MXPA99001434A - Method and apparatus for high efficiency reverse osmosis operation - Google Patents

Abstract

A process for treatment of water via membrane separation to remove hardness and non-hydroxide alkalinity by simultaneous removal in a weak acid cation exchange resin. The process includes ionization of sparingly ionizable components, such as silica, by adjusting the pH up to about 10.5 or higher. Their separation by the membrane is significantly increased. The passage of boron, silica and TOC is reduced by a factor of ten or more. Recovery of 90%or higher is achievable with most brackish feedwaters, while substantial reduction in cleaning frequency is simultaneously achieved. The apparatus used for the water treatment process includes reverse osmosis membrane(s) (30), mixed bed ion exchange unit (44, 46), micron filter (48), ultraviolet sterilization unit (49), decarbonation unit (20), and electrodeionization unit (150).

Description

>; «** METHOD AND DEVICE FOR THE OPERATION OF REVERSE OSMOSIS HIGH EFFICIENCY Field of the Invention My invention relates to a method for treating water in membrane-based water treatment, purification and concentration systems, and to the apparatus for developing the method. In one embodiment, my invention relates to the methods for the pre-treatment of the feed water and for the operation of reverse osmosis equipment 10 ("Oi"), which achieves an increased rejection of solute, thus producing a product water of very high purity (low content of solutes), at the time when there is a significant increase in the availability in the current of the water treatment equipment.

Background of the Invention There is a continuous demand for a simple, efficient and economical process that can reliably provide water of a desired purity, in equipment that requires a minimum of maintenance. In particular, it would be desirable to improve the efficiency of the use of feedwater, and reduce both the operating costs and the capital costs of high purity water systems, as required by various industries, to know, semiconductor, pharmaceutical, biotechnology, thermoelectric plants and nuclear power plants. In most water treatment systems for the aforementioned industries, the design of the plant and the operating parameters are generally linked to the final concentrations (usually expressed as the total dissolved solids, or "STD"), which are tolerable in the selected equipment with respect to the solubility limits of the species presently sparingly soluble. In particular, silica, calcium sulfate and barium sulfate often limit the final concentrations that can be achieved. In many cases, including the operations of several nuclear plants and water purification plants, boron and other ampholytes of similar action present a relatively high rejection through the membranes in the conventional operation Oi systems, and can govern the design and operational limits. More commonly, the presence of said compounds results in water so poor reverse osmosis product, known as an infiltrate, that an additional secondary treatment of Oi is necessary to produce water of acceptable purity. In any case, to avoid formation of scale and the resulting decreases in membrane performance, as well as potential harmful effects on the life of the membrane, the design and operation of a membrane-based water treatment plant must recognize the possibility of silica and other types of inlay formations, and should limit the proportions of water recovery and corresponding operating practices. In fact, the typical experience with Oí plants has shown that the decrease in the flow rates or deterioration of the quality of the infiltrate, or increases in the pressure drop in the membrane, require chemical cleaning of the membrane at regular intervals. This cleaning has historically been required due to the formation of scale on the membrane, contamination by particles or biological contamination, or some combination of these. Due to the cost, inconvenience and production losses that result from the membrane cleaning cycles, it would be advantageous to prolong as much as possible the time between the required chemical cleaning, while efficiently rejecting the undesirable ionic species and The production of high purity infiltrate is reliably achieved. Since the introduction and almost universal adoption of film or thin film composite membranes in the mid to late 80s, improvements in Oi technology have evolved in nature. The operating pressure required to achieve the desired rejection and flow (ratio of infiltrate production per unit of surface area of the membrane, commonly expressed as gallons per square foot of membrane per day, or liters per square meter per day), has been slowly reduced, while the average rejection of the thin film composite membrane has been increasingly improved. Historically, Oi systems for brackish water have been limited in their allowable recovery and flow rates due to the tendency to fouling and contamination of feedwater. It would be desirable to reduce the tendency for scaling and contamination of brackish water to a point where the limits of recovery are governed by osmotic pressure and where the flow rates can be substantially increased, compared to the limits of conventional OI systems. Brackish water. From the point of view of the typical end user, several areas of improvement in Oi technology are still sought (tolerance to chlorine is one of them). Membranes composed of thin layers or films are relatively more prone to biological and particulate contamination, due in part to their surface charge and characteristics. With certain feedwater, especially from surface water sources, the contamination of the membrane and the frequent cleaning required to combat it can represent arduous, costly and time-consuming operational challenges. It is known that the rejection of weakly ionized species, such as total organic carbon ("TOC"), silica, boron and the like, is significantly lower than the rejections of highly ionized species such as sodium, chlorine, etc. Since the ion exchange efficiency of the secondary IO is determined primarily by the level of the weak anions present in the Oi infiltrate, it would be advantageous to eliminate (reject) as many weak anions as possible in the operation of the Oi unit. In other words, by removing (rejecting) more silica (and boron) in the Oi stage, a greater performance in the operation of the ion exchange unit preceding the Oi unit can be achieved. With the exception of an OI process presented in Patent No. 4,574,049 of the USA, issued on March 4, 1986 to Pittner for a REVERSE OSMOSIS SYSTEM, which presents the design of a double-pass OI system (product in stages). ), carbon dioxide typically represents the largest fraction of the anion charge in the Oi infiltrate. However, a multiple-pass OI configuration provides very few benefits depending on the operating conditions of the conventional Oi system, since the carbon dioxide content of the infiltrate remains at the same (absolute) level and represents an even larger fraction of the load. of anions. The high rejection of weak anions in a single-pass OI system is therefore considered another area where a significant improvement is still sought. In addition to increasing the rejection of weakly ionized species, a greater rejection of highly ionized species is also desired.

The rate of recovery or volumetric efficiency is another parameter where improvements in the performance of the Oi system would represent an advantage. A typical Oí system operates at a recovery of approximately 75 percent, where only 75 percent of the incoming feed is used to the Oi, and the rest (25 percent) is discharged. Because water becomes increasingly scarce and expensive around the world, increasing the rate of maximum recovery achievable in an OI system is an important goal. Increasing the flow of operation is always significant for end users, since it reduces capital costs. End users also seek simplification and cost reduction for the secondary operations of the Oi unit. This is because the permissible levels of impurities in ultrapure water have continuously decreased with the strict design rules in the geometry of the semiconductor device. In this way, lower levels of contaminants are required in the ultrapure water system. As a consequence, the cost and complexity of the components of the secondary OI system have grown enormously in recent years. The high purity water process procedures and the hardware required to develop them are complex and expensive. In fact, the regenerable mixed bed ion exchange system represents by far the most expensive (and complicated) unit operation / process in the entire treatment system for ultrapure water. Thus, the significant improvement in the characteristics of the water treated by Oí would greatly reduce the overall cost and complexity of the system for ultrapure water. Several attempts were made, some in high purity water treatment applications and some in wastewater treatment applications in which an effort was made to improve the efficiency of the rejection of certain sparingly soluble ions in the aqueous solution at a neutral pH or almost neutral. These attempts were characterized mainly by conventional removal of the hardness and then elevation of the pH with the addition of chemicals. Such a method is shown in U.S. Patent No. 5,250,185, issued October 5, 1993 to Tao et al., For REDUCTION OF LIQUID BORO CONCENTRATIONS WITH REVERSE OSMOSIS MEMBRANES OPERATING AT HIGH pH. In a preferred embodiment, its invention indicates the use of a conventional zeolite softener followed by a weak acid cation ion exchanger operated in sodium form to eliminate divalent cations. Due to the limitations of the equipment and the design of the process, the steps of the pre-treatment involve a rather expensive and somewhat undesirable step of dosing the feed water with an scale inhibitor to further prevent hardness incrustations. In addition, although its method does provide a stage of simultaneous removal of hardness and alkalinity, which is beneficial in many types of applications that interest me, its method does not provide high efficiency at that stage of removal, as evidenced by the fact that two additional smoothing steps downstream are required in your process. Additionally, its application belongs, and is described and claimed in relation to oil field waters containing hydrocarbon compounds (they contain only carbon and hydrogen, and generally can not be ionized), while in the applications that concern me, said compounds are Absent almost completely. In applications of my primary interest, a variety of natural organic acid, such as humic and fulvic acids, is present. especially in surface water subjected to treatment. In addition, a method used in high purity water applications was presented in Japanese Kokai No. Sho 58-112890, published on June 29, 1984 by Yokoyama et al., For a METAL DEALINEATION WITH REVERSE OSMOSIS MEMBRANE UNIT. Their examples present reverse osmosis units that use a pre-treatment process with strong acid cation exchange resin ("SAC") to soften in one example, and without softening in the other example. Although its process will work for certain feed waters, it does not indicate how the operation can be employed at higher pH levels, at the same time as the fouling of the Oi membranes is avoided. In order to better understand my process, it is useful to know some basic principles of water chemistry. With respect to calcium carbonate (CaCO3), for example, the probability of precipitation occurring in an Oi membrane in the final rejection zone can be predicted using a Langelier index, sometimes known as the Langelier Saturation Index (LSI). See Nalco Water Manual, 1979 rights, by McGraw Hill. The index is formulated as follows: LSI - pHrec | -azo - pHs where pHs = the pH at the time of saturation of CaCÜ3 (rejection) and pHs = pCa + pAlk + C and where: pCa = -log of the concentration of the ion Ca "* - 1" ( moles / liter) pAlk = -log concentration of the HCO3 ion "(moles / liter) C = a constant based on the total ionic strength and the rejection temperature of the Oi.

In a reject water of Oi, in order to avoid carbon fouling, it is preferable to maintain the negative LSI, that is, in a condition in which the CaCÜ3 can dissolve. However, in the field it has been found that under certain conditions, with the use of certain types of anti-fouling additives, an LSI of up to about +1.5 can be tolerated, without CaC03 inlays. In any case, at the pH of any given rejection of Oi, the pH should be minimized in order to avoid undesirable formation of scale. To put this in perspective, consider that in any pre-treatment operation by Oi, it can be anticipated that there will always be at least some calcium leakage from the smoothing stage. Thus, depending on the hardness of the raw feed water and the pre-treatment process, a lower limit can be expected in the value obtained from the pCa term, due to the concentration of the Ca ion ** present in the treated feed water. I heard In this way, in any case the value of C is given by the total ion strength or intensity and by the temperature. Thus, in order to maintain the LSI in an acceptable range, in order to facilitate an Oi operation free of scale, calcium leakage (as well as other hardness such as magnesium) becomes a critical value. The Tao et al. Patent, described above, addresses this problem by providing various types of series softeners. In particular, it inevitably accepts the capital and high operating costs associated with this problem. On the other hand, Yokoyama decides to limit the Oi operation to a pH that is consistent with the degree of calcium removal. When operating with a rejection of Oi at pH of 9, assuming a leak of 0.1 ppm of C ** from the presented ion exchange sequence, and a concentration factor of 5 ("5X") in the Oi, it can be expected have your Oi operation provide a rejection with an LSI of approximately -0.5. Said LSI is acceptable for an operation without inlays, with or without scale inhibitors. However, if the pH of the Yokoyama example were to increase to l l, for example, given the pretreatment method, an LSI of about +2.4 could be expected. In such a case, the Langelier Saturation Index of the reject water would be well above the level at which the current anti-foulants have the ability to provide an Oi operation without inlays. Thus, for the most part, the above technical methods have one or more of the following deficiencies for me: (a) they do not reliably achieve the extremely low levels of hardness and alkalinity without hydroxide, necessary for an operation free of scale at levels of very high pH; (b) are based on redundant and expensive equipment with operating costs of a technical guard operator to reduce the minimum leakage of hardness, (c) depend mainly on the reduction of the hardness to lower the LSI of the rejection of the Oi ( and do not include methods for high efficiency dealkalization), and (d) rely on additives against scale to prevent their formation. In this way, the advantages of my simple treatment process are important and obvious, and promote (a) removal of hardness at very low residual levels, and (b) efficient dealkalization to provide a long Oi operation without problems at levels of high pH Likewise, due to the upper limits, of the concentration factor due to the tendency to form scale, the Oi systems often can not take advantage of about twenty five percent (25%) or more of the raw feed water. In addition, at recovery levels greater than seventy-five percent (75%) or slightly lower, depending on the chemistry of the raw water, the control of biological contamination and fouling by chemicals in conventional Oi systems becomes increasingly difficult to carry out when trying to achieve long runs. Therefore, the widespread commercial use of Oi systems with water recovery of more than seventy-five percent (75%) has not yet been achieved. Because water is increasingly expensive, or scarce, or both, it would be desirable to increase the ratio between the treated product water and the raw water feed in the Oi systems. Therefore, it can be seen that it is advisable to achieve lower costs for water treatment, allowing it to be carried out at the proportions of total recovery commonly obtained today. Finally, it would also be desirable to comply with increasingly demanding water treatment objectives, with a better availability of the system and with longer runs than those currently achievable. So far, to this date nobody has thought it feasible to operate a reverse osmosis water treatment system at a pH higher than 9 in continuous, sustainable and long-term operations to produce extremely purified treated water. The conventional engineering approach has been to design a way to avoid or combat the formation of scale, using a moderate pH, limiting the final concentration and the recovery of the resulting water, through the use of chemical additives. Historically, cellulose acetate membranes are limited in operation to a pH range of just 4 to 7. The newer membranes, polyamide and thin-film type, have been traditionally operated within a pH range of just 4 to 8. Although sometimes the operation with higher pH has been tried for some special purposes, it has usually been in applications without silica. In addition, although the operation with higher pH has been used in second stage OI applications where silica was a concern, it was only achieved after a first step OI operation with a neutral or near neutral operating pH. . In cases where organics are a problem, the pH can often vary from less than 5, or preferably to less than 4. In contrast to previous technical methods for water treatment, the method presented here employs a philosophy of Essential design to eliminate practically all the possibility of scaling during a first pass operation at a maximum achievable pH using the available membranes, while retaining the desired concentration factor, and taking advantage of the resulting water recovery benefit.

Compendium I have invented a new method of water treatment based on the elimination of aggressive hardness and alkalinity, followed by membrane separation at high pH, to produce a high quality infiltrate with extremely low concentration of silica. In a single feedwater treatment process, raw feedwater of suitable chemical composition is treated with a weak acid cation ion exchange resin, operated in the form of hydrogen, to simultaneously remove the hardness and alkalinity. The weak acid cation ion exchange resins can be operated at initial levels of hardness and alkalinity of the raw feed water well above the levels that would cause conventional ion exchange systems to fail due to hardness interference. The design of the preferred treatment used in my wastewater treatment plant overcomes a number of important and serious problems. First, low hardness, combined with the almost total removal of the alkalinity without hydroxide, substantially eliminates the precipitation of the scale forming compounds associated with the sulfate, carbonate and silicate anions. Therefore, the cleaning requirements are minimized. This is commercially important since it allows a water treatment plant to avoid the loss of water production that would otherwise require an undesirably larger size of the treatment plant in order to be able to reconcile the production lost during the cleaning cycles. Second, the preferred high pH operating conditions allow a high degree of ionization that can be achieved in various sparingly ionized species at a neutral or near neutral pH in aqueous solution, to allow said species to be rejected preferably by the membrane system. Finally, the operation at high pH provides protection against biological contamination, thus avoiding undesirable contamination of product water. At the preferred high operative pH, the bacteria and endotoxins are efficiently destroyed. In essence, water treatment systems operated in accordance with the concepts contained herein, operate normally under conditions that could be considered as clean-up for conventional Oi systems. I have developed an innovative process design for use in water treatment. In one embodiment, the process includes the treatment of a feedwater stream that is characterized by the presence of (i) hardness, (ii) alkalinity, and (iii) molecular species that are poorly ionized when found in aqueous solutions of Neutral or almost neutral pH, to produce a product stream with low solute content and a reject stream with high solute content. The process has to do with the effective elimination of the tendency to form encrustations of the feed water when the raw feed water has the desired concentration factor at the selected pH, carrying out, in any order, one or more of the following steps , (i) remove hardness from the raw feedwater stream, (ii) remove the alkalinity from the raw feedwater stream, or (iii) remove the dissolved gases created during the hardness removal step. Thus, the pH of the feed water rises to the selected pH of at least about 8.5, or up to 9.0, or up to 10, or preferably (with the thin film composite membranes currently available) at a range between 10 and 1 1 , or of another form, of more than 11, and preferably around 12 or a little more, until the benefits obtained by the high proportions of rejection of silica and other species, justify the additional cost. With thin film membranes currently available, pH control to or around 10.5 provides the greatest benefits of this method, without compromising long-term membrane life. The pH increase is achieved by adding a selected base to the softened and dealkalized feed stream, preferably by direct injection or by using an ion exchange of anion. The increase of the pH drives the barely ionized molecular species when they are in neutral or almost neutral pH, towards an increased ionization. An optional concept is that substances that accept protons, or bases, are increased. The pH-adjusted feedwater is then sent through a membrane separation equipment, typically of the reverse osmosis type, but alternatively of nanofiltration or another suitable type or configuration that is currently available or in the future, and where You can apply this method to produce a reject current and a product stream. It is ideal membrane separation equipment that has a semi-permeable membrane that substantially resists the passage of ionized species. It is important to note that in my process, the membrane separation equipment produces a product stream that is almost free of the species that are usually avoided and that are barely ionized when they are in aqueous solutions of neutral or almost neutral pH .

OBJECTIVES, ADVANTAGES AND CHARACTERISTICS OF THE INVENTION From the foregoing, it is evident that an important and primary objective of the present invention resides in providing an innovative method to treat water to produce, continuously and reliably in long operating cycles, a current product of Water of pre-selected quality of very high purity. More specifically, an important objective of my invention is to provide a membrane-based water treatment method which is capable of avoiding the common problems of scale formation and contamination, so that a reliable method of generating high water is constituted. purity when operating at high efficiency. Other important yet more specific objectives of this invention reside in providing a method for treating water as described in the previous paragraph, which: • allows the removal of hardness and alkalinity of a selected feedwater to be carried out in a simple and direct • have a minimum of process requirements; reduce and avoid complex chemical dosing systems; • requires less physical space than existing technology water treatment plants; • be easy to build, start and service; • have high yield rates, that is, that provide high product water discharges, relative to the amount of feed water supply to the water treatment plant; • jointly with the previous objective, provide unit costs to the operator of the water treatment plant and therefore to the end user, less than the current ones; • in conjunction with the previous objective, resulting in less chemical consumption than most water treatment facilities, practically eliminating the use of some chemical additives commonly used for this purpose, especially scale inhibitors.

A feature of one embodiment of the present invention is the use of a unique combination of weak acid cation ion exchange with an almost total removal of hardness and alkalinity, and a subsequent operation of Oi with high pH, thus allowing the plant of water treatment reduce the percentage of reject water to a minimum. This results in high efficiencies of the global cycle. Another characteristic of the present invention is the use of a high pH operation for a high ionization of barely ionizable species such as silica, boron and TOC, thus allowing an operation with silica, boron and TOC rejection levels that far exceed the limits of traditional treatment systems by Oi when it comes to feeding water of a comparable chemistry. A further feature of the present invention is the ability to retrofit existing Oi plants to function in accordance with the design of this process, and to increase their capacity without increasing Oi membrane requirements. Another feature of the present invention is the ability to provide product water of higher purity while operating at higher flow levels than those feasible with conventional Oi system designs. Other important and additional objects, features and advantages of my invention will become more apparent to those having knowledge of the technology in question, and from the following detailed description, and appended claims, together with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings, identical features shown in several figures will be referred to by identical reference numbers without further mention. Figure 1 illustrates the percentage ionization of silica ions in aqueous solution as a function of pH. Figure 2 illustrates a first embodiment of my method for a high efficiency reverse osmosis operation, showing the use of a weak acid cation exchange unit for the simultaneous removal of hardness and alkalinity without hydroxide. Figure 3 shows a second modality of my method for a high efficiency reverse osmosis operation, where the hardness is reduced by softening by sodium zeolite and optional softening with lime or lime / soda.

Figure 4 shows a third modality of my method for a high efficiency reverse osmosis operation, where the configuration of the equipment is represented that the alkalinity in the raw feed water can be efficiently and suitably reduced by addition of acid, and where the Hardness can be reduced optionally with softening with lime or lime / soda. Figure 5 illustrates the differential pressure, in pounds per square inch, versus time (PSID vs. Months) for the reverse osmosis membrane used in reverse osmosis test pilot equipment, using my innovative process. Figure 6 illustrates the normalized flow of the infiltrate in liters per minute versus time, for the reverse osmosis membrane used in the reverse osmosis test pilot using my innovative process. Figure 7 illustrates the concentration of silica in the reverse osmosis reject stream in a reverse osmosis test pilot using my innovative process. Figure 8 illustrates the percentage of silica rejection versus time, for a reverse osmosis membrane used in the pilot of my innovative process. Figure 9 describes the use of my Oi system operation method when a multi-pass process is used to sequentially process a portion of the initial feedwater and produce an infiltrate that has passed through more than one OI membrane. . Figure 10 illustrates the use of my OI system operating method for boiler fill / fill water, or for complement / fill water for cooling tower, or for add-on water / scrubber fill. Figure 11 illustrates the use of my Oi operating method in combination with continuous electrodeionization equipment for high purity water production. Figure 12 illustrates a process flow diagram for a configuration of my Oi system process design. Figure 13 illustrates a scheme of the system for a conventional process design of the Oi system. Figure 14 illustrates a process flow diagram of my high efficiency Oi method, using the design and operation concepts mentioned here.

Detailed Description of the Preferred Modes of the Invention I have developed a new method for the design of the process and operation of the Oi systems. This new method for designing the process and operation of the Oi systems has been widely tested. The process has shown that it is capable of achieving significant improvements in the OI's operating objectives. The attributes that characterize my process design and operation of Oí brand HERO (MR) include: (1) Very high rejection of all contaminants, especially weak acid anions, such as TOC, silica, boron, etc. (2) Recovery with high reliability index. A recovery of ninety percent (90%) or more can be achieved. (3) Biological contamination is practically eliminated. (4) Particle pollution is substantially reduced. (5) The frequency of cleaning is significantly reduced. (6) Removal of chlorine from feedwater may not be required, due to the resulting chemical species present in the high pH of operation or, in some cases, eliminating the need to add chlorine in the first place. (7) Addition of scale inhibitors is almost completely eliminated. (8) A substantially higher flow is achieved. (9) Reduced total capital cost, compared to conventional Oi systems. (10) Reduced total cost of operation, compared to "conventional OI systems." (11) The complexity of an ultrapure water system is significantly eliminated.The OERO brand HERO system is site specific. The process is customized to suit the specific feed water of a site, regardless of the difference in the pre-treatment process for the different sites, the Oi system mainly operates at the highest reject pH possible, consistent with the highest limit of Permissible pH for currently available OI membranes (for example, pH 11.0 for FILMTEC® Oi elements), a typical HERO brand OI system is designed to operate at a pH of up to about 1 1, when measured in the Oi reject current. Due to the very high concentration factors (ie the percentage recovery) allowed by my OI brand HERO process, the OI feed pH is very low. For example, in a system that operates at ninety percent (90%) recovery, a feed pH of 10.0 will produce a rejection reaction at a pH of approximately 11, provided that the Oi feed is slightly regulated by the presence of carbonate, phosphate, etc. Unlike conventional Oi systems, normally operated at a recovery of around seventy-five percent (75%), a HERO-branded OI system can be operated on a routine basis to a recovery of ninety percent (90%) or more , limited only by the osmotic pressure of the rejection of the Oi. The increase of the pH from the feed of the Oi to be rejected, is extended to very high recoveries. Thus, the maximum permissible pH is applied specifically to the rejection conditions of the Oi. In order to operate an Oi system with rejection of up to a pH of 11, or around l 1, or greater, several process conditions must be met to effectively eliminate the potential for scale formation on the Oi membranes. Some of these process conditions are also necessary to operate an OI system at a very high rate of recovery. Said process conditions are the following: (1) The concentration of calcium, magnesium, strontium and barium in the Oi feed must be substantially eliminated, preferably almost to zero, and better still to zero. (2) The content of aluminum, iron and manganese, including organically bound species, as well as the presence of colloidal particles containing said materials, must be substantially eliminated and preferably to zero. (3) Regulatory anions, specifically bicarbonate, or carbonate and / or phosphate species, should be reduced to the lowest possible level. The selection of specific operations and control points to meet the indicated process conditions is influenced by the characteristics of each particular feedwater. The percent recovery needed (or desired for a specific application) also affects the operation and control point criteria. Figure 2 represents a very cost-effective process sequence of the Oi unit. The first step is to adjust the hardness-alkalinity ratio of the feedwater, if necessary. The optimization of this proportion, which is usually done by the addition of alkali, makes the complete removal of the hardness feasible in the next step of the process. The second step in the process sequence of the Oi includes the use of a weak acid cation resin (WAC), for example MAC-3 of DOMEX®, Lewatit CNP-80, Amberlite®, IRC-86). Operated in the form of hydrogen, the WAC resin removes the hardness quantitatively, given the adequate hardness-alkalinity ratio of the influent. The hydrogen ions released in the cation exchange process react with the alkalinity and produce carbonic acid (H2C03) 2, which dissolves in the WAC effluent. The third step includes adding acid to the WAC effluent to destroy the remaining alkalinity, if any. The total removal of alkalinity in this step is important to achieve a very high recovery throughout the Oi system. In a fourth step, the acidified effluent, which contains practically no hardness and alkalinity, is then treated for removal of the carbon dioxide. This removal can be achieved in a forced / induced draft decarboniser or in an existing vacuum degasser, either of packed bed design or gas permeable membrane barrier. Decarbonized water, with essentially zero hardness and alkalinity, it is then injected with a soluble alkali, preferably to adjust the pH to 10.0 or more, and better still at a pH of 1 1 or about 1.0 in the rejection of the Oi. The next step is to operate the Oi system in such a way that the rejection pH is approximately, but preferably not greater than, 11.0. Note that the limitation of this pH of 11 is simply applied in relation to the currently available Oi membranes. An exemplary membrane, with the greatest capacity for pH tolerance, is an FT30 membrane from FILMTEC. If Oi membranes with greater capacity for pH tolerance are available in the future, then the maximum permissible OI rejection pH, with the resulting benefits of the highest pH, of more than 1.0 can be increased accordingly.

Feeding waters used to produce high purity water, as well as those found in wastewater treatment, include the presence of silicon dioxide (also known as silica or Si02) in one form or another, depending on the pH and other species present in the water. For membrane separation systems, and in particular for membrane type Oi separation systems, the formation of scale of the membrane due to silica should be avoided at all costs. This is because (a) silica forms relatively hard incrustations that reduce membrane productivity, (b) it is usually difficult to remove, (c) the scale removal process produces undesirable amounts of spent cleaning chemicals, and (d) Cleaning cycles result in undesirable and unprofitable off-line periods for the equipment. Therefore, regardless of the level of silica in the raw feedwater at the inlet, the operation of conventional membrane separation processes usually includes Si02 concentrations in the stream of high total dissolved solids ("TDS") at a level that is not higher than 150 ppm of Si02 (as Si02). Normally, Oi systems are operated at reduced rates of recovery, when necessary, to prevent the concentration of silica in the reject stream far exceeding 150 ppm. The formation of scale due to various compounds that cause it, such as calcium sulfate, calcium carbonate and the like, can be predicted by people who are aware of this technology, and for which this specification is addressed, by using the index of Langlier saturation, as discussed above, or by other available solubility data. The operating parameters, including temperature, pH, infiltrate or reject flow rates, as well as the various species of ions in the raw feedwater, and the species that are added during the previous treatment should be appropriately considered. I have found that by adequately removing the hardness and alkalinity without hydroxide, at levels that effectively prevent scale formation at a pH selected for the Oi operation, the concentration of SiO2 in the OI reject stream can rise with Safety up to 450 ppm or more. This is achieved by increasing the pH of the feed water of the Oi system, and without using chemical scale inhibitors. Furthermore, even with this increase in silica in the Oi rejection, the level of silica contamination in the Oi infiltrate is preferably and substantially decreased, when compared to the silica that can be expected under conventional OI process conditions. . It is commonly known that the solubility of silica increases when the pH is increased, and that the silica is quite soluble in high pH aqueous solution. Along with the solubility, the degree of ionization of the silica also increases with an increased pH. While the increase in the solubility of silica is not directly proportional to the degree of ionization, the rate of increase in the solubility of silica is basically proportional to the rate of change in ionization. This discrepancy between solubility and ionization is explained by the fact that even undissociated silica has a certain solubility in aqueous solutions, usually around one hundred twenty (120) ppm and up to one hundred sixty (160) ppm, depending on the temperature and other factors. In comparison, the solubility of the silica at a pH of 1 1 is more than one thousand five hundred (1, 500) ppm at room temperature; the silica is increasingly soluble as the temperature and / or the pH increase. Silica is very weakly ionized when it is found in neutral or almost neutral aqueous solutions and is generally considered to exist as undissociated silicic acid (meta / ortho-) (H SiO) in most natural waters with a pH of up to 8. It is known that the value of the dissociation constant (pKa) for the first dissociation step of the silica is about 9.7, which indicates that the silica is ionized approximately fifty percent (50%) at a pH of 9.7; the other fifty percent remains as silicic acid (ortho) without dissociating at said pH. A graphical representation of the relationship between the pH and the percentage ionization of the silica is shown in Figure 1. It is obvious that it would be advantageous when silica ionization is desired to operate at a pH of more than 10, and more preferably more than 11, or even more preferably more than 12. The understanding of the ionization phenomenon of silica is important since the rejection of most of the species in all membranes of the membrane separation equipment is improved by increased ionization. Accordingly, it can be expected that the rejection of the silica by an Oi membrane will improve as the degree of ionization increases; With respect to silica, the ionization increases to a higher pH. Therefore, increasing the pH of the Oi operation provides superior benefits. First, the solubility of silica can be radically increased, even if it remains within the current pH limits of commercially available thin film composite Oi membranes. Second, the rejection of silica increases significantly at high pH levels, which correspond to a higher degree of silica ionization. To obtain a maximum benefit of the ionization of the silica at high pH, the system ofI heard it should be operated at a pH as high as possible, given the limitations imposed by the chemistry of the membrane and by the manufacturer's guarantee of the membrane. Preferably, the Oi system is operated at a pH of about 10, or above, and more preferably at 10.5 or more, and more preferably at a pH of 1 1 or more. This contrasts with the typical operation of the Oi, where the operating pH has been limited to around 8.5 in order to avoid the formation of scale, especially silica and carbonate incrustations. Referring again to Figure 2, a modality of my process for the operation of the membrane separation equipment is presented. In this method the raw water 10 is first treated in the weak acid cation ion exchange unit 12, where the hardness and bicarbonate alkalinity are simultaneously removed. For cases where the hardness of the raw water 10 is greater than the alkalinity, the operation of the weak acid cation ion exchange unit 12 must be facilitated by addition of an alkalinity source 13, such as with the addition of an aqueous solution of sodium carbonate (Na2C03). Preferably, the WAC unit 12 is operated in the hydrogen form to facilitate operation and regeneration. However, it would also work in the sodium form, followed by the addition of acid. In any case, in the mentioned case and optionally when appropriate, the acid 14 is added by a pump 16 to the effluent 18 from the WAC 12 unit (s) to improve the destruction of the bicarbonate. Then the carbon dioxide 19 that has been created in the WAC (and / or by addition of acid) is removed, preferably in an atmospheric or vacuum degasser 20. Finally, an alkali 22 (base) is added, preferably by injection by pump 24 of liquid solution, to increase the pH of the feed water 25 to a selected level. Any of the available and affordable basic products can be used, as long as there is no appreciable tendency to form scale. In addition to the use of common sodium hydroxide, other chemicals such as sodium carbonate, potassium hydroxide, or potassium carbonate could be selected. In fact, in certain cases, an organic base such as a pyridine-type compound can be used effectively to carry out this process. In any case, the pressurization of the feed water 25 for a membrane process is achieved by a high pressure pump 26 prior to transfer to the membrane separation unit 30 Oi type, as shown. Alternately, the addition of alkali (base) to the feed water can be carried out by passing the feed water through an ion exchange unit of anions 31 to increase the pH to a desired level. The pH of the feedwater is raised to a selected pH of at least about 8.5 or 9.0, or up to about 10, or preferably (with thin film composite membranes currently available) at a range between 10 and 11, or of more than 11, or better still of 12 or more, and more preferably of 13 or more. With the currently available Thin Film composite membranes, such as those sold by DOW CHEMICAL of Midland, Michigan, with its FILMTECH brand of its subsidiary FILMTEC, INC., PH control at around 10.5 provides the greatest benefits of this method. , without compromising the life of the membrane in the long term. However, to increase silica solubility and rejection thereof, membranes are recommended which allow the pH to rise to at least 1 1, or preferably to at least 12, or more preferably to at least 13. Thus, it can be appreciated that my method can be used with greater advantages when membranes with long life expectancies at said high pH are commercially available. The reject 32 of the membrane separation unit 30 may be sent to the drain or may be sent for subsequent treatment as required by the particular circumstances of the site. The infiltrate 34 of the membrane separation unit 30 can be used "as it comes" or can be further purified to eliminate residual contamination, for example, for users of high purity water, such as semiconductor manufacturers, where purity water of 18.2 mega ohm is desired. A conventional sequence of secondary treatment to Oi for production of high purity water 38 in the semiconductor industry includes a cation exchanger 40, followed by an anion exchanger 42, with primary mixed 44 and secondary mixed bed polisher ion units. 46. Some somewhat different after-treatment sequences can be used to meet the particular needs of a given site, raw water chemistry and end use, without departing from the advantages and benefits that can be obtained with the OI process method here. described. For example, it may be desirable in certain circumstances to omit the ion exchangers of cations 40 and anions 42, and derive the Oi infiltrate via line 47 to directly reach the primary mixed bed 44 ion exchange units, and mixed bed of Polishing 46. Finally, in many ultrapure water plants, the product of the mixed-bed polishing ion exchange units 46 is subsequently treated in final filtration units 48 and in ultraviolet radiation units 49 to eliminate particulate and biological contamination. , respectively. Additional treatment operations may be included as appropriate to meet a specific end user. Another unique and distinctive advantage of my method of operation of the Oi system is that it may be possible, under certain conditions of the raw water chemistry of feeding and operation, to operate the entire chain of ion exchange after Oi, (ie exchange ion, units 40, 42, 44 and 46) without regeneration. Depending on the chemistry, it may be possible to simply replace the cation exchangers 40 and anions 42. In the most common case, the secondary unit or mixed polishing bed 46 can be replaced with new resin and the old polishing resin can be transferred to the position of the primary bed 44. This is possible, especially in ultrapure water treatment system or boiler feed, since the polishing mixed bed unit 46 is controlled upon completion of the operation at the time of the leakage of silica, boron or other ion reaches a predetermined value. When the predetermined ion leakage value is reached, the mixed polishing bed unit 46 is replaced and placed in the place of the mixed bed ion exchange primary unit 44. When the change of the exchange units has been made Mixed-bed ionic resin, resin 44 from the "old" mixed-bed primary unit is extracted, and disposed of or sold to other less demanding resin users. The new resin is then placed in the "old" primary mixed-bed ion exchange unit 44, which becomes the "new" polished mixed-bed ion exchange unit 46. In other modalities, and as appropriate to the needs In particular, a chemistry of selected raw feedwater can be used for various forms of hardness removal, including cation exchange 50 of strong acid in the form of sodium, followed by acidification (see Figure 3), or even softener lime 52 (or similar lime / soda) as an additional step of the pretreatment for the cation exchange 50 of strong acid 50 in the sodium form, or the cation exchange 12 of weak acid (see Figures 2 and 3). For especially mild waters, the lime / lime / soda softener 52 may be completely unsuitable, and this method will not result in the softening of the raw water, and only a simple acid feed 14 before decarbonization, as can be seen in Figure 4. On the other hand, when smoothing is appropriate, some raw feed waters can be treated well with the softener 52 for reductions in hardness and alkalinity to a desired degree. Regardless of the configuration of the selected equipment for the treatment of a particular raw water chemistry, the key parameters of the process are (a) to eliminate the cations that, in combination with other species present at a high pH, would tend to precipitate barely soluble salts on the surfaces of the membrane, and (b) eliminate the alkalinity without hydroxide to the maximum possible degree, to further protect against the precipitation of scale on the surfaces of the membrane. The weak acid cation ion exchange (WAC) resins used in the first step of the preferred embodiment of my method, as shown in Figure 2, are very effective for the removal of the hardness associated with alkalinity. This reaction occurs as follows: Ca ++ + 2RCOOH - »(RCOO) 2Ca + 2H + Then, hydrogen combines with bicarbonate to form carbonic acid, which when depressurized forms water and carbon dioxide, as follows: H + + HC03"- H2C03" H20 + C02 The regeneration of the resin is carried out using an available and cost-effective acid. It is known to those skilled in the art that the regeneration of the WAC ion exchange resins can function very efficiently at near stoichiometric levels (generally no more than about one hundred twenty percent (120%) of the ideal levels). Preferably, hydrochloric acid can be used, since in these cases extremely soluble calcium chloride would be produced, and the regeneration process would not represent a potential danger of formation of insoluble sulfate precipitates, such as calcium sulfate, even with high strength acids. . However, by using step-wise regeneration procedures, that is, using a low concentration acid and then a high concentration acid, it is possible to reliably use other acids, including sulfuric acid (H2S0), while avoiding at the same time the undesirable precipitates in the resin. In this way, the hardness ions are solubilized to form salts, which are washed from the resin bed and are usually discharged to the drain. The use of sulfuric acid is especially advantageous in semiconductor manufacturing operations, since such plants normally use large amounts of that acid and the spent acid can advantageously be used for the regeneration of a weak acid cation exchange bed. Other polyvalent cations, most commonly iron (Fe ++ / Fe +++), magnesium (Mg "" "), barium (Ba44), strontium (Sr44), aluminum (Al44") and manganese (Mn ^ / Mn4444), are also eliminated by a WAC resin. Due to the presence of lower amounts of hardness and other species of lower solubility at increased pH will result in the precipitation of hardly soluble salts according to the process conditions present in my process, care should be taken to avoid the precipitation of substances such as calcium carbonate, calcium hydroxide, magnesium hydroxide and magnesium silicate on the membrane. One caution that must be taken into account is that both the hardness and the alkalinity forms without hydroxide should be drastically reduced in the feedwater before the pH is raised to the selected Oi operating conditions. Once the hardness and alkalinity forms without hydroxide have been removed, then "the desired pH increase can be made with any convenient alkali source, such as sodium or potassium alkali, or by anion exchange. previous treatment has been completed, the Oi system can be operated safely at very high pH levels, in order to take advantage of the solubility of the aforementioned silica.In cases where the composition of raw water is such that it is advantageous the softening with sodium zeolite, as shown in Figure 3, the removal of the hardness by calcium proceeds as follows: Ca ++ 2¿ + Na2X - »CaX + 2NA Then, the alkalinity of the bicarbonate is converted to carbon dioxide with a selected acid, in a manner similar to the following: NaHC03 + HCl - NaCl + H20 + C02 For waters where softening with lime may be an acceptable method or is the preferred method for the initial reduction of hardness and alkalinity, the addition of lime to water reduces the hardness by calcium and magnesium, and the alkalinity of bicarbonate associated, as follows : Ca (HC03) 2 + Ca (OH) 2 - »2 CaC03? + 2 H20 Mg (HC03) 2 + 2Ca (OH) 2 Mg (OH) 2? + 2 CaC03 + 2 H20 This process configuration is represented as an alternate modality of my method, as shown in Figures 3 and 4. However, in cases where smoothing with lime or lime / soda is used, special care should be taken in evaluating the performance of the rest of the pre-treatment system, since the solubility of the hardness ions is still appreciable in the effluent stream 54 of the softener 52. For most of the feed waters, especially when a softening with lime or lime / soda is not used, the use of a Carbon dioxide removal stage makes the process much more cost-effective when carried out before increasing the pH. This also helps maintain a lower level of total alkalinity in the feed to the Oi, thus providing a much greater margin of safety against fouling due to hardness leaks from the cation removal stage. Decalcalisation by removal of carbon dioxide also helps to improve silica rejection, due to the lack of competing species. This is because the rejection of a barely ionized anion is affected by the presence and concentration of other barely ionized anions in the feed water; this applies to weakly ionized anions such as boron, organic acids (TOC), cyanide, fluoride, and certain arsenic and selenium compounds. Because the operation with high pH also increases the ionization of other slightly ionized anions, including borate, organic acids (TOC), cyanide, fluoride and certain arsenic and selenium compounds, their rejection rates are improved in a system of Oí membranes. Therefore, in general my method can be advantageously applied to reject the majority of weak acids in the entire membrane with a p ai of about 7.5 or greater. Silica rejection can rise to approximately 99.95%, or more, from a base of about 99% rejection; this amounts to at least one order of decreasing the amount of silica escaping in the infiltrate, thus providing a ten-fold (10+) increase in the operational life of the ion bed resin ion exchange silica scrubber, namely, anion exchanger 42 and mixed bed units. In the case of cyanide, rejections can be obtained in a first step Oi of more than ninety percent (90%), in contrast to the most common interval of about fifty percent (50%) with conventional Oi processes. Similar to the case of silica, boron rejection can be improved from a conventional baseline from a range of about 60-70% up to 99%) or more, by operation at an appropriately high pH. The beneficial effects on the percentage of rejection due to a higher pH operation initiate a slightly lower pH in the case of boron, since the pKa for boron is 9.14, approximately half a pH unit more than that of orthosilic acid , namely, 9.7. However, the beneficial effects of the operation at high pH are much more pronounced in the case of boron, since orthosilic acid (H2Si04) in aqueous solution normally includes six molecules of water of hydration, while boric acid (H3BO3) Normally it does not have hydrated water molecules attached. Thus, the orthosilic acid molecule is very large relative to the pore size of the membrane when compared to boric acid, no matter what the pH, and as a result the silica has much higher normal rejection rates. Accordingly, the increased ionization of boric acid when operating at a pH of more than 9.1 is extremely beneficial, and increases as the pH rises to 10 or 11, or the currently preferred control point of approximately 10.5. The effect of boron rejection would be even better when operating an Oi system at a pH of 12 or up to 13, when commercial membranes are available for that purpose.

EXAMPLE PILOT TEST A pilot water treatment system was prepared to test the efficacy of the indicated method. The pilot water treatment system was designed to treat the incoming municipal raw water supply to provide a high purity water for future potential use in a semiconductor manufacturing plant. The objectives were (a) to increase recovery, so that water consumption was minimized, (b) increase the purity of the treated water, and (c) increase the average time between membrane cleanings. The pilot system carried out a series of tests. In each of the tests, the system was started with 450 ppm or a higher level of silica in the rejection of the Oi. The pilot plant system was operated continuously until (a) a 10 percent (10%) decrease in the normalized water flow of the Oí infiltrate was experienced, or (b) an increase of fifteen percent was reached ( 15%) in the axial differential pressure across the Oi membrane. The pilot test was performed with a membrane separation unit that included a Dow / Filmtec OI Membrane Model FT30 / BW4040, which operated at pressures of between approximately 130 psig to approximately 185 psig, with feedwater temperatures of between approximately 20 ° C and approximately 25 ° C, and feed water velocities of up to about 8 US gallons per minute (30 liters per minute) maximum. As seen in Figure 6, long-term normalized inflitrate flows slightly greater than 5 US gallons per minute (about 20 liters per minute) were tested. The device for the pilot test included a pair of weak acid cation ion exchange beds operated in parallel, using weak acid cationic resin from Rohm and Haas Company (Philadelphia, Pennsylvania), product code IRC-86, followed by a decarbonizer with forced air, injection of sodium hydroxide, separation of the feed water treated by the Oi membrane within a reject current and an infiltrating stream.

Table 1 presents the chemical analyzes of the operation of the pilot plant for raw water, rejection of Oi, and infiltration of Oí. Table 1 also shows the rejection rates achieved in the pilot operation of the Oi, and compares the rates with those obtained with a conventional Oi system working with the same feedwater. In particular, note the level of silica in the raw feed water (67 ppm) and the rejection of the Oi (480 ppm). The concentration of silica in the rejection of the Oi is approximately three times that which is normally obtained in the reject water of the conventional process configurations of Oi. Furthermore, even at high concentration of silica in the rejection of the Oi, an improved rejection of the silica is observed, since a silica rejection of 99.81% was achieved, compared with rejections ranging from approximately 95% to approximately 99% of the conventional Oi system with the same feed water. In fact, improved rejection rates were experienced with all important chemical species compared to the rejection rates experienced with conventional OI, as evident in the data presented in Table 1. Specifically, the high boron rejection rates and TOC also provide an important additional benefit in reducing the charge of the downstream anion 42, and of the ion exchange units of the mixed bed 44 and 46. In this regard, note that a rejection of 98.51% or for the boron, compared to 60% to 70% that is achieved with conventional Oi systems with the same feedwater. Typically, the termination of an anion or mixed bed ion exchange run is determined by the leakage of silica, or in certain cases, boron. Despite the greater recovery in the Oi pilot system, the silica content in the infiltrate of the conventional Oi system was three times higher than that of the Oi pilot system. Specifically, silica concentrations of 0.45 ppm Si02 were reached in the infiltrate of the pilot unit of this method, compared with 1.5 ppm Si02 of the infiltrate in a conventional OI. Clearly, levels of less than 1.0 ppm of Si02 can be achieved in the Oi infiltrate when using the present method, and in fact it has been shown that levels of less than 0.50 ppm Si02 can be achieved. Also, the boron content in the infiltrate of my innovative process was 0.007 ppm B, in contrast to the 0.06 ppm B infiltrate of a conventional Oi system. Clearly, boron levels of less than 0.05 ppm were demonstrated, as well as levels of less than 0.01 ppm boron. The results of the test in Table 1 also show this result, in which the rejection of boron in a conventional Oi system varies from approximately sixty percent to seventy percent (60% -70%), while boron rejection in my water treatment process it was around ninety-eight and a half percent (98.5% »). In other words, in a conventional Oi process, about thirty to forty (30 to 40) borate ions pass through the membrane for every one hundred (100) present in the feedwater, while in my process, less than two, and specifically only about one and a half (1.5), borate ions pass through the membrane of every one hundred (100) present. That is, 30 of 100 or 40 of 100 borate ions in the feedwater reach the infiltrate in the conventional OI, in contrast to 1.5 out of 100 in this process. In certain feeder waters, this number will decrease further to as low as 1/100, or 1/1000, for boron rejection rates of ninety-nine percent (99%) or ninety-nine point nine percent (99.9 %), respectively. Thus, this indicates that the run times in an anion exchanger 42, while not necessarily proportional to the influent's silica and boron levels, will be significantly longer when dealing with an infiltrate 34 of my new process, compared to the times of corrida when dealing with the infiltration of a conventional Oí system. Because the depletion of the anion is indicated by a predetermined level of silica leakage (Si02), and in certain cases of boron, and because the concentration at the exit of the resin bed is related to the average concentration of species in the bed of resin, by achieving a significant reduction in the concentration of said anions in the influent that goes to the bed of anion ion exchange resin, the consequence is that longer run times are obtained before the maximum leak is reached allowable of Si02 or boron.

Table 1 ANALYTICAL RESULTS OF THE PILOT TEST Table 2 Effects of Sodium Ion Exchange Table 3 RESULTS OF THE IONIC EXCHANGE SUBSEQUENT TO MIXED BED It is important to note that the levels of boron and especially silica and TOC were extremely low after treatment of the infiltrate 34 in the mixed-bed ion exchangers 44 and 46 in the pilot plant. A comparison is provided with the subsequent mixed-bed infiltrate of a conventional Oi process with the data in Table 3. Significantly, in my new process, in the water after being treated by mixed-bed ion exchange, the level of TOC was less than 3.0 ppb, that is, below the detection limit. In addition, the greatly improved rejection of sodium and potassium should not be overlooked, which improved to 99.73% and 99.98% respectively, compared to the rejection rates of a conventional Oi system, ranging from ninety five to ninety and eight percent (95%) - 98%) in the case of sodium, and from ninety to ninety-five percent (90% - 95%) in the case of potassium. The significantly greater rejection of strongly ionized species such as sodium, potassium, chloride and sulfate, compared to the operation of a conventional OI as shown in Table 1, was an especially important and unexpected experimental result of the pilot test. Furthermore, even though the Oi infiltrate in the pilot plant test contained a higher level of sodium than the infiltrate of the conventional Oi process, as shown in Table 2, the impact of the higher sodium content on the subsequent exchange OI cationic is relatively insignificant. Because the Oi infiltrate of my innovative process is very alkaline (a typical pH of 10.3 during the pilot test is shown in Table 1) and it contains significant levels of free hydroxide ions, the degree of sodium removal and the capacity of the resin in the cation exchange unit 40 was increased to a substantial margin. The effect of the increased hydroxide alkalinity in the infiltrate to improve the removal of sodium from said infiltrate is presented in Table 2. In the conventional treatment of Oi of the same feed water, where the infiltrate of the Oi system had only 193 ppb of sodium, the ion exchange resin of cations could only perform the elimination of sodium at approximately 0.431 ppb. In contrast, my innovative process, although it encountered 955 ppb of sodium in the Oi infiltrate after cation ion exchange treatment, the concentration of sodium ions was reduced to less than 0.007 ppb.

The improved rejection of total organic carbon ("TOC") in my process also provides an important benefit to the operators of the Oí plants. It is normal for waters of natural origin to contain detectable amounts of high molecular weight organic acids and their derivatives, especially humic, fulvic and tannic acids. These compounds result from the degradation of plant matter, and are usually related to condensation products such as phenol compounds. In a broad sense, humic acids include the fraction of humic substances that are soluble in water at alkaline pH, but that precipitate at an acidic pH. Fulvic acids include the fraction of humic substances that are soluble in water at alkaline and acidic pH. These acids, and their products of decomposition, can be transported in the feed water stream and form undesirable deposits on the selected substrates, especially the anion-selective substances. In addition, they tend to contribute to pollution in conventional Oi systems. Therefore, it is desirable to minimize the effect of said molecules on or throughout the reverse osmosis membrane, so that the adverse consequences of its presence can be avoided., especially in the anion ion exchange unit. As can be seen in Table 1, the TOC content of the infiltrate 34 is substantially lower compared to the TOC of a conventional Oi process with identical TOC in the raw feed water. Specifically, there is a rejection of ninety-nine point sixty-six percent (99.66%) of TOC in the Oi system of the pilot plant, compared with only ninety to ninety-five percent (90% -95%) of recovery in conventional Oí systems. As in the cases of silica and boron, the increased ionization of TOC at high pH of my new process is attributed to this important result. Thus, taking advantage of the ionization range of the ionizable organic carbon species allows effective reductions in TOC when operating Oi systems in accordance with the method established here. The operating results of the pilot test unit can also be better appreciated with reference to Figures 5, 6, 7 and 8. Figure 5 illustrates the relationship between axial differential pressure (? P) versus time, in pounds per square inch, for the reverse osmosis membrane used in the reverse osmosis pilot test equipment. The differential pressure shown has not been corrected by changes in the flow rate of the feedwater. Compared to a conventional OI, the results of the pilot test show that a stable normalized infiltration rate of the infiltrate, a stable silica rejection rate, and a stable differential pressure have been achieved. This indicates that the contamination / fouling has been essentially removed with my new process. Figure 6 shows the normalized infiltrate flow, in liters per minute, versus time in a period of six months, for the reverse osmosis membrane used in the reverse osmosis pilot test equipment. Figure 7 shows the concentration of silica in the reverse osmosis reject stream over a period of six months in the reverse osmosis pilot test equipment. Figure 8 illustrates the percentage of silica rejection versus time in a period of six months for the reverse osmosis membrane used in the reverse osmosis pilot test equipment. This rejection of silica is based on the arithmetic mean concentration of silica in the OI pilot unit. After each stoppage of the operation of the pilot plant, due to a drop of ten percent (10%) or more in the normalized flow of the infiltrate, the membranes were inspected and cleaned. An important discovery was that cleaning could be done easily and efficiently using membrane cleaning chemicals, such as solutions of hydrochloric acid, tetrasodium EDTA and hydroxy sodium. No expensive chemical cleaning agents were required. It was demonstrated that an Oi membrane operated with pretreatment of the feedwater in the manner set forth herein was completely restored to a flow essentially of one hundred percent (100%) of the performance values at start-up. Almost all cleaning was performed in the first stage of acid cleaning, which indicated that sodium carbonate, magnesium hydroxide, magnesium silicate and the like were the predominant species of scale formation. It is important to note that this revealed that neither the formation of silica scale nor the biological contamination were important aspects under the specified conditions of the process. Improved functionality, or increased system availability, with minimal inlays or almost nonexistent contamination, is another important benefit of my innovative Oi operating method. Biological contamination of thin film composite membranes has so far tended to be a common problem and, with certain specific feed water sources, has been practically insurmountable. Although it was anticipated that the control of biological contamination would improve due to an operation at relatively high pH levels, the degree of control of the biological contamination actually reached exceeded expectations, with levels of bacteria that were almost not detected during the autopsy of the elements of the Oi membrane. This means that instead of accumulating live and dead bacteria on the surface of the membrane, as with conventional Oi systems, with my unique method the incoming bacteria were killed and dissolved from the surface of the membrane. Thus, this method of Oi pre-treatment and operation can be very useful to treat problematic water sources. This is effective because solutions with high pH cause disinfection by cell lysis or rupture of the cell wall. This is a fairly powerful and fast-acting method of antibacterial activity when compared, for example, with chlorination that acts by a rather slow diffusion method throughout the cell wall to cause death by inactivation of the enzymes of the cells. microorganisms. Also, in contrast to the chlorine disinfection systems, at the one high pH operation preferred in the present method, viruses and endotoxins (fragments of lipopolysaccharide derived from the cell walls of Gram negative bacteria) are efficiently destroyed by lysis, allowing the present method to be used for the production of sterile or pyrogen-free water. In essence, this method, when operated at a pH of more than 10, provides sanitization (logarithmic reduction of 3 in bacteria and destruction of vegetative matter), and also demonstrated that it provides true sterilization (logarithmic reduction of 12 in bacteria and elimination of biological layer and spores) of the process equipment, since the results of the test showed a count of zero (0) bacteria in the infiltrate. Likewise, it should be noted that the increased pH of the infiltrate in this method of operation allows similar results to be useful in the treatment equipment subsequent to Oi. Said method of operation will be of particular benefit in the production of high purity water for pharmaceutical applications, where the final water must necessarily comply with the requirements of the United States Pharmacopoeia 23 standards ("USP 23), and supplements. In this regard, by avoiding the use of raw water polymers, anti-fouling products and other proprietary chemicals for pre-treatment by Oi, as described herein in relation to a preferred embodiment, undesirable additives can be eliminated for pharmaceutical grade water. , and reduce costs by decreasing the necessary tests in Oí's product water, more concisely, the selection of a pH for Oi operating conditions that do not support bacterial growth, and leading to the elimination of hardness and alkalinity at a level that avoid the use of additives, it is an optimal method for the production of high purity water. of an operation with high pH is the increased protection of the membranes, especially those of the thin film composite type, which have a minimum tolerance to oxidizing agents at neutral, almost neutral, and moderate alkaline (up to about 9). When chlorine is added to the feed water of the Oi, chlorine gas (Cl2) or sodium hypochlorite (NaOCl) is usually used. Due to the sensitivity of the membrane to free chlorine, in conventional Oi systems, it is usually removed by sulfite injection (S03 ~). However, a pH of more than 9, especially more than 10, the effect of chlorine and other similar oxidants on the thin film composite membranes is greatly reduced. This is because the concentration of non-ionized species (such as HOC1, known as hypochlorous acid) is drastically reduced, since such acids are relatively weak. Therefore, in my HERO ™ high pH reverse osmosis process with typical operation at pH 10 or higher, the removal of chlorine is not necessary, thus reducing the complexity and costs of the system. This is especially beneficial for systems that use municipal water as feedwater for the treatment plant. The long life of the membrane is also another benefit of my innovative membrane operation process. In membrane operations, and in particular with respect to the operations of Oi, a prolonged life of the membrane element can be expected, mainly due to the avoidance of scale formation and biological contamination, and therefore it is reduced in size. drastic exposure to severe cleaning chemicals (eg, acids and surfactants). Oi membranes are removed from operation when the rejection of critical species such as silica, boron and TOC falls below an acceptable limit. For silica, this usually occurs when rejection drops to between ninety-five and ninety-six percent (95% -96%), from an original value of ninety-nine percent (99%), or more. As discussed above, the initial rejection values for silica in my process are significantly higher than those achieved with conventional Oi systems. Therefore, if for example the limitations of the conventional Oi for the rejection of silica were accepted, for example, a specific element of a membrane would last longer, before acceptable limits were reached. In other words, even after a considerable period of service, the membrane elements used in the present method would give silica rejections much greater than those provided even by new membranes operating in conventional Oi process configurations. High flow, or infiltration production, can also be achieved due to the unique operating conditions of my method to operate an Oi system. Several factors contribute to this result. The flow, expressed in gallons of water that pass through a square foot of membrane in a day, usually called "GFD", is anticipated to be around 15 GFD for conventional Oi systems. In the pilot test, the aforementioned BW membrane of FILMTEC type composed of thin film was operated at 24 GFD, and a potential for up to 30 GFD was favorably evaluated. Although it is believed that this last flow rate is the current approximate hydraulic limit of the conventional design of the Oi module, based on larger configurations, it is anticipated that an increased flow can be achieved with this method of operation (up to about 50 GFD) when It has membrane modules that can support this increased flow. This is a very advantageous result for the operators of the Oi systems, since for example, if the normal flow is duplicated using this method, then the total square footage required of the membrane surface is reduced by a factor of two. Therefore, corresponding decreases in capital cost (specifically for membranes and pressure vessels) and space requirements can be obtained. The operating cost, already reduced by the other benefits of the present method, will be further reduced by lowering the replacement costs of membranes. The increase of one hundred and fifty percent (150%) more in the flow that was obtained in the test above the design basis of the conventional Oi systems, provides an immediate benefit. When the present method is employed, the osmotic pressure of Oi rejection represents the fundamental limitation for Oi technology. Once the proper treatment of the raw feedwater has effectively eliminated the sparingly soluble species, such as calcium carbonate, calcium sulfate, barium sulfate, silica, etc., then the reject concentration can be followed until the osmotic pressure limit. At this time, the design pressures for commercially tested Oi systems are usually limited to roughly 1, 200 psig. If a design is permitted for a motor force of 200 psig with respect to the reject current, then the maximum permissible osmotic pressure would be approximately 1000 psig. As an example, based on a simplified rule of thumb that approximately one (1) psig of osmotic pressure is exerted at one hundred (100) ppm of TDS, the maximum allowable TDS of the reject current would be around 100,000 ppm. Thus, this new Oi operating technology, regardless of the chemistry of the feedwater, is potentially capable of concentrating any feedwater at approximately 100,000ppm without worrying about the various sparingly soluble species, and in particular calcium sulfate, sulfate of barium and silica. One more advantage of my new Oi operating technology is that existing Oi systems, when retrofitted with the pretreatment equipment described here for hardness and alkalinity removal, can take advantage of the operating benefits of this process method. Additional applications for this unique Oi operating method are found in both high purity applications such as for semiconductor fabrication, as well as for more traditional industrial applications and pharmaceutical applications for boiler feed water, add-on water / tower fill of cooling, and water complement / filler for washers. The application of my method of operation of a reverse osmosis system in high purity water production systems is shown in Figure 9. In this figure, a multiple step reverse osmosis process technique is used to process a portion in sequence of the initial feed raw water 10 to produce a final infiltrate 34 (>; + N) that passes in sequence through a number N of reverse osmosis membrane units, where N is a positive integer, usually two (2) or sometimes three (3), although a larger number can be used. As described above, the raw feed water 10, if deficient in alkalinity, can have an increased alkalinity by any convenient technique, such as with sodium carbonate 13, and then the treated stream Rc is sent to an ion exchange system of weak acid cation 12. After cation exchange, acid 14 can be added, such as hydrochloric or sulfuric, to produce a WA treated intermediate stream. Subsequently, the carbon dioxide is withdrawn in the decarbonisation unit 20 to produce an intermediate treated stream D. Then, the pH is raised as a convenient and cost-effective method, such as by the addition of alkali solution 22 or by ion exchange unit. anions 31, to produce a subsequent current of intermediate treatment DOH. The rejection 32 (N) of the reverse osmosis unit N (and any intermediate unit of Oi between the first unit of Oi 30 (i) and the final unit of Oi 30 (N) are then recycled into the feed water before the OI 30N unit, to produce a feed water 25 (i + N) containing undesirable but tolerable solute species and solvent water The pump 26 pressurizes the feed water 25 (i +) to produce a pressurized feed to the first unit of Oi 30 (i), after the process, the infiltrate 34 (i) appears and is then fed to the next unit of reverse osmosis of the series of 1 to N. The rejection of the entire sequence of Oi is presented as rejection 32? + N) The high purity treated infiltrate from the entire sequence is shown as infiltrated or water product 34 O + N), and fed to the usual ion exchange equipment for final cleaning before use. The ion exchange unit of cation 40 produces a subsequent intermediate stream of purity C, which is followed by an ion exchange unit of anions 42 to produce another intermediate intermediate stream of purity A. Before use, a bed ion exchange unit primary mixed 44 produces another still greater purity stream P, and an optional secondary mixed or polished mixed bed ion exchange unit 46 produces an even higher purity, the final possible purity product S, or using the same nomenclature above, a current of pure product water 38 (? + N). In the manufacture of semiconductors, the final filtration is usually used in filters of less than one miera 48, with filters of nominal size of 0.02 microns (although selected perhaps from sizes that vary between approximately 0.02 microns to around 0.1 microns, for producing an even greater product stream M. Also, biological control is usual by passing the high purity water through a UV sterilization unit 49, operating generally at a wavelength of 254 nm to kill any bacteria that may be present in the high purity stream M and 3g resulting in a final ultrapure water U. In many systems, the order of the final filters of less than one 48 may be reversed, and the sterilizing unit 49 may be inverted, or an additional filter subsequent to UV may be used. Figure 10 shows the use of my method of operation in a reverse osmosis system for add / fill water for boiler feed, or for cooling towers, or for washers. The reverse osmosis unit 30, and various pretreatment equipment, is operated according to the previously established methods to produce high purity infiltrate 34. The water infiltrate product 34 is then treated with an ion exchange system as necessary according to the specific requirements of the boiler, and is fed as add / fill water 100 to the boiler 102. The purge 104 of the boiler 102 is sent to an accumulation tank 106 to be pumped 108 through the return line 109 to the Oi pre-treatment train. Although the cooling tower 110, and the scrubbers 112 could be fed with the infiltrate of Oí 34, it is more common for the cooling tower 1 10 and the scrubbers 1 12, for example in a thermoelectric plant, to be fed by common water supplies raw 10, as municipal or well water. Chicken therefore, the purge 1 14 of the cooling tower and the purge 116 of the scrubbers is normally high in hardness and in alkalinity. Likewise, this system can be used to treat water that has a close contact with ash, such as water from an ash dam pond, or ash wash water from coal-fired thermoelectric plants. In my reverse osmosis process, an important amount of reusable water can usually be obtained, by means of my method of previous treatment and Oi operation, unlike conventional Oi systems. Another advantageous use of my method for the pre-treatment and operation of an Oi system is presented in Figure 11, where a preferred modality similar to that explained above is shown, with a multiple-pass OI system (here, two steps). with units of Oi 30 (D and 30 (N), where N = 2), in the pretreatment for a continuous electrodeionization system 150. The infiltrate of Oí 34 (i + N), when treated by continuous electrodeionization, will produce deionized water of very high quality E, which, after treatment with ultraviolet radiation 46, and final filtration 48, will be acceptable for use in the microelectronics industry as ultrapure water UP As an option, the bed ion exchange unit can be omitted mixed secondary or polishing type 46, and the water product of the continuous electrodeionization E can be sent directly to the sterilization unit with UV radiation 49. This is true since the limitations of the to continuous electrodeionization to reject boron, silica, TOC and the like, limits its capacity to produce, as a direct effluent, water of 18.2 mega ohms for the manufacture of electronic components. Even so, infiltrate 34 (I + N) of the double-pass Oi system, when operated according to the method presented here, contains very low levels of said species that are problematic for continuous electrodeionization, such as boron, silica, TOC and similar. Therefore, it is considered that the use of said infiltrate as a feed for a continuous electrodeionization treatment unit allows said electrodeionization units to produce water of 18.2 mega ohms without the benefit of downstream ion exchange polishers 46. The advantage of using continuous electrodeionization compared to conventional ion exchange is, of course, that the continuous process (instead of the batch process of the ion exchange resins) is regenerated electrically and not chemically, and therefore avoids the use of chemicals conventional for regeneration. further, the method of the present invention can be exploited even in wastewater. Because an Oi system, when operated as indicated here, will substantially reject ionizable species at a high pH, high rejection of these components will be obtained to produce a low Oi infiltrate in said components, for recycling and re-use. Wastewater from refineries, pulping and papermaking operations, and municipal sewage treatment plants, all have a high content of difficult components (aliphatic acids and / or organic aromatics and their derivatives), and are the more problematic waters for the management by the conventional membranes of Oí, due to the organic contamination and the corresponding biological growth. Typical industrial uses where water of sufficient quality can be obtained when the wastewater is treated include cooling towers, boilers, scrubbers, and the like.

Benefits of the Design and Operation of the HERO Brand Process Many desirable and exemplary process benefits provided by the design and operation of the HERO brand OI system process were listed above on pages 22-23. The detailed explanation of said benefits includes: (A) High Contaminant Rejection As shown in Table 4, which summarizes the data from the pilot plant of the Oí brand HERO process, the rejection of all the species is significantly greater than that it is obtained with the conventional operation of Oi. Of special importance is the improvement in the rejection of weak anions such as TOC, silica and boron. Since the derivatives of humic / fulvic acid (TOC), silicic acid and boric acid are all relatively weak acids, at a high operating pH, these acids dissociate to a much greater degree (compared to the operation at near neutral pH) , and therefore will be better rejected by Oi's membrane. There was also an improvement in the rejection of strongly ionized species (at an almost neutral pH). It is believed that several factors contribute to the improvement in the rejection of highly ionized species. It is thought that a change in the morphology of the membrane occurs. It is also believed that a significant reduction in the thickness of the concentration polarization layer adjacent to the surface of the membrane (due to reduced surface tension at high causticity-free conditions) is a major aspect contributing to this improvement. In addition, the widening of elastomers such as gaskets and the resulting improved sealing characteristics in the modules are also a contributing factor to the improvement. The impact of a much greater rejection of silica, etc. in the behavior / operation of a ion exchange system subsequent to Oi is extremely important. Because the large part of the ion exchange subsequent to Oi is regenerated based on the point of leakage of silica or boron, a reduction factor of ten in the silica / boron content of the influent will provide much longer run times between regenerations. . The absence of carbon dioxide, as well as bicarbonate, in the Oi infiltrate (due to a high pH, usually at least 10), will also increase the on-line time before the boron / silica leak exceeds the threshold values normal. The reduction in the concentration of highly ionized species in the Oi infiltrate is of relatively minor importance, since most of the ion exchanges subsequent to Oi are ultimately limited to silica and boron.

Compared with boron rejection of 60 to 70 percent in the conventional Oi operation of thin film composite membrane, the new process provides about 99 percent boron rejection. In a double-pass configuration, the new process is capable of producing an infiltrate with a lower content of detectable boron limits. Table 4 COMPARISON OF THE Oí HERO ™ VS. I heard CONVENTIONAL Table 5 WATER ANALYSIS Notes: 1. The analysis of the Oi feed is not shown in the table, nor the hydroxide content of the Oi reject and the OI product. 2. The chemistry is based on 90 percent recovery of the OI, while the maximum feasible recovery is approximately 96 percent. 3. Except for pH, all components are indicated as mg / l, such as CaCO3.

Table 6 ESTIMATED COST OF READAPTATION Savings in Water / Residual Water 244,000 (US $ / Year) Elimination of antifouling 30,000 (US $ / Year) Energy Savings 17,000 (US $ / Year) Additional Cost of Chemicals (40,000) (US $ / Year) Miscellaneous Additional Costs (20,000) (US $ / Year) Net Annual Savings 231, 000 (US $ / Year) Conversion Cost (Capital) 200,000 (One time only) Simple Investment Recovery Period 10.4 (months) Table 7 COST COMPARISON Note: See section 5.0 for the base Another very important advantage in the operation of the ion exchange with infiltrated system of Oí brand HERO is that the sodium leakage of the cationic resin is reduced by several orders of magnitude, due to the high pH environment of the influent. As a result, the longer run times between regeneration for existing ion exchange systems mean lower requirements for chemicals and labor, lower volume of regeneration waste, etc. For new systems, or for existing systems that are expanding, the new design and operation of the HERO brand OI can also have a strong positive impact on the capital cost of the ion exchange system.

(B) Elevated Proportions of Recovery Because the ions that cause hardness, such as calcium, magnesium, barium, strontium, aluminum, iron, manganese, etc. have been eliminated before the Oi, the undesirable precipitation of species such as calcium carbonate, calcium fluoride, calcium sulfate, barium sulfate, magnesium hydroxide, aluminum / magnesium silicate, etc., does not occur in the process of I heard HERO brand, and therefore that kind of precipitation no longer limits the recovery that can be achieved with an OI system. It is important to note that the solubility of the silica increases drastically at the normal operating pH of the OI brand HERO (preferably about 1 1). The long-term sustainable operation has been proven with silica levels within the range of 450 to 500 ppm (in the rejection of 10); and the theoretical models indicate that levels of 1,000 ppm or greater can be reached with this new operating method of Oí. Based on 25 ppm of silica in the Oi feed, an Oi operation with 95 percent recovery was obtained in the tests (approximately 500 ppm in the rejection). Even so, it is theoretically possible to obtain a recovery of 97.5 percent (approximately 1, 000 ppm of silica in the rejection of Oi), whether or not it is practical from the point of view of the operation. Because silica usually represents the main limiting criterion, in terms of the maximum allowable recovery in an Oi system, the increased solubility of silica together with the almost total absence of species such as calcium, barium, etc., in Oi feed, should allow an Oi operation at very high recovery rates (90 to 98 percent) with the vast majority of feed waters.

With relatively high feed water in barium content, recovery of the Oi system can be limited by the potential precipitation of barium sulfate at the reject end. The HERO system eliminates this problem too, since the barium is quantitatively eliminated before the OI. The same result also applies to limited Oi systems (in their recovery), strontium sulfate, calcium sulfate, calcium fluoride, and other sparingly soluble calcium, magnesium, iron and aluminum salts. Of course, the final limit in the recovery of Oi, represented by the osmotic pressure of the rejection of the Oi, will control in any case the maximum recovery feasible to reach with a specific feedwater, but usually this limit is not reached at recoveries of less than 99 percent with most of the feedwater.

(C) Biological contamination is practically eliminated Most of the microbial species commonly present are lysed (physically destroyed) at high pH of operation. In fact even viruses, spores and endotoxins are destroyed or incapacitated to reproduce / proliferate at very high pH levels. It is expected that the saponification of the lipids (fat) plays a role in the process as well, since the fatty acids and their corresponding glycerides will form soluble "soaps" at high operating pH. In a place where long-term tests were carried out, the absence of biological contamination during the HERO technology test was notable. This pilot system of Oi presented a very stable operating performance in terms of the normalized infiltration flow and the drop in system pressure throughout the test period. Subsequent confirmation of the absence of biological contamination was obtained during the autopsy of the elements of Oí at regular intervals. A program in stages to test and autopsy elements based on FT30 of FILMTEC was carried out in a period of 15 months. The data showed greater rejection of salts than the initial values of Quality Assurance, under standard test conditions. In addition, the surface of the membrane was clean and free of any evidence of biological contamination. This feature of the new process can be an important benefit for plants with problems of biological contamination or for the treatment of biologically or bioactively contaminated wastewater. It can also be very effective for systems with Oi operation at a higher temperature than the environment.

(D) Particle Pollution Is Substantially Reduced It has been known (and has been carried out) for 30 years that the softening of the feed water of the Oi destabilizes the colloidal solids present in the feedwater and significantly reduces the problems associated with pollution. The mandatory requirement of smoothing as a pre-treatment for hollow fine-fiber Oi elements in the late 1960s and early 1970s is testimony to this strategy. In addition, the zeta potential is generally reduced between a surface and the contaminating particles at a high pH, thus decreasing the likelihood of adhesion. This property is accentuated by the fact that most of the natural particles (including bacteria) present negative surface charges. While the collateral determination of the zeta potential is still to be carried out, it is expected that the new process will greatly reduce, or eliminate, the problems of particulate pollution. The reduction of the zeta potential further reduces the possibility of particle adhesion to the membrane surfaces with slightly negative charge. The in situ formation of surfactants from bacterial lipids, if any, will further help to reduce the adhesion of particles to the surface of the membrane. This unique feature of the new process can have an important value in the design of an Oi system, especially in the potential to reduce capital costs and complexity of the UPW treatment operation. In addition to the ability to accept a certain level of contaminating particles, the new process can also minimize the need for multimedia filtration, addition of coagulant / flocculant, filtration with diatomaceous earth, etc., as a pre-treatment for the OI system. .

(E) Significant Reduction in the Consumption of Chemical Products The elimination of chlorine may also be unnecessary, either by chemical addition or by activated carbon, since the level of free (non-dissociated) hypochlorous acid (HOCL) is extremely low. Very high operational pH level.

(F) Elimination of the Use of an Incrustation Inhibitor The use of antifoulants or scale inhibitors, although not harmful or incompatible with the new process, can be completely eliminated, as was demonstrated in an 18-month test in a plant semiconductor manufacturing.

(G) High Flow Rates Given the reduced thickness of the concentration polarization layer, as well as the elimination of biological contamination and the reduction of particle adhesion to the surface of the membrane, it is not surprising that a system of Oi that use the new process can operate at a higher flow, compared to conventional operation. Compared to the normal flow of 15 gfd (gallon per square foot per day), the Oí brand HERO system is designed for more than 15 gfd, and preferably around 20 gfd, or better yet up to 25 gfd and when feasible , above 25 gfd.

(H) Greater Product Purity In addition to the reduced capital cost for the Oi system, the quality of the Oi infiltrate is greatly improved due to the greater flow of this design. For example, at 25 gfd, the Oí infiltrate will contain 40 percent less dissolved solids compared to the basic design of 15 gfd. The operation at higher pH, in combination with a greater flow of product, results in the flow of salts (which depends on the concentration, instead of the pressure) being reduced significantly. The Oi system is expected to be approximately 20 percent less expensive due to this factor itself (or more than 20 percent less expensive), with all other parameters equal. (0 Rejection can be used as Complement Water / Washer Filling The rejection of the HERO brand OI system, with high pH, low carbonate alkalinity, and practically no hardness, can be used as add / fill water for washers Acid gas Due to the aspects of the potential precipitation of silica, if the pH is significantly reduced in the scrubber, the rejection of Oi can be used based on a single pass, and therefore would not be limited to the proportion of evaporation.

Process Chemistry As stated before, the very high rejection pH is a factor that characterizes the operation of the Oí brand HERO system. An extremely high rejection of weakly ionized ions such as TOC, silica, boron, etc. it may be correlated with these characteristics. The following example, based on silica, can be used to explore this relationship. In waters of natural origin and at an almost neutral pH range (6-8), silica occurs mainly as orthosolic acid (H SiO). Orthosilicic acid, commonly known as silicic acid, is one of the weakest acid species present in water. The first dissociation constant of silicic acid (ie the dissociation of the first proton from a total of four hydrogens) is about 2 x 10'10, which corresponds to a pKa value of about 9.7 at room temperature and ionic strength very low background of the solution.

A convenient way to visualize the relative strength of silicic acid with pKaj of 9.7 is that at a pH of 9.7, the acid is fifty percent (50%) ionized, that is, 50 percent is present as undissociated orthosilicic acid, while the other 50 percent is dissociated and present as an ion monovalent silicate, the base of the orthosilicic acid conjugate. At a pH of 10.7, when the logarithm of the base of the conjugate with the dissociated acid is unity, about 91 percent exists as a silicate ion, the other 9 percent as undissociated acid. At a pH of 1.7, the distribution is 99 percent and 1 percent respectively. Conversely, at a pH of 8.7 (when the logarithm of the ratio is 0.1), approximately 91 percent of the species is present as undissociated acid and 9 percent as ionized silicate. At a pH of 7.7, approximately 99 percent is present as undissociated silicic acid and 1 percent as the monovalent ionized silicate ion. Because most of the natural feed water has a pH of 8 or less, almost all of the silica is present as non-dissociated silicic acid under these conditions. Other very weak acids, such as boric acid (H3BO3, with pKa of about 9.3) and hydrocyanic acid (HCN, with pKa of about 9.3) have very similar properties, although of course, both are somewhat stronger acids compared to the silica. The rejection characteristics of individual species throughout the Oi membrane is influenced by the size, shape and density of the solute charge. It is known that an ionized solute will be rejected much better than a solute that exists in an undissociated state, as long as its size and shape are comparable. The rejection of fluoride, for example, is essentially zero at a pH of less than 3.30 percent at a pH of 3.5, 50 percent at a pH of 4.75 percent at a pH of 5, and 98 percent (or more) at a pH of 7. Hydrofluoric acid (a weak acid with pKa of 3.2) is the counterpart of the ionized fluoride species and is the primary component at low pH values. However, the silica / silicic acid rejection is surprisingly high at 98 percent at a pH of 7, when the primary component is undissociated silicic acid and not ionized silicate species. This discrepancy is explained at least partially by the fact that the actual size of the silicic acid (ortho) is much larger than expected since the molecule incubates up to six molecules of water of hydration. Thus, the high rejection is due to the size / shape factor, since at the pH of 7 there is very little ionization (less than 2.0 percent) of silicic acid. Based on the factors involved, it would appear that silica, when substantially ionized, should have a rejection comparable to that of the sulfate ion (S04). This assumption is based on the fact that the sulfate ion also incorporates six hydration waters and, of course, is completely ionized at almost neutral pH values. As reference, a rejection of sulfate of 99.5 and 99.9 is commonly observed in the normal operation of Oi, and the rejection of the silica in the HERO system at a pH of 10.5 to 11.0 has been much higher than 99.9 percent. In other words, the rejection of sulphate at pH 7 and the rejection of silica at pH of more than 10 are quite similar. Considering the relative forces of the corresponding acids and the relative size of the molecules, this effect can be rationally explained and used. Another aspect of the new process that deserves more detail is the requirement for an essentially complete removal of the alkalinity before adjusting the pH (increase) for feeding the Oi. From a totally practical point of view, almost zero alkalinity is a necessity, since any residual alkalinity will provide a strong regulator effect and a substantial increase in the amount of alkali necessary to raise the pH to the normal range of operation. In addition to the direct cost of the need for an increased alkali, the sodium content of the Oi infiltrate will be much higher as well, resulting in a cost and loading of ion exchange subsequent to the unnecessarily high OI. However, from a conceptual point of view, the requirement for removal of alkalinity is much more urgent, although direct. The following example, based on the solubility of calcium carbonate, will be used to quantify the relationship. The solubility product (Ksp) of calcium carbonate is about 8.7 x 10"9 molar square at room temperature and very low ionic strength, assuming that the goal is a 90 percent recovery throughout the OI, the The maximum permissible product of the CaC 3 ion from the feed to the Oi is approximately 8.7 x 10 '"square molar. Assuming in addition 0.1 mg / l of calcium in the softened feed water, the maximum allowable carbonate content for the Oi feed is around 2.1 mg / l. all expressed in ions.

In a rejection condition of pH 11, approximately 85 percent of the carbonate species (s) are present as carbonate, and the remainder as bicarbonate. Assuming 5 mg / l of equivalent residual total carbon dioxide before the pH increase, about 5.8 mg / l of carbonate (as ion) will be present in the 01 feed. Compared to the 2.1 mg / l maximum allowable carbonate, the 5.8 mg / l obtained are three times higher. To ensure an incrustation-free operation at a 90 percent recovery, one or more of the following should be considered: the residual calcium content should be less than 0.1 mg / l, or the operating conditions of the Oi should be modified. Although it is known that inhibitors of calcium carbonate scale generally allow a high Ksp, I do not know of any formula that allows a continuous Oi operation at high pH to be effective and inexpensive. It is important to note that during the long-term tests of the HERO system, no scale inhibitors were used in any case. Magnesium hydroxide, with a Ksp of about 1.2 x 10 * cubic molar, is in some way even more demanding in terms of allowable residuals, since magnesium tends to prematurely escape from the weak acid cation exchanger, and therefore more care is required to avoid formation of magnesium hydroxide inlays.

TYPICAL EXAMPLE The following is an example of a typical application of the HERO system. Feeding water in the Kimamoto area in southern Japan, high in silica content, was selected for this example. The costs presented are based on the budget (+ or - 30 percent accuracy). A cost projection is based on the following assumptions: (1) nominal system capacity of 1, 500,000 US GPD; (2) normal recovery ratio of 75 percent vs. HERO system recovery rate of 90 percent; (3) The criteria for the UPW (chemical) quality are: (a) silica < 1 PPB, (b) TOC < l PPB, and (c) oxygen < 5 PPB; (4) Cost of consumables: (a) sulfuric acid (93 percent) to US $ 100 / ton; (b) sodium hydroxide (100 percent) at US $ 450 / ton (c) antifoulant at US $ 1.50 / lb; (d) electricity at US $ 0.075 / kwh; (e) purchase of water and wastewater discharge costs (combined) at US $ 3/1, 000 US gallons.

Conversion of the Existing System of Oi Table 6 below assumes the conversion of an existing system of 1.5 million GPD (US) operating at a 75 percent recovery with feedwater as shown in Table 5, to a system of Oí brand HERO process with 90 percent recovery where no more changes are made except in the Oí system. In some cases, it may also be feasible to use an OI brand process design HERO to increase the overall recovery proportions of Oi, processing the rejection of a conventional Oi system, through (a) simultaneous reduction of hardness and alkalinity in a WAC system, (b) decarbonization, and (c) elevation of pH before feeding the current to a second system of Oi. The conversion of existing systems can also provide unique opportunities to raise the capacity of an Oi system. This is possible because the flow of about 15 gfd in a conventional Oi system can be increased to about 20 gfd, or perhaps up to 25 gfd, or more, when the operation is modified to the process design and operational configuration of Oí brand HERO.

New Design and Operation of the Oi System The projection in Table 7 below is made based on the totally new construction of two UPW systems, using in one case the conventional approach (see Figure 13), and in the other case using the system of I heard the HERO brand (see Figure 14), which includes a simplified polishing cycle design. The two systems will use a double pass Oi, ultra thin hollow fiber filter and non-dual bed ion exchangers. Approximately 40 percent of UPW consumption will be at elevated temperature, and the cost estimate includes DIW heaters. The pipeline system beyond the ultrafiltration system is not included in the cost estimates, nor is the installation of the system, nor any storage tank covered with PVDF, since the dimensions of these components are very particular in each case. plant.

Conclusions It has been demonstrated that the new technology of Oí brand HERO presents a very high rejection of all pollutants, especially of weak acid anions. In addition, a recovery of ninety percent (90%) or greater can be obtained with almost all the feed waters. Biological contamination is essentially eliminated while particulate contamination is substantially reduced. With the new HERO technology, a much higher flow than that obtained with the conventional Oi system can be achieved. Although the benefits of this new process could justify a higher cost of the UPW system, just the opposite happens. The overall cost, as well as the complexity of the UPW system are drastically reduced. The method and device for processing water by means of membrane separation equipment and especially by the HERO brand reverse osmosis process design described here, provides a revolutionary and paradoxical result, mainly a simultaneous increase of silica levels in the rejection of I heard it, but with lower levels of silica in the purified infiltrate of the Oi. This method of operation with membrane separation systems, and in particular, to operate reverse osmosis systems, represents an important option for reducing water consumption while also reducing the capital and operating costs of the water treatment system. The water recovery, that is, the ratio between the amount of the product stream of the infiltrate produced to the amount of the feedwater stream provided is obviously more than 50%, and will easily rise up to 85% or more, and often will be of levels up to approximately 95%, and will sometimes reach levels of around 99%). Thus, given the efficiencies, there will be a much lower consumption of chemical reagents, either for ion exchange regenerant or for cleaning the Oi, per gallon of pure water produced.

Therefore, it will be noted that the objectives established above, including those that emerged from the description of the procedure, are achieved efficiently and, as certain changes can be made for the development of the described method and for the construction of a suitable device for developing the method and producing the desired product according to what is established herein, it is understood that the invention can be carried out in other specific modalities without deviating from the spirit or essential characteristics thereof. For example, although I have established an exemplary design for the simultaneous removal of hardness and alkalinity, other modalities are also feasible to achieve the result of the principles of the method presented in this document. Therefore, it is to be understood that the foregoing description of the representative embodiments of the invention have been presented solely for the purpose of illustrating and providing an understanding of the invention, and it is not an exhaustive and limiting description, which limits the invention to the forms accurate presented. On the contrary, the intention is to cover all the modifications, equivalents and alternatives that fall within the inventive spirit and scope as expressed in the appended claims. As such, the claims are intended to include the methods and structures described therein and not only the equivalents or structural equivalents thereof, but also the equivalent structures and methods. Thus, the scope of the invention, as indicated in the appended claims, is intended to include the variations of the indicated modalities, which are described by the broad meaning and range that conform to the language of the claims, or to their equivalents.

Claims (120)

1. Novelty of the Invention 1. A process for the treatment of a feedwater stream in membrane separation equipment, said membrane separation equipment comprising at least one unit having a membrane separator, to produce a product stream that it has a low content of solute, and a reject current that has a high content of solute, said process comprising: (a) providing a stream of feed water containing solutes, said solutes comprising: (i) hardness; (ii) alkalinity; and (iii) at least one molecular species that is sparingly ionized when it is in aqueous solution at a neutral or near neutral pH; (b) concentrating said feed stream in a first unit of said membrane separation equipment after reducing the tendency of said feed water to form scale when said feed water is concentrated to a pre-selected concentration factor at a given pH performing, in any order, one of the following operations: (i) eliminate the hardness of said feed water; (ii) substantially removing all alkalinity associated with the hardness of said feed water stream; and (iii) removing dissolved gas from said feed water stream, whether initially present or created during the step of removing said hardness or said alkalinity; (c) raising the pH of the product from step (a) to a selected pH to at least 8.5 to induce said at least one molecular species that is sparingly ionized when it is in aqueous solution at a neutral or near neutral pH, towards an increased ionization; (d) passing the product of step (c) through said membrane separation equipment, said membrane separation equipment substantially resisting the passage of dissolved species therethrough, to concentrate said feedwater to said factor of pre-selected concentration, to produce: (i) a reject current possessing a high solute content; Y; (ii) a product stream possessing a low solute content.
2. 2. A process for the treatment of a feedwater stream in membrane separation equipment, said membrane separation equipment comprising at least one unit having a membrane separator, to produce a product stream having a low content of solute, and a reject current having a high content of solute, said process comprising: (a) providing a stream of feed water containing solutes, said solutes comprising: (i) hardness; (ii) alkalinity; and (iii) at least one molecular species that is sparingly ionized when it is in aqueous solution at a neutral or near neutral pH; (b) concentrating said feed stream in a first unit of said membrane separation equipment after effectively eliminating the tendency of said feed water to form scale when said feed water is concentrated at a pre-selected concentration factor to a pH determined, performing, in any order, one of the following operations: (i) eliminate the hardness of said feed water stream; (ii) substantially remove from said feedwater stream all alkalinity that is not due to hydroxides; and (iii) eliminating dissolved gases, whether initially present or created during the removal stage of said hardness or said alkalinity; (c) raising the pH of the product of step (a) to a selected pH of at least about 8.5 by adding a selected base thereto, to induce said at least one molecular species that is sparingly ionized when it is found in aqueous solution at a neutral or almost neutral pH, towards an increased ionization; (d) passing the product of step (c) through said membrane separation equipment to produce a reject stream and product stream, said membrane separation equipment substantially resisting the passage of dissolved species through it, to concentrate said feed water to said pre-selected concentration factor, to produce: (i) a reject current possessing a high content of solute; Y; (ii) a stream of infiltrated product possessing a low solute content.
3. 3. The process as set forth in claim 1, wherein the steps of (a) hardness removal, and (b) substantial removal of all alkalinity associated with hardness, are carried out in a single unit operation .
4. 4. The process as set forth in claim 3, wherein said single unit operation comprises a weak acid cation ion exchange system.
5. 5. The process as set forth in claim 4, wherein said weak acid cation ion exchange system is operated in the hydrogen form.
6. 6. The process as set forth in claim 4, wherein said weak acid cation ion exchange system is operated in the sodium form. The process as set forth in claim 1 or 2, wherein the step of removing the hardness is carried out by passing said feed water through a strong acid cation ion exchange system in the sodium form. 8. The process as set forth in claim 1 or 2, wherein in step (c) the pH is raised to between 9 and 10. The process as set forth in claim 1 or 2, wherein in the step (c) the pH is raised to between 10 and 11. The process as set forth in claim 9, wherein in the pH is controlled at about 10.5. 11. The process as set forth in claim 1 or 2, wherein in the step (c) the pH is raised to at least about 11. The process as set forth in claim 1 or 2, wherein in step (c) the pH is raised to at least about 12. 13. The process as set forth in claim 1 or 2, wherein at least one sparingly ionized species when in an aqueous solution at a neutral or near neutral pH comprises Si02. The process as set forth in claim 1 or 2, wherein said at least one sparingly ionized species when in an aqueous solution at a neutral or near neutral pH comprises meta / ortho silicic acid (H SiO). 15. The process as set forth in claim 1 or 2, wherein said at least one sparingly ionized species when in aqueous solution at a neutral or near neutral pH includes boron. 16. The process as set forth in claim 1 or 2, wherein said at least one sparingly ionized species when in an aqueous solution at a neutral or near neutral pH comprises orthoboric acid (H3BO3). The process as set forth in claim 1 or 2, wherein said at least one sparingly ionized species when in an aqueous solution at a neutral or near neutral pH comprises a species of ionizable organic carbon. 18. The process as set forth in claim 1 or 2, wherein said at least one sparingly ionized species when in an aqueous solution at a neutral or near neutral pH comprises a species of organic carbon that can be converted into a proton. 19. The process as set forth in claim 1 or 2, wherein said at least one sparingly ionized species when in aqueous solution at a neutral or near neutral pH comprises humic acid or its derivatives. The process as set forth in claim 1 or 2, wherein said at least one sparingly ionized species when in an aqueous solution at a neutral or near neutral pH comprises fulvic acid or its derivatives. 21. The process as set forth in claim 1 or 2, wherein said at least one sparingly ionized species when in an aqueous solution at a neutral or near neutral pH comprises silica above about 120 ppm. 22. The process as set forth in claim 1 or 2, wherein said at least one sparingly ionized species when in aqueous solution at a neutral or quasi-neutral pH comprises silica, and wherein said reject stream having a high content of solute contains silica above about 160 ppm. 23. The process as set forth in claim 22, wherein the silica is present in said reject stream having a high solute content in up to about 450 ppm. 24. The process as set forth in claim 22, wherein the silica is present in the reject stream having a high solute content in excess of about 500 ppm. 25. The process as set forth in claim 22, wherein the silica is present in said reject stream having a high solute content in up to about 500 ppm. 26. The process as set forth in claim 22, wherein the silica is present in said reject stream having a high solute content in up to about 1000 ppm. 27. The process as set forth in claim 1 or 2, wherein the stream of the feed water includes silica, and wherein the membrane separation equipment operates without limit of the concentration of the silica present in said reject stream having a high solute content 28. The process as set forth in claim 1 or 2, wherein the reject current includes about 100,000 ppm of TDS. 29. The process as set forth in claim 10, wherein the species barely ionized in aqueous solution of neutral or quasi-neutral pH includes cyanide. 30. The process as set forth in claim 29, wherein the reject stream having high solute content contains about ninety percent (90%) of cyanide present in said stream of feedwater. 31. The process as set forth in claim 29, wherein said reject stream having a high solute content contains about ninety-nine percent (99%) of cyanide present in said stream of feed water. 32. The process as set forth in claim 10, wherein the species barely ionized when in an aqueous solution of neutral or quasi-neutral pH, includes a weak acid with a pKai of about 7.5 or greater. The process as set forth in claim 2, wherein the feedwater stream further comprises live bacteria, and wherein the step of raising the pH exterminates the living bacteria present so that the product stream is essentially free of bacteria. 34. The process as set forth in claim 33, wherein the step of raising the pH, killing the living bacteria, producing fragments of bacteria and endotoxins, and wherein said process also destroys said bacterial fragments and endotoxins, for provide a product stream essentially free of bacteria and endotoxins. 35. The process as set forth in claim 1 or 2, wherein the supply water stream further comprises live viruses, and wherein the pH raising step exterminates the live viruses present, so that the product stream is essentially free. of live viruses. 36. The process as set forth in claim 1 or 2, wherein the ratio between the amount of product stream produced and the amount of feed stream supplied is greater than about 50%. 37. The process as set forth in claim 1 or 2, wherein the ratio between the amount of product stream of the infiltrate produced and the amount of feed stream supplied is about 85% or more. 38. The process as set forth in claim 1 or 2, wherein the ratio between the amount of product stream of the infiltrate produced and the amount of feed stream supplied is about 95% or more. 39. The process as set forth in claim 1 or 2, wherein the ratio between the amount of product stream of the infiltrate produced and the amount of feed stream supplied is about 99% or more. 40. The process according to claim 1 or 2, wherein the membrane separation equipment comprises nanofiltration equipment. 41. The process according to claim 1 or 2, wherein the membrane separation equipment comprises reverse osmosis equipment. 42. The process according to claim 41, wherein the reverse osmosis equipment comprises N units of reverse osmosis operated in series of units from 1 to N, with respect to the product stream, and wherein N is a positive integer. 43. The process according to claim 41, further comprising the step of passing said product water stream from the reverse osmosis equipment through at least one primary mixed bed ion exchange unit and a bed ion exchange unit. mixed secondary 44. The process according to claim 43, further comprising the step of running the primary mixed-bed ion exchange unit at a preselected leakage rate with respect to one or more of the following (a) silica, (b) boron, or (c) TOC, discarding the resin from the media of said primary mixed-bed ion exchange unit, and thus replacing the means of the secondary mixed-bed ion exchange unit. 45. The process according to claim 43, wherein the primary mixed bed ion exchange unit is not regenerated for reuse in said process. 46. The process according to claim 1 or 2, wherein the step of raising the pH is performed by adding a base in aqueous solution, said base being selected from the group consisting of (a) sodium hydroxide, (b) sodium carbonate, (c) potassium hydroxide and (d) potassium carbonate. 47. The process according to claim 1 or 2, wherein the step of raising the pH is carried out by adding an aqueous organic base. 48. The process according to claim 1 or 2, wherein the step of raising the pH is carried out using an anion ion exchanger to raise the number of hydroxide ions present in the feed water stream. 49. The process according to claim 1 or 2, wherein the feed water comprises the purging of a cooling tower. 50. The process according to claim 1 or 2, wherein the feed water comprises the purge of scrubbers. 51. The process according to claim 1 or 2, wherein the feed water comprises water used in the transport of ash in a coal-driven thermoelectric plant. 52. The process according to claim 1 or 2, wherein said product stream of said process comprises a boron content of less than about two percent (2%) of the boron content of said feed water stream. 53. The process of claim 1 or 2, wherein said product stream from said process comprises a boron content of about one and a half percent (1.5%), or less, of the boron content of said water stream of feeding. 54. The process of claim 1 or 2, wherein said product stream from said process comprises a boron content of about one percent (1%), or less, of the boron content of said feed water stream. 55. The process of claim 1 or 2, wherein said product stream from said process comprises a silica content of less than about 0.05% silica content of said feed water stream. 56. The process of claim 1 or 2. wherein said product stream from said process comprises essentially zero bacterial content. 57. The process of claim 1 or 2, wherein said product stream of said process comprises essentially zero live viruses therein. 58. A device for the treatment of a feed water stream, said feed water stream characterized by the presence of (i) hardness, (ii) alkalinity and (iii) at least one molecular species barely ionized when it is found. in aqueous solution of neutral or almost neutral pH, to produce a product stream that has a low content of solute and a reject current that has a high content of solute, said apparatus comprises in order for the flow of feed water: (a ) pretreatment equipment to effectively eliminate the tendency of the feed water to form scale when said feed water is concentrated to a desired concentration factor, at a selected pH, comprising, in any order, two or more of the following: ( i) at least one softener to remove substantially all of the hardness of the feedwater stream; (ii) at least one de-alkalizer to remove substantially all of the alkalinity associated with the hardness of the feedwater stream; (iii) a degasser to remove at least some dissolved gases, whether initially present or created during the removal of said hardness or said alkalinity; (b) chemical addition apparatus for raising the pH of the product of step (a) to a selected pH of at least about 8.5 by adding a selected base, to induce at least said molecular species barely ionized in aqueous solution of Neutral or almost neutral pH, towards an increased ionization; (c) one or more reverse osmosis membrane units, said one or more reverse osmosis membrane units for treating the feed water to produce a reject stream and a product stream; said one or more reverse osmosis membrane units substantially resisting the passage of ionized species, to concentrate said feed water to said preselected concentration factor. 59. The device as claimed in claim 58, wherein said one or more reverse osmosis membrane units works in series with respect to said product stream of said one or more reverse osmosis membrane units, and wherein said one or more units of reverse osmosis membrane comprises N units of reverse osmosis membrane in a series of units from 1 to N, and wherein N is a positive integer greater than 1. 60. The device as claimed in claim 59, further comprising downstream of an N-reverse reverse osmosis membrane unit, to further process the product stream, a primary mixed-bed ion exchange unit and a secondary mixed-bed ion exchange unit. 61. The device as claimed in claim 60, further comprising a final micron filter. 62. The device as claimed in claim 60, further comprising an ultraviolet sterilization unit. 63. The process as claimed in claim 42, further comprising the step of treating the product stream in a continuous electrodeionization unit to produce a stream of purified water. 64. The process as claimed in claim 63, further comprising the step of purifying said stream of purified water exiting the continuous electrodeionization unit in an ultraviolet sterilization unit. 65. The process as claimed in claim 64, further comprising the step of purifying the product stream from the ultraviolet sterilization unit in a final filter of less than one miera to produce ultrapure water product. 66. The process as claimed in claim 63, further comprising the step of treating said stream of purified water in a mixed-bed ion exchange system. 67. The process as claimed in claim 65, wherein the ultrapure water product meets or exceeds the standard resistivity standard of 18.2 megohms. 68. A method for simultaneously increasing the production of infiltrate (flow) and its purity in an existing reverse osmosis system that treats a feedwater stream in at least one unit of the reverse osmosis system to produce a product stream having a low solute content and a reject stream having a high content of solute, said method comprising (a) supplying a stream of feed water containing solutes, said solutes comprising: (i) hardness; (ii) alkalinity; and (iii) at least one molecular species that is sparingly ionized when it is in aqueous solution at a neutral or near neutral pH; (b) concentrating said feed stream in a first of said at least one reverse osmosis unit after reducing the tendency of said feed water to form scale when said feed water is concentrated at a pre-selected concentration factor to a pH determined, performing, in any order, one of the following operations: (i) eliminate the hardness of said feed water stream; (ii) substantially removing all alkalinity associated with the hardness of said feed water stream; and (iii) removing dissolved carbon dioxide from said feed water stream, whether initially present or created during the step of removing said hardness or said alkalinity; (c) raising the pH of the product of step (a) to a selected pH of at least 8.5, to induce said at least one molecular species that is sparingly ionized when it is in aqueous solution at a neutral or near neutral pH , towards an increased ionization; (d) passing the product of step (c) through said reverse osmosis system, said reverse osmosis system of the type that substantially resists the passage of dissolved species therethrough, to concentrate said feed water to said pre-selected concentration factor, to produce: (i) a reject current possessing a high solute content; Y; (ii) a product stream possessing a low solute content, and (iii) producing said product stream at a production (flow) ratio of at least about 20 gallons per square foot per day. 69. A method for simultaneously increasing the production of infiltrate (flow) and purity thereof in an existing membrane separation system that treats a feedwater stream in at least one membrane separation system that produces a current product having a low solute content and a reject stream having a high content of solute, said method comprising (a) providing a stream of feed water containing solutes, said solutes comprising: (i) hardness; (ii) alkalinity; and (iii) at least one molecular species that is sparingly ionized when it is in aqueous solution at a neutral or near neutral pH; (b) concentrating said feed stream in a first of said membrane separation system after effectively reducing the tendency of said feed water to form scale when said feed water is concentrated to a pre-selected concentration factor at a pH determined, performing, in any order, one of the following operations: (i) eliminating an effective amount of hardness from said feed water stream; (ii) removing an effective amount of alkalinity from said feed water stream; and (iii) removing dissolved gases, whether initially present or created during the removal stage of said hardness or said alkalinity; (c) raising the pH of the product of step (a) to a selected pH of at least about 8.5, by the addition of a selected base, to induce said at least one molecular species that is poorly ionized when it is present in aqueous solution at a neutral or almost neutral pH, towards an increased ionization; (d) passing the product of step (c) through said membrane separation system, to produce a reject current and a product stream, said membrane separation equipment of the type which substantially resists the passage of species dissolved through it, to concentrate said feed water to said pre-selected concentration factor, to produce: (i) a reject stream possessing a high content of solute; and (ii) a product stream possessing a low solute content, and (iii) producing said product stream at a production (flow) ratio of at least about 20 gallons per square foot per day. 70. The method as set forth in claim 68 or 69, wherein the steps of (a) removing hardness, and (b) removing alkalinity, are carried out in a single-unit operation. 71. The method as set forth in claim 70, wherein said operation of a single unit comprises a weak acid cation ion exchange system. 72. The method as set forth in claim 71, wherein said weak acid cation ion exchange system is operated in the hydrogen form. 73. The method as set forth in claim 71, wherein said weak acid cation ion exchange system is operated in the sodium form. 74. The method as set forth in claim 69, wherein in step (c) the pH is raised to between 9 and 10. 75. The method as set forth in claim 68 or 69, wherein in the step ( c) the pH is raised to between 10 and 11. 76. The method as set forth in claim 75, wherein the pH is controlled at about 10.5. 77. The method as set forth in claim 69, wherein in step (c) the pH is raised to at least about 11. 78. A method to simultaneously provide high infiltrate production. (flow) and high purity of infiltrate in a reverse osmosis system that treats a feedwater stream, to produce a product stream that has a low solute content and a reject stream that has a high solute content, said method comprising (a) providing a stream of feed water containing solutes, said solutes comprising: (i) hardness; (ii) alkalinity; and (iii) at least one molecular species that is sparingly ionized when it is in aqueous solution at a neutral or near neutral pH; (b) before introducing said feed water stream into said reverse osmosis system, reducing the tendency of said feed water to form scale when said feed water is concentrated to a pre-selected concentration factor at a given pH , performing, in any order, one or more of the following operations: (i) eliminating the hardness of said feed water stream; (ii) substantially removing all alkalinity, not due to hydroxide, from said feed water stream; and (iii) removing carbon dioxide from said feed water stream, whether initially present or created during the step of removing said hardness or said alkalinity; (c) raising the pH of the product of step (b) to a selected pH of at least about 8.5, to induce said at least one molecular species that is sparingly ionized when it is in aqueous solution at a neutral or near pH neutral, towards an increased ionization; (d) passing the product of step (c) through said reverse osmosis system, said reverse osmosis system substantially resisting the passage of dissolved species therethrough, to concentrate said feedwater to said concentration factor pre-selected, while working said reverse osmosis system at a flow above 15 gallons per square foot per day, to produce: (i) a reject current possessing a high solute content; Y; (ii) a product stream possessing a low solute content. 79. A process for treating a feedwater stream in a membrane separation equipment comprising at least one unit having a membrane separator to produce a product stream having a low solute content, and a reject stream having a high content of solute, said process comprising: (a) providing a stream of feed water containing solutes, said solutes comprising: (i) hardness; (ii) alkalinity; and (iii) at least one molecular species that is sparingly ionized when it is in aqueous solution at a neutral or near neutral pH; (b) concentrating said feed stream in a first unit of said membrane separation equipment after reducing the tendency of said feed water to form scale when said feed water is concentrated to a pre-selected concentration factor at a pH determined, performing, in any order, two or more of the following operations: (i) removing an effective amount of hardness from said feed water stream; (ii) substantially eliminating from said feed water stream all the alkalinity associated with the hardness; and (iii) removing the gas from said feed water stream, whether initially present or created during the step of removing said hardness or said alkalinity; (c) raising the pH of the product of step (b) to a selected pH of at least about 8.5 to induce said at least one molecular species that is sparingly ionized when it is in aqueous solution at a neutral or near neutral pH , towards an increased ionization; (d) passing the product of step (c) through said separation equipment through, said membrane separation equipment substantially resisting the passage of dissolved species therethrough, to concentrate said feed water to said pre-selected concentration factor. 80. The process as claimed in claim 1, 2, 68 or 69, wherein said product stream is substantially free of said at least one molecular species that is sparingly ionized when it is in aqueous solution at a neutral or near neutral pH. . 81. The device as claimed in claim 58, wherein said product stream is substantially free of said at least one molecular species that is sparingly ionized when it is in an aqueous solution at a neutral or near neutral pH. 82. The process of claim 78, wherein said flow of said reverse osmosis membrane is at least about 20 gfd. 83. The process of claim 68, 69 or 78, wherein said flow of said reverse osmosis membrane is at least about 24 gfd. 84. The process of claim 68, 69 or 78, wherein said flow of said reverse osmosis membrane is at least about 30 gfd. 85. In a process for purifying an aqueous solution by passing a portion of said aqueous solution through a semi-permeable membrane in membrane separation equipment to produce a product stream, and retaining at least a portion of said product. aqueous solution in said membrane separation equipment to increase the concentration of a solute to a predetermined concentration factor in said retained portion of said aqueous solution, the improvement comprising feeding said membrane separation equipment with a characterized aqueous solution, moment of initial entry into the membrane separation equipment, by comprising (a) substantially no hardness, (b) substantially no alkalinity associated with hardness, (c) substantially no dissolved or suspended carbon dioxide, and (d) a pH of at least about 8.5. 86. In a process for the purification of an aqueous solution comprising solutes and solvent by passing a portion of said aqueous solution through a semi-permeable membrane into at least one unit of membrane separation equipment to produce a product stream, and retaining at least a portion of said aqueous solution in a first unit of said at least one unit of membrane separation equipment for increasing the concentration of a pre-selected solute to a predetermined concentration factor in said retained portion of said aqueous solution. , the improvement comprising controlling the solutes in said aqueous solution to a level where the tendency to form scale is effectively eliminated at said preselected concentration factor, by (a) before feeding said aqueous solution to said first unit of said one or more units of membrane separation equipment; (i) reducing the hardness of said aqueous solution, (ii) reducing the alkalinity of said aqueous (fed) solution, (iii) reducing the carbon dioxide contained therein, and (b) after step (a), increasing the pH of said aqueous-fed solution to at least 8.5. 87. In a process for the production of high purity water from a municipal water supply through membrane separation equipment, said municipal water supply by providing an aqueous solution comprising solutes and water, and wherein a part of said aqueous solution is passed through a semipermeable membrane in a first unit of membrane separation equipment to produce a product stream, and wherein at least a portion of said aqueous solution is retained in said first unit of separation equipment by membrane for increasing the concentration of a preselected solute to a predetermined concentration factor, the improvement comprising feeding said first unit of membrane separation equipment with a stream of municipal water that has been further treated to generate an aqueous solution by (a ) before feeding said aqueous solution to said membrane separation equipment; (i) essentially reducing all hardness, (ii) essentially reducing all alkalinity not due to hydroxide, (iii) substantially reducing all dissolved carbon dioxide, and (b) increasing the pH to at least 8.5. 88. The improvement according to claim 78, 85, 86 or 87, wherein said aqueous feed solution is further characterized by the lack of the addition of an scale inhibiting solution to said aqueous fed solution. 89. The improvement according to claim 78, 79, 85, 86 or 87, wherein said membrane separation equipment comprises reverse osmosis equipment. 90. The improvement according to claim 78, 79, 85, 86 or 87, wherein said membrane separation equipment produces a product stream characterized by meeting or exceeding the resistivity quality standard of 18 megohm. 91. In a process for the purification of an aqueous solution comprising solutes and solvent by the use of membrane separation equipment to increase the concentration of said solution to a preselected concentration factor by passing a portion of said aqueous solution to through a semi-permeable membrane in a first unit of said membrane separation equipment to produce a product stream, and to retain at least a portion of said aqueous solution in said first unit of said membrane separation equipment to increase the concentration of a pre-selected solute at a predetermined concentration factor in said retained portion of said aqueous solution, the improvement comprising controlling the solutes, hardness, alkalinity and carbon dioxide in said aqueous solution at a level where the tendency to form scale is effectively eliminated from said pre-selected concentration factor, by (a) before feeding said aqueous solution to said first unit of said membrane separation equipment, optionally and in any order: (i) reducing the hardness of said aqueous feed solution (ii) reducing the alkalinity of said solution of aqueous feed, (iii) reducing dissolved or suspended carbon dioxide there, and (b) then, after step (a), increasing the pH of said aqueous feed solution to at least 8.5. 92. Water produced according to the process of claim 1, wherein said water is the product stream of said process, said stream of feed water comprising boron, and wherein said product stream is characterized in that it has a boron content of less than about two percent (2%) of the boron content of the feedwater stream. 93. Water produced in accordance with the process of claim 1, wherein said water is the product stream of said process, said stream of feed water further comprising boron, and wherein said product stream is characterized by having a boron content. about one and a half percent (1.5%), or less, of the boron content of the feedwater stream. 94. Water produced in accordance with the process of claim 1, wherein said water is the product stream of said process said feed water stream further comprising boron, and wherein the product stream is characterized in that it has a boron content of around one percent (1%). or less, the boron content of the feedwater stream. 95. Water produced in accordance with the process of claim 1, wherein said water is the product stream of said process said feed water stream further comprises silica, and wherein said product stream is characterized in that it has a silica content of less than about 0.05% of the silica content of the feedwater stream. 96. Water produced in accordance with the process of claim 1, wherein said water is the product stream of said process said feed water stream further comprises bacteria, and wherein said product stream is characterized in that it has a content of bacteria essentially null. 97. Water produced in accordance with the process of claim 1, wherein said water is the product stream of said process, said feed water stream further comprising live viruses, and wherein said product stream is characterized in that it has essentially zero live viruses. . 98. The process as claimed in claim 42, wherein after said N-reverse reverse osmosis unit, said product stream is additionally treated in a cation exchange unit. 99. The process as claimed in claim 42, further comprising the step of passing said product stream from said reverse osmosis equipment through at least one mixed-bed ion exchange unit. 100. The device as claimed in claim 58, further comprising, downstream of the N-reverse reverse osmosis membrane unit, at least one mixed-bed ion exchange unit for processing the product stream from said N-eima reverse osmosis unit. 101. The process as claimed in claim 1, 2, 68, 69, 78, 79, 86 or 91, further comprising, during the alkalinity removal step, the additional step substantially eliminating all alkalinity that should not be to hydroxide that is not associated with hardness. 102. The process as set forth in any one of claims 78, 79, 85, 86, 87 or 91, wherein during the step of raising the pH of said feed water, the pH is raised to between about 9 and about 10. 103. The process as set forth in any one of the claims 78, 79, 85, 86, 87 or 91, wherein during the step of raising the pH of said feed water, the pH rises to between about 10 and about 1 1. 104. The process as set forth in any one of of claims 78, 79, 85, 86, 87 or 91, wherein the step of raising the pH comprises controlling the pH to about 10.5. 105. The process as set forth in any one of claims 78, 79, 85, 86, 87 or 91, wherein after the step of raising the pH of said feed water, the pH of said feed water rises. at least about 1 1. The process as set forth in any one of claims 1, 2, 69, 79, 85, 86, 87 or 91, wherein said membrane separation equipment comprises a membrane composed of a film. thin. 107. The process as set forth in claim 89, wherein said reverse osmosis equipment comprises a thin film composite membrane. 108. A process for the treatment of a feedwater stream in membrane separation equipment, said membrane separation equipment comprising at least one unit having a membrane separator, to produce a product stream having a low content. of solute, and a reject current having a high content of solute, said process comprising: (a) providing a stream of feed water containing solutes, said solutes comprising: (i) hardness; (ii) alkalinity; and (iii) at least one molecular species that is sparingly ionized when it is in aqueous solution at a neutral or near neutral pH; (b) concentrating said feed water stream in a first unit of said membrane separation equipment, after effectively reducing the tendency of said feed water to form scale when said feed water is concentrated at a preselected concentration factor to a certain pH, performing: (i) removing an effective amount of hardness from said feed water stream; (ii) removing an effective amount of alkalinity associated with the hardness of said feed water stream; (iii) removing an effective amount of dissolved gas from said feed water stream, whether initially present or created during the step of removing said hardness or said alkalinity; (c) raising the pH of the product of step (a) to a selected pH to at least about 8.5 to induce said at least one molecular species that is sparingly ionized when it is in aqueous solution at a neutral or near neutral pH , towards an increased ionization; (d) passing the product of step (c) through said membrane separation equipment, said membrane separation equipment substantially resisting the passage of dissolved species therethrough, to concentrate said feedwater to said factor of pre-selected concentration, to produce: (i) a reject current possessing a high solute content; Y; (ii) a product stream possessing a low solute content. 109. A process for the treatment of a feed water stream in a reverse osmosis system, said reverse osmosis system comprising at least one unit comprising a membrane separator, to produce a product stream having a low content of solute. , and a reject current having a high content of solute, said process comprising: (a) providing a stream of feed water containing solutes, said solutes comprising: (i) hardness; (ii) alkalinity; and (iii) at least one molecular species that is sparingly ionized when it is in aqueous solution at a neutral or near neutral pH; (b) concentrating said feed stream in a first unit of said reverse osmosis system after effectively eliminating the tendency of said feed water to form scale when said feed water is concentrated to a pre-selected concentration factor at a pH determined, performing: (i) removing an effective amount of hardness from said feed water; (ii) removing an effective amount of alkalinity associated with the hardness of said feed water stream; (c) raising the pH of the product of step (a) to a selected pH to at least about 10.0 to induce said at least one molecular species that is sparingly ionized when it is in aqueous solution at a neutral or near neutral pH , towards an increased ionization; (d) passing the product of step (c) through said reverse osmosis system, said reverse osmosis system substantially resisting the passage of dissolved species therethrough, to concentrate said feedwater to said concentration factor pre-selected, to produce: (i) a reject current possessing a high solute content; Y; (ii) a product stream possessing a low solute content. 110. A process for the treatment of a feedwater stream in a membrane separation system, said membrane separation system comprising at least one unit having a membrane separator, to produce a product stream having a low content of solute, and a reject current having a high content of solute, said process comprising: (a) providing a stream of feed water containing solutes, said solutes comprising: (i) hardness; (ii) alkalinity; and (iii) at least one molecular species that is sparingly ionized when it is in aqueous solution at a neutral or near neutral pH; (b) concentrating said feed water stream in a first unit of said membrane separation system after effectively eliminating the tendency of said feed water to form scale when said feed water is concentrated at a preselected concentration factor to a pH determined, performing: (i) removing an effective amount of hardness from said feed water stream; (ii) removing an effective amount of alkalinity associated with the hardness of said feed water stream; (c) raising the pH of the product of step (b) to a selected pH to at least about 10.0 to induce said at least one molecular species that is sparingly ionized when it is in aqueous solution at a neutral or near neutral pH , towards an increased ionization; (d) passing the product of step (c) through said membrane separation equipment, said membrane separation equipment substantially resisting the passage of dissolved species through cl, to concentrate said feed water to said factor of pre-selected concentration, to produce: (i) a reject current possessing a high content of solute; Y; (ii) a product stream possessing a low solute content. 111. The process as claimed in claim 4, wherein said feed water stream contains more hardness than alkalinity, further comprising, before feeding said feed water to said weak acid cation exchange system, the step of adjusting the hardness to alkalinity ratio by adding a base to said feed water, in order to raise the alkalinity of said feed water. 112. The process as claimed in claim 4, wherein said feed water stream contains more hardness than alkalinity, further comprising, before feeding said feed water to said weak acid cation exchange system, the step of adding acid to said feed water, to destroy the excess alkalinity of said feed water. 113. The process as claimed in claim 6, further comprising the step of adding acid prior to the step of removing the dissolved gas, to effect the conversion of alkalinity to carbon dioxide. 114. The process as claimed in claim 1 or 2, wherein in step (c), the pH is raised to more than about 12, as determined in the reject stream. 115. The process as claimed in claim 1 or 2, wherein in step (c), the pH is raised to more than about 13, as determined in the reject stream. 116. The process as claimed in claim 1 or 2, wherein the ratio of the amount of said infiltrated product stream produced to the amount of said feedwater stream provided is between 90 and 98 percent. 117. The process as claimed in claim 1 or 2, wherein said feed water further comprises chlorine. 118. The process as claimed in claim 1 or 2, wherein the step of removing said dissolved gas comprises the step of passing said feed water through a gas-permeable membrane barrier. 119. The process as claimed in claim 1, 2, 69, 79, 85, 86, 87 or 91, wherein said feed water further comprises silica, and wherein said membrane separation equipment is operated at differential pressure. , and wherein said process is further characterized by (a) a stable normalized ratio of infiltrate production; (b) a stable differential pressure. 120. The process as claimed in claim 68, 69 or 78, wherein said flow of said reverse osmosis membrane is between about 30 gallons per square foot per day and about 50 gallons per square foot per day.