JP7456027B1 - Method and apparatus for recovering tetramethylammonium hydroxide from developer waste solution and removing nitrogen-containing compounds - Google Patents

Abstract

[Problem] To provide an operating method and apparatus for producing tetramethylammonium hydroxide of higher purity with reduced operating costs for back-end purification and electrodialysis, and for preventing the recovered tetramethylammonium ions from containing other nitrogen-containing compounds. [Solution] To provide a method for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds from a waste developer solution, the method comprising: a first adsorption step of adsorbing tetramethylammonium hydroxide and nitrogen-containing compounds in the waste developer solution with a first ion resin 321; a first control step of controlling the flow of the waste developer solution to a high pH value and a high flow rate through the first ion resin, thereby desorbing the nitrogen-containing compounds from the first ion resin; a second control step of stopping the flow of the waste developer solution after the nitrogen-containing compounds from the first ion resin are desorbed; and a third control step of regenerating the first ion resin to obtain a tetramethylammonium salt solution. [Selected Figure] FIG.

Description

The present invention relates to a method for recovering a developer waste solution, and more particularly to a method and apparatus for recovering tetramethylammonium hydroxide from the developer waste solution and removing nitrogen-containing compounds.

The component of alkaline developer is tetra-methyl-ammonium hydroxide (TMAH: hereinafter abbreviated as TMAH or tetramethylammonium hydroxide), and in order to save resources, manufacturers A recovery system for the developer can be used to recover tetramethylammonium hydroxide, reducing resource consumption and saving costs while solving environmental problems.

In addition to the tetramethylammonium ion (TMA+) produced by the reaction of the original developer components, the developer waste solution used in the early stages contained negative photoresist, mono/polyvalent metal ions (e.g., sodium, iron, and aluminum ions, etc.). ), inorganic anions, organic anions, surfactants, and suspended particles.

In Taiwan Patent Nos. I366076 and I462770, the present inventors have proposed a new method for recovering tetramethylammonium hydroxide (TMAH) from developer waste with high efficiency, mainly "photoresist removal". , ``deionization,'' ``regeneration,'' ``purification,'' ``electrodialysis,'' and ``concentration adjustment.'' Of these, ``dephotoresist'' refers to the step of controlling the content of photoresist components in the development waste solution. Whether or not to carry out this process can be determined depending on the situation. For example, if the amount of photoresist components in the developing waste solution applied to the integrated circuit manufacturing industry is small, it may be omitted.

In the "deionization" step, the tetramethylammonium ions in the developer waste are extracted using an ion exchange resin method, and the resin column is regenerated while adsorbing the developer waste using a stepwise regeneration method and equipment, and the tetramethylammonium ions are ionized. The tetramethylammonium ion solution obtained here is not included in most of the other impurities in the developer waste solution and can reduce the negative effects of subsequent purification and electrodialysis.

However, as the process of integrated circuits becomes smaller and smaller in response to consumer needs, the size of each component of these electronic devices will also inevitably become smaller, and advances in the field of micro-processing will lead to smaller devices. Therefore, the chemicals required for the process have to be constantly improved and adjusted, for example by adding other nitrogen-containing compounds to increase efficiency, but the well-known None of the waste liquid recovery steps, such as "dephotoresist", "deionization", "regeneration", "purification" and "electrodialysis", can effectively remove other nitrogen-containing compounds; As a result, the recovered tetramethylammonium hydroxide (TMAH) also contains impurities such as other nitrogen-containing compounds, and such impurities may impede the quality of subsequent electrodialysis.

In view of these issues, it is recommended that the recovered tetramethylammonium ions contain other nitrogen-containing compounds to reduce the operational costs of back-end purification and electrodialysis and to produce more pure tetramethylammonium hydroxide. The development of operating methods and devices that prevent this from occurring is expected and is the goal of engineers' efforts.

Therefore, one object of the present invention is to recover tetramethylammonium hydroxide in a developer waste solution, which includes a first adsorption step, a first control step, a second control step, and a third control step. An object of the present invention is to provide a method for removing nitrogen-containing compounds.

In the first adsorption step, the developer waste solution in the container is injected into the first ionic resin at a first flow rate, and the tetramethylammonium hydroxide and nitrogen-containing compounds in the developer waste solution are adsorbed by the first ionic resin. 1. Drain the filtrate.

In the first control step, when the pH of the first filtrate is equal to or higher than a first pH set value, the flow rate at which the waste developer is injected into the first ionic resin increases to a second flow rate, and Desorbs nitrogen-containing compounds.

In the second control step, when the electrical conductivity of the developing waste liquid is close to the electrical conductivity of the first filtrate, injection of the developing waste liquid into the first ionic resin is stopped.

In the third control step, an acidic solution is applied to the first ionic resin to desorb tetramethylammonium hydroxide in the first ionic resin, thereby obtaining a tetramethylammonium salt solution.

As another technical means of the present invention, in the first adsorption step, the first flow rate is 2BV/hr, and in the first control step, the second flow rate is 4BV/hr or more.

As still another technical means of the present invention, in the first control step, the first pH setting value is 7.

As a further technical means of the present invention, the method for removing nitrogen-containing compounds by recovering tetramethylammonium hydroxide in the developer waste solution further includes a second adsorption step after the first adsorption step, and the method further includes a second adsorption step after the first adsorption step; In the adsorption step, if the electrical conductivity of the developer waste solution is different from the electrical conductivity of the first filtrate, the first filtrate is injected into a second ionic resin to remove the tetramethylammonium hydroxide and the tetramethylammonium hydroxide in the first filtrate. The nitrogen-containing compounds are adsorbed and a second filtrate is discharged.

As another technical means of the present invention, the method for recovering tetramethylammonium hydroxide in the developer waste solution and removing nitrogen-containing compounds includes an ion exchange step after the second adsorption step, and an ion exchange step after the ion exchange step. and a subsequent resin regeneration step, and in the ion exchange step, if the pH of the second filtrate is equal to or higher than a second pH set value, stopping the injection of the first filtrate into the second ionic resin. , an alkaline solution is applied to the second ionic resin, and in the resin regeneration step, injection of the alkaline solution to the second ionic resin is stopped and an acidic solution is applied to the second ionic resin.

As yet another technical means of the present invention, in the ion exchange step, the second pH setting value is 7, and the concentration of the alkaline solution is 0.1% to 2%.

As a further technical means of the present invention, the method for recovering tetramethylammonium hydroxide in the developer waste solution and removing nitrogen-containing compounds includes a waste solution discharge step after the ion exchange step, a waste solution discharge step and the further comprising a waste liquid recovery step between the resin regeneration step, and in the waste liquid discharge step, if the electrical conductivity of the alkaline solution flowing out from the second ionic resin is less than an electrical conductivity setting value, the second filtrate is removed. In the waste liquid recovery step, if the electrical conductivity of the alkaline solution flowing out from the second ionic resin is equal to or higher than the electrical conductivity setting value, the alkaline solution flowing out from the second ionic resin is collected in the container. Return to

As another technical means of the present invention, in the waste liquid discharging step and the waste liquid collecting step, the electric conductivity setting value is 400 us/cm.

Another object of the present invention is to apply the method for recovering tetramethylammonium hydroxide in the developer waste solution and removing nitrogen-containing compounds, the method comprising: a circulation unit; and a first adsorption unit; An apparatus for recovering tetramethylammonium oxide and removing nitrogen-containing compounds is provided.

The circulation unit includes a container containing developer waste and a water pump module connected to the container.

The first adsorption unit includes a first ionic resin connected to the container, a first pH detection module provided at the outlet of the first ionic resin, and a first electricity adsorption module provided at the inlet of the first ionic resin. a conductivity detection module, a second electrical conductivity detection module provided at the outlet of the first ionic resin, a first regeneration module provided at the inlet of the first ionic resin, and an outlet of the first ionic resin. a first valve module provided in the first valve module.

The water pump module injects the developer waste into the first ionic resin, the first regeneration module injects an acidic solution into the first ionic resin, and the first valve module injects the acidic solution into the first ionic resin. Control is performed so that the liquid is discharged to the outside or returned to the container.

Another object of the present invention is to apply it to a method for recovering tetramethylammonium hydroxide in the developer waste solution and removing nitrogen-containing compounds, the method comprising a circulation unit, a first adsorption unit, and a second adsorption unit. Another apparatus is provided for removing nitrogen-containing compounds by recovering tetramethylammonium hydroxide contained in a developer waste solution.

The circulation unit includes a container containing developer waste and a water pump module connected to the container.

The first adsorption unit includes a first ionic resin provided at the outlet of the container, a first pH detection module provided at the outlet of the first ionic resin, and a first pH detection module provided at the inlet of the first ionic resin. 1 electrical conductivity detection module, a second electrical conductivity detection module provided at the outlet of the first ionic resin, a first regeneration module provided at the inlet of the first ionic resin, and the first ionic resin. a first valve module disposed at an outlet of the water pump module, the water pump module injecting the developer waste into the first ionic resin, and the first regeneration module injecting an acidic solution into the first ionic resin. .

The second adsorption unit includes: a second ionic resin provided between the outlet of the first ionic resin and the inlet of the container; a second pH detection module provided at the outlet of the second ionic resin; A third electrical conductivity detection module provided at the outlet of the second ionic resin, an alkaline solution supply module provided at the inlet of the second ionic resin, and a second regeneration module provided at the inlet of the second ionic resin. module, and a second valve module provided at the outlet of the second ionic resin.

The alkaline solution supply module injects an alkaline solution into the second ionic resin, the second regeneration module injects an acidic solution into the second ionic resin, and the first valve module injects an alkaline solution into the second ionic resin. The second valve module performs control such that the liquid discharged from the second ionic resin is discharged to the outside or the second ionic resin is injected into the container. control to return to.

The beneficial effects of the present invention are as follows. In the first adsorption step, as tetramethylammonium hydroxide and nitrogen-containing compounds in the developer waste solution are adsorbed to the first ionic resin, the pH of the first filtrate increases due to an increase in the degree of saturation of the first ionic resin. If the pH of the first filtrate is higher than the first pH set value because the dissociation constant of the nitrogen-containing compound is much smaller than that of tetramethylammonium hydroxide, the dissociation constant of the nitrogen-containing compound is much smaller than that of tetramethylammonium hydroxide. Methyl ammonium undergoes ion exchange with the nitrogen-containing compound in the first ionic resin to separate the nitrogen-containing compound in the first ionic resin, thereby removing the nitrogen-containing compound in the first ionic resin. to achieve the purpose of reducing and improving the content of tetramethylammonium hydroxide in the first ionic resin, and to ensure the reduction of nitrogen-containing compounds in the tetramethylammonium salt solution discharged and collected in the third control step. However, the burden on subsequent processes is further reduced without affecting the total amount of tetramethylammonium hydroxide in the tetramethylammonium salt solution discharged and collected during regeneration of the first ionic resin with an acidic solution.

1 is a schematic view of a first preferred embodiment of an apparatus for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds from a developer waste solution according to the present invention. 3 is a flowchart showing the flow of the method in the first preferred embodiment. 2 is a diagram illustrating an apparatus in a second preferred embodiment of the invention. 3 is a flowchart showing the flow of the method in the second preferred embodiment.

The features and technical content of the related patent applications of the present invention will become clearer in the following detailed description of preferred embodiments with reference to the drawings. It should be noted that, prior to a detailed description, it should be understood that similar parts are represented by the same reference numerals.

FIG. 1 shows a first preferred embodiment of an apparatus for recovering tetramethylammonium hydroxide and removing nitrogen-containing compounds from a developing waste solution according to the present invention. The apparatus for removing the water includes a circulation unit 31 and a first adsorption unit 32.

The circulation unit 31 includes a container 311, a circulation pipe 312 connected to the container 311, and a water pump module 313 connected to the container 311, and the container 311 stores developer waste liquid. , the water pump module 313 drives the developer waste liquid to flow in the circulation pipe 312, and the water pump module 313 controls the flow rate of the developer waste liquid in the ionic resin in the first adsorption unit 32. Since control over the flow rate of liquid in piping is a known technique, it will not be described in detail here.

The first adsorption unit 32 is connected to the container 311 and is provided at the outlet of the first ionic resin 321 and the first ionic resin 321 having one inlet (not shown) and one outlet (not shown). a first pH detection module 322 provided at the inlet of the first ionic resin 321, a first electrical conductivity detection module 323 provided at the inlet of the first ionic resin 321, and a second electrical conductivity detection module 324 provided at the outlet of the first ionic resin 321. , a first regeneration module 325 provided at the inlet of the first ionic resin 321 , and a first valve module 326 provided at the outlet of the first ionic resin 321 .

The water pump module 313 injects the developer waste into the first ionic resin 321, the first pH detection module 322 detects the pH value of the first filtrate, and the first electrical conductivity detection module 323 injects the developer waste into the first ionic resin 321. The second electrical conductivity detection module 324 detects the electrical conductivity of the first filtrate, and the first regeneration module 325 injects an acidic solution into the first ionic resin 321. The first valve module 326 controls the liquid discharged from the first ionic resin 321 to be discharged to the outside or returned to the container 311 .

In the first preferred embodiment, the circulation piping 312 runs from the container 311 to the water pump module 313, the first pH detection module 322, the first ionic resin 321, the first electrical conductivity detection module 323, and the first After sequentially passing through the second electrical conductivity detection module 324 and the first valve module 326, it returns to the container 311. In this way, a circulation piping 312 is formed in which the developer waste solution can be circulated. When doing so, the arrangement of the pipeline may be carried out according to the actual site, although it is not limited to the above.

The first ionic resin 321 employs a plurality of positive ion exchange resin towers, and in the first preferred embodiment, the first ionic resin 321 employs three resin towers, and the first ionic resin The resin towers of 321 may be arranged in series or in parallel, and the installation of the resin towers and the connected piping are known techniques and will not be described in detail here. When actually implemented, a plurality of sets of the first ionic resins 321 may be provided, among which one set of the first ionic resins 321 is undergoing ion exchange, and another set of the first ionic resins 321 is in the process of ion exchange. A regeneration process is performed, and regeneration of another set of first ionic resins 321 is completed. The invention is not limited to this example of a preferred embodiment. The first valve module 326 supplies electricity to the water pump module 313, the first pH detection module 322, the first electrical conductivity detection module 323, the second electrical conductivity detection module 324, and the first regeneration module 325, respectively. Among them, the first valve module 326 is a module equipment having a control circuit and water valve parts.

The flow of the method of the first preferred embodiment will be described with reference to FIG. 2, which includes a first adsorption step 901, a first control step 902, a second control step 903, and a third control step. 904.

In the first adsorption step 901, the waste developer in the container 311 is injected into the first ionic resin 321 at a first flow rate, and tetramethylammonium hydroxide and nitrogen-containing compounds in the waste developer are transferred to the first ionic resin. 321 and drain the first filtrate. The pH value of the first filtrate is detected by the first pH detection module 322, and when the first ionic resin 321 with high adsorption power adsorbs ions, the amount of tetramethylammonium hydroxide and nitrogen-containing compounds in the developer waste solution is increased. At this time, the pH measured by the first pH detection module 322 is low, but as the adsorption capacity of the first ionic resin 321 decreases, the pH (pH value) of the first filtrate gradually decreases. and the pH value of the first filtrate flowing out from the first ionic resin 321 is less than a first pH set value, determining that the first filtrate meets the discharge standard and can be directly discharged to the wastewater treatment system; The first valve module 326 controls the first filtrate flowing out from the first ionic resin 321 to flow into the wastewater treatment system, and at this time, the water pump module 313 controls the developer waste liquid at a first flow rate. The first ionic resin 321 is controlled to flow, and preferably, the water pump module 313 controls the first flow rate in the first ionic resin 321 to 2 BV/hr.

In the first control step 902, when the pH of the first filtrate is equal to or higher than the first pH set value, the flow rate at which the waste developer is injected into the first ionic resin 321 is increased to a second flow rate, and The nitrogen-containing compounds in the ionic resin 321 are desorbed, and the first valve module 326 controls the first filtrate flowing out of the first ionic resin 321 to return to the container 311, and the developer waste liquid is transferred to the first valve module 326. The flow rate injected into the first ion resin 321 is increased to a second flow rate. Here, since the pH of the first filtrate is increased to the first pH set value, the nitrogen-containing compounds in the first ionic resin 321 can be desorbed, and preferably, the water pump module 313 The second flow rate in the 1-ion resin 321 is controlled to 4BV/hr or more.

In the first preferred embodiment, the first pH set value is 7, and when actually implemented, the first flow rate and second flow rate in the first ionic resin 321 and the set value of the first pH set value are set. is not limited to this, where the pH of the first filtrate increases to the first pH set value because the dissociation constant of the nitrogen-containing compound is much smaller than that of tetramethylammonium hydroxide; Further, when the flow rate increases to the second flow rate, the tetramethylammonium hydroxide in the developer waste liquid is exchanged with the nitrogen-containing compound in the first ionic resin 321, thereby causing the nitrogen-containing compound in the first ionic resin 321 to Nitrogen compounds are reduced.

In the second control step 903, when the desorption of the nitrogen-containing compounds in the first ionic resin 321 starts, the first filtrate contains many nitrogen-containing compounds, and this causes the electricity of the developer waste solution to increase. The difference between the conductivity and the electrical conductivity of the first filtrate becomes large, and the electrical conductivity of the nitrogen-containing compound is lower than that of tetramethylammonium hydroxide, so the electrical conductivity of the first filtrate is lower than that of the developing waste solution. The electrical conductivity is lower than that of . On the other hand, if the nitrogen-containing compound in the first ionic resin 321 has already decreased, the first filtrate does not contain the nitrogen-containing compound or contains only a small amount of the nitrogen-containing compound, and the developing waste liquid If the electrical conductivity and the electrical conductivity of the first filtrate are very close to each other, and therefore the electrical conductivity of the developer waste solution is close to (substantially the same) as the electrical conductivity of the first filtrate, the electrical conductivity of the first filtrate is The injection of the developer waste solution into the 1-ion resin 321 is stopped. Here, the electrical conductivity of the developer waste liquid is not a constant value, and the electrical conductivity of the first filtrate flowing out from the first ionic resin 321 gradually increases as the adsorption capacity of the first ionic resin 321 decreases. Therefore, when the electrical conductivity of the first filtrate is close to (substantially the same) as the electrical conductivity of the developer waste solution, it is indicated that the nitrogen-containing compound in the first ionic resin 321 is released. Next, the injection of the developer waste liquid into the first ionic resin 321 is stopped, and the third control step 904 is entered, and when actually executed, the water pump module 313 may send the developer waste liquid to another set of first ionic resins 321 that are being regenerated.

In the third control step 904, the first regeneration module 325 controls to apply an acidic solution to the first ionic resin 321 to desorb tetramethylammonium hydroxide in the first ionic resin 321, Drain and collect the tetramethylammonium salt solution. When the first regeneration module 325 regenerates the first ionic resin 321, the first valve module 326 controls the tetramethylammonium salt solution to enter the recovery system, and the recovery system controls the tetramethylammonium salt solution to enter the recovery system. The tetramethylammonium hydroxide in the methylammonium salt solution can be further separated, and the cost of the subsequent regeneration process is reduced because the tetramethylammonium salt solution does not contain or is significantly reduced in nitrogen-containing compounds. In the case where the first ionic resin 321 has completed regeneration, the regenerated first ionic resin 321 will absorb tetramethylammonium hydroxide and other components in the developer waste solution in the first adsorption step 901. Nitrogen compounds can be adsorbed, and thus the first adsorption step 901, the first control step 902, the second control step 903 and the third control step 904 are performed sequentially.

FIG. 3 shows a second preferred embodiment of the present invention, the second preferred embodiment is substantially the same as the first preferred embodiment, the same parts will not be described in detail, and the differences will be explained in the second preferred embodiment. It further includes a suction unit 33.

The second adsorption unit 33 is provided between the outlet of the first ionic resin 321 and the inlet of the container 311, and is a second ionic resin having one inlet (not shown) and one outlet (not shown). 331, a second pH detection module 332 provided at the outlet of the second ionic resin 331, a third electrical conductivity detection module 333 provided at the outlet of the second ionic resin 331, and the second ionic resin 331. an alkaline liquid supply module 334 provided at the inlet of the second ionic resin 331; a second regeneration module 335 provided at the inlet of the second ionic resin 331; and a second valve module 336 provided at the outlet of the second ionic resin 331. ,including.

The water pump module 313 injects the developer waste into the first ionic resin 321, the first pH detection module 322 detects the pH value of the first filtrate, and the first electrical conductivity detection module 323 injects the developer waste into the first ionic resin 321. The second electrical conductivity detection module 324 detects the electrical conductivity of the first filtrate, and the first regeneration module 325 injects an acidic solution into the first ionic resin 321. The first valve module 326 controls the liquid discharged from the first ionic resin 321 to be discharged to the outside or is injected into the second ionic resin 331, and the second pH detection module 332 controls the liquid discharged from the first ionic resin 321 to the outside. The third electrical conductivity detection module 333 detects the electrical conductivity of the second filtrate, and the alkaline solution supply module 334 injects an alkaline solution into the second ionic resin 331. The second regeneration module 335 injects an acidic solution into the second ionic resin 331, and the second valve module 336 controls whether the liquid discharged from the second ionic resin 331 is discharged to the outside or the container 311. control to return to.

The circulation pipe 312 passes from the container 311 through the first ionic resin 321 and the second ionic resin 331 in order, and then returns to the container 311, and the water pump module 313 circulates within the circulation pipe 312. In addition to this, the water pump module 313 can also control the flow rate of the developer waste in the circulation pipe 312, and in the second preferred embodiment, the water pump The module 313 includes a plurality of pressurized water pumps, and these pressurized water pumps are arranged between the water pump and the first ionic resin 321, between the first ionic resin 321 and the second ionic resin 331, and between the first ionic resin 331 and the second ionic resin 331, respectively. The water pump module 313 is provided between the two-ion resin 331 and the container 311, and in actual implementation, although not limited thereto, the water pump module 313 is mainly disposed in the actual piping.

The first ionic resin 321 and the second ionic resin 331 employ a plurality of positive ion exchange resin towers. Preferably, the first ionic resin 321 employs two resin towers, and the second ionic resin 331 employs a plurality of positive ion exchange resin towers. The ionic resin 331 employs two resin towers, and the resin towers of the first ionic resin 321 may be arranged in series or in parallel, and the resin towers of the second ionic resin 331 may be arranged in series or in parallel. As the arrangement of the resin column is well known, it will not be described in detail here. When actually implemented, a plurality of sets of resin towers may be provided for the first ionic resin 321 and the second ionic resin 331, one set of resin towers is in the process of ion exchange of nitrogen-containing compounds, and another set of resin towers is used for ion exchange of nitrogen-containing compounds. One set of resin towers undergoes a regeneration process, and another set of resin towers undergoes a post-regeneration process; however, this preferred embodiment is not intended to be limiting.

The first valve module 326 is electrically connected to the water pump module 313, the first pH detection module 322, the first electrical conductivity detection module 323, the second electrical conductivity detection module 324, and the first regeneration module 325, respectively. The second valve module 336 is connected to the water pump module 313, the second pH detection module 332, the third electrical conductivity detection module 333, the alkaline solution supply module 334, and the second regeneration module 335, respectively. The first valve module 326 and the second valve module 336 are electrically connected, and the first valve module 326 and the second valve module 336 have a control circuit and a water valve component.

The first valve module 326 is provided in the circulation pipe 312 and located between the first ionic resin 321 and the second ionic resin 331, and the first valve module 326 is further provided in a wastewater treatment system (undeveloped). ) and a recovery system (not shown), the second valve module 336 is installed in the circulation pipe 312 and between the second ionic resin 331 and the container 311. The second valve module 336 is further connected to external piping to connect the wastewater treatment system, wherein the wastewater treatment system and the recovery system may be the same treatment system. , but is not limited to this.

Referring to FIG. 4, the flow of the method corresponding to the above device will be explained. The above method includes a first adsorption step 901, a first control step 902, a second control step 903, a third control step 904, a second adsorption step 905, an ion exchange step 906, a waste liquid discharge step 907, a waste liquid recovery step 908, and A resin regeneration step 909 is included.

In the first adsorption step 901, the water pump module 313 is controlled to inject the developer waste solution in the container 311 into the first ionic resin 321, thereby removing tetramethylammonium hydroxide and nitrogen-containing compounds in the developer waste solution. It is adsorbed by the first ionic resin 321, and the first filtrate flows out from the first ionic resin 321. The pH (pH value) of the first filtrate gradually increases as the adsorption capacity of the first ionic resin 321 decreases, and the first pH detection module 322 detects the first filtrate flowing out from the first ionic resin 321. and if the pH value of the first filtrate flowing out from the first ionic resin 321 is less than the first pH set value, the first filtrate meets the discharge standard and is directly discharged to the wastewater treatment system. can do. The first valve module 326 controls the first filtrate flowing out from the first ionic resin 321 to flow into the wastewater treatment system, and at this time, the water pump module 313 controls the developer waste liquid at a first flow rate. The first ionic resin 321 is controlled to flow, and preferably, the water pump module 313 controls the first flow rate in the first ionic resin 321 to 2 BV/hr.

In the first control step 902, when the pH value of the first filtrate flowing out from the first ionic resin 321 is equal to or higher than the first pH setting value, the first filtrate flowing out from the first ionic resin 321 is controlled by the first valve module 326. The first filtrate is controlled to flow into the second ionic resin 331, the flow rate at which the waste developer is injected into the first ionic resin 321 is increased to a second flow rate, and the nitrogen content in the first ionic resin 321 is controlled. The compound is desorbed, and preferably the second flow rate in the first ionic resin 321 is controlled to be 4 BV/hr or more by the water pump module 313. Further, the first pH set value is 7, and in actual implementation, the first flow rate and second flow rate in the first ionic resin 321 and the set value of the first pH set value are limited to this. The first electrical conductivity detection module 323 detects the electrical conductivity of the developing waste solution, and the second electrical conductivity detection module 324 detects the electrical conductivity of the first filtrate. The conductivity is detected, and if the difference between the electrical conductivity of the first filtrate and the developing waste solution is large, the tetramethylammonium hydroxide in the developing waste solution is nitrogen-containing in the first ionic resin 321. In contrast to the compounds, the first filtrate contains a large amount of nitrogen-containing compounds, which indicates that the electrical conductivity is lower than that of the developer waste solution.

In the second control step 903, when the first ionic resin 321 is no longer able to release nitrogen-containing compounds, the electrical conductivity of the first filtrate is close to or substantially the same as the electrical conductivity of the developer waste solution ( If the difference between the electrical conductivity of the first filtrate and the electrical conductivity of the developer waste solution is between ±2 ms/cm, it is defined that the electrical conductivities are close or substantially the same), At this time, the injection of the developer waste liquid into the first ionic resin 321 is stopped. Here, since the electrical conductivity of the developer waste solution is not a constant value, if the electrical conductivity of the first filtrate is close to (or substantially the same as) the electrical conductivity of the developer waste solution, the nitrogen-containing compound It is shown that it is no longer possible to separate from the first ionic resin 321, and therefore, the injection of the developer waste solution into the first ionic resin 321 is stopped, and the third control step 904 is entered and the actual execution is performed. Sometimes, but not limited to, the water pump module 313 may introduce the developer waste to another set of regenerated first ionic resins 321.

In the third control step 904, the first regeneration module 325 is controlled to apply an acidic solution to the first ionic resin 321 to desorb tetramethylammonium hydroxide in the first ionic resin 321, and to remove tetramethylammonium hydroxide from the first ionic resin 321. Obtain ammonium salt solution. When the first regeneration module 325 regenerates the first ionic resin 321, the first valve module 326 controls the tetramethylammonium salt solution to enter the recovery system, and the recovery system controls the tetramethylammonium salt solution to enter the recovery system. If tetramethylammonium hydroxide containing no nitrogen compounds can be separated from the methylammonium salt solution and the first ionic resin 321 has completed regeneration, the first adsorption step 901, the second adsorption step 902, After performing the second control step 903 and the third control step 904, the regenerated first ionic resin 321 can adsorb tetramethylammonium hydroxide and nitrogen-containing compounds in the developer waste solution in the first adsorption step 901. can.

In the second preferred embodiment, when executing the first control step 902, if the pH of the first filtrate is equal to or higher than the first pH setting value, the developer waste liquid is injected into the first ionic resin 321. The flow rate is increased to a second flow rate to desorb the nitrogen-containing compound in the first ionic resin 321, and the second adsorption step 905 is executed.

In the second adsorption step 905, the pH of the first filtrate is equal to or higher than the first pH set value, and the flow rate in the first ionic resin 321 increases to a second flow rate, and the flow rate in the first ionic resin 321 increases to a second flow rate. Since the nitrogen-containing compounds in the first filtrate are released, the first valve module 326 controls the first filtrate to flow into the second ionic resin 331, and the second ionic resin 331 discharges the tetrachloride in the first filtrate. When adsorbing methyl ammonium and nitrogen-containing compounds, the second ionic resin 331 discharges a second filtrate, and the second ionic resin 331 is unsaturated (the pH of the second filtrate is less than a second pH set value). , the nitrogen-containing compounds in the first filtrate can be effectively adsorbed, so that the second filtrate meets the discharge standard, and the second valve module 336 allows the second filtrate to be discharged to the wastewater treatment system. Even if the first ionic resin 321 repeatedly executes the first adsorption step 901, the second adsorption step 902, the second control step 903, and the third control step 904, the second valve Module 336 controls the second filtrate to be discharged to the wastewater treatment system. When the second ionic resin 331 is saturated, the injection of the first filtrate into the second ionic resin 331 is immediately stopped, and when actually carried out, the first The filtrate may be discharged to another set of regenerated second ionic resins 331 .

If the pH of the second filtrate is equal to or higher than the second pH set value, it is indicated that the second ionic resin 331 is saturated, and therefore the ion exchange step 906, the waste liquid discharge step 907, the waste liquid collection Step 908 and the resin regeneration step 909 are performed sequentially, and preferably the second pH setting value is 7, but when actually implemented, it is not limited to this.

In the ion exchange step 906, when the pH of the second filtrate is equal to or higher than the second pH setting value, injection of the first filtrate into the second ionic resin 331 is stopped, and the second ionic resin 331 is alkaline. Apply a solution (sodium hydroxide or potassium hydroxide). Ions contained in the alkaline solution (for example, sodium ions or potassium ions) can undergo ion exchange with the nitrogen-containing compound or tetramethylammonium ion in the second ionic resin 331, and here, this ion exchange is performed in a pre-regeneration process. The nitrogen-containing compound may be discharged from the alkaline solution discharged from the second ionic resin 331, and then the tetramethylammonium ion may be discharged. Note that the concentration of the alkaline solution used in the pre-regeneration process can change the degree of ion exchange, so if the concentration of the alkaline solution is within an appropriate range, the nitrogen-containing compound in the second ionic resin 331 and The separation of tetramethylammonium ion can be carried out effectively, and preferably the alkaline solution used may be sodium hydroxide or potassium hydroxide, but when actually carried out, other alkaline solutions or water may be used. Other alkaline solutions containing sodium oxide or potassium hydroxide may also be used.

As a result of measurements by the present inventors, if the concentration of the alkaline solution is too high or too low, the nitrogen-containing compound or tetramethylammonium ion in the second ionic resin 331 cannot be effectively released, In the second preferred embodiment, the concentration of the alkaline solution is between 0.1% and 2% by weight, and since the concentration of the alkaline solution used in the pre-regeneration process varies the degree of ion exchange, this concentration range (0.1 wt% to 2 wt%), the sodium ions or potassium ions in the alkaline solution can perform ion exchange with the nitrogen-containing compound of the second ion resin 331, thereby causing the second ion The nitrogen-containing compounds and tetramethylammonium ions in the resin 331 are effectively separated, and when actually carried out, the concentration of the alkaline solution is such that the nitrogen-containing compounds are discharged and the tetramethylammonium hydroxide recovery effect is the best. It may be adjusted according to the actual situation in consideration of the above, and when the nitrogen-containing compound in the second ionic resin 331 is effectively released from the alkaline solution, the waste liquid discharging step 907 is performed. executed.

In the waste liquid discharge step 907, the second ionic resin 331 is saturated and an alkaline solution is applied to the second ionic resin 331. Utilizing the characteristic that methylammonium is much smaller than that of methylammonium, the ions in the alkaline solution preferentially exchange with the nitrogen-containing compound in the second ionic resin 331 instead of with the tetramethylammonium ion. Since the electrical conductivity of the nitrogen compound is lower than that of tetramethylammonium hydroxide, if the electrical conductivity of the alkaline solution flowing out from the second ionic resin 331 is less than the electrical conductivity setting value, the second ionic resin The alkaline solution entering the alkaline solution 331 and the nitrogen-containing compound in the second ionic resin 331 are surely performing ion exchange, and the solution discharged from the second ionic resin 331 contains a large amount of nitrogen-containing compound. and does not contain tetramethylammonium hydroxide, indicating that the discharged liquid satisfies the discharge standards, and the second valve module 336 discharges the alkaline solution discharged from the second ionic resin 331. is discharged into the above wastewater treatment system.

In the waste liquid recovery step 908, when the nitrogen-containing compounds in the second ionic resin 331 are gradually released from the alkaline solution, only tetramethylammonium ions remain in the second ionic resin 331, and then, The ions (for example, sodium ions or potassium ions) contained in the alkaline solution undergo ion exchange with the tetramethylammonium ions in the second ionic resin 331, whereby the alkaline solution (sodium hydroxide or potassium hydroxide) becomes hydroxylated. Since the solution contains tetramethylammonium and tetramethylammonium hydroxide has high electrical conductivity, the electrical conductivity of the liquid discharged from the second ionic resin 331 improves, and therefore the second ionic resin 331 has a high electrical conductivity. When the electrical conductivity of the alkaline solution flowing out from the alkaline solution 331 is equal to or higher than the electrical conductivity setting value, it is indicated that the second ionic resin 331 is releasing tetramethylammonium hydroxide. The valve module 336 drains the solution containing tetramethylammonium hydroxide from the second ionic resin 331 and returns it to the container 311, thereby recovering the tetramethylammonium hydroxide and completing the predetermined amount of alkaline solution. After that, the alkaline solution supply module 334 stops injecting the alkaline solution into the second ionic resin 331, where the electrical conductivity setting value is 400 us/cm, and the alkaline solution is sodium hydroxide or water. potassium oxide, the acidic solution is hydrochloric acid, and when actually implemented, the first pH setting value, the second pH setting value, the electrical conductivity setting value, the components of the alkaline solution, and the components of the acidic solution are It is not limited to the above.

In the resin regeneration step 909, the alkaline solution supply module 334 stops injecting the alkaline solution into the second ionic resin 331, the second ionic resin 331 is filled with ions from the alkaline solution, and then 2 regeneration module 335 is controlled to apply an acidic solution to the second ionic resin 331, the acidic solution desorbs ions (e.g., sodium ions or potassium ions) from the alkaline solution in the second ionic resin 331, and The second ionic resin 331 can be regenerated, which is defined as a post-regeneration process, and the technique of regenerating the resin with an acidic solution is well known, so it will not be described in detail here, and the regenerated second ion resin 331 can be regenerated. The resin 331 is prepared for the next second adsorption step 905.

The above method mainly utilizes the fact that "the dissociation constant of nitrogen-containing compounds is much smaller than that of tetramethylammonium hydroxide." Therefore, in the present invention, nitrogen-containing compounds can be removed under high pH conditions. Taking advantage of the fact that it is difficult to become a cation, the tetramethylammonium ion in the developer waste solution is exchanged with the nitrogen-containing compound in the first ionic resin 321 to remove most of the nitrogen-containing compound, and then the second By adsorbing such a high pH solution with the ionic resin 331, the problem of not being able to discharge strong alkaline or high nitrogen wastewater is avoided.

Further, after the second ionic resin 331 becomes saturated, the nitrogen-containing compound is easily exchanged with cations in the alkaline solution due to the high pH condition, and as a result, the nitrogen-containing compound is separated from the tetramethylammonium ion. In this way, the tetramethylammonium ions are effectively recovered, thereby achieving the purpose of effectively removing nitrogen-containing compounds and recovering the tetramethylammonium ions. Finally, the second ionic resin 331 is regenerated using an acidic solution.

experiment

In the first experiment, a developer waste solution with a low concentration of tetramethylammonium ions was used, and the developer waste solution was adsorbed by the first ionic resin 321 to determine the concentration of each compound in the developer waste solution and the tetramethylammonium salt solution. It is shown in Table 1. The result of measuring the pH value at the outlet end of the first ionic resin 321 is greater than 7, the flow rate increases to 4BV/hr, and the first valve module 326 is controlled to turn the valve to the second ionic resin 331. When the electric conductivity at the outlet end of the first ionic resin 321 becomes equal to the electric conductivity at the inlet end, the flow rate is reduced and the reserve column of the first ionic resin 321 is used to drain the developing waste liquid. Sustains adsorption. As a result of calculating the adsorption and desorption of the first ionic resin 321, the removal rate is at least greater than 80%. Ions (NH4+) and monoethanolamine (MEA) are smaller than 10 ppm and 25 ppm, respectively. Therefore, when the pH value of the developer waste solution is improved and the flow rate injected into the first ionic resin 321 is increased, The nitrogen-containing compounds (ammonium ions (NH4+) and monoethanolamine (MEA)) adsorbed by the first ionic resin 321 are removed, and the concentration of the tetramethylammonium salt (TMA+) is increased in the first filtrate. At the same time, the concentration of the nitrogen-containing compound can be improved, and detailed data are shown in Table 1.

In the second experiment, the experimental conditions of the second experiment were almost the same as the first experiment, except that the concentration of tetramethylammonium ions in the developer waste solution was increased (TMA+ increased from 1359 ppm to 3540 ppm). The data are shown in Table 2.

In the third experiment, the experimental conditions of the third experiment were almost the same as those of the second experiment, except that the monoethanolamine concentration in the developer waste solution was further increased (MEA increased from 50 ppm to 123 ppm). The data are shown in Table 3.

Next, a fourth experiment, which is a control experiment, was conducted. In the fourth experiment, the developer waste solution was adsorbed by the first ionic resin 321 without increasing the flow rate of the developer waste solution, and the developer waste solution and the tetramethyl The concentration of each compound in the ammonium salt solution is shown in Table 4, and if the pH value measured at the outlet end of the first ionic resin 321 is greater than 7, the adsorption is stopped. Next, the first ionic resin 321 was regenerated with an acid solution, and ammonium ions (NH4+) and monoethanolamine (MEA) were detected in the regenerated and recovered liquid (tetramethylammonium salt solution) obtained. Detailed data are shown in Table 4, and as a result of comparing the fourth experiment with the first to third experiments, it was found that under conditions where the flow rate is not increased, ammonium ions (NH4+) and monoethanolamine of the first ionic resin 321 (MEA) removal rate was lower than 50%, and ammonium ions (NH4+) and monoethanolamine (MEA) were measured in the regenerated recovery liquid (tetramethylammonium salt solution) obtained by regeneration with an acidic solution. It was found that the nitrogen-containing compounds in the tetramethylammonium salt solution were not reliably separated.

As can be seen from the data of the first to third experiments, ammonium ions and monoethanolamine can be effectively removed by the combination of high pH and high flow rate, regardless of the concentration of tetramethylammonium ions in the developer waste solution. In addition, as a result of comparison with the fourth experiment above, by increasing both the pH and flow rate of the operation, ammonium ions and monoethanolamine in the regenerated recovery liquid were effectively removed, and regeneration with an acidic solution was achieved. The load on subsequent processes can be reduced without affecting the total amount of the regenerated recovery liquid (recovered tetramethylammonium salt solution) obtained.

In addition to this, when the first ionic resin 321 is saturated, high pH (pH) development is achieved where the tetramethylammonium ions in the developer waste solution can exchange with the nitrogen-containing compounds in the first ionic resin 321. Waste liquid is used. The first filtrate discharged from the first ionic resin 321 contains tetramethylammonium ions at a high concentration, and if the first filtrate is not adsorbed, the discharge of waste water becomes a problem. The second adsorption unit 33 is installed after the adsorption unit 32 to perform secondary adsorption, that is, pre-regeneration with 1% concentration of sodium hydroxide (even if the concentration range is 0.1wt% to 2wt%). By doing this, the purpose of wastewater treatment and the effective recovery of tetramethylammonium ions can be realized.

The second ionic resin 331 receives the alkaline first filtrate with a high nitrogen content discharged from the first ionic resin 321, and the concentration of each compound in this first filtrate is shown in Table 5 below, and the second ionic resin If the pH at the outlet of the resin 331 is >7, the valve is switched to the reserve tower of the second ionic resin 331 to continue adsorption, and then the saturated second ionic resin 331 is added to 1% sodium hydroxide. to play the previous playback. In the pre-regeneration, if the electrical conductivity at the outlet of the second ionic resin 331 is less than 400 us/cm, the waste liquid containing the nitrogen-containing compound is discharged to a wastewater treatment plant and disposed of; When the electrical conductivity at the outlet of the resin 331 is 400 us/cm or more, the outlet is switched to the container 311, and the sodium ions in the alkaline solution are exchanged with the tetramethylammonium ions in the second ionic resin 331, and water is removed. Immediately after a predetermined amount of 1% sodium hydroxide (NaOH) is sent to the second ionic resin 331 as a solution containing tetramethylammonium oxide, the pre-regeneration is stopped, and finally, the second ionic resin 331 is Prepare for use by desorbing sodium ions in acidic solution.

In the fifth experiment, the compound adsorbed by the second ionic resin 331 is a waste liquid with a high concentration of tetramethylammonium ions discharged to the first ionic resin 321, and the pH at the outlet of the second ionic resin 331 is >7, stop the adsorption, perform pre-regeneration with 1% sodium hydroxide at a flow rate of 1 BV/hr, drain the waste solution, and sample for ammonium ions, monoethanolamine, and tetramethylammonium ions. The concentration was obtained by analysis, the electrical conductivity was measured, and the wastewater discharge method at the outlet (acceptable waste liquid or recovered waste liquid) was determined.The analytical data is shown in Table 5, where the supply concentration is the same as above. The components of the first filtrate entering the second ionic resin 331, the above-mentioned passed waste liquid are the components of the discharged liquid when the electric conductivity at the outlet of the second ionic resin 331 is 400 us/cm, and the recovered waste liquid is the above-mentioned component. This is a component of the discharged liquid when the electrical conductivity at the outlet of the second ionic resin 331 is 400 us/cm or more. As can be seen from Table 5 below, when the electrical conductivity at the outlet of the second ionic resin 331 is less than 400 us/cm, sodium ions in the alkaline solution undergo ion exchange only with nitrogen-containing compounds, and tetramethyl There is no ion exchange with ammonium, and therefore, the passed waste liquid contains many nitrogen-containing compounds (NH4+ and MEA) and little tetramethylammonium (TMA+). Therefore, the passed waste liquid is sent directly to the outside. If the electrical conductivity at the outlet of the second ionic resin 331 is 400 us/cm or more, the alkaline solution will not be able to absorb the second ion because there is only a small amount of nitrogen-containing compound in the second ionic resin 331. Ion exchange can be performed with the tetramethylammonium in the resin 331, and as a result, the recovered waste liquid contains less nitrogen-containing compounds (NH4+ and MEA) and more tetramethylammonium (TMA+). The objective of recovering tetramethylammonium hydroxide (TMAH) is achieved.

In the sixth experiment, the experimental conditions of the sixth experiment were almost the same as those of the fifth experiment, except that the concentration of tetramethylammonium ions supplied to the second ionic resin 331 was changed, and detailed data are shown in Table 6.

As can be seen from the experimental data in Tables 5 and 6, the tetramethylammonium ion waste liquid discharged from the first ionic resin 321 can be further adsorbed using the second ionic resin 331. Solution: The first ionic resin 321 solves the problem of highly alkaline wastewater with high nitrogen content discharged to remove other nitrogen-containing compounds. Even when the second ionic resin 331 becomes saturated, it can be regenerated using an alkaline solution and about 96% of the tetramethylammonium ions can be recovered.

As can be seen from the above description, it is clear that the method of recovering tetramethylammonium hydroxide in the developer waste solution and removing nitrogen-containing compounds according to the present invention has the following effects.

1. Removing nitrogen-containing compounds In the present invention, the first ionic resin 321 is saturated by utilizing the characteristic that "the dissociation constant of nitrogen-containing compounds is much smaller than that of tetramethylammonium hydroxide." Sometimes, the nitrogen-containing compound in the first ionic resin 321 is reduced by using a high-pH developer waste solution and exchanging tetramethylammonium hydroxide in the developer waste solution with the nitrogen-containing compound in the first ionic resin 321. is decreased, and tetramethylammonium hydroxide in the first ionic resin 321 is increased.

2. Reducing the recovery cost After removing the nitrogen-containing compounds in the first ionic resin 321, the ions adsorbed in the first ionic resin 321 become highly pure tetramethylammonium hydroxide, and the acidic solution When the first ionic resin 321 is regenerated, the tetramethylammonium hydroxide in the first ionic resin 321 can be removed to obtain the tetramethylammonium salt solution, and the tetramethylammonium salt solution containing no nitrogen-containing compound can be obtained. By creating a methylammonium salt solution, it is possible to reduce the subsequent regeneration and recovery steps, eliminate the adverse effects of purification and electrodialysis, and reduce recovery costs.

3. Recovering the resin to meet the waste liquid discharge standards After adsorbing the waste water, the second adsorption unit 33 after the first adsorption unit 32 can undergo pre-regeneration with 1% sodium hydroxide. In this way, the purpose of wastewater treatment and the effective recovery of tetramethylammonium ions are realized, and the alkaline solution can undergo ion exchange to remove nitrogen-containing compounds, and the electrical conductivity of the discharged alkaline solution is improved. If the rate is less than 400 us/cm, it meets the discharge standards and can be discharged to the wastewater treatment system, and the acidic solution used for post-regeneration desorbs the tetramethylammonium hydroxide in the second ionic resin 331. , the second ionic resin 331 can be regenerated and recovered.

4. Release of nitrogen-containing compound twice In the present invention, the pH of the first filtrate is increased to the first pH set value using the saturated first ionic resin 321, and the first ionic resin 321 is 2 By controlling the flow rate to 4 BV/hr or more, the tetramethylammonium hydroxide in the developer waste liquid replaces the nitrogen-containing compound in the first ionic resin 321. The nitrogen-containing compound is released, that is, the first nitrogen-containing compound release is performed, and when sodium hydroxide in the alkaline solution is used, the nitrogen-containing compound in the second ionic resin 331 is released, and then the nitrogen-containing compound is released. The tetramethylammonium ion in the second ionic resin 331 is released, that is, the nitrogen-containing compound is released for the second time, and the alkaline solution discharged from the second ionic resin 331 satisfies the discharge standards, and the The recovery rate of tetramethylammonium hydroxide can be improved.

As described above, in the present invention, after increasing the pH value of the developer waste solution and increasing the flow rate of the developer waste solution, the nitrogen-containing compound in the first ionic resin 321 is released, and the nitrogen-containing compound-free tetramethyl An ammonium salt solution can be obtained. The second ionic resin 331 adsorbs nitrogen-containing compounds and tetramethylammonium ions in the first filtrate, and also releases the nitrogen compounds in the second ionic resin 331 through pre-regeneration with an alkaline solution. The tetramethylammonium hydroxide in the second ionic resin 331 can be recovered from the above, and the nitrogen compounds discharged from the second ionic resin 331 meet the waste liquid discharge standards, thus achieving the purpose of the present invention. can be achieved.

The above are just two preferred embodiments of the present invention, and these do not limit the scope of implementation of the present invention, and any simple equivalent changes or modifications made based on the contents of the present invention can be applied to the present invention. falls within the scope of patents.

31 Circulation unit 311 Container 312 Circulation piping 313 Water pump module 32 First adsorption unit 321 First ionic resin 322 First pH detection module 323 First electrical conductivity detection module 324 Second electrical conductivity detection module 325 First regeneration module 326 1 valve module 33 2nd adsorption unit 331 2nd ionic resin 332 2nd pH detection module 333 3rd electrical conductivity detection module 334 Alkaline liquid supply module 335 2nd regeneration module 336 2nd valve module 901 1st adsorption step 902 1st control Step 903 Second control step 904 Third control step 905 Second adsorption step 906 Ion exchange step 907 Waste liquid discharge step 908 Waste liquid recovery step 909 Resin regeneration step

Claims (10)

A method for removing nitrogen-containing compounds by recovering tetramethylammonium hydroxide in a developer waste solution, the method comprising:
A first method for injecting a developer waste solution in a container into a first ionic resin at a first flow rate, adsorbing tetramethylammonium hydroxide and nitrogen-containing compounds in the developer waste solution with the first ionic resin, and flowing out a first filtrate. an adsorption step;
When the pH of the first filtrate is equal to or higher than a first pH set value, increasing the flow rate at which the developer waste solution is injected into the first ionic resin to a second flow rate to desorb nitrogen-containing compounds in the first ionic resin. a first control step;
a second control step of stopping the injection of the developer waste solution into the first ionic resin when the electrical conductivity of the developer waste solution is close to the electrical conductivity of the first filtrate;
a third control step of applying an acidic solution to the first ionic resin to desorb tetramethylammonium hydroxide in the first ionic resin to obtain a tetramethylammonium salt solution. Tetramethyl hydroxide in the developer waste solution according to claim 1, wherein in the first adsorption step, the first flow rate is 2 BV/hr, and in the first control step, the second flow rate is 4 BV/hr or more. A method for recovering ammonium and removing nitrogen-containing compounds. 2. The method for removing nitrogen-containing compounds by recovering tetramethylammonium hydroxide in a developer waste solution according to claim 1, wherein in the first control step, the first pH setting value is 7. further comprising a second adsorption step after the first adsorption step,
In the second adsorption step, when the electrical conductivity of the developer waste solution is different from the electrical conductivity of the first filtrate, the first filtrate is injected into a second ionic resin to absorb tetrahydroxide in the first filtrate. 2. The method for removing nitrogen-containing compounds by recovering tetramethylammonium hydroxide in a developer waste solution according to claim 1, wherein methylammonium and nitrogen-containing compounds are adsorbed and a second filtrate is discharged. further comprising an ion exchange step after the second adsorption step, and a resin regeneration step after the ion exchange step,
In the ion exchange step, if the pH of the second filtrate is equal to or higher than a second pH set value, injection of the first filtrate into the second ionic resin is stopped and an alkaline solution is applied to the second ionic resin. death,
5. Recovering tetramethylammonium hydroxide in the developer waste solution according to claim 4, wherein in the resin regeneration step, injection of the alkaline solution into the second ionic resin is stopped and an acidic solution is applied to the second ionic resin. method to remove nitrogen-containing compounds. 6. In the ion exchange step, the second pH set value is 7, and the concentration of the alkaline solution is 0.1% to 2%. Method for removing nitrogen-containing compounds. further comprising a waste liquid discharge step after the ion exchange step, and a waste liquid recovery step between the waste liquid discharge step and the resin regeneration step,
In the waste liquid discharging step, if the electrical conductivity of the alkaline solution flowing out from the second ionic resin is less than an electrical conductivity setting value, discharging the second filtrate to the outside,
5. In the waste liquid recovery step, if the electrical conductivity of the alkaline solution flowing out from the second ionic resin is equal to or higher than the electrical conductivity setting value, the alkaline solution flowing out from the second ionic resin is returned to the container. A method for removing nitrogen-containing compounds by recovering tetramethylammonium hydroxide in a developer waste solution as described in . 8. The method for removing nitrogen-containing compounds by recovering tetramethylammonium hydroxide in a developing waste solution according to claim 7, wherein in the waste liquid discharging step and the waste liquid collecting step, the electrical conductivity setting value is 400 us/cm. An apparatus for recovering tetramethylammonium hydroxide in a developer waste solution and removing nitrogen-containing compounds,
Applied to the method of recovering tetramethylammonium hydroxide in the developer waste solution and removing nitrogen-containing compounds according to claims 1 to 3,
a circulation unit including a container containing developer waste liquid and a water pump module connected to the container;
a first ionic resin connected to the container; a first pH detection module provided at the outlet of the first ionic resin; a first electrical conductivity detection module provided at the inlet of the first ionic resin; A second electrical conductivity detection module provided at the outlet of the first ionic resin, a first regeneration module provided at the inlet of the first ionic resin, and a first valve provided at the outlet of the first ionic resin. module, the water pump module injects the developer waste into the first ionic resin, the first regeneration module injects an acidic solution into the first ionic resin, and the first valve module injects the first ionic resin into the first ionic resin. a first adsorption unit that controls the liquid discharged from the one-ion resin to be discharged to the outside or returned to the container. An apparatus for recovering tetramethylammonium hydroxide in a developer waste solution and removing nitrogen-containing compounds, the apparatus recovering tetramethylammonium hydroxide in the developer waste solution and removing nitrogen-containing compounds according to claims 1 to 8. applied to the method,
a circulation unit including a container containing developer waste liquid and a water pump module connected to the container;
A first ionic resin provided at the outlet of the container, a first pH detection module provided at the outlet of the first ionic resin, and a first electrical conductivity detection module provided at the inlet of the first ionic resin. , a second electrical conductivity detection module provided at the outlet of the first ionic resin, a first regeneration module provided at the inlet of the first ionic resin, and a second electrical conductivity detection module provided at the outlet of the first ionic resin. a first adsorption unit, the water pump module injecting the developer waste into the first ionic resin, and the first regeneration module injecting an acidic solution into the first ionic resin;
a second ionic resin provided between the outlet of the first ionic resin and the inlet of the container; a second pH detection module provided at the outlet of the second ionic resin; and a second pH detection module provided at the outlet of the second ionic resin. a third electrical conductivity detection module provided, an alkaline solution supply module provided at the inlet of the second ionic resin, a second regeneration module provided at the inlet of the second ionic resin, and the second ion a second valve module installed at a resin outlet, the alkaline solution supply module injecting the alkaline solution into the second ionic resin, and the second regeneration module injecting the acidic solution into the second ionic resin. The first valve module controls the liquid discharged from the first ionic resin so that it is discharged to the outside or is injected into the second ionic resin, and the second valve module controls the liquid discharged from the first ionic resin. a second adsorption unit that controls the liquid discharged from the two-ion resin to be discharged to the outside or returned to the container.

Images