WO1998034579A1

WO1998034579A1 - Method of manufacturing carbonated spring

Info

Publication number: WO1998034579A1
Application number: PCT/JP1998/000458
Authority: WO
Inventors: Makoto Uchida; Masanao Kobuke; Kenji Watari; Yoshinori Nagasaka
Original assignee: Mitsubishi Rayon Co., Ltd.; Mitsubishi Rayon Engineering Co., Ltd.
Priority date: 1997-02-05
Filing date: 1998-02-04
Publication date: 1998-08-13
Also published as: EP0968699A4; DE69807851T2; EP0968699A1; EP0968699B1; DE69807851D1; AU5779698A

Abstract

A method of manufacturing a carbonated spring by supplying a carbon dioxide to a carbon dioxide dissolver and dissolving the carbon dioxide in raw water, which comprises measuring the pH of the carbonated spring generated, calculating carbon dioxide concentration data of the carbonated spring generated from the pH measurement and an alkalinity of the raw water, and regulating an amount of carbon dioxide supplied to the carbon dioxide dissolver so that the carbon dioxide concentration data amounts to a preset target carbon dioxide concentration. According to the method, it is possible so simply manufacture the carbonated spring of a target concentration using an inexpensive pH measuring device.

Description

Manufacturing method of carbonic acid springs Technical field

The present invention relates to a method for producing a carbonated spring in which a physiologically effective carbonated spring can be easily obtained at home or the like as a carbonated spring having a predetermined carbon dioxide gas concentration.

Background technology

Carbonated springs have been used in hot springs and other public baths for a long time because of their excellent thermal insulation. It is considered that the warming action of the carbonated spring is basically because the body environment is improved by the peripheral vasodilation of the carbon dioxide contained. In addition, the percutaneous invasion of carbon dioxide causes an increase and expansion of the capillary bed and improves blood circulation in the skin. Therefore, it is said to be effective in treating regressive lesions and peripheral circulatory disorders.

Because of the excellent properties of carbonated springs, attempts have been made to artificially mix them. For example, carbonated springs are obtained by methods such as sending carbon dioxide gas into the bathtub in the form of bubbles, a chemical method of reacting carbonates and acids, and a method of pressurizing hot water and carbon dioxide gas in a tank for a certain period of time. Was. In addition, Japanese Patent Application Laid-Open No. 2-27959-58 proposes a method in which carbon dioxide gas is supplied through a hollow fiber semipermeable membrane and absorbed in water.

There is no known commercially available carbonated spring manufacturing equipment that measures and controls the concentration of carbon dioxide in the carbonated spring. This is partly due to the fact that it is used in a region with relatively low carbon dioxide concentration, for example, in the range of 100 to 140 ppm. However, the effect of carbonated springs differs slightly depending on the concentration of carbon dioxide gas, so there are cases where a slightly higher concentration of carbonated spring or a lower concentration of carbonated spring is desired. Several devices have been known for measuring the concentration of carbon dioxide dissolved in water. The flow-type carbon dioxide gas meter is composed of a carbon dioxide gas electrode and a carbon dioxide gas concentration indicator, but the diaphragm of the electrode and the internal liquid must be replaced every one to three months. Since it is somewhat expensive, it is not practical as a measuring device used in a carbonated spring manufacturing device. It is also used in carbonated beverage production equipment. Thermal conductivity detection type carbon dioxide concentration meters, such as those used, are extremely expensive and are not suitable for measuring the concentration of carbonated springs.

To keep the concentration of carbon dioxide in the bathtub constant, a method of installing a PH sensor in the bathtub and adjusting the supply amount of carbon dioxide to the carbon dioxide dissolver is disclosed in Japanese Patent Application Laid-Open No. Hei 8-2-152770. It is known, however, that there is not always a unique relationship between the pH of the carbonated spring in the bathtub and the concentration of carbon dioxide gas due to impurities dissolved in the carbonated spring in the bathtub or the quality of the raw water. Therefore, it is difficult to set the carbon dioxide concentration in the bathtub to a specific target value by this method.

Disclosure of the invention

An object of the present invention is to provide a method for easily producing a carbonated spring having a specific concentration at home or the like. ,

That is, the present invention relates to a method for producing a carbonated spring by supplying carbon dioxide gas to a carbon dioxide gas dissolving unit and dissolving the carbon dioxide gas in raw water, wherein the pH of the carbonated spring generated by the carbon dioxide dissolving unit is measured. Calculates the carbon dioxide gas concentration data of the carbonated spring generated from the value of the raw water and the value of the raw water power, and calculates the carbon dioxide gas to the carbon dioxide dissolver so that the carbon dioxide gas concentration data becomes the preset target carbon dioxide gas concentration value. This is a method for producing a carbonated spring characterized by adjusting the gas supply.

Brief explanation of drawings

FIG. 1 is a flow sheet showing an example of an apparatus used in the method for producing a carbonated spring of the present invention, and FIG. 2 is a graph showing the relationship between the concentration of carbon dioxide in the carbonated spring, pH, and alkalinity of raw water. FIG. 3 is a schematic diagram of a three-layer composite hollow fiber membrane preferably used in the method for producing a carbonated spring of the present invention, and FIG. 4 is another diagram of the apparatus used in the method for producing a carbonated spring of the present invention. It is a flow sheet showing an example.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in more detail with reference to the drawings.

FIG. 1 is an example of a flow sheet showing a method for producing a carbonated spring according to the present invention. Hot water obtained by heating raw water such as tap water is stored in a hot water tank 3 via a motor-operated valve 1 and a pre-filter 2, from which the water pump 4 traps debris in the hot water. Guided to vessel 6. Carbon dioxide gas is a carbon dioxide gas cylinder From 7, the gas is supplied to the carbon dioxide dissolver via a pressure reducing valve 8, an on-off valve 9 and a control valve 10 as a carbon dioxide gas supply amount adjusting means. The carbon dioxide gas dissolver used in this example is configured with a built-in membrane module provided with a hollow fiber membrane, and the carbon dioxide gas is guided to the outer surface of the hollow fiber membrane in the dissolver. Raw water flowing through the hollow part of the hollow fiber membrane comes into contact with the raw fiber through the membrane surface of the hollow fiber membrane and dissolves in the raw water. The raw water becomes a carbonated spring and is discharged from the carbon dioxide gas dissolver.

By using a carbon dioxide dissolver with a membrane module to dissolve carbon dioxide through the membrane surface, the gas-liquid contact area can be increased and the carbon gas can be dissolved with high efficiency. Can be. As such a membrane module, a hollow fiber membrane module, a flat membrane module, a spiral type module and the like can be used. Above all, the hollow fiber membrane module can dissolve carbon dioxide gas with the highest efficiency. The pH of the carbonated spring generated by the carbon dioxide dissolver in this way is measured by the pH sensor 11. The concentration of carbon dioxide in the carbonated spring and the pH of the carbonated spring have a certain relationship, but the concentration of carbon dioxide in the carbonated spring cannot be uniquely determined from the pH value. In other words, as shown in Fig. 2, the relationship between the concentration of carbon dioxide and the pH of the carbonated spring changes significantly depending on the alkalinity of the raw water. For this reason, in the method of the present invention, the PH value of the generated carbonated spring measured by the pH sensor and the value of the total power of the raw water are input to the computing unit, and the real power shown in FIG. Using the relationship between the temperature and the pH value, the concentration of carbon dioxide gas is calculated and output.

In general, if the raw water is water obtained from a constant water source such as tap water, the value of the raw water does not fluctuate so much over time. Therefore, once the carbonated spring production equipment is installed and put into operation, once the raw water power level is measured, that value can be used thereafter. Of course, each time the carbonated spring manufacturing equipment is used, the alkalinity of the raw water may be measured and the value may be input to the computing unit. Incidentally, alkalinity according to the present invention, OH @ - is included in the raw _{^{water, C 0 3 2 -, HC}} 0 3 - is one way to view the content of the component which consumes acid such as, p H 4.8 Adoption of alkalinity (M alkalinity) is preferred.

In the present invention, the carbon dioxide gas concentration data of the carbonated spring obtained by the calculation in this manner is input to the target carbon dioxide gas desired by the user in advance before the operation of the carbonated spring manufacturing apparatus is started. The amount of carbon dioxide supplied to the carbon dioxide dissolver is adjusted so that a carbon dioxide spring with the target carbon dioxide concentration is generated in comparison with the carbon dioxide concentration. Various methods can be used to adjust the gas supply amount. In the present embodiment, the gas flow amount control valve 10 is used. However, the gas supply amount can be adjusted by controlling the gas flow amount control valve.

It is preferable that the pH sensor is usually installed near the outlet of the carbon dioxide gas dissolver to eliminate the influence of a control disturbance factor. However, the measurement accuracy of the PH sensor decreases with time due to contamination by the liquid to be measured, regardless of the installation position, so it is preferable to perform calibration periodically. In particular, in order to suppress the error in the carbon dioxide concentration data to about several percent, it is necessary to keep the pH error measured by the pH sensor within ± 0.05. For this purpose, it is preferable that the pH sensor be calibrated once every one to two weeks.

To calibrate the pH sensor, first close the motor-operated valve 12 and motor-operated three-way valve 13 and open the motor-operated valve 14 to drain a part of the pH sensor holder liquid (carbonated spring). Close 14 and send the pH 4 standard solution from the standard solution tank 15 to the holder to fill it up and perform calibration at PH 4. After that, the valve 14 is opened to discharge the pH 4 standard solution from the holder section, then the valve 14 is closed and the PH 7 standard solution is sent from the standard solution tank 16 to a part of the holder. And calibrate at pH 7. Thus, the calibration of the PH sensor is completed by performing the calibration at two different pH values. At this time, it is preferable to provide solenoid valves 17 and 18 at the vent of the standard solution tank to shut off the outside air during normal times to prevent deterioration of the standard solution.

As the hollow fiber membrane used in the carbon dioxide gas dissolver 9, various kinds of hollow fiber membranes are used as long as they are excellent in gas permeability, and may be a porous membrane or a non-porous membrane. When a porous hollow fiber membrane is used, it is preferable that the diameter of the opening pores on the surface is ◦0.1 to 10 m. The most preferred hollow fiber membrane is a composite hollow fiber membrane having a three-layer structure i in which both sides of a thin non-porous layer are sandwiched between porous layers, and specific examples thereof include a three-layer composite membrane manufactured by Mitsubishi Rayon Co., Ltd. Hollow fiber membrane (MH F, trade name). FIG. 3 is a schematic diagram showing an example of such a composite hollow fiber membrane, where 19 is a non-porous layer and 20 is a porous layer. Here, the non-porous layer (membrane) is a membrane through which gas permeates by a dissolution / diffusion mechanism in the membrane substrate, and forms pores through which gas can permeate in gaseous form like a Knudsen flow. Any material may be used as long as it is not qualitatively included. By using a non-porous membrane, gas can be supplied and dissolved at any pressure without being released as bubbles into the carbonated spring, and it can be dissolved efficiently, and it can be easily dissolved at any concentration with good controllability. it can. Also, warm water, which is rarely generated in the case of a porous membrane, does not flow back to the gas supply side through the pores. The composite hollow fiber membrane having a three-layer structure is preferable because the non-porous layer is formed as an extremely thin film having excellent gas permeability, and is formed by being protected by the porous layer so as not to be easily damaged. In addition, since the amount of carbon dioxide released into the carbonated spring as bubbles is small, the pH can be measured with high accuracy.

The thickness of the hollow fiber membrane is preferably from 10 to 150 m. If it is less than 1 m, the strength of the membrane tends to be insufficient, and if it exceeds 150 m, the permeation rate of carbon dioxide gas decreases and the dissolution efficiency tends to decrease. In the case of a composite hollow fiber membrane having a three-layer structure, the thickness of the non-porous membrane is preferably 3 to 2 m. If the thickness is less than 0.3 im, the film is liable to be deteriorated, and if the film is deteriorated, a leak occurs. On the other hand, if it exceeds 2 m, the permeation rate of carbon dioxide gas will decrease and the dissolution efficiency will decrease.

Preferred examples of the hollow fiber membrane material include silicone-based, polyolefin-based, polyester-based, polyamide-based, polyimide-based, polysulfone-based, cellulose-based, and polyurethane-based membranes. Preferred materials for the non-porous membrane of the composite hollow fiber membrane having a three-layer structure include polyurethane, polyethylene, polypropylene, poly (4-methylpentene-11), polydimethylsiloxane, polyethylcellulose, and polyphenylene oxide. Polyurethane is particularly preferred because it has good film-forming properties and has a small amount of eluted substances.

The inner diameter of the hollow fiber membrane is preferably from 50 to 100 m. If it is less than 50 m, the flow resistance of the carbon dioxide gas flowing through the hollow fiber membrane becomes large, and it becomes difficult to supply the carbon dioxide gas. On the other hand, when the length exceeds 100 m, the size of the dissolver increases, and the size is not reduced. When a hollow fiber membrane is used in a carbon dioxide gas dissolver, a method in which carbon dioxide gas is supplied to the hollow side of the hollow fiber membrane and raw water is supplied to the outer surface side to dissolve the carbon dioxide gas, and an outer surface of the hollow fiber membrane There is a method in which carbon dioxide is supplied to the side and raw water is supplied to the hollow side to dissolve the carbon dioxide. When carbon dioxide gas is supplied to the outer surface of the hollow fiber membrane and raw water is supplied to the hollow side to dissolve carbon dioxide, the concentration of carbon dioxide in hot water becomes high regardless of the type of membrane module. Is preferred because it can be dissolved in

As the carbon dioxide gas dissolver used in the method of the present invention, a carbon dioxide gas dissolver having a diffuser means in which a diffuser made of a porous body is provided at the bottom in the carbon dioxide gas dissolver may be used. The material and shape of the porous body disposed in the air diffuser may be of any type, but the porosity, that is, the volume ratio of the voids present in the porous body itself to the entire porous body is It is preferably 5 to 70 V o 1%. In order to further enhance the dissolution efficiency of carbon dioxide gas, a lower porosity is more suitable, and preferably 5 to 40 V 01%. If the porosity exceeds 70 vo 1%, it becomes difficult to control the flow rate of the carbon dioxide gas. Bubbles become large and the dissolving efficiency tends to decrease. If the porosity is less than 5 vol 1%, the supply amount of carbon dioxide decreases, and the dissolution of carbon dioxide tends to take a long time.

The diameter of the opening on the surface of the porous body is preferably 0.01 to 10 m in order to control the flow rate of the diffused carbon dioxide gas and to form fine bubbles. If the pore size exceeds 1 Q / m, the bubbles rising in the water will be too large, and the dissolution efficiency of carbon dioxide will tend to decrease. On the other hand, if it is less than 0.01 m, the amount of air diffused into water decreases, and it tends to take a long time to obtain a high-concentration carbonated spring.

The larger the surface area of the porous body disposed in the diffuser part of the diffuser means, the more bubbles can be generated, and the contact between the carbon dioxide gas and the hot water proceeds efficiently and the dissolution before the bubbles are generated Therefore, the dissolution efficiency is increased. Therefore, although the shape of the porous body is not limited, those having a large surface area are preferable. There are various methods for increasing the surface area, such as making the porous body cylindrical, or making the shape like a flat plate to make the surface uneven, but using a porous hollow fiber membrane Preferably, it is particularly effective to use a bundle of a large number of porous hollow fiber membranes.

The material of the porous body includes various materials such as metal, ceramic, and plastic, but is not particularly limited. However, it is not preferable to use a hydrophilic material because hot water enters through the pores on the surface into the air diffuser when the supply of carbon dioxide gas is stopped.

FIG. 4 is an example of another flow sheet of the method for producing a carbonated spring of the present invention. In this example, hot water is supplied by the water pump 4 and the pressure tank 23 without a hot water tank. You. That is, when the terminal valve of the water supply destination of the carbonated spring is opened, hot water starts to flow, and this flow is detected by the flow switch 21 and the water supply pump 4 is automatically started. On the other hand, when the terminal valve is closed, the water pump 4 is still operating and the pressure in the piping rises, but the pressure tank 23 functions as a pressure buffer, and when the pressure reaches the predetermined upper limit, the pressure switch 2 2 works and the water pump 4 stops.

The carbon dioxide gas dissolver 6 having a built-in hollow fiber membrane and flowing hot water through the hollow portion of the hollow fiber membrane to dissolve the carbon dioxide gas in contact with the carbon dioxide gas is provided with a pipe 31 for backwashing. When warm water that has passed through the pre-filter flows into the hollow part of the hollow fiber membrane in the dissolver 6 for a long time, scale accumulates at the potting opening end of the hollow fiber membrane, which is the supply port to the hollow fiber membrane hollow part. It was found that the production flow rate gradually decreased. However, it has been found that this scale can be relatively easily removed by flowing the water flow in the carbon dioxide gas dissolver 6 in the opposite direction. That is, the solenoid valve 12 is closed, the on-off valve 25 is opened, and the three-way valve 24 is opened to the backflow washing pipe side to flow hot water in the hollow fiber membrane in the opposite direction. The reverse flow cleaning, 1 to 3 kg Z cm ² about normal water flow pressure 0. Be performed 5-3 and 0 minutes to flow, it depends but 1-4 weeks usage time of the carbon dioxide gas dissolver It is preferable to carry out the inspection about once. The use of a finer filter in the check filter in front of the carbon dioxide dissolver can also prevent the scale from adhering, but it is not practical because the pressure loss becomes too large.

The carbon dioxide dissolver 6 is provided with a drain vent at a portion communicating with the outside of the hollow fiber membrane, and the water vapor evaporated from the hollow part of the hollow fiber membrane is condensed and collected at the outside part of the hollow fiber membrane. Open the release valve 26 if necessary and discharge to the outside.

An overflow prevention valve 27 is provided upstream of the carbon dioxide gas flow control valve 1 ◦.If the carbon dioxide gas leaks for some reason and excess carbon dioxide gas flows, the overflow prevention valve 27 is Automatically shuts off, ensuring the safety of the carbonated spring manufacturing equipment.

A gas vent valve 28 is provided downstream of the carbon dioxide gas dissolving unit 6, and removes undissolved carbon dioxide gas bubbles contained in the produced carbonated spring and discharges it to a drain pipe. As the gas vent valve 28, the same one as that generally used for general hot water piping can be used. Since gaseous carbon dioxide is not easily absorbed percutaneously, there is no carbon dioxide spring effect on the human body.In addition, the gas vent valve is installed to reduce the concentration of carbon dioxide in the air in the bathroom. The position is valid. The other equipment in Fig. 4 is the same as in Fig. 1. Hereinafter, the present invention will be described specifically with reference to examples.

Example 1

A carbonated spring was manufactured using the flow sheet apparatus shown in FIG. As the carbon dioxide gas dissolver, the one incorporating the above-mentioned three-layer composite hollow fiber membrane MHF with an effective total membrane area of 2.4 m ² was used.

Warm water obtained by heating tap water having an M alkalinity of 16.0 to 40 ° C. was supplied to a carbon dioxide gas dissolver at 10 liters Zmin. The target carbon dioxide concentration of the carbonated spring was set to 600 ppm, the pH of the carbonated spring obtained by the carbon dioxide dissolver was detected by the pH sensor, and the CPU based on this and the M alkalinity value of the tap water The carbon dioxide gas concentration data was obtained by calculation, and the carbon dioxide gas was supplied to the carbon dioxide gas dissolver by controlling the opening of the carbon dioxide gas flow control valve so that the carbon dioxide gas concentration data matched the target carbon dioxide gas concentration. As a result, the carbon dioxide gas concentration of the carbonated spring obtained 4 minutes after the start of operation was measured. As a result, it was found to be 615 ppm, and a carbonated spring approximately equivalent to the target carbon dioxide gas concentration was generated. The carbon dioxide concentration was measured with an ion meter IM 40S carbon dioxide electrode CE-235 made by Toa Denpa Kogyo.

Industrial applicability

ADVANTAGE OF THE INVENTION According to the manufacturing method of the carbonated spring of this invention, the carbonated spring of the target carbon dioxide concentration can be easily manufactured at home etc. using a relatively inexpensive PH measuring device.

Claims

The scope of the claims

1. In the method of producing carbon dioxide spring by supplying carbon dioxide gas to carbon dioxide gas dissolver and dissolving carbon dioxide gas in raw water, the PH of carbonate spring generated by carbon dioxide gas dissolver is measured, and the PH measurement value and raw water Calculate the carbon dioxide gas concentration data of the carbonated spring generated from the value of the degree of carbon dioxide and calculate the amount of carbon dioxide gas supplied to the carbon dioxide dissolver so that the carbon dioxide gas concentration data becomes a preset target carbon dioxide gas concentration value. A method for producing a carbonated spring characterized by adjusting.

2. The method for producing a carbonated spring according to claim 1, wherein a carbon dioxide gas dissolver provided with the membrane module is used.

3. The method for producing a carbonated spring according to claim 2, wherein a membrane module provided with a hollow fiber membrane is used.

4. The method for producing a carbonated spring according to claim 3, wherein a carbon dioxide gas is supplied to the outer surface side of the hollow fiber membrane, and raw water is supplied to the hollow side to dissolve the carbon dioxide gas.

5. The method for producing a carbonated spring according to claim 3 or 4, wherein a hollow fiber membrane having an inner diameter of 500 to 1000 µm is used.

6. The method for producing a carbonated spring according to claim 3, 4 or 5, wherein a hollow fiber membrane having a thickness of 10 to 150 m is used.

7. The method for producing a carbonated spring according to any one of claims 3 to 6, wherein a composite hollow fiber membrane having a three-layer structure in which both sides of a thin non-porous layer are sandwiched between porous layers is used.

8. The method for producing a carbonated spring according to claim 7, wherein a hollow fiber membrane having a nonporous layer thickness of 3 to 2 m is used.

9. The method for producing a carbonated spring according to claim 7, wherein the non-porous layer uses a composite hollow fiber membrane made of polyurethane.

10. The method for producing a carbonated spring according to claim 1, wherein the diffuser portion made of a porous body uses a carbon dioxide gas dissolver having an air diffuser provided at the bottom of the carbon dioxide gas dissolver.

11. The method for producing a carbonated spring according to claim 10, wherein the porosity of the porous body is 5 to 70 Vo1%, and the diameter of the open pores on the surface is 0.01 to 10 m.

12. The method for producing a carbonated spring according to claim 10, wherein the porous body is a porous hollow fiber membrane.