HK1009121B - Process and article for disinfecting water - Google Patents

Description

Method and article of manufacture for water disinfection

Technical Field

The field of the invention is the purification of water.

Due to worldwide population growth and industrialization, along with natural disasters, the supply of worldwide safe drinking water is declining. The key contaminants that pose a threat to humans from consuming contaminated water are pathogens (bacteria and viruses), organics, halogenated organics, and heavy metals, which in the united states home provide cleaner, pleasant drinking water by eliminating impurities from the water with a water filter. However, there are numerous limitations that make these systems difficult to apply, they are wasteful, bulky, difficult to install and replace, are hotbeds for the growth of harmful microorganisms, and are inconvenient, and while most of them are effective in eliminating some organics (including halogenated organics) and some heavy metals, none claims to eliminate or kill 100% of all pathogens.

Small disposable, e.g. in Brita^The so-called filter, which is too wasteful as measured by global standards and cumbersome to use, has one of the greatest disadvantages that it is designed on the premise of being used for water that is safe in terms of microorganisms. That is, the device is not designed to remove pathogens because it has been assumed that the water is free of pathogens. Furthermore, these devices have limited utility in removing harmful substances such as heavy metals.

For many people around the world, including travelers, it is difficult to obtain safe drinking without the cumbersome measures of boiling or disinfecting with iodine-based disinfectants. In many places, iodine-based disinfectants are not readily available, even if available, and it is known that certain iodine-based disinfectants leave an unpleasant taste in the mouth. Furthermore, since iodine is consumed, it may produce adverse drug effects, particularly in people with thyroid problems, and these methods are directed to removal anyway

Metals and organics are energetically inefficient.

Background

There are a number of iodine-based disinfectants for disinfecting drinking water that overcome the potential pharmaceutical difficulties caused by iodine consumption, one of which is manufactured under the trade name "Straw" by AccuFilter International inc. This device is an opaque tube that is inserted into the water to be disinfected. The tube is provided with an iodine-containing sterilising medium at its inner bottom end and activated carbon at a higher inner level, The bottom end being inserted into The water to be sterilised in use, The water being sterilised by passing through The iodine-containing medium during suction, The iodine-loaded water then passing through The bed of activated carbon, all iodine being removed, The producer of "The Straw" indicating that The water is sterilised after passing through The Straw and is substantially iodine-free. But still alert the thyroid problem to ask the physician before using the device.

Another device that is now available is manufactured by Recovery Engineering inc. This device is a tank with a plunger arrangement to force water through an iodine-based disinfectant to the effect that the effluent can be potted, as indicated in a product review by the outlide journal published in 8.1994, Pur Explorer which has been demonstrated by the EPA to inactivate all aquatic infectious agents, including viruses. This is achieved by the fact that during filtration the water passes through an iodine block, which also means that an optional carbonaceous core removes small amounts of iodine from the filtered water.

Yet another system that is currently commercially available is Wiconnin Pharmacal Co.Inc. of Jackson Wisconsin under the trade name of Table Aqua^And p.a.plus are marketed. In this system, 2 separate tablets are added sequentially to the water to be purified, one tablet Aqua being added to 1 quart of water to be purified^(2 tablets were added when flagellates were suspected) the active ingredient of the tablet was tetraglycine hydroperoxide iodide (16.7%), i.e. each tablet contained 6.68% titratable iodine. Potable Aqua^The tablets were dissolved in water and held for 10 minutes (20 minutes in the presence of giardia pyriformis) at which time the water was slightly orange, then a tablet of p.a was addedPlus tablet to eliminate iodine odor brought into water by the Potable Aqua. The active ingredient of the p.a. plus tablets was ascorbic acid, 45 mg per tablet of p.a. plus, after addition of the p.a. plus, the water was shaken for another 3 minutes, after which the water turned clear and was drinkable. Of importance is a Table Aqua^And p.a. plus cannot be added simultaneously, the p.a. plus tablet must be added after a 20 minute expiration, otherwise harmful microorganisms may remain in the water. Clearly, this system involves the sequential addition of 2 tablets.

While all of these devices do address the bad taste associated with iodine-based disinfectants and the concomitant problem of drugs that may be generated by the large amounts of iodine that are consumed, none of them provide the consumer with a one-step product that provides a reliable visual indication after the disinfection process is completed and safe for consumption. Although a Table Aqua^P.a. plus does give a visual indication that the water has been purified but that the iodine evolved in the first step of the prescribed time period has been removed. In other words, regardless of which product the consumer must believe that the product has worked and that the water is indeed safe to drink. Importantly, if a Potable Aqua is used^With the p.a.plus system, it is difficult to determine when the water is safe to drink without a separate timing watch.

From the foregoing, it is clear that a one-step method and article of manufacture that allows consumers to know that water has been sanitized without relying on an external timing mechanism, i.e., a method and article of manufacture that provides a visual indication that the water has been safely potable after the purification process has been completed, is needed.

Disclosure of Invention

The present invention is intended to overcome the above-mentioned problems, this object having been solved by a method for disinfecting water according to independent claims 1 and 8 and by articles according to independent claims 17, 21, 26 and 27.

Further advantages, features, aspects and details appear from the dependent claims, the description and the drawings. The claims are to be understood as a first non-limiting method of specifying the invention in general terms.

The present invention broadly refers to the purification of water, which is to be broadly construed to include disinfection or elimination of harmful contaminants or both.

In a general aspect, the present invention provides a method of disinfecting drinking water, which is characterized by allowing a consumer to know from a visual inspection that the disinfection process has been completed and the water is safe to drink.

Another general aspect of the present invention is to provide an article that is capable of disinfecting water and provides a consumer with a visual target when the water is completely disinfected and safe to drink.

These and other aspects and broad applicability of the present invention will become apparent to those skilled in the art from the details given herein. It should be understood, however, that the detailed description of the presently preferred embodiments of the invention, while indicating preferred embodiments of the invention, is given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

In response to the difficulties that have been encountered by those skilled in the art, a method of disinfecting water has been devised which gives a visual indication after disinfection has been completed. First, the water being disinfected is mixed at least simultaneously with three things: (1) at time T_kA disinfectant capable of rendering harmless all pathogens present in the water; (2) a colorant; and (3) a time T for passing all of the disinfectant and colorant in the water_rSubstantially removed material, here T_rGreater than T_k. The inclusion of a colorant, which naturally gives rise to a color of the water, indicates that the disinfection process has begun. Of course, the colorant does not reflect the presence or absence of pathogens, and secondly, allows the combined water, disinfectant, colorant and scavenging material to maintain T_rOr longer, at T_rAt the end, all pathogens in the water will be substantially harmed and all disinfectants and colorants will be substantially eliminated. The removal of the colorant results in the water becoming colorless, which gives the consumer the benefit ofAn indicator that water has been disinfected is safely consumed, in other words, the consumer does not have to be concerned about the time required for disinfection because at T_rThe water will have color in time due to T_rGreater than T_kSo the disappearance of the colour indicates that the disinfection of the water is also completed.

In some examples, the disinfectant may be selected from a group including one or more of iodine, halohydrazone, phenol, or ammonium compounds. If the disinfectant is iodine, it may be an iodine compound such as tetraglycine hydroperoxide iodide or colloidal iodine.

In certain examples, the colorant may be selected from a range of one or more including iodine, edible colorants, or grape tannins. As such, in some instances, one material may function as both a disinfectant and a colorant. One of the materials that has this dual purpose is iodine.

Alternatively, the colorant may be a food grade colorant, such as FD& C Blue ^#1 or FD& C Red^#40。

In some examples, the material used to remove the disinfectant and colorant is selected from a group including one or more of activated carbon, zeolite, or clay.

Examples of pathogens as targets of destruction include vibrio cholerae, piricollis, cryptosporidium, salmonella, fecal escherichia coli, respiratory enteroviruses, adenoviruses, human enteroviruses such as poliovirus, hepatitis a virus, and coxsackie virus.

In some instances, the method may include other water treatment steps while disinfecting.

For example, treatment may include adding useful substances to the water, such as health-promoting or color-enhancing; alternatively, the treatment may be directed to the removal of harmful substances other than disinfectants and colorants.

If a substance is added during the treatment step, this substance may be selected from a group comprising water-soluble vitamins, minerals, micronutrients and colouring agents. Exemplary water-soluble vitamins that may be added include the B vitamins and vitamin C, and exemplary minerals that may be added include calcium, magnesium, potassium, sodium, iron, or phosphorus. Exemplary micronutrients may include, additionally, zinc and copper. An exemplary color enhancer is starch.

If a material is to be removed in the treatment step, this material may include heavy metals, organics, halogenated organics, polyaromatics and halogenated polyaromatics. It is particularly desirable to remove the pesticides and herbicides present with the effluent contamination. Exemplary heavy metals to be removed in the treatment step include lead, nickel, mercury, copper and arsenic.

The invention also relates to an article for disinfecting water and providing a visual indication after disinfection, the article comprising: (1) at a contact time T when the article is placed in water_kA disinfectant capable of rendering substantially all pathogens in the water substantially harmless; (2) a colorant; and (3) a contact time T of the product with water_rAnd then substantially removing all disinfectants and colorants from the water. Here T_rGreater than T_k。

In some embodiments, the article will also include a treatment material for treating water in contact with the article. By adding or removing one or more substances from the water. In some instances, the treatment material may also both release and scavenge different substances.

In one example, the article comprises a water-permeable pouch defining at least 1 interior compartment containing: (1) one after the bag is immersed in water T_kA disinfectant that is capable of substantially detoxifying all pathogens present in the water over time; (2) a colorant; and (3) a bag capable of standing at T after immersion in water_rMaterial that removes all disinfectants and colorants in the water over time, here T_rGreater than T_k。

In some embodiments, the chamber will also include a treatment material that is used to treat the water with which the article is contacted, the material releasing or removing one or more substances. In some instances, the treatment material may also both release and remove different substances. Of course, the bag may also have more than one interior compartment, each containing one or more components of the product. For example, the bag may have 2 internal chambers, one containing the sanitizing agent, the other containing the colorant and the scavenging material. Naturally, an example of a bag with more than 2 interior chambers is also conceivable.

In some examples, the water permeable material of the bag may be selected from abaca paper or viscose.

Drawings

The invention will be better understood by considering the following description of an example in conjunction with the accompanying drawings, in which:

FIG. 1 is a first embodiment of the present invention, the article being a wafer.

Figure 2 is a bleached view of the first example.

Fig. 3 is a second embodiment of the present invention wherein the disinfecting agent, coloring agent and eradicating material are placed in a pocket.

Fig. 4 is a second example in which the pocket of fig. 3 is in use.

Fig. 5 is another embodiment of the present invention.

Fig. 6 is a graph showing the level of iodine in water according to experiment 1.

Fig. 7 is a graph showing the level of iodine in water according to experiment 2.

Fig. 8 is a graph showing the level of iodine in water according to experiment 3.

The invention is capable of use in a wide variety of embodiments, only a few of which are described in detail herein, including the best mode presently contemplated. In general, the present invention relates to a disposable, disposable product and method that provides users with sanitized water and also provides users with visual indicators of when the water is potable at the completion of the sanitization process. By way of example, the pathogen to be destroyed is selected from one or more of Vibrio cholerae, Verbenomycota pyriformis, Cryptosporidium, Salmonella, fecal Escherichia coli, respiratory enteroviruses, adenoviruses, human enteroviruses such as poliovirus, hepatitis A virus, and Coxsackie disease.

Turning now to the drawings, wherein like numerals indicate like items or method steps, and more particularly to FIG. 1, a first embodiment of the invention is illustrated in the figure 10 as a wafer, the wafer product 10 being placed in a sterilized water 14 contained in a container 12.

The wafer 10 is formed from a mixture of ingredients including: (1) a water-soluble disinfecting agent which, when the article is contacted with water 14, causes substantially all of the pathogens therein to be present at time T_kThe inner part is innoxious; (2) a colorant; and (3) a T-value after the product has been contacted with water 14_rMaterial capable of eliminating disinfectant and coloring agent completely in time, here T_rGreater than T_k. As the amount of disinfectant, colorant and scavenging material will vary with the amount of water 14 contained in the container. The disks should therefore be of different sizes and the maximum amount of water that can be handled satisfactorily for each result is indicated, it being understood that the disk 10 may contain inert ingredients such as conventional fillers and binders to enable the aforementioned three ingredients to be formed into a disk, the composition of the disk 10 being such that it disintegrates rapidly into small particles when plunged into the water 14 and subjected to gentle agitation.

One skilled in the art will readily recognize that many disinfectants may be used in the present invention. For example, the disinfectant may be selected from iodine, iodine compounds such as tetraglycine hydrogen periodide, halazone, phenols or quaternary ammonium compounds.

Similarly, a plurality of colorants may be used in the present invention, for example, the colorant may be selected from one or more of iodine, an edible colorant or grape tannin, or the colorant may be a food grade colorant, such as commercial FD& C Blue^#1 or FD& C Red^#40。

Similarly, the scavenging material, i.e., the material that scavenges the disinfecting agent and the coloring agent, may be selected from any material that generally absorbs, adsorbs, or neutralizes the disinfecting agent and the coloring agent. That is, the scavenging material may be an adsorbent, absorbent or a neutralizing agent. If an adsorbent is present, it may be selected from one or more of activated carbon, zeolite or clay; if the scavenging material is a neutralizing agent, it may be selected from ascorbic acid and sodium thiosulfate.

It should be clear to those skilled in the art that in some instances, one material may serve two purposes. For example, one material that serves both as a disinfectant and a colorant, and one that serves a dual purpose is iodine.

Next, the water 14 in the container 12 is gently stirred for a few minutes to allow the disk 10 to disintegrate into countless small particles and to mix well with the water 14. This is naturally done in order to achieve a good distribution of the disinfectant, colorant and scavenger material in the water 14, the result of the uniform distribution of the colorant in the water 14 being a colouring of the water 14.

The wafer 10 will be designed to contain sufficient water soluble disinfectant. Enough to be used for a relatively short time T_kA specified maximum amount of water is consumed meso, which amount should be known to the skilled person. For example, I is known at a concentration of two parts per million (2ppm)₂Four parts per million (4ppm) I will disinfect water in about 40 minutes₂The water will be disinfected in about 20 minutes. In addition, the colorant will be selected to eliminate material reaching T_rIt cannot be removed all the time ago, and T_rRatio of T to_kLong. The result of this arrangement is that the water 14 will remain colored until disinfected. The user/consumer can therefore judge whether the water is completely disinfected by visually observing the indicator, i.e. whether the color in the water has disappeared.

Of course, the removal material has removed the disinfectant there as the water disinfection is carried out, that is to say the removal material is at T_rThe double tasks of removing the coloring agent and the disinfectant are completed within the time.

Turning to fig. 2, once the colour has disappeared from the water 14, the user/consumer waits for the particles 16 of the disc 10 to fall to the bottom of the container 12 before the water 14 can be drunk. Alternatively, the particles 16 may be separated from the water 14 by decanting or filtering. Since no disinfectant is left in the water, the disinfected water risks heavy contamination and should therefore be drunk within a few hours.

Fig. 3 illustrates a second embodiment of the present invention, the method of operation being substantially similar to that described with respect to fig. 1 and 2. Except that in the second embodiment the disinfecting agent, colorant and scavenging material are contained in a water permeable hydrophilic pouch 18 which is structurally and functionally equivalent to a tea bag which is water permeable, the operation of this embodiment being substantially the same as with the disc 10 except that all of the material is readily removed from the water after the disinfecting process is completed. In this example, the water 14 is disinfected just as tea is brewed, except that no external heat is used, and the disinfecting agent and coloring agent are reabsorbed or neutralized. That is, the pouch 18 is immersed in the sterilized water 14 of the container 12, the water 14 is agitated slightly to facilitate mixing, and the pouch 18 is lifted out of the water 14 after the color is removed, and FIG. 4 is an illustration of the pouch 18 used.

In some instances, some of the components may be contained within (blended with) a water-permeable hydrophilic material that will be near the surface of the bag 18 and will more readily escape into the water. In this embodiment, the scavenging material remains in the pocket 18, and the incorporation of some or all of the other components in the water-permeable hydrophilic material allows the other components to have a "head start" for the scavenging material. That is, the other components can be dispersed to a greater extent into the water to accomplish their intended function before contacting the scavenging material. Incorporation of the disinfecting agent into the water permeable material allows the disinfecting agent to increase in concentration more quickly before the scavenger begins to scavenge it, in such instances, faster disinfection appears to occur because of the higher initial concentration of the disinfecting agent in the water.

In other instances, it is believed that the water being consumed is free of pathogens and has one or more harmful substances, and that the pouch 18 of the present invention is free of disinfectants, i.e., the pouch 18 is provided with only suitable scavenging material or scavenging material plus any desired treatment material.

Fig. 5 is an illustration of yet another embodiment of the present invention. For example, fig. 5 illustrates an article 20 that is used in a sterilization process and includes a fabric 22, 22 containing a disinfectant and a colorant, the article 20 also including a container 24 inside which is attached a fixed form of a cleaning material 26, wherein, in use, the water 14 to be sterilized is disinfected and colored by the fabric 22, and then the cleaning material 26 within the container 24 (e.g., at the bottom) removes the disinfectant and colorant from the water.

Of course, in some simple examples, all 3 components may be held together in an open pocket, and in use the contents of the pocket are poured into sterile water, leaving an empty pocket which is either discarded or refilled with the appropriate three components. In one example, such a pocket may also be utilized as a filter to separate water from remaining removal material.

It will be apparent to those skilled in the art that various changes and modifications can be made in the present invention. For example, when water is treated in some way during sterilization, the product for sterilization must be modified accordingly.

In this regard, the treatment may add substances to the water that promote health and/or enhance the coloring agent. Alternatively, the treatment may be to eliminate potentially harmful substances other than disinfectants, colorants, which may be digested, i.e., organics, heavy metals, halogenated organics, polyaromatics, halogenated polyaromatics, pesticides, herbicides, and the like.

If a substance is added, the added substance can be added to a product (wafer, tea bag, etc.) as a water-soluble additive. Thus, when the article comes into contact with water during the sterilization process, the additional substance will dissolve in the water and be digested by the consumer. Of course, care should be taken to ensure that the material is not removed to a great extent. If a substance is added during the treatment step, it may be selected from water-soluble vitamins, minerals, micronutrients and colouring agents. Exemplary water soluble vitamins that may be added include one or more of vitamin B and vitamin C. Exemplary minerals that may be added include calcium, magnesium, potassium, sodium, iron, or phosphorus. Exemplary micronutrients that may be added include zinc and copper. One example of a color enhancer is starch. Starch is a color enhancer for iodine. In water purified by disinfection or other methods, the presence of starch greatly darkens the color of iodine present, low concentrations of iodine in water, if at all, are nearly colorless, and the addition of starch magnifies the color to the naked eye. Naturally, there are also other materials that can amplify the color of iodine or the color of another colorant.

If a substance is to be removed in a processing step, the scavenging material used to remove the disinfectant and colorant may also be effective for it. Or if the scavenging material is not effective in scavenging the extraneous species that it is desired to remove by absorption, adsorption or neutralization, an additional treatment for the extraneous species may be required.

If a material is to be removed in the treatment step, the material may be selected from the group consisting of heavy metals, organics, halogenated organics, polyaromatics, and halogenated polyaromatics. It is particularly desirable to remove pesticides and herbicides as a result of drainage pollution. Examples of heavy metals to be removed in the treatment step are lead, nickel, mercury, copper and arsenic.

Other additives may include binders, selected vitamins, minerals and/or flavors. Within a few minutes of gentle stirring, the disinfectant kills bacteria and viruses while the solid adsorbent adsorbs organics, including halogenated organics. Heavy metals can also be adsorbed if a suitable solid adsorbent is selected. The solid adsorbent also removes residual disinfectant and color indicator by adsorption. The disappearance of the color indicator (at the point where the water clears) indicates that substantially all pathogens have been killed, that substantially all disinfectants have been adsorbed or neutralized, and that substantially all organic contaminants have been removed. This water, with or without solid particles present, can be stored for many hours prior to consumption. The product may also release calcium, magnesium, vitamin C or any other healthful vitamin or mineral or flavor over a useful period of time via controlled release or other mechanism.

Those skilled in the art will appreciate that the release of the disinfecting agent, colorant, scavenging material, and treatment material (if present) may be designed as desired. For example, the scavenging and/or treatment materials may be encapsulated in a substance that is slowly soluble in water, such that the scavenging and/or treatment materials are exposed to water for a predetermined time depending on the thickness of the encapsulating material. In particular, the disinfectant and colorant may be released first to indicate to the consumer that the disinfection process is proceeding. Release of the scavenging material should be delayed until the desired concentration of disinfectant is reached and release of the treating agent (if present) for additive purposes should be delayed until shortly before the colorant is adsorbed or neutralized by the scavenging material, thus reducing the potential for removal of the additive material by the scavenging material.

For example, the scavenging material may be encapsulated or coated with a water soluble material that dissolves slowly in water to delay its activity, after the coating dissolves away, the scavenging material begins to eliminate the disinfectant. This gives the disinfectant time to reach the required concentration for disinfection before it is removed.

Detailed Description

Experiment No. 1 was conducted to demonstrate that activated carbon contained in a water permeable pouch can remove iodine from a sample of water in a sufficiently short period of time to make the present invention commercially viable.

5 15.24 cm (6 inch) square pockets were made with 21gsm heat sealable teabag paper (16 grams per square meter) (manufactured by Kimberly Clark Corp. of Dallas, under the trade name BHS 555). Each bag contained 20g of activated Carbon manufactured by Calgon Carbon Corp. of Pittsburgh under the trade name F816 (8X 16 mesh). The pocket was filled with 2 liters of distilled water containing 32ppm iodine, which also served as a colorant here to give the water an orange color. This water was continuously agitated with a stir bar and, at specified times as set forth in Table 1, 25mL samples were subsequently analyzed by titration (Skoog, West and Holler, Fundamentals of analytical chemistry. p.780, published in Saunders College Publishing 1988) over 3 minutes, FIG. 6 is a plot of the data of Table 1 showing that the level of iodine in the water dropped nearly linearly to the lower limit of the sensitivity of the assay, 0.9ppm within 10 minutes, and the water became clear, with an analytical error range of +/-1 ppm.

TABLE 1 activated carbon/iodine test

Time (minutes)	Titrant mL Na2S2O3(0.001mol)	Iodine molarity	Iodine ppm
				0.00.41 12.03.05.07.010.0	6.35.85.14.32.81.851.20	0.0001260.0001160.0001020.0000860.0000560.0000370.0000240	32.029.425.921.814.29.46.1ND*

Not tested for ND

Experiment No. 2 was performed to determine the effect of the bagged disinfectant (iodine) regimen on the concentration of the disinfectant in water.

In experiment 2, 2 pockets identical to experiment 1 each hold 50g of activated carbon. 8 bactericidal sheets (product of Wilson pharmaceutical Co. Inc. of Jackson Wiscosin, trade name of Table Aqua) were added^) Also placed in a bag after crushing, such tablets containing 16.7% by weight of tetraglycine hydrogen periodide, 50 tablets of gaseous Aqua^Weighing 5.95g (0.21 in two). Each bag therefore contained 0.16g (0.0056 engbi) of tetraglycine hydrogen periodide. Seal and place 2 liters of distilled deionized water within 5 minutes of tablet crushing. The water and bags were agitated continuously with a stir bar, and 25mL samples were taken at intervals as listed in Table 2 and analyzed as described above within 3 minutes, Table 2 showing that the iodine concentration in the water first increased to about 4ppm within 2 minutes and then decreased to below 0.9ppm within about 7 minutes. FIG. 7 is a plot of Table 2.

TABLE 2 activated charcoal/iodine experiment (tablets and activated charcoal in bags)

Time (minutes)	Titrant mL Na2S2O3(0.001mol)	Iodine molarity	Iodine ppm
				00.20 51.02.03.04.35.37.08.51.01.3	00.60.350.450.730.370.250.250000	00.0000120.0000070.0000090.00001460.00000740.0000050.0000050000	ND3.01.82.33.71.91.31.3NDNDNDND

Not tested for ND

This experiment demonstrates that the water permeable pouch material limits the maximum concentration of iodine. It is likely that the close proximity of the recycled material to the sterilised iodine also provides a significant deterrent to the maximum concentration of iodine achieved. These factors must be kept in mind when considering how much material the bag will contain in commercial use, and must ensure that the concentration of iodine reaches a level that enables sterilization and that level is maintained for a period of time before it is removed by the scavenging material.

Experiment No. 3 further provides evidence of the effect of bag material and the close proximity of disinfectant to scavenging material on the maximum iodine concentration achieved, in experiment No. 3, 16 potabeaqua' s^Tablets were crushed as in experiment No. 2, ground and mixed with 100g of activated carbon as described in experiment 1, the tablets and activated carbon were added to 2 liters of distilled water within 3 minutes after grinding, continuously stirred with a glass rod and successively sampled at intervals as listed in table 3, titration analysis was performed within 3 minutes after each sampling, and the analytical procedures were as before and the results of the experiments are reported in table 3. Indicating that the level of iodine in the water reached about 8ppm at 1 minute and then dropped nearly linearly, 2.4ppm after 3 minutes and to less than 0.5ppm after about 7 minutes. FIG. 8 is a plot of Table 3.

TABLE 3 activated charcoal/iodine experiment (neither tablets nor activated charcoal are bagged)

Time (minutes)	Titrant mL Na2S2O3(0.001mol)	Iodine molarity	Iodine ppm
				00.20.51.02.03.04.05.07.0912	01.51.51.10.750.480.340.18000	00.000030.000030.0000220.0000150.00000960.00000680.0000036000	ND7.67.65.63.82.41.70.9NDNDND

Not tested for ND

Experiment No. 4 was done to elucidate 16 Potable aquaes^In the absence of scavenging material, the iodine concentration rose rapidly and 16 tablets were dissolved in 2 liters of distilled water without the addition of activated charcoal. Within 2 minutes after the addition of the tablet, the solution was analyzed as described above and found to contain 32.7ppm iodine, from which the effect of the bag material and scavenging material was seen.

It will be understood that various changes and modifications may be made without departing from the scope of the invention. It should also be understood that the scope of the invention should not be construed as limited to the particular examples disclosed herein, but rather construed according to the below claims.

Claims (26)

1. A method of disinfecting water which gives a visual indication after completion of the disinfection, characterized in that said method comprises the steps of:

mixing water with a disinfectant for a period of time T_k，T_kSufficient to render harmless all pathogens present in the water with a disinfectant;

mixing water and a colorant with each other;

mixing water with one energy at T_rMixing all disinfectant and colorant removed from the water over a period of time, wherein T_rShould be greater than T_k；

Wherein said water, disinfectant, colorant and said material are mixed with each other for a period of time T_rOr longer;

wherein said material for removing disinfectants and colorants from the water is selected from the group consisting of activated carbon, zeolite, or clay;

so that all pathogens present in the water are rendered harmless and all disinfectants and colorants are eliminated.

2. A method according to claim 1, characterized in that said disinfectant is selected from the group consisting of solid iodine, iodide, haloaminzone, phenol or quaternary ammonium compounds.

3. A process according to claim 2, characterized in that the iodine compound is tetraglycine hydrogen periodide.

4. A method according to claim 1, characterized in that said coloring agent is selected from iodine, edible coloring agents or grape tannins.

5. A method according to claim 1, characterized in that the pathogen is selected from Vibrio cholerae, Giardia pyriformis, Cryptosporidium, Salmonella, fecal Escherichia coli, respiratory enteroviruses, human enteroviruses such as poliovirus, hepatitis A virus and Coxsackie virus.

6. A method of disinfecting and treating water and providing a visual indication after disinfection is complete, said method comprising the steps of:

providing water;

mixing water and a disinfectant for a time T_k，T_kSufficient to render harmless all pathogens in the water with a disinfectant;

mixing water with a colorant and a treatment material;

mixing water with one at T_rThe scavenging material capable of removing all the disinfectant and colorant during the time T_rGreater than T_k；

Wherein the water, disinfectant, colorant and the scavenging material are mixed with each other for a period of time T_rOr longer; and

so that all pathogens in the water are rendered harmless and all disinfectants and colorants are removed, whereupon the water is treated.

7. A method according to claim 6, wherein said treatment material is employed to add at least one additional substance to the water.

8. A method according to claim 7, wherein the added substance is selected from vitamins, minerals, micronutrients or colour enhancers.

9. The method according to claim 8, wherein the vitamin is one or more selected from vitamin B and vitamin C.

10. The method according to claim 8, wherein the mineral is one or more selected from the group consisting of calcium, magnesium, potassium, sodium, iron, and phosphorus.

11. A process according to claim 8 wherein the micronutrient is one or more selected from the group consisting of zinc and bell.

12. The method of claim 6, wherein the treatment material is used to remove at least one substance from the water.

13. The process of claim 12 wherein the treatment material is used to remove one or more materials selected from the group consisting of heavy metals, organics, halogenated organics, polyaromatics, and halogenated polyaromatics.

14. The method of claim 13, wherein said heavy metal is selected from the group consisting of lead, nickel, mercury, copper, and arsenic.

15. An article for disinfecting water and providing a visual indication when disinfection is complete, the article comprising:

a disinfectant which is suitable for use when the product is in contact with water to cause all pathogens present in the water to be present at time T_kThen is innoxious;

a colorant;

a solid adsorbent which is adapted to be capable of standing for a time T when the article is in contact with water_rDuring which all disinfectants and colorants in the water can be removed, wherein T_rGreater than T_k。

16. The article of manufacture of claim 15 wherein the solid adsorbent is coated with a water soluble coating.

17. The article of claim 15, further comprising a treatment material.

18. The article of claim 17 wherein the treatment material is coated in a water soluble coating.

19. The article of claim 17, wherein the treatment material is used to add at least one substance to water that is in contact with the article.

20. The article of claim 17, wherein the treatment material is used to remove at least one substance from water that is in contact with the article.

21. An article for disinfecting water and providing a visual indication when disinfection is complete, the article comprising:

a pouch formed of a water permeable material, the pouch having an interior cavity containing:

a disinfectant is prepared by soaking bag in waterAll pathogens at time T_kThen is innoxious;

a colorant; and

a solid adsorbent is prepared by soaking bag in water at T_rAll disinfectants and colorants in the water can be removed in time, wherein T_rGreater than T_k。

22. The article of claim 21, wherein the chamber further contains a treatment material.

23. The article of claim 21, wherein the treatment material is at least one substance added to the water when the article is contacted with the water.

24. The article of manufacture according to claim 21, wherein the treatment material is used to remove at least one substance from water when the article of manufacture is contacted with water.

25. The article according to claim 21 wherein the water permeable pouch material is selected from abaca paper or viscose.

26. An article for disinfecting water and providing a visual indication after disinfection is complete, the article comprising:

a pocket made of a water-permeable material containing a disinfectant for treating the T-cell after immersion of all pathogens present in the water_kAfter the time, the mixture is completely innoxious;

the permeable material forms an inner cavity containing:

a colorant; and

t after bag is soaked in water_rA solid adsorbent capable of substantially completely removing all disinfectants and colorants in water over time, wherein T_rGreater than T_k。