indion two bed portable deioniser

7/25/2019 INDION Two Bed Portable Deioniser

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Automatic Valveless Gravity Filter

Introduction

As the name suggests Automatic ValvelessGravity Filter (AVGF) operates automatically, onthe loss of head principle. This is generallyaccepted as being the most accurate controlbesides the constant analysis of the filtered water

turbidity, which is seldom practical on acontinuous basis. The head loss at which AVGFinitiates backwashing is determined by the heightof the inverted U-turn at the top of the backwashpipe. The level of water in this pipe isproportional to the head loss across the filterbed.

Product Description

AVGF consists of a tank divided into threefunctional compartments, a backwash storage

space, a filter bed compartment and a collectionchamber under a false bottom. The backwashstorage space is designed to hold the adequateamount of backwash water. The filter bedcompartment normally contains standard finefilter sand supported on a collection system ofdisc type plastic strainers, which provide uniformcollection of filtered water and uniformdistribution of backwash water without the use ofgravel. Standard filter sand or dual media (sandand anthracite) is generally used as the filtermedia. The AVGF can be built in cylindricalconstruction of steel or rectangular of concrete.The standard models are available in steel.

Working Principle

Filtration

Unfiltered water from the constant head box

(which is used to provide a free fall at all timesfor water entering the filter and to prevent apressure line from feeding directly into the filter)passes down the inlet pipe and enters the filterthrough an inlet wier box. Any air trapped in theunfiltered water is released through the smallvent pipe. The unfiltered water flows downward

through the filter media and the strainersinto the collection chamber. As the unfilteredwater passes through the bed of filter media, thedirt suspended impurities are trapped in the bedThe clean water from the collection chamberflows upward through the effluent duct, andwhen the backwash storage compartment hasbeen filled, it flows through the effluent pipe toservice.

As the filter bed collects dirt during the filter run,the head loss increases gradually, and the water

level slowly rises in the inlet pipe and in thebackwash pipe. Just before the water passes oveinto the downward section of the latter one, aself-actuated primer system evacuates air fromthe pipe. This pulls water rapidly over so that alarge volume of water flows down the backwashpipe and initiates the siphon action thatbackwashes the filter.

Backwashing

Once the siphon has been established betweenthe filter and the sump, the pressure immediatelyabove the filter bed is lower than the pressure inthe backwash storage compartment. This causeswater from the backwash compartment to flowdown the through the effluent duct, into thecollection chamber and upwards through thestrainers, expanding the bed and cleaning it. Thebackwash water with the dirt it has removed from


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Ion Exchange LLC46722, Fremont Blvd., Fremont, CA 94538, USA.

Phone: 408 649 5639 Fax: 408 649 5658 Email: [email protected]: www.ionexchangeglobal.com

the filter bed then passes up the backwash pipe,over the U-Bend and out through the sump to

waste. The backwash rate actually starts at a veryhigh rate (around 2.62 2.68 ft/min) andgradually slows down to around 0.82 ft/min atthe end. The performance of the various installedunits has indicated that diminishing backwashrate satisfactorily cleans the filter bed. The highinitial flow rate provides greater initial turbulenceto wash the sand. The lower flow at the end ofwash permits the bed to settle evenly andsmoothly.

The backwash action continues until the level ofthe water in the backwash storage compartmentdrops below the end of the siphon breaker.When it does, air is admitted to the top of thebackwash pipe and backwashing stops.

Rinsing

The inlet water automatically resumes itsdownward gravity flow through the filter bed assoon as the siphon is broken. The first water tobe filtered rinses the bed and then flows up intothe backwash storage compartment where it isstored for the next backwash. When thiscompartment is filled to the level of effluent pipeconnection, it goes no higher, and all waterfiltered after this flows directly to service.

When more than one filter is used, the flow isdivided equally among all the filters by means ofa flow splitting box. In addition, an interlockbetween filters is provided to prevent more thanone unit backwashing at any time.

Features

Automatic backwash, hence reliable No need of manpower - as the filter

operates automatically

No need of expensive valves,instrumentation, and backwash pumps

and hence cost competitive. No moving parts, hence less

maintenance

Uniform high quality treated water

No need of expensive power, hence lowoperating cost

Compact and modular design, hence lowexpansion and installation cost

Even though AVGF is automatic, thebackwash can be initiated manually,however, external water source at

20 30 psi has to be provided Space saving

Applications

Ideal for side stream filtration

In side stream filtration the suspended solids willbe very high in the beginning of operation, butwith time (several days typically) it will dropsignificantly (usually below 20 ppm). The AVGFis widely used to reduce turbidity of cooling towe

waters. This improves cooling tower efficiencyand reduces maintenance and cleaning costs.

Treatment for portable water

Internationally AVGF is approved and used bymajority of Municipal corporations for treatmentof potable water.

Polishing filter for domestic sewage aswell as industrial effluent

AVGF (Municipal type) can be incorporated as apolishing filter after secondary clarifier of thesewage/effluent treatment plant where usuallyload of less than 40ppm can be anticipated.


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Continuous Sand Filter

Product Description

The continous sand filter is a continuous upflowdeep bed granular media filter. The backwash isalso continuous. The filter media is moving indownflow direction and also continuouslycleaned by recycling the sand internally.

Working Principle

The feed is introduced into the lower part of thefilter bed through riser tubes which dischargeunder a distribution hood. Filtration takes placeupwards through the sand bed which is movingdownwards. Most of the suspended solids in thefeed will be separated near the feed level, whichmeans that the dirtiest sand will be found in thelower part of the filter. The sand bed is kept in aslow downward motion by an airlift pump taking

out dirty sand from close to the bottom of thefilter tank. In the air-lift pump the sand issubjected to a thorough mechanical agitation bythe action of air bubbles and the dirt isseparated from the grains of sand. The filter bedis continuously cleaned while the filter is inoperation. The dirtiest sand is continuously takenout of the filter bed, washed and returned to theclean part of the sand bed. This means that thefilter does not have to be taken out of operation

for backwashing. The dirt is finally rinsed awayfrom the sand in the sand washer, which isplaced concentrically around the upper part ofthe air-lift pump. The clean sand is returned tothe top of the filter bed. Reject water iscontinuously taken out from the sand washer.The filtrate leaves the filter as an overflow.

Features

Continuous backwash operation

Handles suspended solids load upto 150ppm

Operates at atmospheric pressure

Simple modular construction with minimummoving parts

Applications

Raw water filtration for potable use

Raw water filtration for industrial processwater

Cooling tower side stream filtration andmake up

Recycling of white water in pulp and paperindustry

Tertiary treatment of sewage, treatment ofindustrial waste water

Filtration of water to remove mill scale


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Fig-2: Vertical Pressure Sand Filter

Fig-1: Vertical Pressure Sand Filter

Pressure Sand Filter

Product Description

A typical pressure sand filter consists of apressure vessel - this could be either vertical orhorizontal-fitted with a set of frontal pipe workand valves, graded sand supported by layers ofgraded under bed consisting of pebbles and

silex, a top distributor to distribute the incomingwater uniformly throughout the cross section ofthe filter, and an under drain system to collectfiltered water. Fig 1 shows the arrangement of avertical pressure sand filter.

Working Principle

In pressure sand filter raw water flows downwards through the filter bed and as thesuspended matter- which has usually beentreated by addition of a coagulant like alum- is

retained on the sand surface ands between thesand grains immediately below the surface.There is steady rise in the loss of head as thefiltration process continues and the flow reducesonce the pressure drop across the filter isexcessive.

The filter is now taken out of service andcleaning of the filter is effected by flow reversal.To assist in cleaning the bed, the backwash

operation is often preceded by air agitationthrough the under drain system. The process ofair scouring agitates the sand with a scrubbingaction, which loosens the intercepted particles.The filter is now ready to be put back intoservice.


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Fig-1 - Elevation and internal arrangement of themultigrade filter

Multi Grade Filter

Product Description

Multigrade filter is a depth filter that makes useof coarse and fine media mixed together in afixed proportion. This arrangement produces afilter bed with adequate pore dimensions forretaining both large and small suspended

particles. This filter performs at a substantiallyhigher specific flow rate than conventional filters.Specific flow rates of 0.82 1.64 ft/min havebeen successfully obtained for treating waterscontaining 25 50 ppm suspended solidsrespectively to produce filtrate with less than5 ppm.

Features

Higher specific velocity Raw water can be used for backwashing

the filter

Applications

The INDION Multigrade filter is an ideal choicefor all applications where a conventional sandfilter is used. It is extensively used in side streamfiltration of cooling water and in potable watertreatment. It is ideal for filtration of clarifiedwater. In addition it finds application in seawater filtration and in filtration of chemicalsolutions. For these types of filtration rubber linedor epoxy painted filters are used.


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Metal Removal Sulfex Process

Introduction

Hydroxide precipitation, which is conventional processfor removal of heavy metals from wastewater has twodrawbacks:

Some metal hydroxides tend to re-dissolve uponincreasing the pH value above a certain critical

value. This is called "amphoterism". In case of amixture of heavy metals, an operating pH ideallysuited for efficient removal of one metal isunfavorable for the good removal of the other.

In the presence of chelating agents such as EDTA,metal hydroxide precipitation is incomplete.

With ever increasing stringent limits for effluentdisposal, hydroxide precipitation cannot meet therequired permissible limits.

The development of Sulfex process eliminates both theabove deficiencies and has been in commercial usefor several years. This precipitation technique involves

an exchange of sulphide ion between ferrous sulphideand the heavy metal ion present in the effluent aspollutant.

Sulfex Process Principle

In order to precipitate any of the heavy metals assulphides, the sulphide source added to the solutionof the metal must be more soluble than the metalsulphide to be precipitated. As the added sulphidedissolves, the dissociated sulphide ion then reactsreadily with the heavy metal that has lower sulphidesolubility. When equilibrium is reached, the metal oflower solubility will be precipitated and the one ofhigher solubility will remain dissolved.

In the Sulfex process FeS is used as the sulphidesource. Starting with a soluble sulphide, such asSodium Hydrogen Sulphide, (NaHS), this is reactedwith an equivalent or excess amount of ferrous ion(Fe ++) so that there can be no excess sulphide

relative to the ferrous ion. Therefore, the only ionicsulphide that will be present is due to the solubility ofFeS.

Features

Since FeS is rather insoluble, only 3 x 10-2 ppb o

free sulphide is present in a natural aqueoussolution. This concentration is too low to producean odour of Hydrogen Sulphide, but it is highenough to react with the Heavy metals that areless soluble when combined with sulphide.

Fe 2+ + S 2- + M 2+ + S04 2- + Ca (OH)2 =MS + Fe(OH)2 + SO4 2- + Ca 2+ (Wheresymbols have usual meaning)

The pH of the water is maintained in the range of8.5 to 9.0 causing the iron to precipitate asferrous hydroxide. Iron is relatively insolubleunder these conditions, normally less than 0.5mg/lit, such concentration of iron are considered

nontoxic and acceptable in an ecological system.

The addition of lime (or caustic) to elevate the pHand precipitate the excess iron also improves theremoval of heavy metal sulphides because theytoo are less soluble at the higher pH values.

The main advantage of the Sulfex process is itsability to remove hexavalent chromium in onestep as opposed to the typical two-step processused with hydroxide precipitation. Possiblereaction is as follows:Cr04 2- + 4H20 + FeS = S + Fe(OH) 3 +Cr(OH)3 + 20H- Here Chromium is removed as

hydroxide precipitate.

Applications

Metal processing industry

Metal refining

Automobile industry


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Two Bed Portable Deioniser

Introduction

D.M. plants consists of cation unit and anion unitplaced one after other in seris . The cation unit ischarged with strong acid cation resin & anionunit is charged with strong base unit.D. M . plants remove all the anions & cationsfrom the water. Conductivity of the treated wateris in the range of 0 to 40 -cm. The cation resinis regenerated with Hydrochloric acid & anionresin with Caustic solution. Then the cation unit isrinsed with feed water and anion unit withdecationised water till the acceptable waterquality is achieved.

Product Description

INDION Two bed portable deionisers producedemineralised water at flow rates upto2.65 gpm. They are easy to install andeconomical to operate. Their design is tooutcome of many years of experience inmanufacturing deionisers to meet the specificrequirements of many industries. The units aremade of corrosion resistant materials ofconstruction - pressure vessel of FRP, plastic

tubes, moulded rubber components, plasticcoated stands, FRP panels etc.

When the capacity of the ion exchanger isexhausted, it is regenerated: the cationexchanger with dilute hydrochloric acid and theanion exchanger with caustic soda solution. Theunits are pre-assembled and tested before

despatch and easy to install.

Advantages

Ready to use

Portable, can be moved to points of use

Complete with regeneration equipment anda multi-valve control block

Continuous monitoring of treated waterquality

Applications

Battery top up

Laboratory and research institutions

Pharmaceuticals

Chemicals

Electroplating and mirror silvering

indion two bed portable deioniser

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