JPS61502450A - Method and apparatus for automatically controlling electrochemical purification process of wastewater - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Field of the invention: Method and device for automatically controlling the electrochemical purification process of wastewater The present invention relates to a method and apparatus for maintaining the process of wastewater purification, and more particularly to a method and apparatus for maintaining the process of wastewater purification. Also relates to a method for automatically controlling the process of electrochemical purification and an apparatus for carrying out the method. It is.

prior art Currently, wastewater treatment systems are in place to ensure that the amount of pollutants in wastewater is reduced to acceptable sanitary standards. The most efficient method and apparatus for automatically controlling the electrochemical purification process of water is It is related to changing the density of the current.

West German Patent No. 2,016,448 (IPC: BOIK 3100.1974) wastewater by adjusting the current density on the electrodes, as exemplified in A method for automatically controlling an electrochemical purification process and an apparatus for carrying out the method are known. There is. The device has an electrode mass connected to a power source and a device for adjusting the current density on the electrode. Equipped with monitoring equipment. The adjustment device is a device that presets the required current density on the electrodes. , and the signals emitted by the mass monitoring device and the current density precent device. It is equipped with a signal comparator circuit to compare the actual value of the current density, thus changing the actual value of the current density to the power supply. Generates control signals to be sent.

However, these known methods for automatically controlling the electrochemical purification process of wastewater and The device is only effective if the proportion of pollutants in the wastewater supplied for purification remains unchanged. Brings about efficient purification. This is because by maintaining a constant current density on the electrodes, This produces a certain amount of metal hydroxide sufficient to clump the contaminants. It's for a reason. The current density on the electrode increases as the proportion of pollutants in the wastewater increases. This known device is not sufficient.

Purification efficiency is therefore affected while the concentration of pollutants in the wastewater being treated changes.

This is because the amount of metal hydroxide produced in this case is proportional to the concentration of the pollutant. This is for a good reason.

by varying the current density on the electrodes in response to changing concentrations of pollutants in the wastewater. Therefore, a method for automatically controlling the electroflotation process for purifying wastewater and a device for performing the coughing method are proposed. location is known. (Reference: Soviet Union Inventor's Certificate No. 453,360 IPC: C 02F 3100. Published in 1972).

The signal emitted by the monitoring device based on the residual concentration of suspended solids in the purified water is A control that is compared with a reference signal in the device and given to the input of the power supply in case of an error. Generate a signal.

The methods and devices described above will only improve the efficiency of the purification process if the dynamics of the process are taken into account. ensure proper control. Otherwise controllable variation is highly unstable This may make the purification process unstable.

Additionally, in response to the concentration of dissolved metals in the water being purified, Automatic control of wastewater electrochemical purification process characterized by adjusting the current density of (Reference: USSR Inventor's Certificate No. 555,056 IPC: C02F 3100). In this method, the molten metal of the electrode in the water being purified is It is based on maintaining the optimum concentration sufficient for the degree of purification. That is in waste water. The flocculation of pollutants suspended in water occurs at a sufficiently high rate for a given amount of dissolved metal in water This is because it is known to occur. Excessive presence of dissolved metals in water The concentration of dissolved metals in the wastewater being treated affects the degree of purification and the degree to which the water is purified. It follows a pattern of being influenced by the edge of the head. However, there are various It is said that monitoring the melt metal concentration is difficult due to the presence of impurities. Due to the fact that it is impossible to precisely maintain the desired concentration of dissolved metals in water .

The equipment for this method consists of a controllable power supply connected to the consumable electrode of the electroconcentrator, and and a current density adjustment device. The current density regulator adjusts the current density on the consumable electrode. A device for presetting the required value and a comparator circuit with its output connected to a controllable power supply It is equipped with

The device also connects to the comparison circuit of the current density regulator to conveys information about the actual value of the current density on the electrode corresponding to the concentration of molten metal in the Equipped with a device that measures the concentration of dissolved metal at the electrode in the water being treated, which generates a signal that There is. It carries information about the actual and desired current density on the electrodes and is used in the comparator circuit. The mismatch between the signals applied to the inputs can be addressed by varying the current density on the electrodes. I respond. As a current density adjustment device, it responds to the concentration of dissolved metal in the water being treated. Electrochemistry of wastewater in an electrocoagulator through stepwise changes in current density on the electrodes Using an optimization stage controller that allows maintaining optimal process conditions for Ru.

However, known monitoring devices that determine the concentration of molten metals in the water being purified has a measurement error of more than 5%, which affects the quality of purified water.

Summary of the invention The purpose of the present invention is to accelerate the agglomeration of impurities and increase the degree of water purification. The melting of electrodes in water during processing can be monitored by continuously monitoring the mass of consumable electrodes. An electrochemical purification process of wastewater that allows to precisely retain the optimum amount of metals. The object of the present invention is to provide a method and device for automatic control.

The object of the invention is to provide a current density on the consumable electrode of an electrocoagulator in which electrochemical purification is carried out. In a method for automatically controlling the electrochemical purification process of wastewater by varying the Therefore, according to the present invention, the mass of the electrode changes with time while dissolution of the electrode progresses. by adjusting the current density on the consumable electrode in response to the

Preferably the current density on the consumable electrode is kept within the range of 0.005 to 0.02 A/- do.

It is also an object of the present invention to provide a controllable power supply connected to the consumable electrode of the electroconcentrator, and an output a device for connecting the power to a controllable power supply and presetting the desired value of the current density on the consumable electrode; Signal comparison, which compares the signals corresponding to the desired and actual values of the current density on the consumable electrode Automatic electrochemical purification process of wastewater, equipped with circuit and current density regulating device According to the invention, in an apparatus for carrying out a method of controlling, the mass of a consumable electrode is monitored. A device is provided for adjusting the current density on the consumable electrode. and connected to the consumable electrode through a flexible suspension and an insulating plate. , the actual current density on the consumable electrode corresponding to its mass at any given moment. This is accomplished by generating a signal that conveys information about the value.

Preferably, the device includes a container made of dielectric material and filled with a conductive liquid; The free end of the conductor connected to the power supply inside the device is immersed in liquid, and the conductor connected to the insulating plate is exposed to the liquid. The far end is also immersed in a container containing conductive liquid.

Preferably, mercury is used as the conductive liquid.

The proposed invention allows the consumable electrode to be adjusted in response to or based on a change in its mass. The highest required current density is ensured, which results in a high degree of water purification as well as anode metal This makes it possible to minimize losses. On average, the associated benefits are depleted The metal consumption of the electrode is reduced to 77%, and the degree of wastewater purification is increased to 3.2%. ~4.8% increase.

Brief description of the drawing Hereinafter, the present invention will carry out the proposed method for automatically controlling the electrochemical purification process of wastewater. More details may be found with reference to various specific embodiments in connection with the accompanying drawings, which are schematic illustrations of the apparatus. Explain.

Preferred modes for carrying out the invention The essence of the proposed method to automatically control the electrochemical purification process of wastewater is the electrification of wastewater. The current density on the consumable electrode of the electrocoagulation device where the chemical treatment is carried out is The current density is preferably adjusted in response to changes in the mass of the electrode over time. It is to be maintained within the range of O, OO5 to 0.02 A/cffl.

In electrochemical purification of wastewater, the degree of water purification and the efficiency of the electrocoagulation device is greatly influenced by the amount of metal in the consumable electrode that is applied to land water with a voltage applied to the electrode. Receive the sound. The ions of the consumable electrode that are imparted to the water during treatment under the action of an electric current are hydroxyl High yield that interacts with oxide ions to promote agglomeration of impurities contained in water. It produces metal hydroxide particles that are capable of adhesion. Then the condensed impurities The aggregates are separated from the purified water in a flocculator.

The amount of metal sent into the water must be proportional to the amount of impurities contained in the water. . The above-mentioned facts are useful for carrying out electrochemical purification of wastewater, in which case the required water Ensures cleanliness and process efficiency. This is consumption’! Maintains a given current density on the electrode. This is achieved by promoting high rate dissolution of the electrode. Theoretically positive The amount m of extremely molten metal is determined by Faraday's law, that is, m = K - J ・t Can be set by However, K is the electrochemical equivalent of the metal of the consumable electrode 1. J is the amount of current on the consumable electrode and t is the time required to melt the metal on the consumable electrode.

However, in reality, the amount of metal that can be dissolved in an electrocoagulator under the action of electricity is different from the theoretical yield. In this context, consumable electrodes are required to achieve the desired degree of purification. It is important to accurately determine the amount of metals added to the wastewater during the electrochemical dissolution of It is. Prior art methods of determining the amount of molten metal in water in monitoring instrument means include The problem is that the degree of measurement is quite low (the measurement error of known meters is as high as 4-5%). . The most accurate are devices that measure the change in the mass of a meltable electrode under the action of an electric current It is. The proposed device therefore reduces the amount of metal delivered from the consumable electrode into the water being treated. It utilizes technology that continuously determines the water purification process over time as the water purification process progresses. Ru.

The greatest benefit is when the consumable electrode melts at a current density on the electrode of o, oos ~ 0.02 A/-. This is achieved when understanding. At current density below 0.005A/a11, the electrode melts. This results in a reduction in speed, which affects the efficiency of the electrocoagulator. On the other hand, 0 ．． A current density above 0.2 A/ci indicates a more active liberation of gas from the electrode, which This results in excessive mixing of wastewater during treatment, which deteriorates the purification process.

A method for automatically controlling the electrochemical purification process of wastewater is provided by the apparatus schematically shown in the attached drawings. It is done by The device comprises a controllable power source 1, which is used to turn off the electroconcentrator 3. a device 5 connected to the consumable electrode 2 and for briscenting the required current density on the consumable electrode 2; and the required density value of the current and the actual density value generated by the mass measuring device 7. Current density adjustment of any known suitable structure, comprising a comparator circuit 6 for comparing the corresponding signals. Connect to device 4. (Reference: 13. Russia edited by pJ, Kosharsky Glossary “Pr1bory i upravlyajuschie system” ydlja khimicheskikh proizvodstv'' (Ma shinostroenie” Publisher, Moscow, 1976)).

The device 7 is connected to the consumable electrode 2 via a flexible suspension 8 and an insulating plate 9. There is. The controllable power source 1 is made of dielectric material to prevent electrical contact with the power source 1 and is free from mercury. Conductive wires 10 and 11 with their free ends immersed in a container 12 filled with a conductive liquid such as It is connected to the consumable electrode 2 through the consumable electrode 2.

The consumable electrode 2 is located at the lower part of the electrocoagulation chamber 13 of the electrocoagulation device 3, and the metal of the electrode 2 is melted. The electrolyte is placed almost above the inlet pipe 14 that supplies pure electrolyte to the electrocoagulation chamber. A tube 15 for supplying is arranged above the electrode 2.

The electrocoagulation chamber 13 is arranged coaxially inside the settling chamber 16 and occupies a part of this chamber 16. ing. The settling chamber 16 has outlet pipes 17 and 18 for discharging purified water and waste, respectively. is provided.

The degree of purification of wastewater and the passing capacity of the electrocoagulator 3 are mainly determined by the electrochemical effect of the consumable electrode 2. Determined by the amount of metal hydroxide produced in the electrolyte while dissolution proceeds . The efficiency of the purification process therefore characterizes the amount of metal hydroxide delivered into the electrolyte. It depends on the availability of continuous information regarding the mass of the consumable electrode 2. Empty and consumable electrode A mass monitoring device 7 that continuously provides data regarding the mass of wastewater This is the main element of the device that automatically controls the purification process.

The mass monitoring device 7 is a "nozzle-gate" device based on the distance between the nozzle and the gate. A "nozzle-gate" pneumatic device ( Reference: V, M, Kulakov"Pr1bory old ja khimich eskjkh proizvodstv” (Russian, “Khimiya "Publisher, Moscow, 1983, p. 500))" The flexible suspension 8 can be connected to the flexible suspension 8 by a link device. consumable electrode 2 As the mass changes, the tension in the linkage also changes, causing movement of the gate relative to the nozzle. and a change in the pressure in the device corresponding to the change in the mass of the electrode 2. Electrode 2 is water Conductor wires 10 whose free ends are immersed in a container 12 filled with a conductive liquid such as silver; 11, it is connected to the power supply 1.

Carrying out the proposed method for automatically controlling the electrochemical purification process of wastewater according to the present invention The device operates as follows.

The waste water is collected in a consumable tube made of aluminum, for example, and positioned at the bottom of the electrocoagulation chamber 13. It is continuously supplied to the middle part of the electrocoagulation chamber 13 through a pipe 15 disposed above the electrode 2. be provided. At the same time, an electrolytic solution such as industrially pure water is introduced into the electrocoagulation chamber through the inlet pipe 14. 13, and this electrolyte flows upward through the interelectrode gap between the consumable electrodes 2. flows. The voltage applied to electrode 2 causes the electrode to dissolve in the electrolyte, thus resulting in a high sorption ability to produce metal hydroxide particles, which are electrocoagulated by an upward flow of electrolyte As a result of the electrolysis of highly dispersed gas water sent to the middle part of chamber 13, electrode 2 It is accompanied by the emanation of et al.

Above electrode 2, the waste water is mixed with an electrolyte containing the products of the melting of the metal of electrode 2. As a result, interactions between metal hydroxides and contaminant particles occur, leading to large agglomerations of the particles. These bodies are carried towards the surface of the liquid by air bubbles and thus become suspended. The waste material contained in the sedimentation chamber 16 is continuously discharged from the upper part of the settling chamber 16 via an outlet pipe. sedimentation The purified water in the chamber 16 is discharged via an outlet pipe 17 provided in the lower part of the cough chamber.

Continuous monitoring of the change in mass of the consumable electrode 2 while water purification progresses is carried out using a flexible suspension mass monitoring device 7 connected to electrode 2 via section 8 and insulating plate 9. become. The melting of the electrodes 2 is accompanied by a change in their mass, and the “node” of the mass monitoring device 7 is This results in a displacement of the suspension 8 connected to the "Zur-Gate" device.

At the output of this fruiting device 7, the mass of the consumable electrode 2 and therefore the current on the consumable electrode 2 Conveys data regarding the amount of total hydroxide produced in the electrolyte based on density A signal is generated. This signal is then input to the comparator circuit 6 of the current density regulator 4. and the other input of the regulating device corresponds to a predetermined value of the current density on the consumable electrode 2. A signal from device 5 is provided. The error between these signals allows current density adjustment. The device 4 controls the operating mechanism of the power source 1 according to certain regulation laws. As a result A proportional change in the current density applied to the electrode 2 occurs and the output of the comparator circuit 6 of the regulating device 4 The rate of anodic melting of the metal of consumable electrode 2 is increased based on the sign of the error signal generated by Or a reduction occurs.

Therefore, when the mass of the electrode 2 changes, the control signal of the current density regulator 4 changes It operates to change the calculation parameters and reset the required current density on electrode 2, and This ensures the stabilization of the predetermined operating conditions for the purification of wastewater in the electrocoagulation chamber 13. This promotes high-quality purification.

The efficiency of controlling the electrochemical purification process of wastewater is based on the conditions under which the electrodes operate. Therefore, the linear velocity of the electrolyte flow in the electrode gap and the distance between the electrodes are electrochemical melting of the gas and electrode 2 while minimizing passivation of their surfaces. Choose to make the conductivity continuous so that it is saturated with the products of the solution.

The proposed method for automatically controlling the electrochemical purification process of wastewater and the equipment for carrying out the method The device purifies wastewater by approximately 99.6% and reduces electrode wear to 77%.

two! applicability The present invention is useful for purifying wastewater contaminated with organic matter, non-sediment matter, solid matter, etc. Can be applied.

The present invention applies to petroleum products such as wastewater containing oil and polymethyl methacrylate. It can be most beneficially used to purify wastewater contaminated with Wear.

international v4 distortion report

Claims (5)

[Claims] (1) Consumable electrode (2) of an electrocoagulation device (3) that performs the electrochemical purification process of wastewater Automatically control the electrochemical purification process of wastewater by changing the density of the current on the In the method, the density of the current applied to the consumable electrode (2) is adjusted to The adjustment is made based on the fact that the mass of the electrode (2) changes with time during the progress of the process. The method described above. (2) The density of the current on the consumable electrode (2) is within the range of 0.005 to 0.02 A/cm. Electrification of wastewater according to claim 1, characterized in that it is kept within a A method for automatically controlling the chemical purification process. (3) A controllable power source (1) connected to the consumable electrode (2) of the electrocoagulation device (3) ), the output is connected to the controllable power source (1), and the output is connected to the consumable electrode (2). device (5) for presetting the required value of the current density of the current on said consumable electrode (2); a signal comparison circuit (6) for comparing signals corresponding to the desired and actual values of the density; The wastewater according to claim 1, comprising: a current density adjustment device (4) comprising: In a device that performs a method for automatically controlling the electrochemical purification process of connected to the current density adjustment device (4) above and the flexible suspension (8) and At any given moment, connected to the consumable electrode (2) through an insulating plate (9) Information regarding the actual value of the current density on said electrode corresponding to the mass of said consumable electrode (2) The above, characterized in that it is provided with a mass monitoring device (7) that generates a signal conveying information. Device. (4) A container (12) made of a dielectric material and containing a conductive liquid is provided, and the container (12) is made of a dielectric material and contains a conductive liquid. In step 12), the free end of the lead wire (10) of the controllable power source is immersed in liquid; 0) is connected to the controllable power source (1) and further connected to the insulating plate (9). 1) Wastewater according to claim 3, characterized in that the free end is immersed in liquid. A device that performs a method for automatically controlling the electrochemical purification process of (5) Claim 4, characterized in that mercury is used as the conductive liquid. equipment.