Title of Invention	"WATER DEFERRIZATION UNIT FOR FERRUGINOUS WATER AND A PROCESS THEREOF"
Abstract	The present invention relates to a water deferrization unit comprising of a filtration tank, an aeration system with cover, a doser stand, a doser, and one or more openings for water flow; wherein the said filtration tank, having one or more chambers which are inter connected to form sedimentation chamber, up-flow filtration chamber, down flow filtration chamber and a filter water chamber; said up-filtration chamber, down flow filtration chamber have backwash outlet valves; and said sedimentation chamber is having a pair of removable perforated trays containing chemically treated gravel and sludge outlet valve. The present invention also provides a process of deferrization raw water having higher amount if iron present in the water to water having less that 0.3 ppm of iron content.

Title of Invention

"WATER DEFERRIZATION UNIT FOR FERRUGINOUS WATER AND A PROCESS THEREOF"

Abstract

The present invention relates to a water deferrization unit comprising of a filtration tank, an aeration system with cover, a doser stand, a doser, and one or more openings for water flow; wherein the said filtration tank, having one or more chambers which are inter connected to form sedimentation chamber, up-flow filtration chamber, down flow filtration chamber and a filter water chamber; said up-filtration chamber, down flow filtration chamber have backwash outlet valves; and said sedimentation chamber is having a pair of removable perforated trays containing chemically treated gravel and sludge outlet valve. The present invention also provides a process of deferrization raw water having higher amount if iron present in the water to water having less that 0.3 ppm of iron content.

Full Text	"WATER DEFERRIZATION UNIT FOR FERRUGINOUS WATER AND A PROCESS THEREOF-FIELD OF INVENTION This invention relates to a water deferrization unit capable of providing filtered water containing about or less than 0.3 ppm iron. The present invention particularly relates to a water deferrization unit which treats water containing iron up to 40 ppm. The present invention also relates to a process of treating high iron content water using novel deferrization unit. BACKGROUND AND PRIOR ART Different designs of iron removal plants have been developed by various agencies to get rid of excess iron from water. These iron removal plants are of DANIDA type, WHO type, BASTER type and the 'HAND PUMP ATTACHABLE IRON REMOVAL PLANT' adopted by Bureau of Indian Standards, IS 12918: 1990. One of the drawbacks of DANIDA type iron removal plant is the absence of the sedimentation chamber, which lowers efficiency of the filter media. Another drawback of this plant is that it is suitable for ferruginous water containing 7-8 ppm iron only. The WHO type iron removal plant does not have any sedimentation chamber and gravity filtration is used which leads to early chocking of filter bed necessitating frequent cleaning. Another drawback of WHO type plant is that backwash is not possible in hand pump schemes. Yet another drawback of this plant is that it is suitable for ferruginous water containing 7-8 ppm iron only. The drawback of BASTER type iron removal plant is that complete cleaning of filter water chamber is complicated due to its direct inaccessibility and the maintenance requirement is high. Another drawback of this plant is that it is suitable for ferruginous water containing 7-8 ppm of iron only. The drawback of the Bureau of Indian Standards adopted iron removal plant is that cleaning of filter bed is carried out with unfiltered water, through filter water chamber, contaminating the filter water chamber. Another disadvantage of this iron removal plant is that complete cleaning of filter water chamber is complicated due to its direct inaccessibility. Yet another disadvantage is that the overflow pipe given in filter chamber leads to settled water overflow. There is a need for an efficient water deferrization unit to deliver water having 0.3 ppm iron and the installation, operation and maintenance of which is easier, can be installed in remote areas, can be fabricated and assembled even in rural conditions and can deliver drinking water of desired quality in respect of iron content even in rural areas from ferruginous water containing as high as 40 ppm iron. OBJECTS OF THE PRESENT INVENTION The primary object of the present invention is to provide a water deferrization unit which provides drinking water containing less than 0.3 ppm iron. Another object of the present invention is to provide a water deferrization unit which provides drinking water containing less than 0.3 ppm iron from ferruginous water containing upto 40 ppm iron. Further object of the present invention is to provide a water deferrization unit which is easier to install, operate and maintain. Another object of the present invention is to provide a water deferrization unit where cleaning / backwashing of filter beds are carried out with filter water. Further object of the present invention is to provide a water deferrization unit which can be fabricated even in rural conditions. Still further object of the present invention is to provide a water deferrization unit which is easily transportable. SUMMARY OF THE INVENTION The present invention provides an improved water deferrization unit suitable for removing excess iron from ferruginous water. The water deferrization unit made of M.S. is cylindrical in shape and coated with paint used in drinking water tank, having an efficient aeration system with cover, a doser for addition of lime suspension, iron oxide coated gravel as catalyst, sand as filter media in double filtration device and sludge/ backwash outlet valves for cleaning. The water deferrization unit is designed for 300 liters / hour output and can cater to the need of small size population. The iron content of the treated water through this unit is brought down to below 0.3 ppm from feed water containing as high as 40 ppm. The Construction of double filtration chamber (up flow and down flow) in present invention differs from prior art construction, as those are single filtration plant, either up flow or down flow. The inventive features of the present invention are the double filtration device along with aeration system, pH adjustment with lime suspension, use of catalyst (iron oxide coated gravel) and sedimentation chamber. The four outlet valves enable easier maintenance. DELAILED DESCRIPTION OF THE INVENTION The present invention provides a water deferrization unit comprising of a filtration tank, an aeration system with cover, a doser stand, a doser, and one or more openings for water flow; wherein the said filtration tank, having one or more chambers which are inter connected to form sedimentation chamber, up-flow filtration chamber, down flow filtration chamber and a filter water chamber; said up-filtration chamber, down flow filtration chamber have backwash outlet valves; and said sedimentation chamber is having a pair of removable perforated trays containing chemically treated gravel and sludge outlet valve. The gravity flow chamber is also called as down-flow filtration chamber. The base of the said filtration tank is elevated along the central partition of up-flow filtration chamber and down flow filtration chamber The aeration system of the water deferrization unit consists of a dome shaped top cover, two convex perforated discs and a perforated concave disc, facing the water flow, fitted co-axially with the help of adjustable knobs. The gravel is treated with oxidizing agents such as ferric oxide. The up-flow and the down-flow filtration chambers of the water deferrization unit have sand supported over gravel as filter media. The sedimentation chamber has a sludge outlet valve which enables the removal of the sediments of the flocculated iron. The up flow and down flow filtration chambers in combination with the sedimentation chamber provides filtered water containing less than 0.3 ppm of iron. The backwash outlet valves of the water deferrization unit enable the cleaning of the filter chambers with filtered water. The doser which placed on a doser stand is fitted onto the upper end of the sedimentation chamber of the filtration tank. The doser contains basic solution. The water deferrization unit of the present invention consists of an overflow outlet, a raw water inlet and a filter water outlet. Another embodiment of the invention provides a process of deferrization water, wherein said method comprising of: a. passing inlet water through an aeration system for exchanging of gases from raw water and to increase the dissolved oxygen content; of raw water; b. adding basic solution suspension from a doser to the aerated water of step (a), c. passing the base treated water of step (b) through a pair of removable perforated trays in the sedimentation chamber containing chemically treated gravel which oxidizes ferrous ions to ferric ions, and the sedimentation chamber having a sludge outlet valve, where flocculation of precipitated iron and the sedimentation of the flocculated iron can be achieved and the sludge can be removed through sludge outlet valve; d. passing the water from the sedimentation chamber of step (c) through an up-flow chamber for removal of iron particles still present in the water; e. passing the water from the up flow chamber of step (d) through a down flow filtration chamber for removal of iron particles still present in the water; and f. collecting the water from the down flow chamber of step(e) in a filter chamber, wherein the filtered water can be tapped through filtered water outlet. One of the embodiment of the invention provides a process of deferrization water of raw water which contains iron more than or upto 40 ppm. The aeration system of the water deferrizaiton unit increases the dissolved oxygen content of raw water up to level ranging between 3.0 - 7.0 ppm. The doser contains basic solution which increases the pH of water above 7.0. The up flow and the down flow filtration device in combination with the sedimentation device results in filtered water containing less than 0.3 ppm of iron. It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive BRIEF DESCRIPTION OF DRAWINGS Figure 1 shows the water deferrization unit. Figure 2 represents the filtration tank. Figure 3 is the plan filtration tank Figure 4 represents the cross section A-A of the filtration tank Figure 5 represents the cross section B-B of the filtration tank. Figure 6 is the aeration system of the embodiment. Figure 7 shows the plan aeration system. Figure 8 shows the cover for aeration system.. Figure 9 shows the doser stand. Figure 10 shows the doser bottle. DETAILED DESCRIPTION OF THE DRAWINGS Filtration tank (2) is cylindrical in shape having four chambers viz. sedimentation (11), up flow filtration (12), gravity flow filtration (13) and filter water (14) chamber. These chambers are housed in cylindrical main body, separated by partitions having openings for flow of water. The base of the filtration tank is elevated along the central partition (15) of the two filtration chambers. At the upper end of sedimentation chamber a removable perforated tray (16) is placed over another removal perforated tray (17). These two trays contain chemically treated gravels (18). The sedimentation chamber is also fitted with an over flow pipe (19). The sedimentation chamber is connected to the up flow filtration chamber with horizontal opening (20) at the bottom of the partition separating them. A sludge out let valve (21) is fitted at the lower most end of the sedimentation chamber. The up flow filtration chamber houses a perforated tray (22) on which rests, the support gravel (23) and sand (24). Through openings (25) in the central partition, the up flow filtration chamber is connected with the gravity flow filtration chamber. One backwash outlet valve (26) is fitted outside the up flow filtration chamber. The gravity flow filtration chamber also houses a removable perforated tray (27) on which rests the support gravel and sand. One back wash outlet valve (28) is also fitted outside gravity flow filtration chamber. The gravity flow filtration chamber is connected with the filter water chamber through a horizontal opening (29) at the bottom of partition separating them. The filter water chamber is fitted with a filter water outlet (30) and a backwash outlet valve (31). The filtration tank is fitted with handles (32) and rests on legs (33). The aeration system (6) consists of an upper convex disc (34), a lower convex disc (35) and a perforated concave disc (36). The raw water inlet pipe (37) is horizontal up to the center of the base (38) of aeration system and then through a 90° turn stands vertically. The three discs, as mentioned above are fitted coaxially over vertical portion of the raw water inlet pipe with adjustable knob (39). The aeration base serves as a cover of filtration tank and has holes (40) at one end for flow of aerated water to the sedimentation chamber. The aeration system is removable and fitted with handles (41). Top portion (42) of cover (8) for aeration system is dome shaped and is fully covered and sides (43) consist of MS mesh and fitted with handles (44). This cover will prevent the aeration system as well as the filtration tank from any leaf, litter or rain water etc. into the system. The doser stand (9) is fitted at the upper end of the sedimentation chamber, with fitting device (45) and has a rest base (46) for doser. The doser bottle (10) is fitted with a tap (47) and a tube (48). INSTALLATION The filtration tank is placed on horizontally levelled hard stand on ground level near water source. The doser stand is fitted outside the sedimentation chamber and the doser container containing lime suspensions is placed on doser stand. The iron oxide coated gravels are then spread on to the two trays of sedimentation chamber and support gravel and sand are spread on to the tray of up flow and gravity flow filtration chamber. The support gravel and filter sand are then cleaned till clear water accumulates in the filter water chamber. The aeration system is placed on the top of filtration tank in such a way so that the holes on the base of aeration system. placed above the sedimentation chamber. The cover of aeration system is placed over the aeration system. Water inlet of the water deferrization unit is connected to the water source, and all the valves and water outlet are closed. OPERATION The water inlet of water deferrization unit is connected to the raw / untreated water source. The untreated water passes through the water inlet pipe and then finds its way out at the other end of the pipe and then spread over on the top convex disc and from the periphery of this disc enters into the perforated concave disc. Through perforations of 1 concave disc the water enters and spread over on the top of lower convex disc and then from periphery of this disc enters on the base of aeration system. During operation of the unit lime suspensions are added drop wise through the tube of doser to raise the pH of v water above 7.0. The water exchanges gases while passing over this aeration system and the aerated water then flows to the filter tank through perforations on base of aeration system. In the filter tank water first flows over chemically treated gravel placed on removable perforated trays at the upper end of the sedimentation chamber and then flows to the sedimentation chamber while passing through the above system water exchanges I gases, increases pH and ferrous iron gets oxidized to ferric ion. In the sedimentation chamber, iron is coagulated and then it precipitates and settles at the bottom of the sedimentation chamber. Precipitated iron, 90 % (85 - 95%) are retained in this chamber and drained out periodically through sludge outlet. The water then finds it way to the up flow filtration chamber and passes through filtration media which retains the unsettled iron particles. From up flow filtration chamber water flows to the gravity filtration chamber through openings above the filtration media and passes through the gravity filtration device. This filter removes the fine particles of the unsettled iron and clear water enters to the filter water chamber. Clear water is tapped through the filtered water outlet. Performance evaluation of the water deferrization unit is given in Table -1. Also the comparison Table-2 shows the difference between various designs and the present invention Table -1: Performance evaluation of water deferrization unit (Table Removed) Table -2: Comparison of various iron removal plants (Table Removed) MAINTENANCE OF WATER DEFERRIZATION UNIT Maintenance of the water deferrization unit is easierthan before. Periodic back washings are required in order to clean the filter media, as the voids are filled with iron particles. The sedimentation chamber is required to be cleaned weekly. The unit needs back washings at monthly intervals (depending on iron content of feed water) and the filter media needs replacement when there is no improvement in the filter efficiency even after back washings. Back washings and cleaning operations in sequence are done as under: (i) The aeration system (6) and its cover (8) are removed from the top of the water deferrization unit. (ii) Treated water delivery tap (30) and sludge/ back wash out let valves (21, 26, 28 and 31) are closed and level of filtered water allowed to rise to its maximum, (iii) Filter media, sand (24) of the gravity flow filtration chamber (13), is shaken / raked by hand. Back wash outlet valve (28) is opened and washed water is allowed to come out through this valve. Raking / shaking is to be continued till clear water accumulates over the filter bed. (iv) Filter water chamber (14) is cleaned by opening the back wash outlet valve (31) and dirty water is drained off. (v) Backwash outlet valves (28) and (31) are closed and level of filter water is allowed to rise to its maximum, (vi) Filter media of the up flow filtration chamber (12) is shaken / raked. Back wash outlet valve (26) is opened and washed water is allowed to come out through this valve. Shaking/ raking is to be continued till clear water accumulate over the filter bed. (vii) Sedimentation chamber (11) is cleaned by opening the sludge outlet valve (21) to drain out the dirty water, (viii) Operations (ii) to (vii) are to be repeated if required, (ix) Aeration system and its cover are replaced in original position and all valves are to be closed before operation of iron removal. Advantages of the present invention The advantages of the water deferrization unit are-  adequate aeration,  major portion of iron settles in sedimentation chamber,  double filtration ensures better iron removal,  efficient backwashing system,  filter bed cracking prevented and clogging delayed and  easy installation operation and maintenance. I / WE CLAIM 1. A water deferrization unit comprising of a filtration tank, an aeration system with cover, a doser stand, a doser, and one or more openings for water flow; wherein the said filtration tank, having one or more chambers which are inter connected to form sedimentation chamber, up-flow filtration chamber, down flow filtration chamber and a filter water chamber; said up-filtration chamber, down flow filtration chamber have backwash outlet valves; and said sedimentation chamber is having a pair of removable perforated trays containing chemically treated gravel and sludge outlet valve. 2. The water deferrization unit as in claim 1, wherein the base of the said filtration tank is elevated along the central partition of up-flow filtration chamber and down flow filtration chamber. 3. The water deferrization unit as claimed in claim 1, wherein the aeration system consists of a dome shaped top cover, two convex perforated discs and a perforated concave disc, facing the water flow, fitted co-axially with the help of adjustable knobs. 4. The water deferrization unit as in claim 1, wherein the said up-flow and the down-flow filtration chambers have sand supported over gravel as filter media. 5. The water deferrization unit as in claim 1, wherein the said sedimentation chamber has a sludge outlet valve. 6. The water deferrization unit as claimed in claim 1, wherein the up flow and down flow filtration chambers in combination with the sedimentation chamber provides filtered water containing less than 0.3 ppm of iron. 7. The water deferrization unit as claimed in claim 1, wherein the said backwash outlet valves enable the cleaning of the filter chambers with filtered water. 8. The water deferrization unit as claimed in claim 1, wherein the said doser, placed on a doser stand, which is fitted onto the upper end of the sedimentation chamber of the filtration tank, contains basic solution. 9. The water deferrization unit as claimed in claim 1, consisting of an overflow outlet, a raw water inlet and a filter water outlet. 10. A process of deferrization water, said method comprising of: a. passing inlet water through an aeration system for exchanging of gases from raw water and to increase the dissolved oxygen content; of raw water; b. adding basic solution suspension from a doser to the aerated water of step (a), c. passing the base treated water of step (b) through a pair of removable perforated trays in the sedimentation chamber containing chemically treated gravel which oxidizes ferrous ions to ferric ions, and the sedimentation chamber having a sludge outlet valve, where flocculation of precipitated iron and the sedimentation of the flocculated iron can be achieved and the sludge can be removed through sludge outlet valve; d. passing the water from the sedimentation chamber of step (c) through an up-flow chamber for removal of iron particles still present in the water; e. passing the water from the up flow chamber of step (d) through a down flow filtration chamber for removal of iron particles still present in the water; and f. collecting the water from the down flow chamber of step(e) in a filter chamber, wherein the filtered water can be tapped through filtered water outlet. 11. A process of deferrization water as claimed claim 10, wherein the raw water contains iron more than 40 ppm 12. A process of deferrization water as claimed claim 10, wherein the raw water contains iron upto 40 ppm 13. A process of deferrization water as claimed claim 10, wherein the aeration system increases the dissolved oxygen content of raw water up to level ranging between 3.0 - 7.0 ppm. 14. A process of deferrization water as claimed claim 10, wherein basic solution suspension from a doser increases the pH of water above 7.0. 15. A process of deferrization water as claimed claim 10 provides water containing less than 0.3 ppm of iron.

Full Text

"WATER DEFERRIZATION UNIT FOR FERRUGINOUS WATER AND A
PROCESS THEREOF-FIELD OF INVENTION
This invention relates to a water deferrization unit capable of providing filtered water containing about or less than 0.3 ppm iron. The present invention particularly relates to a water deferrization unit which treats water containing iron up to 40 ppm. The present invention also relates to a process of treating high iron content water using novel deferrization unit. BACKGROUND AND PRIOR ART
Different designs of iron removal plants have been developed by various agencies to get rid of excess iron from water. These iron removal plants are of DANIDA type, WHO type, BASTER type and the 'HAND PUMP ATTACHABLE IRON REMOVAL PLANT' adopted by Bureau of Indian Standards, IS 12918: 1990.
One of the drawbacks of DANIDA type iron removal plant is the absence of the sedimentation chamber, which lowers efficiency of the filter media. Another drawback of this plant is that it is suitable for ferruginous water containing 7-8 ppm iron only.
The WHO type iron removal plant does not have any sedimentation chamber and gravity filtration is used which leads to early chocking of filter bed necessitating frequent cleaning. Another drawback of WHO type plant is that backwash is not possible in hand pump schemes. Yet another drawback of this plant is that it is suitable for ferruginous water containing 7-8 ppm iron only.
The drawback of BASTER type iron removal plant is that complete cleaning of filter water chamber is complicated due to its direct inaccessibility and the maintenance requirement is high. Another drawback of this plant is that it is suitable for ferruginous water containing 7-8 ppm of iron only.
The drawback of the Bureau of Indian Standards adopted iron removal plant is that cleaning of filter bed is carried out with unfiltered water, through filter water chamber, contaminating the filter water chamber. Another disadvantage of this iron removal plant is that complete cleaning of filter water
chamber is complicated due to its direct inaccessibility. Yet another disadvantage is that the overflow pipe given in filter chamber leads to settled water overflow.
There is a need for an efficient water deferrization unit to deliver water having 0.3 ppm iron and the installation, operation and maintenance of which is easier, can be installed in remote areas, can be fabricated and assembled even in rural conditions and can deliver drinking water of desired quality in respect of iron content even in rural areas from ferruginous water containing as high as 40 ppm iron.
OBJECTS OF THE PRESENT INVENTION
The primary object of the present invention is to provide a water deferrization unit which provides drinking water containing less than 0.3 ppm iron.
Another object of the present invention is to provide a water deferrization unit which provides drinking water containing less than 0.3 ppm iron from ferruginous water containing upto 40 ppm iron.
Further object of the present invention is to provide a water deferrization unit which is easier to install, operate and maintain.
Another object of the present invention is to provide a water deferrization unit where cleaning / backwashing of filter beds are carried out with filter water.
Further object of the present invention is to provide a water deferrization unit which can be fabricated even in rural conditions.
Still further object of the present invention is to provide a water deferrization unit which is easily transportable.
SUMMARY OF THE INVENTION
The present invention provides an improved water deferrization unit suitable for removing excess iron from ferruginous water. The water deferrization unit made of M.S. is cylindrical in shape and coated with paint used in drinking water tank, having an efficient aeration system with cover, a doser for addition of lime suspension, iron oxide coated gravel as catalyst, sand as filter media in double filtration device and sludge/ backwash outlet
valves for cleaning. The water deferrization unit is designed for 300 liters / hour output and can cater to the need of small size population. The iron content of the treated water through this unit is brought down to below 0.3 ppm from feed water containing as high as 40 ppm. The Construction of double filtration chamber (up flow and down flow) in present invention differs from prior art construction, as those are single filtration plant, either up flow or down flow. The inventive features of the present invention are the double filtration device along with aeration system, pH adjustment with lime suspension, use of catalyst (iron oxide coated gravel) and sedimentation chamber. The four outlet valves enable easier maintenance.
DELAILED DESCRIPTION OF THE INVENTION
The present invention provides a water deferrization unit comprising of a filtration tank, an aeration system with cover, a doser stand, a doser, and one or more openings for water flow;
wherein the said filtration tank, having one or more chambers which are inter connected to form sedimentation chamber, up-flow filtration chamber, down flow filtration chamber and a filter water chamber;
said up-filtration chamber, down flow filtration chamber have backwash outlet valves; and
said sedimentation chamber is having a pair of removable perforated trays containing chemically treated gravel and sludge outlet valve.
The gravity flow chamber is also called as down-flow filtration chamber.
The base of the said filtration tank is elevated along the central partition of up-flow filtration chamber and down flow filtration chamber
The aeration system of the water deferrization unit consists of a dome shaped top cover, two convex perforated discs and a perforated concave disc, facing the water flow, fitted co-axially with the help of adjustable knobs.
The gravel is treated with oxidizing agents such as ferric oxide.
The up-flow and the down-flow filtration chambers of the water deferrization unit have sand supported over gravel as filter media.
The sedimentation chamber has a sludge outlet valve which enables the removal of the sediments of the flocculated iron.
The up flow and down flow filtration chambers in combination with the sedimentation chamber provides filtered water containing less than 0.3 ppm of iron.
The backwash outlet valves of the water deferrization unit enable the cleaning of the filter chambers with filtered water.
The doser which placed on a doser stand is fitted onto the upper end of the sedimentation chamber of the filtration tank. The doser contains basic solution.
The water deferrization unit of the present invention consists of an overflow outlet, a raw water inlet and a filter water outlet.
Another embodiment of the invention provides a process of deferrization water, wherein said method comprising of:
a. passing inlet water through an aeration system for exchanging of
gases from raw water and to increase the dissolved oxygen content;
of raw water;
b. adding basic solution suspension from a doser to the aerated water
of step (a),
c. passing the base treated water of step (b) through a pair of
removable perforated trays in the sedimentation chamber containing
chemically treated gravel which oxidizes ferrous ions to ferric ions,
and the sedimentation chamber having a sludge outlet valve, where
flocculation of precipitated iron and the sedimentation of the
flocculated iron can be achieved and the sludge can be removed
through sludge outlet valve;
d. passing the water from the sedimentation chamber of step (c)
through an up-flow chamber for removal of iron particles still present
in the water;
e. passing the water from the up flow chamber of step (d) through a
down flow filtration chamber for removal of iron particles still present
in the water; and
f. collecting the water from the down flow chamber of step(e) in a filter chamber, wherein the filtered water can be tapped through filtered water outlet.
One of the embodiment of the invention provides a process of deferrization water of raw water which contains iron more than or upto 40 ppm.
The aeration system of the water deferrizaiton unit increases the dissolved oxygen content of raw water up to level ranging between 3.0 - 7.0 ppm.
The doser contains basic solution which increases the pH of water above 7.0.
The up flow and the down flow filtration device in combination with the sedimentation device results in filtered water containing less than 0.3 ppm of iron.
It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive
BRIEF DESCRIPTION OF DRAWINGS
Figure 1 shows the water deferrization unit.
Figure 2 represents the filtration tank.
Figure 3 is the plan filtration tank
Figure 4 represents the cross section A-A of the filtration tank
Figure 5 represents the cross section B-B of the filtration tank.
Figure 6 is the aeration system of the embodiment.
Figure 7 shows the plan aeration system.
Figure 8 shows the cover for aeration system..
Figure 9 shows the doser stand.
Figure 10 shows the doser bottle.
DETAILED DESCRIPTION OF THE DRAWINGS
Filtration tank (2) is cylindrical in shape having four chambers viz. sedimentation (11), up flow filtration (12), gravity flow filtration (13) and filter water (14) chamber. These chambers are housed in cylindrical main body, separated by partitions having openings for flow of water. The base of the filtration tank is elevated along the central partition (15) of the two filtration chambers. At the upper end of sedimentation chamber a removable perforated tray (16) is placed over another removal perforated tray (17). These two trays contain chemically treated gravels (18). The sedimentation chamber is also fitted with an over flow pipe (19). The sedimentation chamber is connected to the up flow filtration chamber with horizontal opening (20) at the bottom of the partition separating them. A sludge out let valve (21) is fitted at the lower most end of the sedimentation chamber.
The up flow filtration chamber houses a perforated tray (22) on which rests, the support gravel (23) and sand (24). Through openings (25) in the central partition, the up flow filtration chamber is connected with the gravity flow filtration chamber. One backwash outlet valve (26) is fitted outside the up flow filtration chamber.
The gravity flow filtration chamber also houses a removable perforated tray (27) on which rests the support gravel and sand. One back wash outlet valve (28) is also fitted outside gravity flow filtration chamber. The gravity flow filtration chamber is connected with the filter water chamber through a horizontal opening (29) at the bottom of partition separating them. The filter water chamber is fitted with a filter water outlet (30) and a backwash outlet valve (31). The filtration tank is fitted with handles (32) and rests on legs (33). The aeration system (6) consists of an upper convex disc (34), a lower convex disc (35) and a perforated concave disc (36). The raw water inlet pipe (37) is horizontal up to the center of the base (38) of aeration system and then through a 90° turn stands vertically. The three discs, as mentioned above are fitted coaxially over vertical portion of the raw water inlet pipe with adjustable knob (39). The aeration base serves as a cover of filtration tank and has holes (40) at one end for flow of aerated water to the sedimentation chamber. The aeration system is removable and fitted with handles (41).
Top portion (42) of cover (8) for aeration system is dome shaped and is fully covered and sides (43) consist of MS mesh and fitted with handles (44). This cover will prevent the aeration system as well as the filtration tank from any leaf, litter or rain water etc. into the system.
The doser stand (9) is fitted at the upper end of the sedimentation chamber, with fitting device (45) and has a rest base (46) for doser.
The doser bottle (10) is fitted with a tap (47) and a tube (48).
INSTALLATION
The filtration tank is placed on horizontally levelled hard stand on ground level near water source. The doser stand is fitted outside the sedimentation chamber and the doser container containing lime suspensions is placed on doser stand. The iron oxide coated gravels are then spread on to the two trays of sedimentation chamber and support gravel and sand are spread on to the tray of up flow and gravity flow filtration chamber. The support gravel and filter sand are then cleaned till clear water accumulates in the filter water chamber. The aeration system is placed on the top of filtration tank in such a way so that the holes on the base of aeration system. placed above the sedimentation chamber. The cover of aeration system is placed over the aeration system. Water inlet of the water deferrization unit is connected to the water source, and all the valves and water outlet are closed.
OPERATION
The water inlet of water deferrization unit is connected to the raw / untreated water source. The untreated water passes through the water inlet pipe and then finds its way out at the other end of the pipe and then spread over on the top convex disc and from the periphery of this disc enters into the perforated concave disc. Through perforations of 1 concave disc the water enters and spread over on the top of lower convex disc and then from periphery of this disc enters on the base of aeration system. During operation of the unit lime suspensions are added drop wise through the tube of doser to raise the pH of v water above 7.0. The water exchanges gases while passing over this aeration system and the aerated water then flows to the filter tank
through perforations on base of aeration system. In the filter tank water first flows over chemically treated gravel placed on removable perforated trays at the upper end of the sedimentation chamber and then flows to the sedimentation chamber while passing through the above system water exchanges I gases, increases pH and ferrous iron gets oxidized to ferric ion. In the sedimentation chamber, iron is coagulated and then it precipitates and settles at the bottom of the sedimentation chamber. Precipitated iron, 90 % (85 - 95%) are retained in this chamber and drained out periodically through sludge outlet. The water then finds it way to the up flow filtration chamber and passes through filtration media which retains the unsettled iron particles. From up flow filtration chamber water flows to the gravity filtration chamber through openings above the filtration media and passes through the gravity filtration device. This filter removes the fine particles of the unsettled iron and clear water enters to the filter water chamber. Clear water is tapped through the filtered water outlet.
Performance evaluation of the water deferrization unit is given in Table -1.
Also the comparison Table-2 shows the difference between various designs and the present invention
Table -1: Performance evaluation of water deferrization unit

(Table Removed)
Table -2: Comparison of various iron removal plants

(Table Removed)
MAINTENANCE OF WATER DEFERRIZATION UNIT
Maintenance of the water deferrization unit is easierthan before. Periodic back washings are required in order to clean the filter media, as the voids are filled with iron particles. The sedimentation chamber is required to be cleaned weekly. The unit needs back washings at monthly intervals (depending on iron content of feed water) and the filter media needs replacement when there is no improvement in the filter efficiency even after back washings.
Back washings and cleaning operations in sequence are done as under: (i) The aeration system (6) and its cover (8) are removed from the top of
the water deferrization unit.
(ii) Treated water delivery tap (30) and sludge/ back wash out let valves
(21, 26, 28 and 31) are closed and level of filtered water allowed to rise
to its maximum, (iii) Filter media, sand (24) of the gravity flow filtration chamber (13), is
shaken / raked by hand. Back wash outlet valve (28) is opened and
washed water is allowed to come out through this valve. Raking /
shaking is to be continued till clear water accumulates over the filter
bed. (iv) Filter water chamber (14) is cleaned by opening the back wash outlet
valve (31) and dirty water is drained off. (v) Backwash outlet valves (28) and (31) are closed and level of filter water
is allowed to rise to its maximum, (vi) Filter media of the up flow filtration chamber (12) is shaken / raked.
Back wash outlet valve (26) is opened and washed water is allowed to
come out through this valve. Shaking/ raking is to be continued till clear
water accumulate over the filter bed. (vii) Sedimentation chamber (11) is cleaned by opening the sludge outlet
valve (21) to drain out the dirty water, (viii) Operations (ii) to (vii) are to be repeated if required, (ix) Aeration system and its cover are replaced in original position and all
valves are to be closed before operation of iron removal.
Advantages of the present invention
The advantages of the water deferrization unit are-
 adequate aeration,
 major portion of iron settles in sedimentation chamber,
 double filtration ensures better iron removal,
 efficient backwashing system,
 filter bed cracking prevented and clogging delayed and
 easy installation operation and maintenance.

I / WE CLAIM
1. A water deferrization unit comprising of a filtration tank, an aeration system
with cover, a doser stand, a doser, and one or more openings for water
flow;
wherein the said filtration tank, having one or more chambers which are
inter connected to form sedimentation chamber, up-flow filtration
chamber, down flow filtration chamber and a filter water chamber;
said up-filtration chamber, down flow filtration chamber have backwash
outlet valves; and
said sedimentation chamber is having a pair of removable perforated
trays containing chemically treated gravel and sludge outlet valve.
2. The water deferrization unit as in claim 1, wherein the base of the said filtration tank is elevated along the central partition of up-flow filtration chamber and down flow filtration chamber.
3. The water deferrization unit as claimed in claim 1, wherein the aeration system consists of a dome shaped top cover, two convex perforated discs and a perforated concave disc, facing the water flow, fitted co-axially with the help of adjustable knobs.
4. The water deferrization unit as in claim 1, wherein the said up-flow and the down-flow filtration chambers have sand supported over gravel as filter media.
5. The water deferrization unit as in claim 1, wherein the said sedimentation chamber has a sludge outlet valve.
6. The water deferrization unit as claimed in claim 1, wherein the up flow and down flow filtration chambers in combination with the sedimentation chamber provides filtered water containing less than 0.3 ppm of iron.
7. The water deferrization unit as claimed in claim 1, wherein the said backwash outlet valves enable the cleaning of the filter chambers with filtered water.
8. The water deferrization unit as claimed in claim 1, wherein the said doser, placed on a doser stand, which is fitted onto the upper end of the sedimentation chamber of the filtration tank, contains basic solution.
9. The water deferrization unit as claimed in claim 1, consisting of an overflow outlet, a raw water inlet and a filter water outlet.
10. A process of deferrization water, said method comprising of:
a. passing inlet water through an aeration system for exchanging of
gases from raw water and to increase the dissolved oxygen content;
of raw water;
b. adding basic solution suspension from a doser to the aerated water
of step (a),
c. passing the base treated water of step (b) through a pair of
removable perforated trays in the sedimentation chamber containing
chemically treated gravel which oxidizes ferrous ions to ferric ions,
and the sedimentation chamber having a sludge outlet valve, where
flocculation of precipitated iron and the sedimentation of the
flocculated iron can be achieved and the sludge can be removed
through sludge outlet valve;
d. passing the water from the sedimentation chamber of step (c)
through an up-flow chamber for removal of iron particles still present
in the water;
e. passing the water from the up flow chamber of step (d) through a
down flow filtration chamber for removal of iron particles still present
in the water; and
f. collecting the water from the down flow chamber of step(e) in a filter
chamber, wherein the filtered water can be tapped through filtered
water outlet.
11. A process of deferrization water as claimed claim 10, wherein the raw water contains iron more than 40 ppm
12. A process of deferrization water as claimed claim 10, wherein the raw water contains iron upto 40 ppm
13. A process of deferrization water as claimed claim 10, wherein the aeration system increases the dissolved oxygen content of raw water up to level ranging between 3.0 - 7.0 ppm.
14. A process of deferrization water as claimed claim 10, wherein basic solution suspension from a doser increases the pH of water above 7.0.
15. A process of deferrization water as claimed claim 10 provides water containing less than 0.3 ppm of iron.

Documents:

http://ipindiaonline.gov.in/patentsearch/GrantedSearch/viewdoc.aspx?id=i4Tdxi6U2zVedCJccPGgRQ==&loc=+mN2fYxnTC4l0fUd8W4CAA==

« Previous Patent

Next Patent »

Patent Number

278389

Indian Patent Application Number

2728/DEL/2005

PG Journal Number

53/2016

Publication Date

23-Dec-2016

Grant Date

21-Dec-2016

Date of Filing

10-Oct-2005

Name of Patentee

DIRECTOR GENERAL, DEFENCE RESEARCH & DEVELOPMENT ORGANISATION

Applicant Address

MINISTRY OF DEFENCE, GOVT OF INDIA, WEST BLOCK-VIII, WING 1 SEC-1, RK PURAM, NEW DELHI-110066

Inventors:

#	Inventor's Name	Inventor's Address
1	GOSWAMI, CHANDRA, DIPAK	DEFENCE RESEARCH LABORATORY POST BAG NO.2, TEZPUR-784001
2	KALITA, HIRAN	DEFENCE RESEARCH LABORATORY POST BAG NO.2, TEZPUR-784001
3	DAS, HIMANGSHU, BIKASH	DEFENCE RESEARCH LABORATORY POST BAG NO.2, TEZPUR-784001
4	DUBE, NATH, SHASHI	DEFENCE RESEARCH LABORATORY POST BAG NO.2, TEZPUR-784001
5	BORAH, KUSUM	DEFENCE RESEARCH LABORATORY POST BAG NO.2, TEZPUR-784001
6	SAIKIA, BIJOY, LAKSHYA	DEFENCE RESEARCH LABORATORY POST BAG NO.2, TEZPUR-784001
7	DAS, CHANDRA, SUBASH	DEFENCE RESEARCH LABORATORY POST BAG NO.2, TEZPUR-784001

PCT International Classification Number

C02F 1/64

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA