FR3055894A1 - METHOD AND SYSTEM FOR ELECTROLYTIC TREATMENT OF WATER IN A BASIN. - Google Patents

Abstract

A method of treatment by electrolysis of the water of a pond (B), in particular of a swimming pool, the method comprising a step of electrolysis of the salt water of the pond (B), at a determined production rate in order to produce chlorine in said water, a step of measuring a UV index corresponding to the ultraviolet to which the water of the pond (B) is subjected and a step of modifying said production rate of the electrolysis as a function of the UV index measured to regulate the concentration of chlorine in the pond (B).

Description

GENERAL TECHNICAL AREA AND PRIOR ART

The present invention relates to the field of treatment by electrolysis of the water of a pool, in particular, of a swimming pool.

As is known, the water in a swimming pool must be kept clean and healthy so that users can safely benefit from clear bathing water, free from bacteria and microorganisms. In a known manner, chlorine has historically known and recognized disinfecting properties. To generate a regular production of chlorine by electrolysis, the pool water is first salted, then under the action of an electrolyser through which the pool water circulates, the salt molecules separate and release l hypochlorous acid, more commonly known as chlorine.

In known manner, the excess of chlorine is harmful to the health of bathers and to the environment, it can in particular lead to corrosion of equipment of the basin, in particular the coating covering the bottom and the sides of the basin known from the skilled person under the designation of "liner".

Is known in the prior art, from patent application WO 2011/131699 A1, a swimming pool water treatment system by electrolysis, the production of which is regulated as a function of several parameters measured by sensors, for example, a pH sensor, a redox potential sensor or a water and / or air temperature sensor. In practice, such a system does not make it possible to optimally regulate the production of chlorine and equipment of the basin can be damaged, which has a significant drawback. In particular, damage is likely to occur when the pool is covered.

The purpose of the invention is therefore to remedy these drawbacks by proposing a new method of treatment by electrolysis which can protect the equipment of the basin in an optimal manner.

GENERAL PRESENTATION OF THE INVENTION

The invention relates to a method of treatment by electrolysis of the water of a basin, in particular of a swimming pool, the method comprises a stage of electrolysis of the salt water of the basin, at a determined production rate, in order to produce chlorine in said water.

The method is remarkable in that it further comprises a step of measuring a UV index corresponding to the ultraviolet rays to which the water in the basin is subjected and a step of modifying said rate of production of electrolysis as a function of the UV index measured to regulate the concentration of chlorine in the pool.

The Applicant has conducted research in order to understand the role of the sun on the destruction of chlorine. Salt water contains NaCI salt molecules which by electrolysis separate into Na + and Cl- ions, which releases hypochlorous acid HCLO, i.e. chlorine, into the water in order to disinfect it. . The salt molecule recombines under the effect of UV radiation. During her research, the Applicant realized that the more intense the ultraviolet radiation, the shorter the recombination time of the molecule, and vice versa. By enslaving the electrolysis step to a measurement of the UV index, the production of chlorine makes it possible to optimally compensate for the destruction of the chlorine, that is to say, its recombination into a salt molecule.

Thanks to the invention, an optimal quantity of chlorine is maintained in the basin in order to allow its disinfection by eliminating the risk of damage to the equipment of the basin. Advantageously, the amount of chlorine is reduced compared to the prior art, which improves the quality of bathing and reduces the cost of treatment.

Unlike the methods according to the prior art which aimed to directly measure the chlorine in the basin water by amperometry or by measuring the redox couple of the water in order to control the chlorine production stage, the Applicant went to against known practices in order to seek an indirect way of enslavement by measuring ultraviolet rays and thus correct the faults of the previous methods. The prejudice that only one parameter of the pond water must be measured to control an electrolyser has thus been overcome.

According to one aspect of the invention, the rate of production of electrolysis is increased if the UV index is equal to or greater than 7. Thus, when ultraviolet radiation becomes very active for salt recombination, the production of chlorine is advantageously increased.

According to another aspect of the invention, the rate of production of electrolysis is lowered if the UV index is equal to or less than 1. For example, during the night or when the pool is covered (cover, tarpaulin, curtain, etc.) and prevents the passage of ultraviolet light, chlorine is very present because it does not recombine into a salt molecule. Thanks to the invention, any superfluous production of chlorine is advantageously avoided. This is particularly advantageous when the pool is covered during the winter and the electrolyser remains on. The risk of damaging the covered pool is advantageously eliminated. Preferably, the electrolysis is stopped or greatly reduced if the UV index is equal to or less than 1.

Preferably, the rate of production of electrolysis is modified in stages. A modification in stages is simple to implement and makes it possible to define rates according to a few specific types of sunshine. Preferably, the production rate can be modified according to at least three levels to correspond to a cover of the basin, standard use and strong sunshine.

Preferably, the method comprises a step of measuring the redox potential and a step of modifying said rate of production of electrolysis as a function of the redox potential measured in order to regulate the concentration of chlorine precisely.

Advantageously, the method according to the present invention makes it possible to take advantage of the controls by measuring the redox potential while correcting its imperfections. Thus, a servo error can be corrected by measuring the UV index which makes it possible to guarantee a stable amount of chlorine for any sunshine configuration.

Preferably, the rate of production of the electrolysis obtained as a function of the measured redox potential is modified if the UV index is equal to or greater than 7.

Thus, when the destruction of chlorine by ultraviolet radiation becomes too great, the rate of production of electrolysis is controlled as a function of the UV index, which makes it possible to rapidly and reactively increase production by comparison with a regulation according to the measured redox potential. In addition, when the UV index is equal to or less than 7, the regulation according to the measured redox potential is more precise than a regulation according to the UV index. Thanks to the invention, there is an advantage of the two regulations to optimally regulate the amount of chlorine.

Preferably, when the UV index is equal to or greater than 7, the production rate determined as a function of the measured redox potential is increased by a value depending on the UV index measured. Thus, the production rate is increased rapidly and reactively in order to compensate for the destruction by ultraviolet radiation.

The invention further relates to a system for the treatment by electrolysis of the water of a basin, in particular a swimming pool, the system comprising at least one electrolyser adapted to be fluidly connected to the basin and configured to produce chlorine from salt water from the basin.

The invention is remarkable in that the system includes means for measuring ultraviolet light configured to measure a UV index corresponding to the ultraviolet rays to which the water in the basin is subjected and management means configured to modify the rate of production of the electrolyser according to said UV index in order to regulate the concentration of chlorine in the basin.

The addition of ultraviolet measurement and management means makes it possible to optimally control the electrolyser so as to maintain a stable amount of chlorine in the basin. Advantageously, the ultraviolet measurement means and the management means can be easily added to a processing system according to the prior art to improve its capacities.

Preferably, the system comprises a module for measuring the redox potential capable of measuring the redox potential of the water in the basin, the management means are configured to modify the production rate of the electrolyser as a function of said measured redox potential. Thus, the ultraviolet measurement means and the management means work in synergy with an electrolyser which is slaved to a measurement of the redox potential so as to correct the faults.

Preferably, the management means are connected to the ultraviolet measurement means wirelessly. Thus, the means for measuring ultraviolet light can be placed independently near or in the basin.

According to a preferred aspect, the ultraviolet measurement means are in the form of an autonomous module, preferably capable of being placed in the basin. Such an ultraviolet measurement module can be conveniently placed in or near the basin, for example, on a terrace or the edge of the swimming pool.

According to a preferred aspect, the system further comprises a covering means capable of covering the basin and preventing the passage of ultraviolet. The ultraviolet measuring means are fixed to the covering means, preferably on an external face, that is to say facing towards the sun in the covering position, so as to measure the ultraviolet.

Preferably, the covering means is configured to mask the means for measuring ultraviolet in the storage position.

PRESENTATION OF THE FIGURES

The invention will be better understood on reading the description which follows, given solely by way of example, and referring to the appended drawings in which:

Figure 1 is a schematic representation of a processing system according to an embodiment of the invention;

FIG. 2A represents the evolution of the chlorine level in ppm in a basin subjected to ultraviolet rays during a summer day with an electrolyser operating constantly;

Ια Figure 2Β represents the evolution of the amount of chlorine in ppm in a basin subjected to ultraviolet during a summer day with an electrolyser slaved to an ultraviolet sensor;

FIG. 3 represents an example of modification of the chlorine production rate as a function of the UV index;

Figure 4 is a schematic representation of a processing system according to another embodiment of the invention with a module for measuring the redox potential;

FIG. 5A represents the change in the quantity of chlorine in ppm in a basin subjected to ultraviolet light during a summer day with an electrolyser controlled by a redox measurement module; and FIG. 5B represents the change in the amount of chlorine in ppm in a tank subjected to ultraviolet light during a summer day with an electrolyser controlled by a redox measurement module and an ultraviolet sensor.

It should be noted that the figures show the invention in detail to implement the invention, said figures can of course be used to better define the invention if necessary.

DESCRIPTION OF ONE OR MORE MODES OF IMPLEMENTATION AND IMPLEMENTATION

The invention will be presented for the treatment of the water in a swimming pool. Nevertheless, it goes without saying that the invention applies to any basin filled with water.

In order to conserve pure water in a swimming pool basin, it is known to treat swimming pool water with an electrolysis treatment system which is suitable for generating chlorine from the salt present in the water of the pool. swimming pool. To this end, the treatment system comprises an electrolyser known to the skilled person, in particular, by the patent application FR3018527A1 of the Applicant.

An electrolyser comprises a treatment enclosure, known to a person skilled in the art under the designation of vessel, in which is mounted an electrolytic cell supplied electrically with current. The electrolyser enclosure usually has an opening for the water to be treated and an opening for the outlet for treated water. Preferably, the amount of chlorine produced by the electrolyser can be advantageously adjusted. The production rate of an electrolyser is adjustable by the user as required. In practice, the TX production rate corresponds to the supply voltage of the electrodes of the electrolytic cell.

With reference to FIG. 1, there is shown a swimming pool B filled with salt water and a treatment system according to the invention which comprises:

an electrolyser 1 fluidly connected to the basin B and configured to produce chlorine from salt water, ultraviolet measuring means 2 placed in the swimming pool basin B and management means 3 configured to control the electrolyser 1 by function of the measurement of ultraviolet, in particular, of the UV index.

As will be presented in detail later, such a treatment system makes it possible to regulate the chlorine level, which makes it possible, on the one hand, to prevent the water quality from decreasing due to lack of chlorine and , on the other hand, that the basin equipment does not deteriorate due to excess chlorine.

With reference to FIG. 1, the electrolyser 1 is fluidly connected to the basin B by an upstream pipe 11 and a downstream pipe 12. When in use, the salt water of the tank B moves successively from the tank B, in the pipe upstream 11, in the electrolyser 1, in the downstream pipe 12 and in the basin B. The electrolyser 1 makes it possible to generate chlorine from salt water, which makes it possible to disinfect the water of basin B.

The Applicant has noticed that the destruction of chlorine depended on the sunshine of the basin B and, more particularly, of the ultraviolet rays received by said basin B. By slaving the production of chlorine to an ultraviolet measurement, it is advantageously possible to increase the production when the destruction of chlorine is important and lower the production of chlorine when the chlorine is not destroyed. This maintains a stable amount of chlorine in said basin B.

The electrolyser 1 having already been presented, the means for measuring ultraviolet 2 and the management means 3 will now be presented with reference to FIG. 1. The means for measuring ultraviolet 2 are positioned in the basin B or in its immediate vicinity so as to measure the UV index to which the water in the basin B is subjected. The ultraviolet measurement means 2 are functionally connected to the management means 3 which acts on the electrolyser 1, in particular on its TX production rate.

In this embodiment, the ultraviolet measuring means 2 are in the form of an ultraviolet sensor. Such an ultraviolet sensor is known, in particular, under the trade designation TOCON E2 5 Sglux. Such a sensor makes it possible in particular to detect ultraviolet rays between 200 nm and 390 nm with optimal detection at 297 nm. It goes without saying that other means of measurement may be suitable.

Preferably, the ultraviolet measuring means 2 are configured to measure a UV index as defined by standard CIE087 / DIN5050. As a reminder, the UV index corresponds to the integral according to the wavelength of the light power on the ground in watt / m2 / unit of wavelength) * 0.04 * erythematous action index. As a reminder, the erythematous action index is equal to 1 for wavelengths less than 300 nm, 0.1 for 310 nm, 0.01 for 320 nm and 0.001 for 330 nm.

The UV index is a function of the received light power. It goes without saying that electrolysis could be controlled as a function of said received light power.

In this example, the ultraviolet measuring means 2 are supplied autonomously, for example, in a photovoltaic manner, but it goes without saying that the supply could be different.

Preferably, the measuring means 2 are mounted in a support which can be arranged floating in the basin B or mounted in the basin, in particular, on a side wall.

Preferably, the management means 3 are in the form of a computer configured to modify the production rate TX of the electrolyser 1 as a function of the UV index measured.

Changing the TX production rate based on the UV index measured can be done in different ways. The modification can be, for example, proportional, by constant stages, by increasing stages (Figure 3) or other. In this example, the management means 3 are configured to modify the TX production rate according to 5 different stages represented in FIG. 3:

a first stage PI in which the TX production rate increases from 6% to 20% for a UV index varying from 0 to 1, a second stage P2 in which the TX production rate increases from 20% to 40% for a UV index varying from 1 to 7, a third level P3 in which the TX production rate is increasing from 40% to 66% for a UV index varying from 7 to 9, a fourth level P4 in which the TX production rate is increasing from 66% to 100% for a UV index varying from 9 to 11, and a fifth level P5 in which the TX production rate is constant at 100% for a UV index greater than 11.

These bearings P1-P5 are given by way of example and it goes without saying that they could be adapted as required.

The management means 3 are connected to the ultraviolet measurement means 2 wirelessly, in particular, by a bluetooth, LoRA or similar link. It goes without saying that communication could be different, in particular, wired.

In this example, the management means 3 are in the form of an independent module which is connected to the electrolyser 1 but it goes without saying that the management means 3 could be directly integrated into said electrolyser 1.

An example of implementation of the invention will now be presented with reference to FIGS. 2A and 2B.

As illustrated in FIGS. 2A and 2B, the UV index varies over time H. The ultraviolet rays are intense between 12h and 16h, that is to say, with an index greater than or equal to 7.

Referring to FIG. 2A, when the chlorinator 1 produces chlorine constantly, for example at a normal TX production rate, here equal to 60%, it is noted that the chlorine (in ppm) is destroyed significantly between 12h and 16h (strong salt recombination). As a result, the amount of chlorine is not sufficient, which affects the quality of the water in basin B. Similarly, after 6 p.m., in the absence of ultraviolet, the amount of chlorine becomes too large, which which can damage the equipment in basin B.

With reference to FIG. 2B, the evolution of the quantity of chlorine is shown when the electrolyser 1 is controlled by the ultraviolet measurement means 2. In this example of implementation, the management means 3 are configured to increase the TX production rate of the electrolyser 1 as a function of the UV index in stages. Thus, the TX production rate is less than 60% before 11 a.m. and after 4 p.m. (UV index less than 7 corresponding to the second stage P2). As little chlorine is destroyed, there is no need to produce more chlorine. On the contrary, between 11h and 16h, the TX production rate is greater than 70% since the UV index is between 7 and 9 (P3 level). The high production of chlorine makes it possible to compensate for its destruction by the ultraviolet rays.

Due to this enslavement, the amount of chlorine varies slightly over time, which is very advantageous.

Very advantageously, such a method makes it possible to lower or stop the production of chlorine when the UV index is very low for example, when the basin B is covered with a cover (with bubbles, bars, etc.) or a tarpaulin, a floating curtain, a shelter, etc. This avoids the production of chlorine when it is not destroyed by ultraviolet light, which prevents any deterioration of the coating of the basin or of said cover, tarpaulin or curtain.

According to another embodiment, the means for measuring ultraviolet are mounted on an external face of a cover, a tarpaulin or a curtain, that is to say, any means of closing said basin B which prevents the propagation of ultraviolet in the salt water of said basin B. In this case, the management means are configured opposite to the first embodiment so as to decrease the production of chlorine when the UV index increases.

In fact, when the covering means is placed on the basin, the measuring means detect ultraviolet light since the measuring means are placed on the external face of said covering means in the covering position.

On the contrary, when the covering means is in the storage position, the ultraviolet measuring means do not detect ultraviolet since the covering means is rolled or folded without being exposed to light. Preferably, the ultraviolet measuring means are directly integrated into said covering means. However, it goes without saying that they could be attached to it, in particular, removably.

Another embodiment of a processing system according to the invention is shown in Figure 4. For the sake of clarity and conciseness, only the differences between the two embodiments will now be presented.

As illustrated in FIG. 4, the treatment system further comprises a redox measurement module 4 which is adapted to measure the redox potential of the water in the basin B, in particular in the upstream pipe il of the 'electrolyser 1, and compare it to a redox setpoint. If the measured redox potential is lower than the setpoint, the rate of electrolysis production is increased. Such a redox measurement module is known to those skilled in the art and will not be presented in detail. The redox measurement module 4 can be connected directly to the electrolyser 1 or to the management means 3.

In theory, a redox measurement measures the amount of chlorine in the water. In practice, the correlation between redox measurement and quantity of chlorine is imperfect. Also, attempts to enslave electrolyser 1 to a redox measurement module 4 are not optimal.

By way of example, with reference to FIG. 5A, to control an electrolyzer 1 to a redox measurement, the electrolyser 1 is activated at a TX production rate of 45% as soon as the redox measurement is less than a predetermined Credox setpoint. , here, equal to 750mV. As a result, the amount of chlorine varies greatly, which has the aforementioned drawbacks. In addition, the redox measurement obtained is sometimes erroneous, which increases said drawbacks.

With reference to FIG. 5B, there is shown in dotted lines a proportional redox control and in solid line a redox and UV control of the electrolyser. When the UV index is less than 7, before 11 a.m. and after 3 p.m., the amount of chlorine is regulated as a function of the measured redox potential, which makes it possible to precisely monitor variations in the amount of chlorine.

When the UV index is equal to or greater than 7, between 11 a.m. and 3 p.m., the production rate determined according to the measured redox potential is increased by a value depending on the measured UV index. With reference to FIG. 5B, the combined production rate (TX redox + uv) can be 10 to 20% higher compared to the production rate depending on the redox (Tredox).

Note in FIG. 5B that the servo-control by measurement of ultraviolet rays makes it possible to correct an imperfect redox measurement, in particular, over the range of high UV index. Thanks to the invention, the electrolyser 1 is controlled, on the one hand, by the redox measurement module 4 and, on the other hand, by the ultraviolet measurement means 2. Such an embodiment makes it possible to obtain an amount of chlorine which varies very slightly over time.

It goes without saying that other parameters could be added to improve the control of the electrolyzer 1, in particular, a measurement of the water temperature, the measurement of the pH, a measurement of the chlorine stabilizer, etc.

Claims (11)

1. Method of treatment by electrolysis of the water of a basin (B), in particular of a swimming pool, the method comprising a step of electrolysis of the salt water of the basin (B), at a production rate determined, in order to produce chlorine in said water, method characterized by the fact that it further comprises a step of measuring a UV index corresponding to the ultraviolet rays to which the water in the basin is subjected (B) and a step of modifying said electrolysis production rate as a function of the UV index measured in order to regulate the concentration of chlorine in the basin (B). 2. Method according to claim 1, in which the rate of production of electrolysis is increased if the UV index is equal to or greater than 7. 3. Method according to one of claims 1 and 2, wherein the rate of production of electrolysis is lowered if the UV index is less than 1. 4. Method according to one of claims 1 to 3, wherein the rate of production of electrolysis is changed in stages. 5. Method according to one of claims 1 to 4, comprising a step of measuring the redox potential and a step of modifying said rate of production of electrolysis as a function of the redox potential measured in order to regulate the chlorine concentration optimally . 6. Method according to claim 5, in which the rate of production of the electrolysis obtained as a function of the measured redox potential is modified if the UV index is equal to or greater than 7. 7. System for treatment by electrolysis of the water of a basin (B), in particular a swimming pool, the system comprising at least one electrolyser (1) adapted to be fluidly connected to the basin (B) and configured to produce chlorine from salt water in the basin (B) according to a production rate, system characterized in that it comprises means for measuring ultraviolet (2) configured to measure a UV index corresponding to the ultraviolet to which the pond water (B) and management means (3) configured to modify the production rate of the electrolyzer (1) as a function of said UV index in order to regulate the chlorine concentration in the pond (B). 8. The system as claimed in claim 7, comprising a module for measuring the redox potential (4) capable of measuring the redox potential of the water in the basin (B), the management means (3) are configured to modify the production rate of the electrolyser (1) as a function of said measured redox potential. 9. System according to one of claims 7 and 8, wherein the management means (3) are connected to the ultraviolet measuring means (2) wirelessly. 10. System according to one of claims 7 to 9, in which the measuring means 15 of ultraviolet (2) are in the form of an autonomous module, preferably, able to be arranged in the basin (B). 1/5