RU2088539C1 - Apparatus for producing detergent and disinfecting solutions - Google Patents

Abstract

FIELD: water treatment. SUBSTANCE: invention relates to equipment for electrochemical water treatment and may also be used for producing detergent and disinfecting solutions. Apparatus comprises at least one electrochemical cell equipped with vertical coaxial cylindrical and rod-type electrodes installed in dielectric bushings. There is also coaxial ceramic ultrafiltration diaphragm installed in bushings between electrodes and separating interelectrode space into electrode chambers. Solution being treated enters and comes out of electrode chambers through channels available in lower and upper bushings, respectively. Apparatus includes power source with its positive and negative poles connected with electrodes. Solution-supply line is bound to anode chamber, outlet of the latter being connected through additional line with cathode chamber inlet. A part of degassed and treated solution can be withdrawn from anode chamber by means of special arrangement installed on above-mentioned line. On a special line, container with catalyst is installed with inlet and outlet in its upper and lower parts, respectively. This container encloses a mixture of carbon and manganese dioxide particles. Degassed and treated solution withdrawal arrangement is made, for instance, as separator with tangential inlet, whereas treated solution supply and withdrawal means is made in the form of collectors. A means is also available to connect two or more cells. EFFECT: improved structure of apparatus. 5 cl, 2 dwg, 2 tbl

Description

 The invention relates to chemical technology, in particular to devices for electrochemical treatment of water with the aim of purifying and regulating acid-base, redox properties and catalytic activity, and can be used to obtain detergents and disinfectants.

 In applied electrochemistry, electrolyzers of various designs are used that provide water treatment or the production of washing and disinfecting solutions.

 A device for the separate production of water processed in the cathode and anode chambers of catholyte and anolyte from salted water, respectively used as a washable and disinfecting solution in medicine.

 The device includes a diaphragm flow-through electrolyzer with flat electrodes and a power supply unit combined with a control unit.

 A disadvantage of the known solution is the unsatisfactory hydrodynamics, the mixing of the products of the anodic and cathodic electrochemical reactions when using a large flow diaphragm, as well as the high cost of manual labor when assembling and repairing a cell with flat electrodes.

 A device for a water electrolyzer is known, which consists of a cylindrical electrolyzer with electrodes coaxially located in the electric bushings and a diaphragm between them, dividing the internal space into the cathode and anode chambers. Each chamber has a separate entrance to the lower and a separate exit in the upper bushings of the electrolyzer, communicating with the inlet and outlet hydraulic lines for the flow of water under pressure. The device includes a direct current source connected to the electrodes of the electrolyzer through a switching unit, which makes it possible to change the polarity of the electrodes to eliminate cathode deposits with the simultaneous switching of hydraulic lines, ensuring a constant flow of solutions from the anode and cathode chamber without mixing. It is noted that during the operation of this device, it is possible to obtain electrochemically treated water with bactericidal properties.

 The disadvantages of the known solutions are large energy losses during water treatment, especially when treating water with time-varying mineralization. The wider the range of possible changes in water mineralization, the higher should be the electric power of the used DC source.

 The closest in technical essence and the achieved result is a device for electrochemical water treatment.

 The device comprises at least one electrochemical cell made of vertical coaxial cylindrical and rod electrodes installed in dielectric bushings, an ultrafiltration diaphragm made of zirconium oxide ceramic, coaxially mounted in the bushings between the electrodes. The geometric dimensions of the cell satisfy certain relationships.

 The cells are specially fixed in the lower and upper collectors of dielectric material with supply channels, and the cells installed in the collectors are connected in parallel hydraulically and in parallel or in series-parallel electrically.

 The electrodes of the cell are connected to the poles of the current source so that the cylindrical electrode is the anode and the rod electrode is the cathode. The device contains a source of water to be treated, with which the electrode chambers are connected in parallel, flow regulators installed on the water supply lines to the electrode chambers on the water drainage line from the anode chamber. The device also contains a water-jet pump for dispensing a reagent coming from a tank installed on the water supply line, a tank with a catalyst and hydraulic piping, a current source connected through a switching unit with electrodes. The solution treated in the anode chamber is a disinfectant; the solution processed in the cathode chamber is used as a detergent.

 However, the process of water treatment in this device is associated with a relatively large energy consumption, in addition, requires a significant number of reagents for washing cells.

 The aim of the invention is to reduce energy consumption, expanding the functionality of the device by increasing the intervals for changing the properties of anolyte and catholyte, in particular by increasing the biocidal properties of solutions while reducing their corrosivity.

 The goal is achieved in that a device for producing washing and disinfecting solutions by electrolysis of an aqueous solution of sodium chloride, containing at least one electrochemical cell made of vertical coaxial cylindrical and rod electrodes installed in dielectric bushings, a coaxial ceramic ultrafiltration diaphragm installed in the bushings between electrodes and dividing the interelectrode space into the electrode chambers, and in the lower and upper bushings are made respectively channels for supplying and discharging the treated solution to the electrode chambers, devices for supplying and discharging the treated solution, respectively connected to the lower and upper bushings, a water supply line with a device for dispensing sodium chloride into water connected to it, connected through a flow regulator with a device for supply of the solution to the electrode chambers, the current source, the positive and negative poles of which are connected to the electrodes, and the supply line of the treated solution is connected to the chambers the negative electrode, and the output of the chamber of the negative electrode is connected by an additional line to the entrance to the chamber of the positive electrode and a device is installed on this line to enable the removal of part of the degassed treated solution from the chamber of the negative electrode, a container with a catalyst with an entrance at the top and the outlet is installed on the additional line in the lower part, which contains a mixture of carbon particles and manganese dioxide, a device for removing a degassed treated solution and it holds, for example, a separator with a tangential inlet, furthermore, devices for supplying and removing the treated solution formed as collectors and are provided with means for parallel connection of two or more cells.

 In applied electrochemistry, sequential passage of the cathode and anode chambers by the treated solution is known. However, in the known solution, the sequence of water flow through the electrode chambers is determined on the basis of the requirements for its purification from heavy metal ions, and the main process in the chambers is the process of changing pH, and in significant sizes. In particular, in the cathode chamber until a pH is achieved that exceeds the pH of hydrate formation, followed by separation of the precipitate on the filter and acidification in the anode chamber.

 In the proposed solution, it is essential that the solution processed in the cathode chamber together with the released hydrogen is sent to the anode chamber. At the same time, pH regulation does not play the main role, since the pH changes insignificantly, and the process is based on redox reactions on the electrodes and in the solution volume, which allow washing and disinfecting solutions with desired properties to be obtained.

 In FIG. 1 and 2 are variants of technological schemes of electrochemical synthesis of washing and disinfecting solutions: in FIG. 1 is an embodiment of an additional line connecting the negative electrode chamber to the input of the positive electrode chamber; in FIG. 2 option of turning on the catalyst on a special connection line.

 A device for producing washing and disinfecting solutions (Fig. 1 and 2) contains an electrochemical cell 1, which can be used as an electrochemical cell described in the prototype (application PCT WO 93/20014), the vertical coaxial electrodes (anode and cathode) of which are connected with poles of a current source (not shown). A ceramic diaphragm, also installed coaxially between the electrodes, divides the interelectrode space into the anode and cathode electrode chambers. The cathode chamber is connected by a supply line 2 of the solution to be treated, including a water supply line 3 and a salt solution supply line 4. The output of the negative electrode chamber (cathode chamber) is connected by an additional line 5 to the input of the positive electrode chamber. On line 5, a device 6 is installed, the Katolit valve, to enable the removal of part of the degassed treated solution from the negative electrode chamber, made, for example, in the form of a separator with a tangential inlet. On an additional line 5, a container with a catalyst containing a mixture of carbon particles and manganese dioxide can be installed (Fig. 2), which allows, by controlling the content of “active” catholyte compounds, to directionally change the properties of the anolyte, removing its corrosion activity.

 The device operates as follows.

 The initial processed solution containing water and sodium chloride in the required proportions enters the negative electrode chamber (cathode) of the electrochemical cell 1. The amount of sodium chloride in water is determined by the conditions of the problem being solved. The current source is turned on. Further, the state of the Katolit 6 (K) valve affects the ongoing process.

 When the Katolit valve (K) is closed, the entire volume, together with the hydrogen released during the electrolysis, enters the anode chamber.

В результате биоцидная активность анолита увеличивается, коррозионная активность снижается (pH 7,2-7,6).Reaction

As a result, the biocidal activity of the anolyte increases, the corrosion activity decreases (pH 7.2-7.6).

Включение емкости с катализатором позволяет за счет нейтрализации части "активных" соединений католита увеличить полезную нагрузку в анодной камере, так как часть тока, расходуемая ранее на нейтрализацию активных соединений католита, включается в "полезную" работу по изменению свойств анолита, что позволяет без существенного изменения pH увеличить его биоцидную активность.If the valve "K" is opened and part of the degassed catholyte is discharged, the specific amount of electricity to receive anolyte increases

The inclusion of a container with a catalyst allows, due to the neutralization of a part of the “active” catholyte compounds, to increase the payload in the anode chamber, since the part of the current consumed earlier to neutralize the active catholyte compounds is included in the “useful” work to change the properties of the anolyte, which allows without significant changes pH increase its biocidal activity.

 The invention is illustrated by the following example.

 Example. For water treatment, the cell described in PCT patent WO 93/20014 with titanium electrodes with platinum or platinum-iridium coatings and a ceramic ultrafiltration diaphragm was used. The treatment was subjected to a solution containing 2 g / l of sodium chloride at a power consumption of 1.8 kW / l.

With valve 6 closed (Katolit valve) and supplying the entire solution from the cathode chamber, together with the hydrogen released, the bactericidal activity of the anolyte was 16 min, and its corrosion activity was 10 mm / g. (Biocidal activity was evaluated by the time (min) of disinfection of 1 liter of water containing bacteria of the E coli group at a concentration of 1 • 10 ⁷ kg / l with the addition of 1 ml of anolyte with 300 mg / l of active chlorine in water.

 Corrosion activity was determined by the corrosion rate of metal samples (Art. 3) by the gravimetric method and was converted into a standard indicator mm per year).

The anolyte had a pH of 8.5 and an ORP of +780 mV relative to the silver chloride reference electrode. When diverting part of a degassed catholyte, i.e. with the valve "6" open and a 10% catholyte tap, the anolyte had the following characteristics:
Biocidal activity, min 13
Corrosion activity, mm / year 1.9
pH 6.5
ORP, mV +860 relative to silver chloride reference electrode
In this case, a quantity of catholyte with a pH of 8.0, an ORP of 650 mV, which can be used as a washing solution, was developed.

 When an anolyte with the following characteristics was used on an additional line of a container with a carbon dioxide manganese catalyst, anolyte was obtained (Table 1).

 According to the prototype, the characteristics of the resulting solutions are given in table. 2.

 As shown by the data presented, the proposed solution allowed us to obtain a bactericidal solution (anolyte), the functionality of which is wider than in the prototype, due to more precise regulation of changes in its parameters, increasing biocidal activity while reducing corrosion activity.

Claims (5)

 1. A device for producing washing and disinfecting solutions by electrolysis of an aqueous solution of sodium chloride, containing at least one electrochemical cell made of vertical coaxial cylindrical and rod electrodes installed in dielectric bushings, a coaxial ceramic ultrafiltration diaphragm installed in the bushings between the electrodes and separating the interelectrode space on the electrode chambers, and in the lower and upper bushings respectively made channels for supply a and the discharge of the treated solution into the electrode chambers, devices for supplying and discharging the processed solution, connected respectively to the channels of the lower and upper bushings, a water supply line with a device for dispensing sodium chloride into water mounted on it, connected to a device for supplying the processed solution to the electrode camera, a current source, the positive and negative poles of which are connected to the electrodes, characterized in that the supply line of the solution to be treated is connected to the camera from itsatelnogo electrode, a negative electrode output connected to an additional line chamber to the exit chamber of the positive electrode and the additional line is set to allow the adaptation of diverting a portion of the degassed solution processed from the negative electrode chamber.  2. The device according to p. 1, characterized in that on the additional line there is a tank with a catalyst with an entrance at the top and an exit at the bottom.  3. The device according to claims 1 and 2, characterized in that the container with the catalyst contains a mixture of carbon particles and manganese dioxide.  4. The device according to claims 1 to 3, characterized in that the device for draining the degassed solution is made, for example, in the form of a separator with a tangential input.  5. The device according to claims 1 to 4, characterized in that the device for supplying and discharging the treated solution is made in the form of collectors and equipped with means for parallel connection of two or more cells.

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