TWI519487B - A water purification device - Google Patents

Description

Water purification device

The present invention relates to a water purification apparatus and a method for water purification, and in particular to a water purification apparatus that can be used as a gravity feed system or suitably connected to a main water supply system.

The present invention has been primarily developed for use in potable water applications and will be described below with reference to this application. However, it is to be understood that the invention is not limited to this particular field of use.

Any discussion of prior art throughout the specification should not be taken as an admission that this prior art is broadly known or constitute a part of common general knowledge in the field.

There are a large number of people in the world living in countries with severe drinking water shortages. People have to rely directly on groundwater sources (such as wells), ponds and rivers. Such water sources are often contaminated by sewage, industrial effluents and agricultural by-products such as pesticide residues. To make water safe for microorganisms, WHO recommends removing 6 log bacteria, removing 4 log viruses, and removing 3 log cells. Although bacteria and viruses can be removed to the required range by using chemical disinfection (for example, by contact with halogen) or radiation-based disinfection (for example, by exposure to ultraviolet radiation), such sterilization methods cannot achieve 3 log The cyst is removed.

Gravity feed devices can be obtained that can be combined with a biocide to achieve 6 log bacterial removal, 4 log virus removal, and 3 log cyst removal. The gravity feed device operates in the absence of pressurized and flowing water.

WO 2005095284 (Unilever, 2005) discloses a gravity feed water purification system comprising a filtration unit suitable for separating particulate soluble material from input water, and the unit is in the form of a carbon block and generally has an additional non-woven filter; a chemical dispensing unit such that the flow rate of water exiting the filtration unit is controlled by the flow control member before the water encounters the biocide dispensed by the chemical delivery unit, after which the water is retained in the detention chamber for a predetermined period of time and then adapted for delivery The biocide and its by-products leave the water purification system from the deionized water separation purifier member. This device is very complex and has a large number of replaceable parts.

WO 07000238 (Unilever, 2007) discloses a water purification apparatus comprising an upper chamber and a lower chamber, the chambers comprising an outlet member for collecting purified water and a filter medium for removing suspended particles and dissolving organic matter. The biocide system integrated therewith can dispense a unit dose of biocide and can feed water to a device in which the biocide can be dispensed. This is only for solid biocides and is not suitable for liquid biocides.

WO 08083896 (Unilever, 2008) discloses a gravity feed water purification apparatus that can be incorporated into a controlled administration of a liquid biocide. The device uses a delivery channel comprising a venturi, wherein a top chamber is in fluid communication with a bottom chamber and water can flow from the top chamber to the bottom chamber. The water in this system needs to flow at a high flow rate and the rate of administration depends on the flow rate of the water. The biocide is caused by a negative (inhalation) pressure at the discharge end of the liquid delivery tube, the negative pressure being passed through a venturi that is gas-tightly connected to the discharge end of the tube. Caused by. The gas pressure in the compartment containing the liquid biocide is atmospheric in this case, which is "sucked" from the compartment containing the biocide due to the negative pressure at the discharge end. In fact, venturi-based delivery systems are highly sensitive to physical dimensions and dose control is more difficult. This system requires a large amount of construction material and thus becomes expensive.

EP 2184263 (Unilever) discloses a weight feed water purification apparatus in which the concentration of the biocide or its by-products in the downstream water is reduced by the combination of the outlet setting characteristics and the height of the separation reservoir and the wall of the purifier unit. A relatively long purification medium life is obtained. The device includes a biocide biocide unit in fluid communication with the reservoir, the reservoir being separated from the purifier unit having the purification medium by a wall, and the purifier unit is present by An outlet on the separator separating the purifier unit from the dispensing chamber is in fluid communication with the dispensing chamber. To achieve this, at least 10% by weight of the medium (M) needs to be below the lowest reference plane of the outlet (O), and the wall (W) extends above the highest reference plane of the medium and is higher than the lowest of the outlet. Datum. This document does not disclose or discuss how to administer biocides, and does not disclose a liquid biocide delivery system.

The present inventors have devised a liquid biocide administration system and a configuration for delaying the contact of the water having been dispensed with the biocide with the filter-biocide purification member and adapting it to the gravity feed water purification device.

WO 04074182 A (Unilever) discloses a flow control member for controlling the leaching of a solid biocide by controlling the flow of water into a solid biocide dispensing unit. This document discloses a flow control member that provides a constant flow through the chemical dispensing unit to leach a uniform amount of solid biocide without being affected by the input head in the top chamber. The biocide is applied to the water to gradually erode the solid biocidal tablet by contact with water, and the flow of water is controlled by a flow regulator, which sequentially controls the erosion of the biocidal tablet. It does not reveal how to control the administration of liquid biocides.

US 4093551 (IFUO AB) discloses a device for purifying water in a small sewage system comprising a component that automatically adds a chemically active liquid to water passing through the device. The present invention eliminates the need for any movable parts by using two siphons that control the supply of liquid. One of the siphons passes through the sewage and the corresponding flow produces a suction that transfers the chemically active liquid through the second siphon. This document discloses a liquid disinfectant delivery system in which the liquid system is administered by "suction" or negative pressure formed in a siphon when water flows. The discharge end of the second siphon immersed in the liquid biocide tank at one end is placed in the first siphon. Thus, as the water flows through the first siphon, the liquid biocide is "sucked" into the siphon. Therefore, the two siphons used form the liquid delivery system.

The inventors have designed two siphons to provide a means for delaying the introduction of water with biocide added to the biocide purification section and such siphons do not control the dosage of liquid biocide. The two siphons are not physically connected, but only provide a residence time for the biocide to act on the microorganisms, while the liquid disinfectant dose is caused by the positive pressure established by the bladder.

Accordingly, the inventors have devised a novel liquid administration device that is controlled by the positive pressure established by the hydrostatic pressure difference of the water and that is provided by two siphons arranged in a clear manner that provides additional residence time. The interaction of the biocide with the water to be purified.

A water purification apparatus is described in the Indian Patent Application No. 2126/MUM/2009, the entire disclosure of which is incorporated herein by reference in its entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire all One of the necessary features of this device is to fill the cup which, when filled, allows the administration system to administer the desired amount of biocide in the water purification chamber. The device cannot function properly without the filling cup. The disadvantage of the presence of a filled cup is that it is difficult to miniaturize the device.

The inventors have been able to design a novel biocide delivery system by using a pressure transfer tube in conjunction with a siphon discharge mechanism. The relative position of the siphon discharge mechanism to the pressure transfer tube allows the purification device to function properly. In addition, the geometry of the tube, along with its immersion length, controls the biocide administration. The device of the present invention is designed to be free of the filled cup, thereby making it easier to miniaturize.

In light of the above discussion, it is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art.

It is an object of the present invention to provide a water purification apparatus that is less complex and thereby economical to construct.

Another object of the present invention is to provide a water purification apparatus which is simultaneously suitable for use with solid and liquid biocides.

Another object of the present invention is to provide a water purification apparatus that can be used as a gravity feed device and that is suitable for use in an in-line system.

A further object of the invention is to provide a residence time member within the water purification unit to ensure that even the first drop of water from the water purification unit is completely free of any harmful microorganisms.

According to one aspect of the present invention, there is provided a water purification apparatus comprising a water purification chamber, comprising: a biocide dispensing cartridge in fluid communication with a biocide storage compartment and a biocide dispensing port, wherein the biocide dispensing a cassette is coupled to the pressure transfer tube and the free end of the tube extends downwardly into the water purification chamber; the water purification chamber is flowed into the siphon discharge mechanism and the filter chamber fluid via an inverted "U" shape having unequal length feet Connecting; wherein the opening of the short leg of the inflow siphon discharge mechanism is located above the bottom of the water purification chamber; the long leg extends into the filter cavity and the inverted U-shaped inflow into the siphon discharge mechanism is located at the top of the tube Above the end.

According to another preferred aspect of the present invention, there is provided a water purification apparatus according to the present invention, wherein the inflow siphon discharge mechanism is in fluid communication with the filter chamber via a residence time chamber and in fluid communication with an outflow siphon discharge mechanism, wherein The outflow siphon discharge mechanism is sealed in the residence time cavity.

The term "comprising" is used to mean that it is not limited to any of the elements that are subsequently recited, but is intended to cover unrepresented elements having a primary or secondary functional importance. In other words, the steps, components or options listed are not necessarily exclusive. When the terms "comprising" or "having" are used, such terms are intended to be equivalent to "including" as defined above.

Accordingly, the present invention provides a water purification apparatus comprising a water purification chamber, comprising: a biocide dispensing cartridge in fluid communication with a biocide storage compartment and a biocide dispensing port, wherein the biocide dispensing cartridge is coupled to a pressure transfer tube having a free end extending downwardly into the water purification chamber; the water purification chamber being in fluid communication with the filter chamber via an inverted "U" shaped inflow siphon discharge mechanism having unequal length legs; The short foot opening into the siphon discharge mechanism is located above the bottom of the water purification chamber; the long leg extends into the filter chamber and the top of the inverted U-shaped inflow siphon discharge mechanism is above the free end of the tube.

The tubes can have different shapes and sizes and can have different cross sections. The tube cross section can be rectangular, circular, polygonal, elliptical or a different other geometric shape. The tube can be fully or partially tapered in any direction.

The apparatus of the present invention can be made to different capacities and sizes, such as 1, 2, 3, 5 liters or more.

The biocide can be provided in solid or liquid form. When in solid form, the device is designed to dissolve a suitable amount of solids to provide the correct amount of liquid biocide in the biocide dispensing cartridge. Preferably, the biocide is selected from any halogen-releasing compound and preferably a chlorine-releasing biocide comprising chlorinated trisodium phosphate, sodium or potassium hypochlorite or calcium, various N-chlorinations known in the art to release active chlorine. a compound such as sodium or potassium dichloroisocyanurate, trichlorocyanuric acid, monochloramine, dichloramine, [(monotrichloro)-tetrakis(monopotassium dichloride)] penta-isocyanurate, 1,3- Dimethyl-5,5- dimethylidanotone, chloramine T, p-toluene-sulfochloramide, trichloromelamine, N-chloramine, N-chlorosuccinimide, N, N '-Dichloro azo dimethyl hydrazine, N-chloroethyl hydrazino-urea, N,N-dichloro azo dimethyl hydrazine, N-chloroethyl hydrazino urea, N,N-dichloroform urea N, N-dichlorbiurile, dicyandiamide, hydrogen peroxide or its derivatives, peracetic acid.

Suitable liquid biocides useful in the devices of the present invention include sodium hypochlorite, sodium dichloroisocyanurate, iodine, quaternary ammonium compounds or aqueous solutions of glutaraldehyde. The most preferred liquid biocide is an aqueous solution of sodium hypochlorite. When the liquid biocide used is sodium hypochlorite, it is added to the water in a concentration of from 0.01 to 50% by weight, more preferably from 1 to 20% by weight, in the biocide storage compartment. By using the apparatus of the present invention, a concentration of 0.5 to 100 ppm by weight, more preferably 1 to 50 ppm by weight, of the biocide in water can be obtained in the water purification chamber.

According to a preferred aspect of the invention, the filter can be combined with a biocide purifier. The filter-biocide purifier preferably comprises an activated carbon block filter medium. The activated carbon block filter medium comprises powder activated carbon (PAC) and a binder which are thoroughly mixed and formed into a compact by pressure and heat treatment. Preferably, the PAC is selected from the group consisting of bituminous coal, coconut shell/charcoal, and petroleum sputum. Preferably, the PAC used has a size uniformity factor of less than 2, or more preferably less than 1.5, more than 50%, more preferably more than 60% of the number of carbon tetrachloride.

The filter-biocide purifier further has a particulate filter which is a single or multi-layer nonwoven fabric filter in which the outermost layer is folded. Alternatively, the filter may comprise a combination of folded and spirally wound fabric filters.

Particularly preferred carbon block filter media are disclosed in GB 2390987, and more preferably in their application in the application 320/MUM/2004. The application in the same application describes a carbon block filter medium for use in a gravity feed filter comprising powder activated carbon having a particle size of 95 mesh by passing 95 mesh and not exceeding 12% by 200 mesh. (PAC) and a binder having a melt flow rate (MFR) of less than 5. More preferred carbon block filter media have from 55 to 80% by weight of PAC particles in the lower 50% by volume of the carbon block filter media in the 100 to 200 mesh size range.

The discharge mechanism can be a faucet or a wind actuated hand pump as discussed below.

The invention will now be illustrated by way of specific non-limiting examples of the water purification apparatus of the invention of Figures 1 to 3.

The drawings are discussed in detail:

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is an illustration of one embodiment of the water purification apparatus of the present invention. The device has a water purification chamber (1) provided with a cover (6) which is opened to expose the inlet, thereby allowing the user to pour water into the water purification chamber. The water purification chamber contains a biocide dispensing cartridge (3) in fluid communication with the biocide storage compartment (5) and the biocide dispensing port (4). The biocide dispensing cartridge is coupled to a pressure transfer tube (2) that extends down into the water purification chamber. The tubing is in fluid communication with the biocide dispensing cartridge. The water purification chamber is in fluid communication with a filter chamber (10) having a filter-biocide purifier (7) via an inverted U-shaped inflow siphon discharge mechanism (13). The short foot opening into the siphon discharge mechanism is located above the bottom of the water purification chamber. The filter is located on a dividing wall separating the water purification chamber from the pure water discharge chamber. The inflow siphon discharge mechanism is provided to operatively connect the water purification chamber to the filtration chamber such that water flows from the water purification chamber into the filtration chamber only via the inflow siphon discharge mechanism. The venting opening (12) provided at the filter chamber allows the inflow siphon discharge mechanism to be operated by directing the passage away from the filter chamber. The water system exits the filtration chamber via the filter-biocide purifier while water enters the filtration chamber via the inflow siphon discharge mechanism. The top of the inverted U-shaped inflow siphon discharge mechanism is located above the free end of the tube to ensure that no water is passed through the siphon discharge mechanism if the required amount of biocide is not added. A watertight cover (11) provided at the filter chamber ensures that water enters the filter chamber only via the inflow siphon discharge mechanism. When the water purification chamber (1) is filled to the top of the inflow siphon discharge mechanism, the inflow siphon discharge mechanism begins to discharge water into the filter chamber. When the biocide-containing water fills the filter chamber, water flows through the filter-biocide purifier to remove the colloidal impurities and residual biocide from the water and discharge the water to the pure water discharge chamber ( In 8), pure water without biocide can be obtained from a pure water discharge chamber via a dispensing member such as a faucet (9).

When water flows into the water purification chamber through the inlet of the water purification chamber and fills it up, the water level in the water purification chamber establishes a pressure in the tube and the biocide suicide bioreagent delivery box is dispensed via the biocide The mouth is discharged into the water purification chamber.

Figure 2 is another embodiment of the water purification apparatus of the present invention having a residence time providing member. Figure 2 shows a water purification chamber (1) providing a filter chamber (10) sealing the filter-biocide purifier (7) at its bottom inner section. The filter chamber is provided with a watertight cover (11) and a venting opening (12). The biocide dispensing cartridge (3), the biocide dispensing opening (4), the biocide storage compartment (5), and the tube (2) are in their respective positions as shown in FIG. In Figure 2, a residence time chamber (14) is provided with an outflow siphon discharge mechanism (15). The outflow siphon discharge mechanism is sealed in the residence time cavity. The residence time chamber has a venting opening (16). The venting opening provided at the residence time chamber permits operation of the outflow siphon discharge mechanism by directing the passageway away from the residence time chamber. The inflow siphon discharge mechanism (13) is operatively coupled to the residence time chamber. The inflow siphon discharge mechanism is in fluid communication with the filter chamber via the residence time chamber and in fluid communication with the outflow siphon discharge mechanism. The apparatus of Figure 2 is designed to double the residence time, which ensures that even the first drop of water flowing from the pure water discharge chamber is free of any harmful microorganisms.

In use, the water purification chamber is filled to establish a gas pressure in the tube which is subsequently delivered in the biocide dispensing cartridge, resulting in administration of the biocide via the biocide dispensing port. After the water level in the water purification chamber reaches the highest reference surface flowing into the siphon discharge mechanism, the water mixed with the biocide enters the residence time chamber via the inflow siphon discharge mechanism. After entering the residence time chamber, water begins to fill the residence time chamber. When the water level in the residence time chamber reaches the highest reference surface of the outflow siphon discharge mechanism, water mixed with the biocide enters the filter chamber via the outflow siphon discharge mechanism, thereby providing double residence time. After removing the residual biocide and filtering it in the filter chamber, the pure water can be discharged from the pure water discharge chamber by opening the faucet.

Figure 3 is another embodiment of the water purification apparatus of the present invention. All of the features and characteristics of Figure 3 are the same as those described in Figure 1. The only difference between the embodiment of Fig. 1 and Fig. 3 is that in Fig. 3, the biocide storage compartment (5), the biocide delivery box (3), and the biocide dispensing port (4) are sealed. The water is purified inside the chamber.

Example: The geometry of the tube and the height of the immersion tube for the action of liquid biocide:

In this example, the immersion tube height means the length of the tube soaked in the water of the water purification chamber, that is, the distance between the highest water level in the water purification chamber and the lowest point of the pressure transfer tube. In Table 1, L1 and L2 mean two different sides of a rectangle and a square.

Table 1 below shows the effect of the geometry of the tube and the height of the immersion tube on the biocide administration.

It is apparent from the data in Figure 1 that the biocide dosage will vary by changing the geometry of the tube and the height of the immersion tube. Therefore, the volume of the biocide administered can be accurately controlled according to the capacity of the water purification device.

The residence time cavity is used to increase the contact time between the biocide and the unpurified (input) water:

Using the device constructed as shown in Figures 1 to 3, the time taken for the water containing the biocide dispensed by the suicide bioreagent delivery cartridge to pass through the filter is referred to as the contact time. This contact time will be the duration of time during which the biocide acts on the microorganisms entering the water.

Table 2 summarizes the contact time for the presence and absence of this residence time cavity.

As can be seen from the data in Table 2, the contact time can be increased by providing a residence time chamber as shown in the preferred embodiment of FIG. This feature has been found to ensure that even the first drop of water from the water purification device of the present invention is free of any harmful microorganisms.

1. . . Water purification chamber

2. . . Pressure transfer tube

3. . . Biocide distribution box

4. . . Biocide distribution port

5. . . Biocide storage compartment

6. . . Cover

7. . . Filter - Bio-purifier

8. . . Pure water discharge chamber

9. . . Faucet

10. . . Filter chamber

11. . . Watertight cover

12. . . Vent

13. . . Inverted U-shaped siphon discharge mechanism

14. . . Residence time cavity

15. . . Outflow siphon discharge mechanism

16. . . Vent

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is an illustration of one embodiment of the water purification apparatus of the present invention.

Figure 2 is a more preferred embodiment of the water purification apparatus of the present invention having a residence time providing member.

Figure 3 is another embodiment of the water purification apparatus of the present invention in which the biocide dispensing unit is sealed within a water purification chamber.

1. . . Water purification chamber

2. . . Pressure transfer tube

3. . . Biocide distribution box

4. . . Biocide distribution port

5. . . Biocide storage compartment

6. . . Cover

7. . . Filter - Bio-purifier

8. . . Pure water discharge chamber

9. . . Faucet

10. . . Filter chamber

11. . . Watertight cover

12. . . Vent

13. . . Inverted U-shaped siphon discharge mechanism

Claims (9)

A water purification device comprising a water purification chamber (1), comprising: a biocide distribution box comprising a biocide and a biocide. a storage compartment (5) and a biocide distribution port (4) In fluid communication, wherein the biocide dispensing cartridge (3) is coupled to a pressure transfer tube (2) and the free end of the tube extends downwardly into the water purification chamber (1); the water purification chamber (1) is via An inverted U-shaped inflow into the siphon discharge mechanism (13) having unequal length legs is in fluid communication with the filter chamber (10); wherein the opening of the short leg of the inflow siphon discharge mechanism is at the bottom of the water purification chamber (1) Above; the long leg extends into the filter chamber (10) and the top of the inverted U-shaped inflow siphon discharge mechanism (13) is above the free end of the tube, wherein during operation, the water purification chamber is The water level establishes a gas pressure in the tube and discharges the biocide from the biocide dispensing cartridge to the water purification chamber via the biocide dispensing port. The water purification apparatus of claim 1, wherein the inflow siphon discharge mechanism is in fluid communication with the filtration chamber via a residence time chamber (14) and in fluid communication with an outflow siphon discharge mechanism (15), wherein the outflow siphon discharge mechanism is sealed In the residence time of the residence time. A water purification apparatus according to claim 2, wherein a venting opening (16) is provided at the residence time chamber. The water purification apparatus of any one of claims 1 to 3, wherein the water purification chamber has an inlet adapted to receive input water in the water purification chamber. The water purification device according to any one of claims 1 to 3, wherein the biocide dispensed from the biocide dispensing cartridge is in a liquid form. A water purification apparatus according to any one of claims 1 to 3, wherein a filter (7) is sealed in a filter chamber containing a venting opening (12). The water purification device of claim 6, wherein the filter comprises an activated carbon block filter medium. A water purification apparatus according to claim 6, wherein the filter comprises a single or multi-layered folded or unfolded fabric filter, wherein the fabric comprises non-woven polymeric fibers. The water purification device of claim 6, wherein the filter has a composite filter that is non-woven and bonded to the activated carbon element.