[001] The present invention relates to the field of water purifier. The present invention more particularly relates to a system and method of adjusting the pH of reverse osmosis (RO) membrane permeate water in a point of use (POU) water treatment system.
BACKGROUND AND PRIOR ART AND PROBLEM IN PRIOR ART:
[002] Reverse Osmosis is one of the widely used technology nowadays to purify the polluted water. This can remove the dissolved chemicals including the hazardous heavy metals ions, pesticides and viruses, bacteria, cysts from the polluted water. The total dissolved solid reduction by a Reserve Osmosis membrane varies from 90 to 97%.
[003] When the water passes through a Reverse Osmosis membrane, the dissolved solids and microbes are separated but the dissolved gases passes through the membrane along with the purified water. The magnitude of reduction of dissolved solids by RO membrane also varies significantly.
[004] In other words, when water passed through a reverse osmosis (RO) membrane it disturbs the equilibrium between carbonates, bicarbonates and carbon dioxide. The difference in magnitude of rejection of carbonates> bicarbonates> carbon dioxide, results in upsetting the CO3, HCO3, CO2 equilibrium that was established in the feed. In a series of equilibrium reactions, CO2 will combine with H2O driving reactions similar to that shown below, until a new equilibrium is established.
CO2 + H2O —► HCO3 + H+
[005] The new equilibrium may result in a lowering of permeate pH if there is CO2 gas present in the feed water. The pH drop is usually largest for waters with high amounts of alkalinity or HCO3.
[006] The drop in pH imparts a bitter/objectionable taste to purified water.

[007] Publication No. KR20020093663 discloses the reverse osmotic membrane water purifier comprises a filter(ll) for filtering solids contained in raw water; a pre carbon filter(12) and a post carbon filter(13) which are consisted of activated carbon for adsorbing and thus removing harmful substances contained in purified water obtained from the filter(ll); a reverse osmosis filter(14) which is installed at the downstream of the pre carbon filter(12) and the post carbon filter(13); an ultraviolet ray sterilizing tank(16) and an ozone sterilizing tank(17) which are installed at the downstream of the reverse osmosis filter(14); a post treatment filter(18) which is arranged at the downstream of the sterilizing tanks(16,17) to remove unpleasant taste and smell from pure water obtained from the sterilizing tanks(16,17); a pure water storage reservoir(19) which is arranged at the downstream of the post treatment filter(18); and a concentrated water regeneration tank(24) which is arranged on a branch pipe that is branched from the reverse osmosis filter(14) to recirculate water to the filter(l 1).
[008] Publication No. US6056989 discloses pH adjustor for drinks comprising a potassium salt as an active ingredient wherein said potassium salt comprises an effective amount for adjusting pH of at least two members selected from the group consisting of potassium carbonate, dipotassium hydrogen phosphate and potassium hydroxide, whereby the pH adjustor is capable of suppressing the deterioration of aroma and/or taste due to lowering of pH by retort sterilization.
[009] Publication No. CN206872552 discloses an efficient reverse osmosis water purifier, which is equipped with the reverse osmosis cavity body, filters cavity and water storage bucket, and reverse osmosis cavity is internal to be equipped with water purification portion and to go out water portion, separate through reverse osmosis membrane between water purification portion and the play water portion, be equipped with the water purification piston in the water purification portion, the water purification piston is external to have peripheral hardware dynamic mechanism driving, be equipped with the into water inlet control valve of water of being convenient for on the water purification piston, water inlet control valve's the logical pipe of import is connected with the delivery

port that filters the cavity, the bottom of water purification portion still is equipped with the waste water discharge port, and waste water discharge port department is equipped with the drainage control valve of control waste water discharge port switching, be equipped with the delivery port on going out water portion, the delivery port leads to pipe to be connected with the water storage bucket.
[0010] Publication No. 972/DEL/2013 discloses an alkaline mineral cartridge, which can improve the quality of water purified by Reverse Osmosis (RO) based domestic water purifier by adding essential minerals required for human health, make acidic RO purified water alkaline and enhances the taste of RO purified water.
[0011] Publication No. 2369/CHE/2012 discloses potable water plus technology is the mechanism which helps to maintain the proper mineral level in the Reverse Osmosis process based purifier output drinking water. This new technology comprises a "Mineral Maintainer & Mineral Monitor" in the water purifier. Mineral maintainer is the switch which helps to maintain the proper minerals (pH & TDS) level in the output water. This monitor displays the actual level of pH & TDS in the treated output water as well as feed water TDS. If the mineral level is to be low, it will display in the mineral monitor and the user can increase the minerals and make water as a potable one or if the minerals level (pH & IDS) is to be high, the user can reduce the mineral level and make water as a potable one.
[0012] Publication No. 725/MUM/2012 discloses a household nanofiltration (NF) membrane based water purifier for producing or generating pure drinking water, wherein by using a nanofiltration (NF) membrane (or nanofiltration membrane module) with specific characteristics it is possible to partially remove divalent cations and monovalent ions present in the feed water, thereby preserving the natural slight sweet taste of water, and reduces the wastage of water as brine (rejected water) during purification process.
[0013] Publication No. 2762/CHE/2009 discloses a reverse osmosis water purifier having a simple filter configuration, which includes filter parts consisted

of a sediment-filter, a chlorine-resistant polyamide composite membrane and a post-carbon-filter. The reverse osmosis water purifier can be designed in slim size by omitting a pre-carbon-filter, and provide drinking water of good quality since a portion of the residual chlorine in the feed water pass through the chlorine-resistant polyamide composite membrane to the downstream of said membrane and the residual chlorine can inhibit an adventitious growth of microorganism in the post-carbon-filter or the purified-water tank.
[0014] Publication No. 7217/DELNP/2008 discloses a device for purifying drinking water that has at least one fibrous structure. Preferably, there is an upstream and downstream fibrous structure. Each fibrous structure is a mixture of nano alumina fibers and second fibers arranged in a matrix to create asymmetric pores and to which fine, ultrafine, or nano size particles are attached. Preferably, the device has an upstream antimicrobial for sterilization of retained microbes. The device is substantially more efficient at removing soluble contaminants such as halogens from a fluid stream than those previously available and is also able to retain turbidity, bacteria, and virus.
[0015] Publication No. US2002158018 discloses process for producing improved alkaline water includes filtering potable source water to remove selected particles and then purifying the filtered water. Selected alkaline minerals are added to the purified water, with the resulting mineralized water being then electrolyzed to produce streams of acidic water and alkaline water, the alkaline water having a pH within the range of 9-10, a TDS range of 22-240 ppm (parts per million) and alkalinity in the range of 12-216 ppm.
[0016] Publication No. US4305826 discloses a multilayered filter for softening and filtering water. The water to be softened and filtered flows through a first layer of particles of activated carbon, a second layer of beads of an organic ion cation exchange resin, a third layer of granules of sodium aluminum silicate, and a fourth layer of grains of filter sand which layers are arranged vertically in a tank. The filter comprises the four above identified layers of filter materials.

[0017] Publication No. US2014263054 discloses a water purification system. The
water purification may include a carbon block. The water purification system may
include an ion-exchange resin layer to reduce a pH level in water before neutral
water passes into a fiber membrane filter. The water purification system may
5 include the fiber membrane filter to receive the water from the carbon block and
into a plurality of pores to remove suspended solids from the water.
[0018] Publication No. US2013180913 discloses a filter for filtering water
comprising carbon nanospheres from the pyrolytic combustion of a carbonaceous
material such as plant material which are activated with silver nitrate, activated
10 alumina and/or ferrous oxide.
[0019] Publication No. CN107226514 discloses the technical field of reverse
osmosis water treatment, in particular to a direct-current water purifier which
comprises a water inlet, a water outlet, a concentrated water draining opening, a
leakage preventing device, a pretreating device, a booster pump, a reverse osmosis
15 filtering device, a first one-way check valve, a pulse washing electromagnetic
valve and a one-way throttle valve.
[0020] Publication No. CN206494783 discloses a multifunctional water purifier,
including water purifier shell and water purifier body, the water purifier body
includes inlet three -way pipe and leading filtering component, leading filtering
20 component's exit end is connected with mineral water branch road and reverse
osmosis filter main road simultaneously, and the mineral water branch road is connected with the mineral water delivery port, and the end -to -end connection of reverse osmosis filter main road has the pure water delivery port.
[0021] Publication No. CN104860408 discloses a multiple filtration type
25 household water purifier. The multiple filtration type household water purifier
comprises a body, a first fixing frame, a second fixing frame, a water purification
bucket body, a water purification bucket cover, a transformer, a booster pump, a
water storage pressure bucket, a water inlet pipe and a water outlet pipe; the first
fixing frame and the second fixing frame are arranged inside the body; the first
30 fixing frame is located above the second fixing frame; the water purification
6

bucket body is arranged on the first fixing frame and the second fixing frame; the
water purification bucket cover is arranged on the water purification bucket body;
a filter element is arranged in the water purification bucket body; a PP (Propene
Polymer) cotton layer, an activated carbon layer, an RO (Reverse Osmosis) layer,
5 a plant activated carbon layer and a nano filtration layer are arranged in the filter
element from top to bottom in turn.
[0022] Publication No. CN205856154 discloses a reverse osmosis directly drinks water purifier, including filter equipment no. 1, filter equipment no. 2 and filter equipment no. 3, filter equipment one, filter equipment no. 2 and filter equipment
10 no. 3 all feed through integrated water route board, integrated water route inboard
is provided with a plurality of rivers passageways, the running water interface has set gradually on the board of integrated water route, life water connection mouth, the waste water interface, pressure pot interface and pure water interface, the running water interface communicates filter equipment no. 1 and filter equipment
15 no. 2 in proper order, filter equipment no. 2 communicates life water connection
mouth and booster pump respectively, booster pump intercommunication filter equipment no. 3, three intercommunication waste water interfaces of filter equipment, three intercommunication pressure pot interfaces of filter equipment, the pressure pot interface passes through pipeline intercommunication pressure
20 pot, and pressure pot interface intercommunication has U type water conservancy
diversion vertical compression formula rear -mounted filter element, U type water conservancy diversion vertical compression formula rear -mounted filter element intercommunication pure water interface.
[0023] Publication No. CN105923866 discloses a filter device of a water purifier.
25 The filter device comprises a first-level filter device, a second-level filter device, a
third-level filter device, a fourth-level filter device, a fifth-level filter device, a sixth-level filter device, a seventh-level filter device, a switch power supply, a water pump, a high-voltage switch, a low-voltage switch, a waste water proportioner, a water-intake electromagnetic valve and a reverse osmosis
30 membrane shell, wherein the first-level filter device, the second-level filter device,
7

the third-level filter device, the fourth-level filter device, the fifth-level filter
device, the sixth-level filter device and the seventh-level filter device are
sequentially serially connected, the high-voltage switch and the low-voltage
switch are respectively serially connected to two ends of the water-intake
5 electromagnetic valve, the first-level filter device is a PP cotton filter element with
the pore diameter being 5 micrometers, the second-level filter device is a 85C
granular activated carbon filter element, the third-level filter device is a PP cotton
filter element with the pore diameter being 1 micrometer, the fourth-level filter
device is a reverse osmosis (RO) membrane, the fifth-level filter device is a rear-
10 mounted activated carbon sterilizing filter element, the sixth-level filter device is a
mixed bed resin filter element, and the seventh-level filter device is an ultraviolet
sterilizer.
[0024] Publication No. CN105645520 discloses a novel domestic water purifier. The novel domestic water purifier comprises a water purifier body, a drinking
15 water tank, a reverse osmosis membrane filter layer, a water inlet and a partition
board, wherein the bottom of the water purifier body is fixedly connected with the drinking water tank, a taste regulation filter layer is arranged on the top of the drinking water tank and connected with the reverse osmosis membrane filter layer through a water channel, the reverse osmosis membrane filter layer is with an
20 activated carbon filter layer through a water channel, and the activated carbon
filter layer is connected with the partition board through a bilateral switch.
[0025] Publication No. CN205258156 discloses a portable reverse osmosis membrane water purifier, including main part, upper cover, connecting pipe, filter core, pressure device, pressure rod, water inlet and delivery port. The device
25 reasonable in design adopts reverse osmosis membrane, can get rid of the impurity
of aquatic effectively, and filterable quality of water is good, low, pollution -free, the simple process, easy and simple to handle of power consumption, exclusive manual portable pressure device has solved reverse osmosis membrane's pressurization problem, water inlet department is equipped with the safety filter
30 ware, reduces aquatic impurity to RO membrane filter core's damage, extension
8

RO membrane filter core's life, water inlet department has used check valve, and
to prevent accidental is intake and is caused the pollution to RO membrane filter
core, the device is equipped with the knapsack of cooperation braces use and
buckles, and it is more convenient to carry, be equipped with the active carbon
5 filter core, increased the taste of water, prevent to deposit the in -process accident
and intake and cause the pollution to RO membrane filter core, the filterable water of the device can reach the standard of drinking water.
[0026] Publication No. CN205115098 discloses a water purifier, including the built -in first mould shell that has the milipore filter core, be equipped with oral
10 siphon, blow off pipe and outlet pipe on the first mould shell, the outlet pipe still
is connected with reverse osmosis membrane filter equipment, and reverse osmosis membrane filter equipment includes: second mould shell and reverse osmosis membrane filter core, the seal of reverse osmosis membrane filter core warp density is fixed to be set up in second mould shell, and second mould shell
15 constitutes confined high pressure water storage chamber and waste water cavity
structure through the reverse osmosis membrane filter core, delivery port and high -pressure water storage chamber intercommunication.
[0027] Publication No. CN101357795 discloses a reverse osmosis sterilization
water purifier, comprising a reverse osmosis filter, a pressure water storage barrel
20 and a water outlet faucet which are connected with a purified water outlet of the
reverse osmosis filter by a three-way valve, and the reverse osmosis sterilization water purifier is characterized in that: a sterilization post-activated carbon filter is connected between the pressure water storage barrel and the three-way valve.
[0028] Publication No. US2010116731 discloses a reverse osmosis water purifier
25 having a simple filter configuration, which includes filter parts consisted of a
sediment-filter, a chlorine-resistant polyamide composite membrane and a post-
carbon-filter. The reverse osmosis water purifier can be designed in slim size by
omitting a pre-carbon-filter, and provide drinking water of good quality since a
portion of the residual chlorine in the feed water pass through the chlorine-
30 resistant polyamide composite membrane to the downstream of said membrane
9

and the residual chlorine can inhibit an adventitious growth of microorganism in the post-carbon-filter or the purified-water tank.
[0029] Publication No. US2014262989 discloses water filtering system including
an inlet, an outlet and a filter positioned between the inlet and the outlet, where
5 feed water enters the inlet and passes through the filter, and filtered water exits the
through the outlet. A measurement device is connected to at least one of the inlet
and the outlet measures a concentration of Total Dissolved Solids in at least one
of the inlet and the outlet. A bypass valve is connected between the inlet and the
outlet, and moves between a closed position and an open position, where the
10 filtered water moves from the outlet to the inlet. A controller communicates with
the measurement device and the bypass valve and automatically moves the bypass valve to a position between the closed position and the open position based on the concentration of the Total Dissolved Solids in the filtered water measured by the measurement device.
15 [0030] Patent No. US8951419 discloses the treatment of water and, more
particularly, to the mineralization of water in order to improve pH, hardness, turbidity, and/or alkalinity is described. More particularly, a system is provided for the treatment of water that needs additional hardness, alkalinity, and/or pH adjustment while also meeting turbidity requirements. The use of sodium
20 hydroxide and other methods for avoiding turbidity problems can be eliminated
and/or minimized.
[0031] Publication No. US2009173616 discloses a water ionizing system which
combines a traditional water ionizing machine with a reverse osmosis machine
and mineral filter. The invention can be configured several different ways, with
25 the goal of purifying the water through the reverse osmosis component, optionally
sanitizing it with UV light, then remineralizing the water with the mineral filter, and finally ionizing and alkalizing the water with the water alkaline ionizing machine.
[0032] Publication No. CN106745898 discloses a reverse osmosis water making
30 system capable of keeping water quality and a method thereof. A water inflow
10

pipeline is connected to the water inflow end of an RO membrane assembly, a
booster pump is arranged on the water inflow pipeline, a concentrated water
outflow pipeline is connected to the concentrated water outflow end of the RO
membrane assembly, and a pure water outflow pipeline is connected to the pure
5 water outflow end of the RO membrane assembly. One end of a concentrated
water backflow pipeline is communicated with the concentrated water outflow end of the RO membrane assembly, the other end of the concentrated water backflow pipeline is connected with a water inlet of the booster pump, and a combination valve is arranged on the concentrated water backflow pipeline.
10 [0033] Publication No. US7507334 discloses a water treatment system is a
modular-filter based residential reverse osmosis (RO) system that remineralizes the purified water twice to ensure the water is alkaline, but uses only one remineralization filter. The system forces the water to undergo remineralization twice in a modular-filter based residential RO system, using only one
15 remineralization filter. The water produced from the water treatment system is
alkaline with a pH of at least 7.5 up to a maximum pH of 8.5. A pH of 8.0 is the mean average.
[0034] Publication No. CN205473012 discloses a waste water zero release water purification pure water all -in -one, including filter equipment, valve, booster
20 pump, pressure pot, reverse osmosis membrane device, hyperfiltration membrane
device and active carbon device, filter equipment includes one -level filter equipment, second grade filter equipment and tertiary filter equipment, and the valve includes first check valve, water inlet solenoid valve, flush meter and second check valve, and the active carbon device includes first active carbon
25 device and second active carbon device.
[0035] Publication No. CN205346990 discloses a two play water installations of
RO reverse osmosis, including the pressure pot, the pressure pot passes through
the pipeline and links to each other with pyatyi filter equipment and fourth stage
filter equipment respectively, fourth stage filter equipment's inner chamber is
30 equipped with RO membrane device, the top of pure water pipeline and mineral
11

substance water pipeling is equipped with total valve, the top of total valve is
equipped with outlet conduit, the right -hand member of mineral substance water
pipeling is equipped with third level filter equipment, and third level filter
equipment's inner chamber is equipped with hyperfiltration membrane device,
5 third level filter equipment's right side is equipped with second level filter
equipment, and second level filter equipment's right side is equipped with first order filter equipment.
[0036] Publication No. CN207210031 discloses a reverse osmosis water processing technique field especially relates to a direct current water purification
10 machine, including water inlet, delivery port, concentrated water drainage
opening, leak protection device, preprocessing device, booster pump, reverse osmosis filter device, first one -way check valve, pulse flushing solenoid valve, one -way throttle valve, cancelled rear mounted activated carbon in the pure water route, the secondary pollution who has avoided "carbon dust", "arsenic" and
15 "bacterium" probably ensures water quality safety and drinking water taste, above
-mentioned reverse osmosis filter device pure water delivery port loops through the second tube coupling and arranges salt valve, the one -way check valve of third, concentrated water drainage opening simultaneously, realizes the start and arranges salt, and establish choke valve and miniature pressure water storage tank
20 in the pure water route, the bad difficult problem of initial taste that the TDS value
of comprehensively having solved reverse osmosis membrane pure water after the shutdown rose and brings.
[0037] Publication No. CN107399837 discloses an integrated reverse osmosis filter element. A water collecting pipe is arranged at the center of the reverse
25 osmosis filter element, a water collecting hole is formed in the water collecting
pipe, and purified water filtered by the reverse osmosis filter element is collected by the water collecting hole and flows into the water collecting pipe; and a rear filter element is arranged in the water collecting pipe, and the rear filter element further filters the purified water flowing into the water collecting pipe. By virtue
30 of the arrangement, the rear filter element is arranged in the water collecting pipe
12

of the reverse osmosis filter element in an integrated way, so that the reverse
osmosis filter element integrates the rear filter element which has the functions of
improving taste of the purified water filtered by a reverse osmosis membrane and
adding minerals; meanwhile, overall size of the integrated reverse osmosis filter
5 element after integration is not changed, and the aims of optimizing design,
reducing the number of the filter elements and improving filter element integration level are achieved; and besides, the integrated reverse osmosis filter element provided by the invention is simple in structure, obvious in effect and applicable to popularization and application.
10 [0038] Patent No. US8252171 discloses water purifying and enhancement system
of a modular construction designed as a built-in appliance located under the
countertop or as a free-standing (standalone) unit. The water appliance has a water
inlet for obtaining water from a supply source, scale reduction device, booster or
re-pressurization pump, pre-filtration, U.V. sterilization, R.O. filtration, de-
15 ionization (CDI or mechanical), mineral injection system (for adding desired
minerals into the purified water), water diagnostic and monitoring cells, post
filtration, proprietary water enhancement reactor consisting of specially
engineered and blended ores of ceramic components, and/or an electrolytic
ionization chamber, and/or a magnetic chamber, a water outlet for delivery of the
20 highly purified enhanced water product, and a outlet to grey water drain for reject
water.
[0039] The article entitled “7 easy ways to enliven your drinking water with
minerals for better health” by Karen Peltier, Well Gal,2014 – 2018. talks about
the Use a pH-balancing filter for your reverse osmosis system. Does your RO
25 water taste too pure? That’s probably because about 99% of the minerals have
been stripped from it. Correct the problem by raising the pH and adding calcium and magnesium back in with a simple filter, which is often called a pH-balancing, calcite, or remineralizing filter. By the way, you may not necessarily have to change your RO system, because it’s an add-on filter. But you will need to change
13

the filter occasionally — perhaps twice yearly — and pay around $30 – $50 each time for a new one.
[0040] The article entitled “Zip countertop reverse osmosis water filter with
patented high capacity 4 stage alcapure technology - superior taste, purity, and
5 alkaline pH | no installation or assembly required” by PuricomUSA, 1996-2018
talks about the transforms ordinary tap water into clean, healthy, delicious and alkaline drinking water, BPA Free. This removes up to 99% of all contaminants: Fluoride, Chlorine, Heavy Metals & others 50% recovery rate highest among reverse osmosis filters and uses less power than a lightbulb only 24W.
10 [0041] In general, in a RO water purifier, raw water first passes through a Micron
filter, to remove suspended impurities and Activated carbon adsorbed to reduce residual chlorine and other organic impurities before entering the RO membrane. Reverse osmosis membrane removes dissolved chemicals including hazardous heavy metals ions, pesticides and microbiological impurities like bacteria, viruses
15 and cysts from the polluted water. The permeate of RO water is further subjected
to activated carbon treatment to remove volatile organic compounds and gases which may deteriorate the taste & impart objectionable odor to purified water. Addition of an Ultra violet (UV) radiation disinfection as a secondary treatment gives an added advantage.
20 [0042] In the event of permeate water turning acidic many RO water purifier
manufactures started mixing filtered raw water to RO membrane treated water to reduce the bitterness caused by reduction in pH and thereby handling consumer objections.
[0043] In one of the existing method (Figure 1) the raw water first passes through
25 a Micron Filter (01) and an activated carbon adsorber (04). After Activated
Carbon filter the stream is divided into two. Whereas one stream passes through RO membrane (06) the second bypasses the RO membrane. To enhance the clarity of RO membrane bypasses stream an Ultra Filter (09) is employed. Both the streams confluences and passes through UV disinfection column (07) and an
14

Activated carbon adsorber (11). The resultant purified water is collected in a reservoir (08).
[0044] A solenoid valve (02) to control the flow of water and a combination of
pressure booster pump (03) & Flow restrictor (05) are used to generate required
5 pressure for RO membrane working, in raw water stream after Micron Filter.
[0045] The heart of this method is a valve (10) which controls the flow of RO
bypassed stream thereby deciding the mixing ratio of flow of two streams i.e. RO
treated and RO bypassed stream. This method of correcting the pH is often termed
as taste enhancing or TDS blending and the valve is termed as TDS/ Taste
10 controller/ Blender (10).
[0046] In this method both water purification and safety of consumer are
compromised. The main benefit of employing RO treatment method is its
capability of removing hazardous chemicals like heavy metals, pesticide from
water which are allowed to bypass while satisfying the taste and balancing the pH
15 of water unknowingly.
[0047] In another existing method (Figure 2) 100% water after activated carbon adsorber passes through RO membrane followed by a mineral cartridge (12). The mineral cartridge (12) contains natural/ artificial granules of mineral salts like calcite & magnesium which releases selected minerals to RO permeate water. A
20 drop in pH, post RO membrane, if any, is increased back by the addition of
minerals like calcium and/or other alkaline minerals. As the drop in pH post RO membrane varies depending on the chemistry of feed water the pH post mineral cartridge will also vary. The only benefit of this method is that it brings back the pH of purified water to alkaline range and addresses the issue of objectionable
25 taste to consumer.
[0048] In order to overcome the limitations of above listed prior art, the present invention aims to provide a system and method of adjusting the pH of reverse osmosis membrane permeate water in a point of use (POU) water treatment system. The permeate of RO membrane is blended with the RO permeate passed
15

through alkaline mineral cartridge in desired proportion to bring the pH to desired level.
[0049] The information disclosed in this background of the disclosure section is
only for enhancement of understanding of the general background of the invention
5 and should not be taken as an acknowledgement or any form of suggestion that
this information forms the prior art already known to a person skilled in the art.
OBJECTS OF THE INVENTION:
[0050] It is therefore the object of the invention to overcome the aforementioned and other drawbacks in prior washers.
10 [0051] The principal objective of the present invention is to provide a system and
method of adjusting the pH of reverse osmosis membrane permeate water to desired level within in a point of use (POU) water treatment system.
[0052] Another object of the present invention is to provide a better and acceptable taste of RO purified water with varying feed water chemistry.
15 [0053] Yet another object of the present invention is to provide a system and
methods of controlling the pH of reverse osmosis membrane permeate water by using pH blender & alkaline mineral cartridge.
[0054] Yet another objective of the present invention is to provide a failsafe
mechanism by which two streams, RO permeate water and RO permeate water
20 with high pH can be adjusted in inversely proportional volumes keeping the
volume of water before bifurcation of the streams and after the confluence of streams unchanged.
[0055] These and other objects and advantages of the present subject matter will
be apparent to a person skilled in the art after consideration of the following
25 detailed description taken into consideration with accompanying drawings in
which preferred embodiments of the present subject matter are illustrated.
SUMMARY OF THE INVENTION:
16

[0056] In accordance with the said objectives, the present invention provides a
system and method of adjusting the pH of reverse osmosis membrane permeate
water in a point of use (POU) water treatment system. The permeate of RO
membrane is blended with the RO permeate water with added alkaline minerals in
5 controlled manner to balance and control the pH of purified water. The present
invention provides a better and acceptable taste of RO purified water. The pH of purified water is adjusted by using pH blender & alkaline mineral cartridge.
[0057] The foregoing summary is illustrative only and is not intended to be in any
way limiting. In addition to the illustrative aspects, embodiments, and features
10 described above, further aspects, embodiments, and features will become apparent
by reference to the drawings and the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0058] It is to be noted, however, that the appended drawings illustrate only typical embodiments of the present subject matter and are therefore not to be
15 considered for limiting of its scope, for the invention may admit to other equally
effective embodiments. The detailed description is described with reference to the accompanying figures. In the figures, a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the figures to reference like features and components. Some embodiments of
20 system or methods or structure in accordance with embodiments of the present
subject matter are now described, by way of example, and with reference to the accompanying figures, in which:
[0059] Figure 1 shows the existing method where the raw water first passes through a micron filter and an activated carbon adsorber.
25 [0060] Figure 2 shows another existing method where 100% water after Activated
carbon adsorber passes through RO membrane followed by a mineral cartridge.
[0061] Figure 3 shows the block diagram according to the present invention.
[0062] Figure 4 shows construction of pH blender according to the present invention.
17

[0063] The figures depict embodiments of the present subject matter for the
purposes of illustration only. A person skilled in the art will easily recognize from
the following description that alternative embodiments of the structures and
methods illustrated herein may be employed without departing from the principles
5 of the disclosure described herein.
DESCRIPTION OF THE PREFERRED EMBODIMENTS:
[0064] While the embodiments of the disclosure are subject to various
modifications and alternative forms, specific embodiment thereof have been
shown by way of example in the figures and will be described below. It should be
10 understood, however, that it is not intended to limit the disclosure to the particular
forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternative falling within the scope of the disclosure.
[0065] The terms “comprises”, “comprising”, or any other variations thereof used in the disclosure, are intended to cover a non-exclusive inclusion, such that a
15 device, system, assembly that comprises a list of components does not include
only those components but may include other components not expressly listed or inherent to such system, or assembly, or device. In other words, one or more elements in a system or device proceeded by “comprises… a” does not, without more constraints, preclude the existence of other elements or additional elements
20 in the system or device.
[0066] It should be noted that the description and figures merely illustrate the principles of the present subject matter. It should be appreciated by those skilled in the art that conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the
25 same purposes of the present subject matter. It should also be appreciated by those
skilled in the art that by devising various arrangements that, although not explicitly described or shown herein, embody the principles of the present subject matter. Furthermore, all examples recited herein are principally intended expressly to be for pedagogical purposes to aid the reader in understanding the principles of
30 the present subject matter and the concepts contributed by the inventor(s) to
18

furthering the art, and are to be construed as being without limitation to such
specifically recited examples and conditions. The novel features which are
believed to be characteristic of the present subject matter, both as to its
organization and method of operation, together with further objects and
5 advantages will be better understood from the following description when
considered in connection with the accompanying figures.
[0067] These and other advantages of the present subject matter would be
described in greater detail with reference to the following figures. It should be
noted that the description merely illustrates the principles of the present subject
10 matter. It will thus be appreciated that those skilled in the art will be able to devise
various arrangements that, although not explicitly described herein, embody the principles of the present subject matter and are included within its scope.
[0068] Accordingly the present invention provides a system and method of
adjusting the pH of reverse osmosis membrane permeate water in a point of use
15 (POU) water treatment system. The invention provides the method of adjusting
the pH of reverse osmosis membrane permeate water in a POU water treatment system.
[0069] In the present invention (Figure 3) the raw water first passes through a
Micron Filter (01) and an activated carbon filter (04). After Activated Carbon
20 filter 100% water is allowed to pass through RO membrane (06). A solenoid valve
(02) to control the flow of water and a combination of pressure booster pump (03) & Flow restrictor (05) are used to generate required pressure for RO membrane working, in raw water stream after Micron Filter.
[0070] The RO permeate water stream is divided into two stream. One stream
25 (Stream B) passes through an alkaline mineral cartridge (12) which can increase
the pH of water up to 9.5. Another stream carries the RO permeate water (Stream A). Both the streams, Stream A and B enters in to a specially designed blender valve (13). The blender valve is designed to control the flow of the two incoming streams in inversely proportional volumes.
19

[0071] Figure 4 illustrates the construction of blender valve (13). Inlet holes A2
(15) & B2 (16) for Stream A & Stream B are aligned at 180° from each other with
aperture diameter of 6.0 mm on the main body (13) of the blender valve. The
dome shaped plunger (14) fixed inside the main body has same diameter holes A1
5 (17) & B1 (18) but at 135° to each other with aperture diameter of 6.0 mm and
coinciding with valve body inlet holes A2 (15) & B2 (16). The inner diameter
(19) of dome shaped plunger gives way to the outlet liquid through the main body
of the valve outlet (20). The plunger is so adjusted in the valve body that hole A2
(15) of main body aligns with the one of the plunger hole A1 (17) in totality. In
10 this situation the hole B2 (16) of the valve body will be 100 % misaligned with
another hole B1 (18) of plunger. In such situation, 100% water of stream A and 0% from stream B will flow out to the outlet (20) of the valve.
[0072] If the plunger is rotated clockwise and to the extent where hole B2 (16) of
the main body coincides with the hole B1 of the plunger. In this situation 0%
15 water form stream A and 100% from stream B will flow to the outlet of valve
(20). This situation is just opposite of earlier situation.
[0073] Now if the plunger is rotated in anticlockwise direction slowly the proportion of Stream B will start reducing and the proportion of stream A will start increasing in the magnitude equal to the proportion stream B is reducing.
20 This way one can increase or decrease the flow from stream A & B in inversely
proportional volume to each other. While adjusting both the streams at a certain angle, the total sum of opening area will remain the same, therefore, the flow rate will be same in all the above situations. This will avoid the chance of restricting the flow of RO membrane permeate or generating any back pressure on RO
25 membrane. This will also maintain the ratio/ percent flow of both stream over the
life of membrane, where total permeate flow is varying over the life of RO membrane.
[0074] The method will facilitate and control the mixing of desired ratio of
volume of Stream A & Stream B in different but inversely proportional volume.
30 This will result in varying the resultant pH of outlet water from the valve and will
20

allow to set the pH between the pH of Stream A (minimum) & pH of Stream B (maximum).
[0075] Purified water with desired pH range/ value is further subjected to UV
disinfection (07). A post carbon filter (11) can also be added if desired to remove
5 VOC from purified water.
[0076] It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be
10 interpreted as “having at least,” the term “includes” should be interpreted as
“includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the
15 following appended claims may contain usage of the introductory phrases “at least
one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even
20 when the same claim includes the introductory phrases “one or more” or “at least
one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited,
25 those skilled in the art will recognize that such recitation should typically be
interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a
30 construction is intended in the sense one having skill in the art would understand
21

the convention (e.g., “a system having at least one of A, B, and C” would include
but not be limited to systems that have A alone, B alone, C alone, A and B
together, A and C together, B and C together, and/or A, B, and C together, etc.).
In those instances where a convention analogous to “at least one of A, B, or C,
5 etc.” is used, in general such a construction is intended in the sense one having
skill in the art would understand the convention (e.g., “a system having at least
one of A, B, or C” would include but not be limited to systems that have A alone,
B alone, C alone, A and B together, A and C together, B and C together, and/or A,
B, and C together, etc.). It will be further understood by those within the art that
10 virtually any disjunctive word and/or phrase presenting two or more alternative
terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.”
15 [0077] It will be further appreciated that functions or structures of a plurality of
components or steps may be combined into a single component or step, or the functions or structures of one-step or component may be split among plural steps or components. The present invention contemplates all of these combinations. Unless stated otherwise, dimensions and geometries of the various structures
20 depicted herein are not intended to be restrictive of the invention, and other
dimensions or geometries are possible. In addition, while a feature of the present invention may have been described in the context of only one of the illustrated embodiments, such feature may be combined with one or more other features of other embodiments, for any given application. It will also be appreciated from the
25 above that the fabrication of the unique structures herein and the operation thereof
also constitute methods in accordance with the present invention. The present invention also encompasses intermediate and end products resulting from the practice of the methods herein. The use of “comprising” or “including” also contemplates embodiments that “consist essentially of” or “consist of” the recited
30 feature.
22

[0078] Although embodiments for the present subject matter have been described in language specific to structural features, it is to be understood that the present subject matter is not necessarily limited to the specific features described. Rather, the specific features and methods are disclosed as embodiments for the present subject matter. Numerous modifications and adaptations of the system/component of the present invention will be apparent to those skilled in the art, and thus it is intended by the appended claims to cover all such modifications and adaptations which fall within the scope of the present subject matter.
[0079] Components:
[0080] 1. Micron Filter
[0081] 2. Solenoid Valve
[0082] 3. Pressure Booster Pump
[0083] 4. Activated Carbon Adsorber
[0084] 5. Flow Restrictor
[0085] 6. RO Membrane
[0086] 7. WDisinfection Column
[0087] 8. Purified Water Storage Tank
[0088] 9. Ultra Filtration Cartridge
[0089] 10. TOS Blender I Taste Enhancer
[0090] 11. Post Activated Carbon Filter
[0091] 12. Mineral/pH Enhancer Cartridge
[0092] 13. Valve for Inversely proportional water mixing from two streams

We claim:

A system for adjusting the pH of reverse osmosis membrane permeate
water, the system comprises:
A micron filter (01) and an activated carbon filer (04) for first pass of raw
water;
An RO membrane (06) for passing of 100% activated carbon filer water;
A solenoid valve (02) to control flow of water;
A pressure booster pump (03);
A flow restrictor (05) to generate required pressure for RO membrane; and
An Alkaline taste enhancer cartridge (12);
A pH blender (13);
Characterized in that
The pH blender (13) comprises of two inputs and one output wherein two
streams of purified water are blended together to provide a balance pH
water.
The system as claimed in claim 1, wherein the pH blender (13) consists of
Inlet holes A2 (15) & B2 (16) for Stream A & Stream B aligned at 180°
from each other with aperture diameter on the main body (13) of the
blender valve, the dome shaped plunger (14) fixed inside the main body
has same diameter holes Al (17) & Bl (18) but at 135° to each other with
aperture diameter and coinciding with valve body inlet holes A2 (15) &
B2 (16), the inner diameter (19) of dome shaped plunger gives way to the
outlet liquid through the main body of the valve outlet (20).
A method for adjusting the pH of reverse osmosis membrane permeate
water, the method comprising steps of:
Passing the raw water through the Micron Filter (01) and the activated
carbon filter (04);
The Activated Carbon filter 100% water is passed the RO membrane (06);
The solenoid valve (02) controls the flow of water;

a combination of pressure booster pump (03) & Flow restrictor (05)
generate required pressure for working of RO membrane (06), in raw
water stream after Micron Filter;
dividing the RO permeate water stream is divided into two streams (A &
B);
characterized in that
Stream B passes through an alkaline mineral cartridge (12) to increase the
pH of water;
Stream A carries the RO permeate water;
Stream A and B enters the pH blender (13) wherein they are mixed by
adjusting the plunger (14) to produce purified water with adjusted pH.
The method as claimed in claim 3, wherein the plunger is adjusted in the
valve body that hole A2 (15) of main body aligns with the one of the
plunger hole Al (17) in totality, the hole B2 (16) of the valve body will be
100 % misaligned with another hole Bl (18) of plunger and, 100% water
of stream A and 0% from stream B will flow out to the outlet (20) of the
valve.
The method as claimed in claim 3, wherein if the plunger (14) is rotated clockwise and to the extent where hole B2 (16) of the main body coincides with the hole Bl of the plunger and 0% water form stream A and 100%) from stream B will flow to the outlet of valve (20).
The method as claimed in claim 3, wherein if the plunger is rotated in anticlockwise direction slowly the proportion of Stream B will start reducing and the proportion of stream A will start increasing in the magnitude equal to the proportion stream B is reducing. The method as claimed in claim 3, wherein the pH blender blends two streams of purified water with the blending device having two inputs and one output, in a specific proportions to maintain the pH of purified water without affecting the total volume.

The method as claimed in claim 3, wherein the two streams (stream A & B) includes the purified alkaline mineral water with pH ranging between 9.0 and 9.5 and the RO permeate water with pH ranging 5.0 to 8.0.