Water treatment device

Abstract

The present invention provides a modular water treatment device for a water treatment system and ribs therefor. The modular water treatment device includes two or more ribs arranged to form at least a part of a container, and one or more separators arranged between adjacent ribs. A water treatment system is also described, which system includes a water tank having an inlet for supplying sewage, and one or more modular water treatment devices located within the water tank, the water treatment devices including one or more electrodes and a power source operably connected to the electrodes. A method of constructing a modular water treatment device for a water treatment system and a method of operating the water treatment device are also provided.

Description

Technical Field

[0001] The present invention relates to a water treatment device, a system including the water treatment device, a method of constructing the water treatment device, and a method of operating the water treatment device. Background Art

[0002] It is well known that contaminated water is treated by various methods, including electrochemical treatment, in which an electric current is passed through the contaminated water to induce reactions to remove pollutants from the water.

[0003] Electrochemical oxidation systems for water treatment typically face the fact that water has low conductivity, resulting in high cell voltages and thus a high-energy, high-cost process. In addition, direct electrochemical oxidation only occurs when pollutants come into contact with the electrodes, meaning that these systems are highly limited by mass transfer when used to treat low-concentration and trace pollutants. This piecemeal oxidation can lead to the formation of decomposition products that are sometimes more toxic than the original pollutants. To address these issues, the electrode-electrode gap is made as narrow as possible, typically 1 - 5 mm or less. This reduces the cell voltage, especially when high flow rates are used within the system to create turbulence. However, the lower residence time and the formation of decomposition products mean that the system will need to recycle the wastewater to be treated multiple times before obtaining discharge permits. The small cell gap results in the need to use many cells (usually assembled in series) within the system to handle higher flows. This leads to an excessive voltage across the combined cells, thus requiring protection of the operator from electric shock. In addition, the high flow rate through the cells is achieved by high-pressure pumps, meaning that robust cells are required, which in turn results in costs. Electrochemical systems also require the cells to be electrically isolated from each other, except through a planned circuit path, which demonstrates the need for high tolerances during processing and thus results in high cell costs.

[0004] Although traditional electrochemical systems for treating water have many benefits, the above problems indicate that there is a need to address sealing and short-circuit issues, which result in high costs.

[0005] Another approach is to use a highly conductive material between the electrodes, which can act as an adsorbent to concentrate pollutants and also as a three-dimensional electrode. The high conductivity results in low cell voltages, thus forming a low-energy, low-cost system, and the concentration of organic matter on the adsorbent surface eliminates mass transfer problems. By using a particle bed, low flow rates can be used to provide a single-channel system. However, the highly conductive material increases the risk of short circuits and scale-up, and many cells still need to be assembled in series.

[0006] The present invention aims to solve at least one of the above problems. Summary of the Invention

[0007] A first aspect of the present invention relates to a modular water treatment device for a water treatment system, comprising: two or more ribs arranged to form at least part of a container, and one or more separators arranged between adjacent ribs.

[0008] According to a second aspect of the present invention, there is provided a rib for a water treatment system according to the first, third, fourth or fifth aspect of the present invention.

[0009] The device composed of modular components allows for the simple construction of a device of any desired size to fit the system being designed. Using ribs to form at least part of the container means that the size of the container can be easily adjusted by changing the number of ribs that make up the device as needed. For example, a very small device may only contain two ribs, while a large device may contain 20 or more ribs. In this way, a device including two ribs can have a single membrane located at the interface of the two ribs, while a device including, for example, four ribs can include one, two or three separators.

[0010] The said or each separator may be located between the opposing faces of adjacent ribs (i.e., within the interface region) so that it remains in place between the ribs. Preferably, a separator is provided between each set of ribs, but it is also conceivable that in some cases, no separator may be provided between some pairs of ribs. Desirably, the volume of each region or compartment between adjacent membranes is preferably greater than in the case where a separator is provided between each pair of ribs.

[0011] There may be gaskets or other sealing means between the ribs to prevent liquid leakage between the ribs and thus prevent short circuits. The sealing means may include, for example, silicone. The ribs may be configured to provide a leak-proof seal in the absence of gaskets or other sealing means. The ribs may be glued, solvent-bonded or welded together, and / or may be clamped together. This eliminates the possibility of leakage and / or short circuits. Optionally or additionally, the ribs may be mechanically connected together. For example, the ribs may include complementary mating parts that engage with one or more adjacent ribs. The mating parts may include complementary male and female mating parts. Such mating parts may provide greater structural strength and / or provide a bending seal to further reduce the possibility of leakage through the joints between adjacent ribs. In addition, the membrane may be arranged between the mating parts to provide a greater contact area between the ribs and the membrane, making it more difficult to pull the membrane out between the ribs.

[0012] The at least one separator may be a membrane, optionally an ion exchange membrane. The separator may be semi-permeable and / or porous, or by using an ion exchange membrane (such as Nafion TM)Operate by transferring ions. One or more separators divide the processing area into separate compartments. The edges of each separator may terminate between adjacent ribs in which it is disposed, such that a portion of the interface area does not contain the separator. Alternatively, the separator may extend across the entire interface area and even beyond the interface area. One or more separators are preferably non-conductive. The separator allows ions to pass through, but inhibits or blocks the passage of water. Suitable separator materials include any non-conductive material that allows ions to pass through but inhibits or blocks the passage of water and / or contaminants.

[0013] The ribs can be hollow. In other words, each rib can define an internal space without material. The ribs can be tubular (i.e., having open ends and a hollow interior). This reduces the weight of each rib and the entire modular water treatment device. This also reduces the amount of material required and improves manufacturing efficiency. The hollow ribs also allow the structure of the container to provide channels through which water can pass, thereby reducing or eliminating the need to provide additional piping. This simplifies the construction of the container assembly and reduces costs. The hollow rib cross-section can provide a flow distribution mechanism for the inflow into the cell.

[0014] The ribs can form the base and side walls of the container. This eliminates the burden of installing other components to form the container. In a small system, the ribs can act as a flow distributor and also as the container itself.

[0015] The ribs can be substantially U-shaped. This shape results in a container with an open top and a constant cross-sectional area, and devices of any length can be constructed simply by changing the number of ribs in the device. In addition, the container formed by the U-shaped ribs can have a flat base that, when placed on a horizontal surface, allows it to stand without relying on a support. Thus, the rib can include substantially parallel arms that extend substantially vertically and a substantially horizontal base that connects the two arms. Each rib can include a single-piece, preferably continuous tube, or can include one or more parts connected together. The container can have an open top that facilitates access to the internal space of the container for adding or removing materials (e.g., sewage, purified water, adsorbent, exhaust gas), inspection, maintenance, and repair. The ribs are preferably self-supporting so that they can retain liquid within the water treatment device without external support. Of course, this does not exclude providing external support if needed.

[0016] By ensuring that the ribs are hydraulically connected, a single feed into one of the ribs will be distributed throughout the rib and allow inflow to the bottom of the cell. The ribs can be hydraulically / fluidly connected by openings that allow fluid flow between adjacent ribs. Such connections can be made before, during, or after connecting the ribs.

[0017] One or more separators preferably extend between the arms and extend downwardly to the base. One or more separators may extend partially upwardly into the arms, all the way to the top of the arms, or may even extend above the top of the arms. In this way, the membrane divides the device into a plurality of compartments. Thus, the one or more separators prevent any conductive carbon-based adsorbent material contained in the compartments from entering adjacent compartments other than through the one or more separators. By sealing the compartments (except at the top), the possibility of electrical connection between the cells is eliminated, eliminating the possibility of short circuits and leaks.

[0018] Of course, other shaped ribs can be used to produce the modular water treatment device. Generally, each rib is elongated and has at least one curve or bend along its length. This ensures that once arranged face-to-face (the long faces of adjacent ribs opposing each other), a space is defined within at least one curve or bend (i.e., the container). A mixture of ribs can be used to fabricate a container having a variable cross-section along its length. By using different cross-sections, a device of any desired shape can be constructed. The ribs can include two substantially 90-degree elbows to form a U-shape. It will be appreciated that elbows greater than or less than 90 degrees can also be considered as long as the bend defines a space for containing water. There can be more than two elbows.

[0019] The ribs can be configured to engage with adjacent ribs to form a fluid seal. This allows the container to be in direct contact with a liquid (such as sewage), while maintaining a separation between the liquid inside the container and the liquid outside the container.

[0020] In some embodiments, engagable ribs form a ring, producing a container adapted to be immersed in a liquid. The container can be equipped with a lid to enclose the internal space defined by the ribs and the lid. The optional lid can be sealed or unsealed.

[0021] The ribs can include plastic. It is well known that plastic is used in electrochemical water systems due to its corrosion resistance, good strength-to-weight ratio, and being an electrical insulator. Plastic is particularly suitable for the modular water treatment device of the present invention because its easy-to-process nature makes it suitable for large-scale manufacturing methods. Other materials can be used where applicable. Other materials such as aluminum can be used, but additional electrical insulation needs to be provided to prevent short circuits and hazards to the operator. Plastic can be easily extruded on-site to form ribs of the desired shape, which means that the component material can be transported in a substantially straight length to maximize the amount of material transported within a given volume. This is particularly advantageous for transporting single containers as these containers can take up a large volume within the transport vehicle.

[0022] The ribs may comprise square tubes, preferably plastic square tubes. Such materials are widely available and a range of existing tools can be used to manufacture such ribs, reducing tooling costs and complexity. The square tubes can have any cross-sectional shape, but a square or rectangular cross-section is preferred as they provide a flat mating surface between adjacent ribs.

[0023] The ribs may include grooves to accommodate one or more membranes. This divides the interface area into a membrane retention area and an area where adjacent ribs are in direct contact. Such grooves prevent the membrane portion from extending into the interface area in the event of rib bending. The grooves have sufficient depth and width to securely hold the membrane without interfering with rib contact. It should be understood that even with the grooves, the cross-section of the rib can still be described as square or rectangular as these shapes define the general cross-sectional shape of the rib.

[0024] The ribs may be configured to allow fluid flow into the treatment zone defined by the container. Contaminated water must be able to enter the treatment zone for treatment. By providing a means of controlling the flow rate of the sewage entering the treatment zone through the wall of the container, the need to provide additional equipment (such as pipes) to affect such flow is avoided, simplifying the modular water treatment device. Additionally, since the liquid to be treated is provided through the hollow ribs, the flow distribution into the device is more uniform, and thus the distribution of the sewage is more uniform.

[0025] Fluid flow into the treatment zone may pass through the internal space of the ribs. This may also require at least one of the ribs to include an opening in the surface in contact with the treatment zone. Alternatively, openings may be provided in one or more surfaces in contact with the external space. This flow will effectively use the ribs as conduits. By positioning the openings at selected locations, this facilitates introducing the sewage into a specific location within the treatment zone, such as the base of the treatment zone, and ensuring introduction at a desired rate by selecting specific opening sizes. In embodiments where the fluid is introduced directly into the ribs, one or more outlets may be included in the surface of the ribs (forming the outer surface of the modular device) to act as high-level overflows. The opening at the top of the rib can act as a high-level overflow. By including high-level overflows on one or more of the hydraulically connected ribs, the maximum differential head between the inlet water level within the ribs and the purified effluent level within the treatment zone can be obtained, thus ensuring control of the flow rate into the treatment zone. This will ensure that the residence time of the sewage is sufficient for treatment and prevent entrainment of any particulates (such as electro-conductive adsorbent materials) during use.

[0026] The differential head required to drive the sewage through the system is low (although it depends on particle size, particle depth, required flow rate, etc.), typically 1 - 15 cm. Since gravity can provide the necessary driving pressure, this head can generally be used on-site without the need for pumping.

[0027] The ribs may have through - holes that permit fluid flow between the treatment zone and the external space. Such through - holes pass directly through the ribs, extending from the surface in contact with the external space to the surface in contact with the treatment zone. It should be noted that these holes can be offset, with the holes related to the internal treatment zone located at the bottom of the ribs and the holes related to the external space located at a higher position on the vertical portion of the ribs. The advantage of placing these holes at a higher position in the ribs is that the external space can serve as a settling zone, minimizing the entry of solid particles that may be present in the sewage into the bed.

[0028] One or more membranes may be non - conductive. The membranes act as electrical insulators, preventing short - circuits in the circuit during the operation of the modular water treatment device. This also forces electrons to flow out of any conductive adsorbent material within the device and into the water before passing through one or more membranes / separators and then back into any conductive adsorbent material in the adjacent compartment. The flow of electrons in and out of the water can cause the destruction of contaminants through oxidation or reduction (note that polymerization or precipitation may also occur). The destruction may be the result of electrical (direct electrochemical treatment) and / or chemical reactions (indirect electrochemical treatment) that cause the decomposition of the contaminants. For example, these can include direct electron transfer and changes in the pH of the surrounding liquid.

[0029] The modular water treatment device may include at least two electrodes at least partially contained within a container, preferably, where the electrodes are operably connected to a power source. Two electrodes are required to set up the circuit necessary for electrochemically treating the water contained in the container. More electrodes can be used if needed. The electrodes can be connected to a controller. The controller can be configured to selectively adjust the voltage, current, and polarity of the power supply provided to the electrodes. The device can operate unidirectionally, i.e., the current passes in a single direction, or bidirectionally, where the direction of the current is periodically reversed. The current can be reversed to remove any scale or fouling on one or more of the electrodes. The current and / or voltage can be adjusted to ensure that sufficient electrical energy is provided to achieve the desired level of decontamination or water treatment.

[0030] The modular water treatment device may include additional means for delivering air to the treatment zone. Such means may include additional conduits, pipes, and / or bubblers. In embodiments where the ribs are hollow, it may include a connector adapted to connect the air supply means to the internal space of the ribs, and an opening for delivering air to the treatment zone. The opening may be the same as the opening that allows fluid circulation between the external space and the treatment zone. Preferably, air is introduced at the bottom of the treatment zone so that the air passes upward through any specific materials and fluids located in the treatment zone. Surprisingly, during operation of the treatment device, small cavitations may form on the adsorption material. These gases may include hydrogen formed by water decomposition (in the cathode zone), as well as carbon dioxide / monoxide, chlorine, and / or oxygen formed by oxidation of water and organic pollutants in the anode zone. The exact composition of the gas is not particularly important, but the effect is that the contaminated water cannot interact effectively with the adsorption material, and thus any pollutants in the water are not adsorbed on the surface of the adsorption material. Since the destruction of most pollutants occurs on the surface of the adsorption material, if the adsorption of pollutants onto the adsorption material is prevented, the treatment will slow down or stop. In addition, the presence of these bubbles in the system has been found to impede the flow through the bed and reduce the flow rate. Contrary to expectations, surprisingly, adding more gas to the system can remove the bubbles that interfere with the treatment. In addition, it has been found that adding more gas can reduce channelling, where, in the case of channels forming in the adsorption material, the liquid can flow through the channels without passing through the adsorbent material. These channels are disrupted by the passage of large bubbles, and then the bed is remodelled to eliminate any channels that may have formed previously. The reduction or elimination of channels in the adsorption material bed increases the interaction between the adsorption material and the wastewater being treated. In principle, any gas can be provided, but it is most convenient to provide air. The addition of the extra gas can be continuous or intermittent. In practice, it is sufficient to provide the additional gas to the adsorption material bed about two to three times a week for a few minutes (depending on the air or gas flow rate - the higher the air or gas flow rate, the shorter the required time), but this can be done more frequently and / or for different lengths of time as required. The addition of the extra gas can at least partially fluidize the area of the adsorption material bed. The addition of gas is also beneficial for removing fine solids from the system, whether particles that may have entered the wastewater treatment zone or fine particles that may be generated due to the decomposition of any adsorption material used in the system. It should be noted that during the injection of gas into the system, the liquid can continue to flow.

[0031] The modular water treatment device may also include a first end wall and a second end wall. The walls are different from the ribs and may be used to close the other open ends of the container.

[0032] The modular water treatment device may also include a mesh structure configured to prevent solid materials (such as electroconductive adsorption materials) from being lost from the treatment area while allowing fluid flow. The mesh structure may be provided at the bottom of the ribs so that the sewage provided through the openings at the bottom of the ribs can pass through the mesh structure and prevent any electroconductive adsorption material within the device from falling through the openings. Therefore, the mesh structure includes openings sized to prevent the electroconductive adsorption material from passing through. The mesh structure may be provided above the electroconductive adsorption material bed to prevent it from being removed from the system by the treated water flow. Other support systems may also be used alternatively or additionally to prevent the adsorption material from escaping through the openings in the ribs. For example, using gravel and sand of appropriate sizes can achieve this function. This also has the advantage that it helps to diffuse the bubbles from the ribs across the width of the treatment area and prevent the channeling of the bubbles injected through the particle bed. A perforated plate may be used additionally or alternatively to prevent the loss of solid materials.

[0033] A third aspect of the present invention relates to a water treatment system comprising a water tank having an inlet for supplying sewage, one or more modular water treatment devices according to the first aspect of the present invention; the modular water treatment device comprising one or more electrodes; and a power supply operably connected to the electrodes. The modular treatment device may be located in the water tank. In operation, the contaminated water enters the water tank, where it is stored in the water tank before entering one or more treatment areas.

[0034] The water treatment system may also include an electroconductive adsorption material located in at least one of the modular water treatment devices. Any electroconductive adsorption material may be used. The adsorbent may be particulate or sheet-like. These particles provide a large surface area for the pollutants to be adsorbed. In addition, an electric current can pass through the particles, thereby enhancing the effectiveness of the electrochemical treatment by concentrating the pollutants at the locations where the current also passes.

[0035] The electroconductive adsorption material may include intercalated graphite particles or sheets. Such particles or sheets are known to be particularly effective in continuous adsorption regeneration systems. Another advantage is that they do not form toxic by-products during use. NYEX provided by Arvia Technology Limited in the UK TM is an example of such a material, but any electroconductive material capable of adsorption may be used.

[0036] The water treatment system may also include a purified water extractor configured to remove the treated water from the said or each water treatment device. The extractor may include a pump outlet for actively removing the treated water, or a weir for passively removing the treated water when the treated water reaches a set height within the container.

[0037] The water treatment system may include at least two modular treatment devices arranged in parallel. In other words, the modular treatment devices have a common power supply.

[0038] The water treatment system may include at least two modular treatment devices arranged in series. In other words, the output of the first modular treatment device serves as the input of the second modular treatment device, and so on. This allows for staged treatment of different contaminants or contaminant levels that require different treatment conditions, such as current density or residence time.

[0039] The water treatment system may include treatment devices arranged in series and in parallel. For example, four devices may be provided in two groups each including two devices in series, and the two groups are arranged in parallel.

[0040] The or each modular device may have an open top, and at least a portion of the open top is located at a position below the top of the water tank. In these embodiments, overflow of water in the water tank can be provided by allowing water to flow over the top of the container wall. The water level difference can be provided by removing water from the device.

[0041] The water treatment system may further include a gas supply device configured to supply air to the or each treatment zone. As described above, during the electrochemical treatment process, hydrogen (and other) gases are generated, and these gases form a layer of bubbles on the surface of the articles in the container. Contrary to common sense, providing additional gas (usually air) to the treatment zone helps to remove the bubbles. This is particularly advantageous in embodiments using conductive adsorption materials, because the high specific surface area of such materials means that they accumulate hydrogen and other gases, which reduces their contact with water, thereby reducing their effectiveness and causing a reduction in flow rate. This method can also reduce the compaction of the conductive adsorption materials, while simply vibrating the bed layer to remove bubbles will cause compaction of the bed layer, thereby increasing the resistance to the water flow to be treated.

[0042] Air can be supplied to the or each treatment zone through hollow ribs. This reduces or eliminates the need to provide additional air supply equipment. Alternatively, air can be injected outside the module, usually below the module, and the water flow can suck the air into the ribs, where the air is distributed into the bed layer.

[0043] Air can be supplied to the or each treatment zone through a bubbler. A dedicated bubbler can more effectively distribute air to the treatment zone by being separated from the system for supplying water to the treatment zone. A single gas supply device can be configured to selectively supply air to each device as needed. Since it is not necessary to supply additional air to each device simultaneously, a single gas supply device can be used to supply air to each device in the system in sequence.

[0044] The fourth aspect of the present invention relates to a method of constructing a modular water treatment device for a water treatment system, the method comprising the steps of: a) arranging at least two ribs so as to form at least part of a container; b) positioning at least one separator between adjacent ribs; and fixing opposite faces of adjacent ribs to each other and / or fixing opposite faces of adjacent ribs to the separator disposed therebetween. The modular nature of the water treatment device allows for a simple construction method which can be simply adapted to produce a device of any desired size. The fixing may include gluing, solvent cementing or welding, or clamping of the ribs.

[0045] The method may further comprise providing at least two electrodes at least partially within the container. Two electrodes are required to set up the circuit necessary for electrochemically treating the water contained in the container. More electrodes may be used. The electrodes are in electrical communication with a bed of electrically conductive adsorbent material within the device.

[0046] The ribs may include grooves to receive at least one separator, which separator may be a membrane. The grooves may be added to the said or each rib by varying the shape of the rib or by forming the rib into the desired shape (e.g. by extrusion).

[0047] The method may further comprise drilling or otherwise providing holes in the ribs to allow fluid flow. These holes may be through-holes (i.e. passing directly through the rib from one side to the other). If the rib is hollow, the holes may be offset to allow water flow through the rib. The holes may be drilled by any suitable method.

[0048] The fixing may be achieved by adhesives, solvent cements and / or welding. Adhesives and welding are methods which can be used to provide a watertight seal between the ribs and do not interfere with the mating of the ribs as they do not introduce any elements which may lie above the surface of the ribs, such as, unlike a bolt head, which may prevent a tight and / or watertight connection between adjacent ribs. Countersunk fixings (such as screws) may be used as an alternative or additional fixing. The ribs may be clamped together by internal or external members.

[0049] The method may further comprise positioning a bubbler within the container. The bubbler may be used to supply air to the treatment zone to remove hydrogen and prevent any electrically conductive adsorbent material from compacting.

[0050] The fifth aspect of the present invention relates to a method of operating a water treatment device, comprising the steps of: a) injecting sewage into a tank containing a container, the container comprising at least two ribs holding a separator therebetween, the container at least partially containing at least two electrodes; b) conveying the sewage through the container to a treatment zone defined by the container; c) passing the sewage through the treatment zone; d) passing an electric current through the at least two electrodes to convert the sewage within the treatment zone into treated water; and e) removing the treated water from the treatment zone.

[0051] The treatment area can accommodate a conductive adsorbent material. The conductive adsorbent material can include intercalated graphite particles. The conductive adsorbent material can include NYEX provided by Arvia Technology Limited, UK TM or any other conductive material capable of adsorption.

[0052] The method can also include the step of passing air through the conductive adsorbent material at regular intervals. This will remove hydrogen and other gases accumulated during the electrochemical treatment of water from the conductive adsorbent material. This only needs to be done periodically as it takes time for hydrogen and other gases to accumulate on the surface of the conductive adsorbent material.

[0053] The water level in the water tank can be maintained at a level higher than the water level in the container. The water level difference provides a pressure difference that brings water from the water tank into the container. The water level difference can be maintained or adjusted by modifying the rate of water entering the water tank and / or leaving the container. It should be recognized that using this modular approach means that multiple modules can be placed in a larger water tank. The water level in this water tank is maintained by a simple flow rate into the water tank. The water will then flow through the modules and out through the outlet. An adjustable outlet weir can be used to ensure equal flow rates for each device and to maintain equal pressure differences between the modules to keep the flow uniform.

[0054] The container and the electrodes can form part of a modular water treatment device according to the first aspect of the present invention.

[0055] The water tank, the container and the electrodes can form part of a water treatment system according to the third aspect of the present invention. In fact, the features of any aspect of the present invention described herein can be combined with the features of any other aspect of the present invention described herein, unless the features are mutually exclusive. Accordingly, all combinations of the subject matter are expressly contemplated and intended.

[0056] It should be recognized that this construction method provides a very simple way to provide standard and non-standard modules. There is no need for machining and the manufacturing tolerances are low. This minimizes the cost of each module. By keeping the modules small (only a small number of cells in each module provide a low voltage), the operation is simple, the maintenance is simple, and the health and safety issues are minimal. Disconnecting one module will allow it to be removed from the outer tank without stopping the treatment in other modules. Minimal monitoring is required as there can be only one pipe controlling the flow into the outer water tank and only the outlet valve needs to be closed to prevent treatment through the modules. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0058] Figure 1 ribs according to the first aspect of the present invention are shown;

[0059] Figure 2 shows an apparatus including Figure 1 the six ribs, a first end wall, a second end wall, and a separator as shown;

[0060] Figure 3 shows a schematic view of a system including the apparatus and a water tank;

[0061] Figure 4 shows a schematic view of a system including three apparatuses arranged in series;

[0062] Figure 5 shows a schematic view of a system including three apparatuses arranged in parallel;

[0063] Figure 6A shows a cross-section of recessed ribs and a separator before fixation;

[0064] Figure 6B shows a cross-section of recessed ribs and a separator in an assembled state;

[0065] Figure 7 shows a cross-section of optional recessed ribs and a separator;

[0066] Figure 8 is an exemplary schematic view of a cross-section of the system; and

[0067] Figure 9 is a schematic plan view of the system showing an exemplary air supply apparatus. DETAILED DESCRIPTION

[0068] The specific embodiments of the present invention will now be described by way of example only with reference to the drawings briefly described above.

[0069] The modular water treatment apparatus includes a combination of a plurality of ribs and at least one separator (preferably a membrane). The ribs are structural components which are arranged to form a container defining a treatment area, wherein one or more separators are used to divide the treatment area into a plurality of compartments and electrically insulate the electrodes located in the treatment area.

[0070] One embodiment of the rib 100 is as Figure 1As shown. The rib 100 is U-shaped, with the vertical portions 105 being parallel to each other and perpendicular to the base 110. Although depicted as three parts, the vertical portions 105 and the base 110 are preferably formed as a single piece, which can be achieved by providing two 90° elbows in a section of pipe. Of course, any other arrangement of three parts forming a U-shape or a similar shape can be used in this embodiment, provided that when multiple ribs are aligned, they form a container (for example, these parts can form three sides of a trapezoid). Although not described, the pipe can be formed such that it forms a loop, i.e., the pipe loops back on itself to form a closed structure.

[0071] The rib 100 is formed from a plastic square tube, which is hollow and has optional openings 115 at each end. The rib 100 can be extruded with the angle formed after the vertical portion 105 and the base 110, or the angle can be formed during the extrusion process. In the case of being manufactured in different cross-sections, the joints can be at a 45° angle, which will allow the hollow interior to run through the rib, but it should be understood that other angles are also applicable. Hydraulic connection can also be achieved by other means.

[0072] Depending on the size of the container (and treatment area) required for its intended application, the rib 100 can be formed in any suitable size. The rib preferably has sufficient stiffness and does not require any additional support or backing, although support or backing can be provided if needed.

[0073] The rib 100 has a series of holes 120. There are inlet holes 120a on the sides of the vertical portion 105 (which will form the outer surface of the container), and holes 120b facing the treatment area on the upper surface of the base 110. This arrangement of the holes 120 allows water to flow into the container through the internal space of the rib 100, and the water flow is driven by maintaining a higher water level outside the container than inside. The flow rate can be controlled by designing the holes during construction (i.e., larger holes allow higher flow rates) and by monitoring and controlling the relative water levels inside and outside the container. In some embodiments, the holes 120a are not provided, and the liquid to be treated is provided through the openings 115 or other appropriately positioned openings. In this embodiment, an external storage tank is not required because the hollow rib provides a channel for liquid flow and distribution. In one embodiment, there can be additional holes on the outside of the base 110, allowing liquid to flow directly through the holes 120b from the outside of the tank.

[0074] In certain embodiments not described, the opening 115 may be provided with a cap and / or a connection for air and / or liquid supply. Once assembled into a container, supplying compressed air through the opening 115 to the internal space of the rib 100 will cause the air to leave the rib 100 through the holes 120b facing the treatment area. This air will agitate any conductive adsorbent material, thereby removing any hydrogen adsorbed on the surface of the material. In another embodiment, air may be introduced below the rib 100, where additional holes allow the air to enter the rib 100 through the holes. Then, the air escapes through the holes 120b in the rib 100 and passes upward through the bed.

[0075] As Figure 2 shown, the ribs 100 are assembled into a modular water treatment device 200. For clarity, Figure 2 the holes 120 and the opening 115 are omitted. A series of six ribs 100 have been arranged to form a container 205. Although six ribs 100 are used in this example, it should be understood that essentially any number of ribs 100 can be used to obtain a container 205 of the desired length. Adjacent ribs 100 may be fixed to each other by an adhesive, but any other suitable fixing method (such as welding) may be used. A gasket may be provided between the ribs. The gasket may be a film or a barrier material.

[0076] End walls 210 have been provided to enclose the treatment area defined by the container 205. The end walls 210 are made of plastic and are connected by the same fixing method used for the walls, although any suitable connection method may also be used. The plastic end walls ensure that the overall container 205 is electrically insulated. Of course, any other suitable material may be used. This allows multiple devices 200 to be used in close proximity in a single box without interference. In an alternative embodiment, the end walls 210 may be partially or entirely composed of a conductive material (such as metal, carbon) and used as electrodes. This design may also be used in cases where two (or more) modules can be connected together by conductive end plates that act as electrodes between the modules.

[0077] A separator 215 is located between the third and fourth ribs 100, dividing the treatment area into two compartments. The edges of the membrane 215 are clamped between the surfaces of the third and fourth ribs 100, thereby being fixed in place. Similarly, it can be understood that there may be multiple separators in the device.

[0078] Once assembled into a water treatment system, the compartments will contain a conductive adsorbent material and an appropriate number of electrodes or current feeders. The membrane 215 prevents short-circuiting through the adsorbent material while allowing conduction through ion movement. The conductive adsorbent material acts as a bipolar electrode in a multi-cell module, with each cell being defined by two membranes and the rib located between the membranes, except for the terminal cells, which are defined by one membrane, an end wall, and the rib located between the membrane and the end wall.

[0079] Figure 3 Shows a schematic view of a water treatment system 300 including a water tank 305 and a modular water treatment device 200. The water tank 305 includes an inlet 310, and the modular water treatment device 200 is positioned within the water tank 305 by a purified water extractor 315. For clarity, electrodes and power supplies are omitted in this schematic view.

[0080] In use, sewage 320 is supplied to the water tank 305, and the water tank 305 is filled to a first liquid level 325. Water preferably flows into the device 200 through holes 120 in the ribs and is electrochemically treated in the treatment area by applying an electric current to the electrodes, and organic pollutants are destroyed by known processes. The treated water accumulates in the container 200 until a second liquid level 330 is reached, at which point the treated water is removed from the container 200 through the purified water extractor 315. The extractor 315 can be of any suitable form, for example, a horizontal or vertical tube with a float valve, the wall of which forms a weir. It should be understood that the water extractor can also be referred to as an outlet.

[0081] The flow rate of water flowing into the container through the holes is controlled by the relative heights of the first liquid level 325 and the second liquid level 330. To some extent, this is preset by the physical layout of the inlet 310 and the extractor 315, but the flow rate can still be modified by controlling the polluted water flow 320 to adjust the first liquid level 325. Therefore, the system 300 can be provided with sensors, flow control devices, and / or controllers.

[0082] In this embodiment, the open top of the device 200 is located below the top of the water tank 305. In normal use, the first liquid level 325 of the water in the water tank is located below the top of the device 200, so water must enter the device 200 at a controlled rate through the holes. However, in the special case where the amount of water entering the water tank 305 greatly exceeds the amount of water leaving the water tank 305, the first liquid level 325 will rise, and there is a risk that the location where the water treatment system 300 is located will be flooded. This embodiment prevents this situation because the device 200 serves as an overflow mitigation. When the height of the first liquid level 325 exceeds the height of the device 200, the excess water flows into the device 200 through the top. This prevents the first liquid level 325 from rising further and prevents the water in the water tank 300 from escaping.

[0083] Figure 4A schematic view of a water treatment system 400 is shown, in which three devices 200 are arranged in series, with each device 200 located in a separation tank 305 (it should be understood that there can be multiple devices 200 in each separation tank). The extractor 315a of the first device 200a forms the feed to the water tank 305b in which the second device 200b is located, and the extractor 315b of the second device 200b forms the feed to the water tank 305c in which the third device 200c is located. Any number of water tanks 305 and devices 200 can be used according to system requirements. The treatment of water by successive devices 200 is very effective in removing contaminants because the water must pass through multiple devices 200.

[0084] By the relative heights of the inputs and extractions through each water tank 305 and device 200, flow is maintained in a Figure 4 series of devices to maintain the pressure differential across the walls of each device 200. In other words, for each subsequent device, the extractor is located at a lower height, allowing the water to flow under gravity. In an alternative embodiment, the flow is maintained by a pump, which requires additional power and equipment but eliminates the physical limitations required by the system.

[0085] Figure 5 A schematic view of a water treatment system 500 is shown, in which three devices 200 are arranged in parallel. There is a single inlet 310 that supplies contaminated water to a common water tank 305 in which all three devices 200 are located. The treated water from the devices 200 is collected by a common extraction system 505. The water treatment performed by multiple devices 200 operating in parallel allows for the rapid treatment of large volumes of water.

[0086] Figure 6A A cross-section of the rib and the membrane before fixation is shown. Each rib 600 includes a recess 605 for fixing the membrane 610. The depth and width of each recess 605 are sufficient to accommodate the width of the membrane 610 while ensuring a large enough contact area between the membrane 610 and the rib 600 to securely fix the membrane 610 during the assembly of the membrane 610.

[0087] Figure 6B A cross-section of the rib and the separator in the assembled state is shown. Adjacent ribs 600 are fixed to each other, and the membrane 610 is firmly held in the recess 605 of the second rib so as to be in frictional engagement with the second and third ribs. In certain embodiments, adhesives, solvent cements, and / or welding can also be used to fix the membrane 610 to the recess 605.

[0088] The recess 605 can be formed during the extrusion of the rib 600. Alternatively, the recess 605 can be added to the rib 600 by changing the rib shape. This can be achieved by any suitable method, such as laying grooves or deforming the shape of a hollow rib, or adding a piece of plastic to a square tube. During assembly, there may be a protrusion adjacent to the recess that extends into the recess to more firmly secure the membrane in place.

[0089] Figure 7 A cross-section of an optional ribbed and separator is shown. In this embodiment, each rib 700 includes a plurality of recesses 705 configured to accommodate a portion of the width of the membrane 710 when the rib 700 is in an assembled state. In other words, adjacent recesses 705 of adjacent ribs 700 form a space sufficient to accommodate the membrane 710.

[0090] Figure 8 Is an exemplary schematic diagram of a system cross-section, in which the water flow through the system is shown. In this example, the system 800 includes a water tank 805 that houses a water treatment device 810. Contaminated water enters the water tank 805 as a water flow 820 through an inlet 815. The contaminated water flows from the water tank 805 through a hole 825 into the internal space of the ribs of the device 810 and then through a hole 830 into the treatment area of the device. Then, the contaminated water flows through an adsorption material bed 835, and when the water flows, an electric current flows through the adsorption bed through electrodes (not shown) to electrochemically treat the water by electrochemically destroying the contaminants therein. The treated water accumulates above the adsorption material 835 and is discharged through a purified water extractor 840. By maintaining the water level in the water tank 805 higher than the water level in the device 810, the head pressure that guides the water flow is ensured to ensure that the water flows through the internal space of the ribs and the adsorption bed. Loss of the adsorption material is prevented by using a mesh structure 845 below the adsorption material 835 (to prevent the material 835 from falling into the ribs of the device 805 through the hole 830) and a mesh structure 850 above the material 835 (to prevent the material from being entrained in the water flow and flowing out through the purified water extractor 840).

[0091] Figure 9It is a schematic plan view of the system, showing an exemplary air supply device. System 900 includes a water tank 905, which contains six devices 910 including a plurality of ribs 915 (of course, any number of devices can be used). For clarity, membranes, sewage inlets, holes, and purified water extractors are omitted in the figure. Each rib 915 is connected to the air supply device 915 through a pipe 920. Of course, not necessarily every rib 915 is connected to the air supply device, and only enough ribs 915 are needed to ensure sufficient air supply to effectively remove adsorbed hydrogen or other gases in the adsorption material. The air supply device 915 supplies air to the ribs 915, and the internal space of the ribs acts as a conduit to guide the air to the bottom of the conductive adsorption material. Then, the air continues to flow through the material, agitating the material and removing hydrogen and other gases adsorbed on the surface of the material. Alternatively, the pipe 920 can bypass the ribs and directly enter the device 910; in these embodiments, a bubbler can be connected to the pipe to ensure effective air supply to the material. Alternatively, air can be introduced under the ribs, allowing it to flow through the ribs and into the bed.

[0092] The electrochemical process produces hydrogen at a gradual rate. Therefore, it is only necessary to periodically remove the trapped hydrogen or other gases (e.g., by passing air through the material), and most of the gases escape through the bed by coalescing into larger bubbles. Therefore, the air supply device 915 can provide air only when needed. In addition, the pipe 920 and / or the air supply device 915 can be provided with a plurality of valves and / or a controller configured to guide air to the device 910 in a sequential manner.

[0093] The present invention provides a highly flexible and configurable system that can be used for sewage treatment. The system is modular because it is composed of ribs, allowing the size of the device to be changed by varying the number of ribs used to form the device. The ribs are preferably hollow to allow the structure of the device to also serve as a flow conduit. In addition, since the ribs can sandwich the separator between them, it is easier to ensure the watertight seal between different compartments in the device, while it is difficult and time-consuming to insert the separator and ensure its non-leakage when a single water tank is required to be divided into multiple separate compartments. Since the separator is very thin, usually about a few millimeters or less, it is difficult to provide a good seal by connecting the separator to the inner wall of a conventional water tank. In contrast, the present invention allows the separator to be restricted between adjacent ribs, thus ensuring a quick and reliable seal and holding the separator in the device more safely and firmly than previously achieved.

Claims

1. A modular water treatment device for an electrochemical water treatment system, comprising: Two or more ribs arranged to form a base and multiple walls of a container, the container having an open top, each rib being elongated and having at least one curve or bend along its length, the two or more ribs being arranged face to face to define a treatment area within the at least one curve or bend, the ribs being configured to engage with adjacent ribs to form a fluid seal; One or more separators arranged between opposite faces of adjacent ribs such that the one or more separators are clamped between the adjacent ribs, thereby dividing the treatment area into multiple compartments, wherein the separator or each separator is a membrane; And A first end wall and a second end wall for closing the ports of the container.

2. The modular water treatment device according to claim 1, wherein: i. The ribs are hollow; and / or ii. The ribs are substantially U-shaped.

3. The modular water treatment device according to claim 1, wherein: i. The ribs comprise plastic; and / or ii. The ribs comprise a recess for receiving the one or more separators.

4. The modular water treatment device according to any one of claims 1 to 3, wherein the ribs are configured to allow fluid to flow through the internal space of the ribs into the treatment area.

5. The modular water treatment device according to claim 4, wherein the ribs have multiple through-holes allowing fluid to flow into the treatment area.

6. The modular water treatment device according to any one of claims 1 to 3, further comprising: i. A mesh structure configured to prevent solid materials from leaving the treatment area of the container; And / or ii. Means for delivering air to the treatment area.

7. The modular water treatment device according to any one of claims 1 to 3, wherein each separator is non-conductive.

8. The modular water treatment device according to any one of claims 1 to 3, wherein the modular water treatment device comprises at least two electrodes at least partially contained within the container.

9. The modular water treatment device according to any one of claims 1 to 3, wherein the device comprises a conductive adsorption material within the treatment area.

10. An electrochemical water treatment system, comprising: A water tank having an inlet for supplying sewage; One or more modular water treatment devices as defined in any one of claims 1 to 9, located within the water tank; The modular water treatment device comprising one or more electrodes; And A power supply operably connected to the electrodes.

11. The water treatment system according to claim 10, further comprising: i. A conductive adsorption material located in at least one of the modular water treatment devices; And / or ii. A purified water extractor for removing treated water from or each water treatment device.

12. The water treatment system according to claim 10 comprises: i. At least two modular treatment devices arranged in parallel; And / or ii. At least two modular treatment devices arranged in series.

13. The water treatment system according to any one of claims 10 to 12, wherein at least a part of the top of the container is located at a position lower than the top of the water tank.

14. The water treatment system according to any one of claims 10 to 12, further comprising a gas supply device configured to supply air to the treatment zone or each treatment zone.

15. A method of constructing a modular water treatment device for an electrochemical water treatment system, the method comprising the steps of: a) arranging at least two ribs to form a base and a plurality of walls of a container, the container having an open top, each rib being elongated and having at least one curve or bend along its length, the two or more ribs being arranged face to face to define a treatment zone within the at least one curve or bend, the ribs being configured to engage with adjacent ribs to form a fluid seal; b) positioning at least one separator between opposite faces of adjacent ribs such that the one or more separators are clamped between the adjacent ribs, whereby the treatment zone is divided into a plurality of compartments, wherein the separator or each separator is a membrane; and c) fixing the opposite faces of adjacent ribs to each other and / or fixing the opposite faces of adjacent ribs to the separator disposed therebetween.

16. The method according to claim 15, further comprising: i. providing at least two electrodes at least partially within the container; and / or ii. drilling holes in the ribs to allow fluid flow; and / or iii. placing a bubbler within the container.

17. The method according to claim 15 or 16, wherein the rib comprises a groove to accommodate the at least one separator.

18. The method according to any one of claims 15 to 16, wherein the fixing is achieved by adhesive, solvent cement and / or welding.

19. A method of operating a modular water treatment device, comprising the steps of: a) injecting sewage into the electrochemical water treatment system according to any one of claims 10 - 14, the container at least partially accommodating at least two electrodes; b) conveying the sewage through the container to the treatment zone defined by the container; c) passing the sewage through the treatment zone; d) passing an electric current through the at least two electrodes to convert the sewage within the treatment zone into treated water; and e) removing the treated water from the treatment zone.

20. The method according to claim 19, wherein the treatment zone accommodates a conductive adsorbent material.

21. The method according to claim 20, further comprising the step of passing air through the conductive adsorbent material at regular intervals.

22. The method according to any one of claims 19 to 21, wherein the water level in the water tank is maintained at a level higher than the water level in the container.

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