RU200898U1 - ANODIC OXIDATION UNIT - Google Patents

Abstract

The invention relates to wastewater treatment systems, devices for preliminary oxidation and preparation of water for coagulation treatment. Anodic oxidation unit for wastewater treatment from organic and inorganic substances, which is a housing 1 with plane-parallel electrodes, cathodes 3 and anodes 2, equipped with a means for feeding oxygen into the interelectrode space with an aeration panel. The branch pipe for supplying purified water is located in the lower part of the body and is equipped with a branch pipe for introducing reagents 5, in the lower part of the anodic oxidation unit there is a splitter of water flow 6, directly under the electrodes there is an aeration panel 7 equipped with an air supply device made of porous polyethylene or polypropylene pipes for air supply, while the purified water outlet is equipped with a reagent inlet 5, and the overflow pocket is equipped with a pH correction device.

Description

The invention relates to wastewater treatment systems, devices for preliminary oxidation and preparation of water for coagulation treatment.

There is a known installation for water purification according to the patent PM 6562, which includes an electrocoagulator with a set of soluble metal electrodes, a pressure flotation device with a system of pipelines for supplying an air-water mixture and an electroflotator with a set of insoluble electrodes.The device is additionally equipped with a pre-anodic oxidation unit located in front of the physical and chemical treatment unit.

Known patent No. 2176989 (Bakhir V.N., Zadorozhny Yu.G., Leonov B.I., Panicheva S.A.) Installation "AQUACHLOR" consists of flow-through modules, each of which is a diaphragm cell with coaxially installed electrodes and a diaphragm ...

Cathodes and anodes are made of titanium tube, while the anode is coated with ruthenium and iridium oxide. The ceramic diaphragm is made of zirconium oxides, yttrium aluminum.

The closest in technical essence is RF Patent 2566404 dated 02.27.2015 CO 2 F 9/12 "Water treatment plant", which includes an electrochemical processing unit. The unit contains an electrochemical oxidation unit with cathode-anode electrodes in the form of plates coated with ruthenium oxide, and a multichannel membrane compressed air aerator located under it.

The electrochemical oxidation unit with cathode-anode plate electrodes includes electrodes, while one of the electrodes is made of iron, and a multi-channel membrane compressed air aerator is located under the above-mentioned electrochemical oxidation unit,

The installation is equipped with at least one submersible filter element and the bottom of the section was connected to a sludge receiver.

The disadvantages of the device include the following.

The plant generates sodium hypochlorite, which in turn acts as an oxidizing agent. If the amount of chlorides in the water is insufficient, it must be added. Hypochlorite is a cleaner, but not a strong one, for example, it cannot clean non-ionic surfactants, ethylene glycol and a number of other organic substances. The installation is expensive, since yttrium, ruthenium, and iridium are used in its production. The presence of a membrane complicates installation and impairs conductivity.

The technical problem is to create an anodic oxidation unit for efficient oxidation of organic and inorganic substances dissolved in water. The technical result consists in increasing the efficiency of water purification of various origins and degrees of pollution by creating a reactor for the direct synthesis of atomic oxygen by an electrochemical mechanism.

An anodic oxidation unit for purifying wastewater from organic and inorganic substances, which is a housing with plane-parallel electrodes, cathodes and anodes, equipped with a means for supplying oxygen to the interelectrode space, A branch pipe for supplying purified water is located in the lower part of the housing and is equipped with a reagent inlet pipe in the lower part of the anodic oxidation unit there is a water flow divider, directly under the electrodes there is an aeration panel equipped with an air supply device, made of porous polyethylene or polypropylene pipes for air supply, while the purified water outlet is equipped with a reagent inlet pipe, and the overflow pocket is equipped with a pH device. correction.

The anodic oxidation unit is characterized by the presence of a plastic case (1) in which plane-parallel plates are installed: anodes (2) - graphite (titanium, coated titanium), cathodes (3) - steel (carbon or stainless). Water supply is carried out from bottom to top through a splitter (6) - a flow equalizer made in the form of a conical body inside which there are blades.

The divider ensures uniform water supply to the anodes.

A device for supplying air or a water-air mixture is installed under the electrodes - an aeration panel, which is designed to saturate the supplied water with air oxygen. This ensures the rapid removal of hydrogen from the cathodes (there is no need for membranes), while the electrical conductivity of the liquid does not decrease, depassivates the anodes (this preserves conductivity), creates a film liquid-phase / heterophase oxidation mode with an additional amount of oxygen dissolved in water, which increases the oxidizing power and equipment efficiency ...

The current densities supplied to the electrodes of 100–250 A / m ² are chosen so that the oxygen released during electrolysis dissolves in water and oxidizes the substances dissolved in the water, and hydrogen "flows" vertically upward along the cathode surfaces. Water is poured through the walls of the electrochemical bath into a trough located around the perimeter of this bath. The collecting chute is equipped with a "pelvis" for accommodating a pH meter (10), a red-ox meter or other ionometer for automatic control of the BAO. The outlet (9) from the anodic oxidation unit (BAO) is equipped with a reagent feed. At the inlet and outlet of the anodic oxidation unit, there are nozzles (5) for introducing a coagulant, which enters into a chemical reaction and chemisorbs the oxidized products obtained during the anodic oxidation of dissolved substances. It is possible to introduce both the same reagent and different ones to condition the water at the outlet from the BAO. An aeration panel (7) is located under the electrodes, designed to saturate the supplied water with air oxygen through the air supply device (8). The panel is made of porous polyethylene or polypropylene pipes, which are supplied with air. Air mixes the water in the anode space and adds dissolved oxygen, which increases the oxidation efficiency in the BAO. To create the necessary medium (pH, mass transfer medium, coagulant, etc.), the inlet pipe is equipped with a reagent inlet pipe (5). To correct the composition of oxidized water, the BAO overflow pocket is equipped with a pH correction device (10).

FIG. shows a schematic representation of the anodic oxidation unit, where

1 - housing with electrodes in the form of plane-parallel plates

2 - anodes

3 - cathodes

4 - inlet pipe for water supply

5 - reagent inlet pipe

6 - flow divider

7 - aeration panel

8 - air supply device

9 - outlet branch pipe

10 - pH correction device.

The Anodic Oxidation Unit is designed for:

- direct oxidation of substances in the anode zone;

- generation of dissolved oxygen for the subsequent oxidation of organic and inorganic substances;

- generating oxidants (for example, hypochlorite) from salt solutions for their subsequent use for oxidizing dissolved substances or disinfecting water.

In the interelectrode space, the processes of oxidation of substances occur, while it is possible to dose catalysts into the interelectrode space to improve the course of the processes and avoid the reversibility of the reaction.

The device oxidizes organic substances and inorganic substances dissolved in water.

The technical result in comparison with the RF Patent 2566404 is achieved by regulating the composition of water in the interelectrode space using reagents introduced through the reagent injection pipe (5) and dosage of air oxygen through the aeration panel (7), which is equipped with an air supply device (8) and the absence of ceramic membrane, which has a negative effect (decrease in electrical conductivity) on the oxidation process and its power.

pH adjustment (10) at the outlet (9) and the dosage of the reagent create conditions for highly efficient use of the formed atomic oxygen.

For example: Composition of water before entering BAO

Iron 2+ 5 mg / l Methanol 3 mg / l Ammonium ion 5 mg / l Formic acid <0.1 mg / l Nitrate ion 0.5 mg / l COD 35 mgO ₂ / l BOD ₅ 20 mgO ₂ / l

After passing through the installation with a flow rate of 1 l / h and a current of 1.5 A, the composition of the water changes.

Iron 2+ <0.1 mg / l Iron 3+ 5 mg / l Methanol 0.5 mg / l Ammonium ion 0.6 mg / l Formic acid 3.5 mg / l Nitrate ion 7.5 mg / l COD 20 mgO ₂ / l BOD ₅ <4 mgO ₂ / l

Claims (1)

An anodic oxidation unit for purifying wastewater from organic and inorganic substances, which is a housing with plane-parallel electrodes, cathodes and anodes, equipped with a means for supplying oxygen to the interelectrode space, characterized in that the pipe for supplying purified water is located in the lower part of the housing and is equipped with an inlet pipe reagents, in the lower part of the body of the anodic oxidation unit there is a splitter of the water flow, directly under the electrodes there is an aeration panel equipped with an air supply device made of porous polyethylene or polypropylene pipes for air supply, while the outlet is equipped with a reagent inlet, and the overflow pocket is equipped a pH correction device.

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