JP2007222710A - Method and apparatus for regenerating waste liquid of printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily separate washing waste liquid containing ink pigment, water and washing liquid used in a printer with a single device. <P>SOLUTION: In this method for regenerating the waste liquid containing ink pigment, organic washing liquid and water by charging the waste liquid into a waste liquid regeneration apparatus having a regeneration vessel, an emulsion treating agent for breaking emulsion mainly consisting of water and washing liquid and coagulating ink pigment particles is added to the waste liquid, then the waste liquid is separated into regenerated washing liquid, ink pigment and water by using a gravity settling method. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a method for regenerating waste liquid generated when cleaning a printing press component such as a printing press blanket cylinder, particularly in a system in which three components of an ink pigment, an oily cleaning liquid, and water are mixed. The present invention relates to a waste liquid recycling method and a waste liquid recycling apparatus for a printing press, in which three components are separated by a simple device. More specifically, in a system containing sludge-like substances generated when the waste liquid mixed with the three components is vigorously stirred, even in a situation where the three components cannot be separated only by physical action such as gravity field and filtration, The present invention relates to a waste liquid recycling method and a waste liquid recycling apparatus for a printing press that can easily separate the three components.

  Waste liquid comes out when cleaning the blanket cylinder and impression cylinder of the printing press. However, in consideration of the environment and to reduce the running cost of cleaning agents, there is a movement to recycle this waste liquid and reuse the cleaning liquid. ing.

  The lowest cost method for regeneration is the sedimentation method. FIG. 4 shows a schematic configuration of a waste liquid regenerating apparatus that separates the pigment mixed in the cleaning liquid by a sedimentation method (see Patent Document 1). As shown in FIG. 4, the conventional waste liquid regenerating apparatus 51 includes a container 53 for storing cleaning waste liquid (waste liquid) 52, and a bottom discharge pipe 54 is connected to the bottom wall of the container 53. A side discharge pipe 55 is connected to the. Further, of these discharge pipes 54 and 55, a concentrated waste liquid recovery container 56 is disposed below the outlet of the bottom discharge pipe 54, and a regenerated cleaning liquid recovery container 57 is disposed below the outlet of the side discharge pipe 55. ing. In addition, an opening / closing valve 58 is connected to the passage of one bottom discharge pipe 54, an opening / closing valve 59 is connected to the upstream side of the passage of the other side discharge pipe 55, and a filter 60 is arranged downstream thereof. It is installed.

  In the waste liquid regenerating apparatus 51 configured in this way, the waste liquid 52 after washing the blanket cylinder of the printing press is stored in the container 53, and a chemical that promotes the sedimentation of the ink pigment (also simply referred to as pigment) 61 is used as the waste liquid 52. Is added to the bottom of the container 53. Subsequently, the settled ink pigment, that is, the concentrated waste liquid 63 is recovered from the bottom discharge pipe 54 to the concentrated waste liquid collection container 56, and the supernatant liquid of the waste liquid 52 is filtered through the side discharge pipe 55 through the filter 60 to remove the ink pigment 61. Then, it is recovered in the regenerated cleaning liquid recovery container 57. The cleaning liquid 62 thus obtained is reused.

However, in this method, not only the purity of the regenerated cleaning liquid is insufficient, but the ink pigment 61 is not sufficiently settled depending on the combination of the ink and the cleaning liquid, and the filter 60 is clogged immediately. There was a problem that replacement or cleaning had to be performed frequently.
On the other hand, in the field of electrophotography, a wet development method in which a charged toner dispersed in a solvent is made to adhere to an electrostatic latent image by electrophoresis and visualized is partially adopted. In this system, a method of electrically removing charged toner particles from the waste liquid after cleaning has also been proposed (Patent Document 2).
Non-Patent Document 1 presents a toner particle removing device.

Japanese Patent No. 3586656 JP-A-53-10440 Kurotori et al., “Full-color electrophotographic printer using liquid developer”, Japan Hardcopy '96 Proceedings, 1996, p. 153-156

  However, in the techniques disclosed in Patent Document 2 and Non-Patent Document 1, it is not assumed that conductive water is mixed. For example, the apparatus of Non-Patent Document 2 separates moisture using the difference in specific gravity between the carrier liquid and water when the recovered carrier liquid contains water. Not only is it necessary, it is inevitable that separation takes a long time.

In recent years, restrictions on the use of organic solvents are becoming stricter, and after using a minimum amount of organic solvent-based cleaning agent at the time of cleaning, a method of finishing cleaning with water is increasing. In this case, the cleaning waste liquid is a liquid in which three components of an organic solvent-based cleaning agent, a pigment, and water are mixed. However, the regeneration apparatus in FIG. 4 does not assume the regeneration of the three-component cleaning waste liquid mixed with water.
When the cleaning waste liquid containing the above three components is vigorously stirred, an emulsion mainly composed of a cleaning agent component and water is formed as a bulky sludge substance. Even if the waste liquid containing the emulsion, which is a bulky sludge-like substance, is to be treated by gravity sedimentation, the emulsion is hardly reduced only by standing, so that the cleaning liquid that can be regenerated and reused is extremely small. In addition, when the filtration operation is performed to separate the emulsion from the cleaning liquid and water, not only the ink pigment but also the emulsion is filtered as a solid content on the filter, and the sludge emulsion immediately causes the filter to be clogged. It takes a lot of labor and time to filter the waste liquid.
In addition, in order to discard the filtered emulsion, it must be treated as industrial waste, and there is a problem that processing costs are incurred.

  The present invention has been made in view of such circumstances, and the waste liquid of a printing press that can easily separate the cleaning waste liquid containing ink pigment, water, and cleaning liquid used in the printing press with a single device. An object of the present invention is to provide a recycling method and a waste liquid recycling apparatus.

In order to solve the above problems, the waste liquid recycling method and the waste liquid recycling apparatus of the present invention employ the following means.
The waste liquid recycling method for a printing press according to the present invention is a waste liquid recycling method for recycling a waste liquid containing an ink pigment, an organic cleaning liquid, and water into a recycling apparatus having a recycling container, wherein the waste liquid is contained in the recycling container. Has a separation step of separating the regenerated washing liquid, ink pigment, and water using gravity sedimentation, and before the separation step, destroys the emulsion mainly composed of water and the washing liquid and agglomerates the ink pigment particles. It has the emulsion processing agent addition process which adds a processing agent to the said waste liquid, It is characterized by the above-mentioned.
In the waste liquid recycling method for a printing press according to the present invention, the ink pigment is agglomerated with the function of breaking the emulsion in order to separate the system containing the three components of the ink pigment, the organic cleaning liquid, and water with a single device. A substance having at least a function (hereinafter referred to as “emulsion treating agent”) is added to the washing waste liquid and treated by gravity sedimentation. By adding this emulsion treatment agent, the volume of the bulky sludge substance in which the emulsion mainly composed of the cleaning liquid component and water produced when the waste liquid containing the above three components is vigorously stirred is reduced to 1/5 or less, preferably 1 / Since the volume can be reduced to 10 or less, it is possible to quickly and efficiently separate the three components of the ink pigment, the cleaning agent, and water by the gravity sedimentation method regardless of the stirring state of the waste liquid. The ink pigment is deposited at the interface between the lower aqueous phase and the upper detergent phase. In the ink, the pigment particles are finely dispersed to about 1 μm or less, but the ink pigment deposited on the interface is agglomerated particles due to the effect of the emulsion treating agent and can be easily separated by filtration.

The emulsion treatment agent preferably contains a nonionic surfactant as a main component.
A surfactant structurally has both a hydrophilic group and a hydrophobic group of a certain size in the molecule, but the hydrophilic group is a nonionic surfactant that does not ionically dissociate in water. There are positively charged cationic surfactants and negatively charged anionic surfactants. When the cationic and anionic surfactants are charged by themselves, they have ions (counter ions) with opposite charging characteristics to their own charging characteristics. Release into water.
The emulsion treating agent of the present invention is required to exhibit an action of aggregating pigment particles at the same time as breaking the emulsion. Since the ink is an oil-based ink, the pigment is generally a surface having high affinity with the oil-based ink, that is, hydrophobic. The ionic surfactant is preferably a nonionic surfactant that is strong in ionicity and strong in hydrophilicity, hardly adsorbed on the surface of the hydrophobic pigment and does not dissociate in that respect.

The nonionic surfactant is a copolymer having a polyoxyethylene chain as a part of the structure, and preferably has an HLB of 10 or less.
Polyoxyethylene chain (CH ₂ CH ₂ O) _n obtained by addition polymerization of ethylene oxide CH ₂ CH ₂ O functions as a hydrophilic group, and is a nonionic surfactant having this polyoxyethylene chain as part of the structure The agent can be made into a surfactant having the desired physical properties by changing the kind of hydrophobic group or the number of added moles of alkylene oxide.
A balance between hydrophilicity and hydrophobicity expressed as a numerical value is HLB (Hydrophile-Lipophile Balance), which is a representative index representing the basic physical properties of a nonionic surfactant. A surfactant having no hydrophilic group has HLB = 0, and a surfactant having a hydrophilic group such as polyethylene glycol has HLB = 20. Therefore, the HLB range of the nonionic surfactant is 0-20. This HLB value means that the smaller the number, the stronger the hydrophobicity, and the larger the number, the stronger the hydrophilicity.

  When the waste liquid containing the ink pigment, the organic cleaning liquid, and the three components of water is vigorously stirred, a bulky sludge substance in which an emulsion mainly composed of the cleaning liquid component and water is aggregated is generated. There are O / W type and W / O type emulsions, but either O / W type or W / O type emulsion is always formed even if the combination of ink type and cleaning liquid type changes. Although it has not been confirmed, by adding an emulsion treatment agent mainly composed of a nonionic surfactant having an HLB of 10 or less, preferably 8 or less, the generation of the sludge can be suppressed or generated. It has been experimentally found that the volume of can be reduced to 1/5 or less, preferably 1/10 or less. However, the reason for the effectiveness of the emulsion treatment agent of the present invention is not clear because it is hardly affected by the type of ink used in the printing press or the type of cleaning liquid. ing.

It is presumed that the surface-active substances contained in the ink stabilize the emulsion in the waste liquid, but if this surface-active substance has HLB, it probably has a medium to high HLB value. In addition, the addition of an emulsion treatment agent having a low HLB value such as an HLB of 10 or less, preferably 8 or less causes the emulsion to become unstable or break the emulsion, thereby preventing the occurrence of emulsion or reducing the generated emulsion. Estimate that it will be possible.
Also, as described above, an emulsion treatment agent having a low HLB value such as HLB of 10 or less, preferably 8 or less is suitable from the viewpoint of being easily adsorbed on the surface of hydrophobic pigment particles.

The nonionic surfactant preferably has a mass average molecular weight (Mw; hereinafter simply referred to as “average molecular weight”) of 1200 or more.
In the regeneration method of the present invention, after the emulsion treatment agent is added, it is separated into the regenerated cleaning liquid and the reclaimed water by the gravity sedimentation method, but the fine ink pigment is deposited on the surface of the regenerated water layer to separate the regenerated cleaning liquid and the ink pigment component. To do. If the pigment particles remain fine, it takes time to separate the cleaning liquid and the pigment by a method such as subsequent filtration.
However, the emulsion treatment agent mainly composed of a nonionic surfactant having an average molecular weight of 1200 or more is a flocculant that aggregates and coarsens the ink pigment component at the same time as preventing emulsion generation or reducing the emulsion volume. Experimentally found that there is a function.

In the case of an ionic surfactant, even if the molecular weight is smaller, the charge opposite to the charging characteristics of the pigment (the activator and its counter ion are present in a charged state, so the pigment particles are positive or negative) The active agent and its counter ion must be electrostatically attracted to the pigment particles, regardless of whether they are charged.) It is possible to agglomerate the pigment particles by eliminating the repulsion. However, since the emulsion treatment agent of the present invention is a nonionic surfactant, it cannot exhibit an aggregating effect due to neutralization of electrostatic repulsion.
In the aggregation of pigment fine particles by a nonionic surfactant, one nonionic surfactant molecule is adsorbed on a plurality of pigment fine particles, and these pigment particles are entangled to form aggregated particles. The molecular chain of the ionic surfactant needs to have a certain length. It has been experimentally found that an average molecular weight of 1200 or more is necessary to ensure the necessary length.
Due to the aggregation of the pigment fine particles by the nonionic surfactant, the filtration rate becomes 10 times faster than when the emulsion treatment agent is not added. The washing waste liquid from which the pigment particles have been removed by filtration is quickly separated in 10 to 15 minutes due to the difference in specific gravity between the organic detergent and water, and the regenerated washing liquid can be recovered as a transparent clean liquid.

  As such a nonionic surfactant, New Pole PE-61 (HLB 1.8-2.0, polyoxypropylene part) which is a polyoxyethylene-polyoxypropylene block copolymer of Sanyo Chemical Industries, Ltd. Average molecular weight 1,750), Newpol PE-62 (HLB 4.0-4.3, average molecular weight 1,750 of polyoxypropylene part), DSK NL which is polyoxyethylene lauryl ether of Daiichi Kogyo Seiyaku Co., Ltd. -15 (HLB 5.0, average molecular weight of polyoxyethylene part 2,900), DSK NL-30 (HLB 8.1, average molecular weight of polyoxyethylene part 5,800), polyoxyethylene oleyl cetyl ether Neugen ET-69 type (HLB 5.7, average molecule of polyoxyethylene moiety) 4,440), Neugen ET-89 type (HLB 7.9, average molecular weight 7,170 of polyoxyethylene part), polyalkylene polyamine / propylene oxide / ethylene oxide adduct 206 (HLB 6.0, Average molecular weight 93,000), polyoxyethylene lauryl ether Neugen ET-83 (HLB 6.4, polyoxyethylene part average molecular weight 3,870), polyoxyethylene polyoxypropylene block polymer Epan 410 (HLB 6.0, molecular weight of hydrophobic group 1,200..., The molecular weight of the active agent is obtained by adding the molecular weight of the hydrophilic group), but is not limited thereto.

In the emulsion treatment agent addition step, the emulsion treatment agent is added to the waste liquid so that the active ingredient of the emulsion treatment agent is 0.05% by mass or more and 5% by mass with respect to the whole waste liquid by the separation step. It is preferable to set it as the process to carry out.
When the emulsion treatment agent of the present invention is added to the waste liquid and stirred and then allowed to stand, the bulky sludge is reduced, the upper part is the washing liquid layer, and the middle part is the sludge layer (the ink pigment component is contained in this sludge layer). When the effect of the emulsion treating agent is sufficient, the sludge layer disappears and becomes a layer of ink pigment fine particles) The lower part is separated into three layers of an aqueous layer, but the above three components (organic cleaning liquid, ink pigment) , And water) have a correlation with the emulsion treatment agent concentration. Basically, the higher the addition concentration, the shorter the treatment time. Although there are some differences depending on the waste liquid, the addition amount of the emulsion treatment agent needs to be at least 0.05% by mass in order to obtain a sufficient sludge reduction effect.
On the other hand, when the addition amount of the emulsion treatment agent exceeds 5% by mass, the treatment agent is re-emulsified in the aqueous layer by the emulsion treatment agent itself when the treatment cost of the emulsion treatment agent is increased and the washing waste liquid is vigorously stirred. In some cases, it is not preferable.

In addition, since the emulsion treating agent of the present invention has a low HLB, it is soluble in an organic solvent and is also dissolved in the regenerated cleaning liquid, so that the waste liquid after blanket cleaning is performed using the regenerated cleaning liquid. Needless to say, at the time of regeneration, it is not necessary to newly add 0.05 mass% to 5 mass% of the emulsion treatment agent to the waste liquid. In such a case, the deficiency may be replenished when the concentration falls below the appropriate concentration range in the previous period.
As the concentration control method in the waste liquid of the emulsion treatment agent, a method of monitoring the concentration of the emulsion treatment agent in the waste liquid before the regeneration treatment or in the regenerated cleaning liquid after the regeneration, and replenishing when it is likely to be below the optimum concentration range is preferable. . Examples of the concentration monitoring method include, but are not limited to, a method in which chemical analysis is performed at regular time intervals, and a method in which the electrical conductivity of the regenerated cleaning liquid is measured for a certain time or continuously.
The simplest concentration control method is to use a blanket cleaning solution with an emulsion treatment agent added to the optimum concentration range from the beginning, and when replenishing the blanket cleaning solution, add the emulsion treatment agent to the optimum concentration range. What is necessary is just to replenish the blanket washing liquid which was made.

As an addition method of the emulsion treatment liquid of the present invention, an emulsion treatment agent may be added to the waste liquid, and then stirred appropriately, and left in a gravity sedimentation type waste liquid regeneration container of a waste liquid treatment apparatus for separation treatment. That is, the above-mentioned waste liquid recycling method for a printing press according to the present invention includes a storage step of storing the waste liquid in a storage container until the waste liquid discharged from the printing press is put into the recycling apparatus. It is good also as performing the said emulsion process agent addition process, stirring the liquid containing the said waste liquid and the said emulsion process agent, and performing the said isolation | separation process in the said reproducing | regenerating apparatus after the said storage process. Alternatively, the waste liquid recycling method for a printing press according to the present invention includes a storage step of storing the waste liquid in a storage container until the waste liquid discharged from the printing press is put into the recycling apparatus, and the storage step And the separation step, the emulsion treatment agent is added to the waste liquid at some point in the waste liquid flow path provided between the storage container and the regeneration container, and the waste liquid and the emulsion treatment agent are added. It is good also as performing the said emulsion processing agent addition process by stirring the liquid containing this by an own flow.
Therefore, the emulsion treatment agent may be added to the waste liquid in the storage container that stores the waste liquid discharged from the printing press until it is put into the regenerator, and the gravity of the waste liquid regeneration container from the waste liquid storage container may be added. It may be added to the waste liquid somewhere in the waste liquid flow path between the sedimentation layers.

Or you may add the emulsion processing agent of this invention to the receiving tank of the washing | cleaning waste liquid discharged | emitted from a printing press. That is, in the waste liquid recycling method for a printing press according to the present invention, the emulsion treatment agent adding step may be a step of adding the emulsion treatment agent to a waste liquid receiving tank that receives the waste liquid discharged from the printing press.
The waste liquid receiving tank may be a waste liquid receiving tank provided for each printing unit, or may be a waste liquid receiving tank that collects and receives cleaning waste liquid discharged from each printing unit. Furthermore, the cleaning waste liquid in the waste liquid receiving tank may be agitated strongly, and conversely there is almost no agitation (refers to the degree of fluid flow caused by the liquid flowing into the tank). It ’s okay.

  The waste liquid regenerating apparatus of the present invention is a waste liquid regenerating apparatus for regenerating a waste liquid containing an ink pigment, an organic cleaning agent, and water, and the waste liquid is retained for a certain period of time to regenerate the cleaning liquid, ink pigment, And a regeneration container that is separated into water, a regeneration liquid storage container that is provided adjacent to the regeneration container and collects the regeneration cleaning liquid separated in the regeneration container, and that is disposed adjacent to the regeneration container, the regeneration container A recovered water storage container for recovering the reclaimed water separated in the container, a filter provided below the regenerator, and provided with an ink pigment recovery filter therein, and the filtrate from the filter is regenerated and washed by gravity sedimentation. And a filtrate separation container that separates into water.

  If this waste liquid recycling apparatus is used, a waste liquid recycling method for a printing press can be performed by a batch system or a continuous system. In a waste liquid regeneration method for regenerating a waste liquid containing an ink pigment, an organic cleaning agent, and water by a batch method, a step of charging the waste liquid into the waste liquid regeneration apparatus, and a regeneration cleaning liquid for regenerating the waste liquid using the waste liquid regeneration apparatus, The process of separating into ink pigment and water is performed in a batch mode.

  In a waste liquid regeneration method for regenerating a waste liquid containing an ink pigment, an organic cleaning agent, and water by a continuous method, a step of supplying the waste liquid to the waste liquid regenerator, and a regeneration cleaning liquid for regenerating the waste liquid using the waste liquid regenerator, The step of separating the ink pigment and water is performed simultaneously in a continuous manner.

  According to the present invention, it is possible to easily separate a cleaning waste liquid of a printing press in which three components of an ink pigment, an organic cleaning liquid, and water are mixed with a single device. That is, when the cleaning waste liquid containing the above three components is vigorously stirred by adding to the cleaning waste liquid a substance having at least a function of breaking the emulsion and aggregating the ink pigment (hereinafter referred to as an emulsion treatment agent). In order to prevent the generation of a bulky sludge substance in which an emulsion mainly composed of a cleaning liquid component and water is aggregated, or to reduce the volume of the bulky sludge generated to 1/5 or less, preferably 1/10 or less, Regardless of the agitation state of the waste liquid, it is possible to quickly and efficiently separate the three components of the ink pigment layer at the interface between the cleaning liquid and water with the upper part being the washing liquid layer and the lower part being the water layer by the gravity settling method.

  Furthermore, the present invention also applies to the case where filtration is performed in order to remove the pigment from the waste liquid separated as the three components of the ink pigment layer at the interface between the cleaning liquid and the water, with the upper part being the cleaning liquid layer and the lower part being the water layer by leaving the cleaning waste liquid of the printing press By adding this emulsion treatment agent to the washing waste liquid, the ink pigment particles present in the fine particle state are aggregated and coarsened, and filtration becomes extremely easy, so that the treatment speed can be improved.

Hereinafter, embodiments of the present invention will be described with reference to the drawings and examples.
[Waste liquid recycling equipment]
FIG. 1 shows a waste liquid regenerating apparatus according to the present invention, and FIG. 1 is a schematic cross-sectional view of the waste liquid regenerating apparatus as viewed from the side.
As shown in FIG. 1, the waste liquid regeneration apparatus 1 includes a waste liquid regeneration container 5 that retains the waste liquid for a certain period of time and separates the waste liquid into a regenerated cleaning liquid 3 and water 2 by gravity sedimentation, and the waste liquid regeneration container 5 separates the waste liquid in the waste liquid regeneration container 5. The regenerated cleaning liquid storage container 6 for recovering the regenerated liquid that is the regenerated cleaning liquid, the recovered water storage container 7 for recovering the reclaimed water separated in the waste liquid regenerating container, and disposed below the waste liquid regenerating container, A filtration tank (filter and filtrate separation container) 9 provided with an ink pigment recovery filter 8 is provided.

First, the case where the waste liquid recycling apparatus 1 of the present invention is used in a batch system will be described.
An opening / closing valve 11 provided at the side of the waste liquid regeneration container 5 for opening and closing the flow path between the waste liquid regeneration container 5 and the recovered water storage container 7 adjacent thereto, and provided at the bottom of the waste liquid regeneration container 5 After closing the on-off valve 12 and opening the on-off valve 14 provided in the waste liquid input pipe 13 for introducing the waste liquid into the waste liquid regeneration container 5, the cleaning waste liquid 15 to which the emulsion treating agent has been added is recycled from the waste liquid input pipe 13. Feed into container 5. The cleaning waste liquid 15 overflows the wall 16 between the waste liquid regeneration container 5 and the regeneration liquid storage container 6 and flows into the regeneration liquid storage container 6 and the recovered water storage container 7 adjacent to the waste liquid regeneration container 5. The liquid feeding is stopped and the on-off valve 14 provided in the waste liquid input pipe 13 is closed.
Thereafter, the cleaning waste liquid 15 is allowed to stand in the waste liquid regeneration container 5, whereby the cleaning waste liquid 15 is separated into the regeneration cleaning liquid 3, the ink pigment 4, and the water 2. FIG. 1 shows a state in which the regenerated cleaning liquid 3, the ink pigment 4, and the water 2 are separated.

  Since the time required for the separation correlates with the addition amount of the emulsion treatment agent, when it is desired to shorten the treatment time, the addition amount of the emulsion treatment agent may be increased within the range of the appropriate addition amount. As a rough guide, even if there is a sludge-like substance, it can often be separated by adding it to a concentration of 0.2% by mass of the emulsion treatment agent relative to the waste liquid and allowing it to stand for several hours. However, since there are differences depending on the types of cleaning liquid and ink, the amount of the emulsion treatment agent to be added may be determined in relation to the processing time in each case. Needless to say, if the emulsion treatment agent is not added, if there is a sludge-like substance, the waste liquid cannot be separated even if it is left standing overnight in the waste liquid regeneration container 5.

  When the regenerated cleaning liquid 3, the ink pigment 4, and the water 2 are separated, the on-off valve 12 provided at the bottom of the waste liquid regeneration container 5 is opened, and the separated waste liquid is poured into the filtration tank 9. At this time, in order to avoid the separated three components from being mixed again, it is preferable to avoid flushing away. The waste liquid that has been washed away in a separated state is filtered by a filter 8 provided in the filtration tank 9. Since the ink pigment 4 is a bulky aggregate 18 due to the pigment aggregation action of the emulsion treatment agent, the aggregate 18 of the ink pigment 4 is filtered on the filter 8 without clogging the filter 8 in the filtration tank 9. Then, the water 2 and the regenerated cleaning liquid 3 are quickly filtered out and stored in the filtration tank 9.

  After the filtration, when the interface between the water stored in the filtration tank 9 and the regenerated cleaning liquid is stabilized, the on-off valve 21 for opening and closing the extraction pipe 20 connected to the lower part of the filtration tank 9 is opened, and a part of the side wall of the filtration tank 9 is opened. The water stored in the filtration tank 9 is extracted from the extraction pipe 20 while confirming the position of the interface from the transparent observation window 22 constituting the structure. When the interface approaches the on-off valve 21 of the extraction pipe 20 and the regenerated cleaning liquid reaches the extraction pipe 20, the on-off valve 21 is closed. The water extracted and recovered from the extraction pipe 20 may be disposed of after appropriate processing if necessary.

Next, the on-off valve 21 of the extraction pipe 20 is opened, and the regenerated cleaning liquid coming out of the extraction pipe 20 is transferred to an appropriate container (not shown). The regenerated cleaning liquid transferred to the container may be reused for cleaning the printing press.
The filtration operation as described above is repeated several times, and when the filtration speed of the filter 8 becomes slow, the filter 8 is removed from the filtration tank 9 and replaced with a new filter 8 or ink accumulated on the filter 8. After removing the pigment, a countermeasure such as attaching the filter 8 to the filtration tank 9 again may be taken.
When the above operation is completed, the same operation is repeated again, and the regeneration process of the cleaning waste liquid 15 may be repeated in a batch manner.

Next, the case where the waste liquid recycling apparatus 1 of the present invention is used in a continuous manner will be described.
The on-off valve 12 provided at the bottom of the waste liquid regeneration container 5 and the on-off valve 14 provided on the waste liquid input pipe 13 are closed to open and close the flow path between the waste liquid regeneration container 5 and the recovered water storage container 7. An on-off valve 11 provided on the side of the regeneration container 5, an on-off valve 26 for opening / closing the regeneration cleaning liquid outflow pipe 25 connected to the lower part of the regeneration cleaning liquid storage container 6, and a side of the recovered water storage container 7. The on-off valve 29 that opens and closes the recovered water outflow pipe 28 is opened. Next, the water is stored in the waste liquid recycling container 5 until some water flows out from the inlet of the recovered water outflow pipe 28. The water may be put from above by removing the lid 30 on the upper part of the waste liquid regeneration container 5.

Next, a cleaning liquid layer is formed on the water. That is, the cleaning solution is gently poured into the waste solution regeneration container 5 so that the wall 16 between the waste solution regeneration container 5 and the regeneration solution storage container 6 does not mix with the previously introduced water until the cleaning solution slightly overflows. This cleaning agent may be new or may be a regenerated cleaning agent.
Thereafter, the on-off valve 14 provided in the waste liquid input pipe 13 is opened, and the cleaning waste liquid 15 to which the emulsion treating agent is added is gradually fed into the waste liquid regeneration container 5 from the waste liquid input pipe 1313. At this time, the feeding speed of the cleaning waste liquid 15 is such that the cleaning waste liquid 15 has a residence time required for separating the cleaning waste liquid 15 into the three components of the regenerating cleaning liquid 3, the ink pigment 4, and the water 2 inside the waste liquid regeneration container 5. Need to be speed. While staying in the waste liquid regeneration container 5, the cleaning waste liquid 15 is separated into the regenerated cleaning liquid 3, the ink pigment 4, and the water 2. The regenerated cleaning liquid 3 overflows the wall 16 between the waste liquid regenerating container 5 and the regenerated cleaning liquid storage container 6 and flows into the regenerated cleaning liquid storage solution 6. On the other hand, the water 2 passes through the on-off valve 11 provided on the side of the waste liquid regeneration container 5 and flows into the recovered water storage container 7.

  When regenerating the cleaning waste liquid 15 in a continuous manner, the on-off valves 26 and 28 of the regenerated cleaning liquid outflow pipe 25 and the recovered water outflow pipe 28 are opened, and the regenerated cleaning liquid storage container 6 and the recovered water storage container 7 are respectively opened. The recovered regenerated cleaning liquid and water may be allowed to flow into storage containers (not shown) in which they are stored. The regenerated cleaning liquid may be reused again as a cleaning liquid for the printing press. The recovered water may be disposed of after appropriate treatment if necessary.

  Here, since the time required for separation, that is, the necessary residence time correlates with the amount of emulsion treatment agent added, when it is desired to shorten the treatment time, the addition amount of the emulsion treatment agent should be increased within the range of the appropriate addition amount. Good. As a rough guideline, when the capacity of the waste liquid recycling container 5 is 20 liters, even if there is a sludge-like substance, if the emulsion treatment agent concentration is 0.2 mass% with respect to the waste liquid, the waste liquid feed rate is 2.5 liters / hour. In many cases, the treatment can be performed with a residence time of 8 hours. However, since there is a difference depending on the type of cleaning liquid and ink, the relationship with the treatment time may be confirmed in each case. Needless to say, if the emulsion treatment agent is not added, if there is a sludge substance, the waste liquid cannot be treated even if the residence time is 24 hours in the waste liquid regeneration container.

As the cleaning waste liquid 15 is regenerated, the ink pigment 4 is accumulated at the interface between the regenerated cleaning liquid 3 and the water 2 inside the waste liquid regeneration container 5. Therefore, when the ink pigment 4 is accumulated to some extent, the cleaning waste liquid 15 is accumulated. It is necessary to interrupt the regeneration process once and discharge the ink pigment 4. This ink pigment discharge operation will be described below.
After closing the on-off valve 11 provided on the side of the waste liquid regeneration container 5 and 14 provided on the waste liquid input pipe 13, the on-off valve 12 provided on the bottom of the waste liquid regeneration container 5 is opened, and the inside of the waste liquid regeneration container 5 is opened. The regenerated cleaning liquid 3, the ink pigment 4 and the water 2 remaining in the water are poured into the filtration tank 9. At this time, in order to avoid the separated three components from being mixed again, it is preferable to avoid flushing away. The regenerated cleaning liquid 3, the ink pigment 4, and the water 2 that have been washed away are filtered by a filter 8 provided in the filtration tank 9. Since the ink pigment 4 is a bulky aggregate 18 due to the pigment aggregation action of the emulsion treatment agent, the aggregate 18 of the ink pigment 4 is filtered on the filter 8 without clogging the filter 8 in the filtration tank 9. Then, the water 2 and the regenerated cleaning liquid 3 are quickly filtered out and stored in the filtration tank 9.

After the filtration, when the interface between the water stored in the filtration tank 9 and the regenerated cleaning liquid is stabilized, the on-off valve 21 for opening and closing the extraction pipe 20 connected to the lower part of the filtration tank 9 is opened, and a part of the side wall of the filtration tank 9 is opened. The water stored in the filtration tank 9 is extracted from the extraction pipe 20 while confirming the position of the interface from the transparent observation window 22 constituting the structure. When the interface approaches the on-off valve 21 of the extraction pipe 20 and the regenerated cleaning liquid reaches the extraction pipe 20, the on-off valve 21 is closed. The water extracted and recovered from the extraction pipe 20 may be disposed of after being appropriately treated as necessary.
Next, the on-off valve 21 of the extraction pipe 20 is opened, and the regenerated cleaning liquid coming out of the extraction pipe 20 is transferred to an appropriate container (not shown). The regenerated cleaning liquid transferred to the container may be reused for cleaning the printing press together with the regenerated cleaning liquid recovered from the regenerated cleaning liquid outflow pipe 25.

The filtration operation as described above is repeated several times, and when the filtration speed of the filter 8 becomes slow, the filter 8 is removed from the filtration tank 9 and replaced with a new filter 8 or ink accumulated on the filter 8. After removing the pigment, a countermeasure such as attaching the filter 8 to the filtration tank 9 again may be taken.
When the above operation is completed, the same operation is repeated again, and the regeneration process of the cleaning waste liquid 15 may be repeated in a continuous manner.

[Washing waste liquid (simulated waste liquid)]
The following ink, cleaning liquid, and water were mixed to prepare a simulated waste liquid, and a waste liquid regeneration test was performed.
(ink)
1) High Echo MZ (Toyo Ink Manufacturing Co., Ltd.)
2) Geosu GN (Dainippon Ink Chemical Co., Ltd.)
3) Super Tech Plus H (manufactured by T & K Toka)
4) Diatone M (manufactured by Sakata Inx Corporation)
5) Celvo Y (manufactured by Tokyo Ink Co., Ltd.)

(Cleaning solution)
1) Die Clean (Dainippon Ink Chemical Co., Ltd.)
2) Auto Clean (Nikken Chemical Co., Ltd.)
3) Bracrine S (made by Nikka Corporation)
4) Print cleaner (Toyo Ink Manufacturing Co., Ltd.)
5) Super Clean (made by The Ink Tech Co., Ltd.)

[Example 1]
High-echo MZ indigo, red, yellow, and black inks are mixed evenly, diluted with dye clean to a pigment concentration of 2% by mass, and then added with the same amount of water as the washing liquid in which the pigment is dispersed. 20 kg of waste liquid was prepared. The simulated waste liquid was stirred for 15 minutes with a homogenizer (trade name ULTRA TURRAX Disperser T-50, manufactured by MASUDA) and allowed to stand for 10 minutes. However, the simulated waste liquid was estimated to be an emulsion composed of a cleaning liquid and water (fluidity). In particular, the lower part is in the form of an elastic jelly, which is hereinafter referred to as “sludge substance”), and the cleaning liquid layer and the water layer could not be visually confirmed. The simulated waste liquid in this state is referred to as simulated waste liquid 201. FIG. 2 shows a configuration diagram of the simulated waste liquid 201.
New emulsion PE-61 ((HLB 1.8-2.0, polyoxypropylene part average molecular weight 1,750, manufactured by Sanyo Chemical Co., Ltd.) as an emulsion treatment agent was added to this simulated waste liquid 201 to 0.05. It added so that it might become mass%.

The simulated waste liquid 211 (20 liters) to which the emulsion treating agent was added was fed from the waste liquid input pipe 13 into the waste liquid regeneration container 5 of the waste liquid regeneration apparatus 1 by a pump at a liquid feed speed of 4 liters / hour. Before the simulated waste liquid 211 overflows the wall 16 between the waste liquid regeneration container 5 and the regenerated liquid storage container 6, the simulated waste liquid 211 is stopped from being fed, and the on-off valve 14 provided in the waste liquid input pipe 13 is closed. The simulated waste liquid 211 was left in the waste liquid regeneration container 5 for 8 hours. FIG. 3 is a schematic diagram showing the state of the simulated waste liquid 221 that has been added with the emulsion treating agent and left to stand for 8 hours after stirring.
The simulated waste liquid 221 after standing for 8 hours was slowly dropped into the filtration tank 9 with the on-off valve 12 provided at the bottom of the waste liquid regeneration container 5 being half-opened, and 20 liters of liquid was filtered in about 5 minutes.

  The inside of the filtration tank 9 was observed from the observation window 22, and the opening / closing valve 21 of the extraction pipe 20 was opened because the interface between the recovered water and the regenerated cleaning liquid in the filtration tank 9 was stabilized 15 minutes after the filtration. The recovered water was extracted from the extraction pipe 20 while confirming the position of the interface from the observation window 22 provided in the waste liquid regeneration container 5. When the interface approached the open / close valve 21 of the extraction pipe 20 and the regenerated cleaning liquid reached the extraction pipe 20, the open / close valve 21 was closed. The recovered water was received in a storage container for recovered water, treated with waste water so as to meet the reference values of biological oxygen demand (BOD) and chemical oxygen demand (COD) as necessary, and then discarded.

Next, the on-off valve 21 of the extraction pipe 20 was opened, and the regenerated cleaning liquid coming out of the extraction pipe 20 was received in the regenerated cleaning liquid storage container and reused for cleaning the printing press.
The simulated waste liquid as described above was repeatedly treated 5 times. Since the filtration time in the fifth regeneration process required about twice as long as the filtration time in the first regeneration process, the filter 8 was removed from the filtration tank 9 and replaced with a new filter 8.
Thus, the regenerated washing liquid recovered by the five regenerating processes was about 47 liters, the regenerated water was about 48 liters, and the ink pigment (wet state including the liquid) was about 0.35 kg.

According to the treatment method of this example, by adding an emulsion treatment agent to a washing waste liquid containing a bulky sludge-like substance that cannot be regenerated only by gravity sedimentation and filtration operation, it is possible to perform gravity sedimentation and filtration operation by a batch method. It can be separated into cleaning liquid, ink pigment, and recovered water, and can be recycled. That is, in the treatment method of the present embodiment, it is possible to shorten the time for separating the cleaning waste liquid containing the bulky sludge substance into the organic cleaning liquid, the ink pigment, and water, and the cleaning liquid finally separated is reused. Since the volume of the ink pigment to be discarded is reduced, the running cost of the printing press including the disposal cost can be reduced.
In addition, the treatment method of this example is an environment-friendly treatment method because energy such as electric power is not used for separation of the cleaning waste liquid except that an emulsion treatment agent is added.

[Comparative Example 1] No addition of emulsion treatment agent In Example 1, the simulation waste solution 201 was treated in the same manner except that New Pole PE-61 (manufactured by Sanyo Chemical) was not added to the simulation waste solution 201 as an emulsion treatment agent. did.
After 8 hours of standing, the on-off valve 12 provided at the bottom of the waste liquid regeneration container 5 was opened half way, and the waste liquid was slowly poured into the filtration tank 9. About 1 liter of filtrate (total of regenerated cleaning agent and recovered water) collected in the tank in about 1 minute at the beginning, but after that, the filter 8 was clogged and the filtrate was about 2 liters even after 8 hours. 20 liters of waste liquid could not be filtered in 8 hours.

[Example 2]
0.2% of New Pole PE-61 ((HLB 1.8-2.0, average molecular weight of polyoxypropylene part 1,750, manufactured by Sanyo Chemical Co., Ltd.)) as an emulsion treatment agent for the same simulated waste liquid 201 as in Example 1. The liquid added with mass% was designated as simulated waste liquid 211.
After closing the on-off valves 12 and 14 provided at the bottom of the waste liquid regeneration container 5 and opening the on-off valves 11 and 26 and 29, the lid 30 on the upper part of the waste liquid regeneration container 5 is removed and the recovery water outflow pipe 28 is opened. The water was stored in the waste liquid recycling container 5 until some water flowed out.
Next, gently pour the new cleaning liquid into the waste liquid regeneration container 5 so that the cleaning liquid slightly overflows the wall 16 between the waste liquid regeneration container 5 and the regeneration liquid storage container 6 so as not to mix with the previously added water. It is.

Thereafter, the on-off valve 14 was opened and 50 liters of the simulated waste liquid 211 added with the emulsion treatment agent from the waste liquid input pipe 13 was continuously fed into the waste liquid regeneration container 5 at a liquid feeding speed of 2.5 liters / hour. . The simulated waste liquid 211 sent into the waste liquid regeneration container 5 was separated into a regenerated cleaning liquid, an ink pigment, and water while staying in the waste liquid regeneration container 5.
The regenerated cleaning liquid overflowed the wall 16 between the waste liquid regenerating container 5 and the regenerated cleaning liquid storage container 6 to flow into the regenerated cleaning liquid storage solution 6, and was further discharged from the regenerated cleaning liquid outflow pipe 25 and stored in the regenerated cleaning liquid storage container. The amount of the cleaning solution that could be regenerated was about 24 liters.

On the other hand, the water passed through the on-off valve 11 on the side of the waste liquid regeneration container 5 and flowed into the recovered water storage container 7, and was further discharged from the recovered water outflow pipe 28 and received in the recovered water storage container. The recovered water was approximately 24.5 liters, and was drained after confirming by analysis that the water quality could be discharged into sewage.
Although the ink pigment remained in the waste liquid recycling container 5, it was possible to continue the treatment of the simulated waste liquid 211. However, in order to confirm the amount of the remaining ink pigment, the ink pigment was discharged by the following procedure.
After closing the on-off valve 11 on the side of the waste liquid regeneration container 5 and the on-off valve 14 of the waste liquid input pipe 13, the on-off valve 12 on the bottom of the waste liquid regeneration container 5 is opened halfway to regenerate the cleaning liquid remaining in the waste liquid regeneration container 5, The ink pigment and water were slowly poured into the filtration tank 9 and filtered.

The inside of the filtration tank 9 was observed through the observation window 22, and the interface between the recovered water and the regenerated cleaning liquid in the filtration tank 9 was stabilized 15 minutes after the completion of filtration, and therefore the opening / closing valve 21 of the extraction pipe 20 was opened. The recovered water was extracted from the extraction pipe 20 while confirming the position of the interface from the observation window 22 provided in the waste liquid regeneration container 5. When the interface approached the open / close valve 21 of the extraction pipe 20 and the regenerated cleaning liquid reached the extraction pipe 20, the open / close valve 21 was closed. The recovered water was received in a storage container for recovered water and drained in the same manner as described above.
Next, the on-off valve 21 of the extraction pipe 20 was opened, and the regenerated cleaning liquid coming out of the extraction pipe 20 was received in the regenerated cleaning liquid storage container and reused for cleaning the printing press.
Thereafter, the filter 8 was removed from the filtration tank 9, and the weight of the wet ink pigment was measured and found to be about 0.18 kg. A new filter 8 was attached to the filtration tank 9.

According to the processing method of this example, an emulsion treatment agent is added to a cleaning waste liquid containing a bulky sludge-like substance that cannot be regenerated only by gravity sedimentation and filtration. Then, it can be separated into recovered water, and the cleaning liquid can be regenerated. That is, in the processing method of this example, the cleaning waste liquid containing the bulky sludge-like substance can be separated into the organic cleaning liquid, the ink pigment, and water continuously in a short time and finally separated. Since the cleaning liquid can be reused and the volume of the ink pigment to be discarded is reduced, the running cost of the printing press including the disposal cost can be reduced.
In addition, the treatment method of this example is an environment-friendly treatment method because energy such as electric power is not used for separation of the cleaning waste liquid except that an emulsion treatment agent is added.

[Comparative Example 2] No addition of emulsion treatment agent In Example 2, the simulation waste solution 201 was treated in the same manner except that New Pole PE-61 (manufactured by Sanyo Chemical) was not added as an emulsion treatment agent to the simulation waste solution 201. did.
The on-off valve 14 was opened, and the simulated waste liquid 201 to which the emulsion treatment agent was not added was continuously fed from the waste liquid charging pipe 13 into the waste liquid regeneration container 5 at a liquid feeding speed of 2.5 liters / hour. About 4 hours after the start of liquid feeding, since the cleaning waste liquid (simulated waste liquid 201) itself flowed out from the regenerated cleaning liquid outflow pipe 25 from which the transparent regenerated cleaning liquid should flow out originally, the liquid feeding was stopped at that time. When the lid 30 of the waste liquid regeneration container 5 is removed and the inside of the waste liquid regeneration container 5 is observed, it is confirmed that the inside of the waste liquid regeneration container is filled with sludge-like substances and that it cannot be separated into cleaning liquid, ink pigment, and water at all. did.

It is a schematic cross section showing an example of a waste liquid recycling apparatus. It is a schematic diagram which shows the state which does not add an emulsion processing agent of the simulation waste liquid regenerated by the Example and the comparative example. It is a schematic diagram which shows the state which added the emulsion processing agent to the simulation waste liquid regenerated in the Example, and left still for 8 hours after stirring. It is a figure which shows schematic structure of the conventional waste-liquid reproduction | regeneration apparatus used with a sedimentation method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Waste liquid regeneration apparatus 2 Water 3 Recycled cleaning liquid 4 Ink pigment 5 Waste liquid regeneration container 6 Recycled cleaning liquid storage container 7 Recovered water storage container 8 Ink pigment recovery filter 9 Filtration tank 11 On-off valve 12 On-off valve 13 Waste liquid input pipe 14 On-off valve 15 Washing waste liquid 16 Wall 18 Aggregate of ink pigment 20 Extraction pipe 21 On-off valve 22 Viewing window 25 Recycled washing liquid outflow pipe 26 On-off valve 28 Collected water outflow pipe 29 On-off valve 30 Lid

Claims (12)

A waste liquid recycling method in which a waste liquid containing an ink pigment, an organic cleaning liquid, and water is put into a regeneration device having a regeneration container to regenerate,
A separation step of separating the waste liquid in the regeneration container into a regenerated cleaning liquid, an ink pigment, and water using gravity sedimentation;
A waste liquid for a printing press, characterized by having an emulsion treatment agent addition step for adding an emulsion treatment agent that breaks an emulsion mainly composed of water and a washing liquid and agglomerates ink pigment particles to the waste solution before the separation step. Playback method.   The method for regenerating a waste liquid of a printing press according to claim 1, wherein the emulsion treatment agent contains a nonionic surfactant as a main component.   The waste liquid recycling method for a printing press according to claim 2, wherein the nonionic surfactant is a copolymer having a polyoxyethylene chain as a part of the structure, and the HLB is 10 or less. .   The waste liquid recycling method for a printing press according to claim 2, wherein the nonionic surfactant is a copolymer having a polyoxyethylene chain as a part of the structure, and the HLB is 8 or less. .   The method for reclaiming waste liquid from a printing press according to any one of claims 2 to 4, wherein the nonionic surfactant has a mass average molecular weight of 1200 or more.   In the emulsion treatment agent addition step, the emulsion treatment agent is added to the waste liquid so that the active ingredient of the emulsion treatment agent is 0.05% by mass or more and 5% by mass with respect to the whole waste liquid by the separation step. The method for recycling waste liquid of a printing press according to any one of claims 1 to 5, wherein A storage step of storing the waste liquid in a storage container until the waste liquid discharged from the printing press is put into the regenerator;
In the storage step, the emulsion treatment agent addition step is performed, and the liquid containing the waste liquid and the emulsion treatment agent is stirred,
The waste liquid regeneration method for a printing press according to any one of claims 1 to 6, wherein the separation step is performed in the regeneration device after the storage step. A storage step of storing the waste liquid in a storage container until the waste liquid discharged from the printing press is put into the regenerator;
Between the storage step and the separation step, the emulsion treatment agent is added to the waste liquid somewhere in the waste liquid flow path provided between the storage container and the regeneration container, and the waste liquid and the The waste liquid regeneration method for a printing press according to any one of claims 1 to 6, wherein the emulsion treatment agent addition step is performed by stirring the liquid containing the emulsion treatment agent in its own flow.   The said emulsion processing agent addition process is a process of adding the said emulsion processing agent to the waste liquid receiving tank which receives the waste liquid discharged | emitted from a printing machine, The any one of Claims 1-6 characterized by the above-mentioned. Method for recycling waste liquids in Japanese printing presses. A waste liquid regenerating apparatus for regenerating a waste liquid containing an ink pigment, an organic cleaning agent, and water,
A regeneration container that retains the waste liquid for a certain period of time and separates the waste liquid into a regenerated cleaning liquid, an ink pigment, and water by gravity sedimentation;
A regenerative liquid storage container that is provided adjacent to the regenerative container and collects the regenerated cleaning liquid separated in the regenerative container;
A recovered water storage container that is provided adjacent to the regeneration container and collects the recycled water separated in the regeneration container;
A filter provided below the regeneration container and having an ink pigment recovery filter therein;
A waste liquid recycling apparatus for a printing press, comprising: a filtrate separation container for separating a filtrate from the filter into a regenerated washing liquid and water by gravity sedimentation. A waste liquid regeneration method for regenerating a waste liquid containing an ink pigment, an organic cleaning agent, and water,
Charging the waste liquid into the waste liquid recycling apparatus according to claim 10;
A waste liquid recycling method for a printing press, characterized in that the step of separating the waste liquid into a recycled cleaning liquid, an ink pigment, and water using the waste liquid recycling apparatus is performed in a batch system. A waste liquid regeneration method for regenerating a waste liquid containing an ink pigment, an organic cleaning agent, and water,
Supplying the waste liquid to the waste liquid recycling apparatus according to claim 10;
A method of recycling a waste liquid of a printing press, wherein the step of separating the waste liquid into a regenerated cleaning liquid, an ink pigment, and water using the waste liquid recycling apparatus is simultaneously performed in a continuous manner.

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