MXPA00011935A

MXPA00011935A - Novel cells and electrodes and their use in the treatment of residual waters by electro-coagulation.

Info

Publication number: MXPA00011935A
Authority: MX
Inventors: A Tipton Gary
Original assignee: Arturo Carrasco Breton
Priority date: 2000-11-30
Filing date: 2000-11-30
Publication date: 2002-06-10
Also published as: AU2002219911A1; CA2430424A1; WO2002044092A1

Abstract

The present invention discloses an apparatus for the treatment of residual waters comprising: an electro-coagulation cell including insulating and fastening means, a cell upper lid, and a plurality of electrodes plates inserted within a non-conductive material jacket, with this the electrodes plates conjunct offers a minimum water resistance. An electro-coagulation cell including means for breaking with the laminar water flow and keeping the turbulence state throughout said cell. An electrodes plate's conjunct connected in parallel or in series, wherein said conjunct of electrodes plates having connections placed in such way that it is possible to interrupt and revert indistinctly the electric current. An electrodes plate's conjunct connected in parallel or in series, wherein it is possible to make a metal combination with the electric connections for the disinfection of treated water.

Description

NOVEL CELLS AND ELECTRODES FOR USE IN WASTEWATER TREATMENT BY ELECTROCOAGULATION.

TECHNICAL FIELD OF THE INVENTION: The present invention deals with cells and electrodes for treatment by electrocoagulation in wastewater.

BACKGROUND OF THE INVENTION: The present invention relates to the means to destabilize wastewater pollutants, come from industrial or municipal water. Suspended pollutants, emulsified or dissolved in the bodies of water, are destabilized and precipitated by the introduction of electric current to the aqueous medium by means of said means. The flow of waste water passes through the means which consist of cells and electrodes for electrocoagulation of pollutants.

As is well known in the present state of the art, the electrolytic treatment of liquids allows the separation of a wide range of contaminants such as: metals, protein solids, pathogenic organisms, emulsions of oils and fats, as well as unwanted substances between others. The electrolytic treatment in techniques prior to the present invention indicate a relative degree of success in the purification of wastewater, which consitutes in general terms the use of an electric field applied to a liquid, which is contained in a chamber for coagulate the contaminants contained in the liquid or to remove the impurities that are in the liquid. An example of said apparatuses and methods for the electrolytic treatment are those disclosed in the publication of the PCT patent application No. WO 9640591, wherein in said invention a flow of water containing contaminants is passed through polarized means, which have a potential electrical that is different from the ground potential, to be subsequently passed through an electrocoagulation chamber which includes a plurality of elongated electrodes or electrocoagulation plates, which have different electrical potentials between each of the plates. The cells have a plurality of holes to cause turbulence in the water flow and in this way increase the efficiency of the treatment by electrocoagulation. Although the apparatus of the present PCT might be suitable for its purpose, a disadvantage of such an apparatus is that the passage of water flow as it passes through the apparatus requires electrodes or electrocoagulation plates to withstand high water pressure to avoid in this way the electrocoagulation plates are plugged. By having to withstand a high water pressure, the electrocoagulation plates or electrodes must be built sufficiently robust in size and strength, thus limiting the number of plates in a given volume which reduces the area available for the electrocoagulation treatment.

Additionally electrocoagulation plates require a higher voltage in their connection line, in order to obtain the desired amperage in the electric field created by the plates, because the area of the surface is limited by the high water pressure. Electrocoagulation plates of a smaller size that withstand the pressure can be used, however the ability to maintain the desired amperage is sacrificed since the surface available for plates in an electrocoagulation device is directly related to the amperage that can be maintained . Additionally, the passage in the form of a tortuous path for the flow of water is a cause of problems, because the gases produced by the electrolytic reactions inside the chamber are trapped, thus causing the pressure between the plates to increase. Therefore the use of a high power pump should be used to overcome the natural tendency of the water flow to avoid plugging the electrocoagulation chamber.

Other examples of electrolytic apparatus and treatments are disclosed in the PCT patent application publication No. WO 9943617, wherein said invention refers to the conduction of the gases formed by the electrocoagulation process so that they ascend towards the water line thus achieving air to the atmosphere, also the solids can precipitate out of the current and be deposited in a secondary separation. It is described that any remaining solid can be removed as mud through a drain located at the bottom of the apparatus.

Said apparatus includes a cover for isolating the foam from the electrical connections of the plates and thereby preventing the formation of moisture. Said apparatus can be manufactured as an industrial unit, as a portable unit or as a domestic unit, where it can be operated in a controlled pressure environment, thus eliminating the use of a pump. Another mode is the adjustment of the voltage and amperage of the electric field within the reaction chamber by accommodating and selecting the plates, as these are necessary, where the input line of the voltage itself can be left as a constant, which eliminates the need to use an additional transformer. However, the present invention does not provide any self-cleaning means for the electrode plates, nor does it provide any means for directing the flow of water through the electrode plates and does not have any means to properly adjust the time for the application of the electric current in the electrodes.

PCT patent application WO 9817589, wherein said invention relates to an apparatus for the treatment of effluents, which includes a chamber having an inlet, an outlet and a plurality of electrodes that extend vertically in the chamber, also counting with an electrical supply connected to the electrode plates. The plurality of electrodes consists of a plurality of channels placed between the input and the output of the apparatus, wherein the electrical supply provides electricity of one polarity to the first set of electrodes and electricity to a second set of electrodes. As in the aforementioned PCT No. WO 9943617, the present patent application does not have any self-cleaning means for the electrode plates, nor does it provide any means to direct the flow of water through the electrode plates. and it does not count any means to properly adjust the time for the application of the electric current in the electrodes.

The present invention is directed to provide the use of cells and novel electrodes that are very useful for the treatment of electrocoagulation in wastewater by the following objectives: An object of the present invention is to provide a Vortex-type cap to the electrode assembly of the electrocoagulation plates in order to exert a directional pattern in the flow of the water to be treated and also to each of the electrode assemblies of the plate . With the establishment of a flow direction pattern, there is a break in the laminar flow pressure that is formed by the passage of the water flow in the form of sheets between the electrocoagulation plates, thus achieving a state of controlled turbulence between each set of electrodes from the entrance to the outlet of the water flow of the electrocoagulation plates.

Another objective of the present invention is to reverse the polarity of the electrodes at a predetermined time as a self-cleaning means for the electrode plates. To invert the polarity, plates with even numbering have been designed on the top of the electrocoagulation plates. In the lower part of the plates a similar connection of plates with odd numeration is made. "With this, each of the poles of the upper or lower part of the plates has odd or even connections in each of the respective poles of the plate. .

Another objective of the present invention is to provide the electrocoagulation cell with an upper cover of the cell in order to anchor the supports of the electrodes, to position them in the center of the cell jacket and achieve better operability in the cells. hydraulic installations, and a vortex-type bottom cover to obtain a water vortex with counter-clockwise direction, to ensure that the laminar flow of water is lost and to maintain the state of turbulence in the water flow through the entire cell.

Another object of the present invention is to use a combination of metals with electrical connections in series or in parallel, for the conversion of salts to chlorine solutions or for the disinfection of water.

Other objects will be apparent to the person skilled in the art in light of the following description and together with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS: FIGURE 1: Is a perspective drawing of the interior of the cell and set of electrocoagulation electrodes of the present invention.

FIGURE 2: It is a perpective drawing of the fully armed electrocoagulation cell of the present invention.

FIGURE 3: It is a perspective drawing of the interior of an alternate form of the cell and set of electrocoagulation electrodes object of the present invention.

DETAILED DESCRIPTION OF THE INVENTION: The present invention is based mainly on a set of novel electrode plates, inserted inside a jacket of non-conductive material which is usually constructed of plastic material and preferably of PVC material. Therefore, the set of electrodes has plates at the center of the set of a greater width with respect to the plates that, as they move away from the center, become thinner in width. Electrode plates are usually composed of metals that conduct electricity well, as is the case with iron and aluminum. In some treatments for wastewater by electrocoagulation the combination of plates made with metals such as stainless steel, copper, lead, zinc, titanium, among others is used. Metal alloys are also used in certain cases, as well as the use of conductive materials such as carbon, graphite, and others can be used in the present invention.

Figure 1 shows the interior of an electrocoagulation cell about 11 inches high by 3 inches wide, where the shoe for electrical connection is a positive pole (1), which is attached to a cable of rough use positive (2) and this same to a terminal (6). At the other end of the electrocoagulation cell there is another shoe for negative pole electrical connection (8), which is attached to a negative heavy duty cable (9) and this to a terminal on the side of the heavy duty cable negative (9) identical to the terminal (6). The nylamid screws (3) attached to the nylamid supports (4) on both sides of the electrocoagulation cell are used for the purpose of isolating and supporting the PVC top cover (17) of figure 2, wherein said supports of nylamid (4) are attached to the side of the set of electrode plates (11) and (12) by nylamid screws (5). Electrode plates (11) and (12) of Figure 1 are generally plates that go from 1/8 inch to 1/4 inch thick. Said plates are separated and isolated from each other by the insulating separators of nylamid (7) located on both sides of the electrode plates (11) and (12), and which consist of a nut and a screw (7) both of material of nylamid insulating and passing through the plates leaving a space between plate and plate (11) and (12), preferably 1/4 of an inch. Said nylamid insulating separator (7) consists of a screw (7) of 1/4 inch in diameter by 3 1/2 inch in length, wherein said screw is a nylon screw of 20 cords. The electrode plates (11) are connected in negative parallel, making a total of four negative electrode plates and the electrode plates (12) are connected in positive parallel, making a total of four positive electrode plates which require approximately 15 volts DC and 35 amperes of current. Said set of electrode plates (11) and (12) are connected to a connection band (10) in the upper part and a connection band (13) in the lower part. Said connecting bands (10) and (13) are conductive electrical connection bands of the same material as the set of electrode plates (11) and (12). The connection of both bands (10) and (13) to the set of electrode plates (11) and (12) is by means of arc welding. In the event that the set of plates (11) and (12) are these of materials such as carbon, graphite or any similar material, the connection is made by fusion. In the upper connection band (10) the set of electrode plates (11) of negative parallel are plates identified with odd numbers such as 1, 3, 5, 7, and 9. In the lower connection band (13) the set of positive parallel electrode plates (12) are plates identified with even numbers such as 2, 4, 6 and 8, however the number of electrode plates of the electrocoagulation cells object of the present invention may vary in number, according to the amount of water flow that needs to be treated. The identification of such connections with even and odd numbers has the purpose of connecting the even and odd poles to a current converter, not object of the present invention, to be able to interrupt and reverse indistinctively the current of the set of electrode plates, whether positive or negative. negative When an electric charge is transmitted through some electrode plate, a magnetic field is formed at each upper or lower end of the electrocoagulation cell. By interrupting and reversing the current of the poles, a variation in the intensity of the magnetic field is achieved, which has a direct effect on the charge of the particles of the contaminants contained in the water that pass through the electrocoagulation cell. Because the gases of hydrogen, oxygen, ozone and others are generated during the hydrolysis process on the surface of the electrode plates, the depolarization effect or changes in polarity causes the metal ions in the electrode plates they are released from the water molecules that have been depolarized or reformed from the hydrogen and oxygen molecules generated by the electrochemical reactions, and these molecules combine with other released pollutants to form larger particles, thereby creating an electrochemical flocculation effect.

The set of electrode plates (11) and (12) by their arrangement and distribution, offer a minimum resistance to water that passes through the electrocoagulation cell, achieving with this, the precipitation of solids product of the electrochemical coagulation are minimum, which in large quantities blocks the flow of water through the electrocoagulation cells.

Figure 2 is a perspective drawing showing the cell completely assembled with a PVC nipple (14) that allows the water to be treated, a sealed stud to avoid the passage of negative pole water (15), a sealed stud to prevent the passage of positive pole water (16) and PVC top cover (17). The PVC top cover (17) has the method of holding the electrode plates (11) and (12) by means of the nylamid supports (4) to place and completely center the set of electrode plates inside the fully sealed sleeve PVC (18) to prevent leakage or dripping of treated water. The PVC top cover (17) and the PVC Vortex bottom cover (19) are sealed to the PVC jacket (18) by means of threads and sealing material such as Teflon tape, nylon thread components and the like . The Vortex lower lid (19), has the modality of allowing the water to be treated through its cone shape with an angle of approximately 45 ° degrees of inclination in the upper part and of approximately 3 degrees of inclination in the preferably lower part, however said inclination can vary between an angle of 15 degrees of inclination to 60 degrees of inclination in the upper part of the cone and of 2 degrees of inclination to 7 degrees of inclination in the lower part of the cone . Said inclination of the vortex cone (19) varies according to the flow pressure of the water passing through the electrocoagulation cell of Figure 2. The minimum pressure required is approximately 9 Kg / cm2 and the maximum pressure is approximately 60 Kg / cm2. The flow of water to be treated when entering through the lower Vortex type lid (19) causes a water whirl with an anti-clockwise direction in order to ensure that the laminar flow of the inlet water is broken and maintained in this way a state of turbulence in the flow of water throughout the passage through the electrocoagulation cell object of the present invention.

Figure 3 is another embodiment of the present invention and consists of the union of three cells 11 inches long by 3 inches wide of Figure 1 and 2, where the difference is that the set of electrode plates are connected serially. However, the voltage is three times higher than in the 11-inch diameter cell and connected in parallel. Therefore, the modality of Figure 3 requires 45 volts DC and 35 amperes of electric current. Therefore, the efficiency of this modality increases up to approximately 300 percent, due to the following factors: to) . The contact time with the electrode plates (29) and (31) is tripled. b) The residence time in the treatment area for a given volume is tripled. c) The number of electrodes required to deliver the same volume of water is approximately 67% lower due to the use of the series configuration (29) and (31) of the electrode assembly. d). A state of high turbulence is maintained while the water passes through each set of electrodes (29) and (31).

The modifications of the present embodiment include the same accessories of figure 2, such as a PVC jacket (18), a PVC top cover (17) and a PVC Vortex type bottom cover (19). Also as shown in the drawing of Figure 3, the rest of the accessories such as the heavy-duty pole-positive cable (20), the nylamid screws (21), the nylamid supports (22), the terminal (24) ), the nylamid screws (23) for the support (22), the nylamid electrode plate separators (25), the heavy-duty pole negative cable (27), the upper connection band (28), the lower connection band (30), are the same elements of the present invention. The changes made in the present modality does not include changes that come out or expand with respect to the present unit of the invention, because they are not substantial changes that modify or alter the spirit of the invention. The terminal (26) is optional, the changes of the set of electrode plates instead of being connected in parallel pass to an alternating connection in series (29) and (31), and the lower terminal (32) is with the object to connect some other series if necessary.

Claims

CLAIMS:

1. - An apparatus for the treatment of wastewater comprising: An electrocoagulation cell including insulating and holding means, a top cover of the cell, a plurality of electrode plates inserted in such a way inside a jacket of non-conductive material , whereby the set of electrode plates offer a minimum resistance to water. An electrocoagulation cell including means for breaking the laminar flow of water and maintaining the state of turbulence throughout said cell. A set of electrode plates connected in parallel or in series, wherein said set of electrode plates have connections arranged in such a way that it makes it possible to interrupt and reverse the electric current indistinctly. A set of electrode plates connected in parallel or in series where a combination of metals can be made with the electrical connections for the disinfection of the treated water.

2. - An electrocoagulation cell according to claim 1, wherein means of insulating and fastening material are comprised, such as supports, spacers and preferably nylamid fastening means on both sides of the electrocoagulation cell where said supports are attached to the side of the electrocoagulation cell. set of electrode plates by screws of insulating material, preferably of nylamid; preferably nylamid insulating separators that pass through the electrode plates, leaving a gap between plate and plate of approximately 1/4 inch.

3. - An electrocoagulation cell according to claim 1, wherein the nylamid spacers consist of a nut and screw preferably of nylamid of about 1/4 inch in diameter by about 3 1/2 of an inch in length, wherein said screw can be of any other insulating material and from approximately 5 to 40 cords or threads, preferably 20 cords or threads.

. - An electrocoagulation cell according to claim 1, wherein the thickness of the set of electrode plates ranges from 1/8 of an inch to 1/4 of an inch.

5. - An electrocoagulation cell according to claim 1, wherein the size of the electrocoagulation cell is about 20 inches high by 7 inches wide, and where it preferably has a size of 11 inches high by 3 inches wide.

6. - An electrocoagulation cell according to claim 1, wherein the set of electrode plates in the electrocoagulation cell can vary in number according to the needs of wastewater treatment.

7. - An electrocoagulation cell according to claim 1, wherein the set of electrocoagulation plates require an electric current of approximately 10 volts DC to approximately 55 Volts DC and from approximately 20 amperes to 45 amperes, where preferably 15 volts DC are used in parallel, 45 volts DC in series and 35 amperes indistinctly.

8. - An electrocoagulation cell according to claim 1, wherein the set of electrode plates both parallel and in positive and parallel series and in negative series are identified with the odd and even classification interchangeably to be able to anticipate and deliberately interrupt and revert indistinctly the electric current transmitted to the set of electrode plates.

9. - An electrocoagulation cell according to claim 1, wherein the lower Vortex type plastic lid of the cell has the modality of allowing the entrance of the water to be treated through its cone shape with an angle of approximately 45 ° degrees of inclination in the upper part and the approximate 3 ° degree of inclination in the lower part preferably, however said inclination may vary between an angle of 15 ° degrees of inclination to 60 ° degrees of inclination in the upper part of the cone and of 2 or degrees of inclination at 7 degrees of inclination at the bottom of the cone.

10. - An electrocoagulation cell according to claim 1, wherein the minimum required pressure is about 9 Kg / cm2 and the maximum pressure is about 60 Kg / cm2.

11. - An electrocoagulation cell according to claim 1, wherein the flow of the water to be treated when entering through the Vortex-type lower cover causes a water vortex with a counter-clockwise direction in order to ensure that the laminar flow of the Inlet water is broken and thus a state of turbulence in the water flow is achieved throughout the passage through the electrocoagulation cell.