RU2310018C2 - Device for synthesis of oxidants from sodium chloride aqueous solution - Google Patents

Abstract

FIELD: flow-through plants for forming mixture of oxidants from sodium chloride aqueous solutions.

SUBSTANCE: proposed device has first line including the water flow regulator, salt solution reservoir, salt solution metering unit, electrolyzer producing the sodium hypochlorite solution from sodium chloride solution and pipe line for transportation of hypochlorite. Device is also provided with additional line with water flow regulator at its inlet. This line is connected with hydrochloric acid reservoir through metering pump. Outlets of these lines are connected via mixer forming common outlet for product.

EFFECT: increased yield of active chlorine.

1 dwg

Description

The invention relates to electrochemical unipolar processing of liquid media, which makes it possible to give these media widely adjustable stable and metastable properties of disinfecting solutions, which can be used in various fields of human activity, while reducing the environmental burden on nature.

Specifically, the proposed technical solution relates to the design of flow-through plants for generating a mixture of oxidants at the point of consumption from aqueous solutions of sodium chloride.

A known installation for the synthesis of oxidants in diaphragm electrolyzers from a solution of sodium chloride according to patent RU 2088539, according to application No. 95109074, which implements a method for producing oxidants that is close to that proposed for the final product.

The known device contains essentially an electrolytic cell, a water supply line to the electrolyzer with a device for dispensing sodium chloride into the water installed on the supply line. The sodium chloride solution is passed sequentially through the cathode and anode chambers.

In this case, the regulation of product properties is achieved due to the partial discharge of the resulting catholyte.

A disadvantage of the known method for producing a mixture of oxidants is the large amount of NaCl salt remaining in the resulting product, and the high energy costs due to the process being conducted in a diaphragm electrolyzer.

Installation according to patent RU 2088539 adopted as a prototype.

The aim of the invention is to eliminate these disadvantages, as well as increasing the yield of active chlorine.

This goal is achieved by the fact that the device is made in the form of two lines with water flow regulators at the beginning of these lines, the first of which has a flow-through diaphragmless electrolyzer connected through a metering pump to a container with a solution of sodium chloride, and connected to the second line through a pump the dispenser is a container with hydrochloric acid, while the outputs of these lines are connected through a mixer to a common outlet pipe of the finished product.

The drawing shows a diagram of the proposed device for producing a mixture of oxidants at the place of consumption from a solution of sodium chloride.

The device contains: a pipeline - 1, a water flow regulator - 2, a hydrochloric acid dispenser - 3, a container with a hydrochloric acid solution - 4, a water supply line - 5 through a regulator - 6 to a flow electrolyzer - 7 that produces sodium hypochlorite; a container with a concentrated solution of sodium chloride - 8, connected through a dispenser - 9 with an entrance to the electrolyzer - 7, a mixer - 10 and an outlet pipe of the finished product - 11.

The operation of the device.

Tap water is supplied through a pipeline 1 through a flow regulator 2 to a mixer 10. From a container 4, a dispenser 3 supplies hydrochloric acid to the water stream of the pipeline 1.

Through line 5, water is supplied to the flow electrolyzer 7. From the tank 8, an aqueous solution of sodium chloride is fed through the dispenser 9 to the inlet of the electrolyzer 7, where the salt concentration decreases to 15-20 g / l. In a flowing electrolyzer 7, a solution of sodium hypochlorite is produced with a concentration of up to 7 g of active chlorine per liter. In the mixer 10, the hypochlorite content in the solution with acidified water is reduced to a concentration of 100-1000 mg / L.

The finished product is a mixture of oxidants obtained by the interaction of hydrochloric acid and sodium hypochlorite, enters the consumer through the pipe 11.

Modification of hypochlorite with hydrochloric acid allows you to vary the ratio of concentrations of hypochlorous acid and hypochlorite in the mixture over a wide range.

For example, at a solution pH of 8-8.5, the mixture contains almost only hypochlorite with a slight admixture of hypochlorous acid.

With a decrease in pH to 7-7.5, the ratio between hypochlorite and hypochlorous acid is almost equal to one.

At pH 2.5-3, hypochlorite decomposes almost completely with the release of chlorine, followed by the formation of hypochlorous acid.

Industrial applicability.

The production of such devices is feasible on existing universal equipment.

Claims (1)

A device for the synthesis of oxidants from an aqueous solution of sodium chloride, including a first line in which there is a water flow regulator, a salt solution tank, a salt solution dispenser, an electrolyzer that produces a sodium hypochlorite solution from a sodium chloride solution, and a pipe for transporting hypochlorite, characterized in that the device is equipped with an additional line with an inlet water flow regulator, to which a container with hydrochloric acid is connected via a metering pump, and the outputs of these lines are connected through a mixer in overall product yield.