 [l] barium hydroxide solution (concentration 4%, pH 11.1) in which 300 [g] barium hydroxide was dissolved was added to the waste liquid after the polymer extraction. Then, barium sulfate hardly soluble in water produced by the addition of barium hydroxide was filtered to separate barium sulfate from the waste liquid.
The waste liquid obtained by the above method was inspected as the waste water of Comparative Example 1.

(Comparative Example 2)
First, a malic acid aqueous solution 4 [l having a concentration of 15% (pH 2.07) in which 400 [g] malic acid is dissolved with respect to the stripping waste liquid 10 [l] (pH 10.39) obtained in steps S1 to S4. ] Was added.
And the agglomerated polymer lump was extracted by adding malic acid. At this time, a polymer mass of 1900 [g] was obtained. Moreover, 12.25 [l] of pH 3.6 waste liquid was obtained as the waste liquid after polymer extraction.
Next, the extracted polymer mass was washed with 2 [l] of water. And the water used for this washing | cleaning was mixed with the waste liquid after the said polymer extraction.
Next, 254 [g] of sodium bicarbonate (sodium bicarbonate) was added to the waste liquid after the polymer extraction.
The waste liquid obtained by the above-described method was inspected as the waste water of Comparative Example 2.

The wastewaters of Examples 1 and 2 and Comparative Examples 1 and 2 were inspected by requesting the environmental measurement certification business registration, Gunma Prefecture Governor No. 7, and Gunma Analysis Center.
Table 1 shows the drainage standards for Gunma Prefecture as an example of the inspection results and drainage standards. In Table 1, less than indicates the lower limit of determination.

As shown in Table 1, the wastewater of Example 1 has a BOD (Biochemical Oxygen Demand) of 280 [mg / l] and COD (Chemical Oxygen Demand) of 88 [mg / l]. The waste water of BOD was 730 [mg / l] and COD was 220 [mg / l].
Further, the wastewater of Comparative Example 1 has a BOD of 12000 [mg / l] and COD of 47000 [mg / l], and the wastewater of Comparative Example 2 has a BOD of 38000 [mg / l] and a COD of 21000 [mg / l]. ]Met.

From this result, the values of BOD and COD were lower in Examples 1 and 2 that were vacuum dried using sawdust as the absorbent described above than in Comparative Examples 1 and 2 that were not vacuum dried. I understand.
Therefore, by performing vacuum drying using an absorbent, it is possible to sufficiently reduce the BOD and COD of the waste water.

In Examples 1 and 2, the contents of zinc and phosphorus are clearly lower than those in Comparative Examples 1 and 2. This is considered to be because heavy metals such as zinc contained in the waste water were adsorbed on the sawdust due to the use of sawdust as the absorbent during the vacuum drying described above.
For this reason, by using a porous material that can adsorb heavy metals, such as sawdust, as an absorbent during vacuum drying, harmful substances in wastewater can be adsorbed and the amount of harmful substances discharged can be reduced. Can be reduced.

Moreover, as shown in Table 1, Example 1 which used the inorganic acid in step S5 became a low value of BOD and COD compared with Example 2 which used the organic acid in step S5.
Thus, BOD and COD of waste water can be reduced by using an inorganic acid as the acid added in step S5.

In addition, the drainage standards that can be discharged into rivers in Gunma Prefecture for the drainage inspection results in Examples 1 and 2 are pH 5.8 to 8.6, BOD 60 [mg / l] or less, COD 60 [mg / l]. Hereinafter, it is determined that it is SS70 [mg / l] or less.
For this reason, in Examples 1 and 2 described above, wastewater discharged due to overflow during vacuum drying cannot be discharged into the river as it is because both BOD and COD are higher than the reference value.

However, it has been found that the substances increasing the BOD and COD of the waste water in Examples 1 and 2 are mainly ethylene glycol monobutyl ether, benzyl alcohol, and 2-aminoethanol contained in the separated water.
For this reason, BOD and COD can be reduced to the level which can be discharged | emitted to a river by purifying the circulating water containing separation water in an explosion-type septic tank using a normal activated sludge method after radical decomposition.

  Therefore, in the separation waste liquid treatment method of the present invention described above, the recovered separated water generated in the drying treatment for the waste liquid described above can be treated by a septic tank such as a normal explosive activated sludge method after radical decomposition. it can. And by this process, waste water can be purified to such an extent that it can be discharged into the river.

Moreover, in the above-mentioned vacuum drying, foaming that occurs when heating and mixing in the heat dryer can be suppressed by mixing the absorbent with the waste liquid in step S9.
In particular, since the inside of the heat dryer 10 is brought into a vacuum state by the zette condenser 23, foaming due to the cleaning agent component contained in the waste liquid is likely to occur. Further, when the waste liquid is foamed in this manner, the waste liquid is foamed in the heat dryer 10 and the degree of vacuum is lowered.
For this reason, when the waste liquid is foamed, a predetermined degree of vacuum cannot be obtained, and it takes time to dry the waste liquid. Furthermore, since the waste liquid is foamed, the volume of the foam in the heat dryer 10 is increased, and the pressure in the dryer is not reduced, so that the waste liquid drying process is stopped.
Moreover, when the generated foam enters the pipe 43, the solid content contained in the foam of the waste liquid is discharged together with the separated water.
For this reason, the circulating water discharged to the circulating water tank 25 is discharged while containing the main components other than the polymer together with the separated water. For this reason, as shown in Comparative Examples 1 and 2 in Table 1, it is considered that BOD, COD and the like in the waste water increase.

  However, in Examples 1 and 2, as described above, by mixing the absorbent, foaming of the waste liquid can be suppressed, and the problem due to foaming of the waste liquid can be solved.

  In the drying step, the vapor separated from the waste liquid is condensed by a condenser and taken out as separated water. For this reason, the evaporation component contained in the peeling waste liquid can be dried without generating gas.

As described above, according to the method of the present invention, solid fuel can be effectively produced not only from the polymer wax polymer but also from the stripping waste liquid from which the polymer wax is removed, and in the production process and the final residue. , Generation of harmful gases and hazardous substances can be virtually eliminated.
Therefore, the generation of industrial waste is avoided, and environmentally friendly polymer wax peeling waste liquid treatment can be performed.

  Further, according to the method of the present invention, in the treatment of the polymer wax peeling waste liquid, the polymer component generated in a large amount can be separated from the waste liquid as a pure lump, which can be used as a fuel. As described above, since the polymer component contained in the waste liquid is completely abolished to become industrial waste, a great environmental benefit can be brought about.

  Furthermore, in recent years, the disposal cost of industrial waste has been increasing, and in the method of the present invention, the stripping waste liquid is made harmless by a simple method and produced as a valuable fuel. The economic burden of the enforcer can be converted into economic benefits.

  In addition, since the generation of toxic gas can be avoided in the fueling process, there are many benefits such as the provision of a device for eliminating toxic gas and the simplification of the device. It will be.

  The present invention is not limited to the above-described configuration, and it goes without saying that various other configurations can be employed without departing from the gist of the present invention described in the claims.

It is a figure which shows the flow of an example of the peeling waste liquid processing method of the polymer wax by this invention. It is a schematic block diagram of the vacuum drying apparatus used for vacuum drying. A It is a top view of the heat dryer used with a vacuum dryer. B is a cross-sectional view illustrating a configuration along the line AA ′ of the heat dryer illustrated in FIG. 3A. 3C is a cross-sectional view illustrating a configuration along the line BB ′ of the heat dryer illustrated in FIG. 3A.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Heating dryer, 11 Inner cylinder, 12 Jacket, 14 Rotating shaft, 15 Hopper, 16 Pressure lid, 17 Lid body, 18 Rotary joint, 19 Stirring blade, 19a Sleeve, 19b Arm pipe, 19c Blade, 23 Zet condenser, 23a Steam inlet, 23b Drive water inlet, 23c Discharge port, 25 Circulating water tank, 26 Pump, 30 Boiler, 41, 42, 43, 44, 45, 46 Piping, 47 Water supply piping, 48 Overflow piping

Claims (6)

A step of adding an acid to a polymer wax peeling waste liquid mixed with a release agent to separate and precipitate a polymer-only semi-solid polymer mass only in the waste liquid;
Extracting the polymer mass from the stripping waste liquid;
A neutralization treatment step of adding an alkaline solution to the remaining waste liquid from which the polymer has been removed by extraction of the polymer mass;
A mixing step of introducing an absorbent into the remaining waste liquid that has been neutralized;
A vacuum drying step of vacuum drying the remaining waste liquid charged with the absorbent material to obtain a solid,
A method for treating a polymer wax peeling waste liquid, comprising the step of mixing the solid and the semi-solidified polymer mass to produce a solid fuel. The polymer is a metal cross-linked styrene acrylic polymer,
2. The polymer according to claim 1, wherein the release agent is an amine, and release of the polymer wax is a release agent that reduces the cross-linking strength due to liberation of the metal and causes release. 3. Wax peeling waste liquid treatment method.   The method for treating a polymer wax peeling waste liquid according to claim 1 or 2, wherein the acid added to the peeling waste liquid is an organic acid.   3. The polymer wax peeling waste liquid treatment method according to claim 1, wherein the acid added to the peeling waste liquid is an inorganic acid.   The alkali solution for the neutralization treatment is at least one of sodium hydroxide, barium hydroxide, sodium hydrogen carbonate, ammonia, sodium carbonate, calcium carbonate, and calcium oxide. Method for treating the polymer wax peeling waste liquid. The method for treating a polymer wax peeling waste liquid according to any one of claims 1 to 4, wherein sawdust is used for the absorbent material introduced in the mixing step.

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