MXPA98007528A - Method of treatment of a - Google Patents

Abstract

A method of treating water by adding to the water a stable composition of hydrogen peroxide itself and a polyquaternary ammonium compound, followed by intermittent treatment with a chlorine, bromine or oxygen-releasing compound

Description

METHOD OF WATER TREATMENT FIELD OF THE INVENTION The present invention relates in general to water treatment methods, and more particularly to a method of treating water with hydrogen peroxide, polyquaternary ammonium compounds and chlorine.

BACKGROUND OF THE INVENTION It is well established that water used in swimming pools, spas, hot or hot tubes, cooling towers, etc., quickly acquires a variety of microorganisms that can be harmful to human health. In addition, these microbes can damage structural materials, equipment, etc., in contact with water, and can compromise industrial processes which use water. Consequently, bioincruction or biological fouling is a significant problem for the regulated water industry, resulting in much attention being paid in the development of agents for the control of microbial growth in an aqueous medium.

REF .: 28438 Traditional biocides used for the control of microbial growth include chlorine, bromine, biguanide salts, peroxide compounds, ozone and quaternary ammonium compositions. Of these, chlorine has long been the dominant disinfectant, although the disadvantages of chlorine have led to a continuous search for other disinfectant products. For example, although chlorine is highly effective, it can be applied frequently to maintain this efficacy, and easily irritating forms of chloramines and / or trihalometamines. At high levels, chlorine can damage pool surfaces and equipment. Although chlorine and bromine levels can be maintained at levels of 1-3 ppm (such as Cl2), periodic superchlorination is often required to assess microbiological control and adequate water quality. Environmental hazards are associated with chlorine and the disadvantages associated with over-registration of mechanical feeders, necessary for a simplified, halogen-free alternative to water treatment. As previously indicated, peroxy compounds are known to be effective disinfectants under certain conditions. A problem associated with the use of these compounds, however, is such that peroxides such as hydrogen peroxide are not effective as a permanent only disinfectant except when used at relatively high concentrations (eg, 200 ppm higher). Unfortunately, the concentration of peroxide increases the likelihood of damage or discomfort for pool swimmers and bathers. When used in recreational waters, hydrogen peroxide supplies usually treat their products with compounds such as phosphates in order to stabilize the concentrated solutions. However, these stabilizers are not designated for affecting stability once the product has been applied to a body of water and diluted. Therefore, an additional stabilizer is necessary to protect and increase the peroxide, after the application. Like other disinfectants, quaternary ammonium compounds have been used in the treatment of water with some successors. The monomeric quaternary ammonium compounds are effective biocides. However, when quaternary ammonium compounds are used as primary disinfectants, high concentrations (25-75 ppm) are necessary. Different polyquaternarians, and monomeric quaternaries tend to produce substantially foam even at low concentrations (eg, 5 ppm). The foams will only be exacerbated at levels of 25 to 75 ppm.

When regulated waters are treated with H202, the system can only remain biocidally effective as wide as H202 remains available for disinfection. If levels of organic materials accumulate, the half-life of the peroxide decreases with a corresponding decrease in antimicrobial efficacy. It can be seen from the foregoing that there is a continuing need for water treatment methods with halogen-free disinfectants such as hydrogen peroxide and polyquaternary ammonium compounds, with and without the additional use of chlorine. The present invention is intended for this need.

BRIEF DESCRIPTION OF THE INVENTION Briefly describing the present invention, a water treatment method is provided by the use of strong oxidizing agents such as calcium hypochlorite, lithium hypochlorite, activated sodium bromide, sodium dichloroisocyanurate, trichloroisocyanurate, sodium hypochlorite, peroxymonosulphate potassium, etc. For regulating shocks of water treated with hydrogen peroxide (H202) and polyquaternary ammonium compounds "(policuat.) Superchlorination or super-oxygenation can assist these regulated waters in acceptable maintenance of water quality." In another aspect of the invention, provides a method of treating water by the addition of hydrogen peroxide and a polyquaternary ammonium compound to water.

The hydrogen peroxide and the polyquaternary ammonium compound are independently added to the water in effective amounts to maintain a balanced disinfectant solution in the water. An object of the invention is to provide a method of increasing or increasing the quality of regulated waters by using polyquaternary ammonium compounds, hydrogen peroxide and regulated strokes with liquid or dry oxidants. Another object of the present invention is to provide an improved method of water disinfected with dilute hydrogen peroxide. Another object of the present invention is to provide a method of adding flocculating and clarifying properties to diluted hydrogen peroxide solutions. Another object of the present invention is to provide a method of reducing the amount of hydrogen peroxide necessary to disinfect recreational or recreational waters.

Another object of the present invention is to provide a method of increasing the disintegration or half-life period of hydrogen peroxide used to disinfect recreational or recreational waters. Additional objects and advantages of the present invention will be apparent from the following description.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a graph of the estimates of the disintegration or half-life period of H202 with and without PDED.

Figure 2 is a graph of the estimates of half-life or disintegration time of H202 with and without DESCRIPTION OF THE PREFERRED MODALITY For the purpose of promoting an understanding of the principles of the invention, the reference will now be made to the preferred embodiments and a specific language will be used to describe them. In spite of everything, it will be understood that the non-limitation of the scope of the invention is intended, in such alterations and further modifications of the preferred embodiments, and additional applications of the principles of the invention as described herein will be contemplated as they could normally occur to one skilled in the art to which the invention pertains. In a preferred embodiment of the present invention, strong oxidizing agents such as calcium hypochlorite, lithium hypochlorite, activated sodium bromide, sodium dichloroisocyanurate, trichloroisocyanurate, sodium hypochlorite, potassium peroxymonoperoxide, etc. , are used to regenerate treated treated water with hydrogen peroxide (H202) and polyquaternary ammonium compounds (polyquaternary.). The addition of these materials destroys the organic materials and restores the half-life or disintegration time of the H202 close to its original level, effectively renewing the system from its original potency.

Thus, only small amounts of unstabilized chlorine, bromine, or oxygen releasing compounds are required for the specifications of the claimed method. In addition, the chlorine, bromine or oxygen releasing compounds need only be applied on an intermittent basis in order to regenerate the water. Preferably, a stable solution of H202 and a polyquaternary or polyquaternary) are added to a body of water to give concentrations of H202 within the range of 1-100 ppm and a polyquaternary concentration range of 0.1-30 ppm. Preferably, the level of H202 is of ranges of 10-30 ppm and the level of polyquaternary is of ranges of 1-5 ppm. The solution is preferably applied at specified intervals (once a week, twice a week or monthly). At certain intervals (weekly, twice a week or monthly), the super chlorination treatment or superoxygenation is applied before adding the polyquaternary solutions of H202. After several hours (if unstabilized or non-stabilized shock treatments are used), it is preferred to summarize the treatment program with another polyquaternary application of H202. Unstabilized chlorine products such as calcium hypochlorite, lithium hypochlorite are the preferred striking agents because the resulting chlorine residues will be rapidly degraded by ultraviolet radiation from the sun. Therefore, although superchlorination may be necessary for the system to maintain optimal performance, active chlorine will presently be present for relatively short periods of time.The same may be the same for activated sodium bromide.Bromide (such as sodium bromide) can be activated by hypochloric acid generated from bleach or dry oxidants in water It is surprising to maintain excellent water quality with such an uncommon use of a halogen shock treatment Stabilized chlorinating agents using a carrier of cyanuric acid (UV stabilizer) may be effective as unstabilized chlorine, but chlorine oxidant can remain active for long periods of time eriodos of time. Residual levels of chlorine may cause irritation to swimmers or could degrade water. Monoperoxysulfate is a chlorine-free alternative for people who want to avoid the use of halogens. Another aspect of the present invention uses diluted hydrogen peroxide as a disinfectant alone with a polyquaternary ammonium stabilizer to treat regulated waters. The stabilizer allows water to remain active biocide for long periods of time and increase its full effectiveness.The disinfectant and stabilizer can be added separately or mixed together by a slow single application.The ideal dose may comprise 1-2 gallons of the ingredients active (mixed or separated) to maintain 20,000 gallons of regulated water for two weeks The ability to effectively treat as such a large volume of water without mechanical feeders and with such infrequent dosing schedule is an unexpected disadvantage of the invention. of polyquaternary ammonium compounds can be used in various aspects of the invention including poly (hexamethylammonium) chloride ("06/6), poly [oxyethylene- (dimethylimino), ethylene- (dimethylimino) ethylene dichloride] (" PDED ") , dodecamethylenedimethylimine chloride ("Q6 / 12") and 1,3-diazo-2,4-cyclopentadiene with l-chloro-2,3-epoxypropane ("IPCP"). These and other polyquaternary ammonium compounds are available from common commercial sources. Preferably, the hydrogen peroxide and the quaternary ammonium compound are added independently so that appropriate concentrations of each composition can be maintained in the water. The appropriate Concentrations are generally determined by the evaluation of the treated water. Then, the appropriate amount of any composition can be added. This technique provides the additional benefit of allowing the two components to be stored and manipulated separately. In regular use, the water should contain between 5 and 4 ppm of H2O2 water and a polyquaternary ammonium stabilizer of concentration between 1 and 20 ppm. In order to treat 20,000 gallons, a mixed, concentrated product should contain between 105 and 80% H202 and 2% to 4% polyquaternary per gallon container. When applied as separate products, the relative concentrations of H202 and the polyquaternarians should remain in the same, using either a gallon or half gallon containers. As previously suggested, the various aspects of the present invention provide increasingly novel improvements, simple to the existing technique. First, the invention prevents the need to propose a mechanical device for applying the products. The cost of equipment and maintenance is thereby eliminated. Second, the invention is flexible in that the ingredients can be packaged as a stable mixture by itself or in separate containers. Third, the program of additions of the product can be adapted to suggest the needs of individual users of the pools. For example, more or less stabilizers may be required in certain cases and may be added without the addition of unnecessary amounts of another composition. Fourth, abandoning the mechanical device will become the most practical technology for consumers of regulated water treatment. Fifth, this system suggests the antimicrobial and aesthetic benefits of the polymeric and monomeric quaternary ammonium compounds. That is, a bio-effective effective system that produces only small amounts of foam, only. Sixth, the invention is superior to the polybiguanide system in that the components can be mixed in a container. In one aspect of the invention the polyquaternary ammonium compounds act as flocculants. Flocculants are chemicals that are used to degrade suspended solids from liquids, thereby facilitating their separation via precipitation or filtration. Consistent with this ability, polyquaternarians are capable of cell attachment and aggregation. Studies conducted in swimming pools with swimmers have shown that polyquaternarians such as Q6 / 6 are not viable to disinfect water when used alone. In such cases the bacterial densities were as high as 1 x 105 per milliliter. Due to the fact that the bacterial populations are high, the clarity of the water remains excellent. Table 1 shows a brief extract from the study in a pool in use.

Table 1. Bacterial density against water clarity Concentration Q6 / 6 BACTERIAL DENSITY TURBIDEZX (PPM) BY ML (NTU) 6 12,350 0.22 5 126,000 0.25 5 24,300 0.17 3 4,130 0.19 3 8,500 0.29 LNTU Nephelometric turbidity units.

A priority, you can expect the relationship between turbidity and bacterial density to be directly proportional. However, in the case where the bacterial population was as high as 126,000 / ml the clarity of the water remained excellent. A turbidity value below .32 NTU is considered clear. At 0.32 NTU or higher water is dangerous or cloudy. Based on the literature and the corroborated observations, it seems that the bacterium remains completely viable, but in aggregates that are difficult to obtain. This could explain the excellent clarity and the high bacterial density. Significant non-lethal alterations of the bacterial membrane may occur during the adhesion / aggregation process. These modifications could conceivably make an oxidant such as the H202 more accessible for critical areas of the cell membrane. In essence, polyquaternarians act as adjuvants or enhancers for H202. As a result, the kinetics of bacterial death could be improved as well as overcome efficiency. This could lead to significantly faster death rates and a decrease in the amount of H202 needed to disinfect the water. Reference will now be made to the specific examples using the procedure described above. It is well understood that the examples are provided to more fully describe the preferred embodiments, and that no limitation of the scope of the invention is attempted thereby.

EXAMPLE 1 In order to test the ability of several polyquaternarians to stabilize H202, five, 10 gallons of aquariums were filled with water and adjusted for the following parameters: approximately 200 ppm hardened calcium, 120 ppm alkalinity and pH 7.4. Each of the aquariums was dosed with 10 ppm of a different polyquaternary which consisted of Q6 / 6, PDED, Q6 / 12 or IPCP. Hydrogen peroxide (27.5 ppm) was added to the tanks containing the polyquaternaries and to a control tank that does not contain the polyquaternary. Each tank was tested daily with 25 ml of bacterial suspension (approximately 108 to 109 organisms) containing P. aeruginosa, E. coli, and S. aureus. These are some of the largest bacteria which can be recovered from recreational and industrial waters. The peroxide and polyquaternary concentrations were monitored after approximately 24 hours and recorded in Tables 2-6. In addition, the samples were removed 30 minutes after inoculation, treated with a neutralizer and placed on a nutrient agar to determine the number of viable bacteria.

Table 2. H202 as a single permanent disinfectant DAY PPM OF H202 TPC 1 34 20,350 2 11.9 692,000 3 4.25 752,000 42 1.7 1,1776,000 5 20.4 91,000 6 7.65 2,080,000 7 1.7 2,248,000 1 RPC - Counter of total heterotrophic plates (viable aerobic bacteria) expressed as a colony formed of units per mi. 2 Hydrogen peroxide (approximately 27.5 ppm) were added to each tank at the end of the 4 day.

Table 3. Effect of PDED on stability and efficacy of H202 DAY PPM DE H202 TPC 1 28.9 40 2 12.8 109 3 5.95 970 .4 3.4 500 24.7 220 11.9 3,000 8.5 4,950 Table 4. Effect of IPCP on Stability and Efficacy of H202 DAY PPM DE H202 TPC 1 32.3 0 2 13.6 0 3 6.8 0 4 2.6 1 5 24.7 2 6 17.85 3 7 7.64 38 Table 5. Effect of Q6 / 12 on Stability and Efficacy of H202 DAY PPM OF H202 TPC 32.3 0 12.8 0 7.7 3.4 11 27 22.1 10.2 Table 6. Effect of Q6 / 6 on Stability and Efficacy of H202, DAY PPM DE H: 2o2 TPC 1 31.5 3.040 2 12.8 475 3 6.0 1,070 4 2.6 11,750 5 19.6 23 6 16.2 2,000 7 6.8 4,800 The data presented in Tables 2-6 strongly suggest that classes of molecules known as polyquaternary ammonium compounds have the ability to stabilize and increase the efficiency of hydrogen peroxide. This is said, that H202 was more persistent in the presence of any of the plicuaternarios (increased stability) and the bacterial counts were greatly reduced (increased efficiency).

EXAMPLE 2 Since the trends were surprisingly observed during the aquarium experiments, additional experiments were performed in outdoor pools. The effectiveness of a combination of H202 with PDED and H202 alone was assessed in 5,000 pools with Hayward S-166T sand filters. Using standard pool chemistries, each pool was adjusted to approximately 120 ppm of alkalinity, 200 'ppm of hardened calcium and pH 7.4. In addition to receiving microbial inoculations from their environment, each pool was treated with bacterial suspensions (approximately 1010 and 1011 organisms) containing P. aeruginosa, E. coli, and S. aureus. Unlike the aquarium studies, the pools were subjected to UV radiation from the sun. Tables 7 and 8 summarize the results. Table 7 demonstrates the inability of H202 to control bacterial growth, even at high concentrations. In addition, the previous search has shown that PDED similar to H202 is not an effective disinfectant when used alone (data not shown). In contrast, Table 8 demonstrates the ability of polyquaternarians to increase H202, more efficiency is obtained. Meanwhile, the PDED has demonstrated the antimicrobial synergy with oxidants, these data indicate that the polyquaternaries can also stabilize and increase the disintegration time or half life of the peroxide in the use of dilutions. Table 7. H202 as a disinfectant only permanent DAY H202 PDED PM CFU / ML 1 26.35"" "" ~ 2 23.8"* 330 3 23.0 - 900 4 17.0 - 4,900 7 5.1 _ 51,000 8 0" "* 47,000 Table 8. Stabilization of H202 with PDED DAY H202 PDED PM CFU / ML 1 26.35 10 0 2 24.65 10 0 3 23.8 10 3 4 18.7 7 0 7 11.9 4 445 8 10.2 3 205 The data in Tables 7 and 8 were plotted for show the directions of the disappearance of H202 (Fig. 1). In addition, the data were subjected to a linear regression analy Table 9 was prepared using the statistics generated during the linear regression and showed that the PDED was able to extend or increase the type of disintegration or half-life of H202, even though the PDED concentration was as low as 3 ppm. Using the data, it can be extrapolated that the H202 alone, will be able to spend approximately 10.7 days, but it will be able to pass 14.2 when it is stabilized with PDED.

Table 9. Half life or disintegration time of H202 with and without PDED. STATISTICS H202 H202 + PDED Y-INTERCEPTED 31.04 28. 7 TILT -3.34 -2. 19 R ^ 0.978 0. 961 H202 half life or 5.35 7. 1 disintegration time (days) EXAMPLE 3 The experiment summarized in Example 3 is identical to Example 2, except that Q6 / 6 was replaced by PDED (Tables 10 and 11). Q6 / 6 alone is not an effective disinfectant in regulated waters (data not shown). As was the case with the PDED, the Q6 / 6 stabilizes and increases the efficiency of the H202. Hydrogen peroxide thus only tends to shorten the disintegration time or half life and is not such an effective bactericide even at the higher levels tested. Linear regression is collected in Table 12. Figure 2 graphically shows the difference in disintegration time or half-life. Based on the regression, it can be extrapolated that the H202 will only be able to pass for approximately 9 days, but it will be able to pass between 16 days when it stabilizes with Q6 / 6.

Table 10. H202 as a permanent only disinfectant DAY H202 PPM Q6 / 6 PPM CFU / ML 31.5 555 29.8 19,350 21.3 36,100 13.6 0.7 0.7 1,950 Table 11. Stabilization of H202 with Q6 / 6 DAY H202 PPM Q6 / 6 PPM CFU / ML 1 33.15 7 1 2 29.8 4 9 3 27.2 4 38 4 25.5 2 _ 5 17 1 6 14 1 46 Table 12. Disintegration or half-life time of H202 with and without PDED.

STATISTICS H202 H20 2 + PDED Y-INTERCEPTION 33.58 34.7 INCLINATION -3.95 -2.3 R¿ 0.96 0.99 - H202 HALF LIFE 0 TIME 4.52 7.9 DEBURRING (DAYS) The data clearly shows that a water treatment system based simply on H202 and a polyquaternary ammonium compound can achieve and maintain acceptable water quality. The fact that a gallon of mixed material could be used to treat up to 20, 000 gallons for up to two weeks constitutes a vast improvement over existing polybiguanide technology. The recreational waters disinfected with biguanide usually require the alternate addition of three different products: Biguanide, hydrogen peroxide and ancillary algicides. Biguanide is usually added for 10 to 14 days, the peroxide is added approximately for 20 to 30 days and the algicides are added once a week or as needed. The present method greatly simplifies the technique of biguanide in that the products are added at the same time and can be combined in a container. In essence, the application of the product is synchronized and one (mixed) or two (separate) products are used instead of the three. Additionally, since the method describes the prevention of the use of mechanized feeders, it offers sustained benefits for individuals involved in the treatment of regulated waters. This method allows for elimination of substantial costs, elimination of feeder problems and improved maintenance and efficiency due to the inherent flexibility of the packaging product applicants.

EXAMPLE 4 Table 13 shows the surprising effect that a chlorine stroke has a peroxide of disintegration time or half life. A previous 5,000 pool was kept in 10 ppm of H202 and 5 ppm of a polyquaternary (Q6 / 12) weekly. The pool was tested daily with a synthetic sweetener containing artificial isolates and a bacterial inoculum consisting of P. aeruginosa (109-10 cells). In addition, the pool received natural inoculations from the environment. In some cases, H202 was not measured due to weekend intervention. As indicated by the data in Table 13, a chlorine stroke allows H202 to remain active in the pool for a long period of time. Without a blow of chlorine, H202 remains in the pools for only 3 days. Chlorine extends the presence of peroxide for an additional 2 days. Differently expressed, a single stroke of chlorine extends the life of H202 by 67% TABLE 13 Effect of Chlorine on H202 and Q6 / 12 DATA H202 PPM AGGREGATE CHEMICALS /18/94 10 ppm H202 10/19/94 8. 5 10/20/94 5. 1 10/21/94 0 10/26/94 0 Calcium hypochlorite 10/27/94 10 ppm H202 10/28/94 7. 7 10/29/94 10/30/94 10/31/94 3. 4 11/01/97 0 11/16/94 10 ppm H2-02 11/17/94 11/18/94 EXAMPLE 5 In another experiment, a gallon of 5,000, in a previous round pool was treated with 27.5 ppm of H202 and 10 ppm of a polyquaternary (Q6 / 6) of a base once a week. No synthetic isolate or prepared bacterial inoculum was added since the human swimmers contributed the natural flora and secretions always in the pool to them. These swimmers (4) averaged between 2-4 hours per person per week in this particular pool. The data presented in Table 4 demonstrate the ability of a strong blow treatment to extend the life of H202. By the use of chlorine before adding the peroxide, H202 remains at detectable levels for 6 days. Without chlorine, the peroxide passes only for a maximum of 4 days. In this case, chlorine increases the life of H202 by at least 33%. However, H202 remains active for a long period of time even though a large amount of H202 is added during the subsequent addition (Table 14; 6 / 9-6 / 10). Similar results may be expected with strong oxidants such as activated NaBr (or other forms of oxidizing bromide), slurry, ozone, potassium peroxymonoperoxide, dichloroisocyanurate or trichloroisocyanurate.

TABLE 4 Effect of Chlorine on H202 and Q6 / 6 DATA H202 PPM AGGREGATE CHEMICALS 6/1/94 Sodium hypochlorite 6/2/94 20 27.5 PPM H202 6/3/94 6/3/94 6/4/94 6/5/94 6/6/94 6 6/7/94 2 6/89/94 0 6/9 / 94 19 27.5 PPM H202 6/10/94 16 10 PPM H202 6/11/94 6/12/94 6/13/94 The data in Tables 13 and 14 clearly demonstrate the amazing benefits of blow-by chlorination in the disintegration time or half-life of the hydroxide peroxide. Example 6, including Table 15, is further corroborated and expanded in these figures.

EXAMPLE 6 A gallon of 23,000 in a round in a pool was treated with weekly applications of H202 (30%) containing Q6 / 6 (0.5%) and PDED (1.5%). The rate of application maintained was 1.5 gallons per week and releasing 22.5 ppm of H202 and 2.25 ppm of polyquaternaries. In addition, 3 chlorine bars dissolved slowly were added for two weeks. A free residual chloride was not observed over time using the dissolved chlorine bars. As a comparison, typical chlorine bars are used at a range of 1 per 10,000 gallons and a free residual chlorine of 1-3 ppm should be maintained at all times. However, these bars can be completely dissolved within three to five days. Table 2 shows the beneficial effects of chlorination in blow on this system. At the beginning of this experiment, the applications of H202 result in theoretic (or far theoretical) levels of H202 in the pool (6 / 28-7 / 9). As the experiment progresses, the subsequent applications of H202 were substantially less productive (7 / 9- / 13). In order to restore the half-life of H202 to its original length, 6 gallons of H202 were needed within a period of four days even though the proportion of application maintained was only 1.5 gallons per seven days.

TABLE 15. Effect of Chlorine on H202 and Q6 / 6 and PDED DATA H202 PPM CHEMICALS AGGREGATED 6/28 0 30 PPM H202 6/29 25 6/30 20 7/1 7/2 15 7/3 5 7/4 2 22.5 PPM H202 7/5 20 7/6 10 7/7 5 7/8 2 7/9 0 22.5 PPM H202 7/10 5 7/11 2.3 30 PPM H202 7/12 10 7/13 0 37.5 PPM H202 7/14 25 7/27 0 22.5 PPM H202 7/28 15 8/1 2 8/2 1 8/3 0 22. 5 PPM H202 8/4 10 8/5 10 8/6 5 8/7 2 8/8 4 8/9 0 Sodium hypochlorite 8/10 0 8/11 0 22.5 PPM H202 8/12 15 8/13 10 As time surpassed, the maintained applications of H202 again failed to obtain theoretical levels (7 / 2-8 / 9). In addition, the use of slow dissolving chlorine bars does not effectively prevent the conditions that are responsible for the decrease in theoretical levels. However, the addition of 5 pounds of lithium hypochlorite in succession allows applications of hydrogen peroxide to obtain concentrations that reach the expected levels (8 / 9-8 / 13). At the time of the addition of H202, the pool still contained 2 ppm of free chlorine (8/11). H202 rapidly neutralizes free chlorine and is probably responsible for a lower H202 concentration than expected. Thus, superchlorination increases the H202 level by 33% over the initial pre-concentration (8/4 and 8/12). It is appreciated that the methods described above are particularly applicable for use in the treatment of swimming pool waters, as shown in the aforementioned examples. The methods can also be used, however, to treat water from spas or other recreational recirculating water sms, as well as to treat water from cooling towers, etc. While the invention has been described in detail, in the following description, it has been considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all the changes and modifications that fall within the scope of the invention. Fields of the invention are desired to be protective.

It is noted that, in relation to this date, the best method known by the Applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention. Having described the invention as above, the content of the following is claimed as property.

Claims (3)

1. A method of treating water, characterized in that it comprises the steps of: (a) providing hydrogen peroxide and at least one polyquaternary ammonium compound to a recirculating water system; and (b) intermittently adding to said water system an oxidizing agent selected from the group consisting of chlorine, bromine or chlorine-releasing compounds. oxygen.

2. The method according to claim 1, characterized in that said hydrogen peroxide and said polyquaternary ammonium compound are provided by the water supply of a composition itself stable, comprising hydrogen peroxide and at least one polyquaternary ammonium compound.

3. The method in accordance with the claim 1, characterized in that said chlorine, bromine or oxygen releasing compound is a member selected from the group consisting of calcium hypochlorite, sodium hypochlorite, activated sodium bromide, sodium dichloroisocyanurate, trichloroisocyanurate, sodium hypochlorite, sodium peroxymonosulphate. .