RU93086U1 - ELECTROLYSIS INSTALLATION - Google Patents

Abstract

In the context of the ever-expanding introduction of advanced technical solutions in the field of water and wastewater treatment in the water sector, scientifically based water quality control is one of the most important factors in the sanitary and epidemiological well-being of settlements, as well as the prevention of technological and environmental disasters. In recent decades, a solution of sodium hypochlorite NaClO containing active chlorine, which is equivalent to pure chlorine in its disinfecting and sterilizing qualities, has been increasingly used all over the world. Its use practically removes all dangerous and harmful production factors inherent in the use of liquid and gaseous chlorine - a potent toxic substance. The advantages of using sodium hypochlorite include the possibility of obtaining it directly at the place of consumption by electrolysis of cheap and affordable raw materials - sodium chloride (sodium chloride). Moreover, the sodium hypochlorite solution obtained by the electrochemical method (grade E according to TU 6-01-29-93) is the purest and least toxic product (hazard class 4 according to GOST 12.1.007-76) and has the highest efficiency. Currently, the efficiency and productivity of electrolysis plants for the production of sodium hypochlorite has increased significantly. It was possible to overcome a number of technological problems associated with the production of electrolytic sodium hypochlorite. Designed and manufactured plants for the production of sodium hypochlorite have various capacities and various purposes. They can be used: - for disinfecting natural and wastewater in domestic and drinking water supply; - for the disinfection of equipment, facilities and structures in the food industry, in health facilities, catering, sanatoriums and rest homes, child care facilities, swimming pools and other facilities; - to prevent biofouling in water heating and cooling systems; - to provide temporary or permanent water supply in emergency situations or in remote garrisons of the Armed Forces of the Russian Federation. Technological schemes of electrolysis plants can be either flowing or periodic. When using flow-through electrolyzers, it becomes possible to reduce the cost of servicing plants, as it is much easier to control the process here. Depending on the type of raw materials used, electrolysis plants can be divided into plants for the electrolysis of an artificially prepared solution and for the electrolysis of natural brines. The advantages of electrolytic sodium hypochlorite as an effective bactericidal agent, the simplicity and reliability of electrolysis plants, as well as the interest of consumers in the use of a safe electrochemical method of water disinfection, have led to the creation of a huge number of plants with a variety of designs. The most widely used electrolysis plants operating according to the following flow chart. A saturated solution of sodium chloride is prepared in the tank, salt is loaded and filled with tap water. The supply of tap water to the tank is carried out through the float valve, with which a constant water level is maintained in the tank. Water passing through a layer of sodium chloride and dissolving it is saturated with sodium chloride. To obtain a saturated salt solution with a NaCl content of 30 g / l, the salt layer above the intake filter (dead volume) must be at least 15-20 cm. As the electrolysis system operates, the salt layer decreases and when it decreases to the dead volume level, it is necessary to replenish the tank . The saturated solution of sodium chloride is taken by a metering pump through a pipeline located at the bottom of the tank. The inlet of the pipeline is equipped with a filter. A saturated solution of sodium chloride enters the pipeline for the preparation of a working solution of sodium chloride, which also contains tap water for dilution to a predetermined concentration of a solution of sodium chloride. Control of the flow of tap water is carried out by the meter and is regulated by a valve or tap. The prepared working solution enters a flowing electrolyzer, consisting of several electrolytic cells in which electrolysis is carried out, as a result of which sodium hypochlorite of a given concentration of chlorine and hydrogen is formed. The cell is connected to a direct current source. The resulting sodium hypochlorite enters the hypochlorite reservoir, where hydrogen is separated from hypochlorite. From the reservoir, sodium hypochlorite is pumped by a metering pump for chlorination. Dosing of active chlorine is carried out by changing the pump speed. Hydrogen released during electrolysis is removed by forced ventilation outside the room into the atmosphere. The electrolysis installation is equipped with automation elements that control the work process and turn off the installation in case of violation of the technological mode of operation.

Description

The utility model relates to the field of engineering, in particular to the designs of electrolysis plants.

Known electrolysis installation for producing a solution of sodium hypochlorite from a solution of sodium chloride (patent for utility model No. 69523).

The basis of this utility model is the task of creating a universal automatic small-sized design of a portable electrolysis unit to obtain a disinfecting reagent of sodium hypochlorite in places of its use, as well as increasing the safety of operation.

The problem is solved in that the entire set of equipment of the electrolysis unit is mounted on a single frame, equipped with a rotameter, an electric control valve, a flow sensor (water meter), hypochlorite level sensors, a processor for processing incoming information and issuing control signals, it is located optimally, ready for use and provides the preparation and dosage of sodium hypochlorite.

Improving the safety of operation of the installation is achieved by eliminating the possibility of hydrogen entering the sewage pipelines of the room by electrolysis.

Thus, the automatic production process of sodium hypochlorite is ensured and the operation safety of the electrolysis plant is increased.

Technological schemes of electrolysis plants operating on sodium chloride solutions can be either flow-through or with a batch system. The main difference between the parameters of flow electrolysers and the parameters of batch electrolysers is that in the first case, the electrolysis process can be considered stationary, time-independent. Moreover, if the brine flow rate and the current load on the cell remain constant, then the concentration of the sodium hypochlorite solution removed from the cell remains unchanged.

In batch electrolysis plants, the concentration of sodium hypochlorite depends on the time elapsed since the start of electrolysis. In this case, the maintenance personnel should spend much more time on the organization of the process due to the fact that he is forced to fill the electrolyzer several times a day with a solution and drain sodium hypochlorite from them.

The implementation of the proposed utility model is considered on the example of the technological scheme of the electrolysis installation in figure 1. All water entering the electrolysis unit passes through an ion-exchange softener 1 and enters a container 2 for preparing a concentrated salt solution. In the tank of the salt solution there are drain 3 and overflow 4 pipes and pipelines. The unit for supplying a concentrated solution of sodium chloride consists of a filter 5 and a metering pump 6. A ball valve 7, a valve with an electric actuator 8, a flow sensor (water meter) 9, provide a given flow rate of water supplied, controlled by a rotameter 10. The electrolyzer is supplied with power from a rectifier 11. Exit the cell is connected by a pipe 12 with a capacity of 13 for storing the finished sodium hypochlorite. The hypochlorite tank is equipped with a nozzle 14 and an air duct 15. The fan 16 creates an air pressure for the forced removal of hydrogen into the atmosphere. The hypochlorite tank is equipped with a drain 17 and overflow 18 pipes and pipelines, and a Z-bend 19 is mounted on the overflow pipe of the hypochlorite tank, which acts as a water seal and prevents the mixture of gases from entering the sewage pipe. The storage tank for the obtained hypochlorite is additionally equipped with level sensors 20 for automating the process of preparing hypochlorite and a pipe for supplying sodium hypochlorite with a metering pump 21 to the entry points for water disinfection. The installation is equipped with a control and alarm panel 22, in which there is a control processor for processing incoming information and issuing control signals.

From the above description it is clear that the proposed utility model can be implemented not only in accordance with the considered example of its implementation, but also in other specific forms without deviating from the essence of the utility model defined by its formula.

Claims (5)

1. An electrolysis unit for the production of sodium hypochlorite, consisting of a container for dissolving sodium chloride, the inlet of which is connected to a water supply for dilution, equipped with an ion exchange softener, which removes hardness salts in water (calcium and magnesium salts), and the outlet pipe is connected to a metering pump for feeding the initial solution of sodium chloride into the electrolyzer, the outlet of which is connected to a reservoir for storing the obtained sodium hypochlorite, and the reservoir is equipped with a pressure fan with a nozzle for forced release of hydrogen into the atmosphere and a nozzle for supplying sodium hypochlorite for disinfection of water connected to a metering pump, characterized in that it also includes a rotameter for visual determination of the volumetric flow rate of water for electrolysis, a control valve with an electric actuator for changing the volume of supplied water a flow sensor (water meter) for recording water flow for electrolysis, as well as a processor for processing incoming information and issuing control signals. 2. The electrolysis installation according to claim 1, characterized in that the containers for preparing the initial salt solution and storing the obtained hypochlorite are additionally equipped with drain and overflow pipes and pipelines, and a Z-shaped bend is installed on the overflow pipe of the hypochlorite tank, which acts as a water seal and prevents ingress gas mixtures in the sewer pipeline. 3. The electrolysis plant according to claim 2, characterized in that the storage tank for the obtained hypochlorite is additionally equipped with level sensors to automate the process of preparing hypochlorite. 4. The electrolysis installation according to claim 3, characterized in that the control panel, water softener, metering pumps are located between the tank for the preparation of salt solution and the tank for hypochlorite, and the flowing electrolyzer is located in the lower part of the installation, in the immediate vicinity of the tank of salt solution and containers for hypochlorite. 5. The electrolysis installation according to claim 4, characterized in that the entire set of equipment is installed on a single portable frame and ensures the production and dosage of sodium hypochlorite.