JP2006061828A - Method for producing acid water and alkaline water - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing acid (alkaline) water which can be obtained immediately at a site without purchasing/treating with a chemical including a powerful medicine and used for cleaning a metal, a resin, a circuit board or the like or adjusting the pH of soil, waste water, cement, mortar or the like. <P>SOLUTION: This method for producing acid (alkaline) water comprises a step of setting a transportable new or regenerated cation (anion) exchange column, a step of supplying raw water having the pH of ≥6 and ≤8 to the cation (anion) exchange column, a step of using the acid (alkaline) treated water obtained from the cation (anion) exchange column as a cleaning agent or a pH adjusting agent, a step of discriminating the pH of the treated water and a plurality of steps of opening/closing predetermined valves, supplying a strong acid (base) to the cation (anion) exchange column by injection and regenerating the function of the cation (anion) exchange column when the pH value of the treated water is outside a stipulated range. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for producing acidic water and alkaline water, and in particular, at the site of cleaning metals, resins, circuit boards, etc., or pH adjustment of soil, waste (waste) water, cement, mortar, etc. The present invention relates to a method for producing acidic water and alkaline water that can be immediately performed using makeup water that is usually available on site.

  When cleaning metal products, resin products, or circuit boards and other composites of metals and resins, cleaning water having a pH suitable for the nature of the soiling of the object is required. If within range, other properties such as purity for a particular substance are not necessarily critical.

  Moreover, when adjusting the pH of soil, waste (waste) water, cement, mortar, etc., pH-adjusted water that can neutralize (can be adjusted to about pH 7) by canceling the original pH of the object is necessary. As pH-adjusted water, other properties such as purity with respect to a specific substance are not critical as long as the pH is in a desired range.

  Conventionally, even in such a case, acid water or alkaline water having certain characteristics related to other properties such as a certain pH and purity with respect to a specific substance is prepared and stored in advance and brought to the site or on site. It has been necessary to produce acidic water or alkaline water having a predetermined pH by bringing in raw materials and performing some chemical reaction or dissolution reaction.

  When storing, transporting, or reacting these acidic water, alkaline water, or their raw materials, they must be purchased and treated as chemicals, and handling as powerful drugs may be necessary. It was expensive and expensive.

  The object of the present invention is to solve the above-mentioned problems, and it is not necessary to purchase and process chemicals including powerful drugs, and can be immediately performed on site, and can be performed immediately on the spot, for washing acidic water for cleaning metals, resins, circuit boards and the like, and Another object of the present invention is to provide a method for producing acidic water for adjusting pH, such as soil, waste (waste) water, cement, and mortar.

  Another object of the present invention is to solve the above-mentioned problems, and it is not necessary to purchase and process chemicals including powerful drugs, and can be immediately executed on site, for washing metals, resins, circuit boards and the like, alkaline. It is to provide a method for producing water and alkaline water for adjusting pH of soil, waste (waste) water, cement, mortar and the like.

  In order to achieve the above object, the method for producing acidic water according to the first aspect of the present invention includes the step of setting a new or regenerated product of a portable cation (cation) exchange tower, opening and closing a predetermined valve, supplying raw water having a pH of 6 or more and 8 or less to the cation exchange column, a step of using the acidic treated water obtained from the cation exchange column for the purpose of washing or pH adjustment, and the treated water And determining the pH of the treated water, and when the pH value of the treated water is out of a specified range, opens and closes a predetermined valve to supply a strong acid for chemical injection to the cation exchange column, and the function of the cation exchange column And a plurality of steps for reproducing.

Further, the method for producing alkaline water according to the second aspect of the present invention comprises a step of setting a new or regenerated portable anion (anion) exchange column, opening and closing a predetermined valve, and a pH of 6 or more. A step of supplying raw water of 8 or less to the anion exchange column, a step of using the alkaline treated water obtained from the anion exchange column for the purpose of washing or pH adjustment, and determining the pH of the treated water Steps,
When the pH value of the treated water is out of a specified range, a plurality of steps for regenerating the function of the anion exchange column by opening and closing a predetermined valve and supplying a strong alkali for chemical injection to the anion exchange column; It is characterized by including.

  According to the method for producing acidic water according to the present invention, it is possible to obtain acid water in a necessary amount immediately at the site using makeup water that is usually available. There is no need for dangerous handling work, and metals, resins, circuit boards, and the like can be washed inexpensively and safely, and the pH of soil, waste (waste) water, cement, mortar, etc. can be adjusted.

  According to the method for producing alkaline water according to the present invention, it is possible to obtain alkaline water in a necessary amount immediately on site using makeup water that is usually available. There is no need for dangerous handling work, and metal, resin, circuit board, etc. can be washed inexpensively and safely, and pH adjustment of soil, waste (waste) water, cement, mortar, etc. can be performed.

  Embodiments according to the present invention will be specifically described below with reference to the drawings.

  1 and 2 are diagrams for explaining a method for producing acidic water according to a first embodiment of the present invention. FIG. 1 is a flowchart, and FIG. 2 is a schematic diagram of a corresponding apparatus.

In FIG. 2, a cation exchange column 20 containing a strong acid cation (cation) exchange resin 22 that is not used or is being used is passed through stage 2 in FIG. 1 described later, that is, HCl (hydrochloric acid), H _2. When chemicals such as SO ₄ (sulfuric acid) are used, cations such as Ca ⁺ , Mg ⁺ , Na ⁺ , K ⁺ , etc. bound to the strongly acidic cation exchange resin are replaced with H ⁺ ions, that is, cation exchange. The H ⁺ ion, which is a characteristic of the resin, can be electrodeposited onto a strongly acidic cation exchange resin, so that the cation exchange tower can be made into a recycled product equivalent to a new product.

The pH of make-up water in a normal field such as city water, well water, industrial water, middle water, seawater, etc. is about 6-8.
However, seawater is not practical in general since the ion exchange capacity of the ion exchange resin is lost immediately unless actually diluted with other make-up water, for example.
However, for example, replenishing water mixed with seawater, such as washing, washing and drainage of objects immersed in seawater, can be used as raw water in this embodiment.

In FIG. 2, this makeup water is referred to as raw water 40.
As shown in stage 1 (raw water treatment) of FIG. 1, in step 1, a new or regenerated cation exchange tower is set, and in step 2, valves 1, 2, 3, 4, 5 of FIG. Close 6, 7, 8, 9, 10.
Then, in FIG. 2, raw water 40 is supplied to the cation exchange column 20, and the chemical injection strong acid (HCl or H ₂ SO ₄ ) 30 is not supplied to the cation exchange column 20, so only the raw water is converted into a strongly acidic cation exchange resin, for example, Water is passed at a water passage speed of LV 20 m / hour.

H ⁺ (Hydrogen ion), which was contained in a neutral salt or alkali form in the raw water, and a cation such as Ca ⁺ , Mg ⁺ , Na ⁺ , K ⁺ , etc. was electrodeposited on a strongly acidic cation resin ) And H + in the treated water after passing water roughly corresponds to the charge equivalent of cations such as Ca ⁺ , Mg ⁺ , Na ⁺ , K ⁺ , etc. contained in the form of neutral salts Increase by minutes.

As a result, the treated water that has passed through the water collecting plate 24 becomes acidic regardless of the pH of the raw water, and when the pH of the treated water 50 is monitored by a pH meter 93, for example, it is a standard strongly acidic cation exchange resin. In the case of a styrene-DVB (Di-Vinyl-Benzene) copolymer having a sulfo group (—SO ₃ H) as an ion exchange group, 2.9 to 3.4 are shown.

The H ⁺ ions in the produced treated water 50 exist stably, for example, pH = 2.9 after 6 months from the production date, pH = 3.2 after 1 year, and the pH is slightly even after a long time. It has the feature that it only fluctuates.

The reason why the pH slightly increases with the passage of time is that the acidity decreases due to the gradual evaporation of CO ₂ contained as carbonic acid contained in the treated water.
Thus, the treated water 50 once produced exhibits acidity and its pH is stable.

Referring to step 3A of stage 1 in FIG. 1, for the purpose of cleaning, an object containing an acid-soluble substance attached to the surface of an organic substance or a metal is immersed in treated water 50 or in the object. When treated water is sprayed, H ⁺ begins to react with the organic or acid soluble material.
As a result of the above reaction, the organic substance is decomposed, and the acid-soluble substance is decomposed and dissolved in the treated water.

  As an example, when the 10-yen coin normally used in the treated water 50 having a pH of 2.9 is put and observation is continued for 3 hours to 6 hours to 12 hours, the surface of the coin can be visually confirmed. Changed as follows, and the pH of the treated water changed as follows.

After 3 hours had passed, the dirt (organic matter) on the surface of the 10-yen coin gradually peeled off, and the pH at that time was 3.8.
After 6 hours, about 60% of the dirt (organic matter) on the surface of the 10 yen coin was peeled off, and the pH at that time was 4.5.
After 12 hours had passed, 99% of the dirt (organic matter) on the surface of the 10-yen coin was peeled off, and the pH at that time was 5.9.

In consideration of this, acidic water having a pH of 2.9 reacted with an organic substance or the like attached to the metal surface to decompose the organic substance, so that the organic substance was peeled from the coin.
As proof, the pH of the treated water gradually increased, that is, the acidity of the treated water decreased as the decomposition of organic matter progressed.

  When the final pH of the treated water 50 reaches the standard pH range of the wastewater of the country and each prefecture, there is no problem even if it is discharged as it is.

  Referring to step 3B of stage 1 in FIG. 1, the acidic treated water 50 produced as described above for the purpose of pH adjustment is the pH of objects such as soil, waste (waste) water, cement, and mortar. When adjusting, it can be used to adjust to a desired value on the neutral side, neutralization, or acidic side while monitoring the pH of the alkaline object.

When a certain amount of raw water is passed through the strongly acidic cation exchange resin, the ability to produce acidic treated water 50 is lost, and the raw water comes out as it is as treated water.
This limit point can be grasped by monitoring the pH of the treated water 50 with a pH meter 93 in FIG. 2, as shown in step 4 of stage 1 in FIG.
Referring to Stage 2 (Cation Exchange Resin Regeneration) in FIG. 1, a strongly acidic cation exchange resin that has reached the limit point can be regenerated by using chemicals such as HCl (hydrochloric acid), H2SO4 (sulfuric acid), and can be used repeatedly. .

That is, in stage 2, in step 5 (regeneration line), the valves 1, 7, 3, 6 of FIG. 2 are opened, and the remaining raw water is discharged to the drain pits 95, 96.
In step 6 (sedation), all the valves 1 to 10 are closed, and then in step 7 (medication line), valves 1, 2, 8, 9, 3, 4, 10 are opened, and valves 6, 7, 5 are opened. close.
In the final step 7, a strong acid for injection (HCl or H ₂ SO ₄ ) 30 is injected into the cation exchange column 20 through the valves 8 and 9 and the ejector (suction valve) 91, and the strongly acidic cation exchange resin 22 is injected. Play.

  In this way, it is possible to omit a dangerous dilution operation with exothermic heat as compared with a case where strong acid for pouring as a powerful drug is directly diluted on site to obtain acidic water having a desired pH.

  After step 6, the cation exchange column 20 is replaced with a spare new product (recycled product), the used cation exchange column is brought back, and step 7 is carried out in a specialized factory. The dangerous work of handling can be omitted.

  3 and 4 are diagrams for explaining a method for producing alkaline water according to a second embodiment of the present invention. FIG. 3 is a flowchart, and FIG. 4 is a schematic diagram of a corresponding apparatus.

In FIG. 4, the anion exchange column 21 containing a strong alkaline anion (anion) exchange resin 23 that is not used or is being used is passed through the stage 2 of FIG. 3 described later, that is, chemicals such as NaOH (caustic soda). When chemicals are used, anions such as Cl ⁻ , NO ₃ ⁻ , SO ₄ ²⁻ , HCO ₃ ⁻ , etc. bound to the strongly alkaline anion exchange resin are replaced with OH ⁻ ions. A certain OH ^- ion can be electrodeposited onto a strongly alkaline anion exchange resin, and the anion exchange tower can be made into a recycled product equivalent to a new product.

The pH of make-up water in a normal field such as city water, well water, industrial water, middle water, seawater, etc. is about 6-8.
However, seawater is not practical in general since the ion exchange capacity of the ion exchange resin is lost immediately unless actually diluted with other make-up water, for example.
However, for example, replenishing water mixed with seawater, such as washing, washing and drainage of objects immersed in seawater, can be used as raw water in this embodiment.

In FIG. 4, this makeup water is designated as raw water 40.
As shown in stage 1 (raw water treatment) of FIG. 3, in step 1, a new or regenerated anion exchange tower is set, and in step 2, valves 1, 2, 3, 4, 5 of FIG. Close 6, 7, 8, 9, 10.
Then, in FIG. 4, raw water 40 is supplied to the anion exchange column 21, and chemical injection strong alkali (NaOH) 31 is not supplied to the anion exchange column 21, so that only the raw water is converted into a strong alkaline anion exchange resin, for example, a water passage speed. Water is passed at LV20m / hour.

OH in which the anions such as Cl ⁻ , NO ₃ ⁻ , SO ₄ ²⁻ , HCO ₃ ⁻ , etc., which were contained in the form of neutral salts or acids in the raw water, were electrodeposited on the strongly alkaline anion resin ^- replacing (hydroxide ion), the treated water after passing water OH ^- is, ^Cl was contained in the form of a neutral salt _{^{-, NO 3 -, SO 4}} 2-, HCO 3 -, etc. It increases by an amount roughly corresponding to the charge equivalent of the anion.

As a result, the treated water that has passed through the water collecting plate 24 becomes alkaline regardless of the pH of the raw water, and the pH of the treated water 51 is, for example, a standard strongly acidic anion exchange resin when monitored by a pH meter 93. In the case of a styrene-DVB copolymer having a quaternary ammonium group (—N (CH ₂ ) ₂ .OH) as an ion exchange group, 10.5 to 11.2 is shown.

The OH ⁻ ions in the produced treated water 51 exist stably, for example, pH = 10.5 after 6 months from the date of production, pH = 9.8 after one year, and pH slightly changes with time. There is a feature.

The pH is slightly decreased with elapsed time of the processed water and the oxygen O ₂ in the atmosphere HCO3 ^- result of the reaction of a base, by the CO ₂ is gradually vaporized, because alkalinity is reduced.
Thus, the treated water 51 once produced exhibits alkalinity and its pH is stable.

Referring to step 3A of stage 1 in FIG. 3, for the purpose of cleaning, an object containing an acid-insoluble substance attached to the surface of oil or metal or the like is immersed in treated water 51 or treated in the object. When the spent water is sprayed, OH ⁻ starts to react with the organic substance or the acid-insoluble substance.
As a result of the above reaction, fats and oils are decomposed, and acid-insoluble substances are decomposed and dissolved in treated water, and a degreasing phenomenon occurs.

  As an example, when the printed circuit board normally used in the treated water of pH = 11.2 is introduced and the observation is continued for 3 hours to 6 hours to 12 hours, the surface of the printed circuit board is within the range that can be confirmed visually. The pH of the treated water 51 was changed as follows.

After 3 hours, stains on the surface of the printed circuit board (organic matter containing soldering oil) gradually peeled off, and the pH at that time was 10.2.
After the elapse of 6 hours, about 60% of the entire surface of the printed board was soiled (organic matter), and the pH at that time was 9.5.
After 12 hours, 98% of the entire surface of the printed circuit board was soiled (organic matter), and the pH at that time was 8.1.

In consideration of this, alkaline water having pH = 11.2 reacted with an organic substance or the like attached to the metal surface to decompose the organic substance, so that the organic substance was peeled from the coin.
As proof, the pH of the treated water gradually increased and decreased, that is, the alkalinity of the treated water decreased as the decomposition of organic matter progressed.

When the final pH of the treated water 51 reaches the standard pH range of the wastewater of the country and each prefecture, there is no problem even if it is discharged as it is.
Conventionally, chlorofluorocarbons are often used for degreasing printed circuit boards and the like, and isopropyl alcohol has been the mainstream to suppress environmental problems. However, the treated water 51 should be an inexpensive alternative. Can do.

  Referring to step 3B of stage 1 in FIG. 3, for the purpose of pH adjustment, alkaline treated water 51 produced as described above is used for pH adjustment of objects such as soil, waste (waste) water, cement, and mortar. In this case, it can be used when it is desired to adjust to a desired value on the neutral side, neutralization, or alkaline side while monitoring the pH of the acidic object.

  For example, it is possible to improve the soil quality of acidic soil and neutralize waste (waste) water by using makeup water on site without preparing special chemicals.

Further, when the cement is solidified, it is necessary to react calcium oxide CaO with water H ₂ O to change to calcium hydroxide Ca (OH) ₂ .
In the past, seawater containing Cl ^- ions has been used as a catalyst for this coagulation reaction. However, it cannot be generally used because it causes corrosion of reinforcing bars.

In the alkaline treated water according to the present invention, the hydroxyl group OH ⁻ replaces Cl ⁻ as a catalyst for cement solidification, suppresses the cathode reaction that causes corrosion of the reinforcing bar, and always performs the anode reaction. Corrosion can be prevented and solidification can be improved.
Furthermore, since Cl ⁻ adhering to the surface of sand, gravel, etc. containing seawater or the like is simultaneously washed and neutralized, it is possible to prevent hardness deterioration after solidification.

When a strong alkaline anion exchange resin passes a certain amount of raw water, the ability to produce alkaline treated water is lost, and the raw water comes out as treated water as it is.
This limit point can be grasped by monitoring the pH of the treated water 51 with a pH meter 93 in FIG. 4 as shown in step 4 of stage 1 in FIG.
Referring to stage 2 (anion exchange resin regeneration) in FIG. 3, a strongly alkaline anion exchange resin that has reached the limit point can be regenerated by using a chemical such as NaOH (caustic soda) and can be used repeatedly.

That is, in stage 2, in step 5 (regeneration line), the valves 1, 7, 3, 6 of FIG. 4 are opened, and the remaining raw water is discharged to the drain pits 95, 96.
In step 6 (sedation), all the valves 1 to 10 are closed, and then in step 7 (medication line), valves 1, 2, 8, 9, 3, 4, 10 are opened, and valves 6, 7, 5 are opened. close.
In the final step 7, a strong alkali (NaOH) 31 for chemical injection is injected into the anion exchange tower 21 through the valves 8 and 9 and the ejector (suction valve) 91 to regenerate the strong alkaline anion resin 23.

  In this way, it is possible to omit a dangerous diluting operation accompanied by heat generation as compared with the case of directly diluting a strong alkali for drug injection, which is a powerful drug, to obtain alkaline water having a desired pH.

  After step 6 is completed, the anion exchange tower 21 is replaced with a spare new one (recycled product), the used anion exchange tower is brought back, and step 7 is carried out in a specialized factory. The dangerous work of handling in can be omitted.

It is a flowchart in 1st Example by this invention. FIG. 2 is a schematic view of a corresponding device in the first embodiment according to the present invention. It is a flowchart in 2nd Example by this invention. FIG. 6 is a schematic view of a corresponding apparatus in the second embodiment according to the present invention.

Explanation of symbols

1, 2, 3, 4, 5, 6, 7, 8, 9, 10 Valve (valve)
20 Cation (Cation) Exchange Tower 21 Anion (Anion) Exchange Tower 22 Strong Acid Cation Exchange Resin 23 Strong Alkaline Anion Exchange Resin 24 Water Collection Plate 30 Chemical Injection Strong Acid (HCl or H ₂ SO ₄ )
31 Strong alkali (NaOH) for chemical injection
40 Raw water 50, 51 Treated water 91 Ejector (suction valve)
93 pH meter 95, 96 Drainage pit

Claims (2)

Setting a new or renewed portable cation (cation) exchange tower;
Supplying a raw water having a pH of 6 or more and 8 or less to the cation exchange column by opening and closing a predetermined valve;
Using acidic treated water obtained from the cation exchange column for washing or pH adjustment;
Determining the pH of the treated water;
When the pH value of the treated water is out of a specified range, a plurality of steps of opening and closing a predetermined valve and supplying a strong acid for chemical injection to the cation exchange column to regenerate the function of the cation exchange column;
The manufacturing method of acidic water characterized by including. Setting a new or renewed portable anion (anion) exchange tower;
Supplying a raw water having a pH of 6 or more and 8 or less to the anion exchange column by opening and closing a predetermined valve;
Using alkaline treated water obtained from the anion exchange column for washing or pH adjustment;
Determining the pH of the treated water;
When the pH value of the treated water is outside the specified range, a plurality of steps for opening and closing a predetermined valve and supplying a strong alkali for chemical injection to the anion exchange column to regenerate the function of the anion exchange column;
The manufacturing method of alkaline water characterized by including.

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