RU2477707C2 - Method of water cleaning and decontamination - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: set of intention relates to water treatment and may be used in various industries. First, chlorinated coagulant is subjected to electrochemical treatment at membrane or diaphragm electrolysis unit 3 with insoluble electrodes to produce high-basic coagulant and gaseous chlorine. High-basic coagulant is mixed with water flow fed into settler 4 for coagulation and flocculation of undissolved suspensions and mechanical impurities. Gaseous chlorine withdrawn from electrolysis unit is fed into chlorine proportioner 6 to make bleaching water. Said water is fed for decontamination in cleaned water flow between said settler 4 and mechanical filter 8.

EFFECT: higher quality of purification.

2 cl, 1 dwg, 3 tbl

Description

The invention is intended for the purification and disinfection of drinking and waste water and can be widely used in various sectors of the economy where water treatment is necessary (chemical, metallurgical, oil refining, medical industry, public utilities, etc.). It can also be used to produce chlorine, chlorine water and chlorine-containing coagulants of various basicities.

The invention includes: an automated process control and management system (ACS TP) 1; reagent preparation system 2 for dissolving the starting reagents and dosing them; electrolysis unit 3 for producing chlorine and coagulant of various basicities with improved properties; sedimentation tank for coagulation and flocculation of insoluble suspensions and solids 4; floc removal device 5; a device for dosing chlorine and producing chlorine water 6; mechanical filter 8.

EFFECT: chlorine-free purification and disinfection of water with higher quality indicators of treated water and lower costs to achieve this goal, achieved by optimizing the parameters of the process and taking into account the individual characteristics of the source water.

The invention is intended for the purification and disinfection of drinking water and can be used to purify various effluents of arbitrary origin. The invention can also be used for the production of chlorine, the chlorination of various substances, the production of chlorine-containing coagulants of different basicities, in medicine for the production of highly effective disinfectant solutions, for the production of inorganic adhesive solutions, in metallurgy, in the oil refining industry, for bleaching various materials, etc.

Known and widespread methods used at pumping and filtering stations are technical solutions that purify and disinfect water using coagulants delivered to these stations (ready-made solutions or in solid form, followed by preparation of working solutions) and liquid chlorine in tanks, containers or cylinders (with subsequent dosing of chlorine in disinfected water from these tanks and chlorine storage), which is dangerous during transportation, operation and storage ( .A.Kulsky, P.P.Strokach. The technology of water purification. Kiev, Visha School, 1986, 352 pp., S.27-39).

The disadvantages of such stations are:

1) the need to purchase and store large quantities of hazardous chlorine;

2) the high costs of using expensive coagulants of high basicity or a large number of cheap coagulants of low basicity;

3) used coagulants for water purification have a weak coagulating and disinfecting effect;

4) the lack of the possibility of acquiring coagulants of optimal basicity, intended for the treatment of water of a particular water source, taking into account the individual composition of its water;

5) the lack of the possibility of obtaining chlorine from a coagulant while optimizing the degree of purification, chlorination of water and minimizing the cost of the reagent;

6) the lack of the possibility of automatic self-adjustment of reagents to their optimal properties at the station according to the indicators of purified water;

7) restrictions on the use of low-base coagulant (the cheapest of the whole series of chlorine-containing coagulants of different basicities) due to its high acidity.

A known installation for producing a chlorinating agent (RU 2090519 C1, 1997, CL C02F 1/76, C25B 1/26). The installation includes an electrolyzer, an electrolyte preparation and dosing unit, and a communications system. Moreover, an electrolyzer with separated anode and cathode chambers was used as an electrolyzer. The installation comprises a flow line for water and a collector-separator. The unit for preparing and dispensing the electrolyte solution includes a solution unit, an osmotic dispenser, and pipelines forming a circulating electrolyte circuit. The installation also contains a unit for cleaning the electrolyte solution from hardness salts.

A known water disinfection station, producing both sodium chloride solution and caustic soda from a solution of sodium chloride (RU 2281252 C2, 05/10/2006). The station includes an electrolyzer, a unit for dissolving and dosing sodium chloride, an ejector, and communications. Between the electrolyzer and the ejector is installed a circulation circuit containing an alkali storage device, a heat exchanger and a pump. The dissolution and metering unit consists of an adjustment tank, a salt tank, a metering pump, a rotameter and an accumulating tank. To separate chlorine and alkali, the electrolyzer is equipped with an ion-exchange membrane. This solution provides "... an increase in the bactericidal activity of the resulting disinfectants, ensuring the explosion safety of the process."

The main disadvantage of the above technical solutions is that they provide only safe disinfection of water with chlorine, sodium hypochlorite and chlorine water and do not provide cleaning from insoluble impurities and suspensions.

Closest to the proposed method in terms of technical nature and the achieved result is the technical solution set forth in the RF patent No. 2163894 dated March 10, 2001, “Method for the purification and disinfection of water” (RU 2163894 C2, March 10, 2001, bull. No. 7). This method provides a technical solution that allows the use of a gas-liquid suspension of coagulant and chlorine for the simultaneous purification and disinfection of water by electrolysis of a solution prepared on the basis of a chlorine-containing coagulant.

The main disadvantages of this method are:

1) the formation of an explosive mixture of chlorine and hydrogen above the surface of the resulting coagulant solution;

2) the inability to accurately control the basicity of the resulting coagulant containing disinfecting components based on dissolved active chlorine;

3) due to the lack of separation of the anode and cathode zones, higher energy costs are observed compared to the proposed method, which is associated with a mixture of the reaction products of the cathode and anode spaces and the production of a certain amount of gaseous oxygen;

4) the difficulty of obtaining pure chlorine with non-guaranteed and unstable composition parameters from an explosive mixture of chlorine and hydrogen, which does not allow accurately dosing chlorine into the treated water.

The objective of the invention is the creation of a safe and highly effective method of purification and disinfection of water and the creation of a treatment station that provides for the purification and disinfection of contaminated water using chlorine-containing coagulants due to: simultaneous production of chlorine water; coagulant of optimal basicity, with high bactericidal properties. The coagulant basicity and amount of the disinfecting component is selected and optimized by the automated process control system (ACS TP) of water treatment by assessing the main indicators in the treated water (content of insoluble impurities and the content of disinfecting components, etc.) by controlling the amount of their supply by metering pumps in the preparation system reagents 2, the selection of the coagulant from the electrolysis unit 3 and the control of the electrical load on the cell. The optimization of the technological process is carried out according to two main criteria: high regulated quality of water treatment and low technical and economic costs.

The problem is solved by the proposed method and the water purification and disinfection station, which includes: an automated process control system (ACS TP) 1; a reagent preparation system 2, feeding them to an electrolysis unit 3 to produce chlorine and a highly basic coagulant having high coagulating and disinfecting properties, containing active chlorine; devices for dosing chlorine and producing chlorine water 6; sedimentation tank for coagulation and flocculation of undissolved suspensions and solids 4; a device for removing flakes 5 after flotation; mechanical filter 8 (see figure 1).

For purification and disinfection of water, low-basicity chlorine-containing coagulant and reagents that prevent the passivation of electrodes of electrolysis unit 3 are used, which are fed to the reagent preparation and supply system 2, where their optimum ratio is controlled and selected by an automated process control system (ACS) 1. Then, prepared the solution enters the electrolysis unit 3, in which a coagulant is obtained containing active chlorine and separately chlorine gas, from which to the device TBE the chlorine and chlorine water preparation 6 chlorine water is obtained. A coagulant containing active chlorine is selected from the electrolysis unit in two streams and mixed in the optimal proportion, then mixed with a stream of purified water, which, in turn, is purified in settler 4 by coagulation and flocculation of undissolved suspensions and mechanical impurities. At the same time, preliminary chlorination is carried out in settler 4, from where heavy sediments are removed by a sediment removal device 7, and light suspensions are removed by a flake removal device 5. To disinfect water, chlorine or chlorine water is fed into the purified water flow between the settler for coagulation and flocculation of undissolved suspensions and mechanical impurities 4 and a mechanical filter 8. The remaining amount of coagulated mechanical impurities is cleaned by a mechanical filter 8. Automated process control system eskim process (ACS) 1 monitors and controls all the above process steps.

The cathode and anode spaces of the electrolysis unit 3 are separated (in contrast to the above analogues and prototypes) with a special diaphragm or membrane that passes the resulting solution inside the electrolysis unit 3, but prevents the passage of hydrogen and chlorine bubbles through it, which eliminates the formation of explosive gas mixtures. The electrolysis unit 3 extracts chlorine from the coagulant solution in the anode space of the electrolyzer and directs it for the final chlorination of the purified water with chlorine or in the form of an aqueous solution with chlorine water. Automated process control system (APCS) 1 allows you to control all process indicators: the concentration of the initial and main substances formed, the filling levels of technological equipment with solutions, the voltage and current values on the electrodes, the electrolysis mode, the costs of the main flows of the dosed and formed substances, the main parameters of the purified and disinfected water (transparency and concentration of residual active chlorine or the resulting coagulant with active chlorine), the levels of settler precipitation. It allows you to control the process using actuators, adjusting to the optimal basicity of the coagulant obtained in the electrolysis process of a more basic (compared to the original, having higher coagulating and disinfecting indicators) coagulant and the required amount of chlorine by changing the voltage and current on the electrodes of the electrolysis unit 3 and managing the flow of substances at all stages of water treatment in automatic, manual or mixed modes, combining automatically cue and manual at the same time. As a result, the work of the station is optimized according to the established criteria for the quality of water treatment and the criteria for minimizing the costs of achieving these goals, taking into account the individual composition and properties of the treated water and the safety of the process.

The main difference between the method and the station from analogues and prototypes is that a chlorine-containing coagulant of any basicity can be used at the water treatment and disinfection station, namely Me (OH) _m Cl _nm , where Me is the metal, n is the valency of the metal, am is the number hydroxyl groups in the metal hydroxychloride, where Me is the metal, n is the metal valency, am is the number of hydroxyl groups in the metal hydroxychloride, and is in the range 0 <m <n.

At the same time, a more effective coagulant of higher basicity and separately chlorine or chlorine water are obtained. Moreover, this process is easily regulated by a simple change in the electrical load on the electrodes of the electrolysis unit 3 and is optimized using ACS TP 1.

Among coagulants, low-base coagulants are the easiest and cheapest to obtain, but their coagulating properties are significantly lower compared to highly basic coagulants.

We give an example on coagulants from aluminum hydroxychloride (GOHA). In the series of coagulants 1/3-GOA (Al (OH) Cl ₂ ), 2/3-GOA (Al (OH) ₂ Cl) and 5/6-GOA (Al ₂ (OH) ₅ Cl), the first is obtained from aluminum hydrate and hydrochloric acid, the second is obtained at higher temperatures and pressures using solutions containing alkaline and alkaline earth elements or using metallic aluminum. The latter highly basic coagulant is obtained, as a rule, from metallic aluminum or with the addition of metallic aluminum. The cost of the latter, depending on the quality, increases several times. The technical solution presented makes it possible to use even aqueous solutions of hydroxychloride in hydrochloric acid as a coagulant, which can be obtained in the cheapest way — by leaching clays containing alumina with hydrochloric acid. Moreover, the lower the basicity (more chlorine in the compound), the much easier chlorine is extracted. The cost of electrolysis of chlorine in an acidic environment is always lower, which is associated with a decrease in voltage for the implementation of this process. Moreover, from the cheapest and less effective coagulant, after extraction of chlorine, a more effective coagulant of higher basicity is obtained. Moreover, purchases and storage of chlorine are completely excluded, purchases of other substances for the production of chlorine and chlorine water are reduced, and the cost of directly producing the coagulant itself (GOA or aluminum chloride solution) is also significantly reduced, and there is no chlorine hazard due to the absence of chlorine storage.

Another fundamental difference is that the method and device make it easy to adjust the properties of the resulting coagulant by changing its basicity in the right direction, taking into account the characteristics of the water being purified. This can never be done by the industrial production of coagulants due to the impossibility of releasing a wide range of coagulants of different basicities for each water source separately (the nomenclature will reach hundreds, if not thousands of coagulants of different basicities).

There is a long-known fact that in various places existing water sources have their own highly individual properties and compositions (alkaline, neutral and acidic with different compositions of salts dissolved in them, with different contents of insoluble mechanical impurities and suspensions, etc.).

That is why an individual approach is necessary when selecting reagents for water treatment, i.e. For water purification, not only a highly basic coagulant should be used, but a special coagulant with special basicity that is specific to a particular water.

This is confirmed by the work of numerous pumping and filtering stations and water utilities, where they are forced to select and use their various types and doses of coagulant and chlorine, and these doses vary depending on the time of year.

In fact, for these purposes, at stations, due to the lack of better, only the coagulant that chemical industry enterprises can release is used.

The proposed solution makes it easy enough to optimize the properties of the coagulant by controlling the load and controlling the flow rate of the initial low-base coagulant to obtain a coagulant of almost any basicity and specific (optimal) basicity necessary, in particular, for a particular water source.

This is achieved by the aggregate regulation of the composition of the solution in the preparation of reagents 2; controlling the flow rate of the coagulant to the input of the electrolysis unit 3; the operation mode of the electrolysis unit 3; selection of a coagulant containing active chlorine from the electrolysis unit 3 (in the optimal proportion from the anode and cathode zones).

The third fundamental difference is that, along with the production of chlorine or chlorine water separately, the solution of the resulting coagulant acquires another fundamentally new property: during electrolysis, together with improved coagulating ability, dissolved compounds of the hypochlorite, chlorate group with active oxygen and directly dissolved active are formed in it chlorine possessing higher bactericidal activity due to the use of additional oxidizing ability of active oxygen atoms Yes.

This effect allows preliminary chlorination (disinfection) in conjunction with the coagulation of impurities and suspensions without any supply of chlorine or chlorine water for these purposes.

Almost all types of chlorine electrolyzers have at least an inlet (opening) for supplying liquid raw materials, there are inlets for feeding water (in the case of ion-selective membranes) and no more than one outlet for selecting the final liquid product (for example, sodium hydroxide, sodium hypochlorite or aluminum oxychloride or suspension of aluminum oxychloride with chlorine, as in the specified prototype), there are also holes for the withdrawal of gaseous products (hydrogen and chlorine). Moreover, in all cases, they seek to obtain maximum concentrations of the final liquid products (sodium hydroxide, sodium hypochlorite, sodium oxychloride, aluminum hydroxychloride (high basicity with a maximum concentration in terms of Al ₂ O ₃ ).

In the present case, the electrolyzer has two openings for selecting the coagulant from different zones of the electrolysis space — the cathode and the anode. The final product of the operation of the electrolyzer is the product of mixing these coagulant streams, and the mixing proportions of these flows are determined by ACS TP according to the results of the purified water indicators at the outlet of the water treatment and disinfection station.

The effectiveness of cleaning and disinfection depends not only on the amount of reagent supplied (dosed into the cell) and exiting from it in two streams, but also on obtaining the optimum coagulant basicity after mixing with each other and the content of active disinfecting compounds that provide effective preliminary disinfection.

The limits and extreme values of mixing represent two extreme cases: this is when the entire coagulant flow passes either through the anode hole or through the cathode hole. Moreover, all intermediate mixing options between them are equally equally probable and depend on the quality of the treated water.

The second product of the electrolyzer is not just chlorine, but the optimal dosing (consumption) of chlorine (or chlorine water) with the help of an automated process control system at the final stage - at the stage of water disinfection by choosing the optimal mode (energy-efficient) of electrolysis of the solution.

And in general, the final product of the whole process is purified and disinfected water with minimal expenditure of expendable substances and energy for these purposes, and not a combination of substances obtained with high quality indicators (as all industrial electrolyzers usually work).

The design of the cell has its own characteristics. In the electrolyzer there is more than one hole with a nozzle for the selection of products, as is typical for all electrolyzers, in which they try not to mix anode and cathode solutions, but, on the contrary, isolate them from each other, which allows to achieve high quality products with minimal energy costs. These valves are connected to two valves controlled by ACS TP, which are then connected together through pipelines into a single stream. As a result, these flows are mixed. The holes in the cell (one in the anode space of the cell and the other in the cathode space of the cell) can be located anywhere, but it is preferable that they are as far as possible from the point of entry of the initial coagulant solution and on different sides of the separation membrane (diaphragm). The control of these two adjustable valves is carried out with the help of an automated process control system according to controlled indicators of the quality of water purification and disinfection (turbidity, chlorine concentration, pH, etc.). The cleaning efficiency depends not only on the amount of reagent supplied (dosed into the cell) and exiting from it in two streams, but on the preparation of the coagulant basicity (its quality) and the content of active disinfecting compounds providing effective preliminary disinfection.

The basicity and content of chlorine in the coagulant supplied to water purification depend not only on the load on the electrolyzer, but also on the degree of opening and closing of the adjustable valves. So, in the anode zone of the electrolyzer, the concentration of dissolved chlorine is much higher than in the cathode space, and in the cathode space the basicity of the dissolved coagulant is higher than in the anode. Using these features and adjusting the ratio of these flows, it is possible to select the optimal parameters of the coagulant for cleaning and disinfection, taking into account the characteristics of the water. The limits and extreme values of such adjustment are two extreme cases: when the entire coagulant flow passes either through the anode hole or through the cathode hole. In the first case, the coagulant solution contains the maximum amount of dissolved chlorine, in the second case - the minimum amount of dissolved chlorine. Moreover, all intermediate mixing options between them are also equally probable and the choice depends on the quality of the water being treated. When choosing the best option, it is better to do this with the use of industrial control systems, for a person it can be very burdensome.

The second product of the electrolyzer is not just chlorine, but the optimal dosing (consumption) of chlorine (or chlorine water) with the help of automated process control systems for the final stage - for the stage of water disinfection by choosing the optimal electrolysis mode.

And in general, the final product of the whole process is purified and disinfected water with the minimum expenditure of expendable substances and energy for these purposes, and not the totality of the substances obtained with high quantitative indicators for the content of the main active substance.

The coagulant leaving the electrolyzer contains various disinfectants, including active chlorine. To assess the concentration of chlorine in the coagulant obtained in the electrolysis unit 3 after mixing the anode and cathode flows, a chlorine sensor is monitored, which is installed in the pipeline at a distance of at least 20 pipeline diameters (generally accepted recommendations ensuring uniform mixing) from the place of mixing of the flows. Next, the coagulant is mixed with a stream of contaminated water in the sump for coagulation and flocculation of insoluble suspensions and mechanical impurities 4, in which the water is purified and pre-disinfected and bleached. In this case, the concentration of chlorine in the process of water purification drops sharply. Due to the fact that water has a different composition, and moreover, this composition is strongly influenced by the season (the most polluted water is in the spring-autumn periods of the year), it is not possible to predict the degree of absorption of chlorine and its residual content in the treated water. To this end, it is advisable to monitor the residual chlorine content with a chlorine sensor, which is installed in the pipeline after settling tank 4, but not reaching the point of entry of chlorine or chlorine water supplied for the final chlorination of purified water. The chlorine content in the purified water is monitored by another sensor, the location of this chlorine sensor is located in the pipeline at the outlet of the mechanical filter 8. In principle, for the station to work, it is sufficient to have only the last two chlorine sensors (after settling tank 4 and after mechanical filter 8). It is the analysis of the readings of these two sensors that allows you to correctly control the operation mode of the electrolyzer (including cathode and anode consumption of coagulants).

As an example, tests performed using a coagulant having the following characteristics can serve as: density of the initial solution ρ = 1.29 g / cm ³ ; Al / Cl ratio = 0.68; stoichiometric formula of aluminum hydroxychloride (GOHA) - Al (OH) _1.54 Cl _1.46 or Al ₂ (OH) _3.08 Cl _2.92 ), Al ₂ O ₃ content 16.3%, Cl 16.62 %

Table 1 Change in basicity with chlorine extraction by electrolysis The original form of GOHA Al ₂ (OH) _3.07 Cl _2.93 Concentration in solution The weight Al ₂ O ₃ Cl H ₂ O GOHA g 16.63 16.62 66.08 33.92 % 16.63 16.62 66.08 33.92 Al ₂ (OH) _4.38 Cl _1.62 The weight Al ₂ O ₃ Cl H ₂ O GOHA g 16.30 9.19 62.31 29.72 % 17.71 9.98 67.71 32.29 Al ₂ (OH) _4.76 Cl _1.24 The weight Al ₂ O ₃ Cl H ₂ O GOHA g 16.30 9.08 61.72 30.16 % 17.74 9.88 67.17 32.83

The production of chlorine for water treatment was carried out on an electrolyzer with an anode of titanium coated with ORTA and with the separation of the anode and cathode zones by a special membrane.

Electrolysis was carried out at different flow rates of the GOA solution. The feed of the initial coagulant was carried out both in the anode and in the cathode space. The concentration of active chlorine in the coagulant taken from the anode space reached 3125 mg / L. The concentration of active chlorine in the electrolyte taken from the cathode space was in the range from 57 to 170 mg / L.

The minimum value of active chlorine in the cathode space was observed when the initial GOA was introduced into the cathode space and when the highly basic GOA formed was drained after electrolysis from the anode space. One GOA sample — anolyte — has a density of 1.28 g / cm ³ .

Product formula: Al ₂ (OH) _4.76 Cl _1.24 , active chlorine content up to 3125 g in the coagulant solution leaving the anode zone 3125 mg / l. Additionally, pure chlorine was obtained, from which chlorine water was obtained.

The composition of chlorine water was obtained similar to the composition of chlorine water, as when dosing pure chlorine from cylinders to water.

Another composition of GOHA after electrolysis: the density of the solution was 1.19 g / cm ³ , which corresponds to the formula GOHA - Al (OH) _2.19 Cl _0.81 (Al ₂ (OH) _4.38 Cl _1.62 ). The content of Al ₂ O ₃ in the solution was 19.19%, Cl - 9.15% (according to calculations from the material balance, the GOXA formula has the following form Al (OH) _2.32 Cl _0.68 or Al ₂ (OH) _{4 , 64} Cl _1.36 ).

From various samples of GOHA produced in this way, 1% solutions were prepared in terms of Al ₂ O ₃ solutions and laboratory studies of test coagulation in the volume of river water on a flocculator were carried out in comparison with the coagulant aluminum sulfate (CA), traditionally used on pumping and filtering stations. The tests were carried out on river water in the most adverse temperature conditions.

Speed - 20 rpm.

Mixing time is 20 minutes.

Settling time - 30 min.

Water temperature - 1-3 ° C.

Product Quality Analysis:

1. Sample No. 1: Formula of the product Al ₂ (OH) ₅ Cl

2. Sample No. 2: Formula of the product Al ₂ (OH) _3,07 Cl _2,93

3. Sample No. 3: Product formula Al ₂ (OH) _3,75 Cl _2,25

table 2 Test coagulation using polyacrylamide Type of coagulant Units rev. Ref. GOHA to el. Number 2 GOHA after email. Number 3 CA CA Dose Mg / dm ³ - 13 13 13 fourteen PAA dose Mg / dm ³ - 0.1 0.1 0.1 0.1 Turbidity ret. Mg / dm ³ 2.82 1.17 1,08 3.92 2.85 pH offset water 7.17 6.9 6.94 6.77 6.69 Oxidation of Protected Water Mg / dm ³ 17.4 9.28 9.92 10,4 10,4 The remainder. distilled water aluminum Mg / dm ³ - 0.37 0.33 1.17 0.97 Color chr. water Hail fifty eighteen eighteen thirty 25

Table 3 Test coagulation using polyacrylamide Type of coagulant Dose Turbidity water pH Oxidation of water Residual Water Aluminum Water color Mg / dm ³ Mg / dm ³ Mg / dm ³ Mg / dm ³ Mg / dm ³ Hail Source water - 5.16 7.12 20.1 - fifty CA fourteen 1,5 7 - 1.72 thirty GOHA No. 1 from the dispenser Al ₂ (OH) ₅ Cl 13 1.17 7.17 10.86 0.17 19 GOX No. 1 Al ₂ (OH) ₅ Cl 2 1,5 7.02 - 0.6 twenty GOHA №2 after electronic. Al ₂ (OH) _3.75 Cl _2.25 13 1,03 7.23 11.48 0.37 19 GOHA No. 3 after electrolysis, anolyte Al ₂ (OH) _4.38 Cl _1.62 13 0.8 7.17 9.62 0.35 eighteen

Findings:

1. Water treatment with hydroxychlorides of different basicities in the winter is quite effective.

2. All samples of hydroxychlorides work in the current period much more efficiently than aluminum sulfate.

3. Residual aluminum is much better removed by highly basic hydroxychloride, and overall, highly basic GOA is more effective for a given river water.

4. Chlorine water obtained by electrolysis has the same properties as chlorine from containers dissolved in water.

Claims (2)

1. The method of purification and disinfection of water, including preliminary electrochemical treatment of a solution of chlorine-containing coagulant in an electrolysis unit with insoluble electrodes, obtaining a highly basic coagulant and gaseous chlorine, characterized in that the highly basic coagulant is obtained in a membrane or diaphragm electrolysis unit and mixed with a stream of water to be purified served in the sump for coagulation and flocculation of undissolved suspensions and solids; chlorine gas extracted from the anode space of the electrolysis unit is sent to a chlorine dosing and chlorine water production device, the chlorine water obtained is disinfected into a stream of purified water between the settling tank for coagulation and flocculation of undissolved suspensions and solids and a mechanical filter. 2. Water purification and disinfection station, including a reagent preparation system, an electrolysis unit with insoluble electrodes, a settling tank for coagulation and flocculation of insoluble suspensions and mechanical impurities, a device for removing sediment, a mechanical filter, characterized in that it additionally includes an automated process control and monitoring system process (ACS TP), a device for dosing chlorine and producing chlorine water, equipped with a chlorine capture system and a buffer tank for storing chlorine water, pumps, sensors, flow meters and valves for controlling the flow of chlorine and chlorine water, while the electrolysis unit has a diaphragm or membrane that separates the cathode and anode space.