DESC:Field of the Invention:

The present Invention is in the field of water filtration/purification. The Invention provides a filtration method, filter media and a filtration system for the treatment of water. Particularly, a filtration method, filter media and a filtration system for elimination/removal of heavy metals like Iron, manganese from water.

Background of the Invention:

The following background discussion includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.

The environmental issues due to globalization and rapid industrialization are becoming more and more nuisance for human being. Heavy metal pollution has become one of the most serious environmental problems nowadays. Heavy metal contamination of drinking water supplies has become of particular concern in recent years due to the accelerated pace of industrialization.

Metals like Iron, manganese etc. are most common metals found in the water of subterranean and surface sources. These heavy metals find their way into drinking water and pollute the same. Iron, even in small quantities, can be one of the most troublesome elements found in water. Exceeding the suggested maximum contaminant level (0.3mg/L) usually results in discolored water, laundry, and plumbing fixtures. The taste of beverages, such as tea and coffee, may also be affected by iron. Iron is a big threat for reverse osmosis membrane and more than 0.3mg/L of iron concentrate in feed water will affect the membrane performance significantly. Similarly, arsenic and manganese too have detrimental effect and decreases the quality of potable water.

Even though the clear water meets the drinking water standards, still the water quality can deteriorate due to heavy metals and particularly due to settling of iron (hydroxide) particles. Therefore, it is important to remove dissolved and particulate heavy metals like iron, manganese to a large extent. Water filtration systems for removing heavy metals and other contaminants from water have long been in use.
Filtration system are usually made by incorporating pH balancing as first stage followed by oxidation media as second stage and Sediment filter as the final stage. However, under such assembly, if sufficient amount of oxygen is available in the feed water supplied to the filtration, there is rise in the pH in first stage and thus the precipitation of ferric oxide happens in first stage itself. These precipitate gets deposited on the oxidation media in the second stage thereby reducing the filter efficiency. Because of this, higher volume of oxidation media and frequent flushing/regeneration is required. Periodic backwashing is also necessary to remove the precipitated iron from the bed.

As with water softeners, filters, particularly iron filters do have limitations. Since the oxidizing action is relatively mild, it will not work well when organic matter, either combined with the iron or completely separate, is present in the water. Extremely high iron concentrations may require inconvenient frequent backwashing and/or regeneration. Finally, iron filter media requires high flow rates for proper backwashing and such water flows are not always available.

The traditional filtration methods also includes ion exchange for iron removal, but this method works best when the iron concentration is low and when all or most of the iron is in the soluble state.
In those cases where neither ion exchange nor iron filters are applicable, chemical feed pumps and filters may be used in combination with great effectiveness. In such cases, a chemical feed pump may be used to introduce a solution of an oxidizing agent such as sodium or calcium hypochlorite or potassium permanganate, into the feed water. The oxidizing agent will then not only oxidize soluble iron to the insoluble ferric state, but will also attach any organic matter present. In that case, when either of the hypochlorite/s are used, the water will be disinfected at the same time. These oxidizing solutions should be fed into the water line ahead of a mixing and contact tank to ensure complete reaction with the iron and organic matter and to allow coagulation of small particles into filterable sizes. In most cases, the pressure tank of a private water system fills this need, but occasionally, slowly acting forms of organic matter require additional contact time. In such cases, additional tanks or contact vessels must be provided.

It is also noted that most of the Filter system for removing heavy metals as described above are designed as Point of Entry system which tends to be bulky, based on electricity for pumping in oxygen for oxidation step or need pro-long regeneration step. Hence, there is needed is a “point of use” filter system for removing heavy metals like Iron, manganese.

The filter media plays an important role in the filtration method and thus the efficiency of filtration also depends on the media being used. Below mentioned are different types of media/s being used commercially. However, these media/s suffers with one or the other drawback/s i.e. either they need much larger volume of media to achieve similar reduction, require complicated flushing and regeneration process, or both, which is not feasible in a domestic application.

a) Green sand: This suffer with the drawback that the capacity of media required is very high (~ 25 Kgs to treat 6000 Litres which is typically the volume of water needed per year for drinking for a family of 4) from 3 ppm to 0.3 ppm, whereas standard 10” POU housing can accommodate only ~650gms of the media.

b) Ion Exchange Resin: Here, the capacity of media required would be ~ 5 Kgs to treat 6000 Liters from 3 ppm to 0.3 ppm. Storage of the media is an issue as it is sensitive to heat and moisture. If not stored properly, the media performance would not be optimal.

c) Birm: The capacity of media required would be ~ 2 Kgs to treat 6000 Liters from 3 ppm to 0.3 with regeneration. Good oxidation of Iron but found higher pressure drop and frequent back flush required.

Manganese dioxide and its ore are long known to remove iron, manganese and many other compounds. It creates a catalytic effect in the chemical oxidation-reduction reactions necessary to remove iron, manganese, H2S and radium. Manganese dioxide’s catalytic reaction allows iron and manganese that are not oxidized to catalytically precipitate and be adsorbed directly onto MnO2-based media. Similarly, Greensand is a popular media on the market that uses a host material and coats it with manganese dioxide. These products are designed to be lighter and require a lower backwash rate. Greensand is an industry standard going back decades. It is a mined zeolite that receives a MnO2 coating. But Greensand requires regeneration with potassium permanganate (KMnO4) to retain their MnO2 properties.

For bringing the Fe level below the drinkable range in the final water, MnO2 ore bed is required as using just Greensand is not sufficient. However, using just MnO2 is not advised due to increase of turbidity of the product water, specifically during stagnation of the system (unit not running for 24 hr or more). Hence, there is needed a filter media, particularly an oxidation-adsorption media which can be used as on-line filter with higher flow rates and at the same time capable of removing the heavy metals below the drinkable limit like removing Iron to below the drinkable limit that is 0.3mg/L.
There is needed an efficient oxidation-adsorption media and filtration method using the same, for the removal of heavy metals like Iron, manganese etc. Particularly, an oxidation-adsorption media which can achieve reduction of Iron and manganese in final product water.

Also, in view of the above described prior art, there is a need of a highly efficient filtering system, carrying out the filtering method for removal of heavy metals (like Iron, manganese etc.), which can be used as Point of Use, does not depend on electricity for its operations, is simple and economical, easy to use and of reasonable size so that it can be fitted in a household as Point of Use system.

Object(s) of the Invention:

A primary object of the present invention is to overcome the drawback/s associated with the prior art.

Yet another object of the present invention is to provide a method of removing contaminants, particularly heavy metals comprising Iron, manganese, present in various forms including dissolved, particulate or colloidal form from water.

Yet another object of the present invention is to provide an oxidation-adsorption filter media for removal of heavy metals comprising Iron, manganese from water.

Yet another object of the present invention is to provide a filter media which can be used as on-line filter with higher flow rates and at the same time capable of removing heavy metals like Iron, manganese to below the drinkable limit.

Yet another object of the present invention is to provide a heavy metal removal system for removing heavy metals comprising Iron, manganese, that can be used as Point of Use, which does not depend on electricity for its operations, easy to use, cost effective and of reasonable size that can be fitted in a household as point of use system.

Yet another object of the present invention is to provide a heavy metal removal system for removing heavy metals comprising Iron, manganese, which is portable, easy to install, standalone and electricity free system.
Yet another object of the present invention is to provide a heavy metal removal system for removing heavy metals comprising Iron, manganese, for carrying out the filtration method.

Yet another object of the present invention is to provide a method of removing contaminants, particularly iron, manganese, present in various forms including dissolved, particulate or colloidal form from water.

Yet another object of the present invention is to provide an iron removal method, which achieves the reduction of Iron over 95% in final product.

Yet another object of the present invention is to provide an iron removal method, which can reduce the concentration from 2 ppm to permissible drinkable limit of 0.3ppm with flow rate of approximately 1 litre per minute.

Yet another object of the present invention is to provide a manganese removal method, which achieves the reduction of manganese over 95% in final product.

Yet another object of the present invention is to provide a manganese removal method, which can reduce the concentration from 0.5 ppm to permissible drinkable limit of 0.1ppm with flow rate of approximately 1 litre per minute.

Yet another object of the present invention is to provide a method of removing heavy metals like iron and manganese from water, by controlling the Eh – pH stability of the metals in water, so as to achieve rapid oxidation of the metals in minimum dissolved oxygen.

Yet another object of the present invention is to provide a power saving method of removing iron, manganese which runs without electricity.

Yet another object of the present invention is to provide a filter media for removal of Iron, manganese in water.

Yet another object of the present invention is to provide a filter media which can be used as on-line filter with higher flow rates and at the same time capable of removing heavy metal contamination comprising Iron and manganese, to below the drinkable limit.

Yet another object of the present invention is to provide an Iron and manganese removal system that can be used as Point of Use, which does not depend on electricity for its operations, easy to use, cost effective and of reasonable size that can be fitted in a household as point of use system.

Yet another object of the present invention is to provide an Iron and manganese removal system for carrying out the filtration method as described above.

Summary of the Invention:
In an aspect of the Invention, there is provided a water purification method by removing heavy metal contamination from a liquid sample, comprising steps:
a) treating said liquid sample at pH ranging from 7.2 to 8.5 where said treatment causes oxidation followed by hydrolysis for the precipitation of said heavy metal in the hydroxide form in the first pH boosting media;
b) passing the water resulting from step (a) through the first filter to a sediment filter for removing the precipitate of hydroxide form of said heavy metal;
c) treating the liquid sample resulting from the step (b) through an oxidation-adsorption filter media, where said media comprises filter bed of MnO2 and green sand present in a ratio ranging from 2.4:1.2 to 3:1, to obtain the purified water by the removal of said heavy metal contamination.
In another aspect of the Invention, there is provided an oxidation-adsorption filter media for removing heavy metal contamination by oxidizing and adsorbing the heavy metal present in a liquid sample comprising filter bed of MnO2 and green sand present in a ratio ranging from 2.4 :1.2 to 3:1.

In another aspect of the Invention, there is provided water purifier for removing heavy metal contamination from a liquid sample, comprising:

a) atleast a pH booster media for precipitating said heavy metal in hydroxide form, where said media maintains the pH ranging from 7.2 to 8.5;
b) atleast a sediment media for removing the precipitated heavy metal resulting from the pH booster media;
c) atleast an oxidation-adsorption filter media, where said media comprises filter bed of MnO2 and green sand present in a ratio ranging from 2.4:1.2 to 3:1, to obtain the purified water by the removal of said heavy metal contamination.

Brief Description of the Drawings

To further clarify advantages and features of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof, which is illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail with the accompanying drawings in which:

Figure 1 illustrates a schematic overview of the filtration device of the present Invention
Figure 2 illustrates results of the Iron reduction study using Three-Stage Filtration System (Calcite, Sediment filter & optimized ratio of Greensand and MnO2 media)
Figure 3 illustrates performance with Calcite and only Greensand
Figure 4 illustrates results of the Iron reduction study using Three-Stage Filtration System with only MnO2, Only Greensand, 3:1, 1:3 and 1:1 ratio of Greensand to MnO2 media
Figure 5 illustrates results of the Turbidity of product water of the above Ratios under different run conditions (continuous run and stagnation)
Figure 6 illustrates Iron reduction studies using Three-Stage Filtration System with MnO2 and Greensand where the ratios of Greensand to MnO2 are maintained as 2.8:1.2, 2.6:1.4, 2.4:1.6 and 2.2:1.8
Figure 7 illustrates results of the turbidity studies of product water treated/filtered with the ratios of Greensand to MnO2 as 2.8:1.2, 2.6:1.4, 2.4:1.6 and 2.2:1.8 media under different run conditions (continuous run and stagnation)
Figure 8 illustrates manganese reduction studies where the graph shows Manganese Reduction Vs Total Flow

Detailed Description of the Invention

For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated system, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.
It will be understood by those skilled in the art that the foregoing general description and the following detailed description are exemplary and explanatory of the invention and are not intended to be restrictive thereof. Throughout the patent specification, a convention employed is that in the appended drawings, like numerals denote like components.

Reference throughout this specification to “an embodiment”, “another embodiment”, “an implementation”, “another implementation” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrase “in an embodiment”, “in another embodiment”, “in one implementation”, “in another implementation”, and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.

The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a method that comprises a list of steps does not include only those steps but may include other steps not expressly listed or inherent to such method. Similarly, one or more devices or sub-systems or elements or structures proceeded by "comprises... a" does not, without more constraints, preclude the existence of other devices or other sub-systems or other elements or other structures or additional devices or additional sub-systems or additional elements or additional structures of the flow restrictor as described below.

For the instant description, the terms “filtration”, “purification” and “treatment” are used interchangeably.

In similar manner, the terms “purification apparatus”, “filtration apparatus”, “filtration device”, “treatment system”, “treatment device” are used interchangeably.

The Invention provides a filtration method, filter media and a filtration system for the treatment of water. Particularly, a filtration method, filter media and a filtration system for elimination/removal of heavy metals like Iron, manganese from water.

In an aspect of the Invention, there is provided an oxidation-adsorption filter media for removing heavy metal contamination like Iron and manganese by oxidizing and adsorbing the heavy metal present in a liquid sample comprising filter bed of MnO2 and green sand present in a ratio ranging from 2.4 :1.2 to 3:1.

In an embodiment, the filter media comprises MnO2 with approximately 80% purity.

In an embodiment, the filter media comprises greensand with approximately its 35% surface coated with MnO2.

The present Invention provides a method of removing contaminants, particularly heavy metals like iron, manganese from water. Particularly, the method is useful for eliminating/removing iron and manganese present in various forms including dissolved, particulate or colloidal form, in water.

The purification/ filtration method and purification/ filtration system of the present Invention has been described with respect to removal of iron and manganese from water in one of its preferred embodiment, however, the scope of Invention should not be considered as limiting to removal of Iron and manganese rather the purification/ filtration method and purification/ filtration system are equally effective for the removal of other heavy metals as well. Figure 1 shows a schematic view of the filter system of the present Invention.

In an aspect of the Invention, there is provided a water purification method by removing heavy metal contamination from a liquid sample. The method comprises following steps:

a) treating said liquid sample at pH ranging from 7.2 to 8.5 where said treatment causes oxidation followed by hydrolysis for the precipitation of said heavy metal in the hydroxide form in the first pH boosting media;
b) passing the water resulting from step (a) through the first filter to a sediment filter for removing the precipitate of hydroxide form of said heavy metal;
c) treating the liquid sample resulting from the step (b) through an oxidation-adsorption filter media, where said media comprises filter bed of MnO2 and green sand present in a ratio ranging from 2.4:1.2 to 3:1, to obtain the purified water by the removal of said heavy metal contamination.

In an embodiment, the heavy metals comprises Iron, manganese.

In an embodiment of the Invention, there is provided a method of removing Iron from water.The method comprises following steps:
a) Step 1- pH Treatment:
This step is pH-dependent where pH value ranging from 7.2 to 8.5 in the first filter is maintained. The pH causes oxidation of Fe2+ to Fe3+ followed by hydrolysis of Fe3+ to iron hydroxides and precipitation of the hydroxide particles.
In an embodiment, the pH is maintained by using Calcium Carbonate.

b) Step 2- Sediment Filter:
In the 2nd stage, the water resulting out of the 1st stage passes through the Sediment filter. This filter acts as a separator to remove the precipitates of hydroxide particles. The total heavy metal contamination like Iron removed till 2nd stage is more than 80%.

c) Step-3: Oxidation-adsorption Media:
This stage of filtration comprises customized oxidation-adsorption media, which efficiently oxidizes and adsorb the trace amount of iron present in water after the second stage of filtration and fine tune the water quality for getting maximum iron removal that is below 0.3ppm. This step is one of the important step of the method wherein if any Iron (II) that is not converted to Fe (3+) in the 1st stage, it is removed now in this step by adsorption onto the surface of the filter media. Subsequently, in the presence of oxygen, the adsorbed Iron (II) is oxidized forming a new surface for adsorption. In this way the process continues to filter Iron from water.
In an embodiment, the method reduces the concentration of iron from 2 ppm to permissible drinkable limit of 0.3ppm with flow rate of approximately 1 litre per minute. The method reduces the Iron content over 95% in the resulting purified water.

In another embodiment of the Invention, there is provided a method of removing manganese from water. The method comprises following steps:

a) As this process is pH-dependent, a controlled quantity of pH boosting media (like calcite) is used in the 1st filter to achieve water pH range between 7.2 – 8.5 for rapid oxidation of Mn2+ to Mn4+, Hydrolysis of Mn4+ to MnO2 and precipitated continuously for 12000L.

b) In the 2nd stage, the water out of the 1st stage passes through the separator filter. This filter acts as a separator to remove the precipitate of hydroxide particles.

c) The 3rd and final stage uses a specially formulated mixture of Greensand and MnO2 as adsorption-oxidation filter to achieve the final concentration of Manganese (Mn) in product water less than 0.1 ppm (Drinking water limit as per IS 10500). In the adsorption-oxidation (adsorptive filtration) mechanism, any Mn(II) that is not converted to precipitate in the 1st stage is removed by adsorption onto the surface of the filter media continuously till 12000L. The results are shown in Figure 8. The method reduces the manganese content over 95% in the resulting purified water.

In an embodiment, the method reduces the concentration of the manganese from 0.5ppm to 0.1ppm with flow rate of approximately 1 litre per minute.

In an embodiment, the Oxidation-Adsorption media comprises filter bed of MnO2 and Green sand in a single filter. The media helps in reducing the final concentration of Iron in product water to be less than 0.3 ppm.

Iron removal efficiency is directly related to MnO2 concentration (surface area), it’s oxidation state and pH of the water. The adsorption of the Iron+2 by MnO2 ore is very rapid. Both the adsorption kinetics and adsorption capacity increases with the increasing pH and MnO2 concentration. However, MnO2 has the disadvantage of increasing the turbidity of the product water and would necessitate another sediment filter as post filter but use of sediment filter increases the pressure drop and makes the system 4-stage instead of 3-stage. The present Invention provides an efficient oxidation-adsorption media based on MnO2 and Greensand.

In an embodiment, the oxidation-adsorption media comprises filter bed of MnO2, with approximately 80% purity and Green sand bed (approximately 35% surface coated by MnO2) in a single filter.

In an embodiment, the oxidation-adsorption media comprises volumetric ratio of Greensand: MnO2 in the range of 2.4:1.2 to 3:1. This specific ratio is able to meet both the Fe reduction and turbidity less than 1 NTU for over 12,000Litres with 2ppm of feed Iron in the water.

Figure 2 illustrates results of the Iron reduction study using Three-Stage Filtration System based on calcite, Sediment filter & optimized ratio of Greensand and MnO2 media while Figure 3 illustrates filtering performance using Calcite and only Greensand.

In an embodiment, Iron reduction and Turbidity studies were performed. Figures 4 and 5 shows results of the Iron reduction study and Turbidity of resulting water correspondingly with only MnO2, Only Greensand and varying ratio (3:1, 1:3 and 1:1 volumetric ratio) of Greensand to MnO2 media. Figure 4 particularly illustrates results of the Iron reduction study using Three-Stage Filtration System with only MnO2, only Greensand and 3:1, 1:3 and 1:1 volumetric ratio of Greensand to MnO2 media while Figure 5 illustrates results of the Turbidity of product water of the above Ratios under different run conditions (continuous run and stagnation).

The results and observations of the experiments performed are as following:

(a) 4:0 volumetric ratio of GS: MnO2 causes lower iron reduction rate (Figure 4)
(b) 1:3 volumetric ratio of GS: MnO2 causes high turbidity & aesthetic issue after stagnation period (Figure 5)
(c) 1:1 volumetric ratio of GS: MnO2 causes moderate turbidity (Figure 5), even though reduction of Iron is satisfactory.
Therefore, the above mentioned ratio of GS: MnO2 in column (a), (b) and (c) cannot be used for the purpose of iron filtration. It is evident from the figures 4 and 5, that for Fe concentration less than 0.3ppm in product water, system with only MnO2, 3:1, 1:3 and 2:2 ratios of Greensand: MnO2 is able to meet Fe reduction, however does not reduce turbidity to below 1 NTU. While the volumetric ratio of Greensand: MnO2 ranges from 2.4:1.2 to 3:1 (however, in this embodiment, the ratio of Greensand: MnO2 is 3:1) is able to meet both the Fe reduction and turbidity less than 1 NTU. Figure 6 illustrates Iron reduction studies using Three-Stage Filtration System with MnO2 and Greensand where the ratios of Greensand to MnO2 are maintained as 2.8:1.2, 2.6:1.4, 2.4:1.6 and 2.2:1.8 while Figure 7 illustrates results of the turbidity studies of resulting water treated/filtered with the same ratios of Greensand to MnO2 media (i.e. 2.8:1.2, 2.6:1.4, 2.4:1.6 and 2.2:1.8) under different run conditions (continuous run and stagnation).

The present method comprises customized method steps where in first step the pH value is raised by adding pH boosting media (like calcite) followed by sedimentation and treatment with the customised oxidation-adsorption media comprising optimized ratio of MnO2 ore (with approximately 80% purity) to Greensand (approximately 35% surface coated MnO2) bed for rapid adsorption which is required when desired flow rate is more than 1 litre per minute and turbidity to be less than 1 NTU for domestic application. The volumetric ratio of Greensand: MnO2 ranging from 2.4:1.2 to 3:1 shows technically advantageous results.

In another aspect of the Invention, there is provided a water filter/purification system for removal of Iron from water by carrying out the filtration/purification method as described above.

In an embodiment, the filter/purification system for removal of heavy metals comprising Iron and manganese from water comprises essential filter media, as illustrated in Figure 1, as described below:
? pH Booster: This filter media, being the first media, causes the Oxidation of metals like Fe2+ to Fe3+, Hydrolysis of Fe3+ to iron hydroxides and precipitation of the hydroxide particles. Similar oxidation occurs for Manganese also.
? Sediment Filter: The water out of the 1st stage passes through the stage where precipitate of hydroxide particles is removed.
? Oxidation-adsorption Media: This stage of filtration having specially formulated oxidation-adsorption media combination to oxidized and adsorb the trace amount of iron present in water after the second stage of filtration and fine tune the water quality for getting maximum iron removal that is below 0.3ppm
The heavy metals comprises Iron and manganese.

In an embodiment, the Oxidation-Adsorption media comprises mixture of Greensand and MnO2 present in a specific ratio, which helps in reducing the final concentration of Iron in product water to be less than 0.3 ppm.
In an embodiment, the oxidation-adsorption media comprises optimized ratio of MnO2 ore (with approximately 80% purity) to Greensand (approximately 35% surface coated MnO2) bed.
In an embodiment, the oxidation-adsorption media comprises customized ratio of Greensand: MnO2 ranging from 2.4:1.2 to 3:1. This specific ratio is able to meet both the Fe reduction and turbidity less than 1 NTU
In an embodiment, the filter system can be used as Point of Use, which does not depend on electricity for its operations.
In another embodiment, the filter system is easy to use, has reasonable size that can be fitted in a household as point of use system.
In another embodiment, the filter system is cost effective.
In another embodiment, the filter system is portable, easy to install, standalone and electricity free system.

Advantages of the invention:
1. The filtration method of the present invention is able to achieve reduction of over 95% of Iron and manganese in final product water from 2 ppm in feed water. The filter successfully completes 12,000 Liter of product water with minimum 86% and maximum 98% of total metals like iron and manganese rejection.
2. The unique combination of oxidation-adsorption media in the filtration method and filter system for removal of iron and manganese, is able to achieve the required results in lesser media volume, which is appropriate for POU application
3. The filter system is portable, easy to install and without use of electricity.
4. The filter system can be used as standalone Iron remover or in conjugation with other technology like, RO, UV, etc.
The filtration method and system comprises appropriate pre-treatment step to eliminate the problem of fouling membranes which greatly reduce the efficiency of the RO/NF/UF membrane.
,CLAIMS:We Claim

1. A water purification method by removing heavy metal contamination from a liquid sample, comprises following steps:
a) treating said liquid sample at pH ranging from 7.2 to 8.5 where said treatment causes oxidation followed by hydrolysis for the precipitation of said heavy metal in the hydroxide form in the first pH boosting media;
b) passing the water resulting from step (a) through the first filter to a sediment filter for removing the precipitate of hydroxide form of said heavy metal;
c) treating the liquid sample resulting from the step (b) through an oxidation-adsorption filter media, where said media comprises filter bed of MnO2 and green sand present in a ratio ranging from 2.4:1.2 to 3:1, to obtain the purified water by the removal of said heavy metal contamination.
2. The method as claimed in claim 1, wherein said heavy metals comprises Iron, manganese.
3. The method as claimed in claim 1, wherein said method reduces the concentration of iron from 2 ppm to permissible drinkable limit of 0.3ppm with flow rate of approximately 1 litre per minute.
4. The method as claimed in claim 1, wherein said method reduces the concentration of the manganese from 0.5ppm to 0.1ppm with flow rate of approximately 1 litre per minute.
5. The method as claimed in claim 1, wherein said method reduces said heavy metal/s over 95% in the resulting purified water.
6. An oxidation-adsorption filter media for removing heavy metal contamination by oxidizing and adsorbing the heavy metal present in a liquid sample comprising filter bed of MnO2 and Green sand present in a ratio ranging from 2.4 :1.2 to 3:1.
7. The filter media as claimed in claim 6, comprises MnO2 with approximately 80% purity.
8. The filter media as claimed in claim 6, wherein said greensand comprises approximately its 35% surface coated with MnO2.
9. A water purifier for removing heavy metal contamination from a liquid sample, comprising:
a) atleast a pH booster media for precipitating said heavy metal in hydroxide form, where said media maintains the pH ranging from 7.2 to 8.5;
b) atleast a sediment media for removing the precipitated heavy metal resulting from the pH booster media;
c) atleast an oxidation-adsorption filter media, where said media comprises filter bed of MnO2 and green sand is present in a ratio ranging from 2.4:1.2 to 3:1, to obtain the purified water by the removal of said heavy metal contamination.
10. The water purifier as claimed in claimed in claim 9, is a point of use purifier.
11. The water purifier as claimed in claimed in claim 9, wherein said heavy metals comprises Iron, manganese.

Dated this the 14th day of August, 2018

(Suvarna Pandey)
(IN/PA-1592)
Of RNA, IP Attorneys
Agent of the Applicant