CN1107443A - Effluent treatment involving iono-oxidation treatment - Google Patents

Abstract

The method for purifying waste water features that waste water flows up through plastic column, in which complex electrode of anode made of Fe and Al and cathode made of Fe is immersed in water, and a plastic tank with bottom in shape of funnel is arranged at the top of plastic column. When current flows through electrode, the impurities in waste water is separated out by electrochemical reaction. Then water is filtered, or micro air bubbles are sprayed upward for carrying suspended solid to float, discharging out of column top.

Description

The present invention relates to a wastewater treatment method for purifying wastewater and circulating the treated water, especially for effectively removing dissolved/undissolved impurities in wastewater generated by various industries such as textile/chemical processes waste water from production.

The wastewater generated in the above mentioned industrial units, especially the textile/chemical wastewater contains the following impurities which need to be effectively removed by proper treatment:

Total Suspended Solids (T.S.S), Total Dissolved Solids (T.D.S), Biochemical Oxygen Demand (B.O.D), Chemical Oxygen Demand (C.O.D), Oils and Greases, Pigments, Detergents, Ammonia, Sodium Percentage, Heavy Metals and Toxic Compounds , including phenols, also need to bring the pH to an acceptable level.

These impurities are usually removed by coagulation-flocculation-sedimentation process, followed by appropriate secondary and tertiary treatment after controlling the pH value. Combinations of these treatments do not always remove the aforementioned impurities to acceptable tolerances, in addition to pH, and moreover, they produce excess sludge containing extremely high concentrations of impurities and are prohibitively expensive.

Furthermore, for high flows of textile wastewater, these methods or systems require a large space due to the long residence period. These methods or systems are sensitive to the nature of the atomic groups in the water.

In the traditional coagulation-flocculation-sedimentation process, aluminum sulfate, ferric chloride and ferrous sulfate are used. The chemical way to remove impurities is as follows:

Flocs of hydroxides of aluminum, ferric iron and ferrous iron are insoluble in a certain pH range during precipitation, and they can remove impurities in wastewater, aluminum ions, ferric ions and ferric iron The ions can also react chemically with pigmented impurities and eventually with the precipitation of reaction products. This approach is expensive in terms of recurring costs.

People try to solve this problem by adopting traditional dissolved air flotation equipment (DAF system). In the known DAF system, the coagulated wastewater is pumped together with compressed air into an air dissolving pipeline through a pressure pump, usually at a pressure of 55 to 85 psig, and then the pressure in the effluent is quickly released, causing the excess air to become fine particles. Submicroscopic bubbles. Such conventional DAF equipment requires a high capital investment because it requires specialized equipment such as high-pressure pumps, piping, containers, and the like. In the same technical field, the following patents are also found, but do not teach any new technical features of the present invention:

France: 2488870A

Russia: 1161477A

Russia: 966025A

Japan: 79164761 (791220)

Germany: 3830344A

United States: 4540052

European patent: 82810484 (821111)

European patent: 82107779 (820825)

The present applicant has invented an electrolytic method for treating textile waste water which is less expensive to implement than the same conventional treatment described above. The above-mentioned electrolysis method includes storing waste water (electrolyte) in a tank, transmitting direct current through a sacrificial steel electrode set in the tank, and generating highly active Fe ⁺² and Fe ⁺³ ions in situ within a predetermined time, As flocculants/ions, they react with hydroxide ions (OH) and eventually suspended/colloidal/dissolved impurities to form flocs, trap these impurities and remove color.

In the above electrolysis process, a direct current flows through the electrodes, according to Faraday's law

(Faraday's Law) Fe ⁺² , Fe ⁺³ and OH ^- are produced, which are consumed as a sacrificial electrode for the cathode. Fe ⁺² , Fe ⁺³ react with OH ^- ions and other fine suspended/colloidal/dissolved impurities to form flocs. These flocs trap suspended and/or colloidal impurities by absorption and/or adsorption during the process of settling to the bottom or floating to the top, thereby removing most of the appearance color. The chemical reaction formula in this process is as follows:

It is an object of the present invention to provide an improved method of wastewater treatment which purifies such wastewater by means of the electrochemical reaction of electrolysis in order to effectively remove all dissolved/undissolved impurities from such wastewater and to render such wastewater Wastewater can basically be recycled.

The applicant has also found in experiments that after the wastewater is treated by the improved electrolysis process to be described hereinafter, when the purified water is filtered, optionally, if necessary, microscopic water can be sprayed into the wastewater during the electrolysis process. With air bubbles, it is possible to achieve a more effective effect than has been achieved hitherto with conventional techniques.

Therefore the present invention provides a kind of waste water treatment, the method for purification, and this method comprises making the waste water to be treated flow up through a column made of plastics, there is the composite electrode immersed in it in this column, the anode of above-mentioned electrode is made of iron and aluminum, while the cathode is composed of iron alone, the column has at its top a reservoir made of plastic with a funnel-shaped bottom, in the case of energizing the above-mentioned electrodes, the upwardly flowing waste water undergoes an electrochemical reaction, The impurities in the waste water are thus separated and drained from the top of the column, the water is then filtered, passing the purified water through a filter medium, optionally, if so desired, in the electrolysis of the waste water During the process, submicroscopic air bubbles are injected upward through the column to carry the suspended and floating solids in the wastewater to be treated upwards for discharge through an outlet located at the top of the column.

The applicants have found that effective results can and can be achieved by a synergistic process comprising essentially electrochemical reactions, improved electrolysis, oxidation and flotation of dissolved air.

Accordingly, the present invention provides a method of treating waste water for purification and recycling, the method comprising flowing waste water upwards through a column made of plastic with composite electrodes submerged in water, said electrodes The anode is composed of a mixture of iron and aluminum, and the cathode is composed of iron alone. A plastic storage tank with a funnel-shaped bottom is arranged on the top of the above-mentioned column, and gaseous oxygen is introduced from the bottom of the column under a predetermined pressure. Oxygen bubbles flow upwards through the wastewater, causing the wastewater to undergo an electrochemical reaction while energizing the electrodes, whereby the wastewater undergoes a synergy of electrochemical, oxidation and dissolved air flotation treatments, due to this synergistic treatment the impurities are removed from the wastewater Separated, precipitated in a funnel-shaped storage tank at the top of the tower, and then drained from the top of the column, and the purified water was discharged from the top of the storage tank.

The applicant has previously studied a method for removing impurities in waste water to an allowable concentration range, such as phenols, COD, pigments and toxic substances (such as cyanides), and these waste waters are dyes and dye intermediates. Produced during manufacturing and textile industry processes, the method involves passing a predetermined amount of ozone in the form of fine bubbles through the bottom of a column containing highly polluted waste water and granular activated carbon in order to make the activated carbon The powder is fluidized and forms a fluidized bed, which increases the area of the interface between the activated carbon and the wastewater for ozone, thereby oxidizing the impurities in the wastewater into low-molecular polar biodegradable compounds. Can be adsorbed on the surface of the above-mentioned activated carbon, the biodegradable compound is kept in contact with the wastewater in the fluidized bed for a predetermined time, forming a layer of biofilm to retain the oxidation products that cannot be adsorbed on the above-mentioned activated carbon .

It was also found that there is a significant synergistic synthesis when ozone (O ₃ ) is passed through a column including highly polluted wastewater (such as from dye and dye intermediate production plants and textile chemical production plants, etc.) and granular activated carbon (GAC) In effect, when a sparger is used to direct the ozone into the bottom of the funnel, it flows upwards, keeping the bed of activated carbon particles fluidized. The chemical process involved in the present invention will be explained in conjunction with the following different approaches, which include:

i)

a) When ozone passes through the column, a large number of tiny bubbles increase the interface area between the ozone bubbles and the wastewater containing impurities, thereby improving the adsorption of ozone in wastewater. This increase in adsorption increases the oxidation of soluble impurities.

b) The fluidized bed of activated carbon provided by gaseous bubbles increases the interface area of ozone _O3 between activated carbon and wastewater. This effect increases the adsorption of impurities on the activated carbon surface.

c) Air bubbles also lead to the chemisorption of impurities on the activated carbon.

d) Through ozonation or activated carbon, intractable compounds that are difficult to remove or degrade can also be disposed of under this synergistic effect.

ii) Direct reaction of solutes (i.e., impurities dissolved in wastewater) with ozone; this type of reaction can be represented by a general formula:

M + O ₃ M'oxid + M"oxid

where M is the solute, and M'oxid and M"oxid are quasi-final oxidation products that are only very slowly or not further oxidized by ozone.

iii) Solute and scavenger substances such as: HCO ₃ humic acid, Cl ^- , NH ₄ , etc., oxidized by the OH functional group produced by the automatic decomposition of ozone.

Applicants have now found in experiments that a combination of electrolysis (as proposed herein) and ozone can be used to treat the same waste water to considerable effect.

The present invention further provides a waste water treatment method for treating waste water and purifying the waste water, the method comprising making the waste water flow upward through a column made of plastic, the post having a composite electrode submerged in water, the anode of the above electrode Composed of a mixture of iron and aluminum, the cathode of the above-mentioned electrode is composed of iron alone, and at the top of the above-mentioned column there is a sump with a funnel-shaped bottom, which is made of plastic. The method also includes passing ozone from the lower portion of the column at a predetermined pressure, causing ozone bubbles to flow upward through the waste water, causing it to undergo an electrochemical reaction while energizing the electrodes, thereby causing the waste water to undergo electrochemical, The synergistic effect of oxidation and dissolved air flotation treatment, because this combined treatment separates the impurities from the wastewater, and when the impurities settle into the funnel-shaped storage tank set at the top and bottom of the column, they are discharged from the top of the column, The purified water is drained from the top of the storage tank.

The applicant has further found in experiments that while adopting the improved electrolysis process described herein, when the wastewater to be treated is also fluidized, the synergistic effect of this treatment improves the performance of the system, such as purification efficiency , some difficult-to-handle compounds such as phenol, dyes, dye intermediates removal rate from wastewater, very low concentration and therefore difficult to remove the performance of the compound, the surface of the electrode can always be kept updated by scraping without Any attachment to improve the performance of the electrolysis itself can also increase the turbulence of the wastewater flowing through the column in order to improve the dispersion and mass transfer, making the system more compact.

Therefore, the present invention also provides a wastewater treatment method for treating wastewater so as to be purified, the method comprising flowing upwards the wastewater through a column made of plastic, the column having a composite electrode submerged in water, the electrode The anode is composed of a mixture of iron and aluminum, and the cathode is composed of iron alone. The top of the above-mentioned column has a tank made of plastic with a funnel-shaped bottom, so that when the above-mentioned electrode is energized, the upwardly flowing wastewater undergoes an electrochemical process. Reaction, in the wastewater to be treated in the above-mentioned column there is also activated carbon in the form of particles, the wastewater undergoes electrochemical treatment and fluidized bed treatment formed by activated carbon particles when the electrodes are energized, the impurities in the wastewater are separated and deposited into the bottom funnel of the storage tank and drain through the outlet.

In another embodiment, the present invention provides a wastewater treatment method for purifying wastewater comprising flowing wastewater upwardly through a column made of plastic having composite electrodes submerged in water, the above-mentioned The anode of the electrode is composed of a mixture of iron and aluminum, and the cathode is composed of iron alone. The top of the above-mentioned column has a tank made of plastic with a funnel-shaped bottom, so that the wastewater flowing upward when the above-mentioned electrode is energized goes through Electrochemical reaction, the above-mentioned column additionally includes ceramic/glass particles mixed with the wastewater to be treated, when the electrodes are energized, the wastewater undergoes electrochemical treatment and fluidized bed treatment composed of ceramic/glass particles, the impurities in the wastewater Separated and deposited in the bottom funnel of the storage tank, drained through the outlet. If desired, an optional alternative/further embodiment of the method as described herein may also include the step of injecting submicroscopic air bubbles in an upward direction through the column, In order to carry the suspended solids in the wastewater to be treated to float upwards, and then discharge them through the outlet set at the top of the column.

In the foregoing method of the present invention, when the fluidized bed is composed of activated carbon particles, due to the dissolved impurities are adsorbed on the surface of the activated carbon by physical-chemical adsorption, an effective effect is achieved. In addition, due to the fluidization of the wastewater to be treated effect, and the wastewater to be treated is simultaneously subjected to improved electrolytic treatment, which increases the turbulence of this wastewater, resulting in increased dispersibility and mass transfer and interfacial area.

When the fluidized bed is constructed using special forms of ceramic/glass spheres, they serve as the inert medium for the fluidization.

As mentioned above, the applicants have found that, while employing an improved electrolysis process, when the wastewater to be treated is also undergoing fluidization, the synergistic effect of this treatment improves the performance of the system, such as in terms of purification efficiency, certain refractory The removal rate of compounds such as phenols, and the removal rate of those compounds that are very low in concentration and therefore difficult to remove, can improve the performance of the electrolysis process itself by scraping the surface of the electrode to keep it updated all the time without any attachments, Increased turbulence in wastewater flow through the column increases dispersion and mass transfer, resulting in a more compact system.

The applicant has further discovered that by injecting gaseous oxygen/ozone bubbles into the waste water undergoing the above-mentioned combined treatment, it is possible to overcome some of the limitations of this combined treatment.

Accordingly, the present application provides a wastewater treatment method for purifying wastewater comprising flowing upwards through a column made of plastic having composite electrodes submerged in water the anodes of which are made of iron Composed of a mixture of aluminum and aluminum, the cathode is composed of iron alone, and the top of the above-mentioned column has a plastic storage tank with a funnel-shaped bottom. When the above-mentioned electrode is energized, the upwardly flowing wastewater undergoes an electrochemical reaction. It further includes activated carbon in the form of particles present in the wastewater to be treated. In the state of energizing the electrodes, the wastewater undergoes electrochemical treatment and fluidization composed of activated carbon particles. It is introduced from the bottom of the column under a predetermined pressure. Gaseous oxygen/ozone, whereby the wastewater undergoes a synergistic effect of electrochemical, oxidation, fluidization and dissolved air flotation treatments, impurities are separated from the wastewater and deposited in a funnel-shaped storage tank at the bottom, which is discharged through its outlet Walk.

In another embodiment, the present invention provides another wastewater treatment method for purifying wastewater comprising flowing wastewater upwardly through a column made of plastic without a submerged composite electrode, the above-mentioned The anode of the electrode is composed of a mixture of iron and aluminum, the above-mentioned cathode is composed of iron alone, and the top of the above-mentioned column has a storage tank made of plastic with a funnel-shaped bottom. When the above-mentioned electrode is energized, the waste water flowing upward undergoing an electrochemical reaction, the above-mentioned column further includes glass/ceramic particles present in the wastewater to be treated, and when the electrodes are energized, the wastewater undergoes electrochemical treatment and fluidized bed treatment composed of glass/ceramic particles, under a predetermined pressure , introduce gaseous oxygen/ozone from the bottom of the column, thereby making the wastewater undergo synergistic effects of electrochemistry, oxidation, fluidization and dissolved air flotation, and impurities are separated from the wastewater and deposited at the bottom as a funnel-shaped storage trough and drain it from its outlet.

The applicant observed that the electrochemical treatment of wastewater as proposed herein achieves the purification of the wastewater by the following physico-chemical phenomena:

(a) Electrochemical coagulation and flocculation of iron and aluminum occur at the composite electrode, and the iron and aluminum of the composite anode form iron and aluminum hydroxides, which can trap undissolved impurities due to their relatively small volume. Large, so they will react with certain dissolved impurities such as dyes to form chelated insoluble compounds in the form of "flocs", when a direct current of about 12-16 volts is passed through the wastewater, with the help of electrodes, according to Faraday's law, the composite anode goes into solution, resulting in the formation of hydroxides as described above. These hydroxides are more reactive than those produced by the traditional practice of dissolving aluminum and iron sulfates directly in water. Therefore, the purification efficiency of 'electro-flocculation' is much higher than that of general flocculation methods. Therefore, it shows greater versatility in removing multiple impurities from wastewater;

(b) Certain impurities are adsorbed on the hydroxide species by means of the Vanderwal forces;

(c) dissociation of water into free functional groups which react with impurities thereby converting them into harmless compounds;

(d) Oxidation of impurities by oxygen generated by electrolysis;

(e) some stable compounds are decomposed by the ozone introduced in the process;

(f) Impurities are reduced by the generated hydrogen.

(g) The gases emitted at the electrodes, almost in the DAF phenomenon, carry the flocculated impurities with them floating up to the top of the column.

The electrochemical dosage of iron and aluminum added to the waste water as a result of electrolysis can be in the range of about 50mg/l-700mg/l, depending on the type of impurity and the concentration level to be reduced to, similarly, as required, The current flowing is in the range of approximately 50-650 amps per liter of wastewater. The current density can be selected from 3-40 amps per square meter of total electrode area. In order to effectively remove almost all impurities such as suspended solids, COD, BOD, color, toxic substances, detergents, oil and grease, ammonia nitrogen, heavy metals, etc., the hydraulic retention time of wastewater in the electrolytic column is preferably about 1 minute- within 10 minutes. From the point of view of energy consumption and waste water treatment, the distance between electrodes is critical, and it should be in the range of 5mm-10cm.

When the electrolyzed liquid flows from the top of the column into the wider cross-section of the bottom of the funnel-shaped storage tank, impurities in the form of heavy flocs are deposited on the bottom of the storage tank under the action of gravity and are carried by the effluent. filter column. On the other hand, light impurities rise to the top with rising air bubbles and form a layer of "scum" on the hollow surface of the sump. The scum-like fluid was drained along with some "flocs" and it was found that when the blue-green "scum" and "flocs" collected at the top of the column and at the bottom of the sump were mixed with the raw sewage, Shows remarkable purification performance, presumably due to the adsorptive properties and the presence of unreacted metal hydroxides.

Preferably, the electrolyzed, flocculated wastewater from the bottom of the sump flows into another plastic column containing a polypropylene filter bag. Passage of the wastewater through the filter bag removes any flocculated impurities which are deposited as a filter cake on the inner surface of the bag. Subsequently, a clear and transparent, purified, watery effluent flows out from the bottom of the filter column.

As mentioned above, the fluidized bed can be composed of granular activated carbon. As a result, due to the physical-chemical adsorption, the dissolved impurities can be adsorbed on the surface of the activated carbon, and an effective treatment effect can be achieved. In addition, since the wastewater undergoes the modified electrolytic treatment in addition to the fluidized bed treatment, the turbulence of the wastewater increases, resulting in increased dispersion, mass transfer, and surface area at the interface. However, if only activated carbon in the form of a "fixed bed" is used to purify wastewater, it will be subject to the following limitations

i) Due to the small interface area of the fixed bed;

ii) In the saturated state, the amount of impurities adsorbed per unit weight of activated carbon is less;

iii) High pressure drop due to bed clogging/clogging and underutilization of the activated carbon bed;

iv) The activated carbon surface is not regenerated after saturation, so the spent activated carbon cannot be reused; it has to be discarded, which makes the method very expensive.

It was found that the combination of fluidized bed with modified electrolysis and "DAF" can remedy these limitations because:

Increased turbulence and area at the interface due to fluidization, where upwardly flowing gases and liquids keep the activated carbon particles in continuous swirling motion;

Oxidation and reduction of adsorbed impurities produced by oxygen/ozone and electrolysis respectively; no clogging/clogging of the bed due to continuous swirling motion of activated carbon particles.

As a result, greater cost-effectiveness, greater versatility, and greater efficiency can be achieved using activated carbon.

The characteristics of the invention can be better understood from the following description with reference to the accompanying drawings, presented by way of example, in which:

What Fig. 1 represents is the schematic diagram of an embodiment of realizing the method of the present invention, and this method is followed by filtration process after electrolysis;

Figure 2 represents a schematic diagram of another embodiment of the method for carrying out the invention, which includes an improved electrolysis process, as well as an oxidation process (by oxygen or by ozone) and a dissolved air flotation process;

What Fig. 3 represents is the schematic diagram of another embodiment of realizing the method of the present invention, and this method comprises improving electrolysis method and fluidized bed process (or adopts activated carbon particle, perhaps adopts ceramic/glass particle);

What Fig. 4 represented is the schematic diagram of another embodiment of the method of the present invention, and this method comprises the improved electrolysis method that combines with fluidized bed (or adopts activated carbon particle, or adopts ceramic/glass particle), and sprays to the water to be treated into gaseous oxygen/ozone.

In all of these figures, numerals 1-9 refer to the same parts which are generally used in the above-mentioned figures.

As shown in Figure 1, waste water is introduced through inlet 1, and this inlet 1 is arranged on the bottom of electrolysis column 2, and electrolysis column is made of plastics, as polyethylene, and this column 2 has a bottom at the top to be the storage tank 3 of funnel shape, It is also made of plastic such as polyethylene and has an outlet 4 for the purified water in the tank 3, an outlet 5 for the discharge of scum collected in the tank 3, and an outlet 6 for the overflow of the treated water. Also in this column 2 are two composite electrodes submerged therein, where the anode 7 consists of a mixture of iron and aluminum and the cathode 8 consists of iron alone. Denoted by 9 by a direct current power supply, with the electrodes energized, the wastewater passed through the bottom of the column 2 flows upwards while undergoing electrochemical reactions caused by the electrolysis process. As mentioned above, the impurities are separated by electrochemical reaction, deposited at the bottom of the storage tank 3, and are discharged at any time through the outlet 5, and the water purified in this step enters another column 10 made of plastic such as polyethylene through the outlet 4 In this column, there is a plastic filter bag 11 made of polypropylene, so that after the water passes through the above-mentioned filter medium, clear and purified water can be discharged through the outlet 12 arranged at the bottom of the above-mentioned filter column 10 .

As shown in Figure 2, waste water is introduced in the electrolytic column 2 through the inlet 1 that is arranged at the bottom of the electrolytic column 2. The resulting storage tank 3 has an outlet 4 for purified water, an outlet 5 for discharging scum collected in the storage tank 3, and an outlet 6 for overflow of treated water. The column 2 is immersed in two composite electrodes, wherein the anode 7 is composed of a mixture of iron and aluminum, while the cathode 8 is composed of iron alone. The incoming wastewater flows upward while undergoing electrochemical reactions caused by the electrolysis process. Including liquid oxygen, oxygen is passed into the column through the funnel-shaped bottom 11A of the column 2 at a certain pressure from the storage tank 10A (or ozone at a pressure of 35-45 psig from the ozone generator 10A, etc.). Thus, the wastewater undergoes a synergistic combination of electrochemical reactions, oxidation and dissolved air flotation as described above.

As mentioned earlier, the impurities separated by this joint treatment are deposited at the bottom of the storage tank 3 and are discharged at any time through the outlet 5, and the purified water passes through the outlet 4 into another tank made of plastic such as polyethylene. (as in the particular embodiment shown) a column 12A is provided inside which is provided a plastic filter bag 13A, for example made of polypropylene, so that after the water passes through the above-mentioned filter medium, it can pass through An outlet 14A provided at the bottom of the filter column 12A discharges clear purified water.

As shown in Figure 3, waste water is introduced in the electrolytic column 2 through the inlet 1 that is arranged at the bottom of the electrolytic column 2, and this column 2 is made of plastics such as polyethylene, and it has a funnel-shaped bottom at the top made of plastics such as polyethylene. A tank 3 made of ethylene with an outlet 4 for purified water, an outlet 5 for discharging scum collected in the tank 3, and an outlet 6 for overflow of treated water. There are two composite electrodes submerged in the column 2, wherein the anode 7 is composed of a mixture of iron and aluminum, while the cathode 8 is composed of iron alone, and the DC power supply is represented by 9. When the electrodes are electrified, pass The wastewater introduced at the bottom of column 2 flows upward while undergoing electrochemical reactions caused by the electrolysis process. Also in column 2 are particles of activated carbon (or ceramic/glass beads in granular form) mixed with the wastewater to be treated (indicated by 10B). As mentioned above, this will produce a synergistic effect of the combination of electrochemical reaction and fluidized bed, and enable the efficient separation of impurities from wastewater. The impurities separated by the combined action of electrochemical reaction and fluidization deposit on the bottom of the storage tank 3 and are discharged at any time through the outlet 5, while the water thus purified is preferably passed through the outlet 4 (as shown in the example given. shown) into another column 11B made of plastic such as polyethylene, in which a plastic filter bag 12B made of polypropylene is provided, after the water passes through the above-mentioned filter medium, it passes through the column 11B set on the above-mentioned filter An outlet 13B at the bottom discharges clear purified water.

As shown in Figure 4, waste water is introduced in the electrolytic column 2 through the inlet 1 that is arranged at the bottom of the electrolytic column 2, and this column 2 is made of plastics such as polyethylene, and it has a funnel-shaped bottom at the top made of plastics such as polyethylene. A storage tank 3 made of ethylene with an outlet 4 for the purified water, an outlet 5 for discharging the scum collected in the storage tank 3 and an outlet 6 for allowing the treated water to overflow. Also immersed in this column 2 are two composite electrodes in which the anode 7 is composed of a mixture of iron and aluminum, while the cathode 8 is composed of iron alone. The wastewater introduced at the bottom flows upwards while undergoing electrochemical reactions caused by the electrolysis process, and in column 2 there are activated carbon particles (or ceramic/glass beads in the form of particles) mixed together with the wastewater to be treated (denoted by 10C). At the same time, under a certain pressure, gaseous oxygen/ozone is passed from the gas source 11C through the bottom 12C of the column 2, so that the activated carbon particles (or ceramic/glass pellets in the form of particles) mixed with the waste water to be treated will no longer Keep the bed fixed. As mentioned above, this will produce a synergistic combination of electrochemical reactions, fluidization, oxidation and dissolved air flotation, and impurities can be effectively separated from the wastewater. The impurities separated by the combined treatment as described above are deposited at the bottom of the sump 3 and are readily discharged through the outlet 5, while the water thus purified is preferably passed through the outlet 4 (shown as 15 in the illustrated embodiment) to another In a column 12C made of plastic such as polyethylene, there is no plastic filter bag 13C made of polypropylene in the column 12C. After the water passes through the above-mentioned filter medium, it is passed through the outlet 14C provided at the bottom of the above-mentioned filter column 12C. Clear purified water is discharged.

In these embodiments of the method of the present invention, whether modified electrolysis is combined with or without oxidation/dissolved air flotation, the preferred dimensions of the system and the preferred conditions employed in these embodiments are as follows:

Height of electrolytic column (cylindrical): 21/2′～6′-0″

Column diameter: 6'～4-1/2'

Sacrificial positive dose: 50～700mg/l

Average area velocity of water: 0.2～1M/S

Wastewater residence time in the column: 3 to 15 minutes

Furthermore, in those embodiments of the process of the present invention, the improved electrolysis method combined with the fluidized bed method, with or without oxidation (by gaseous oxygen or ozone), is preferred for the system in these embodiments The dimensions and the preferred conditions used are as follows:

a) Voltage: 12-24 volts;

b) Current: 20～300A/kl/hour depends on impurities;

c) Electrode spacing: 1″～3″

d) Current density based on the total surface area of the electrode: 0.5 ~ 65MA/cm ² ;

e) Dose of sacrificial anode: 20～250mg/l waste water

f) Column diameter: 6″～5′-0″;

g) Column height: 21/2'～5';

h) Particle size of activated carbon particles: 3-8mm;

i) The depth of the fluidized bed: 50-70% of the column height;

j) The average area flow rate of wastewater in the column: 0.15～0.5M/S;

k) Hydraulic retention time in the column: 0.25～420S;

l) The number of solid particles (activated carbon particles) per unit weight of wastewater: 20 ~ 85gms/100gm wastewater

The performance comparison of different embodiments of the present invention is listed in the table below.

It should be clear that within the scope of the above, various changes are possible in the practice of the method of the present invention, which are all within the scope of the appended claims.

Claims (26)

1. A waste water treatment method for purifying waste water and making it circulate, the method comprising making the waste water to be treated flow upward through a column made of plastic, in which a composite electrode submerged in water is provided, and the anode of the above-mentioned electrode is formed by Composed of a mixture of iron and aluminum, while the cathode is composed of iron alone, the column has a plastic storage tank with a funnel-shaped bottom at its top. A chemical reaction whereby the impurities in the wastewater are separated and removed from the top of the column, and the water thus purified is then filtered through a filter medium, optionally, if so desired, in the wastewater During electrolysis, submicroscopic air bubbles are injected upwards through the column to carry the suspended solids in the wastewater to be treated upwards during treatment so that they can be discharged through an outlet located at the top of the column. 2. A wastewater treatment method for purifying wastewater, the method comprising making the wastewater to be treated flow upward through a column made of plastic, in which a composite electrode submerged in water is provided, and the anode of the above-mentioned electrode is made of iron and Composed of a mixture of aluminum, while the cathode is composed of iron alone, the column has a plastic storage tank with a funnel-shaped bottom at the top, and gaseous oxygen is introduced into the water from the bottom of the column at a predetermined pressure. Oxygen bubbles flow upwards through the wastewater, and in the case of energizing the electrodes, the wastewater undergoes an electrochemical reaction, thereby subjecting the wastewater to a synergistic combination of electrochemical, oxidation and dissolved air flotation treatments, from which Impurities separated from waste water are discharged from the top of the column after being deposited in a funnel-shaped storage tank provided at the top of the column, and purified water is discharged from the top of the above storage tank. 3. A wastewater treatment method for purifying wastewater, the method comprising making the wastewater to be treated flow upward through a column made of plastic, in which a composite electrode submerged in water is provided, the anode of the above electrode is made of iron and It is composed of a mixture of aluminum, while the cathode is composed of iron alone. The top of the column has a plastic storage tank with a funnel-shaped bottom. Under a predetermined pressure, gaseous ozone is introduced into the water from the bottom of the column. Ozone bubbles are made to flow upwards through the wastewater, and in the case of energizing the electrodes, the wastewater undergoes an electrochemical reaction whereby the wastewater undergoes a synergistic combination of electrochemical, oxidation and dissolved air flotation treatments, due to this combined treatment, Impurities separated from waste water are deposited in a funnel-shaped storage tank at the top of the column, and then drained from the top of the column, and purified water is discharged from the top of the above storage tank. 4. A wastewater treatment method for purifying wastewater, the method comprising making the wastewater to be treated flow upward through a column made of plastic, in which a composite electrode submerged in water is provided, the anode of the electrode is made of iron and Consisting of a mixture of aluminum, while the cathode consists of iron alone, the top of the column has a sump made of plastic with a funnel-shaped bottom, so that the upwardly flowing waste water undergoes an electrochemical reaction when the above-mentioned electrodes are energized , in the above-mentioned column, there is also activated carbon in the form of particles in the wastewater to be treated, so that when the above-mentioned electrodes are energized, the wastewater is subjected to electrochemical treatment and fluidized bed treatment formed by activated carbon particles. The impurities are separated and deposited into the funnel-shaped storage tank at the bottom, and discharged through the outlet. 5. A wastewater treatment method for purifying wastewater, the method comprising making the wastewater to be treated flow upward through a column made of plastic, in which a composite electrode submerged in water is provided, and the anode of the above-mentioned electrode is made of iron and Composed of a mixture of aluminum, while the cathode is composed of iron alone, the top of the column has a plastic storage tank with a funnel-shaped bottom. When the above-mentioned electrodes are energized, the upwardly flowing wastewater undergoes an electrochemical reaction. The above-mentioned column further includes ceramic/glass particles mixed with the waste water to be treated. When the above-mentioned electrodes are energized, the waste water is subjected to electrochemical treatment and fluidized bed treatment formed by the ceramic/glass particles. In the waste water The impurities are separated and deposited into the funnel-shaped storage tank at the bottom, and discharged through the outlet. 6. A wastewater treatment method for purifying wastewater, the method comprising making the wastewater to be treated flow upward through a column made of plastic, in which a composite electrode submerged in water is provided, and the anode of the electrode is made of iron and Consisting of a mixture of aluminum, while the cathode consists of iron alone, the top of the column has a sump made of plastic with a funnel-shaped bottom, so that the upwardly flowing waste water undergoes an electrochemical reaction when the above-mentioned electrodes are energized , the above-mentioned column further comprises activated carbon in the form of particles present in the waste water to be treated, whereby, in the case of energizing the above-mentioned electrodes, the waste water undergoes electrochemical treatment and fluidized bed treatment consisting of active particles, at a predetermined pressure Next, gaseous oxygen/ozone is introduced from the bottom of the column, whereby the wastewater undergoes a synergistic combination of electrochemistry, oxidation, fluidized bed and dissolved air flotation, and impurities are separated from the wastewater and deposited at the bottom as In the funnel-shaped storage tank, it is discharged through the outlet. 7. A wastewater treatment method for purifying wastewater, the method comprising making the wastewater to be treated flow upward through a column made of plastic, in which a composite electrode submerged in water is provided, the anode of the electrode is made of iron and Consisting of a mixture of aluminum, while the cathode consists of iron alone, the top of the column has a sump made of plastic with a funnel-shaped bottom, so that the upwardly flowing waste water undergoes an electrochemical reaction when the above-mentioned electrodes are energized , the above-mentioned column further includes glass/ceramic particles mixed together with wastewater to be treated, and in the case of energizing the electrodes, the wastewater undergoes electrochemical treatment and fluidized bed treatment composed of glass/ceramic particles, under a predetermined pressure, from The bottom of the column introduces gaseous oxygen/ozone, so that the wastewater undergoes a combination of electrochemistry, oxidation, fluidization and dissolved air flotation to separate impurities from the wastewater and deposit them in a funnel-shaped storage tank at the bottom , discharged through its outlet. 8. A method as claimed in any one of claims 2-7, characterized in that the water thus purified is passed through a filter medium made of a plastic such as polyethylene Made of column composition. 9. The method according to claim 4 or 5, characterized in that the submicroscopic air bubbles injected upward pass through the column, carrying the suspended solids in the wastewater to be treated to float upwards, so as to be discharged from the outlet provided at the top of the column . 10. The method of claim 3, characterized in that ozone is introduced at a pressure of 35-45 psig, which increases the effectiveness of the purification process by oxidation of certain impurities and by the resulting "DAF" phenomenon. 11. The method according to any one of claims 1-3, characterized in that the conditions used to realize these methods are as follows: The height of the electrolytic column (cylindrical): 21/2′～6′-0″ Column diameter: 6'～4-1/2' Sacrificial positive dose: 50～700mg/l Horizontal average area velocity: 0.2～1M/sec Wastewater residence time in the column: 3 to 15 minutes 12. The method according to claim 11, characterized in that the current between the electrodes is in the range of 50-650A/kl waste water, the current density is selected at 3-40 A/m2 of the total surface area of the electrodes, and the current between the electrodes The distance is within the range of 5 mm to 10 cm, and the above parameters can be selected according to needs. 13. The method according to any one of claims 4-7, characterized in that the conditions used to implement the method are as follows: a) Voltage: 12-24 volts; b) Current: 20～300A/kl/hour depends on impurities; c) Electrode spacing: 1″～3″ d) Current density based on the total surface area of the electrode: 0.5 ~ 65MA/cm ² ; e) Dose of sacrificial anode: 20-250mg/l waste water; f) Column diameter: 6″～5′-0″; g) Column height: 21/2'～5', h) Particle size of activated carbon particles: 3-8mm; i) The depth of the fluidized bed: 50-70% of the column height; j) The average area flow rate of wastewater in the column: 0.15～0.5M/S; k) Hydraulic retention time in the column: 0.25～420S; l) The number of solid particles (activated carbon particles) per unit weight of wastewater: 20 ~ 85gms/100gm wastewater 14. A waste water treatment equipment for purifying waste water, which comprises a column made of plastic or any other non-conductive material, in which there is a composite electrode submerged in water, the anode of which is made of a mixture of iron and aluminum , while the cathode is composed of iron alone, and the cathode is composed of iron alone, and the top of the above-mentioned column is provided with a storage tank with a funnel-shaped bottom, which is made of plastic or any other non-conductive material. When the electrodes are energized, the upwardly flowing wastewater undergoes an electrochemical reaction through an inlet at the bottom of the set column, a funnel-shaped sump at the bottom that is used to drain away impurities and scum that accumulates in the sump. outlet, an outlet for the overflow of treated water, and an outlet for purified water so treated, which outlet is connected to a filter medium, and the bottom of the column is optionally provided with a submicroscopic air injection A device for air bubbles that causes air bubbles to flow upwards through the column during wastewater electrolysis. 15. A waste water treatment equipment for purifying waste water, which comprises a column made of plastic or any other non-conductive material, in which there is a composite electrode submerged in water, and the anode of the electrode is composed of a mixture of iron and aluminum , while the cathode is made of iron alone, the top of the column is provided with a funnel-shaped bottom made of plastic or any other non-conductive material storage tank, in the case of electrification to the above-mentioned electrode, the The upwardly flowing waste water undergoes an electrochemical reaction through an inlet at the bottom, the bottom of which is a funnel-shaped sump with outlets for the removal of impurities and scum collected in the sump, outlets for the overflow of treated water, and an outlet for the purified water so treated, and including an oxygen source for introducing gaseous oxygen into the wastewater from the bottom of the column at a predetermined pressure during the electrolysis of the wastewater so that the oxygen bubbles pass through Wastewater flows upwards. 16. A waste water treatment equipment for purifying waste water, which comprises a column made of plastic or any other non-conductive material, in which there is a composite electrode submerged in water, the anode of which is made of a mixture of iron and aluminum , while the cathode is made of iron alone, and the top of the column is provided with a funnel-shaped bottom made of plastic or any other non-conductive material storage tank, in the case of energizing the above-mentioned electrodes, passing through the bottom of the column The upward flow of wastewater from the inlet undergoes an electrochemical reaction, and the bottom is funnel-shaped with an outlet for removing impurities and scum collected in the tank, an outlet for the overflow of treated water, and a An outlet for purified water so treated, and including an ozone source which, during electrolysis of wastewater, injects gaseous ozone into the wastewater from the bottom of the column at a predetermined pressure to bubble the ozone through the wastewater upward flow. 17. A waste water treatment equipment for purifying waste water, the equipment includes a column made of plastic or any other non-conductive material, in which there is a composite electrode submerged in water, the anode of which is composed of a mixture of iron and aluminum , while the cathode is made of iron alone. The top of the above-mentioned column is provided with a storage tank made of plastic or any other non-conductive material with a funnel-shaped bottom. When the above-mentioned electrode is energized, the The upward flow of wastewater through the inlet of the tank undergoes an electrochemical reaction, and the bottom is a funnel-shaped tank with an outlet for draining away impurities and scum collected in the tank, an outlet for the overflow of treated water, and An outlet for the purified water thus treated, in the said column in the wastewater to be treated there is also activated carbon in the form of granules, whereby the wastewater is subjected to electrochemical treatment and the activated carbon is The fluidized bed treatment of particle formation separates the impurities in the wastewater and deposits them in the bottom of the funnel-shaped storage tank, which is discharged through the outlet. 18. A waste water treatment equipment for purifying waste water, which comprises a column made of plastic or any other non-conductive material, in which there is a composite electrode submerged in water, the anode of which is made of a mixture of iron and aluminum , while the cathode is made of iron alone. The top of the above-mentioned column is provided with a storage tank made of plastic or any other non-conductive material with a funnel-shaped bottom. When the above-mentioned electrode is energized, the The upward flow of wastewater through the inlet of the tank undergoes an electrochemical reaction, and the bottom is a funnel-shaped tank with an outlet for removing impurities and scum collected in the tank, an overflow outlet for treated water, and a Outlet for the purified water thus treated, in said column there are also ceramic/glass particles in the waste water to be treated, whereby in case of energization of said electrodes, the waste water undergoes electrochemical treatment and is made of ceramic/glass particles The formed fluidized bed treatment separates the impurities in the wastewater and deposits them in the funnel-shaped storage tank at the bottom, and discharges them through the outlet. 19. A waste water treatment equipment for purifying waste water, which comprises a column made of plastic or any other non-conductive material, in which there is a composite electrode submerged in water, the anode of which is made of a mixture of iron and aluminum , while the cathode is made of iron alone. The top of the above-mentioned column is provided with a storage tank made of plastic or any other non-conductive material with a funnel-shaped bottom. When the above-mentioned electrode is energized, the The upward flow of wastewater through the inlet of the inlet undergoes an electrochemical reaction. The bottom is a funnel-shaped storage tank with an outlet for removing impurities and scum collected in the storage tank, an overflow outlet for treated water, and a At the outlet of the purified water thus treated, there is also activated carbon in the form of particles in the waste water to be treated in the above-mentioned column, and the device also includes a source of gaseous oxygen/ozone, which, at a predetermined pressure, The source feeds gaseous oxygen/ozone into the wastewater from the bottom of the column, so that the wastewater undergoes a combination of electrochemical, oxidation, fluidization and dissolved air flotation treatments to separate impurities from the wastewater and deposit In the funnel-shaped bottom of the storage tank, it is discharged through its outlet. 20. A wastewater treatment device for purifying wastewater, which includes a column made of plastic or any other non-conductive material, in which there is a composite rain electrode submerged in water, and the anode of the electrode is made of a mixture of iron and aluminum The cathode is composed of iron alone, and the top of the above-mentioned column is provided with a storage tank made of plastic or any other non-conductive material with a funnel-shaped bottom. When the above-mentioned electrode is energized, the The upward-flowing wastewater undergoes an electrochemical reaction through an inlet at the bottom, a funnel-shaped tank with an outlet to drain away impurities and scum that collects in the tank, an overflow outlet for treated water, and a Outlet for the purified water thus treated, in the above-mentioned column there are also ceramic/glass particles in granular form within the waste water to be treated, the device also includes a source of gaseous oxygen/ozone, at a predetermined pressure, the The gaseous oxygen/ozone source introduces gaseous oxygen/ozone into the wastewater from the bottom of the column, so that the wastewater undergoes a synergistic effect of electrochemical, oxidation, fluidization and dissolved air flotation to separate impurities from the wastewater come out, and deposit in the bottom of the funnel-shaped storage tank, discharged through its outlet. 21. An apparatus as claimed in any one of claims 15-20, characterized in that the purified water outlet of the column is connected to the filter medium. 22. Apparatus as claimed in claim 21, characterized in that the filter medium consists of a column containing polypropylene filter bags and made of a plastic such as polyethylene. 23. Apparatus as claimed in any one of claims 14 to 16, characterized in that the following parameters are used: Electrolytic column height (cylindrical): 21/2′～6′-0″ Column diameter: 6″～4-1/2′ 24. Apparatus as claimed in any one of claims 17 to 20, characterized in that the following parameters are used: a) Electrode spacing: 1″～3″; b) Column diameter: 6″～5′-0″; c) Column height: 21/2'～5', 25. A wastewater treatment method for purifying wastewater substantially as herein described with reference to the accompanying drawings. 26. A waste water treatment plant for purifying waste water substantially as hereinbefore described and illustrated with reference to the accompanying drawings.

Images