JP2004500348A - Concentrated bromine aqueous solutions and their preparation - Google Patents

Abstract

The thickened liquid germicidal composition is produced by a continuous process. The step comprises continuously feeding (i) an aqueous solution of bromine chloride and (ii) an alkali metal salt of sulfamic acid into a mixing device. They produce an aqueous product having an active bromine content of at least 100,000 ppm (w / w) and an atomic ratio of nitrogen to active bromine from (i) and (ii) of greater than 0.93: 1. With a proportion. The desired product thus formed continuously is withdrawn from the mixing device at a flow rate sufficient to maintain a continuous feed. Thus, product withdrawal can be continuous or intermittent, depending on the type of mixing equipment used. In various aspects of the invention, the bromine chloride is supplied separately from the bromine and chlorine by maintaining these streams under automatic feed flow control where the streams are continuously proportionedly mixed to form bromine chloride. Generated continuously from the flow of goods.

Description

[0001]
(background)
Bromine-based disinfectants have proven advantageous as disinfectants for chlorination-dechlorination for microbiological control of cooling water and disinfection of waste treatment systems. The water treatment industry has confirmed that these benefits can be controlled inexpensively at higher pH values, have little loss of fungicidal activity in the presence of ammonia, and are effective regulators of bacteria, seaweeds and molluscs are doing.
[0002]
A common method of introducing bromine-based germicides into aqueous systems is through the use of aqueous NaBr with NaOCl bleach. The user supplies both substances to a common point, where NaOCl converts bromide ions to HOBr / OBr.^(-)To oxidize. The activation solution is then introduced directly into the aqueous system to be treated. HOBr / OBr^(-)The supply of two liquids in such a process is necessary because the mixture is unstable and must be generated in situ shortly before its introduction into water. Furthermore, the supply and metering of the two liquids is cumbersome, especially since the system must be given time to cause the activation of bromide ions. As a result, many disinfectant users have expressed a need for a single supply of bromine-based disinfectant. Bromine chloride molecules appear to meet these needs. It is liquid at room temperature and can be fed directly into an aqueous system where immediate hydrolysis occurs to produce HOBr.
[0003]
BrCl + H₂O → HOBr + HCl
Bromine chloride is a fuming red liquid or gas having a boiling point of 5 ° C and a vapor pressure of 1800 mm at 25 ° C. It corrodes most metals in the presence of water. It can be seen that certain properties of bromine chloride-especially its corrosiveness, high vapor pressure and smoke propensity-require attention and skill in its handling and use.
[0004]
An economically acceptable method of stabilizing a high concentration aqueous bromine chloride solution is described in US Pat. No. 5,141,652 to Moore et al. The solution is prepared from bromine chloride, water and a halide or hydrohalic acid. These solutions have been found to degrade at a rate of less than 30% per year and, at high halide salt concentrations, at a rate of less than 5% per year. In addition, a solution could be prepared containing 15% equivalents of bromine of the element. Unfortunately, the relatively high acidity of these solutions and their tendency to corrode and smoke limits their economic acceptability.
[0005]
WO 99/62339, published Dec. 9, 1999, discloses, inter alia, a novel method for forming a concentrated aqueous solution of bactericidal active bromine, wherein the bromine or bromine chloride is dissolved. It provides a new and significantly more effective concentrated sterile aqueous solution. These solutions are formed by a process comprising (a) mixing bromine or bromine chloride with (b) an aqueous solution of an alkali metal salt of sulfamic acid (preferably a sodium salt), wherein the solution formed is at least 7, having a pH in the range of 7 to 14, for example. The amounts of (a) and (b) used are (i) the content of active bromine in the solution is at least 100,000 ppm (weight / weight) and (ii) the nitrogen from (a) and (b) It is used such that the atomic ratio of active bromine is greater than 0.93 and preferably greater than 1.
[0006]
(Summary of the Invention)
One object of the present invention is to provide a method of co-owned WO 99/62339 not only in a commercially viable manner but also in an exceptionally efficient manner on a continuous basis. Is to be able to do it. Another object is to use the method of WO 99/62339 in which at least a portion of the bromine chloride is produced continuously and used as one of the continuous feeds, on a continuous basis. It is also not only possible to implement in a commercially efficient and extremely efficient manner, but also to enable these methods to include efficient automatic continuous process control. Other purposes can be recognized below.
[0007]
In one of its aspects, the present invention provides a method for producing a concentrated liquid sterilizing composition, the method comprising:
A) An active bromine content of at least 100,000 ppm (w / w) and an alkali metal salt of (i) bromine chloride and (ii) sulfamic acid (preferably sulfamine) of more than 0.93: 1 (preferably more than 1) Continuously feeding (i) and (ii) into the mixing device in such a ratio as to produce an aqueous product having an atomic ratio of nitrogen to active bromine from an aqueous solution of the sodium salt of the acid). And
B) withdrawing the product from the mixing device at a flow rate sufficient to maintain a continuous feed in A);
Comprising.
[0008]
In a preferred embodiment, the aqueous solution of the alkali metal salt of sulfamic acid is present in said mixing device, which is supplied with bromine chloride. In another preferred embodiment, the aqueous solution of the bromine chloride and the alkali metal salt of sulfamic acid is continuously fed into the mixing device and the product is sufficient to maintain a continuous feed. Withdrawn from the mixing device at a flow rate.
[0009]
In another embodiment, the bromine chloride is formed continuously from bromine and chlorine, and at least a portion of the continuously produced bromine chloride is used as the continuous feed of bromine chloride in step A) above. Bromine chloride itself is formed by the reaction of equimolar amounts of bromine and chlorine. Therefore, when forming bromine chloride, equimolar amounts of bromine and chlorine can be used. However, this is not necessary because an excess of stoichiometric bromine can be used and is specifically used. Although excess chlorine in excess of the stoichiometric amount can be used, it is less preferred because the germicidal product will contain chlorine groups with less bactericidal activity than active bromine groups. Thus, in addition to what is required to maintain the continuous feed of step (A) (i) above, in plant facilities where bromine chloride is needed or desired for one or more uses. Can scale up the continuous production of bromine chloride to assist in all of these uses. In the continuous production of bromine chloride, the use of a stoichiometric excess of bromine relative to chlorine produces a mixture of bromine chloride and bromine. These mixtures are very suitable for use in the production of a concentrated liquid disinfecting composition according to the invention.
[0010]
A preferred embodiment comprises, in addition to steps A) and B) described above, the following simultaneous operation: continuously but from at least one of the at least two reaction vessels and then at least one of the other ones Alternately withdrawing the aqueous solution of the alkali metal salt of sulfamic acid at a flow rate that maintains said flow of A) (ii), and during that time, the solution from said at least one of said at least two reaction vessels And then forming a further aqueous solution of an alkali metal salt of sulfamic acid in the other of said at least one of the at least two reaction vessels from which the solution has not been withdrawn. Thus, the aqueous solution of the alkali metal sulfamate salt forms A) (ii) while forming a larger amount of such a solution in one or more other tanks ("one or more tanks II"). Can be continuously withdrawn from one or more tanks ("one or more tanks I") so that when one or more tanks I are empty, the system Is switched to one or more tanks II, which then serve as feed for the continuous supply of A) (ii) until empty, and by then a larger amount of their solution Are formed in one or a plurality of tanks I. Thus, by switching supply and production from one tank (or group of tanks) to another tank (or group of tanks) and reciprocating between tanks filled as feed, alkali metal A continuous supply of the aqueous solution of the sulfamate can be maintained without substantial interruption.
[0011]
A particularly preferred embodiment of the present invention is
A) Separate feed streams of (i) the bromine chloride stream identified in C) below and (ii) the aqueous solution of the alkali metal salt of sulfamic acid identified in D) below at least 100,000 ppm. An active bromine content of (weight / weight) and a ratio which produces an aqueous product having an atomic ratio of nitrogen to active bromine from (i) and (ii) of greater than 0.93, continuously in the mixing device Supplying,
B) withdrawing the aqueous product from the mixing device at a flow rate sufficient to maintain a continuous feed in A);
C) contacting bromine and chlorine continuously in a vessel in equimolar or near equimolar amounts, and specifically containing a stoichiometric excess of bromine to produce bromine chloride; And continuously withdrawing a stream of a bromine chloride product specifically containing excess bromine from the vessel at a rate maintaining the feed of (i) in A), wherein the bromine chloride product is At least a portion of the stream comprises the stream of bromine chloride of (i) of A), and
D) Sequentially, but alternately from at least one of the at least two reaction vessels, and then alternately from at least one other, at a flow rate that maintains the flow of (ii) in A), the alkali metal of sulfamic acid Withdrawing the aqueous solution of the salt and during that time withdrawing the solution from at least one of the reaction vessels, further adding the alkali metal salt of sulfamic acid into at least one other reaction vessel from which the solution has not been withdrawn. Forming an aqueous solution;
A method comprising:
[0012]
In one of its aspects, the present invention provides a method for producing a concentrated liquid sterilizing composition, the method comprising:
a) The stream is continuously proportional with an stoichiometric excess of bromine, specifically containing excess bromine, to form equimolar or near equimolar amounts and specifically bromine chloride. Continuously forming bromine chloride from separate feed streams of bromine and chlorine by maintaining said stream under automatic feed flow control to be mixed;
b) The feed stream has an active bromine content of at least 100,000 ppm (w / w), a pH of at least 7, and nitrogen to active bromine atoms from (i) and (ii) above 0.93: 1. Separate the aqueous solution of (i) the bromine chloride formed in a) and (ii) the alkali metal salt of sulfamic acid under automatic feed flow control which is continuously proportionally mixed in an amount to produce an aqueous product having a ratio. Of the active bromine at a rate of at least 100,000 ppm (w / w), a pH of at least 7, and a nitrogen to active bromine of greater than 0.93: 1. Continuously forming an aqueous product having an atomic ratio; and
c) withdrawing the aqueous product from the mixing device at a flow rate sufficient to maintain the continuous feed in a) and b);
Comprising. Preferably the automatic feed flow control in a) and b) is under nested cascade ratio flow control.
[0013]
Since the reaction between bromine chloride and the alkali metal sulfamate solution is an exothermic reaction, the temperature of the aqueous product being formed does not exceed about 50 ° C, and is preferably in the range of 25 ° C and 40 ° C. It is desirable to control the temperature of the reaction so that it is, and most preferably, maintained at about 30 ° C. Such control can be achieved, for example, by immediately passing the effluent from the mixing device through a proximally located heat exchanger to remove excess heat from the effluent. Another method of implementing such temperature control is to suitably add an aqueous solution of the alkali metal sulfamate before it reaches the mixing device, such that the temperature of the effluent stays within the above temperature conditions. Cooling. Both of these methods of temperature control can be used as desired.
[0014]
Another embodiment of the above method comprises, in addition to steps a), b) and c) above, the reaction of sulfamic acid with an alkali metal base, such as an alkali metal hydroxide, in water to give an alkali. Including periodically or continuously forming an aqueous solution of a metal sulfamate.
[0015]
One preferred embodiment of the above process is the following simultaneous operation, i.e. successively but from at least one of the at least two reaction vessels and then alternately from at least the other one of b) (Ii) withdrawing the aqueous solution of the alkali metal salt of sulfamic acid at a flow rate that maintains the flow of, and during that time withdrawing the solution from at least one of the at least two of the reaction vessels, at which time the solution Forming a further aqueous solution of an alkali metal salt of sulfamic acid in at least one of the other reaction vessels that has not been withdrawn. Thus, the aqueous solution of the alkali metal sulfamate forms b) (ii) while forming such solutions in one or more other tanks ("tank or tanks II") in larger amounts. ) Can be continuously withdrawn from one or more tanks (“one or more tanks I”) so as to serve as a continuous supply of The system is switched to one or more tanks II, which then serve as a feed for the continuous supply of A) (ii) until they are empty, and by then a larger quantity of them Are formed in one or more tanks I. Thus, by switching supply and production from one tank (or group of tanks) to another tank (or group of tanks) and reciprocating between tanks filled as feed, alkali metal A continuous supply of the aqueous solution of the sulfamate can be maintained without substantial interruption.
[0016]
Another preferred embodiment of the above method is the following simultaneous operation: continuous withdrawal of an aqueous solution of the alkali metal salt of sulfamic acid from the circulating inventory of the alkali metal salt of sulfamic acid, where The withdrawal is at a flow rate that maintains the flow of b) (ii)), and the aqueous solution of the alkali metal salt of sulfamic acid is at least periodically in an amount sufficient to maintain at least their circulating inventory. Continuously replenishing a circulating inventory from a feed of such an aqueous solution of an alkali metal salt of sulfamic acid from the reaction vessel produced. By maintaining a circulating inventory of an aqueous solution of an alkali metal salt of sulfamic acid in a pump on a circulation loop, such a solution can be prepared from sulfamic acid, an alkali metal base such as an alkali metal hydroxide, and water. Only one reaction vessel is required to form.
[0017]
The above and other aspects and features of the present invention will become more apparent from the following description, appended drawings and / or appended claims.
[0018]
(More detailed description of the invention)
Various types of mixing devices can be used in the practice of the present invention. In one preferred embodiment, the mixing device comprises a static mixer. Static mixers continuously receive a continuous feed stream of an aqueous solution of bromine chloride and an alkali metal sulfamate salt, and from those feed streams that are substantially uniform in composition and thus meet product specifications. Any suitable design and configuration can be used as long as the formed mixture can be continuously discharged.
[0019]
Another preferred mixing device comprises a container with a mechanical stirrer. In this case, the vessel receives a continuous feed stream of an aqueous solution of bromine chloride and an alkali metal sulfamate salt, and continuously or substantially receives a substantially homogeneous mixture formed from these feed streams. Discharges intermittently. The mechanical stirrer can be programmed to operate continuously or intermittently, as long as the output from the vessel is constant and substantially uniform in composition. Thus, if the discharge from the container is intermittent, the incoming continuous feed is preferably agitated for at least the majority of the time filling the container to a predetermined volume. At that point, the discharge is stopped so that the contents of the container are drained earlier than the total incoming feed until the container reaches a predetermined low volume, at which point the container begins to refill. On the other hand, if the filling is continuous, the system is such that the total inflow volume to the vessel and the simultaneous outflow volume from the vessel are maintained equal and the vessel is in front of the contents being mixed by the mechanical stirrer. Thus, the predetermined capacity is continuously included and configured. In such a case, the stirrer is preferably operated continuously.
[0020]
Bromine chloride is a maintained, preformed bromine chloride that can be supplied from a storage tank. Preferably, however, the bromine chloride is co-prepared from equimolar or near equimolar amounts of bromine and chlorine, and specifically continuously using an excess of bromine, in a suitable corrosion resistant reaction vessel. You. As described above, the amount of bromine chloride that is continuously produced is, unless otherwise necessary or desired, an additional amount of bromine chloride and the amount of bromine chloride that is continuously supplied to the mixing device. Can be equal. However, if other demands or desires exist, the amount of bromine chloride produced can be scaled up to meet such demands or desires. Bromine chloride is specifically equimolar or near equimolar, and specifically in excess of bromine, to contact the reactants and maintain the mixture temperature within the range of 10-50 ° C. Formed by
[0021]
The use of bromine chloride as a source of active bromine in concentrated, stable liquid sterile preparations produced according to the present invention is highly advantageous. When such a disinfectant preparation is used to treat water, all the bromine of the bromine chloride is made available as active bromine in the resulting highly diluted solution. In other words, the chlorine of the bromine chloride is converted into dissolved alkali metal chloride salts during the process, thereby releasing bromine as well as the active bromine content of the germicidal composition. Thus, the more expensive component of bromine chloride, i.e., bromine, is fully used for active bromine formation in aqueous germicidal compositions, and at the same time, the relatively inexpensive component, anionic chlorine in bromine chloride, has this beneficial effect. Make it possible.
[0022]
The term "active bromine", of course, means all bromine-containing groups capable of bactericidal action. In general, all bromine in the +1 oxidation state is bactericidal and is therefore accepted in the art as being included in the term "active bromine". As is well known in the art, bromine, bromine chloride, hypobromite, hypobromite ion, hydrogen tribromide, tribromide ion, and organic-N-brominated compounds have bromine in the +1 oxidation state. . Thus, these, as well as their other groups to the extent they are present, constitute the active bromine content of the compositions of the present invention. See, for example, U.S. Patent Nos. 4,382,799 and 5,679,239. A well-established method in the art for determining the amount of active bromine in a solution is a starch-iodine titration, which comprises all the activities in a sample, regardless of which group constitutes active bromine. Determine the bromine. The utility and accuracy of the classical starch-iodine method for the quantitative determination of bromine and many other oxidants has been described by Willard-Furman,Elementary Quantitative Analysis, Third Edition, D.A. Van Nostrand Company, Inc. , New York, Copyright 1933, 1935, 1940, has been known for some time as evidence.
[0023]
A typical starch-iodine titration to determine active bromine is performed as follows. Put a magnetic stirrer and 50 milliliters of glacial acetic acid into the iodine flask. A sample to determine active bromine (usually about 0.2-0.5 g) is weighed and added to the flask containing acetic acid. Next, water (50 milliliters) and an aqueous potassium iodide solution (15% (weight / weight), 25 milliliters) are added to the flask. The flask is stoppered using a water ring. The solution is then stirred for 15 minutes, after which the flask is uncapped and the stopper and sealed area are rinsed into the flask with water. An automatic buret (Metrohm Limited) is filled with 0.1N sodium thiosulfate. The solution in the iodine flask was titrated with 0.1N sodium thiosulfate. When a slight yellow color was observed, 1 milliliter of a 1% by weight aqueous starch solution was added, and the color of the solution in the flask was changed from slightly yellow to blue. Change to The titration with sodium thiosulfate is continued until the blue color disappears. The amount of active bromine is calculated using the weight of the sample and the volume of sodium thiosulfate solution titrated. Thus, the amount of active bromine in the compositions of the present invention can be determined quantitatively, regardless of the actual chemical form.
[0024]
The aqueous solution of the alkali metal salt of sulfamic acid (alkali metal sulfamate) can be pre-formed and fed from a storage vessel to the mixing device as another continuous feed is fed. However, it is preferred to simultaneously produce these aqueous solutions at a flow rate sufficient to at least continuously supply the amount required to maintain these continuous supplies to the mixing device. If other demands or desires of these aqueous solutions exist, the volume of solution produced can be scaled up to meet those demands or desires.
[0025]
An aqueous solution of an alkali metal salt of sulfamic acid is also formed in a dry state by mixing a dry water-soluble alkali metal base and dry sulfamic acid, and then the solid, resulting dry mixture is mixed with water You can also. Further, an aqueous solution of an alkali metal salt of sulfamic acid can be formed by mixing an aqueous solution of an alkali metal base and dry sulfamic acid. However, the aqueous solution of an alkali metal sulfamate is preferably formed by mixing together a slurry of sulfamic acid in water and a solution of a water-soluble alkali metal base.
[0026]
Any water-soluble inorganic alkali metal base can be used to form an aqueous solution of the alkali metal sulfamate. Examples of these bases include oxides, hydroxides, carbonates, bicarbonates, acetates, sulfates and the like. Any water-soluble basic salt or oxide of an alkali metal can be used, but the sodium salt or oxide is preferred. However, potassium salts or oxides are also very useful. A mixture of two or more water-soluble sodium bases, a mixture of two or more water-soluble potassium bases, or a mixture of one or more water-soluble sodium bases and one or more water-soluble potassium bases can be used. . Highly preferred are aqueous sodium hydroxide solutions which can be formed from sodium oxide or sodium hydroxide. Specifically, the aqueous solution will contain an alkali metal base in the range of 10-55% by weight, but any concentration of these bases that can form an aqueous bromine chloride solution that meets the pH requirements of the present invention. Can also be used.
[0027]
In addition to having an active bromine content of at least 100,000 ppm (w / w), the concentrated aqueous alkali metal sulfamate solution discharged from the mixing device preferably has a pH of at least 7, for example a pH in the range of 7-14. And preferably has a pH greater than 7 and up to about 14. Most preferably, the solution is an overbased alkali metal sulfamate solution having a pH in the range of 13.0 to 13.7. The pH of the concentrated germicidal solution is specifically governed by the pH of the aqueous alkali metal sulfamate solution used as the feed to the mixing device.
[0028]
The solution discharged from the mixing device has a pH lower than the desired value, and further base can be supplied to the solution after discharging the mixing device to raise the pH to the desired value. Alternatively, separate aqueous solutions of alkali metal bases can be simultaneously and continuously fed to the mixing device to achieve a more alkaline (basic) concentrated product solution that drains the mixing device. . However, neither of these latter two methods is a preferred method of operation.
[0029]
Thus, in a preferred mode of operation, the rate of the continuous feed stream of aqueous solution of bromine chloride and alkali metal sulfamate to the mixing device is such that (i) the content of active bromine in the solution of the product formed is At least 100,000 ppm (w / w) and (ii) the atomic ratio of nitrogen to active bromine from these feed streams is greater than 0.93, and more preferably from 1.0 to about 1.4. Is within the range.
[0030]
The use of bromine chloride in conjunction with caustic in the stabilized bromine composition achieves higher levels of active halogen compared to the level obtained by adding sodium hypochlorite to sodium bromide can do. The method and the composition formed also have an active bromine content that is about twice that of most thickening solutions produced according to Goodenough et al., US Pat. No. 3,558,503. Furthermore, even at the high levels of active bromine present in the compositions of the present invention, these high levels of active bromine are maintained for at least two months, and during this period, visible or unpleasant vapors or odors are eliminated. It has been discovered that a germicidal composition not shown can be provided.
[0031]
In each embodiment of the invention, the operation is preferably such that the concentrated product solution produced in the process is in the range of 120,000 ppm weight / weight (12% by weight) to 180,000 ppm weight / weight (18% by weight). Of the active bromine content. Furthermore, in each embodiment of the invention, the atomic ratio of nitrogen to active bromine in the concentrated product solution is preferably at least 1: 1, for example in the range of 1.1 to 1.5. Higher ratios can be used if desired. A particularly preferred atomic ratio is 1.0: 1 to 1.4: 1.
[0032]
One of the features of the present invention is to provide an aqueous germicidal composition that is free or essentially free of bromide, even if unpurified. In other words, no matter what bromide is present, its amount, determined by use of the test method described below, is such that the concentrated aqueous germicidal composition of the present invention is based on the total weight of the concentrated aqueous germicidal composition. On the basis of 50 ppm (weight / weight) or less (i.e., not exceeding). In fact, in the preferred concentrated aqueous germicidal compositions of the present invention, the bromide content is in the range of 0 to about 40 ppm (weight / weight) as determined using these test methods.
[0033]
As known in the art, bromide is a highly undesirable component of aqueous systems. For example, U.S. Pat. No. 5,922,745 issued a 1995 paper by the U.S. Environmental Protection Agency examining some health concerns related to bromide formation (G. Amy, et al.,Water Supply, 1995, 13 (1), 157), and in the same year, the carcinogenicity of animals correlated with the presence of low levels of bromide in drinking water (JK Falwell, and G. O'Neill,Water Supply, 1995, 13 (1), 29). Some prior art treatments have achieved a reduction in the amount of bromide formed during the production of stabilized aqueous bromine-containing fungicides, but the need for a further reduction in the amount of bromide present in these fungicides is required. Still remains. According to the invention, these further reductions have been made possible. Further, for the present invention, at least 100,000 ppm (weight / weight) that today are free or essentially free of bromide, as well as free or essentially free of bromide, since its inception. ), And preferably having an active bromine content in the range of 120,000 to 180,000 ppm (weight / weight). Thus, the potential for exposure to bromide is reduced during all stages of production, processing, storage, transportation and use of these compositions. To the best of our knowledge, it was not possible to achieve such a result before the present invention. In addition, the treated water generally has a weight / weight amount in the range of 0.5 to 20 ppm in an aqueous medium which is treated for fungicidal and / or biofilm control. Bromine (B₂And preferably in the range of 4 to 10 ppm of bromine (B₂Is usually sufficient, the addition of a germicidally effective amount of active bromine thereto results in substantial dilution of the water treated according to the invention. This in turn means that very little, if any, bromide present in the concentrated aqueous solution of the present invention will be present in the water being treated while achieving the microbiological control for which the composition is used. , Which means that it is sharply reduced in units of several dimensions.
[0034]
The analytical test method used to determine the concentration of bromide (if present) in the compositions of the present invention is an ion chromatography method using UV detection. The equipment required to carry out the method is as follows.
a) Ion chromatography with UV detector and automatic sampler-Dionex DX-500 or similar,
b) Data Acquisition and Analysis Device-VAX MULTICHROM or similar chromatography data acquisition and processing system;
c) Ion chromatography column-Dionex IonPac AG9-HC protection column (p / n051791) in series with Dionex IonPac AS9-HC column (p / n051791);
d) Mespipet-any standard type of appropriate volume,
e) Automatic sampling vial-for 1 mL with lid,
f) volumetric flask-100 mL,
g) Syringe-5cc plastic syringe,
h) Pretreatment cartridge-OnGuard-H from Dionex (p / n039596).
[0035]
The chemicals required for use in this method are:
a) water-deionized water having a resistivity of 17.8 megohm-cm or more;
b) Sodium carbonate-"Baker Analyzed^(R)"Reagent grade or similar,
c) Sodium bromide-"Baker Analyzed^(R)"Reagent grade or similar.
[0036]
The conditions used for ion chromatography are as follows.
Eluent: 4.5 mmol (mM) sodium carbonate,
Flow rate: 1.0 mL / min,
Injection volume: 50 microliter (μL),
Range of detector: UV at 210 nanometers (nm).
[0037]
The eluent is prepared by dissolving 0.4770 grams of sodium carbonate in one liter of deionized water. These are mixed well and the solution is filtered through a 0.2 IC compatible filter to degas the solution. A concentrated bromide standard solution is prepared by weighing 0.1180 grams ± 0.001 grams of sodium bromide in a 100-mL volumetric flask and diluting to volume with deionized water. This produces a solution containing 1,000 micrograms of bromide per milliliter. The concentrated bromide solution must be refreshed at least weekly. The bromide working standard solution is prepared by pipetting 100-milliliter of the concentrated bromide standard solution into a 100-mL volumetric flask and filling the flask to volume with deionized water. Thorough mixing of the solution produces a standard concentration of 1.0 microgram of bromide in 1 milliliter.
[0038]
The detailed method used to perform the analysis of the aqueous solution of the invention involves the following steps.
a) Weigh 0.25 grams of sample solution into a 100-mL volumetric flask. Fill to volume with deionized water and mix well.
b) Flush the OnGuard cartridge with 2-mL deionized water.
c) Fill a 5-mL sample into a syringe attached to an OnGuard cartridge and pass at a flow rate of 2 milliliters per minute, discarding the first 3 milliliters. Collect in 1-mL automated sampling vials and cap for analysis.
d) Double the injectate and analyze the sample using the conditions of the ion chromatography instrument given above.
[0039]
The calculations involved in the method are as follows.
a) Criteria for setting the scale: For bromide, calculate the reaction coefficient as follows: R = A / C [where R is the reaction coefficient and A is the average area number (two times) And C is the concentration of micrograms per milliliter (μG / mL)].
b) Sample, bromide ppm = A (R x W), where A is the average area of the sample peak (two injections), R is the reaction coefficient, and W is the weight of the sample in grams. is there].
[0040]
The process of the present invention is a continuous process, involving a continuous feed to the mixing device. In addition, some embodiments of the present invention provide for the continuous formation of bromine chloride, or the continuous contact of bromine and chlorine to form bromine chloride, or another amount of a solution of at least one other such bromine chloride. While forming in such a vessel, it involves a continuous alternating withdrawal of an aqueous solution of an alkali metal salt of sulfamic acid from at least one reaction vessel. In these embodiments, the term "continuous" or "continuously" does not mean to exclude interrupted supplies or withdrawals. In general, if such interruptions occur, they are short-lived, do not substantially affect the steady-state operation of the overall process, and produce a significant amount of off-specific enrichment. In such a way that no product solution is produced. An example of such a slight, non-detrimental interruption is the operation whose operation is to be carried out from at least one reaction vessel mentioned above as part of a "continuous" feed and another such reaction vessel. This may occur when switching the flow of the aqueous solution of the alkali metal salt of sulfamic acid to the vessel. Unless such a switching operation disrupts the operation or results in the formation of a significant amount of off-specified concentrated product solution, such interruptions are acceptable and within the spirit of the term "continuous". is there. As used herein, the term "continuous" does not permit interruption, i.e., in any step or process, where both continuous and discontinuous (e.g., "intermittent") processing are explicitly mentioned. Has an exception. One example of this exception is the manner in which the product is continuously withdrawn from the above-mentioned container with a mechanical stirrer. These "continuous" drawers are, in another aspect explicitly mentioned herein, because the withdrawal of the same product from the same container is specifically described as being "intermittent". Not interrupted. Thus, both alternations (continuous and discontinuous) are explicitly mentioned herein.
[0041]
Reference is now made to FIG. 1 of the drawings, which is largely self-explanatory.
[0042]
In the plant flow diagram depicted in the scheme in FIG. 1, separate equimolar or near equimolar streams of bromine and chlorine are fed, preferably continuously, into a stirred jacketed reactor 10. . The contents of reaction vessel 10 are specifically maintained at a temperature in the range of -30C to 30C such that bromine chloride is preferably produced continuously. The bromine chloride is continuously conveyed into the mixing device 20. A 15-25% by weight aqueous solution of sulfamic acid, sodium hydroxide and water are simultaneously charged into either the jacketed reaction vessel 30 or the jacketed reaction vessel 40, and the resulting mixture is stirred and stirred. Maintain at ５０50 ° C. Proportionally mixing the sulfamic acid and sodium hydroxide produces an aqueous sodium sulfamate solution having a pH preferably in the range of 13.0 to 14.0 in the reaction vessel. At that time, the unused reaction vessels 30 or 40 for preparing these aqueous sodium sulfamate solutions contain therein the same aqueous solution previously produced in a similar manner. Such a stream of sodium sulfamate aqueous solution is continuously withdrawn from the reaction vessel 30 or 40 (as the case may be) containing the previously prepared solution, and this stream is continuously fed into the mixing device 20. Is done. The interaction between bromine chloride and the sodium sulfamate solution tends to be exothermic. Therefore, it is desirable to cool the mixture while it is being formed, especially in large facilities. The effluent from the mixing device 20 is a thickened, stable aqueous sterile preparation. This product solution is transferred from the mixing device 20 to a storage tank 50 or equivalent container such as a diesel or tank truck. If the mixing device 20 is a static mixer, the effluent from the static mixer is continuously transferred to the storage tank 50. On the other hand, the mixing device 20 is for example a vessel with a mechanical stirrer, and the vessel is drained intermittently so that its contents oscillate between the high and low contents of the product solution. In such a case, the transportation of the product solution from the mixing device 20 to the storage tank 50 is intermittent. Electrically operated so that a continuous, alternating flow of the aqueous sodium sulfamate solution from one of the reaction vessels 30 and 40 and then the other to the mixing device 20 can be maintained continuously. Means such as associated electronics for sensing and transmitting when one valve is closed and one valve closed while the other is open (not shown) are included.
[0043]
(1) a 15-25% by weight aqueous solution of (1) sulfamic acid, (2) sodium hydroxide, and (3) alternately reciprocating between one of the reaction vessels 30 and 40 while the other reaction vessel is drained. 1.) Instead of the separate feeds of water represented in FIG. 1, separate streams of aqueous sodium hydroxide solution and a preformed aqueous slurry of sulfamic acid can be alternately fed to these reaction vessels. it can. It can be expected that other variations and details on the plant flow diagram and / or method of operation according to the illustrated scheme will now be readily apparent to one of ordinary skill in the art.
Automatic process flow controller
In the practice of the present invention, various process aspects are implemented by the automatic process flow control device described below. An exemplary flow diagram with such an automatic process flow controller is shown by the schemes in FIGS. Both of these flow diagrams use similar methods to simultaneously supply bromine, chlorine and sodium sulfamate. The difference between the two figures is that FIG. 2 requires two containers. The first vessel is used to neutralize sulfamic acid to sodium sulfamate. The second vessel is used as a supply tank for continuously supplying sodium sulfamate to the remaining steps. The flow diagram of FIG. 3 is a "1-pot" process that uses a single reaction vessel to continuously neutralize sulfamic acid and supply sodium sulfamate to the remaining steps.
[0044]
The following process description with respect to FIGS. 2 and 3 uses feedback process control logic. Descriptions of specific device elements are provided herein to help better understand how the logic steps work.
[0045]
The feedback control loop (for flow control) has three components: (1) a sensor device for measuring the flow, (2) a control valve for changing the flow, and (3) for maintaining the desired flow. A flow control device for instructing the control valve to open or close as required.
[0046]
The Micro Motion Coriolis mass flow meter has been used in past processes with the indicated flow rate accuracy and is described in the process description below. These devices are available from Micro Motion, Inc. USA, 7070 Winchester Circle, Boulder CO 80301. These specific instruments use the Coriolis method to provide a direct mass flow indication (for volumetric flow indications that must be converted to mass units and corrected for temperature fluctuations) and further controlled by a control system. A flow signaling device used to provide a feedback flow signal to a computer of the same. The size specification of the mass meter depends on the desired flow rate, density / viscosity characteristics of the flowing liquid, and the magnitude of the pressure drop inherent in the associated piping.
[0047]
Specific automatic control valves are pneumatically operated to raise / lower the stem in the valve body. A precisely machined, uniquely contoured "trim" is attached to the stem and resides in the flow path in the valve body. The trim serves to vary the size of the flow orifice as the stem moves up and down. The size of the trim is defined to provide a specific flow range for a constant pressure drop over the valve. The pneumatic activation signal specifically converts an electrical signal from the controller (typically measured in milliamps in the 4-20 mA range) to a corresponding pneumatic signal (typically measured in gauge pressure in the 3-15 psig range). Provided by the I / P device used for Barometric pressure is supplied to the I / P device, which in turn provides the correct pressure to operate the valve. The I / P device is typically tuned to the 0-100% scale of the 4-20 mA electrical signal to accommodate the 3-15 psig barometric pressure signal at the 0-100% scale of the desired flow range (ie, 4 mA = 3 psig = 0). Flow, 20 mA = 15 psig = 100% flow). Illustrations of I / P devices have been omitted from the proposed flow diagram as they are generally assumed to be necessary. The specific valve sizing will depend on the choice of the desired pressure drop over the valve, pipe size and trim to provide the desired flow range. Control valves for 1/2 "to 1" diameter process lines are specifically described by Badger Meter, Inc. Industrial Division, 6116 East 15th St. , Tulsa, OK 74158.
[0048]
The controller is the heart of the control loop and is typically an electrical "black box" in the control system computer software. Most controllers are of one of three types, proportional (P), proportional integral (PI) or proportional integral derivative (PID). The name reflects what type of response action is taken to adjust the control signal. A detailed description of each type is not provided herein. Most flow control loops use a PI controller due to the nature of the flow measurement and the immediate response of the control valve.
[0049]
The overall feedback control loop works as follows.
The desired flow value (set point) is input to the controller. A sensor device measures the current flow (measured variable) and returns the current flow value to the controller. The controller calculates the error between the measured variable and the desired set point value. Next, the controller sends signals to the I / P and the control valve to control the position of the control valve for either increased or decreased flow to minimize the error between the actual and desired flow values. (Variables manipulated). The determination of how quickly or how much to change the position of the control valve depends on the tuning parameters supplied to the controller for the proportional-integral response. The control loop is "tuned" by changing these parameters to achieve an optimal response (minimization of error) to process malfunctions or set point changes.
[0050]
The steps of FIGS. 2 and 3 use a nested cascade ratio flow controller to continuously produce a concentrated liquid disinfectant composition. Cascade ratio controllers use a feedback control loop. For this type of control, the flow of the primary material is controlled at the desired flow set point. A flow transmitter that provides a feedback response to a controller, commonly referred to as a master controller, also issues a flow signal to a ratio controller. This signal is the set point of the flow control of the second substance stream, and hence the term cascade. This controller, commonly referred to as a slave controller, provides a signal to a control valve that controls the flow rate of the second substance stream. The flow element of the second stream measures the flow and returns a signal to the ratio flow controller. The secondary controller calculates the error between the measured flow value and the remotely supplied set point. Next, the secondary controller provides a signal to change the second control valve to maintain the secondary flow as a ratio of the primary flow.
[0051]
The flow controllers are typically included as individual building blocks within the operating software of the process control computer system. A specific control system is a Foxboro I / A distributed control system (Distributed Control System (DCS)).
[0052]
This will now be described specifically with reference to FIG. This figure illustrates a flow control system using sodium hydroxide where the alkali metal sulfamate formed is sodium sulfamate. However, the system is applicable to the use of other alkali metal sulfamate salts formed using water soluble bases other than sodium hydroxide. The basis of the control of the process of FIG. 2 is a nested cascade ratio flow control system used to simultaneously control the chlorine flow to the desired bromine flow set ratio. The combined total bromine / chlorine flow rate is then used to simultaneously control the flow rate of sodium sulfamate at the desired ratio of bromine / chlorine flow rate.
[0053]
One of the vessels shown is used to neutralize sulfamic acid to form sodium sulfamate. The desired water fill is added to these containers. The solid sulfamic acid is filled from individual bags or supersacks into the same container with stirring to form an aqueous sulfamic acid slurry. A 25% aqueous solution of caustic (NaOH) is fed to the sulfamic acid solution to form an aqueous sodium sulfamate solution. Next, the sodium sulfamate solution is moved by pump pressure to a second illustrated container with a pump in the circulation loop. The feed stream from the circulation loop is used to supply sodium sulfamate to the remaining continuous part of the process.
[0054]
Liquid bromine is continuously supplied from a pressurized bromine supply container. Bromine (primary stream) flows through a Micro Motion mass flow meter and then through an automatic control valve. The desired bromine flow is input as a set point to a bromine flow controller (master controller). The flow controller then signals the bromine control valve to change the flow to maintain the desired flow. A one-way check valve will be installed downstream of the bromine control valve to prevent backflow into the bromine supply line.
[0055]
Liquid chlorine is continuously supplied from a bulk supply vessel, augmented by the vapor pressure of the tank or by the nitrogen pressure. Chlorine (secondary flow) flows through a Micro Motion mass flow meter and then through an automatic control valve. The flow signal from the primary bromine mass flow meter / transmitter is sent to the chlorine ratio flow controller as a remote set point. Next, the chlorine ratio flow controller sends a signal to the chlorine control valve to change the chlorine flow as the bromine flow ratio. Install a one-way check valve downstream of the chlorine control valve to prevent backflow into the chlorine supply line.
[0056]
The bromine and chlorine lines are generally available from Koch Engineering Company, Inc. , P. O. Supplied together in a multi-element static mixer, available from Box 8127, Sichita, KS 67208. Static mixers work with minimal linear space and provide dynamic in-line mixing with no moving parts.
[0057]
The flow signals from both the bromine and chlorine mass flow meters / transmitters are output to a computer control system and integrated to obtain the overall flow of both streams. The overall flow value is then sent to a second ratio flow controller as a remote set point for the sodium sulfamate flow. A stream of sodium sulfamate is supplied onto the second illustrated vessel from pump pressure from a pump on the circulation loop. This stream flows through a Micro Motion mass flow meter and then through an automatic control valve. The flow signal from the sodium sulfamate mass flow meter / transmitter is sent to the ratio controller, which signals the control valve to change the sodium sulfamate flow as a combined bromine / chlorine flow ratio. Install a one-way check valve downstream of the sodium sulfamate control valve to prevent backflow of sodium sulfamate into the supply line.
[0058]
The sodium sulfamate stream and combined bromine / chlorine stream exiting the first static mixer are fed together into a second multi-element static mixer. The stream leaving the static mixer is the desired thickened liquid disinfectant composition, which is sent to a bulk product storage tank.
[0059]
An advantage of the flow system of the process of FIG. 2 is that the preparation of the sodium sulfamate solution can be performed outside the continuous part of the process. Large volumes of the solution can be prepared in advance and transferred to a sodium sulfamate feed vessel as needed to charge the water, mold and sulfamic acid as a normal batch operation. Further, the entire process can be controlled by entering a single set point for the desired bromine flow rate. All other material flow rates are obtained as internal remote set points. It should be noted that the magnitude of the desired flow ratio for the ratio controller is specifically formed within each controller as a set parameter for the set point value entered by the user.
[0060]
Now consider the process flow and control system of FIG. As in the case of FIG. 2, FIG. 3 is described with reference to a flow control system in which the alkali metal sulfamate is sodium sulfamate. However, the system is applicable to the use of any water-soluble alkali metal sulfamate formed using other water-soluble alkali metal bases.
[0061]
The process of FIG. 3 excludes the second container shown in FIG. 2, the container used in FIG. 2 as the sodium sulfamate supply container. The overall system of FIG. 3 includes additional control elements for the single vessel of FIG. 3 to continuously neutralize sulfamic acid and supply sodium sulfamate solution to the process. The continuous mixing process for supplying bromine, chlorine and sodium sulfamate is similar to that in FIG.
[0062]
In the process of FIG. 3, a 25% aqueous solution of caustic is supplied to the illustrated reaction vessel through a Micro Motion mass meter and then through an automatic control valve. The desired flow rate set point for the case body is input to the case body flow control device. The caustic flow controller then signals the control valve to change the caustic flow appropriately to maintain the desired flow. The flow signal from the cascading mass flow meter / transmitter is also sent to the water rate flow controller as a remote set point.
[0063]
Water is supplied to the illustrated reaction vessel through a Micro Motion mass meter and then through an automatic control valve. Next, the water ratio controller sends a signal to the control valve to change the water flow rate as a ratio of the caustic body flow rate.
[0064]
Solid sulfamic acid is filled into the illustrated container at a flow rate consistent with the water / caustic flow rate to provide the required sulfamic / sodium sulfamate concentration in the container. Specifically, a Rotolock valve is installed on the solids filling line to achieve solids supply at a set flow rate. This type of valve is a multi-blade rotary valve connected to a direct current (DC) motor with a flow controller. The speed of the motor is adjusted to provide the desired solids feed flow rate (determined from a separate calibration for speed versus flow rate). The Rotolock system can be further enhanced by installing equipment for automatic feedback control. This is usually accomplished by installing a solids hopper that feeds a Rotlock valve on the weighing cell. For this installation, the desired solids supply flow rate is input into the feed control unit. The controller signals the motor to increase or decrease the speed to achieve the desired flow rate. The solids flow rate is obtained from an internal calculation of the weight lost from the solids hopper over time. If the sulfamic acid filling system was equipped with an instrument for automatic control, the logical extension would be to send a solids flow signal to the case body flow controller as a remote set point for the desired case body flow. That would be. Since this step consists of a neutralization reaction, some residence time is required for complete neutralization to sodium sulfamate. Useful information indicates that neutralization is a mass transfer that is constrained by the feed rate of the caustic and also the cooling capacity of the reaction vessel. This neutralization is slightly exothermic and requires cooling to remove the heat generated. A pump on the circulation loop is one way to provide sufficient residence time if the flow rate of sodium sulfamate required for the remaining steps is not too high.
[0065]
Next, bromine, chlorine and sodium sulfamate are fed as in the process of FIG. Sodium sulfamate is fed continuously by taking the feed stream from a pump on the circulation loop from the illustrated reaction vessel and flowing through a mass flow meter and control valve. The desired flow is obtained from the sum of the total bromine / chlorine feed flows as a remote set point for the ratio flow controller.
[0066]
An advantage to the process of FIG. 3 is the elimination of one process vessel. This exclusion is compensated, at least in part, by the cost of the additional control elements required to supply water, cassia and sulfamic acid.
[0067]
It will now be appreciated and appreciated that the automatic flow control system described herein can be used to advantage in process layouts other than those illustrated in FIGS. An example of such another process layout is illustrated in FIG.
[0068]
The following claims, in accordance with the present specification, may refer to substances, components and / or components in their present forms ("comprising" or "being"), but not to one or more of them. Was first contacted with other substances, components and / or components and was present immediately before being blended or mixed, or, if formed in solution, present if not formed in solution. All possible substances, components or components are meant. When practiced in accordance with the present specification, the substance, component or component may have lost its initial identity due to a chemical reaction or conversion during the process of contacting, blending, mixing, or forming in situ. That is not important.
[0069]
The present invention is subject to significant changes in its implementation. Therefore, the above description is not intended to be limiting and should not be construed as limiting the invention to the specific examples presented above. Rather, what is intended to be covered is set forth in the following claims.
[Brief description of the drawings]
FIG.
FIG. 2 is a flow chart of a scheme of a plant arrangement suitable for performing the continuous process of the present invention.
FIG. 2
FIG. 3 is a flow diagram of a scheme of a plant arrangement of the present invention that includes an automatic flow control system.
FIG. 3
FIG. 3 is a flow diagram of another plant layout scheme of the present invention that includes an automatic flow control system.

Claims (39)

A method for producing a concentrated liquid sterilizing composition,
A) Nitrogen activity from an aqueous solution of (i) bromine chloride and (ii) an alkali metal salt of sulfamic acid having an active bromine content of at least 100,000 ppm (w / w) and greater than 0.93: 1 Continuously feeding the proportions of (i) and (ii) into the mixing device to produce an aqueous product having an atomic ratio of bromine, and B) maintaining a continuous feed in A). Withdrawing the product from the mixing device at a flow rate sufficient to be able to do so;
A method comprising: The method of claim 1, further comprising continuously forming said bromine chloride from bromine and chlorine. The bromine chloride continuously contacts bromine and chlorine in a vessel such that bromine chloride is produced, and a stream of bromine chloride product is continuously discharged from the vessel at a rate that maintains the supply of i) of A). 3. A process according to claim 2, wherein the stream is formed continuously by withdrawing at least a portion of the bromine chloride product stream, wherein at least a portion of the bromine chloride product stream comprises the bromine chloride stream of A) (i). The bromine chloride is continuously but from at least one of the at least two reaction vessels, and then alternately from at least one other, at a flow rate that maintains the flow of A) (ii). Formed continuously by withdrawing an aqueous solution of an alkali metal salt of sulfamic acid, during which time the solution is withdrawn from said at least one of the at least two reaction vessels, at which time the solution is withdrawn 3. The method of claim 2, wherein at least two of the at least two reaction vessels form a further aqueous solution of an alkali metal salt of sulfamic acid in said at least one other. Bromine and chlorine are continuously contacted in a vessel such that bromine chloride is produced, and a stream of bromine chloride product is continuously drawn from the vessel at a flow rate that maintains the supply of (i) of A). (Wherein at least a part of the bromine chloride product stream comprises the bromine chloride stream of (i) of A), and continuously but from at least one of the at least two reaction vessels, The bromine chloride is then formed continuously by drawing an aqueous solution of the alkali metal salt of sulfamic acid, at a flow rate that maintains the flow of (ii) in A), and then alternately from at least one other, and the bromine chloride is formed continuously. During the period, the solution is withdrawn from at least one reaction vessel, at which time a further aqueous solution of an alkali metal salt of sulfamic acid is formed in at least one other of the reaction vessels from which the solution has not been withdrawn. And which method of claim 2, wherein. The method according to any of the preceding claims, wherein (ii) of A) is an aqueous solution of the sodium salt of sulfamic acid and the atomic ratio is at least 1: 1. The active bromine content is in the range of 120,000 ppm (weight / weight) to 180,000 ppm (weight / weight), and the atomic ratio is in the range of 1.0: 1 to 1.4: 1; The method according to claim 1. The method according to any of the preceding claims, wherein the mixing device comprises a static mixer. The method according to any of the preceding claims, wherein the mixing device comprises a container with a mechanical stirrer. The method according to any of the preceding claims, wherein the product is withdrawn from the container intermittently. The method according to any of the preceding claims, wherein the product is continuously withdrawn from the vessel. The method according to claim 4 or 5, wherein the mixing device comprises a static mixer and the further aqueous solution of an alkali metal salt of sulfamic acid is formed from an alkali metal base, sulfamic acid and water. The mixing device comprises a static mixer, the aqueous solution of the alkali metal salt of sulfamic acid is an aqueous solution of sodium sulfamate, and the further aqueous solution of the alkali metal salt of sulfamic acid is a water-soluble sodium base, sulfamine. The method according to claim 4 or 5, wherein the method is formed from an acid and water. The sodium base is an aqueous sodium hydroxide solution and the sodium sulfamate is (i) an aqueous sodium hydroxide solution, and (ii) a slurry of sulfamic acid in water, or (iii) a separate charge of sulfamic acid and water; or 14. The method of claim 13, wherein (iv) both (ii) and (iii) are formed as an aqueous solution by charging a reaction vessel. A method for producing a concentrated liquid sterilizing composition, comprising:
a) Continuously forming bromine chloride from separate feed streams of bromine and chlorine by maintaining said stream under automatic feed flow control where the stream is continuously proportionedly mixed to form bromine chloride. thing,
b) The feed stream has an active bromine content of at least 100,000 ppm (w / w), a pH of at least 7, and a nitrogen to active bromine from (i) and (ii) above 0.93: 1. Under automatic feed flow control, which is continuously proportionally mixed in an amount to produce an aqueous product having an atomic ratio, (i) the aqueous solution of bromine chloride formed in a) and (ii) the alkali metal salt of sulfamic acid By continuously feeding separate feed streams into the mixing device, an active bromine content of at least 100,000 ppm (w / w), a pH of at least 7, and a nitrogen to active bromine over 0.93: 1 The aqueous product having an atomic ratio, and c) the aqueous product from the mixing device at a flow rate sufficient to maintain a continuous feed in a) and b). Be drawn Narubutsu,
A method comprising: 16. The method of claim 15, wherein the automatic feed flow control devices in a) and b) are under nested cascade ratio flow control. 16. The method of claim 15, wherein the temperature of the aqueous product formed in b) is controlled so as not to exceed about 50C. 18. The method of claim 17, wherein said temperature is maintained at about 30 <0> C. 19. The method of claim 17 or 18, wherein the temperature control is achieved by passing the effluent from the mixing device through a proximally located heat exchanger to remove excess heat from the effluent. 19. The method according to claim 17 or 18, wherein the temperature control is achieved by pre-cooling the aqueous alkali metal sulfamate solution before it reaches the mixing device. 16. The method of claim 15, wherein (ii) of b) is an aqueous solution of a sodium salt of sulfamic acid, wherein said atomic ratio is at least 1: 1. The active bromine content is in the range of 120,000 ppm (weight / weight) to 180,000 ppm (weight / weight), and the atomic ratio is in the range of 1.0: 1 to 1.4: 1. Item 22. The method according to Item 21. the automatic feed flow control device in a) and b) is under nested cascade ratio flow control, the temperature of the aqueous product formed in b) is controlled not to exceed about 50 ° C., and the mixing device 23. The method of claim 221, wherein said comprises a static mixer. said automatic feed flow control device in a) and b) is under nested cascade ratio flow control and the temperature of the aqueous product formed in b) is controlled not to exceed about 50 ° C; 23. A method according to claim 21 or claim 22, wherein the mixing device comprises a container with a mechanical stirrer. 16. The method of claim 15, further comprising producing at least an aqueous solution of an alkali metal salt of sulfamic acid in an amount sufficient to maintain a continuous supply of b) (ii). B) continuously, but alternately from at least one of the at least two reaction vessels, and then at least from the other one, at a flow rate which maintains the continuous feed of b) (ii) Withdrawing the aqueous salt solution and withdrawing the solution from at least one of the at least two of these reaction vessels during at least a portion of the period, at which time the solution is not withdrawn 16. The process according to claim 15, wherein a further aqueous solution of an alkali metal salt of sulfamic acid is formed in at least one other of the reaction vessels. 27. The method of claim 26, wherein (ii) of b) is an aqueous solution of a sodium salt of sulfamic acid, wherein the atomic ratio is at least 1: 1. The active bromine content is in the range of 120,000 ppm (weight / weight) to 180,000 ppm (weight / weight), and the atomic ratio is in the range of 1.0: 1 to 1.4: 1. Item 28. The method according to Item 27. the automatic feed flow controllers in a) and b) are under nested cascade ratio flow control, the temperature of the aqueous product formed in b) is controlled not to exceed about 50 ° C., and 29. The method of claim 27 or claim 28, wherein the mixing device comprises a static mixer. the automatic feed flow control device in a) and b) is under nested cascade ratio flow control and the temperature of the aqueous product formed in b) is controlled so as not to exceed about 50 ° C; 29. The method according to claim 27 or 28, wherein the mixing device comprises a container with a mechanical stirrer. Continuously withdrawing an aqueous solution of the alkali metal salt of sulfamic acid from the circulating inventory of the alkali metal salt of sulfamic acid (where the withdrawal is at a flow rate that maintains the continuous flow of (ii) of b); And the aqueous solution of the alkali metal salt of sulfamic acid from the reaction vessel is produced, at least periodically, in an amount sufficient to at least maintain their circulating inventory. 17. The method of claim 15, further comprising continuously replenishing a circulating inventory from the feed. 32. The method of claim 31, wherein (ii) of b) is an aqueous solution of a sodium salt of sulfamic acid, wherein said atomic ratio is at least 1: 1. The active bromine content is in the range of 120,000 ppm (weight / weight) to 180,000 ppm (weight / weight), and the atomic ratio is in the range of 1.0: 1 to 1.4: 1. Item 33. The method according to Item 32. the automatic feed flow control device in a) and b) is under nested cascade ratio flow control and the temperature of the aqueous product formed in b) is controlled so as not to exceed about 50 ° C; 34. The method of claim 32 or claim 33, wherein said mixing device comprises a static mixer. the automatic feed flow control device in a) and b) is under nested cascade ratio flow control, the temperature of the aqueous product formed in b) is controlled not to exceed about 50 ° C., and 34. The method of claim 32 or claim 33, wherein the mixing device comprises a container with a mechanical stirrer. 26. The method of claim 25, wherein said aqueous solution of an alkali metal salt of sulfamic acid is formed from a water-soluble sodium base, sulfamic acid and water. 16. The method of claim 15, wherein said pH is in the range of 13.0 to 13.7. 24. The method of claim 23, wherein said pH is in the range of 13.0 to 13.7. 25. The method of claim 24, wherein said pH is in the range of 13.0 to 13.7.

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